135 files changed, 17 insertions, 26995 deletions
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..d7b82bc
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,4 @@
+*.txt text eol=lf
+*.htm text eol=lf
+*.html text eol=lf
+*.md text eol=lf
diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..6312041
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,11 @@
+This eBook, including all associated images, markup, improvements,
+metadata, and any other content or labor, has been confirmed to be
+in the PUBLIC DOMAIN IN THE UNITED STATES.
+
+Procedures for determining public domain status are described in
+the "Copyright How-To" at https://www.gutenberg.org.
+
+No investigation has been made concerning possible copyrights in
+jurisdictions other than the United States. Anyone seeking to utilize
+this eBook outside of the United States should confirm copyright
+status under the laws that apply to them.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..d0869d0
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+Project Gutenberg (https://www.gutenberg.org) public repository for
+eBook #50696 (https://www.gutenberg.org/ebooks/50696)
diff --git a/old/50696-0.txt b/old/50696-0.txt
deleted file mode 100644
index 2bb3241..0000000
--- a/old/50696-0.txt
+++ /dev/null
@@ -1,11473 +0,0 @@
-Project Gutenberg's Railway Construction, by William Hemmingway Mills
-
-This eBook is for the use of anyone anywhere in the United States and most
-other parts of the world at no cost and with almost no restrictions
-whatsoever.  You may copy it, give it away or re-use it under the terms of
-the Project Gutenberg License included with this eBook or online at
-www.gutenberg.org.  If you are not located in the United States, you'll have
-to check the laws of the country where you are located before using this ebook.
-
-
-
-Title: Railway Construction
-
-Author: William Hemmingway Mills
-
-Release Date: December 15, 2015 [EBook #50696]
-
-Language: English
-
-Character set encoding: UTF-8
-
-*** START OF THIS PROJECT GUTENBERG EBOOK RAILWAY CONSTRUCTION ***
-
-
-
-
-Produced by Chris Curnow, Carol Brown, and the Online
-Distributed Proofreading Team at http://www.pgdp.net (This
-file was produced from images generously made available
-by The Internet Archive)
-
-
-
-
-
-
-
-
-
-  _LONGMANS’ CIVIL ENGINEERING SERIES_
-
-  RAILWAY CONSTRUCTION
-
-
-
-
-  LONGMANS’
-
-  CIVIL ENGINEERING SERIES
-
-
-NOTES ON DOCKS AND DOCK CONSTRUCTION.
-
-  By C. COLSON, C.B., M.Inst.C.E., Deputy Civil Engineer-in-Chief,
-  Loan Works, Admiralty. With 365 Illustrations. Medium 8vo, 21_s._
-  _net._
-
-CALCULATIONS IN HYDRAULIC ENGINEERING:
-
-  A Practical Text-Book for the Use of Students, Draughtsmen, and
-  Engineers.
-
-    By T. CLAXTON FIDLER, M.I.C.E., Professor of Engineering,
-    University College, Dundee.
-
-    Part I. Fluid Pressure and the Calculation of its Effects in
-    Engineering Structures. With numerous Illustrations and
-    Examples. Medium 8vo, 6_s._ 6_d._ _net._
-
-    Part II. Calculations in Hydro-Kinetics. With numerous
-    Illustrations and Examples. Medium 8vo, 7_s._ 6_d._ _net._
-
-NOTES ON CONSTRUCTION IN MILD STEEL:
-
-  Arranged for the Use of Junior Draughtsmen in the Architectural
-  and Engineering Professions. With 425 Illustrations from Working
-  Drawings, Diagrams and Tables. By HENRY FIDLER, M.I.C.E. Medium
-  8vo, 16_s._ _net._
-
-RAILWAY CONSTRUCTION.
-
-  By W. H. MILLS, M.I.C.E., Engineer-in-Chief, Great Northern
-  Railway of Ireland. With 516 Illustrations. Medium 8vo, 18_s._
-  _net._
-
-PRINCIPLES AND PRACTICE OF HARBOUR CONSTRUCTION.
-
-  By WILLIAM SHIELD, F.R.S.E., M.Inst.C.E., and Executive Engineer,
-  National Harbour of Refuge, Peterhead, N.B. With 97 Illustrations.
-  Medium 8vo, 15_s._ _net._
-
-CIVIL ENGINEERING AS APPLIED IN CONSTRUCTION.
-
-  By LEVESON FRANCIS VERNON-HARCOURT, M.A., M.Inst.C.E. With 368
-  Illustrations. Medium 8vo, 14_s._ _net._
-
-SANITARY ENGINEERING WITH RESPECT TO WATER-SUPPLY AND SEWAGE DISPOSAL.
-
-  By LEVESON FRANCIS VERNON-HARCOURT, M.A., M.Inst.C.E. With 287
-  Illustrations. Medium 8vo, 14_s._ _net._
-
-TIDAL RIVERS: their (1) Hydraulics, (2) Improvement, (3) Navigation.
-
-  By W. H. WHEELER, M.Inst.C.E. With 75 Illustrations. Medium 8vo,
-  16_s._ _net._
-
-
- LONGMANS, GREEN, AND CO.
- LONDON, NEW YORK, BOMBAY, AND CALCUTTA
-
-  [Illustration:
-  _Frontispiece._]  KINSUA VIADUCT, ERIE RAILWAY, U.S.A.  [_See p. 97._]
-
-
-
-
-  _LONGMANS’ CIVIL ENGINEERING SERIES_
-
-  RAILWAY CONSTRUCTION
-
-
-  BY
-
-  WILLIAM HEMINGWAY MILLS, M.INST.C.E.
-
-  PAST PRESIDENT OF THE INSTITUTION OF CIVIL ENGINEERS OF IRELAND, AND
-  ENGINEER-IN-CHIEF OF THE GREAT NORTHERN
-  RAILWAY OF IRELAND
-
-  [Illustration]
-
-  _WITH ILLUSTRATIONS_
-
-  FOURTH IMPRESSION
-
-  LONGMANS, GREEN, AND CO.
-  39 PATERNOSTER ROW, LONDON
-  NEW YORK, BOMBAY, AND CALCUTTA
-  1910
-
-  _All rights reserved_
-
-
-
-
-PREFACE
-
-
-The construction and maintenance of a railway calls for the
-application of so many branches of engineering that several volumes
-would be required to do ample justice to a subject so comprehensive
-and ever-extending. To avoid attempting so wide a range, the object of
-the following pages has been to describe briefly some of the
-recognized leading features which regulate railway construction, and
-to assist the explanation with sketches of works selected from actual
-practice.
-
-Where the number of existing good examples is legion, it is somewhat
-difficult to make a choice for illustration, and the course adopted
-has been to select such samples of structures as appear best to
-elucidate in a simple manner the different types of work under
-consideration.
-
-In the drawings and diagrams many important minor details are
-necessarily omitted, partly to avoid complexity, but principally to
-leave more prominent the leading features of the particular piece of
-work referred to in the description. Some of the sketches of the large
-span bridges and large span roofs are only shown in outline; but, as
-their principal dimensions are given, a general idea can be obtained
-of their actual proportions.
-
-No allusion is made to the requisite strengths of the various
-structures described, nor to the necessary dimensions of the materials
-used in their construction, as this would necessitate the introduction
-of a vast amount of mathematical formulæ which does not come under the
-province of the object in view, and which the engineer has already at
-command from his training and works of reference.
-
-Neither is any mention made as to the probable cost of the different
-works of construction, as these must always vary to a very large
-extent, according to the locality, facility of supply, and current
-prices of materials.
-
-Every railway scheme which is the outcome of public enterprise has its
-commercial aspect and influence. The large sums to be invested in its
-construction are expected to yield permanent and increasing returns,
-and this desirable end can only be attained where there is thorough
-efficiency in works and equipment, and a full compliance with those
-national regulations which control matters connected with public
-safety. The correct dealing with the technical requirements and
-structural features of the undertaking must always precede all other
-considerations, as the constituted authorities will exact a proper
-fulfilment of all the statutory obligations, regardless of the
-prospective remuneration to the promoters. A stroke of the pen may
-change a train-service, or alter the rates and tariffs, but a
-modification in the works of construction arising out of errors or
-oversight, would entail a heavy expenditure and tedious delay. The
-essential point of every railway undertaking must be its suitability
-and completeness in every respect for the duty for which it is
-intended.
-
-Notes of what has been done are always valuable for consideration and
-comparison, and that the following brief description and sketches may
-be found useful for reference, is the earnest wish of the writer.
-
-  W. H. MILLS,
-    M.INST.C.E.
-
-
-
-
-  CONTENTS
-
-
-  CHAPTER I.
-
-                                                                 PAGE
-
-  Location of a line of railway--Government regulations--Questions
-  for consideration in connection with gauge, gradients, and
-  curves                                                            1
-
-
-  CHAPTER II.
-
-  Works of construction: Earthworks, Culverts, Bridges,
-  Foundations, Screw piles, Cylinders, Caissons, Retaining
-  walls, and Tunnels                                               60
-
-
-  CHAPTER III.
-
-  Permanent way--Rails--Sleepers--Fastenings--and Permanent-way
-  laying                                                          182
-
-
-  CHAPTER IV.
-
-  Stations: Station Buildings, Roofs, Lines, and Sidings          248
-
-
-  CHAPTER V.
-
-  Sorting-sidings--Turn-tables--Traversers--Water-Tanks and
-  Water-Columns                                                   285
-
-
-  CHAPTER VI.
-
-  Comparative Weights of some Types of Modern Locomotives         304
-
-
-  CHAPTER VII.
-
-  Signals--Interlocking--Block Telegraph and Electric Train
-  Staff Instruments                                               313
-
-
-  CHAPTER VIII.
-
-  Railways of different ranks--Progressive improvements--Growing
-  tendency for increased speeds, with corresponding increase in
-  weight of permanent way and rolling-stock--Electricity as a
-  motive-power                                                    348
-
-  INDEX                                                           361
-
-
-
-
-  CHAPTER I.                                                                1
-
-  Location of a line of railway--Government regulations--Questions
-    for consideration in connection with gauge, gradients, and
-    curves.
-
-
-Location.--The locating of a line of railway, or the determination
-of its exact route, is influenced by many circumstances. In a rich
-country, with thickly populated districts and large industrial
-enterprises, there are towns to be served, manufacturing centres to be
-accommodated, and harbours to be brought into connection; while, at
-the same time, there may be important estates which must be avoided
-and private properties which must not be entered. Each point will
-present its own individual claim for consideration when selecting the
-route which promises the greatest amount of public convenience and
-commercial success.
-
-In new countries--in our colonies, and especially out in the far west
-of Canada and the United States--railways have to be laid out in
-almost uninhabited districts, where there is but little population or
-commerce to serve, and where the principal object is to obtain the
-best and most direct route through the vast territories, leaving
-colonists and settlers to choose afterwards the most convenient sites
-for towns and villages. Untrammelled by the network of public and
-private roads and properties which are met with at home, it might
-appear that the locating of such a line would be comparatively light;
-but even in such countries, which at first sight seem to present
-unlimited freedom for selecting a route, much can be done, and should
-be done, by taking a course through those plains and districts which
-possess the best natural resources for future agricultural,
-manufacturing, or mineral development.
-
-In addition to the motives of convenience and policy, the route of
-every line of railway must be influenced by the natural features of
-the country--the mountains, valleys, and rivers. These physical
-obstacles are in some cases on such an enormous scale as to compel          2
-long detours in the formation of a more suitable opening; and in
-others, although the difficulties are not insurmountable, they may
-involve works of great magnitude and expense.
-
-In a comparatively rich country, with a prospect of large and
-remunerative traffic, a succession of heavy works, bridges, and
-tunnels may be admissible and expedient; but in new countries economy
-of outlay has to be considered, and costly works avoided as much as
-possible.
-
-Every one of the heavy works on a line, whether lofty bridges, long
-viaducts, or costly tunnels, not only enormously increase the original
-expenditure of the undertaking, but also entail large annual outlay in
-the necessary constant supervision and maintenance.
-
-Each particular scheme will have to be discussed on its own individual
-merits. The heavy, high-speed passenger traffic line will suggest
-light gradients and easy curves, while on secondary lines and in
-thinly populated districts it may be prudent, for the sake of economy,
-to introduce sharper curves and heavier gradients. Even in the latter
-case, and especially in new countries, it is well to keep in view the
-future possibilities of the undertaking. The steeper the gradients,
-the greater the cost and time in working the traffic, and if there is
-every probability of early and large development, the prospective
-increase may warrant an additional outlay in the original
-construction.
-
-Large, open plains and wide valleys of important rivers generally
-afford ample latitude for the selection of a suitable route, and, by
-taking advantage of the gradations of altitude, a favourable course
-may be adopted without incurring excessive gradients. When traversing
-moderately hilly districts, some low ridge or opening may be found,
-which may form a pass from the one side to the other, and the line may
-be laid out for a long distance to lead gradually up to the highest
-point. But when a route has to be laid out over some of those lofty
-mountain ranges which are met with abroad, the locating of a suitable
-line, or of any line, becomes particularly intricate and difficult. A
-comparatively low ridge may be found possessing features in favour of
-the project, but the question will be how to reach that point. The
-nearer the summit of these high mountains, the more precipitous the
-sides; no one slope can be found sufficiently long and uniform to           3
-permit a practical direct ascent, and the only way out of the
-difficulty is to make a series of detours along the various spurs of
-the mountains to gain length to overcome the height. Each detour has
-to be the subject of most careful study. Forming part of a long series
-of ascending gradients, it has to follow the winding of the
-mountain-side, must be laid out to be always gaining in height, and
-will comprise important works, many of them of considerable extent,
-necessary for protection against the floods and atmospherical changes
-of the locality.
-
-In these higher altitudes nature is met with on the grandest and most
-rugged scale. Deep gorges, wide ravines, and almost perpendicular
-rocks form the pathway along which the line must be carried, and the
-skill of the engineer is taxed to the utmost to select a course which
-shall comprise a minimum of the works of magnitude. Mile after mile of
-line must be laid out in almost inaccessible places, loose or broken
-rocks must be avoided, a firm foundation must be obtained at all
-points skirting high ledges, and ample provision must be made for
-those mountain torrents which rise so suddenly, and are liable to
-sweep away all before them.
-
-Many grand examples of these detour lines are in existence in
-different parts of the world, and the traveller passing over them can
-realize the difficulties that had to be encountered, and the masterly
-manner in which they have been overcome.
-
-Before proceeding to carry out the works of any line of railway, it is
-necessary to prepare a complete plan and section of the line, showing
-the route to be followed and the position of the various curves,
-gradients, and principal works. Within certain limits, the course of
-the line may have to be slightly modified as the work proceeds, in
-consequence of ground turning out unfavourable, river-crossings
-treacherous, or of sites involving so many contingent alterations that
-it is found better to avoid them altogether. The route should,
-however, be so carefully studied out before completing the final plan
-and section, as to leave only minor deviations of line and level to be
-dealt with in the actual carrying out of the work.
-
-The promoters of lines in the United Kingdom obtain valuable
-assistance from the ordnance maps, which give full and reliable
-information regarding the position of all roads, rivers, and
-boundaries of counties, parishes, and townlands. In many parts abroad       4
-local maps are scarce, and not always accurate, and engineers have to
-depend principally on their own surveys, and rely upon the resident
-local authorities for any particulars as to divisions of territory. On
-some of our great colonial plains, and out in the far west of America,
-a line may be laid out for miles without a single landmark to localize
-it on a plan; but careful setting out, and the relative levels of the
-ground and gradients, as shown on the section, will always indicate
-the correct position of any portion of the work.
-
-Both at home and abroad complete plans and sections of any proposed
-railway must be deposited with the proper Government authorities, and
-must be approved and sanctioned by them before permission can be
-obtained to proceed with the works.
-
-The regulations regarding the scale and general arrangement of these
-plans and sections vary in different countries, and are subject to
-modification from time to time.
-
-Each country has its own special enactments relative to the method of
-dealing with roads, rivers, streams, and public and private property
-proposed to be interfered with in the construction of any line, and a
-knowledge of these is absolutely necessary for the promoters of any
-new scheme, inasmuch as some of the requirements may, in certain
-instances, influence the precise route to be selected.
-
-The English Government has passed several Acts of Parliament setting
-forth the general conditions which must be complied with in the
-construction of any railway in the United Kingdom. These conditions,
-or standing orders, relate both to the acquirement of land and
-property, the size and description of works for public or private
-accommodation, and the inspection and official approval of the
-undertaking when completed. These fixed regulations are alike valuable
-to the promoters and to the public; the former are informed of the
-principal points with which the scheme must conform, and the latter
-know the limit of their legal demands.
-
-No line of railway, or extension of any railway, will obtain
-Parliamentary sanction unless it can be satisfactorily proved in the
-outset, that its construction would be of public advantage. This point
-is of paramount importance, and due weight must be given to it when
-preparing to refute the evidence of opponents to the scheme.
-
-[Illustration: Fig. 1.]
-
-When conceding the right to make any railway, Parliament grants with        6
-it the power to purchase lands or property compulsorily, or by
-agreement, to change and divert roads and streams in the manner shown
-on the deposited plans, and to construct all necessary bridges and
-works in accordance with the standing orders, or such modifications of
-them as may be approved by the Board of Trade.
-
-The standing orders, or Government regulations, are very
-comprehensive, and include much detailed information on all questions
-likely to arise. The following brief summary of some of the principal
-orders relating to deposited plans, and works of construction, will be
-found useful for reference.
-
-
-Extract from Government Standing Orders and Regulations.--All
-plans and sections relative to proposed new railways must be lodged
-with the constituted Government Authorities on or before November 30.
-
-Every deposited plan must be drawn to a scale of not less than four
-inches to a mile, and must describe the centre line, or situation of
-the work (no alternative line being allowed), and must show all lands,
-gardens, or buildings within the limits of deviation, each one being
-numbered with a reference number, and where powers to make lateral
-deviations are applied for, the limits of such deviation must be
-marked on the plan.
-
-Unless the whole of such plan be drawn to a scale of not less than 400
-feet to an inch, an enlarged plan must be drawn to that scale of every
-building and garden within the limits of deviation.
-
-The Railway Clauses Act limits the extent of deviation to 100 yards on
-each side of the centre line in the country, and 10 yards on each side
-of the centre line in towns or villages.
-
-The distances must be marked on the plan in miles and furlongs from
-one of the termini.
-
-The radius of every curve not exceeding one mile must be marked on the
-plan in furlongs and chains.
-
-In tunnels the centre line must be dotted, but no work must be shown
-as tunnelling, in the making of which it is necessary to cut through,
-or remove the surface soil. If it is intended to divert or alter any
-public road, navigable river, canal, or railway, the course and extent
-of such diversion, etc., shall be marked on the plan.
-
-[Illustration: Fig. 2.]
-
-When a railway is to form a junction with an existing railway, the          8
-course of such existing railway must be shown on the plan for a
-distance of 800 yards on each side of the proposed junction. In the
-case of Bills for constructing subways, the plans and sections must
-indicate the height and width of such subway, and the nature of the
-approaches by which it is proposed to afford access to such subway.
-
-The Book of Reference must contain the names of all owners, lessees,
-and occupiers of all lands and houses of every parish within the
-limits of deviation.
-
-The numbers on the Book of Reference must correspond with the numbers
-on the plan, and opposite to each number must be entered a brief
-description of the property, whether field, garden, house, road,
-railway, or river. It is intended that the plan and Book of Reference
-together, shall afford ample information to enable all parties
-interested to ascertain to what extent their property will be affected
-by the proposed undertaking.
-
-The section must be drawn to the same horizontal scale as the plan,
-and to a vertical scale of not less than 100 feet to an inch, and must
-show the level of the ground, the level of the proposed work, the
-height of every embankment, the depth of every cutting, and a
-horizontal datum line which shall be referred to some fixed point,
-near one of the termini.
-
-In every section of a railway, the line of railway marked thereon must
-correspond with the upper surface of the rails.
-
-Distances on the datum line must be marked in miles and furlongs to
-correspond with those on the plan; a vertical measure from the datum
-line to the line of the railway must be marked in feet and decimals at
-the commencement and termination of the railway, and at each change of
-gradient, and the rate of inclination between such vertical measures
-must also be marked.
-
-Wherever the line of railway crosses any public carriage road,
-navigable river, canal, or railway, the height of the railway over, or
-depth beneath the surface thereof, and the height and span of every
-arch by which the railway will be carried over the same, must be
-marked in figures.
-
-[Illustration: Fig. 3.]
-
-In the case of a public road level crossing, it must be described on
-the section, and it must also be stated if such level will be
-unaltered. If any alteration be intended in the level of any canal,
-public road, or railway which will be crossed by the intended line of
-railway, the same must be stated on the section and cross-sections to
-a horizontal scale of not less than 330 feet to an inch, and a vertical    10
-scale of not less than 40 feet to an inch must be added, which must
-show the present surface of such road, canal, etc., and the intended
-surface thereof when altered, and the greatest of the present and
-intended rates of inclination marked in figures, such cross-sections
-to extend 200 yards on each side of the centre line of railway.
-
-Wherever the height of any embankment, or depth of any cutting, shall
-exceed 5 feet, the extreme height over or depth beneath the surface of
-the ground must be marked in figures upon the section.
-
-All tunnels and viaducts must be shown on the section.
-
-At a junction with an existing railway, the gradient of such existing
-railway must be shown on the section on the same scale as the general
-section for a distance of 800 yards on each side of the point of
-junction.
-
-Where the level of any turnpike or public road has to be altered in
-making any railway, the gradient of any altered road need not be
-better than the mean inclination of the existing road within a
-distance of 250 yards of the point of crossing the railway; but where
-the existing roads have easy gradients, then the gradients of the
-altered roads, whether carried over, or under, or on the level with
-the railway, must not be steeper than 1 in 30 for a turnpike road, 1
-in 20 for a public carriage road, 1 in 16 for a private or occupation
-road.
-
-A good and sufficient fence, 4 feet high at least, shall be made on
-each side of every bridge, and fences 3 feet high on the approaches.
-
-The application to cross any public road on the level must be reported
-upon by one of the officers of the Board of Trade, and special
-permission for the work must be embodied in the Act.
-
-Not more than 20 houses of the labouring classes may be purchased in
-any city or parish in England, Scotland, and Wales, or more than 10
-such houses in Ireland, until approval has been obtained to a scheme
-for building such houses in lieu thereof as the authorities may deem
-necessary.
-
-Every bridge (unless specially authorized to be otherwise) must
-conform with the following regulations:--
-
-A bridge over a turnpike road must have a clear span of 35 feet on the
-square between the abutments, with a headway, or height, of 16 feet
-for a width of 12 feet, as shown on Fig. 12.
-
-[Illustration: Fig. 4.]
-
-A bridge over a public road must have a clear span of 25 feet on the       12
-square between the abutments, with a headway of 15 feet for a width of
-10 feet, as shown on Fig. 13.
-
-A bridge over a private or occupation road must have a clear span of
-12 feet on the square between the abutments, with a headway of 14 feet
-for a width of 9 feet, as shown on Fig. 14.
-
-Road bridges over the railway must have the same clear width between
-the parapets, measured on the square, as the widths prescribed for
-road bridges under the railway, or 35 feet for a turnpike road, 25
-feet for a public road, and 12 feet for private or occupation road.
-
-It is not compulsory, however, to construct the public road bridges
-over or under the railway of a greater width than the average
-available width of the existing roads within 50 yards of the point of
-crossing the railway, but in no case must a bridge have a less width
-than 20 feet. Should the narrow roads be widened at any future time,
-the railway company will be under the obligation to widen the bridges
-at their own expense to the extent of the statutory widths of 35 feet
-for a turnpike road, and 25 feet for a public road.
-
-Suitable accommodation works in the form of bridges, level crossings,
-gates, or other works, must be provided for the owners, or occupiers
-of lands, or properties intersected or affected by the construction of
-the railway; or payments may be made by agreement instead of
-accommodation works. All questions, or differences between the Railway
-Company, and the owners or occupiers of property affected, will be
-decided by the authorities duly appointed by the Government for the
-purpose.
-
-In constructing the railway, the Parliamentary plans and sections may
-be deviated from to the following extent:--
-
-The centre line may be deviated anywhere within the limits of
-deviation (100 yards on each side of the centre line in country, and
-10 yards each side in towns, or villages).
-
-Curves may be sharpened up to half a mile radius, and further, if
-authorized by the Board of Trade.
-
-A tunnel may be made instead of a cutting, and a viaduct instead of an
-embankment, if authorized by the Board of Trade.
-
-The levels may be deviated from to the extent of 5 feet in the
-country, and 2 feet in a town, or village, and various authorities
-have power to consent to further deviations.
-
-[Illustration: Fig. 5.]
-
-Gradients may be diminished to any extent, gradients flatter than 1 in
-100 may be made steeper to the extent of 10 feet in a mile, and            14
-gradients steeper than 1 in 100 may be made steeper to the extent of 3
-feet in a mile, or to such further extent as may be authorized by the
-Board of Trade.
-
-Suitable fences must be erected on each side of the line, to separate
-the land taken for the use of the railway from the adjoining lands not
-taken, and to protect such lands from trespass, or the cattle of the
-owners, or occupiers thereof from straying on to the railway.
-
-In addition to the Parliamentary plans, and sections, and Book of
-Reference, an estimate of the cost of each separate line, or branch,
-must be prepared as near to the following form as circumstances will
-permit.
-
-  ESTIMATE OF THE PROPOSED                    (RAILWAY).
-
-  Line No._______
-  ------------------------------------------+-----------------------------
-                    Miles.     F.      Chs. |   Whether single or double.
-  Length of Line:    ____     ____     ____ |   _______________________
-  -----------------------+--------------+---+------+-----------+----------
-                         | Cubic yards. | Price per | £ _s. d._ | £ _s. d._
-                         |              |   yard.   |           |
-                         +--------------+-----------+-----------+---------
-  Earthworks:--          |              |           |           |
-     Cuttings--Rock      |              |           |           |
-               Soft soil |              |           |           |
-               Roads     |              |           |           |
-                         +--------------+-----------+-----------+
-                   Total |              |           |           |
-                         +--------------+-----------+-----------+
-                                                                |
-  Embankments, including roads, ____ cubic yards                |
-  Bridges, public roads--number                                 |
-  Accommodation bridges and works                               |
-  Viaducts                                                      |
-  Culverts and drains                                           |
-  Metallings of roads and level crossings                       |
-  Gatekeepers’ houses at level crossings                        |
-  Permanent way, including fencing:--                           |
-                                                                |
-                 Miles.    F.   Chs.     |     Cost per mile.   |
-                                         |    £    _s._  _d._   |
-                  ____   ____   ____  at |   ____  ____  ____   |
-                                                                |
-  Permanent way for sidings, and cost of junctions              |
-  Stations                                                      |
-                                                                +---------
-  Contingencies ____ per cent.                                  |
-                                                                +---------
-                       A.    R.    P.                           |
-  Land and buildings  ____  ____  ____                          |
-                                                                +---------
-                                                      Total   £ |
-                                                                +=========
-  Dated this _______ day of ______________________ 18____
-
-  Witness: __________________________
-
-                                  ___________________________________
-                                                            Engineer.
-
-[Illustration: Fig. 6.]
-
-The same details for each branch, and general summary of total cost.       16
-Every Railway Bill must be read twice, both in the House of Commons
-and in the House of Lords. A committee, duly appointed for each House,
-must report upon it, and if the reports from such committees be
-favourable, the Bill will be read a third time, and passed.
-
-When it has passed both Houses, the Bill receives the Royal Assent,
-and becomes law.
-
-The minimum scale of four inches to a mile for the plans is so very
-small that it is rarely, if ever, adopted. It would necessitate
-enlarged plans of so many portions to show clearly the property or
-buildings inside the limits of deviation, that in practice it is found
-expedient to make the plans to a much larger scale.
-
-Figs. 1 and 2 show a small portion of a Parliamentary plan and section
-drawn to the minimum scale allowed, with an enlargement of a small
-part to distinguish the houses clearly.
-
-Figs. 3 and 4 show a part of the same plan and section drawn to a
-scale of 400 feet to an inch, a scale which is very frequently
-adopted, and is sufficiently large to distinguish the buildings and
-small plots, except in closely populated districts. This scale also
-gives ample room for reference numbers.
-
-The Parliamentary plans and sections must be accurate in delineation,
-levels, and description. All property within the prescribed limits of
-deviation must be clearly shown, and the numbers and description on
-the plans and book of reference must be concise and complete, to
-enable the owners to ascertain to what extent they will be affected.
-In every place where it is proposed to interfere with any public
-highway, street, footpath, river or canal, the manner of such proposed
-alteration must be shown and described on both plan and section. The
-commencement and termination of every tunnel must be correctly
-indicated, and the length given on both plan and section. An omission
-of any of the above requirements might prove very detrimental to the
-scheme, and possibly result in the Bill being thrown out of Parliament
-for non-compliance with standing orders.
-
-[Illustration: Fig. 7.]
-
-In carrying out the works the constructors have power to deviate the
-centre line either to the one side or the other, provided that such
-deviation will permit of the boundary of the works, or property to be
-acquired, to come within the limits of deviation or property               18
-referenced, and they may also vary the levels of the line to the
-extent prescribed in the standing orders.
-
-Figs. 5 and 6 are parts of a Parliamentary plan and section showing
-alteration of a public road with an overline bridge--also a diversion
-of a small river to avoid two river bridges.
-
-Figs. 7 and 8 are parts of a Parliamentary plan and section showing a
-public road diverted and carried under the railway.
-
-A stipulated time is fixed in the Bill for the purchase of the
-property and construction of the line, and if this time be exceeded
-before the completion of the works, it will be necessary to obtain
-further Parliamentary powers for an extension of time.
-
-Every new railway, or extension of railway, in the United Kingdom,
-must be inspected, and certified, by one of the inspecting officers of
-the Board of Trade, previous to Government sanction being granted for
-its opening as a passenger line.
-
-To facilitate these inspections, and as a guide both to their own
-inspecting officers and the engineers in charge of the construction,
-the Board of Trade have issued a list of the principal requirements in
-connection with all new lines.
-
-The following is a copy of the list so far as relates to works of
-construction and signals:--
-
-
-Requirements of the Board of Trade.--1. The requisite apparatus
-for providing by means of the block telegraph system an adequate
-interval of space between following trains, and, in the case of
-junctions, between converging or crossing trains. In the case of
-single lines worked by one engine under steam (or two or more coupled
-together) carrying a staff, no such apparatus will be required.
-
-2. Home-signals and distant-signals for each direction to be fixed at
-stations and junctions, with extra signals for such dock, or bay
-lines, as are used either for the arrival, or for the departure of
-trains, and starting-signals for each direction, at all passenger
-stations which are also block posts. On passenger lines all cross-over
-roads and all connections for goods, or mineral lines, and sidings to
-be protected by home and distant signals, and as a rule at all
-important running junctions a separate distant-signal to be provided
-in connection with each home-signal.
-
-[Illustration: Fig. 8.]
-
-_Signals may be dispensed with on single lines under the following
-conditions_:--
-
-(_a_) _At all stations and siding connections upon a line worked by        20
-one engine only (or two engines coupled together), carrying a staff,
-and when all points are locked by such staff._
-
-(_b_) _At any intermediate siding connection upon a line worked under
-the train staff and ticket system, or under the electric staff or tablet
-system, where the points are locked by the staff or tablet._
-
-(_c_) _At intermediate stations, which are not staff or tablet
-stations, upon a line worked under the electric staff or tablet
-system: Sidings, if any, being locked as in (b)._
-
-3. The signals at junctions to be on separate posts, or on brackets;
-and the signals at stations, when there is more than one arm on one
-side of a post, to be made to apply--the first, or upper arm, to the
-line on the left, the second arm to the line next in order from the
-left, and so on; but in cases where the main, or more important line,
-is not the one on the left, separate signal-posts to be provided, or
-the arms to be on brackets. Distant-signals to be distinguished by
-notches cut out of the ends of the arms, and to be controlled by home
-or starting signals for the same direction when on the same post. A
-distant-signal arm must not be placed above a home or starting signal
-arm on the same post for trains going in the same direction.
-
-In the case of sidings, a low short arm and a small signal light,
-distinguishable from the arms or lights for the passenger lines, may
-be employed, but in such cases disc signals are, as a rule,
-preferable.
-
-Every signal arm to be so weighted as to fly to and remain at danger
-on the breaking at any point of the connection between the arm and the
-lever working it.
-
-4. On new lines worked independently, the front signal lights to be
-green for “all right,” and red for “danger;” the back lights (visible
-only when the signals are at “danger”) to be white.
-
-_This requirement not to be obligatory in the case of new lines run
-over by trains of other companies using a different system of
-lights._
-
-5. Facing points to be avoided as far as possible, but when they
-cannot be dispensed with they must be placed as near as practicable to
-the levers by which they are worked or bolted. The limit of distance
-from levers working points to be 180 yards in the case of facing
-points, and 300 yards in the case of trailing points on the main line,
-or safety points of sidings.
-
-[Illustration: Fig. 9.]
-
-In order to ensure that the points are in their proper position before     22
-the signals are lowered, and to prevent the signalman from shifting
-them while a train is passing over them, all facing points must be
-fitted with facing-point locks and locking-bars, and with means for
-detecting any failure in the connections between the signal-cabin and
-points. The length of the locking-bars to exceed the greatest
-wheel-base between any two pairs of wheels of the vehicles in use on
-the line, and the stock rails to be tied to gauge with iron or steel
-ties. All points, whether facing or trailing, to be worked or bolted
-by rods, and not by wires, and to be fitted with double
-connecting-rods.
-
-6. The levers by which points and signals are worked to be interlocked
-and, as a rule, brought close together, into the position most
-convenient for the person working them, in a signal-cabin or on a
-properly constructed stage. The signal-cabin to be commodious, and to
-be supplied with a clock, and with a separate block instrument for
-signalling trains on each line of rails. The point-levers and
-signal-levers to be so placed in the cabin that the signalman when
-working them shall have the best possible view of the railway, and the
-cabin itself to be so situated as to enable the signalman to see the
-arms and the lights of the signals and the working of the points. The
-back lights of the signal lamps to be made as small as possible,
-having regard to efficiency, and when the front lights are visible to
-the signalman in his cabin no back lights to be provided. The fixed
-lights in the signal-cabin to be screened off, so as not to be
-mistakable for the signals exhibited to control the running of trains.
-If, from any unavoidable cause, the arm and light of any signal cannot
-be seen by the signalman they must, as a rule, be repeated in the
-cabin.
-
-7. The interlocking to be so arranged that the signalman shall be
-unable to lower a signal for the approach of a train until after he
-has set the points in the proper position for it to pass; that it
-shall not be possible for him to exhibit at the same moment any two
-signals that can lead to a collision between two trains; and that,
-after having lowered the signals to allow a train to pass, he shall
-not be able to move any points connected with, or leading to, the line
-on which the train is moving. Points also, if possible, to be so
-interlocked as to avoid the risk of a collision.
-
-[Illustration: Fig. 10.]
-
-Home or starting signals next in advance of trading-points when            24
-lowered, to lock such points in either position, unless such locking
-will unduly interfere with the traffic.
-
-A distant signal must not be capable of being lowered unless the home
-and starting signals in advance of it have been lowered.
-
-8. Sidings to be so arranged that shunting operations upon them shall
-cause the least possible obstruction to the passenger lines.
-Safety-points to be provided upon goods and mineral lines and sidings,
-at their junctions with passenger lines, with the points closed
-against the passenger lines and interlocked with the signals.
-
-9. When a junction is situated near to a passenger station, the
-platforms to be so arranged as to prevent, as far as possible, any
-necessity for standing trains on the junction.
-
-10. The junctions of all single lines to be, as a rule, formed as
-double-line junctions.
-
-11. The lines of railway leading to the passenger platforms to be
-arranged so that the engines shall always be in front of the passenger
-trains as they arrive at and depart from a station; and so that, in
-the case of double lines, or of passing places on single lines, each
-line shall have its own platform. At terminal stations a double line
-of railway must not end as a single line.
-
-12. Platforms to be continuous, and not less than 6 feet wide for
-stations of small traffic, nor less than 12 feet wide for important
-stations. The descents at the ends of the platforms to be by ramps,
-and not by steps. Pillars for the support of roofs and other fixed
-works not to be less than 6 feet from the edges of the platforms. The
-height of the platforms above rail level to be 3 feet, save under
-exceptional circumstances, and in no case less than 2 feet 6 inches.
-The edges of the platforms to overhang not less than 12 inches. As
-little space as possible to be left between the edges of the platforms
-and those of the footboards on the carriages. Shelter to be provided
-on every platform, and conveniences where necessary. Names of stations
-to be shown on boards and on the platform lamps.
-
-13. When stations are placed on, or near a viaduct, or bridge under
-the railway, a parapet or fence on each side to be provided of
-sufficient height to prevent passengers, who may by mistake leave the
-carriages when not at the platform, from falling from the viaduct or
-bridge in the dark.
-
-[Illustration: Fig. 11.]
-
-14. Footbridges or subways to be provided for passengers to cross the      26
-railway at all exchange and other important stations. Staircases or
-ramps leading to or from platforms to be at no point narrower than at
-the top, and the available width to be in no case contracted by any
-erection or fixed obstruction whatever below the top.
-
-At all stations where crowding may be expected, the staircases or
-ramps to be of ample width, and barriers for regulating the entrance
-of the crowd at the top to be erected. If in such cases there are
-gates at the bottom, a speaking-tube or other means of communication
-between the top and bottom to be provided; and in all cases gates at
-the bottom of a staircase or ramp to open outwards. For closing the
-openings at the top, sliding bars or gates are considered best.
-
-The steps of staircases to be never less than 11 inches in the tread,
-nor more than 7 inches in the rise, and midway landings to be provided
-where the height exceeds 10 feet.
-
-Efficient handrails to be provided on both staircases and ramps, and
-in subways where ramps are used the inclination not to exceed 1 in 8.
-
-15. A clock to be provided at every station, in some conspicuous
-position visible from the platforms.
-
-16. No station to be constructed, and no siding to join a passenger
-line, on a steeper gradient than 1 in 260, except where it is
-unavoidable. When the line is double, and the gradient at a station or
-siding-junction is necessarily steeper than 1 in 260, and when danger
-is to be apprehended from vehicles running back, a catch-siding with
-points weighted for the siding, or a throw-off switch, to be provided
-to intercept runaway vehicles at a distance outside the home-signal
-for the ascending line, greater than the length of the longest train
-running upon the line.
-
-Under similar circumstances, when the line is single, provision for
-averting danger from runaway vehicles to be made--
-
-  (1) At a station in one of the following manners:--
-
-     (_a_) A second line to be laid down, a second platform to be
-     constructed, and a catch-siding or throw-off switch to be
-     provided on the ascending line inside the loop-points.
-
-     (_b_) A loop-line to be constructed lower down the incline than
-     the station platform with a similarly placed catch-siding or
-     throw-off switch.
-
-  (2) At a siding-junction in one of the following manners, except where   27
-  it is possible to work the traffic with the engine at the lower end
-  of a goods or mineral train, in which case an undertaking (see No.
-  35) to do so, given by the company, will be accepted as sufficient:--
-
-     (_a_) A similar loop to be constructed as in the case of a
-     station.
-
-     (_b_) Means to be provided for placing the whole train on sidings
-     clear of the main line before any shunting operations are
-     commenced.
-
-17. Engine-turntables of sufficient diameter to enable the longest
-engines and tenders in use on the line to be turned without being
-uncoupled to be erected at terminal stations and at junctions and
-other places at which the engines require to be turned, except in
-cases of short lines not exceeding 15 miles in length, where the
-stations are not at a greater distance than 3 miles apart, and the
-railway company gives an undertaking (see No. 35) to stop all trains
-at all stations. Care to be taken to keep all turntables at safe
-distances from the adjacent lines of rails, so that engines, waggons,
-or carriages, when being turned, may not foul other lines or endanger
-the traffic upon them.
-
-18. Cast-iron must not be used for railway under-bridges, except in
-the form of arched-ribbed girders, where the material is in
-compression.
-
-In a cast-iron arched bridge, or in the cast-iron girders of an
-over-bridge, the breaking weight of the girders not to be less than
-three times the permanent load due to the weight of the
-superstructure, added to six times the greatest moving load that can
-be brought upon it.
-
-In a wrought-iron or steel bridge, the greatest load which can be
-brought upon it, added to the weight of the superstructure, not to
-produce a greater strain per square inch on any part of the material
-than five tons where wrought-iron is used, or six tons and a half
-where steel is used.
-
-The engineer responsible for any steel structure to forward to the
-Board of Trade a certificate to the effect that the steel employed is
-either cast-steel, or steel made by some process of fusion,
-subsequently rolled or hammered, and of a quality possessing
-considerable toughness and ductility, together with a statement of all
-the tests to which it has been subjected.
-
-19. In cases where bridges or viaducts are constructed wholly or           28
-partially of timber, a sufficient factor of safety, depending on the
-nature and quality of the timber, to be provided for.
-
-_N.B.--The heaviest engines, boiler trucks, or travelling cranes in use
-on railways afford a measure of the greatest moving loads to which a
-bridge can be subjected. The above rules apply equally to the main
-transverse girders and rail-bearers._
-
-20. It is desirable that viaducts should, as far as possible, be
-wholly constructed of brick or stone, and in such cases they must have
-parapet walls on each side, not under 4 feet 6 inches in height above
-the rail level, and not less than 18 inches thick.
-
-Where it is not practicable to construct the viaducts of brick or
-stone, and iron or steel girders are made use of, it is considered
-best that in important viaducts the permanent way should be laid
-between the main girders. In all cases substantial parapets, with a
-height of not less than 4 feet 6 inches above rail-level must be
-provided by an addition to the girders, unless the girders themselves
-are sufficiently high. On important viaducts where the superstructure
-is of iron, steel, or timber, substantial outside wheel-guards to be
-fixed above the level of, and as close to the outer rails as possible,
-but not so as to be liable to be struck by any part of an engine or
-train running on the rails.
-
-In the construction of the abutments or piers which support the
-girders of high bridges and viaducts, cast-iron columns of small size
-must not be used.
-
-In all large structures a wind-pressure of 56 lbs. per square foot to
-be assumed for the purpose of calculation, which will be based on the
-rules laid down in the report, dated 30th May, 1881, of the committee
-appointed by the Board of Trade to consider the question of
-wind-pressure on railway structures.
-
-21. The upper surfaces of the wooden platforms of bridges and viaducts
-to be protected from fire.
-
-22. All castings for use in railway structures to be, where
-practicable, cast in a similar position to that which they are
-intended to occupy when fixed.
-
-23. The joints of rails to be secured by means of fish-plates, or by
-some other equally secure fastening. On main lines, and lines where
-heavy traffic may be worked at high speed, the chairs not to weigh
-less than 40 lbs.; but on branch lines, or lines on which the traffic      29
-is light, chairs weighing not less than 30 lbs. may be used.
-
-24. When chairs are used to support the rails they must be secured to
-the sleepers, at least partially, by iron spikes or bolts. With
-flat-bottomed rails, when there are no chairs, or with bridge rails,
-the fastenings at the joints, and at some intermediate places, to
-consist of fang or other through-bolts; and such rails, on curves with
-radii of 15 chains or less, to be tied to gauge by iron or steel ties
-at suitable intervals.
-
-25. In any curve where the radius is 10 chains or less, a check-rail
-to be provided.
-
-26. Diamond-crossings, as a rule, not to be flatter than 1 in 8.
-
-27. No standing work (other than a passenger platform) to be nearer to
-the side of the widest carriage in use on the line than 2 feet 4
-inches, at any point between the level of 2 feet 6 inches above the
-rails, and the level of the upper parts of the highest carriage doors.
-This applies to all arches, abutments, piers, supports, girders,
-tunnels, bridges, roofs, walls, posts, tanks, signals, fences, and
-other works, and to all projections at the side of a railway
-constructed to any gauge.
-
-28. The intervals between adjacent lines of rails, where there are two
-lines only, or between lines of rails and sidings, not to be less than
-6 feet. Where additional running lines of rails are alongside the main
-lines, an interval of not less than 9 feet 6 inches to be provided, if
-possible, between such additional lines and the main lines.
-
-29. At all level crossings of public roads, the gates to be so
-constructed that they may be closed either across the railway, or
-across the road at each side of the crossing, and a lodge, or, in the
-case of a station, a gatekeeper’s box, to be provided, unless the
-gates are worked from a signal cabin. The gates must not be capable of
-being opened at the same time for the road and the railway, and must
-be so hung as not to admit of being opened outwards towards the road.
-Stops to be provided to keep the gates in position across the road or
-railway. Wooden gates are considered preferable to iron gates, and
-single gates on each side to double gates. Red discs, or targets, must
-be fixed on the gates, with lamps for night use, and semaphore signals
-in one or both directions interlocked with the gates, may be required.
-At all level crossings of public roads or footpaths, a footbridge or a
-subway may be required.
-
-At occupation and field crossings, the gates must be kept hung so as       30
-to open outwards from the line.
-
-30. Sidings connected with the main lines near a public road level
-crossing to be so placed that shunting may be carried on with as
-little interference as possible with the level crossing; and, as a
-rule, the points of the sidings to be not less than 100 yards from the
-crossing.
-
-31. At public road level crossings in or near populous places, the
-lower portions of the gates to be either close barred, or covered with
-wire netting.
-
-32. Mile posts, half-mile, and quarter-mile posts, and gradient-boards
-to be provided along the line.
-
-33. Tunnels and long viaducts to be in all cases constructed with
-refuges for the safety of platelayers. On under-bridges without
-parapets, handrails to be provided. Viaducts of steel, iron, or timber
-to be provided with manholes or other facilities for inspection.
-
-34. Continuous brakes (in accordance with the Regulation of Railways
-Act of 1889), complying with the following requirements, to be
-provided on all trains carrying passengers, viz.--
-
-     (1) The brake must be instantaneous in action, and capable of
-     being applied by the engine-driver and guards.
-
-     (2) The brake must be self-applying in the event of any failure
-     in the continuity of its action.
-
-     (3) The brake must be capable of being applied to every vehicle
-     of the train, whether carrying passengers or not.
-
-     (4) The brake must be in regular use in daily working.
-
-     (5) The materials of the brake must be of a durable character,
-     and easily maintained and kept in order.
-
-35. Any undertaking furnished by a railway company to be under the
-seal, and signed by the chairman and secretary of the company.
-
-
-Recommendations as to the Working of Railways.--1. There should
-be a brake vehicle, with a guard in it, at or near the tail of every
-passenger train; this vehicle should be provided with a raised roof
-and extended sides, glazed to the front and back, and it should be the
-duty of the guard to keep a constant look-out from it along his train.
-
-2. All passenger carriages should be provided with continuous
-footboards, extending the whole length of each carriage and as far as      31
-the outer ends of the buffer castings. As passenger carriages pass
-from one company’s line to another’s, it is essential for the public
-safety that, although the widths of the carriages on the different
-lines may differ from each other, the widths across the carriages from
-the outside of the continuous footboard on one side, to the outside of
-the continuous footboard on the opposite side, should be identical for
-the carriages of all railway companies, so that the lines of rails may
-be laid at the proper distance from the edges of the passenger
-platforms.
-
-3. There should be efficient means of communication between the guard,
-or guards, of every passenger train and the engine-driver, and between
-the passengers and the servants of the company in charge of the train.
-
-4. The tyres of all wheels should be so secured as to prevent them
-from flying open when they are fractured.
-
-5. The engines employed with passenger trains should be of a steady
-description, with not less than six wheels, with the centre of gravity
-in front of the driving-wheels, and with the motions balanced. They
-should, as a rule, be run chimney in front.
-
-6. Records should be carefully kept of the work performed by the
-wearing parts of the rolling stock, to afford practical information in
-regard to them, and to prevent them from being retained in use longer
-than is desirable.
-
-7. In addition to the block-telegraph instruments, it is desirable
-that there should be speaking-instruments, or telephones, for
-communication between signalmen, and books for recording the running
-of the trains.
-
-8. When drovers or other persons are permitted to travel with goods or
-cattle trains, suitable vehicles should be provided for their
-accommodation.
-
-9. It is considered that, in fixed signals, the front lights should
-show--
-
-      Green, for all right;
-      Red, for danger;
-
-and that back lights, visible only when the signals are at danger,
-should show white.
-
-10. Refuge sidings should be provided at all main-line stations where
-slow trains are liable to be shunted for fast trains to pass them. If
-at such stations it is impossible to provide refuge sidings, and slow      32
-trains have to be shunted from one main line to the other to allow of
-fast trains passing them, some simple arrangements should be supplied
-in the signal cabins to help to remind the signalman of the shunted
-train.
-
-11. Efficient means should be adopted to prevent the accidental
-opening of the doors of passenger trains.
-
-       *     *     *     *     *
-
-To carry out the undertaking, the engineer has to prepare working
-plans and sections to a somewhat larger scale than that adopted for
-the Government or Parliamentary plans, and on which must be marked the
-exact positions of the commencement of the curves, straight lines, and
-gradients. The sites of all the over and under bridges must be shown,
-and their angles of crossing noted. All road, river, or stream
-diversions must be indicated, so that the work in connection with them
-may be laid out on the ground. All culverts and drains must be marked,
-and their size, depth, and direction described. Public road
-level-crossings, and farm or occupation-road crossings, must be shown
-in their proper positions.
-
-The face-lines of the ends of all tunnels should be marked on the
-working plan and section, and the position of any shafts, which may be
-intended either for use in carrying on the work or for future
-ventilation.
-
-A considerable amount of investigation and negotiation will have to be
-entered into before the locating of the above works can be finally
-decided. The desire to meet the wishes and convenience of all parties
-interested must of necessity be controlled by the physical
-circumstances of each case; very little alteration can be made in the
-level of the rails, although some variation may be made in their
-position.
-
-When fixing the depths of culverts and drains, attention must be paid
-to any probable improvement in the drainage of the district, which
-might at some future time necessitate the deepening of such of the
-main culverts where the inverts had been laid too high.
-
-Unless all these details are determined, and shown on the
-working-plans before the works are commenced, there is the risk that
-embankments may have to be opened out to admit of bridges and
-culverts, and cuttings changed to permit of road diversions.
-
-The entire centre-line of railway must be carefully staked out by          33
-driving strong wooden pegs into the ground at the end of every chain
-length, and along the course of these pegs the longitudinal section
-must be taken. Three pegs, one on each side of the centre peg, are
-generally placed at the commencement and termination of the curves.
-When the longitudinal section has been plotted to scale, and the
-course of the gradients and level portions worked out and drawn on,
-then the heights of the ground level and formation level can be marked
-at each chain, and from them the depths of the cutting and the heights
-of the embankments can be ascertained and marked at each chain. In
-addition to the longitudinal section, it will be necessary to take a
-large number of transverse or cross sections at those pegs, or
-intermediate points, where the ground is at all side-lying or
-irregular. These cross-sections are necessary to determine the
-side-widths, or distances to outer edge of slopes in cuttings or
-embankments, and also to calculate the actual quantity of earthwork to
-be executed. For convenience in taking out the quantities, these
-cross-sections are generally plotted to a natural scale, that is to
-say, to the same scale horizontal as vertical, as shown in the example
-of cross-sections, Figs. 15 to 24. It is also necessary to obtain
-information, by boring or otherwise, as to the material of which the
-cuttings are composed, whether clay, gravel, or rock.
-
-In laying out lines through fairly level plains and populous
-districts, the absence of great natural obstacles will allow the
-engineer to carefully consider how far it may be prudent to diverge to
-the right or to the left, to accommodate towns and places which would
-be excluded by a more direct through route. There will be ample range
-for selection, and it will be rather the question of policy than
-compulsion which will guide him in the route to be taken.
-
-[Illustration: Fig. 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24]
-
-When, however, the locating passes from the lower ground, away up
-amongst the hills and mountain ranges, it becomes an intricate study
-whether it will be possible to lay out any line at all which may
-possess gradients and curves practicable for railway working. The
-question of property, population, or convenience of access, is here no
-longer the controlling influence, but in its stead there are the far
-more formidable natural difficulties to be overcome in working out a
-trackway to the inevitable summit level. The chief endeavour will be
-to gain length, and so reduce as much as possible the steepness of the
-gradients which at the best must necessarily be severe. In some of the     35
-earlier mountain lines constructed abroad the system of _zigzags_ was
-introduced, as shown in Fig. 25. These _zigzags_ were laid out on
-ruling gradients, one above the other, on the sides of the mountain
-slopes with pieces of level at the apices, A, B, and C, on which
-the engine could be changed from one end of the train to the other.
-Although feasible in principle, the system entailed considerable loss
-of time in train-working, and was not unattended with risk.
-
-The more modern and simple method of working out the same idea is to
-connect the main zigzag lines by curves or _spirals_, thus rendering
-the route continuous and unbroken. By this arrangement the heavy work
-and delay in starting or stopping the train at the apices, A, B,
-and C, as shown on Fig. 25, is avoided, and the train can proceed
-continuously on its circuitous journey. Fig. 26 shows an instance of
-the zigzags and spirals, as carried out on an important railway
-abroad. To have made a direct line from D to E, the most difficult
-part of the route, would have involved a gradient of 1 in 11; but by
-constructing the spiral course, as shown, the length was more than
-trebled, and the gradient reduced to 1 in 35.
-
-Fig. 27 is another example of spiral zigzags in which advantage was
-taken to cut a short tunnel through a high narrow neck of rock at
-G, and then by skirting round the hill the line was taken over the
-top of the tunnel and along the side of the mountain to the summit tunnel
-at H. By this means the line from F to H was laid out to an
-average gradient of 1 in 42.
-
-Fig. 28 shows the Cumbres inclines on the Mexican Railway. The route
-had to be located through one of the rugged passes of the great Chain
-of the Andes, whose mountain-sides rise most abruptly from the lower
-plains, to the great upper-land plateau, some eight thousand feet
-above sea-level. The ground to be traversed was so steep and difficult
-that, even with the best available detours and greatest length that
-could be obtained, the result was an average continuous gradient of 1
-in 25 for 12 miles.
-
-[Illustration: Fig. 25, 26, 27, 28, 29]
-
-Fig. 29 is a plan of part of the St. Gothard Railway, showing the
-principal tunnel 9¼ miles long, and some of the adjoining spiral
-tunnels. The long tunnel through the great Alpine barrier was the only
-means of forming a railway connection between the two points at Airolo
-and Goeschenen. Constructed in a straight line, with easy gradients,       37
-falling towards the entrances, efficiency of drainage has been
-secured, and excessive strain on motive-power avoided. The approaching
-valleys on each side were in some places too irregular and broken to
-admit of zigzag loops, and the spiral tunnels were adopted instead.
-The enlarged plan of two of the spiral tunnels will explain the method
-of working. An ascending train enters the first tunnel at A, and
-after passing round almost an entire circle, on a rising gradient,
-emerges at a much higher level at the point B. Proceeding onward,
-the train enters the second tunnel at C, and after passing round a
-similar circle, on a rising gradient, comes out at a still higher
-point, D, and continues its course up the valley.
-
-The last five sketches illustrate some of the methods which have been
-adopted when constructing railways through some of the most difficult
-mountain ranges. They show what has been done, and may serve as guides
-in working out the location of a line in some hitherto unexplored
-region.
-
-
-Gauge.--The gauge of a railway, or its width from inside to inside
-of rails, affects both its cost and efficiency. If the gauge be
-exceptionally wide, then the expenditure on works and rolling-stock
-will be proportionately heavy; and although theoretically the extra
-wide gauge may possess greater capabilities for accommodation and
-high-speed travelling, we may find in practice that the necessary
-requirements may be provided on a much more moderate gauge. On the
-other hand, if the gauge be exceptionally narrow, there will be
-diminished convenience both for passengers and merchandise, and a
-corresponding limit to the speed in transit.
-
-In isolated districts, where passenger traffic is of secondary
-importance, and where the principal merchandise will be heavy without
-being bulky, such as mineral ores, slates, etc., a comparative narrow
-gauge may possibly suit the purpose. For main trunk lines, however,
-where a large, heavy, and fast passenger traffic will have to be
-worked, and where goods of all kinds, many of them bulky without being
-heavy, will have to be carried, an ample gauge must be selected to
-ensure convenience and safety. A liberal gauge permits the use of
-commodious rolling-stock without any great amount of lateral
-overhanging weight outside the wheels; whereas with a narrow gauge
-there is the tendency--if not the necessity--to use vehicles which have
-too great a lateral overhang for proper stability, except at very          38
-moderate speeds.
-
-The following list shows the gauges adopted in various countries:--
-
-                     ft. ins.
-  England, Scotland,
-    and Wales        4   8½
-  Ireland            5   3
-  United States      4   8½, with some lines 5 ft., 5 ft. 6 ins., and 6 ft.
-  Canada             4   8½  and 5 ft. 6 ins.
-  France             4   8½
-  Belgium            4   8½
-  Holland            4   8½
-  Germany            4   8½
-  Austria            4   8½
-  Switzerland        4   8½
-  Italy              4   8½
-  Turkey             4   8½
-  Hungary            4   8½
-  Denmark            4   8½
-  Norway             4   8½ and 3 ft. 6 ins.
-  Sweden             4   8½
-  Mexico             4   8½ and 3 ft.
-  Egypt              4   8½ and 3 ft. 6 ins.
-  Peru               4   8½
-  Nova Scotia        4   8½ and 5 ft. 6 ins.
-  New South Wales    4   8½
-  Brazil             4   8½, 5 ft. 3 ins., and 5 ft. 6 ins.
-  Uruguay Republic   4   8½
-  Russia             5   0
-  South Australia    5   3
-  New Zealand        3   6
-  British India      5   6 and 1 metre.
-  Ceylon             5   6
-  Spain              5   6
-  Portugal           5   6
-  Chili              5   6
-  Argentine Republic 5   6
-  Cape Colonies      3   6
-  Japan              3   6
-
-After many years’ experience of actual working, the broad, 7 feet,
-gauge of the Great Western Railway has been abandoned for the 4 feet
-8½ inch gauge. Doubtless this decision was the result of most careful
-deliberation, and was made upon convincing proof that the 4 feet 8½
-inch gauge could fulfil all the advantages claimed for the wider
-gauge, whilst at the same time it possessed the merit of less cost of
-construction and working, and greater facilities for the exchange of
-traffic with other lines having the standard gauge. The facility of
-exchange, or through working of rolling-stock, is a leading element of
-successful railway working, and it is difficult to estimate what would
-be the amount of loss and delay if we had any great extent of break of
-gauge on the main trunk lines of our own country.
-
-Although some countries have selected gauges of 5 feet and 5 feet          39
-6 inches, it is interesting to note that the largest number have
-adopted the English standard gauge of 4 feet 8½ inches, and that the
-miles of line laid to this gauge far outnumber all the others. The
-fact that our own home lines, the principal Continental lines, and
-nearly all that vast network of railways in the United States of
-America, have been laid to the 4 feet 8½ inch gauge, testifies to the
-general opinion of its utility and efficiency; and we know that
-included in that list are the railways which carry the largest,
-heaviest, and fastest train service in the world.
-
-It would be interesting to trace back, and, if possible, ascertain
-from whence the exact gauge of 4 feet 8½ inches was derived. No doubt,
-in the early days of the pioneer iron highways in England, the
-railways were made the same gauge as the tramroads which they
-superseded. But why was 4 feet 8½ inches the gauge of the tramroads?
-We may reasonably infer that the first four-wheeled waggons used on
-the early tramroads were in reality the same waggons which had been
-previously used on the common roads for the conveyance of coal and
-minerals to the ports for shipment, and that the waggons were merely
-transferred from the roughly paved or macadamised roads to the
-tramroads. Flanged wheels were then unknown, and the introduction of
-the tram-plates was at first simply designed to lessen the resistance
-to haulage. The gauge, or width between the wheels, of these waggons
-may have been the outcome of long experience as to the most suitable
-width for convenience of load, stability during transit, or for space
-occupied on the highway. The width may have been handed down from
-generation to generation, going back to the time when wheeled vehicles
-were first built in the country. Perhaps in the beginning the first
-vehicles may have been imported from Italy, or Greece--countries which
-in the earlier ages were the most advanced in matters of luxury and
-convenience.
-
-When in Pompeii, a few years ago, the writer measured the spaces
-between a large number of the _wheel-ruts_ which are worn deep
-into the paving-stones in many of the principal streets of that
-wonderful unearthed city. These paving-stones, very irregular in
-shape, and many of them 2 feet 6 inches long by 1 foot 6 inches wide,
-are carefully fitted together, and form a compact massive pavement
-from curbstone to curbstone. The wheel-tracks, which are in many
-places worn into the stones to the depth of an inch or an inch and a       40
-half, are always distinct, and there is no difficulty in defining the
-corresponding track.
-
-The result of a large number of measurements gave an average width of
-about 4 feet 11 inches from centre to centre of the wheel-tracks, a
-curious coincidence with the gauge of our own road vehicles at the
-beginning of the railway era. Whether our selection of the railway
-gauge of 4 feet 8½ inches has been the result of study, imitation, or
-caprice, we certainly have the silent testimony of these old deep-worn
-stones to prove that two thousand years ago the chariots of Pompeii
-were of very similar gauge to our own of modern times.
-
-Narrow-gauge railways, of gauges varying from 1 foot 10½ inches on the
-Festiniog Railway, to 3 feet, 3 feet 3 inches (metre), and 3 feet 6
-inches, have been made in several places both at home and abroad.
-Generally speaking, they have been constructed as subsidiary or
-auxiliary lines in thinly populated districts, with a view to afford
-some railway accommodation where it was considered that lines of the
-standard gauge would not pay. In some instances abroad long lines of
-narrow gauge--3 feet and 3 feet 6 inches--have been constructed as
-main trunk lines in newly opened out districts. Some of these have
-since been altered to a wider gauge as the traffic developed, and
-experience proved that the narrow width of the vehicles was unsuitable
-for quick transit, or convenience in the accommodation of passengers
-and goods.
-
-The object in making a line to a narrow gauge is doubtless to save
-cost in the original construction; but when a scheme for an altered
-gauge is put forward, it will be well to consider what amount of
-advantage or saving would be effected by deviating from the standard
-gauge.
-
-If there be almost a certainty that such proposed line will always
-remain isolated from all other existing railways of the standard
-gauge, then perhaps the selection of gauge may be one of minor
-importance, and there remains but the question whether the description
-of traffic, and the weights to be carried, can be worked to any
-greater advantage, or more economically, by deviating from the
-standard gauge.
-
-If, however, there be a fair probability that such proposed line may
-at some future time become part of an already established railway
-system, it would appear to be more prudent to make the line to the
-standard gauge, and effect economies by introducing steeper gradients,     41
-sharper curves, and lighter permanent way, and keep down working
-expenses by using lighter locomotives, worked at slower speeds.
-
-High speeds are not expected on narrow gauge railways, and no
-complaints are made about passenger trains whose highest running speed
-does not exceed 20 miles per hour. By conceding the same indulgence to
-light railways made to the standard gauge, great economies might be
-introduced both in their construction and working. The similarity of
-gauge would admit the transit of the carriages and waggons of other
-standard gauge lines, and so avoid all cost and delay in transshipment.
-The heavy engines could be kept for the main-line working, and light
-engines for slow speeds would serve for the light standard-gauge
-lines. As traffic developed, and the train service required heavier
-and faster trains, the light rails could be removed, and replaced by
-those of heavier section to correspond to the main line. The
-similarity of gauge would permit uninterrupted transit of all vehicles
-to a common centre for repairs, whereas the narrow gauge carriages and
-waggons, being limited to running only on their own district, must
-have separate workshops for their repair.
-
-When considering the cost of construction and working of a
-narrow-gauge railway as compared with one of the standard gauge, there
-are certain items which are common to both, and in which the narrow
-gauge could not be expected to obtain any advantage over the standard
-gauge.
-
-There would not be any saving in getting up the scheme in the first
-instance;
-
-  Nor in the Parliamentary expenses;
-  Nor in the engineering or carrying out of the works;
-  Nor in the station accommodation, waiting-rooms, and offices;
-  Nor in the signals and interlocking arrangements;
-  Nor in the telegraph;
-  Nor in the working staff and train men;
-
-Nor in the maintenance of the permanent way, as the same number of men
-would be required for the inspection and packing of the road, perhaps
-more.
-
-Little or no saving could be expected in the bridges under the
-railway, as these must be made to the prescribed widths and heights,
-irrespective of the gauge of the railways.
-
-Little, if any, saving could be made in river or stream bridges, as the    42
-same amount of waterway would have to be provided in each case.
-
-The same remark applies to culverts and drains.
-
-There would, on the other hand, be a small saving in the quantity of
-land to be acquired to the extent of a narrow strip or zone,
-represented by the difference in width between the narrow and standard
-gauges.
-
-There would also be the same small proportionate saving in the
-embankments and cuttings to the extent of the difference in gauge.
-
-Also a saving in the overline bridges and road approaches in
-consequence of less width and height of the opening through those
-bridges.
-
-And a saving in the rails, sleepers, and ballast of the permanent way,
-to the extent consistent with efficiency. That some saving may be
-effected in these is undoubted, but it is necessary to exercise
-caution, and not rush to the opposite extreme by making the parts too
-light. A rail should be made not only strong enough to carry well the
-engines that have to pass over it, but it should also be heavy enough
-to stand the wear of several years. Narrow-gauge engines must be heavy
-in conformity with the loads they have to haul. The same amount of
-power must be exerted to haul a hundred tons on a given gradient,
-whether the gauge be narrow or broad. In some cases of narrow-gauge
-railways the original rails, which weighed only 45 lbs. per yard, have
-since been replaced with others weighing 60 and 65 lbs. per yard. The
-light 45 lb. rails were evidently not found to be sufficiently heavy
-to keep the road to proper line and level. The result of our everyday
-practice seems to prove that there is not only an advantage, but an
-economy, in adopting rails of a heavy section, and experience would
-therefore indicate that even for a narrow-gauge railway it may not be
-expedient to adopt rails weighing less than 65 lbs. per yard.
-
-
-Gradients.--There are very few localities where the rails on any
-line of railway can be laid perfectly level or horizontal for more
-than comparatively short distances. By far the greater portion have to
-be laid on inclined planes of varying rates of inclination to suit the
-general formation of the district traversed, and the circumstances of
-the line to be constructed.
-
-The degree, or rate of inclination, of these inclined planes, or
-gradients, may be expressed in various ways. A very general method is      43
-to state the number of feet, metres, etc., which can be measured along
-the gradient before an increased rise or fall of one foot or metre,
-etc., is obtained. Thus a gradient of 1 in 200 signifies a rise or
-fall of 1 foot in 200 feet, or 1 metre in 200 metres.
-
-Sometimes the rate of inclination is expressed by stating the number
-of feet of rise or fall in a mile. In this way a gradient would be
-described as falling at the rate of 30 feet in a mile, rising at the
-rate of 20 feet in a mile, etc. Twenty feet to a mile is equal to 1 in
-264.
-
-Another method is to give the percentage of rise or fall. In this way
-the inclination would be expressed as a 1 per cent. gradient, 2 per
-cent. gradient, ½ per cent. gradient, etc., which for comparison would
-signify 1 in 100, 1 in 50, and 1 in 200 respectively.
-
-The gradients of a railway most materially influence its facility and
-cost of working, and every effort should be used to make them as easy
-as possible consistent with the prospect of the line.
-
-Steep gradients signify heavy locomotives, increased cost of
-motive-power, reduced speed, and light loads.
-
-The following tabulated memoranda show the approximate loads,
-exclusive of engine and tender, which can be hauled on the level and
-on certain inclines at various speeds by engines of the quoted
-capacities and steam admissions. A medium-sized, ordinary type of
-passenger and goods engine has been selected for each of the examples.
-The working of the passenger engine and train is assumed to be under
-favourable circumstances, with fine weather, fairly straight line,
-first-class permanent way, modern rolling-stock with oil axle-boxes
-and perfect lubrication, and all the conditions most suitable to
-ensure the least resistance to the moving load. For the goods engine
-and train a greater resistance per ton of load is assumed, as the
-goods trucks are never so perfect or easy in the running as the
-passenger carriages. A certain amount of side wind is taken into
-consideration, and also an allowance for moderately sharp curves, the
-object being to indicate what may be looked upon as fair, average,
-workable loads.
-
-The loads for engines of larger or smaller dimensions, or higher or
-lower pressures, may be obtained by working out the proportion between     44
-the tractive force put down in any of the columns of the tabulated
-memoranda and the ascertained tractive force of any other engine under
-the same conditions of cut-off and speed.
-
-  -----------------------+-------------------------+-------------------------
-                         |   PASSENGER ENGINE.     |      GOODS ENGINE.
-                         |                         |
-                         |Six wheels, driving      |Six wheels, all coupled,
-                         | and trailing wheels     | 4 ft. 6 ins. diameter.
-                         | coupled, 6 ft. 6 ins.   | Cylinders,
-                         | diameter. Cylinders,    | 17 ft. × 24 ft.
-                         | 17 ft. × 24 ft.         | Locked-down pressure on
-                         | Locked-down pressure on | safety-valves, 140 lbs.
-                         | safety-valves, 140 lbs. | per square inch. Assumed
-                         | per square inch. Assumed| pressure at cylinders,
-                         | pressure at cylinders,  | 120 lbs. per square inch.
-                         | 120 lbs. per square     |
-                         | inch.                   |
-                         |                         |
-                         |Weight of engine 39 tons.|Weight of engine 34 tons.
-                         |  ”       tender 24  ”   |  ”       tender 24  ”
-                         |                 --      |                 --
-                         |                 63  ”   |                 58  ”
-  -----------------------+-----+-----+------+------+-----+-----+------+------
-  Assumed cut-off        |  ¼  |  ⅓  |  ½   |  ¾   |  ¼  |  ⅓ |   ½  | ¾
-      ”   mean effective |     |     |      |      |     |     |      |
-           pressure, lbs.|  45 |  56 |  76  | 100  |  45 |  56 |  76  | 100
-      ”   tractive force,|     |     |      |      |     |     |      |
-           lbs.          | 4000| 4979| 6758 | 8892 | 5780| 7192| 9760 | 12844
-  Speed in miles per hour|  60 |  40 |  30  |  15  |  40 |  30 |  20  |  15
-                         |     |     |      |      |     |     |      |
-                         |Tons.|Tons.|Tons. |Tons. |Tons.|Tons.|Tons. |Tons.
-                         |     |     |      |      |     |     |      |
-  Level                  |  97 | 230 | 447  | 892  | 213 | 358 | 623  | 907
-  1 in 1000              |  84 | 196 | 373  | 707  | 187 | 310 | 532  | 768
-    ”   800              |  81 | 188 | 358  | 671  | 181 | 299 | 512  | 739
-    ”   600              |  76 | 177 | 335  | 618  | 172 | 285 | 482  | 695
-    ”   400              |  68 | 157 | 296  | 533  | 157 | 257 | 432  | 621
-    ”   300              |  60 | 141 | 263  | 467  | 143 | 233 | 390  | 560
-    ”   250              |  55 | 129 | 241  | 424  | 133 | 216 | 361  | 519
-    ”   200              |  47 | 114 | 213  | 372  | 120 | 195 | 324  | 467
-    ”   150              |  37 |  93 | 177  | 304  | 101 | 165 | 276  | 397
-    ”   100              |  21 |  63 | 126  | 217  |  74 | 123 | 208  | 302
-    ”    90              |  -- |  56 | 114  | 197  |  -- | 113 | 191  | 279
-    ”    80              |  -- |  48 | 101  | 175  |  -- | 101 | 172  | 253
-    ”    75              |  -- |  43 |  94  | 164  |  -- |  95 | 163  | 240
-    ”    70              |  -- |  39 |  86  | 152  |  -- |  88 | 153  | 226
-    ”    60              |  -- |  28 |  70  | 128  |  -- |  74 | 131  | 196
-    ”    50              |  -- |  -- |  53  | 101  |  -- |  -- | 107  | 163
-    ”    40              |  -- |  -- |  --  |  73  |  -- |  -- |  --  | 127
-    ”    25              |  -- |  -- |  --  |  27  |  -- |  -- |  --  |  67
-  -----------------------+-----+-----+------+------+-----+-----+------+------
-
-  NOTE.--The column loads in tons are exclusive of the weight of
-         engine and tender.
-
-From the above memoranda it will be seen how greatly the gradients         45
-affect the loads. For an important main trunk line, with a heavy and
-frequent train-service of passengers and goods, the introduction of
-steep gradients would not only reduce the speed of the train-working,
-but would probably involve the necessity of assistant engines over
-those parts of the line; and it may be prudent, where possible, to
-incur heavier earthworks, or considerable detours, or tunnels, to
-obtain more favourable gradients. For such a line the additional cost,
-and the extra distance caused by a detour of a mile or more, will be
-of far less importance than the interruption in the train service
-arising from a serious reduction in speed or taking on assistant
-engines. On many railways abroad there are very interesting examples
-of long detours of several miles, carefully studied out to obtain
-greater length and easier gradients, resulting in the construction of
-lines over which the traffic can be worked without necessitating
-auxiliary engine-power. On the other hand, there are situations where
-steep gradients cannot be avoided, where certain altitudes must be
-reached, and where there is no alternative but to face the inevitable.
-
-On secondary lines, and short branch lines, where the traffic is not
-expected to be heavy, and where speed is not so important, it may be
-policy to economize outlay and introduce steeper
-gradients than on the main line.
-
-Half a mile of a rather steep gradient is not felt so much when it is
-situate midway between two stations, because the attained speed of the
-train assists the engine over the short distance to the summit; but
-when it occurs as a rising gradient out of a station, it forms a great
-check to the working, particularly in bad or wet weather, when there
-is the risk of the engine slipping, and the entire train sliding back
-into the station.
-
-Long steep gradients not only necessitate increased motive-power for
-the ascending trains, but also require increased brake-power, and
-precautionary measures for the descending trains. Where passenger
-trains are fitted with continuous brakes, the risk of losing control
-is minimized; but with goods trains composed of waggons, having only
-the ordinary independent side-lever brake, it will be found absolutely
-necessary in many cases to have additional heavy brake-vans for
-descending the inclines, and these special vans, unfortunately, will
-form so much extra non-paying weight to be hauled up on the ascending
-trains. Of course, it is quite possible--and, indeed, in many places       46
-it is customary--to pin down some of the side-lever brakes before
-commencing the descent, but once pinned down the brakes cannot be
-eased or taken off until the entire train is brought to a stand.
-
-Every goods waggon should be fitted with a brake, and it would be of
-immense value if that brake could in all cases be applied and
-controlled when the train is in motion.
-
-The American type of long goods waggon, with a four-wheel bogie-truck
-at each end, is fitted with a brake very similar to those adopted on
-the ordinary horse tram-cars. On the top of the waggon a horizontal
-iron hand-wheel, about 18 inches in diameter, is fixed on to a strong
-vertical iron rod, which works in brackets, and extends down below the
-underside of waggon framing. One end of a short length of chain is
-secured to the foot of the vertical rod, and the other end is
-connected by light iron rods to the series of levers which pull on the
-brake-blocks. By rotating the horizontal hand-wheel the chain is
-coiled round the lower end of the vertical rod, the brake-levers are
-pulled over, and brake-pressure applied to the wheels of the waggon.
-The brakesman is supplied with a convenient seat and footboard, and on
-the floor-level of the latter there is a pawl and ratchet attached to
-the vertical rod, which permits the brakes to be applied to the extent
-required. The pawl retains the brakes in position until the brakesman
-with his foot pushes the pawl out of the notch of the rachet and
-releases the brake gearing, which is at once pulled off quite clear by
-strong bow-strings attached to the framework of the bogies.
-
-This type of hand-brake is, perhaps, the simplest that can be made.
-The brakesman has merely to put it on, the pawl and ratchet keep it
-on, and the bow springs take it off when no longer required. Each one
-of these long, loaded goods waggons becomes a very serviceable
-brake-van, and for ascending and descending steep inclines all that is
-necessary is to take on a few additional brakesmen to manage the
-brakes of as many suitable waggons. These incline brakesmen, after
-going down, can return to the summit by the next ascending train,
-their small weight being a mere nothing as compared with that of
-special or extra brake-vans.
-
-On some European lines it is the custom to sprag some of the goods
-waggon wheels when going down exceptionally steep inclines, as well as     47
-applying the brakes on the ordinary and extra brake-vans. The sprag is
-a piece of wood, circular in section, about 2 feet 6 inches long, and
-5 to 6 inches thick in the middle, tapering off to about 2 inches
-thick at the ends. When the waggon-wheel is just beginning to move,
-the sprag is inserted between the spokes, and being caught against the
-waggon framework, the wheel is held fast, and being unable to revolve,
-remains fixed, and acts like a skid upon the rails. The skidding of
-the wheels upon the rails wears flat places on the wheel tyres, and it
-is needless to mention that the practice is only resorted to in very
-extreme cases. Although a very primitive means for checking the speed
-of a descending train, or for maintaining vehicles stationary on an
-incline, there have been many instances where lives have been saved
-and accidents prevented by the prompt use of a few sprags. Solid or
-close wheels cannot be spragged, only wheels which have spokes or
-openings, and for this reason alone it would be very desirable that in
-every passenger and goods train there should be some spoke or open
-wheels which could be spragged as a last resource, in the event of a
-sudden emergency of brakes failing or train becoming divided on an
-incline.
-
-On ascending gradients there is always the risk of a coupling
-breaking, and the train becoming divided. If the detached portion left
-behind be provided with ample brake-power, hand-brakes, or otherwise,
-no harm may take place beyond a little delay; but if the brake-power
-be insufficient or defective, and if all the wheels are solid wheels
-incapable of admitting a few timely sprags, then the vehicles cannot
-be held, but must slide back, and running unchecked would soon attain
-such a velocity as would cause them either to leave the rails or dash
-into another train standing at the last station. Many lamentable
-accidents have taken place arising from portions of trains breaking
-away and running back, and the sad experience of those casualties
-should call forth every effort to avert a recurrence in the future. It
-may not always be possible to detect a hidden flaw in a coupling, or a
-defect in the brake-gearing until the actual failure occurs; but it is
-quite possible to guard against disastrous results from such failure,
-by providing means to hold the vehicles, and prevent them sliding
-back.
-
-For some years the writer had the entire charge of an important
-railway abroad on which the gradients were very exceptional, and where     48
-it was absolutely necessary that he should organize the most complete
-precautions to prevent the possibility of trains, or portions of
-trains, running back down inclines. Starting from sea-level, the line,
-which was laid to the 4 feet 8½ inch gauge, rose to a summit of over
-8000 feet, and on the mountain division there were many long gradients
-of 1 in 40, 1 in 33, and in one place a continuous gradient of 1 in 25
-for 12 miles. The specially powerful engines reserved for these heavy
-inclines were each supplied with an ordinary hand-brake, a
-steam-brake, and a Westinghouse continuous brake. The passenger
-carriages, which were of considerable length, and carried on a
-four-wheeled bogie-truck at each end, were all fitted up with the
-Westinghouse brake, and in addition each carriage had its own
-hand-wheel brake with the pawl and ratchet gearing. All the goods
-waggons, which were of the American type, were fitted with hand-wheel
-brakes similar to those on the carriages. Special gangs of trained
-brakesmen took charge of the trains on these inclines, a brakesman to
-every carriage or waggon, and were always in readiness in case of the
-breakage of a coupling, or the failure in the Westinghouse brake or
-brakes on engine. The immunity from accidents justified the combined
-precautions adopted, and proved the possibility of working such severe
-gradients with perfect safety.
-
-The long-continued application of the brakes on heavy inclines
-naturally leads to the question as to the description of wheel to be
-adopted for the work. Not only are the wheels subjected to very severe
-torsional strains, but the temperature at the circumference is raised
-very high in consequence of the friction. Perhaps, theoretically, the
-safest wheel would be one made out of a solid piece of metal, similar
-to the chilled cast-iron wheels of the United States, or the steel
-disc wheels used on some lines in Europe, in either of which holes can
-be left for sprags. Wheels of this description can withstand very
-heavy wear and tear, they are not affected by increased temperature,
-and they certainly have the minimum of parts to work loose. Of the
-built-up wheels, the strong forged-iron-spoke wheel with steel tyres
-shows excellent results, and always gives due warning of loosening by
-indications at the tyre rivets. The suddenness with which the solid
-wooden centre wheels sometimes break up and fall to pieces does not
-commend them for a service where there must be a long-sustained
-application of the brakes. The increased temperature which expands the     49
-tyre, contracts the wood, and must loosen and weaken the entire wheel.
-
-On all steep gradients the road-bed should be of the most substantial
-character, and the permanent way of a strong description, and
-maintained in perfect order, as the engines for working the traffic
-must necessarily be of a heavy type. The rails will be severely tested
-by the pounding and slipping of the engines on the ascending journey,
-and by the action of the brakes on the descending journey.
-
-In the early days of the railway system, rope-haulage was adopted on
-some of the main lines for working the trains on steep inclines near
-the principal terminal stations. A powerful stationary engine, located
-at the highest point, was employed to work an endless rope which
-passed round large drums at the top and bottom of the incline, and was
-supported on sheaves or pulleys fixed between the rails. The
-connection between the carriages and endless rope was effected by
-means of a short piece of rope called the _messenger_, which was
-coiled round the main rope in such a manner as to be readily detached
-when the train reached the summit. There are many persons who will
-remember the time when the passenger trains were hauled by an endless
-rope up the 1 in 66 incline from Euston to Camden Town, a distance of
-about a mile and a half, and up the 1 in 48 incline from Lime Street,
-Liverpool, to Edge Hill, a distance of about a mile and a quarter, and
-several others. The rapid strides made in locomotive construction, and
-the increased pressure used in the boilers, enabled much more powerful
-engines to be built, until one by one the rope-haulage machinery has
-disappeared from nearly all the inclines where for years it had been
-considered indispensable. Rope-haulage on inclines is now very rarely
-met with, except at collieries and ironworks, where occasionally the
-rope may be seen so arranged that the loaded waggons descending pull
-up the empty waggons on the opposite or parallel line.
-
-
-Curves.--The degree of curvature of a railway curve is generally
-expressed by giving the radius in feet, chains, metres, or other
-national standard measure.
-
-When laying out a line of railway, the natural features of the country
-will necessitate the introduction of curves, and the question for
-consideration will be whether they are to be made of small or large
-radius. In some cases sharp curves are inevitable, except by incurring     50
-enormous works which would not appear to offer any corresponding
-prospective recompense. In others the curves may be made of easy
-radius, at a comparative moderate extra outlay, if the character of
-the line and description of traffic to be accommodated will warrant
-the expenditure. For main through lines, with heavy, high-speed
-traffic, it is advisable to have the curves of large radius, so as to
-avoid the necessity of reducing speed when passing round them.
-Although a high-class fast train may be allowed to run round an 80
-chain (5280 feet) curve at almost unrestricted speed, safety demands
-that there should be a reduction of speed on curves of 40 or 30 chains
-radius, and a very much greater reduction for curves of 20 chains
-radius and under. A sharp curve will in some places form a greater
-check to fast trains than a length of moderately steep gradient on a
-straight line. In the former the trains running in either direction
-must slow down for some distance before reaching the curve, round
-which they should pass at greatly reduced speed, and then some
-distance must be run before they can attain their full speed again. On
-the other hand, with a rising gradient, on a fairly straight line, the
-acquired momentum of the train will materially assist in ascending the
-incline, and although the speed may be slackened as the train
-advances, there may not be any very great diminution in the running
-before the gradient is passed, and average level line reached again. A
-reduced rate of running must be maintained round curves of small
-radius, for, however substantial the works and permanent way, and
-however well devised and constructed the rolling-stock, there is an
-element of danger ever present when passing round sharp curves at
-anything more than moderate speed. In the great rush for fast through
-trains this point is very apt to be overlooked, and too little time
-allowed for the running. Even with the fastest trains on any line
-there are some portions of the route which must be traversed with
-greater caution and less speed than others, either on account of sharp
-curves or of gradients; and if those who are entrusted with the
-preparations of the time tables do not possess the technical
-information necessary to deal properly with the question of relative
-speeds, there is the strong probability that the programme prepared
-may be one both difficult and dangerous to fulfil. The spirit of
-rivalry is a strong incentive to fast running, but prudence and common
-sense should indicate that record speeds should only be attempted on       51
-the straight or favourable portions of the line. There is,
-unfortunately, the growing tendency to run faster and faster round the
-curved portion of our lines, heedless of the close approach to the
-limit of safety, and unless this excessive speed be controlled in
-time, the result must be disaster on a very large scale.
-
-A sharp curve leading into or out of a terminal station or main-line
-stopping-station does not so much affect the train running as a sharp
-curve at an intermediate point between stations where the train may be
-expected to run at its maximum speed. Wherever it is possible it is
-very desirable to avoid sharp curves on inclines, because there are
-times when descending trains may acquire a considerable velocity, and
-wheels tightly gripped by the brakes have not the same facility for
-following the curves as when they are running free.
-
-In rugged and mountainous districts sharp curves are almost
-unavoidable, except by introducing a series of tunnels; but in these
-districts both the gradients and curves are alike exceptional, the
-speed is necessarily slow, and special precautions are taken for the
-ascending and descending trains.
-
-[Illustration: Fig. 30, 31, 32, 33, 34, 35, 36, 37, 38]
-
-When setting out reverse curves on a main line a piece of straight
-line should always be laid in between the termination of the one curve
-and the beginning of the other, to allow of a proper adjustment of the
-rails to suit the super-elevation adopted on each of the adjoining
-curves. In station yards and sidings this is not so absolutely
-necessary, the sorting of the carriages and waggons and the
-marshalling of the trains being carried on at a low speed, which does
-not necessitate any super-elevation of the rails on the curves. The
-speed of the train regulates the amount of super-elevation to be given
-on any particular curve, and to ensure smooth and safe running this
-amount must be maintained uniform all round the curve. On curves of
-small radius, guard, or check, rails are frequently placed alongside
-the inner rail, as in Figs. 30 to 33, to check the tendency of the
-engine to leave the rails and run in a straight line. For the
-bull-head road a special chair is used, which holds both the
-running-rail and the check-rail, as shown on the sketch, the rails
-being kept the proper distance apart by the web portion in the centre,
-which forms part of the casting. For the flange railroad, check-rails
-are sometimes made of strong angle irons placed against the flange of
-the running-rail, and bolted to the transverse sleepers. This method       53
-is not nearly so strong or efficient as the arrangement shown on Fig.
-33, with a cast-iron distance-block about six inches long, placed
-between the running-rail and check-rail, and all tied together with a
-strong through bolt. A bolt-hole is punched in the edge of the flange
-of check-rail, and a crab bolt and clip holds the two rails on the
-sleeper. The cast-iron distance-blocks are placed just outside the
-sleeper, so as not to interfere with the holding-down bolt. Doubtless
-these guard rails do good service, but if the leading wheels of the
-engine have sharp or worn flanges there is the possibility that the
-wheel, pressing against the high rail, may mount the rail, and throw
-the train off the line. A more secure method is to place the guard
-outside the high rail, as in Figs. 34 to 38. This can be done by securing
-a strong continuous longitudinal timber to the cross-sleepers--or to
-the cross-girders in the case of a girder bridge--with its outer or
-striking edge protected with a fairly heavy angle iron. The top of
-this outside guard above the rail level may be three inches or more,
-according to the height of any hanging spring, or portion of brake
-apparatus belonging to the rolling-stock. The distance between the
-striking-face of the guard and the inside of head of rail should be
-about 5 inches, or such width that before the flange of the wheel can
-mount on the top of the rail, the face of the wheel-tyre will be
-brought into contact with the striking-face of the outside guard, and
-thus effectually prevent the wheel leaving the rail. The sketches show
-some of the types applicable to the chair road, and to the flange
-railroad. In Figs. 34, 35, and 37, the outside brackets are of heavy
-angle iron cut off in lengths to correspond to the width of the
-sleeper. In Fig. 36 the cast-iron chair is lengthened, and has an end
-bracket to support the guard timber. In Fig. 37 a hard wood bolster is
-fastened on the top of each sleeper, and on this is placed the
-continuous guard timber. This method of increased security is
-frequently adopted on girder bridges and long iron viaducts which are
-on the straight, and in such cases it is usual to place the guards
-outside each of the rails forming the track.
-
-The introduction of bogie engines and bogie carriages has conduced
-largely to the safe working of the train-service over the curved
-portions of many of our home railways, as well as to the economy in
-the wear and tear of permanent way and rolling-stock. The action of
-long rigid wheel-base vehicles passing round sharp curves is               54
-detrimental to all the parts brought into contact. Not only is there
-the constant tendency to mount the rails, and spread the gauge, but
-the tiny shreds of steel scattered all along close to the
-rail--particles ground off the rails, or off the wheel-tyres, or
-both--testify to useless wear, unnecessary friction, and great waste
-of motive-power.
-
-The gradual increase of accommodation and conveniences in the carriage
-stock of European railways led to the gradual increase in the length
-of the vehicles. The six-wheeled carriage superseded the four-wheeled
-carriage, on account of its increased steadiness when running, but the
-introduction of long sleeping-cars, dining-cars, and corridor cars
-necessitated some better wheel arrangement than the ordinary six-wheel
-type could supply. The six wheels had been spread as far apart as was
-admissible for carrying weight and passing round curves, and something
-had to be done to meet the demand for still longer carriages. Many of
-the six-wheeled carriages at present running on our own home lines
-have a fixed wheel-base as long as 22 feet, and with this length the
-horn-plates must undergo a very considerable strain when adapting
-themselves for the passage round curves of small radius. On a curve of
-15 chains radius (990 feet) a chord of 22 feet will have a versed sine
-or offset of 0·73 of an inch, and on a curve of 10 chains radius (660
-feet) an offset of 1·10 of an inch. Fortunately, curves of the above
-small radius are not very numerous on our main lines; but wherever
-they do occur, the conflict between the long fixed wheel-base
-rolling-stock and the permanent way must be very severe to both.
-Several descriptions of eight-wheeled carriages have been tried on our
-home lines; but the system which is now most in favour is the ordinary
-bogie truck, which has been in use for so many years on all American
-railways. A bogie truck is really a short carriage frame complete in
-itself, with its wheels, springs, and brake appliances, and is
-attached to the under side of the carriage body by a central pivot,
-round which the truck can swivel or rotate sufficiently to adapt
-itself to the curved portions of the line. With a bogie truck at each
-end of a long carriage, the vehicle will pass as easily round curves
-as on the straight line, side pressure, or grinding against the rails,
-is obviated, and friction is reduced to a minimum. The bogie truck may
-consist of four wheels or six wheels, according to the length and
-weight of the carriage to be supported.
-
-[Illustration: Fig. 39, 40, 41, 42]
-
-Figs. 39, 40, and 41 show sketch elevation, plan, and transverse           56
-section of one pattern of four-wheel bogie truck largely adopted in
-American carriage stock, and although there are other types varying in
-detail, the general principle remains the same in all. The diagram
-sketch (Fig. 42) represents the two bogie trucks slightly swivelled to
-adapt themselves to the curve round which the carriage is supposed to
-be passing.
-
-For carriage or waggon stock with an independent bogie truck at each
-end, the central pivot and swivelling motion supply all the freedom
-that is requisite; but for locomotives it is necessary to provide for
-lateral as well as for swivelling movement. The driving and trailing
-wheels--and sometimes one or two other pairs of wheels--work rigidly
-in the frames, and as the normal position of the centre of the bogie
-truck must be in the centre line of the engine for the straight line,
-it is evident that some appliance must be introduced to allow the
-truck to move laterally when the engine has to traverse the curves.
-
-Figs. 43, 44, and 45 give sketch elevation, plan, and transverse
-section of a swing-link bogie truck as applied to an ordinary American
-locomotive. Its recommendations are its simplicity, its efficiency,
-and its accessibility for inspection and lubrication. The swing-links,
-which provide for the lateral movement, are direct acting, and do not
-require any side springs of steel or indiarubber. All the principal
-parts of the bogie are visible and not mysteriously cased in with
-plate-iron boxwork.
-
-In the sketches several minor details are purposely omitted and only
-sufficient particulars shown to explain the method of working. The
-under side of the upper centre plate which carries the cylinder
-castings and smoke-box end of boiler is cup-shaped, and fits into an
-annular groove or channel in the lower centre plate, which is
-suspended from the framework of the truck by the four swinging links.
-Practically the entire carrying and swivelling work of the bogie truck
-is effected by the annular-groove casting moving round the cup-shaped
-casting, and the centre pin is merely passed down through each to
-guard against the risk of the one lifting out of the other from sudden
-shock or derailment.
-
-[Illustration: Fig. 43, 44, 45, 46]
-
-The lateral movement of the truck is obtained by means of the four
-swing-links. When the engine is on the straight road the centre line
-of the bogie is on the centre line of the engine, and the links hang
-in the positions shown on the sketch, inclined towards the centre; but     58
-upon entering a curve they come into play, and allow the truck to move
-out sideways to the right or left, according to the direction of the
-curve, the one pair of links assuming a flatter angle, while the other
-pair approach nearer to the vertical, the extent of side movement
-depending on the amount of the curvature. When the engine enters the
-straight line again, the bogie truck resumes its central position.
-
-The Bissell truck consists of one pair of wheels connected to a
-triangular framework, as shown in Fig. 46. The axle-boxes are attached
-to the side of the triangle which lies parallel to the axle, the other
-two sides terminate in a circular ring which works round a centre pin
-fixed to the engine. These two sides are practically the radii of a
-given circle, and permit a large amount of lateral movement, which can
-be controlled by placing suitable stop-pieces to limit the side play
-to the extent desired.
-
-Radial axle-boxes have been tried on the engines of some railways. In
-the best types the opposite boxes are braced together by a diaphragm,
-or plate-iron framework, to ensure that both boxes work together. The
-curved faces of the horn-blocks, in which the radial axle-boxes slide,
-are struck from a centre taken at some point to the rear of the normal
-centre line of the axle, and stops are placed at proper distances to
-control the extent of lateral movement. Although the advocates of
-radial axle-boxes may urge some points in their favour, there are few
-engineers, if any, amongst those who have had practical experience of
-both systems, who would for a moment claim for the radial axle-box
-anything but a modicum of the many advantages obtained by the
-four-wheeled bogie truck.
-
-As one of the principal functions of a four-wheeled bogie truck for an
-engine is to act as a path-finder, or guide, to the other wheels which
-constitute the fixed or rigid wheel-base portion of the machine, it
-follows, therefore, that the full benefit of the bogie truck can only
-be obtained when it is placed at the leading, or front, end of the
-engine. In this position the bogie, with its swivelling arrangement
-and smaller weights, is the first to pass over the rails, and in doing
-so shapes the course and prepares the way for the easy running of the
-heavier wheel weights which have to follow. When the bogie truck is
-placed at the rear end of the engine, its action is restricted to
-affording lateral movement only, and the driving and coupled wheels
-have to force or pound themselves round the curves in a jerky,
-irregular manner, as compared to their smooth running when following       59
-the leading or guiding influence of a bogie truck in front.
-
-The wheel-base of a four-wheeled bogie truck for an engine should
-always be greater than the gauge of the line over which the bogie has
-to travel On the 4 feet 8½ inch gauge some of the best results have
-been obtained with bogies having wheel-bases varying from 6 feet to 7
-feet. Where the wheel-centres have been less than 6 feet, the running
-has been found to be much less steady than with the wider spacing; and
-where the wheel-base is not more than the gauge, there is a tendency
-for the bogie to catch, or lock, when passing round sharp curves.
-
-
-
-
-  CHAPTER II.                                                              60
-
-  Works of construction: Earthworks, Culverts, Bridges, Foundations,
-    Screw piles, Cylinders, Caissons, Retaining walls, and Tunnels.
-
-
-Earthworks.--Under this heading may be classified cuttings and
-embankments of earth, clay, gravel, and rock.
-
-When setting out a line and adjusting the gradients, an endeavour is
-usually made to so balance the earthworks that the amount obtained
-from the cuttings may be sufficient to form the embankments. With
-care, this may be effected to a considerable extent; but there will be
-places where the material from cutting is unavoidably in excess, and
-others where the cuttings are too small, or contain good rock, or
-gravel, which can be more advantageously used for building and
-ballasting purposes than for ordinary embankment filling. Or there may
-be a large cutting which will provide enough material to form three or
-four of the adjoining embankments; but the distance, or _lead_, as it
-is termed, to the far embankment may be so long, and, perhaps, on a
-rising gradient, that it would be cheaper to run the surplus cutting
-to _spoil_, and _borrow_ other material for the far embankment from
-side cutting or elsewhere. A long lead adds materially to the cost and
-time of forming an embankment, as it not only necessitates a
-considerable length of _service_, or temporary permanent way, but also
-occupies much time in the haulage of the earth waggons. For distances
-of half a mile and upwards, a small locomotive is more suitable than
-horses for conveying the waggons.
-
-To run to _spoil_ is the term applied to such of the material from a
-cutting which, not being required or utilized in the formation of the
-line embankments, is removed and tipped into mounds, or
-_spoil-banks_, in some one or more convenient sites near the mouth of
-the cutting. Sometimes the surplus material is disposed of by
-increasing the width of the embankments. Material excavated in a           61
-tunnel, and hoisted through the shafts to the upper surface, has to be
-deposited in spoil-banks along the centre line of the tunnel.
-
-To _borrow_ material to form an embankment is the term used when the
-earthwork filling is not obtained from the cuttings
-on the line. This borrowing is generally done by excavating
-a trench on each side of the line, of such width and depth as
-will supply sufficient material to form the embankment. Fig.
-47 gives an example of an embankment thus made from side
-cutting. In some cases a piece of high ground adjacent to the
-embankment can be utilized for obtaining a portion, or even
-the whole of the filling.
-
-Increased material is sometimes obtained by widening the
-cutting, or flattening the slopes, or both.
-
-The degree of slope of a railway cutting must be regulated by the
-nature of the material excavated. A slope of 1½ to 1, which gives for
-every foot of vertical height a width of one foot 6 inches of
-horizontal base, as in Fig. 48, is usually adopted for cuttings in
-ordinary earth, good clay, sand, or gravel. There are some
-descriptions of strong clay and marl which will stand at a steeper
-slope, even at 1 to 1; but, on the other hand, there are some kinds of
-clay which must ultimately be taken out to 2 to 1, and even 3 to 1.
-
-It frequently occurs that the slopes of a clay cutting, taken out to
-1½ to 1, appear to stand well for a time, but after exposure to the
-frost and rain of one or two seasons, the material becomes loosened,
-and forms into slipping masses, which slide down on to the line,
-stopping all traffic, and have to be cleared away before train
-operations can be resumed.
-
-Cuttings through solid rock may be taken out to a slope of ¼ to 1, as
-shown in Fig. 49, provided the material is compact, and there is not
-too great a dip in the strata or rock-beds. Where the rock-beds lie at
-a considerable angle, the slope on the high side will have to be made
-flatter than the slope required on the low side, as shown in Fig. 50,
-and great care must be taken to remove from the high side all loose or
-disconnected pieces of rock which might come away and slide down on to
-the line.
-
-[Illustration: Fig. 47, 48, 49, 50, 51]
-
-Strong dry chalk will generally stand at a slope of ⅓, or ½ to 1, but
-when wet and mixed with flints it will be necessary to increase the
-slope to not less than ¾ to 1. Where the rock is loose and
-disintegrated, a slope of not less than ½ or ¾ to 1 will be required,      63
-and at many points there will be detached threatening masses of rotten
-rock which must be cleared away to a much flatter slope for safety. In
-cuttings of this description it is frequently found necessary to clear
-out a portion of the loose pieces of the lower cavities and build in
-their place a facework of masonry to support the superincumbent rock.
-Springs of water rising in the rock, or running over any part of the
-rock slopes, must be properly provided for, and conducted to the
-nearest channel. They should be carefully watched during the winter
-season, when the frost, acting on the water penetrating the crevices,
-splits and separates large pieces which were previously firm and
-secure.
-
-Instances will occur where a cutting has to be made through a thick
-bed of rock and several feet of soft loose strata underneath. The
-effect of forming a cutting through the soft strata is to induce the
-heavy bed of rock above to squeeze or force out the softer material
-below, and unless proper means were taken to avert such a disturbance,
-the entire cutting would have to be excavated to a very flat slope.
-The method adopted in such a case is to build strong face-walls of
-masonry, brickwork, or concrete, underneath the rock, as shown in Fig.
-51, with strong inverts placed at short distances. Suitable
-arrangements must be made to take away the drainage water which will
-collect at the back of the walls, and weeping-holes or outlets must be
-left in the lower part of the walls to convey the water into the
-water-tables on the line.
-
-Where there is a depth of earth cutting on the top of the rock, the
-earth should be cut away so as to leave a bench or space of 3 or 4
-feet between the edge of the rock cutting and the foot of the earth
-slopes, as shown on Fig. 52.
-
-In cases of shelving rock, with earth or clay on the top, as shown in
-Fig. 53, it is frequently found necessary to remove the whole of the
-clay on the high side to prevent the possibility of its sliding off
-the rock on to the line below.
-
-[Illustration: Fig. 52, 53, 54, 55, 56]
-
-In large cuttings it is usual to push forward a gullet of sufficient
-width for one or two lines of waggons, as shown in Fig. 54. When this
-has advanced some distance, strong planks or half balks of timber are
-placed across the gullet, and the sides or wings of the cutting can be
-excavated, the material wheeled to the gullet, and tipped from the
-barrows into the waggons beneath. By this arrangement the work can be
-carried on very expeditiously, as one set of men can be engaged            65
-advancing the gullet and laying the track, while others are following
-up and taking down the sides. A large number of waggons can thus be
-filled in a day, and a small locomotive kept fully employed.
-
-Occasions will arise where the material from a large cutting, situate
-on a continuous gradient, as in Fig. 55, has to be carried in both
-directions to embankment.
-
-In wet weather, or if the cutting is at all wet, it would be almost,
-if not quite, impossible to carry on the excavation at the upper end
-to the proper formation level. The water would collect at the lower
-level, and not having any means of escape, except by pumping, would
-stop the work. In such a case the best way is to take out the cutting
-at the upper end to a slight rising gradient, as shown in the sketch,
-sufficient to carry away all water, and afterwards take out the lower
-portion in the working from the other end of the cutting.
-
-Cases will arise where it will be necessary to make a shallow cutting
-through boggy peaty ground. If the boggy material be very soft, and
-its thickness from the formation level to the solid ground below be
-not great, it may be advisable to remove this extra thickness down to
-the hard lower bed, and fill in up to formation level with strong
-material. If, however, the bog or peat be too thick to justify its
-entire removal, it should be excavated say down to two feet below
-formation level, and a thick layer of branches of trees and strong
-brushwood closely laid and packed the full width of the road-bed. On
-this preparatory foundation must be placed good clean ballast to carry
-the permanent way. Two or three extra sleepers should be allowed to
-the rail length, and in some instances it will be necessary to
-introduce two, or even four, rows of strong longitudinal timbers--half
-balks--under the transverse sleepers. The object of all this extra
-timber is to obtain a large increase of bearing area on the soft
-yielding surface of the boggy material. Notwithstanding these special
-precautions, the trackway will sink down a little during the passage
-of an engine or train, but will generally return to its former level.
-Good side drains or water-tables should be formed at each side of the
-cutting to take away all rain and surface water.
-
-In all cuttings it is desirable to have the line of formation on a
-slight gradient, sufficient to carry away all rain water or spring
-water which may be collected in the water-tables; but more                 66
-particularly so is this necessary in a rock cutting, where the
-material, being non-absorbent as compared with earth or gravel,
-requires that all drainage must be carried away to the mouth of the
-cutting.
-
-In carrying out railway embankments and road approaches, it is usual
-to form the sides to a slope of 1½ to 1, as shown on Fig. 56.
-Occasionally the cuttings produce material which might stand at a
-rather steeper slope, but considering the effects which might
-afterwards be produced by heavy rains falling on the sides, it is more
-prudent to adopt the flatter slope of 1½ to 1. Some descriptions of
-clay will not stand at the above slope, but require a slope of 2 to 1,
-or even 3 to 1.
-
-When proceeding with the earthworks, it is customary to first remove
-and lay aside a layer, say 9 inches in depth, of soil and earth from
-the seat of the embankments and top widths of the cuttings, to be used
-afterwards in soiling the trimmed and finished slopes of the cuttings
-and embankments. This soil being removed, the actual work of the
-excavation can be commenced. The working longitudinal section will
-give all the necessary particulars as to position of the mouths of the
-cuttings and the depths at the various chain-pegs, and the top widths
-of the cuttings can be ascertained by calculation, if on even ground,
-or from the cross-sections if on side-lying ground, according as the
-material may be earth, clay, or rock.
-
-For facility of carrying on the works, reliable bench marks, or
-reduced level stations, must be established at convenient distances
-along the route of the line, and from these and the fixed chain-pegs
-the correct line of formation level can be checked from time to time
-as the work proceeds.
-
-For ordinary earth or clay cuttings, the usual tools are picks and
-iron crow-bars for loosening, or _getting_ the material, and
-shovels for filling into barrows, carts, or waggons. For heavy
-earthworks, steam excavators are now largely employed. Great
-improvements have been made in this class of machinery, in the way of
-perfecting the method of excavating lifting, and filling the material
-into the earth-waggons.
-
-In nearly all rock cuttings the greater portion of the material has to
-be taken out, or loosened, by blasting with gunpowder, dynamite, or
-other explosive. The number and extent of the charges will depend upon
-the nature of the rock and its stratification, and also on its position    67
-as regards proximity to buildings or residential property.
-
-Where the rock is loose, or disintegrated, the pieces can generally be
-readily separated by picks and bars without having to resort to any
-great extent of blasting.
-
-[Illustration: Fig. 57, 58, 59, 60, 61, 62, 63, 64, 65, 66]
-
-The first of the material excavated in the cuttings is generally
-conveyed in wheelbarrows to form the commencement of the adjoining
-embankments. When the wheeling distance becomes too far for economical
-barrow work, ordinary carts or three-wheeled carts, sometimes termed
-_dobbin carts_, are brought into operation where the cuttings and
-embankments are light; but where the earthwork is heavy, both in
-excavation and filling, a service or temporary road of light rails and
-sleepers is usually laid down to carry strong _tip_ earth-waggons. For
-moderate distances these waggons are hauled by horses, but for
-distances over three-eighths of a mile a small locomotive is more
-speedy and economical. Fig. 57 shows one form of dobbin cart; the
-wheels are made with good broad tyres, so as not to sink too deep into
-the soft ground, and the body being attached to the framework by a
-pivot or trunnion on each side, can be readily tilted over, and the
-earth tipped out, by releasing the holding-down catch. Where the
-ground is soft and wet, or of a very loose sandy nature, the work of
-hauling these dobbin carts is very heavy on the horses, and in such
-cases it soon becomes an advantage to lay down a service road of rails
-and sleepers. This service road is formed of light rails manufactured
-for the purpose, or old, worn rails no longer fit for main-line work,
-spiked down on to rough transverse wooden sleepers. The end of the
-embankment in course of formation, and where the earth is being
-tipped, is termed the _tip head_. Two or more roads are required at
-the tip head to form the embankment to its full width. Fig. 58 gives a
-sketch plan of a service road near the tip head. The width is shown as
-for a double line. The earth-waggons are hauled along the line from
-the excavation, and brought to a stand at the point A. If a
-locomotive has drawn the waggons, it is then detached, moved forward,
-and shunted back into the siding BC. A horse accustomed to tipping
-then takes one full waggon at a time over one or other of the two
-turn-outs, DEF or DGH, to the tip head, sufficient impetus being
-given to the waggon to run the front wheels off the ends of rails on
-to cross-sleepers laid close, with a steep rise, and backed up with        69
-earth. This suddenly checks the frame of the waggon, and the body
-containing the excavated material revolves on its trunnion, tilts up,
-and shoots out the material well forward, so that the man in charge of
-the tip head, who also knocks up the “tail-board catch,” is able to
-level off the filling without assistance. The empty waggon is then
-hauled back, and turned into the siding BC, and another full waggon
-taken forward and tipped, until all the waggons of the rake are
-emptied. Ten waggons generally form a rake when the work is pushed
-forward vigorously, each waggon holding about three tons. The tip head
-horse pulls the waggon by a trace-chain having a spring catch at the
-end, by which the driver releases the horse at the right moment. It is
-very important that this spring catch should be kept in good order,
-because occasionally too much impetus is given to a waggon, which,
-running over the tip head down the slope, would drag the horse with it
-if the spring catch did not act properly. Good firm foothold must be
-provided for the tipping horse.
-
-The tip head should never be carried across culverts or bridges until
-they have been well backed up, and protected by a thick covering of
-earth or clay, wheeled in with barrows to an equal height on each side
-of the masonry, so as to prevent undue side pressure.
-
-Fig. 59 gives a sketch of one form of end-tipping waggon. In some
-cases the wheels are made of cast-iron, but as these are readily
-broken during the rough handling to which earth waggons are exposed,
-it is questionable whether the light wrought-iron wheels, with light
-steel tyres, used on some works, are not more economical in the long
-run. The framework and body are made of strong undressed timber, well
-bound and bolted together. The tail-board catch keeps the body of the
-waggon in its proper horizontal position while loading or running, but
-when released leaves the body free to tilt up, and to revolve on the
-front trunnion by means of the circular clip A. The same principle
-is also applied to side-tipping waggons which are used for the
-widening of embankments, or formation of platforms and loading-banks.
-
-The permanent way of these service roads is generally made as simple
-as possible. A pair of movable rails are used instead of switches, as
-shown in Fig. 60. These rails are linked together by iron tie-rods,
-and pulled or pushed over into position for one or other of the roads      70
-by means of the handle at A. A stout iron pin, or iron
-clamping-plate, serves to retain the rails in position during the
-passing of the waggons. In a similar manner, a short rail working on a
-pin, or pivot, is made to answer the purpose of an ordinary crossing.
-The rails are laid complete and continuous for the one road, and for
-the second road the outer rail is laid sufficiently high to cross over
-the rail of the first road. A piece of rail is then secured by a
-centre pin, or pivot, to the cross-sleeper, as shown on Fig. 61. This
-pivoted rail is pulled over into the position shown by the dotted
-lines, to allow the passage of waggons on the one road, or pulled
-across to the end of rail at B, for waggons to pass on or off the
-other road. In the latter case an iron pin or clamp serves to keep the
-pivoted rail in position. As these service roads are merely laid down
-on the soft loose material brought forward for filling, they require
-constant packing and lifting to prevent them working into depressions,
-which might cause the waggons to leave the rails.
-
-To indicate the height of the embankment filling, strong stakes or
-poles must be firmly set in the ground at each chain-peg. On each of
-these poles two cross-bars must be fixed, the lower one placed to the
-correct height of the embankment, and the upper one to show the amount
-allowed for subsidence. The excavated material, as brought from the
-cuttings, is in a soft, loose condition, and an allowance must be made
-for its settlement, or subsidence, as the embankment becomes
-consolidated. This allowance will, of course, depend on the height of
-the embankment and the quality of the material, but for ordinary earth
-and clay it is customary to allow about one inch to the foot of
-height, which is equal to about 8 per cent.
-
-When forming embankments over very side-lying ground, it is necessary
-to cut steps in the sloping surface on which the filling material has
-to be placed, as shown in Fig. 62. These steps give a hold to the new
-earthwork, and check the tendency to slide down the hillside.
-
-Embankments have frequently to be carried over ground which is low,
-soft, and wet, but not boggy. If the culverts and drains are
-sufficiently large, and properly arranged, these places are not likely
-to cause much future trouble.
-
-For a thoroughly soft deep bog, however, it is most difficult to make
-any accurate calculation as to the amount of embankment filling which      71
-will be necessary to form a permanent foundation for the line; and the
-construction of a high heavy embankment across such a place is one of
-those undertakings which every engineer is most anxious to avoid. A
-large quantity of material may be tipped into the bog, and seem to
-stand fairly well for a time, and then suddenly disappear altogether.
-More material has to be brought forward, and will most likely
-disappear in a similar manner. The filling material being heavier than
-the bog on to which it is thrown, falls through, and displacing the
-soft semi-liquid matter, continues to sink down lower and lower until
-it is stopped by a harder stratum underneath. In a measure the
-operation somewhat resembles the tipping of earth into a lake; the
-material will go down until it meets with a solid bottom, and in going
-down it assumes its own natural slope, and forms for itself a width of
-base corresponding to its height. It will be readily understood what
-an enormous amount of filling material will be swallowed up in
-following out such a process. On a very soft bog, say 20 feet in
-depth, over which an embankment 20 feet high has to be formed, the
-extent of the actual earthwork filling will very probably closely
-approach the outline shown in Fig. 63. The upper portion, ABCD,
-representing the embankment proper, will contain about 133 cube yards
-to the yard forward, whereas the lower portion, CDEF, which has
-displaced the soft boggy matter, will contain about 266 cube yards to
-the yard forward, or, in other words, the filling which is out of
-sight will be double the filling which is in view above the section
-ground line.
-
-Apart from the large amount of filling consumed in forming this
-semi-artificial island, the progress of the work itself is very
-perplexing. A long length of the bank may have been raised again, once
-or twice, to the proper height, and may have carried rails and
-earth-waggons for some weeks, and then sink all at once several feet.
-The sinking, too, may not be uniform, but may produce fissures,
-depressions, and separation of the earthwork which will necessitate
-much care when bringing forward fresh filling material. The bog may
-not be of the same consistency throughout, there may be some layers of
-harder material, such as imbedded trunks of trees, and these may
-sustain the filling for a time, and then yield under the increasing
-weight of the superincumbent mass. Even when the embankment is
-finished throughout, and shows no sign of sinking, it should be very
-carefully watched for a long time for any indication of further            72
-movement.
-
-When the bulk of the material has been taken out of an earth or clay
-cutting, the work of trimming the slopes should be put in hand, so
-that any surplus left on the wings, or sides, may be removed, and
-carried away before stopping the earth-waggons. The angle of slope
-having been decided, a battering rule of light wooden boards is made
-to correspond to the slope, and in form similar to that shown in Fig.
-64. A plumb-bob is suspended from a fixed point, A; the lower end,
-B, is then held against a peg or mark which indicates the correct
-level and width of the cutting at the place, and the upper end, C,
-is raised or lowered until the plumb-bob string coincides with the
-vertical line marked on the rule from A to D, and the plumb-bob
-rests steadily in the space cut for it at D. With this battering
-rule a length of seven or eight feet, according to the size of the
-rule, is first trimmed to the correct slope, and by continuing the
-application of the rule up the side, a correct slope line is obtained
-from bottom to top of slope at that place. By repeating the process at
-convenient distances along the cutting, a series of correct slope
-lines are obtained, and the intermediate space can readily be trimmed
-to correspond.
-
-The same form of battering rule and method of working is applicable
-for trimming the slopes of the embankments.
-
-When the slopes of the cuttings and embankments have been trimmed,
-vegetable soil, which has been laid aside, or reserved as previously
-described, should then be spread evenly over the slopes to the uniform
-thickness of not less than four inches, and the whole sown with good
-grass seeds to form a strong sward.
-
-The trimming, soiling, and sowing of the slopes not only gives a more
-finished appearance to the earthworks, but the strong grass, when once
-well grown, binds the surface together, and helps to resist the
-injurious effects of heavy rains and melting snow.
-
-There are many places abroad where a neat finish to the earthworks is
-considered quite a secondary matter, or where it would be difficult to
-obtain suitable soil to spread on the slopes. The earthworks are
-hurried forward to allow the iron highway to be laid down as quickly
-as possible, the slopes of the cuttings and embankments are only
-roughly trimmed, and nature is left to supply such grass or vegetation     73
-as may spring up, or be self-sown.
-
-The fencing in of a line of railway serves the double purpose of
-defining the boundary of the company’s property, and of forming a
-barrier for the prevention of trespass of persons and animals on to
-the line. For our home lines, fencing is compulsory, and the same
-obligation exists on many foreign railways. In our colonies, and out
-in the far West of the United States, and in newly opened out
-countries, fencing, except near towns and villages, is rather the
-exception than the rule; people and animals roam at will from one side
-of the railway to the other wherever they find a convenient crossing
-place, and the cowcatcher of the engine has to be depended upon for
-throwing aside any animal which may be standing, or resting, on the
-line of rails at the passing of a train.
-
-The description of fence will be influenced by the locality, and the
-materials conveniently obtainable. Where stone is plentiful, perhaps
-brought forward out of the cuttings, and labour cheap, a masonry wall
-will be found a most suitable permanent fence. Any fence to be of
-service should not be less than four feet high. A wooden post and rail
-fence is much in favour in some districts, the posts being firmly set
-or driven into the ground, and four or five stout bars nailed on to,
-or set into, the upright posts. This fencing does not last very long,
-the pieces are small in size, and soon fail from decay. Quick or
-hawthorn hedges, when fully grown, make a good fence, but require
-careful attention to prevent gaps being made by roving cattle. They
-also require constant trimming and cutting. The quicks are generally
-planted in a mound formed by cutting a continuous ditch, or gripe, as
-shown in Fig. 65. The ditch serves as a drain to take away water
-running down the slopes of the embankments, small openings in the
-mounds, or drain pipes through them, forming leaders to conduct the
-water to the ditch or gripe. The outer edge of the ditch represents
-the boundary of the railway property, unless specially arranged
-otherwise.
-
-Galvanized iron-steel wire fencing, if not made too light, is strong
-and durable, and very easily kept in order.
-
-The wires may be secured to strong wooden posts, which should be
-creosoted, and not placed too far apart, or to iron posts or standards
-of angle iron or tee-iron section. The straining-posts, whether of iron    74
-or timber, must be stronger than the intermediate posts, firmly fixed
-into the ground, and well stayed, to withstand the pulling and
-tightening of the wires. There are many places where a quick fence
-would not grow, and where the ground is too soft to carry a wall. In
-such cases a good galvanized-wire fencing will fulfil all
-requirements. The strand wire is better than the plain wire, as its
-method of manufacture necessitates the use of a superior material, and
-it is easier to straighten and keep in good order. An extra strong
-fence is often made of six, eight, or more rows of round rod-iron
-secured to wrought-iron uprights of bar-iron or tee-iron.
-
-In hot countries abroad an excellent fence is obtained by planting a
-species of cactus or aloe in a similar manner to the quick fences at
-home, and as shown in Fig. 66. These cactus plants are readily
-obtained, are very hardy and quick in growth, and with their large
-spike-shaped leaves form such an almost impenetrable barrier that few
-animals will attempt to pass.
-
-Road approaches to bridges over or under the line, or to public road
-level crossings, may be fenced in the same manner as the line proper.
-If quicks are adopted, it will be necessary to put up a light wooden
-fence also to protect the young plants until they are well grown. Near
-towns and villages it is frequently found advisable to adopt a
-specially strong wooden fence, or close-boarded fence, where the
-approach is an embankment, and too newly made to carry a wall.
-
-Gates for farm or occupation level crossings may be made of wood or
-iron. As a rule, iron gates are preferred, as they can be supplied at
-the same cost as wood, and are very much more durable. Gates for
-public road level crossings have to be so placed that they will either
-close across the railway or across the road; their length will
-therefore depend upon the width and angle of the road crossing. It is
-better to make these gates of wood, so that, in the event of a train
-running through them, there may be less risk of injury to life and
-rolling-stock than if they were made of iron. For footpath crossings,
-small gates, wickets, or stiles may be adopted of such form as may be
-found most suitable for the requirements.
-
-
-Culverts and Drains.--Before proceeding with the formation of the
-embankments, it is necessary to construct the culverts and drains
-which will be covered over by the earthworks. Any existing drains
-which may be of too light a description must be reconstructed in a         75
-more substantial manner. It is a simple and comparatively inexpensive
-matter to rebuild a drain before the earth filling is brought forward,
-but it is a costly work to open out an embankment, and rebuild a
-culvert afterwards. Unless the seat of an embankment is well drained
-and kept free from the accumulation of running water, the earthwork
-will be exposed to washing away of the lower layers, and consequent
-subsidence. Each watercourse or open drain must be provided for either
-by a separate culvert of suitable size or, as may be done in some
-cases, by leading two or more watercourses into one, and thus passing
-all through one culvert of ample capacity. When fixing the sizes of
-the culverts they must not be limited to the normal flow of water, but
-a large margin must be allowed sufficient to meet extraordinary
-floods. The depth of the bed or invert of a culvert is a very
-important point. If laid too high, and the stream above should at any
-time deepen, the high invert would check the flow of the water, and
-would also incur the risk of being undermined and gradually carried
-away. If, on the other hand, the invert be laid too low, it will
-gradually silt up to the level of the stream-bed alongside, and there
-will be so much of the culvert space lost for all practical purposes.
-In cases when the invert of a culvert has to be laid at a special low
-depth to allow for future improvements in drainage, it is advisable to
-give extra height from the invert to the crown, or top, so as to
-provide ample waterway in the event of any silting up in the mean
-time. Particular care should be taken when building the foundation of
-a culvert. It has to be laid on the site of the watercourse, or on a
-new channel which will ultimately form the watercourse, and it should
-be built sufficiently deep into the ground to avert as far as possible
-the chance of water finding a course through below the foundation.
-
-The invert may be of stone pitching or brick if the current is not
-rapid, or liable to bring down stone boulders from its gravelly bed.
-
-With a stream-course having considerable fall, and which carries with
-it large stones, roots of trees, and other _débris_, the invert should
-consist of strong pitching, composed of large-sized, rough-dressed
-stones of hard, durable quality, capable of withstanding the pounding
-of the boulders brought down during floods. A soft description of
-stone would be quite unsuitable for the invert of such a stream; the
-pitching would wear away quickly, break, and become detached, leaving      76
-the foundation and side walls exposed to the cutting inroads of the
-water.
-
-Where large flat bedded stones or flags of tough quality can be
-obtained, they form good covers, or tops, for culverts up to two feet
-in width. They should have not less than nine inches bearing on the
-side walls, and their contact edges should be fairly dressed, so as to
-fit sufficiently close to prevent the embankment filling from falling
-through.
-
-Where the stream, or run of water, is very small, strong earthenware
-pipes, 9 inches or 12 inches in diameter, well bedded, may be
-sufficient to carry away all the water likely to arise. For small
-springs in low swampy ground, dry stone drains may in many cases be
-used with advantage. These are made by cutting a trench, say two feet
-deep by twelve or eighteen inches wide, in the seat of the embankment
-from side to side, and filling it up with dry rubble stones, not
-boulders, hand-laid, the upper layer placed on the flat to keep the
-earthwork as much as possible from filling in between the stones.
-
-In soft boggy ground, where the depth to a hard bottom is very
-considerable, wooden culverts are frequently adopted. Although these
-cannot be classed as permanent structures, still, when they are made
-of sound well-creosoted timber, and substantially put together, they
-last for a number of years. Sometimes they are made cylindrical in
-section--a species of elongated cask with strong iron hoops every few
-feet. Others are rectangular in section, made with two strongly
-trussed side frames connected and covered with cross-planking and
-longitudinal tie-planking on the top and bottom.
-
-Wooden culverts are seldom made of very large size, rarely exceeding
-an opening of 3 feet, and it is considered preferable to use two of
-these culverts of moderate dimensions than one of large size. Figs. 67
-and 68 give sketches of wooden culverts of cylindrical and rectangular
-section, and Fig. 69 of flag top culverts of 12-inch, 18-inch, and
-2-foot openings. In masonry culverts the side walls are shown to be of
-rubble stonework, but brickwork can be used instead, provided the
-bricks are well burnt, hard, and capable of withstanding the action of
-the water.
-
-[Illustration: Fig. 67, 68, 69, 70, 71]
-
-In Figs. 70 and 71 are shown types of arch-top culverts of 4 feet and
-6 feet span respectively. The arch portion is shown to be of brick,
-which, as a rule, is cheaper than stone rings, which must be cut and       78
-dressed to suit the small radius of the arch. The side walls may be of
-brick of good quality. Occasionally they are built of concrete. The
-wing walls may either be carried out in the direction of the stream,
-as in the sketch of the 6-foot culvert, or they may be built
-transverse, as shown on the 4-foot culvert, whichever arrangement is
-found to work in the best for the case in question.
-
-For arch culverts on very steep side-lying ground it is better to
-build the arch-top in steps, as shown in Fig. 72, instead of forming
-it parallel to the invert, or slope, of the stream-course. The level
-portions of the arching give a better hold for the embankment than
-could be obtained on a long inclined surface of brickwork or masonry.
-
-The writer has built a large number of culverts of this type for
-mountain streams on steep hillsides, and has found them to prove
-satisfactory in every way.
-
-In embankments alongside tidal rivers, or across the corners of
-estuaries of the sea, culverts have frequently to be so constructed
-that they will permit the passage of the drainage water from the land,
-or high side, without admitting the tidal water. This can be arranged
-by placing at the lower end of the culvert close-fitting hinged-flap
-valves opening outwards. When the tide has gone down the weight of the
-fresh, or land, water swings the flap-valve sufficiently open to allow
-of a free passage; and, on the other hand, when the tide rises, the
-pressure of the water against the face of the flap-valve keeps it
-tightly closed, and prevents ingress of the salt water.
-
-Culverts are sometimes fitted with lifting-valves or doors, which can
-be raised or lowered to serve irrigation purposes. The door, which
-works in guides, is made sufficiently heavy to fall with its own
-weight, and the raising is effected by means of a screwed
-suspension-rod working in a well-secured fixed nut.
-
-In cases of soft or treacherous ground, timber-piling or wide
-bed-courses of cement concrete are necessary to form firm foundations
-for culverts. Drains and streams which are intersected by a railway
-cutting have to be dealt with according to their size and their height
-above the finished rail level. The water from a small drain or field
-spring may be conducted in pipes down the slope of the cutting into
-the water-table, or side drain, at formation level, and will be thus
-carried away to the lower level at the entrance of the cutting. In
-many cases streams can be diverted, and the water led away to some         79
-lower point without the necessity of actually crossing the railway.
-With a large stream, where it is essential that the water should be
-conveyed across the line and continue on its ordinary course, it may
-be carried over in iron pipes or iron trough if there is ample
-headway, or in iron syphon pipes where the height is not sufficient.
-The iron pipes or trough can be supported on masonry or brick piers,
-or cast-iron columns, the height from the rails to the underside of
-the conduit being not less than that adopted for the over-line
-bridges.
-
-Occasionally the pipes can be carried across on an over-line bridge,
-either by placing them under the roadway or on small brackets outside
-the parapet.
-
-With the syphon arrangement the iron pipes must be laid down the
-slopes of the cutting and under the road-bed of the permanent way. The
-pipes must be continuous, strong, and firmly connected at the joints
-to prevent leakage. The inlet and outlet ends of the pipes should be
-securely built into receiving-tanks of masonry, brickwork, or
-concrete, to ensure an uninterrupted flow of the stream, and also to
-prevent any of the water from percolating through under the pipes and
-on to the railway. As a precautionary measure, it is well to place
-iron gratings some little distance in advance of the syphon pipes to
-intercept and collect any brushwood, straw, or other things which
-might be brought down with the stream.
-
-Fig. 73 gives an example of the syphon arrangement as constructed with
-two cast-iron pipes placed side by side.
-
-Railway works carried out in cities and large towns, whether they take
-the form of cuttings, embankments, arching, or tunnels, are certain to
-cause a very considerable disturbance of existing drains, corporation
-sewers, gas-pipes, water-mains and underground telegraph wires. Some
-of these underground works may be so peculiar and complicated as to
-necessitate a slight deviation from the course originally intended for
-the line. Suitable provision will have to be made for each of the
-items interfered with by the railway, and the substituted work must be
-carried out to the satisfaction of the constituted authorities within
-the municipal boundaries.
-
-[Illustration: Fig. 72, 73]
-
-
-Bridges.--Amongst the many bridges and viaducts which have to be
-built during the making of a railway those constructed over rivers and
-waterways are generally the most important The bridging across any         81
-navigable river or tidal water can only be effected in compliance with
-conditions imposed by the authorities controlling the navigation
-rights. These conditions will place restrictions as to the number and
-distance apart of the piers, as well as the height from high water
-level to the under side of the arches or girders. For rivers having a
-constant traffic of sea-going vessels of large tonnage and lofty masts
-the authorities will demand great height or headway as well as large
-spans; and if to this be added a deep water-way and bad foundations,
-the work to be constructed becomes one of considerable magnitude. The
-banks of the river must be carefully studied to find the most
-favourable point for crossing, and in some cases it may be prudent to
-make a detour of two or three miles. The crossing at a great height
-involves the construction of the approach lines at a great height
-also. If the river is in a deep valley with high sloping sides the
-natural contour of the ground facilitates the formation of the
-approach lines; but with a river on a low, wide, open plain, inclined
-approach lines add enormously to the cost of construction, as well as
-to the cost of permanent working.
-
-If the number of sailing craft passing up and down the river be
-moderate, and, perhaps, only passing at high water, the authorities
-may permit a low-level viaduct with an opening bridge.
-
-There are thus the two systems: the high-level viaduct, which allows
-trains to pass over and vessels to pass under at any and all times,
-and the low-level viaduct with opening bridge, which, if open for
-vessels, is closed for trains, or _vice versâ_.
-
-Every crossing of a navigable river will have to be considered and
-dealt with according to its own individual requirements. An
-arrangement suitable for the one may not be admissible or prudent for
-the other. A frequent and important train service might be much
-interfered with by an opening bridge, and, in a similar manner, an
-opening bridge might cause much interruption and detention to the
-navigation of the vessels on the river.
-
-[Illustration: Fig. 74, 75, 76, 77]
-
-Where a low-level viaduct with opening bridge can be adopted, there
-will be a very great saving of expenditure; and there are numbers of
-such viaducts in existence, accommodating a large railway and river
-traffic without inconvenience. Even with a low-level viaduct the
-height from water-level to the under side of the girders of the various    83
-fixed-spans will generally be sufficient for the passage of barges and
-small craft, leaving the opening portion to be used by the larger
-vessels.
-
-The principal openings for these large river viaducts are generally
-constructed for girders, partly on account of the greater facility of
-girder work for large spans, and also for the advantage of having one
-uniform height, or headway, from pier to pier.
-
-For a high-level viaduct across a deep-water river, the cost of the
-lofty piers forms a very important part of the undertaking. Each pier
-will require its own cofferdam, caisson, or other appliance for
-obtaining a suitable foundation. The deeper the water, the more costly
-the arrangement for foundation; and the higher the pier to rail-level,
-the greater the amount of material in the construction of the pier.
-The consideration of these two points will at once show that it is
-very desirable not to have more of these costly piers than is actually
-necessary, and in studying out the design it will be a question for
-calculation how far the spans may be increased so as to dispense with
-one or more piers.
-
-In every work of this description there is a relative proportion
-between span and height, which will give the most economical result
-from a cost point of view; the proportion varying according to the
-depth of the water and description of ground for foundations. An
-increase in the span will naturally necessitate an increase in the
-thickness of the pier; but where a cofferdam, or arrangement for
-putting in the foundations, must in any case be made, a small addition
-to its width may not necessarily form a large increase to its cost.
-
-Figs. 74, 75, 76, and 77 are sketches of high-level railway viaducts
-which have been constructed with great height, or headway, to allow
-large vessels to pass under at all times without interruption. This
-description of work is very costly, not only in the deep-water
-foundations, but also in the heavy scaffolding and appliances
-requisite for building piers and girders at such an elevation above
-the ground-level. The hoisting of the material alone forms an
-important item where such vast number of pieces have to be lifted to a
-height of 80, 90, or 100 feet.
-
-[Illustration: Fig. 78, 79]
-
-Figs. 78 and 79 are sketches of low-level viaducts constructed with
-one large opening span, or swing-bridge, for the passage of vessels.
-The girders and roadway of such opening span are usually constructed       85
-as a compact framework, which revolves on a centre placed in the
-middle of a circular roller path or species of turn-table. The
-portions of the rotating opening bridge, although not always the same
-length on each side of the centre-pin, are generally very carefully
-balanced, to preserve the equilibrium of the entire mass when swinging
-round for the passage of vessels. To ensure stability in working, and
-steadiness during heavy gales, a liberal diameter should be given to
-the roller path of all swing-bridges having large span and great
-weight.
-
-Lattice, or truss, girders are preferable to plate girders for
-swing-bridges of considerable opening, as they present less surface
-area to the action of the wind.
-
-The opening and closing of these bridges is effected by wheel-gearing
-actuated by hydraulic, manual, or other motive-power. The revolving
-machinery should be set solid and true, well protected from the
-weather, and, at the same time, readily accessible for constant
-inspection, lubrication, or repair.
-
-Figs. 80 to 85 are sketches of various types of railway bridges
-constructed for smaller openings across narrower rivers, water-ways,
-or canals. Fig. 80 is an example of what is known as a _bascule_
-bridge. This particular bridge is made in two halves, meeting in the
-centre of the span, the tail end of each half being provided with
-heavy counterweights to assist in opening or tilting up the bridge for
-the passage of vessels, or lowering it down for railway traffic. Each
-half of the bridge swings on horizontal axles, and the raising or
-lowering is effected by means of hand winches or other motive-power,
-actuating wheel-gearing working into toothed vertical segments
-attached to the tail end of each half. The same principle has also
-been applied to bridges having only one leaf to tilt up to clear the
-passage way.
-
-Railway bridges of this pattern are now very rarely adopted. They have
-the great drawback that when raised to the vertical position, a very
-large area is presented to the action of the wind, and this defect
-might lead to very serious consequences in the case of a bridge
-situated in an exposed locality. An open-work floor diminishes the
-wind area, but a very large surface must necessarily remain.
-
-[Illustration: Fig. 80, 81, 82, 83, 84, 85]
-
-Fig. 81 illustrates what is known as a _traversing bridge_. In this
-case the width of the opening passage-way and the adjoining span are       87
-made the same, and the girders for the two spans are constructed in
-one continuous length. By means of gearing attached to the fixed
-portion of the work, the continuous length of girder, with its
-roadway, is first slightly raised or lowered, and then drawn back on
-rollers sufficiently far to leave the opening span quite clear for the
-passage of vessels. A reverse movement of the gearing causes the
-movable girders and roadway to travel back and return to their
-original position ready for the train traffic.
-
-Opening bridges are sometimes constructed on this system in cases
-where the level of the rails is only a few feet above the level of the
-water, and where there is only one water opening, and that not more
-than 20 to 30 feet wide. In such bridges the movable portion is rolled
-back along iron rails, or plates secured to masonry walls, or strong
-pile-work. This class of bridge is cumbersome, slow to move, and is
-now but very rarely adopted.
-
-Fig. 82 shows a type of simple _lift_ bridge, of which there are but
-few examples remaining. In this particular bridge the girders and
-roadway form a solid framework, which rests on the abutments during
-the passage of the trains. Strong chains, secured to the corners of
-the framework, pass over large sheaves on the top of the iron
-standards, and then round drums placed below the level of the rails,
-and terminate by attachment to heavy counter-weights suspended in iron
-cylinders. The counter-weights are adjusted to approximately balance
-the bridge, so that a moderate power applied to the wheel-gearing on
-the drums is sufficient to raise the roadway to the required height.
-This class of opening bridge is only suitable for the passage of
-barges and small craft without masts; and it requires the
-re-adjustment of the counter-weights when the roadway varies in
-weight, in consequence of rain or repairs.
-
-Figs. 83, 84, and 85 are sketches of small _swing_-bridges constructed
-for narrow waterways. Although differing in appearance, they are all
-practically on the same principle, with centre pin and roller path,
-and are similar in general arrangement to the large-size-opening
-swing-bridges shown in Figs. 78 and 79.
-
-[Illustration: Fig. 86, 87, 88]
-
-The _swing_-bridge arrangement is so simple in construction,
-convenient for inspection, and easy to maintain, that where possible
-it is now generally adopted in preference to any other system. The         89
-weights on centre pin and roller path may be distributed as considered
-most expedient, and by means of suitable appliances the weight may be
-altogether taken off the centre and rollers when the bridge is closed
-for the passage of trains.
-
-There are many wide rivers which, although not navigable in the
-ordinary acceptance of the term, nevertheless require bridges of large
-spans to provide free waterway for the floating down of rafts of
-timber. Away in the high ground, in the timber-growing districts,
-trees are felled, sawn or cut into long poles, logs, or scantlings,
-and hauled to the banks of the river. The timbers are then formed into
-large rafts of the most convenient form for floating down to the place
-of distribution or port for shipment. Even with old experienced
-floaters, using their long sweeps in the most skilful manner, it is
-difficult to take anything but a very irregular course down the
-stream. Under the most favourable circumstances one of these large
-rafts is an unwieldy, awkward craft to manage; but in a river full of
-twists and turns, with reaches varying from comparative smooth water
-to miniature rapids, the current carries the huge mass surging along,
-and only a clear, unobstructed channel will enable its navigation to
-be carried out with safety. The presence of a pier in the main
-waterway might cause destruction to the rafts and loss of life to the
-men. The vested interests in floating rights are tenaciously guarded,
-and no new bridge would be sanctioned which would in any way interfere
-with the waterway or endanger the passage of rafts down the river.
-Bridges of this description are much less costly than those over deep
-water--navigable rivers. Excepting the large spans, the rest of the
-work is comparatively simple. The water is generally shallow, and much
-reduced in quantity during the summer months. Good foundations can
-generally be obtained without going to any great depth. The headway
-may be kept low, or of such height as may best suit the purposes of
-the railway, and be sufficiently well up out of the way of the floods
-which may take place from time to time on the river.
-
-[Illustration: Fig. 89, 90]
-
-Fig. 86 is a sketch of a bridge constructed over a river much used for
-rafting purposes. The large span is over the main channel, and the
-small spans are over a wide gravelly foreshore, which is only covered
-with water during exceptionally high floods in the autumn or winter.       91
-No rafting can be carried on when the river is in flood; the current
-would be too strong to permit of the raft being kept under control.
-
-Fig. 87 is a sketch of a similar bridge where the river is confined to
-a regular channel between two sloping banks of strong clay.
-
-Fig. 88 shows a bridge erected over a narrow rocky pass in the river.
-The channel is hemmed in by the almost perpendicular sides of mountain
-granite, there are no banks to overflow, the flood waters cannot
-spread laterally, however much they may increase in depth, and with
-building-stone at hand in abundance, and foundations formed in the
-solid rock, the situation is one of the most favourable for a strong
-permanent bridge. The cast-iron arch of 150-feet span has a graceful
-appearance, and harmonizes well with the surrounding scenery. A small
-masonry arch at each end of the bridge provides for communication
-along the banks of the river.
-
-With rivers which are neither under the control of navigation
-authorities nor used for rafts of timber, there is much greater
-freedom for the designing and carrying out of bridges or viaducts
-suitable for the actual physical conditions of the locality. The
-headway will be guided only by the height of the railway to be carried
-across, and by any flood-water levels which may affect the work. The
-size of the spans will be regulated by the width of the river, the
-depth of the water, and the nature of the ground into which the piers
-have to be built. For broad, shallow rivers with good firm river-beds,
-piers may be built at moderate cost, and comparatively small spans
-adopted; on the other hand, with a broad deep river it will be better,
-as previously explained, to reduce the number of piers and increase
-the span. In the one case, for example, a river 150 feet wide may be
-crossed with three spans and two piers in the shallow water, as in
-Fig. 89; in the other it may be more prudent and economical to cross
-in one span, without any intermediate pier, as shown in Fig. 90.
-
-[Illustration: Fig. 91]
-
-Next in importance to the large bridges and viaducts over rivers are
-the viaducts which have to be constructed for the crossing of deep
-inland valleys. The occurrence of one of these deep valleys between
-long lengths of average table-land renders necessary either a series
-of cuttings and falling gradients to get down to a low level, or the
-erection of high-level works to continue onward the rail-level at the      93
-height already attained. A decision to adopt the latter course brings
-forward the consideration as to the method of carrying out the work.
-To form a high embankment across such a valley would entail an
-enormous expenditure for earthwork, and several openings, or bridges,
-would have to be made in the embankment for streams, rivers, and
-roadways. Instead, therefore, of making this part of the line entirely
-of embankment, it is usual to carry the earthwork forward until the
-height is about 25 or 30 feet, and to form the remainder of the
-opening of arching, as shown in Fig. 91.
-
-This arrangement is not only less costly than an embankment of such
-height, but has also the great advantage that any or all of the arches
-are available for the passage of streams, rivers, roads, and
-accommodation works.
-
-The character of the work to be carried out in the construction of
-bridges or viaducts over rivers or valleys must greatly depend upon
-the description of materials at command. Where good building-stone is
-plentiful, and the price of labour moderate, works of masonry should
-be adopted as far as practicable. Brickwork is an excellent substitute
-for masonry, provided that specially selected bricks are used for all
-facework, or parts exposed to the weather. For water-washed piers and
-abutments, the lower portion should be faced with good hard stone.
-
-[Illustration: Fig. 92]
-
-Bridges and viaducts consisting of arches of masonry or brickwork form
-the most substantial and permanent works of construction for railway
-purposes; once properly built, the expenditure on future maintenance
-or repairs is merely nominal. For viaducts the span of the arching
-must be regulated by the height of the viaduct. The greater the height
-the larger the span. In one case 30-feet spans may be suitable,
-whereas in another it may be more economical to introduce spans of 60
-feet or more, and so reduce the number of lofty piers. From a cost
-point of view there is, however, a limit to the span of arching, and,
-except for special cases, where expenditure is of secondary
-importance, large spans are very rarely adopted. Arches of large
-spans, no doubt, have been built both in masonry and brickwork, and
-have been a complete success in every way except expense.
-Unfortunately, the quantity and weight of materials in arching, and
-the corresponding cost, increase very rapidly as the span increases,       95
-and for openings of more than 60 or 70 feet girder-work becomes much
-cheaper than arching.
-
-Figs. 92 and 93 are examples of viaducts having piers of masonry, with
-girders to carry the roadway. In the one case the roadway is carried
-on the bottom flange of the girders, and in the other on the top. The
-latter arrangement affords greater facility for securely bracing the
-girders together, while for the former it is claimed that the girders
-form a massive parapet, which would serve as a protection in the event
-of an engine or vehicles leaving the rails.
-
-In the early days of railways, many large viaducts were constructed
-having masonry piers, and timber trusses to carry the roadway. Much
-ingenuity was displayed in designing the trusses, and in the
-introduction of cast-iron joint-shoes and wrought-iron bracings. Many
-of these wooden superstructures served well for several years, but
-they were always exposed to the imminent risk of destruction from
-fire, and however carefully the logs may have been selected, the decay
-of the timber was only a question of time. The deterioration of one
-piece was equivalent to the weakening of the entire truss, and the
-renewal of any part was both difficult and costly. The shrinkage of
-the timber, and the working at the joints, caused the trusses to
-deflect considerably under a passing load, and although the actual
-strength of the structure may not have been much impaired, the
-creaking and depression had anything but a reassuring effect. Timber
-superstructures for anything but small spans are rarely adopted now,
-except for temporary works, or on lines abroad, where the transport on
-girder-work would be very costly, and where good timber is very cheap
-and abundant. Even in the latter case the wooden superstructure is
-generally looked upon as a temporary expedient, to be replaced at no
-very remote date with iron or steel girders, when the materials can be
-conveyed over the entire completed line.
-
-Figs. 94, 95, and 96 are sketches of three types of timber trusses as
-constructed in viaducts of several spans.
-
-[Illustration: Fig. 93]
-
-There are many localities, especially abroad, where suitable stone is
-most difficult to obtain, and very expensive to work and convey. In
-such cases it is compulsory to use as little of it as possible, and to
-resort to iron or steel both for the girders and a large portion of
-the piers. The piers may be made of cast-iron, wrought-iron, or steel,     97
-of suitable form and arrangement to ensure strength and stability. Not
-only must the piers be strong enough to carry the weight that may be
-brought upon them vertically, but they must have sufficient width of
-base to ensure lateral steadiness. The design should admit of facility
-of erection, with a minimum of scaffolding, and the pieces should be
-of convenient length and weight for transport. The lower length of
-river piers, or portion liable to be in contact with flood-water,
-should be of solid masonry, to resist the action of the water, or of
-any _débris_ brought down by the current. More than one fine
-viaduct has been swept away for want of due attention to the latter
-precaution.
-
-Fig. 97 illustrates a type of pier composed of cast-iron columns, well
-braced and stayed with wrought-iron. The ends of the columns and all
-contact surfaces should be properly turned and faced by machinery to
-ensure true and perfect joints, and the socketed ends should be turned
-and bored to fit closely. The latter is important, and if not
-carefully carried out, a slight sliding movement of the flanges may
-take place, and throw undue strain on the bolts.
-
-Fig. 98 shows a very similar pier, constructed entirely of
-wrought-iron or steel.
-
-Each of the above-described piers has a liberal amount of taper or
-batter, both in the front and transverse elevation.
-
-The size and number of the columns, and the dimensions of the braces
-or stays, will depend upon the height of the pier and the weights and
-strains to be sustained.
-
-Many important and lofty viaducts have been erected on this principle
-of iron piers springing from masonry foundations, more particularly
-across deep rugged ravines abroad, where iron piers offered the only
-practical, substantial means of dealing with what appeared otherwise
-an impossibility.
-
-[Illustration: Fig. 94, 95, 96, 101]
-
-[Illustration: Fig. 97, 98]
-
-[Illustration: Fig. 99]
-
-[Illustration: Fig. 100]
-
-Fig. 99 is a sketch of the Kinsua Viaduct on the Erie Railway, one of
-the highest railway viaducts in the United States. In the transverse
-elevation the piers have a large amount of taper; but in the front
-elevation they are vertical, and of width to correspond to one of the
-small spans of the main girder. This arrangement of long and wide base
-gives great stability to the pier. The spans of the girders, which are
-of the ordinary lattice type, are not large, being 61 feet for the
-clear spans, and 38 feet 6 inches for those over the piers. The
-principal interest is in the great height and simplicity of the piers.    102
-The rail-level over the top of the pier is 301 feet above the level of
-the water in the Kinsua stream. The width of this pier on the top is
-10 feet (for single line), and the width at the bottom 103 feet.
-
-Fig. 100 is a sketch of the Loa Viaduct on the Antofagasta Railway,
-Bolivia, stated to be the highest railway viaduct in the world. The
-arrangement of spans and piers is very similar to the Kinsua Viaduct.
-The main spans are 80 feet, and the pier spans 32 feet. The width of
-the pier on the top is 10 feet 6 inches (for single line), and the
-width at the bottom of the highest pier is 106 feet 8 inches.
-
-In contrasting these light iron piers with what would have been
-required if constructed of masonry, an idea may be formed of the
-enormous amount of material, labour, and time, which would have been
-expended to erect the work in stone.
-
-Before the principle of lofty iron piers had been thoroughly
-developed, many high piers had been built of timber both at home and
-abroad. More particularly was this the case in the United States of
-America, where the presence of magnificent timber close to hand
-offered special inducements for the use of wood. Like a mammoth
-scaffolding, each pier was constructed with a most liberal supply of
-material, judiciously selected and carefully put together, but the
-danger of destruction by fire was ever present from the beginning.
-Probably more timber piers and bridges have been destroyed by fire
-than have been removed on account of natural decay.
-
-One of the most notable of these timber-pier constructions was that of
-the Old Portage Viaduct, on the Erie Railway, U.S.A. Fig. 101 is a
-sketch of one or two of the piers. This viaduct was more than 800 feet
-long, and 234 feet high from the bed of the river to the rail-level.
-The spans were 50 feet each. Masonry piers were carried up to about 25
-feet above the ordinary water-level of the river, and upon these the
-timber superstructure was erected. Each timber pier consisted of three
-complete sets of framework, securely connected together, and also well
-stayed and braced to the adjoining piers. This viaduct was destroyed
-by fire in 1875, and was reconstructed with piers and girders of iron.
-
-Railway bridges over or under public roads of primary or secondary
-importance must be constructed to the widths and heights prescribed
-for such works in the fixed regulations of the country in which they      103
-have to be built. As a rule, these road-bridges are simple and
-inexpensive in character, except in towns, or in cases where the line
-crosses the roads very obliquely, or where the road is situated at the
-top of a deep cutting, or bottom of a high embankment. Away from towns
-and out in the open country, permission is generally obtained to
-divert the roads to a moderate extent, so as to obtain a more
-favourable angle and height for the bridge; but in towns, where the
-roads become streets, sometimes of great width, with houses and shops
-on each side, little or no diversion can be allowed.
-
-A railway passing through a portion of a densely populated town must
-deal with the streets as they exist, as any great alteration in their
-course or continuity would involve a large destruction of property.
-With careful laying out it is possible to obtain favourable crossings
-for many of the streets, but a number of others must be crossed
-obliquely, and these oblique crossings very frequently result in a
-span twice the width, or even more, of what would be necessary to
-cross the street on the square. Bridge-work in towns is more costly
-than in the country, as a higher class of work is demanded, more
-finish or dressed work in the masonry or brickwork, and more
-ornamentation in the screens and parapets in connection with the iron
-girder-work. The work itself has to be carried on in a confined
-locality, with limited space for materials and appliances, and where
-the thoroughfare must be kept open.
-
-Where the height is sufficient, and suitable materials readily
-obtained, it is preferable to adopt an arch bridge, as being of a much
-more permanent character than girders.
-
-Fig. 102 is an example of an ordinary over-line arch bridge to carry a
-public road over a double line of railway in a cutting of moderate
-depth.
-
-Fig. 103 shows a somewhat similar over-line arch bridge, but its
-height from rail to road-level being greater, side arches are
-introduced in preference to long heavy wing walls.
-
-Fig. 104 shows an over-line arch bridge in a rock cutting. In this
-case, by increasing the span and forming the springing bed in the
-solid rock, the masonry of abutments and wing walls may be reduced to
-a minimum.
-
-Fig. 105 is a sketch of an ordinary under-line arch bridge to carry a
-railway over a public road in an embankment of moderate height.
-
-[Illustration: Fig. 102, 128, 129, 130]
-
-[Illustration: Fig. 103]
-
-[Illustration: Fig. 104]
-
-[Illustration: Fig. 105]
-
-[Illustration: Fig. 106]
-
-[Illustration: Fig. 107]
-
-Fig. 106 shows a similar under-line bridge, but with curved instead of    110
-straight wing walls.
-
-Fig. 107 is an example of an under-line arch bridge in a rather high
-embankment, and where side arches have been adopted instead of long
-wing walls.
-
-The above six types are equally applicable for private roads crossing
-the railway, but, as previously mentioned, a lesser width and headway
-will be accepted for under-line bridges for private or occupation
-roads, than for public roads. For the over-line bridges, however, the
-width and headway will be regulated by the number of lines and
-standard height of the railway.
-
-When these arch bridges have to be built on the skew to suit an
-oblique crossing of the road, extra care will be necessary in setting
-out the work, and marking on the centering the spiral courses of the
-arching.
-
-Arch bridges may be built of masonwork or brickwork, or a combination
-of the two. If the available quarries do not yield good flat bedded
-stones readily worked, it is better, where possible, to use strong
-hard bricks for the arching, and utilize the stone for the remainder
-of the work.
-
-Although arching undoubtedly forms the most durable type of
-bridgework, numbers of cases occur where the available height or space
-between rail-level and road-level is too small, or the cost of masonry
-and brickwork too great, to admit of anything but girder-work.
-Detailed sketches of some of the many forms of girder bridges are
-given in Figs. 132 to 153, illustrating various systems of roadways
-and parapets. In some instances the main girders are made sufficiently
-deep to serve as parapets, while in others a shallower girder has been
-adopted, on top of which has been placed a light cast-iron parapet
-composed either of close plate-work or of ornamental open railings.
-The open ironwork parapet has a good appearance, but as a screen is
-not so efficient as the close cast-iron plates.
-
-In addition to the bridges required for the regular public roads, it
-is usually necessary to construct a certain number of occupation or
-private road bridges over and under the line to accommodate portions
-of estates and large properties intersected or severed by the railway,
-and which would be inadequately provided for by ordinary gate
-crossings on the level. The position and description of these
-occupation bridges is generally matter of private arrangement. The
-bridges will be somewhat similar in character to the public road          111
-bridges, but of much less width for the roadway. Those over the
-railway must have the standard span and height adopted as a minimum
-for the other over-line bridges, and those under the railway must have
-the full width on the top for the lines of rails, but will have less
-width between the abutments for the roadway.
-
-
-Foundations.--So much depends upon the soundness and security of the
-foundations of any bridge, viaduct, or large building, that it would
-be almost impossible to devote too much care to the selection and
-treatment. Unless the foundation be firm, the entire structure will be
-exposed to the risk of failure, either in subsidence of masonry,
-giving way of arches, or depression of girders. A small matter
-overlooked during the construction of this part of the work will be
-most difficult to correct or adjust afterwards.
-
-The insistent weight of all structures built of masonry or brickwork
-will cause the mass to settle to a certain extent, according as the
-joints of mortar or cement become compressed by the number of
-superincumbent courses. In a similar manner the gravel and clay of a
-foundation will compress more or less according to its compactness and
-the weight of the structure. No inconvenience will, however, arise if
-the settlement or compression be uniform throughout the entire area.
-
-In ordinary average, dry, solid ground, a good foundation can usually
-be obtained at a moderate depth. The removal of a few feet of the
-surface layers will generally lead to a good hard stratum of natural
-material sufficiently firm to carry the abutments and piers of railway
-bridges and viaducts. Two or more footings are usually adopted so as
-to distribute the weight over an increased area, as shown in Fig. 108.
-
-Where the weight to be carried is considerable, it is better to
-increase the number of the footings, and give them a smaller
-projection, as in Fig. 109, rather than have a lesser number and
-greater projection, as in Fig. 108. There is greater liability of
-fracture of the material in the latter than in the former.
-
-Care must be taken to distinguish between made ground and natural
-ground. Hollows which have been filled in must not be relied upon to
-sustain heavy weights; the material may have been consolidating for
-years, but it is safer to cut through it and found upon the natural
-stratum beneath.
-
-[Illustration: Fig. 109, 108, 110, 111, 124, 113, 114, 115, 125]
-
-Soils of a clayey nature must be dealt with very cautiously. If the       113
-ground be fairly level, and the material firm, a solid foundation may
-be obtained, but the excavated portion should be covered up as quickly
-as possible to prevent any decomposing action taking place upon
-exposure to the open air. The expansive nature of some clays must be
-carefully kept in view, so as to guard against any disturbance in the
-finished foundation. There are some descriptions of shale which when
-first opened out appear to have the solidity of hard rock, and yet,
-after a few days’ exposure to the atmosphere, are changed to the
-consistency of soft mud.
-
-Sand, being composed of such small particles, is almost incompressible,
-and makes an excellent foundation so long as it can be retained in its
-position. Little or no settlement will take place if the sand remains
-undisturbed, but so soon as it comes under the influence of running
-springs, or underground drainage, the fine particles of the sand will
-be gradually but surely carried away with the water, and the entire
-foundation be undermined. The opening out of a neighbouring
-excavation, or the carrying out of some low-level drainage, would
-endanger a construction which otherwise would be solid and permanent.
-
-In many cases of soft ground, more particularly abroad, sand piles
-have been adopted and have given very good results. The system is
-carried out by first driving a large wooden pile down through the soft
-material into the more solid stratum below. The timber pile is then
-carefully withdrawn and the cavity filled with clean sand. The number
-and distance apart of these sand piles will depend upon the nature of
-the ground and description and weight of structure to be carried.
-
-Clean, compact gravel is one of the best materials to build upon,
-being almost incompressible and quite unaffected by exposure to the
-atmosphere. It is easily excavated and levelled off to the surface
-required.
-
-A foundation of rock may be considered in the abstract as the most
-solid base to be obtained, but it must be treated judiciously, and a
-proper surface secured. The outer portion of many descriptions of rock
-consists of blocks or layers of stone partially or entirely separated
-from the main bed, and these, lying in a loose condition, are
-deceptive and treacherous as a foundation base. The exposed rock
-should be carefully examined, and all detached or outlying pieces or
-layers removed before placing any foundation course. Special care must
-be paid to all shelving rock, and a level seating cut into it for the     114
-entire width of the foundation, as shown in Fig. 110.
-
-A thick bed of concrete, as in Fig. 109, makes an excellent foundation
-course. When firmly set it becomes one solid massive base from end to
-end, and prevents the yielding or dropping of masonry at any
-intermediate points.
-
-There are many places in soft, wet ground where instead of attempting
-to excavate all the soft material down to a harder stratum, it is
-better to adopt timber pile foundations, as shown in Fig. 111. The
-size of the piles and their distance from centre to centre must be
-regulated by the description of material into which they have to be
-driven and the weight they have to sustain. Double waling pieces
-should be properly checked and bolted on to the heads of the piles,
-and trimmed or levelled off to receive a double floor of thick planks.
-The spaces round the heads of piles and walings should be filled in
-and levelled up to under side of flooring, with cement concrete.
-
-[Illustration: Fig. 112]
-
-For bridges of moderate span, over soft ground or over shallow fresh
-water, strong cast-iron screw piles can be adopted with great
-advantage. Fig. 112 shows a very usual form of screw pile, made with
-an external screw at the lower end and with a sharp cutting edge to
-facilitate penetration into the ground. The upper portions are made in
-suitable lengths, and all to one pattern and template, for convenience
-in carrying out the work. The screwing into the ground is generally
-effected by means of a capstan or cross-head fixed to the top of the
-first working length of pile, and which is pulled or turned round by
-ropes worked from stationary windlasses. In some cases long bars or
-levers are attached in radiating positions to the capstan-head, and a
-number of men are employed to walk round and round, pushing the
-levers, and in this way screwing the pile into the ground. As the pile
-goes down the capstan-head has to be removed, and additional lengths
-bolted on, until the pile enters a solid stratum, or is considered
-deep enough for the duty it has to perform. The last or top length has
-generally to be cast to a special length to bring the work up to the
-exact height to receive the girders. The core of excavated material
-passes up into the interior of the pile, and in some cases becomes so
-compressed or tight as to require the use of an internal augur to
-remove a portion of it to enable the screwing to proceed. The pile
-shown in Fig. 112 is one of a number which were successfully screwed
-into the ground to depths varying from 42 to 48 feet. A toothed or        116
-serrated edge, as in Fig. 113, is sometimes given to the lower edge
-for screw piles which have to cut their way through a hard stratum.
-
-All bolting flanges should be accurately turned and fitted to ensure
-close, parallel surfaces when bolted together.
-
-The joint shown at A, Fig. 112, is one the writer has used to a
-large extent for the bolting flanges of cast-iron screw piles and
-cylinders. It is very simple in form, readily coated with white lead
-to ensure a water-tight joint, and as the upper length is practically
-recessed, or let into the lower length, the exact continuity of the
-different castings is secured.
-
-Solid screw piles of wrought-iron or steel, similar to Fig. 114, are
-used for some descriptions of work. These are generally made in long
-lengths, in sizes varying from 4 to 8 inches in diameter, and with
-screw blades of wrought-iron or cast-iron fixed in the most secure
-manner to resist the strain produced when screwing into the ground.
-The couplings for these solid piles must be very carefully made, all
-contact surfaces truly faced and fitted, bolts turned, and bolt-holes
-drilled.
-
-Fig. 115 is a sketch of a hollow cylindrical water-jet pile, which has
-been used successfully in cases of light sand. The lower end of the
-pile is made externally in the form of a solid disc, terminating in a
-conical point, having an aperture in the centre to correspond to the
-water-jet. To the top of the pile is secured a tight-fitting cover
-through which a tube passes from a force pump. Water at high pressure
-is pumped into the tube, and as it forces its way out through the
-conical point the sand is stirred up and loosened, and thus allows the
-pile to descend. When the pile has been lowered to a sufficient depth
-the pumps and tube are removed, and the sand settles down into its
-former compact condition.
-
-Great care must be used with the first two or three lengths of any
-screw pile to ensure the pile taking a correct or true vertical
-position. Each series of screw piles should be properly braced
-together to obtain stability under moving loads.
-
-[Illustration: Fig. 116]
-
-[Illustration: Fig. 117]
-
-Hollow cylinders of cast-iron, wrought-iron, or steel form most
-efficient foundations or piers for large bridges over soft ground or
-fresh water of considerable depth. Made open at the bottom, and
-constructed of complete rings, or, if of large diameter, of rings
-built up in segments and securely attached together with water-tight      119
-joints, the cylinder is placed in its proper position on the ground or
-lowered into the water preparatory to sinking. The lower length is
-made with a sharp cutting edge to facilitate penetration. By
-excavating and removing the material round the cutting edge and base
-inside the lower length, the cylinder descends gradually either from
-its own weight or by assisted weights, and length after length is
-added until it is sunk to the depth required. The excavated material
-is filled into buckets and hoisted to the surface by a winch fixed on
-the top length. When sinking in water the working top of the cylinder
-is always kept at a suitable height above the water for convenience in
-removal of the earth or clay from the interior to barges or gangways
-alongside.
-
-Some strata are more favourable for cylinder sinking than others.
-Material of a strong clayey nature admits but a small amount of water
-into the excavation, and a moderate-sized pump will keep the working
-fairly dry until considerable depth has been reached. Some other
-materials are so open that the water cannot be kept down with ordinary
-pumps, and the cylinders can then only be lowered by the pneumatic
-process. This process has been carried out in two methods, one of them
-on the _vacuum_ principle, and the other by air pressure, or, as it is
-termed, the _plenum_ system. With the former method the cylinder is
-placed in position, and an air-tight cap, through which a pipe passes,
-is secured on the top. Powerful air-pumps are then set to work, and
-the partial vacuum thus created in the interior causes the material
-round the cutting edge and base to be loosened and drawn into the
-cylinder, the cylinder at the same time going down or sinking by its
-own weight, or assisted, if necessary, by added weights. The cap is
-then taken off, and the material removed from the interior, the
-operation of exhausting and emptying the interior being repeated until
-the cylinder is sunk to its proper depth. This method has been found
-to work well in strata which contained a large proportion of clay to
-assist in excluding the air and water, but was not nearly so
-successful when applied to material containing stones and large
-boulders.
-
-The _plenum_ process is based on the principle of the diving-bell, the
-water being prevented from entering at the bottom by keeping the
-cylinder full of compressed air. An air-chamber, or _air-lock_, with
-perfectly air-tight joints, is securely fixed to the top or upper         120
-working length of the cylinder, and no access can be obtained to the
-interior of the cylinder without passing through this air-lock, which
-has one lower door or valve opening into the cylinder, and an upper
-door opening out into the open air. Temporary inside staging is formed
-by putting planks across from flange to flange, and placing short
-ladders on these landings for the use of workmen descending or
-ascending. The excavated material is hoisted by a winch, generally
-placed on the landing just under the air-lock. The air-pump is placed
-in some convenient position outside, near at hand, the pressure-pipe
-passing through the air-lock into the interior of the cylinder. Air is
-forced into the cylinder to a pressure sufficient to drive out and
-keep out the water from the interior, and allow the workmen free
-access for excavating the material round the cutting edge and base of
-cylinder. The amount of pressure required will depend upon the depth
-of the working below the level of the water alongside. Men accustomed
-to the process can work without much inconvenience under a pressure of
-20 to 22 pounds per square inch, equal to a depth of 45 to 50 feet;
-but when the pressure exceeds 25 pounds, the duty becomes very trying,
-and is attended with considerable risk. Instances are recorded of men
-working at depths of 105 and 110 feet, necessitating a pressure of
-over 45 pounds per square inch; but it is very questionable whether
-the men exposed to such a severe ordeal were not permanently affected,
-if some of them did not actually succumb.
-
-It will sometimes occur that, after sinking through soft porous strata
-to a considerable depth, a layer of clayey material is penetrated
-sufficiently retentive to keep out the water and permit of the removal
-of the air-lock and the completion of the sinking as an open-top
-cylinder.
-
-When working on the _plenum_ system everything must pass through the
-air-lock, both materials and men. The excavated material is hoisted up
-to the level of the air-lock, the upper and lower doors of which must
-be closed, and the pressure inside the air-lock brought to the same as
-that inside the cylinder by means of a regulating valve. The lower
-door is then opened to admit the excavated material, and then closed
-again to cut off all communication with the interior of the cylinder.
-The upper door is then opened, and the material hoisted out into the
-open air. The same process has to be adopted for the egress of the
-workmen, and the reverse arrangement for the ingress of men and           121
-materials. The shape and dimensions of the air-lock may be varied
-according to circumstances, but the principle will remain the same.
-
-When the cylinder has been lowered to what is considered a sufficient
-depth, it is usually loaded with a certain amount of dead weight in
-the shape of old iron or other convenient material, and allowed to
-remain loaded for some days to ascertain if it will sink any further.
-Should this test be found satisfactory, the dead weight is removed,
-and the interior of the cylinder pumped dry and carefully filled with
-good cement concrete.
-
-Cylinders for foundations are generally made circular in section, that
-form being the most convenient for turning and facing the
-flange-joints. They can, however, be made oval in section, or of any
-section that may be found most suitable for the work required. Figs.
-116 and 117 give the particulars of a double-line railway bridge
-carried on cylinder piers across a river. The detail sketches explain
-the form of cutting edge, flange joint, and method of bracing. This
-bridge is one that was reconstructed and widened from a single-line to
-a double-line bridge. Traffic was carried over on one line while the
-second line was being erected, hence the reason why one strong central
-girder was not adopted.
-
-Cylinders of 7 feet diameter and upwards are sometimes filled with
-concrete in the lower portion, on which is built either a circular
-lining or a solid mass of masonry or brickwork up to the level of the
-girder-blocks. In some cases the cylinders proper, together with their
-concrete filling, terminate a little above the water-level, and upon
-these foundations are erected strong cast-iron columns, plain or
-ornamented in design, to carry the girders and roadway. The cylinder
-itself is generally considered merely as a casing or medium for
-obtaining a foundation, the weight of the superstructure being carried
-on the internal filling or lining.
-
-Caissons constructed of plates of wrought-iron or steel are much used
-for the foundations of large piers in deep water. Practically they may
-be considered as cylinders on a large scale, with the difference that
-whereas cylinders are generally continued up to the under side of the
-girders of the superstructure, caissons are only carried up to a short
-distance above the water-level. A caisson forms a strong water-tight
-iron cofferdam, from which the water can be excluded, and a masonry or    122
-brickwork pier constructed inside. It may be made all in one piece to
-correspond to the form of the pier, or in separate pieces to form one
-whole, each being sunk independent of the other, and connected
-together afterwards. Being built up of plates cut to the proper size
-and shape, it is a very simple matter to rivet on additional tiers of
-plates as the caisson is lowered deeper and deeper into the bed of the
-river. The lower length is made with a cutting edge to penetrate the
-ground; the exterior is made without any projection larger than the
-rivet heads, and the interior is strengthened with T-irons or double
-L-irons at the joints, and strong cross-bracing to resist the
-pressure of the water. About 7 or 8 feet above the cutting edge a
-strongly framed iron floor is riveted to the vertical sides, and
-strengthened by plate-iron under-brackets placed at short distances.
-The excavators work in the space below the floor, and the excavated
-material is passed up through openings formed in the floor at
-convenient points to suit the working. The methods of lowering a
-caisson are the same as for lowering a cylinder. If the pneumatic
-system has to be adopted, then two or more air-tight tubes of liberal
-dimensions (say 5 to 8 feet diameter), according to the size of the
-caisson, must be attached to the floor, and on the top of each of
-these tubes air-locks must be secured for the removal of men and
-materials. The masonry or brickwork of the pier is built upon the iron
-floor, and a portion of this building work is usually carried on
-during the sinking of the caisson to obtain weight to assist in the
-lowering. When down to the proper depth, the space below the floor is
-properly cleared of _débris_ and water, and then carefully filled in
-with cement concrete.
-
-Some caissons are made with vertical sides throughout their entire
-height; others have an outward taper for 15 or 20 feet on the lower
-end. The former are not only simpler in construction, but are more
-easily kept in a vertical position during the sinking. Caissons are
-usually put together in some convenient place near the edge of the
-water, and then conveyed on pontoons to the sites of the piers. Great
-care is required in lowering them into position in the bed of the
-river, and guide-piles, guy-chains, and other appliances are
-frequently necessary to keep them vertical during the sinking.
-
-The form, dimensions, thickness of plates, cross-bracing, and general
-arrangement will depend upon the size and depth of the pier to be         123
-constructed. Caissons for heavy work on difficult or treacherous
-ground require great care, not only in their construction, but also in
-placing them in exact position, and in sinking them correctly to their
-proper depth. A tilted caisson is a most difficult subject to handle,
-and entails heavy expenditure to restore it to a true vertical
-position. By making careful borings, the engineer can ascertain very
-closely the depth to which the caisson will have to be lowered to
-obtain a good firm foundation. With this information the caisson can
-be so constructed that the upper portion, termed the temporary
-caisson, commencing a few feet above the bed of the river, can be
-detached, and removed at the completion of the work from the lower or
-permanent portion sunk below the ground line.
-
-Fig. 118 gives sketches of a wrought-iron plate-caisson applied to a
-deep-water river pier, and lowered to its full depth by the pneumatic
-process; dotted lines show the air-tubes through which the excavated
-material is hoisted and emptied into barges alongside.
-
-Many large and important pier foundations have been constructed on the
-system of brick cylinders or wells, particularly in India, where the
-foundations for large river viaducts have to be carried down to great
-depths through thick deposits of soft material. These wells are built
-upon V-shaped curbs to facilitate the penetration when sinking. Fig.
-119 is a section of a well with a wrought-iron curb, and Fig. 120 is a
-similar well with a wooden curb. The wrought-iron curb is made in
-segments for convenience of transport, the pieces forming the complete
-ring being bolted or riveted together at the site of the foundations.
-The wooden curb is composed of several thick layers of hard wood
-planking cut to the proper shape, and laid with broken joints, the
-whole being bound together with suitable bolts and spikes. In some
-cases the lower or cutting edge of the wooden curb is strengthened or
-protected by a sheathing of wrought-iron plates.
-
-[Illustration: Fig. 118]
-
-[Illustration: Fig. 119, 120, 121, 122, 123]
-
-Well foundations are usually put in when the rivers are at their
-lowest, and reduced to a few small channels in the great width of
-dried-up river bed. This condition enables the greater portion of the
-curbs to be conveniently and accurately placed in position on dry
-ground, or on ground which, although soft and muddy, is not covered
-with water. Should the site of one of the wells occur in one of the
-small channels, the stream can be diverted to one side, and a small       126
-artificial island made to receive the curb above water-level. When a
-curb is fairly fixed in position, the work of building the brick well
-can be commenced. With the wrought-iron curb the triangular cavity
-between the vertical plate and sloping plate must be filled with
-concrete to form a level base for the first course of brickwork. The
-wooden curb being composed of horizontal layers of timber, is ready to
-receive the brickwork without further preparation. To strengthen and
-keep the brickwork firmly tied together, strong wrought-iron vertical
-tie-rods, 1¼ or 1½ inch in diameter, are generally built into the
-work--as shown in the sketches--at distances about four feet apart.
-The lower end of the bottom tier of tie-rods is secured to the curb,
-and the upper end passed through a strong wrought-iron plate-ring,
-which is continuous all round the brickwork. A long deep nut is
-screwed down over the top or screwed end of tie-rod until the
-plate-ring is down tight on the brickwork. The tightening nuts are
-made sufficiently deep to receive the lower ends of a second series of
-vertical tie-rods, which in like manner pass through another
-wrought-iron plate-ring on the next section of brick well, and the
-same arrangement is continued for the full height of the well. The
-lengths of the tie-rods will depend upon the lengths of the section of
-brickwork to be built at a time, and may vary from 10 to 15 feet.
-
-As the work of building proceeds the curb and brick well will sink
-gradually into the ground, and down to a certain depth, varying
-according to the material of the river bed, the weight of the brick
-well itself will effect the penetration and lowering. Beyond this
-depth the lowering must be done by scooping or dredging the material
-from the inside of the well, and placing heavy weights of old railway
-iron or other convenient masses on the top. When one section or length
-of well has been sunk down, then another set of tie-rods are inserted
-into the deep nuts, and another section of brickwork commenced. The
-operation of lowering is rather tedious, as all the weights have to be
-hoisted up on to the top of the length in hand, and piled so as to
-leave space for lifting out the material dredged from the interior;
-and then, when the length has been lowered, all the weights must be
-removed before the brickwork can be resumed on another length. Where
-the river bed consists of soft material, the excavation inside the
-well can generally be effected by suitable dredges or scoops worked       127
-from the surface or top of brickwork. Should trees or other
-obstructive masses be met with embedded in the strata, it will be
-necessary to employ divers to remove them piecemeal out of the way of
-the curb.
-
-When the brick well has been lowered down to the full depth, and is
-thoroughly bedded in a stratum of strong material, the test weights
-should be left on for some time to ascertain if there is any further
-sinking. After all the weights have been removed the bottom of the
-well can be dredged out clean, and the interior filled in with
-concrete to such height as may be considered necessary.
-
-Brick wells must be watched carefully to ensure that they sink down in
-a perfectly vertical position. Any inclination away from the
-perpendicular must be corrected at once by means of guys and struts,
-the same as in sinking iron cylinders. The principal difficulty will
-be with the first 20 or 25 feet.
-
-The diameter of the well will depend upon the weight it has to carry,
-and its height from river bed to under side of girders. The wells may
-be either circular or polygonal in section, and built singly or in
-pairs, as shown in sketches (Fig. 121).
-
-Many piers and abutments of bridges in shallow or moderately deep
-water are built by means of coffer-dams of timber and clay puddle. The
-coffer-dam forms a water-tight wall round the site of the foundation,
-from which the water is pumped out, and the excavation carried down to
-the depth required. In very shallow water it is sometimes sufficient
-to drive only a single row of piles, and form a bank of good clay
-puddle on the outside, as shown in Fig. 122. In deep water it is
-necessary to drive a double row of piles, 3 or 4 or more feet apart,
-and fill in the space between with clay puddle, as shown in Fig. 123.
-The piles for coffer-dam work should be carefully selected, of good
-timber straight, and correctly sawn on the contact faces. Guide-piles
-are first driven in proper line and position round the intended
-foundation. To these strong horizontal double waling pieces are
-securely bolted, one on each side of the guide-pile, one pair near the
-top, and the other pair as low down as can be placed. The sheeting
-piles, which are lowered down between the horizontal waling or guiding
-pieces, are driven as close to one another as possible, being assisted
-in doing so by the sheet-pile shoe, shown on Fig. 124, which is made
-not with a point like an ordinary pile shoe (Fig. 125), but with a        128
-cutting edge slightly inclined, so that in driving the tendency of the
-pile is to drift towards the pile previously driven. Sometimes the
-outer row of piles consists of whole balks, and the inner row of half
-balks; the size of the piles must, however, be regulated by the depth
-and current of the water. When both rows of piles have been completed,
-the space between should be dredged out, and then filled with
-carefully prepared clay puddle. To enable the puddle to adapt itself
-thoroughly to the wooden sides, it is desirable to remove the inside
-walings after all the piles are driven, as any internal projections
-interfere with the proper punning and settling of the puddle. The
-swelling of the puddled clay has a tendency to force apart the two
-rows of piles, and to counteract this as much as possible, iron
-tie-rods should be passed through from side to side every few feet,
-and screwed up against large washers placed on the outside of the
-outer walings. Strong struts or cross-bracing of timber must be placed
-from side to side inside the coffer-dam to resist the pressure of the
-water in the river. This cross-bracing can be removed gradually as the
-work of building progresses upwards, and be replaced with short struts
-wedged in against the sides of the finished courses.
-
-In cases where the ground is soft, and when it is not considered
-prudent to excavate the foundations deeper for fear of disturbing the
-stability of the coffer-dam piles, rows of large, square bearing-piles
-may be driven in the floor of the foundation, as shown in Fig. 111.
-The tops of these bearing-piles must all be sawn off to the same
-level, and a platform of strong double planking securely fixed to the
-piles to receive the foundation course of concrete, masonry, or
-brickwork. The spaces around the tops of the piles and the under side
-of the timber platform should be filled in with good cement concrete.
-
-The interior of the coffer-dam is kept dry by constant pumping, either
-by hand pumps or steam pumps, according to the volume of water finding
-its way into the foundations. When the finished pier or abutment has
-been carried up above the river water-level, the coffer-dam is no
-longer required, and may be removed. Sometimes, to save the timber,
-the piles are drawn by means of strong tackle fitted up for the
-purpose; but in doing this there is considerable risk of disturbance
-to the foundations, and it is better to leave the piles in the ground
-and employ divers to cut off the tops a little above the bed of the       129
-river.
-
-In preparing the design for a large foundation it is absolutely
-necessary to first ascertain by careful borings the description of
-material upon which that foundation must be placed, so as to
-proportion the area of bearing surface to the weight to be sustained.
-Some materials will naturally carry more weight than others, and
-although the engineer cannot always select the material he would
-prefer, he can, however, control the superficial area of the
-foundations. Much valuable information has been obtained both from
-experiments and from comparisons of actual practice, and the following
-memoranda may be useful for reference, as indicating the pressures per
-superficial foot which may be safely put on various materials:--
-
-     Moderately stiff clay                      2½ tons.
-     Chalk                                      4   ”
-     Solid blue clay                            5   ”
-     Compact gravel and close sand              6   ”
-     Solid rock                                12   ”
-
-Doubtless the above weights have been exceeded in many cases, but it
-is better to be on the safe side, and leave a good margin for
-stability.
-
-Large subaqueous foundations for heavy piers and abutments are costly
-and tedious, and especially so when the pneumatic process has to be
-adopted. Special appliances and well-trained, experienced workmen are
-requisite, and if all the men and materials have to pass through the
-air-locks, the progress of the work must necessarily be slow. When the
-foundations have been completed up to the level of the water, the
-construction can be pushed on more rapidly, as the work of
-scaffolding, hoisting, and building, can all be carried on in the open
-air.
-
-Amongst the very many types of arch-work and girder-work adopted for
-railway purposes, the following examples from actual practice may be
-useful for reference:--
-
-[Illustration: Fig. 126, 127]
-
-Fig. 126 represents small 24-foot span, low viaduct arching suitable
-for a line passing through towns or villages, where ground is valuable
-and the area to be covered must be kept as small as possible. The
-arches may be utilized for stables, stores, or roads of communication
-between the lands and properties intersected by the railway. The
-segmental form gives a better headway underneath than the
-semicircular, besides containing less material in the arching proper,
-and requiring a smaller amount of centering. Every precaution should      131
-be taken to prevent water percolating through any portion of the
-arching, or haunching, and a thick layer of good asphalte should be
-placed over the entire upper surface, and carried well up the lower
-portion of the parapet walls, as shown on the sketch. The cast-iron
-pipes with rose heads form a very efficient means of taking away the
-rain-water which filters through the ballast and filling. The pipes
-should be carried down in chases, or recesses, built in the fronts of
-the piers, to protect them as much as possible from injury in the
-yards below. Rose heads, pierced with holes, and surrounded with small
-stones hand-laid, serve well to conduct the water into the pipes.
-Where the arching is of considerable length, recesses or refuges for
-the platelayers may be obtained by substituting a short length of
-cast-iron-plate parapet, instead of the stone or brick parapet, over
-some of the piers, as indicated in the sketch.
-
-Fig. 127 shows a similar description of arching for spans of 30 feet.
-The above two examples represent plain substantial work, but if
-circumstances warrant more external finish, this can readily be added
-without interfering with the general arrangement. In a similar manner,
-if considered preferable, the arches may be made semicircular or
-elliptical.
-
-In the sketches shown of the arched over-line and under-line bridges,
-the arching and coping of parapets are in brick, and the remainder of
-the work in stone. In very many cases brick will be found cheaper and
-more expeditious for arching than stone, unless the quarries turn out
-stone in blocks which can be conveniently trimmed for arching. All
-bricks used for arch-work should be hard and well burnt, and special
-care should be taken in the selection of those to form the under-side
-course, which will be exposed to the atmosphere. For moderate spans
-arches have been successfully constructed of concrete. For this
-description of work the materials should be carefully gauged and mixed
-together, and the finished work should be allowed to stand some time
-on the centres to allow the concrete to become thoroughly set.
-
-[Illustration: Fig. 131]
-
-In Fig. 102, the cutting being deep, almost up to the level of the
-public road, the foundations of the wing walls are built in steps,
-resulting in a minimum of masonry below the finished ground line.
-Where the cutting is shallow, and the public road has to be brought up
-to the bridge on an embanked approach, the greater portion of the wing    133
-walls will have to be built up from the solid or original ground, and
-there will be a large amount of masonry below the finished ground
-line, as indicated in Fig. 128.
-
-In some cases of over-line bridges it is necessary to curve the wing
-walls to correspond to the road which turns off to the right or left
-after crossing the railway, as shown in Fig. 129; or the wing walls
-may have to form two separate curves where the road branches off in
-two directions after leaving the bridge, as shown in Fig. 130.
-
-Fig. 131 shows plan, elevation, and cross-section of an under-line
-arch bridge, considerably on the skew, carrying a railway over a
-river. The wing walls are curved, and very similar in type to some of
-those in preceding examples. The river bed and ground alongside being
-of solid rock, good foundations were obtained at a very moderate cost.
-
-On many railways constructed in the beginning as single lines only,
-the over-line bridges have been built for double line. The additional
-cost in the outset has been small, compared with the great expenditure
-which would be incurred afterwards in reconstructing the bridges to
-suit a double line.
-
-The general arrangement of abutments and wing walls shown in the
-foregoing examples will apply to similar classes of bridges where
-girder-work is adopted instead of arching.
-
-There are many ways of forming the floor or deck of a girder bridge
-intended to carry a railway over a road or stream. In some cases it
-will be imperative to have a thoroughly water-tight floor to prevent
-rain-water percolating through to the roadway below; while in others,
-such as bridges over streams, and secondary roads, this special
-provision will not be necessary, and a lighter and more economical
-floorway can be adopted. A strong wrought-iron or steel-plate
-flooring, with its corresponding filling and ballasting, means not
-only so much additional cost in the flooring proper, but also so much
-additional dead weight to be carried by the main girders.
-
-[Illustration: Fig. 132, 133, 134, 135, 136, 141]
-
-Fig. 132 is a sketch of rolled joist-iron I-girders and timber floor
-frequently adopted for small farm roads and cattle creeps of 10 or 12
-feet span. A beam of timber is fitted in between the two rolled
-joist-irons, and the three pieces securely fastened together with
-strong iron bolts placed about 3 feet apart. These small compound
-girders rest on bearing-plates of wrought or cast iron, and are held      135
-together and to gauge by tie-rods, as shown. The rails are spiked or
-bolted down on to the timber beams, and the flooring formed of strong
-planking.
-
-Fig. 133 shows an arrangement of plate girders for a 16-foot opening
-over a stream. The girders are placed immediately under the rails, and
-are tied together by plate-iron cross-bracing the same depth as the
-main girders. The flooring consists of 4-inch planking laid with
-¾-inch spaces, on which are laid longitudinal rail-bearers 14 inches
-wide by 7 inches thick.
-
-Fig. 134 is a sketch of a somewhat similar arrangement for a
-lattice-girder bridge, 45 feet span, carrying a single line of railway
-over a river. The main girders are tied together by lattice-work
-cross-bracing. The floorway consists of 5-inch planking, laid with
-¾-inch spaces, on which is placed the 14 feet by 7 feet longitudinal
-rail-bearers. Plate-iron outside brackets are riveted to the main
-girders to carry the ends of the planking and light tube-iron parapet.
-
-Fig. 135 illustrates an example of trough girders, constructed to
-carry a double-line railway over a country road 25 feet wide, where
-the space from under side of girder to rail-level is small. The
-girders are constructed in pairs, with short, shallow cross-girders at
-3 feet 6 inch centres, riveted in between them to carry longitudinal
-timbers on which the rails are laid. Bottom plates, 5/8 inch thick,
-unite the two girders for the length of their bearing on the
-abutments, and a similar plate, 9 inches wide, unites them at the
-centre; the remainder of the span is left open to prevent the lodgment
-of rain-water. Three strong tie-rods are placed to keep the girders to
-gauge. Curved wrought-iron ballast-plates are used between the
-running-rails, and plank flooring forms the rest of the covering.
-
-[Illustration: Fig. 137]
-
-Fig. 136 is a sketch of a plate-girder bridge over a country road 28
-feet wide, with the load carried on the lower flange of girder. Three
-main girders carry the double line of railway, the centre one having
-double the strength of each of the outside girders. On the top of the
-cross-girders, strong angle irons are riveted to serve as guides and
-supports for the longitudinal timbers which carry the rails. Every
-third cross-girder has raised ends to give increased lateral stability
-to the main girders. A close cast-iron plate parapet forms a screen to
-the roadway. Wrought-iron ballast-plates are used between the
-running-rails, and the remainder of the flooring is of timber.
-
-Fig. 137 gives the particulars of one 60-foot span of a viaduct           137
-carrying a double line of railway over tidal water. The main girders
-are placed one under each line of rails, and all the four are strongly
-tied together by lattice-work bracing the full depth of the girders.
-The outside footpaths for the platelayers are carried on strong
-brackets, riveted to the main girders. Longitudinal timbers, coped
-with angle iron, are placed as outside guards, alongside each rail,
-for the full length of the viaduct. Wrought-iron ballast-plates are
-placed between the running-rails. The remainder of the footways
-consist of timber planking, laid with half-inch spaces, and covered
-with a layer of small pebbles as a protection against fire.
-
-Fig. 138 shows a very similar arrangement in a viaduct carrying a
-single line of railway across a river. The two main lattice
-girders--66 feet span--are placed at 9-foot centres, to obtain greater
-stability. The cross-girders are extended to carry the outside
-footpaths and handrailing. Outside guards are placed alongside each
-rail as in the preceding example. Wrought-iron ballast-plates are
-fixed all along between the running-rails, and timber planking used
-for the rest of the floorway.
-
-Fig. 139 gives cross-section of a lattice-girder bridge, 82 feet span,
-carrying a single line of railway over a river, with the load carried
-on the lower flange. The cross-girders are placed at 4 feet 3 inch
-centres. Wrought-iron ballast-plates compose the floorway between the
-rails, and timber planking covers the rest of the bridge. Plate
-diaphragms, or stiffeners, of the form shown at A, A, A, A,
-are riveted to the main girders at five places in their length.
-
-Fig. 140 shows cross-section of a lattice-girder bridge of 200 feet
-span, carrying a single line of railway over a river, the load being
-placed on the lower flange. The floorway consists of plate-iron
-cross-girders, spaced at 4-foot centres, on which are placed the
-longitudinal rail-bearers and planking, the latter being covered with
-a layer of clean pebbles for the width between the running-rails. As
-the depth of the main girders was sufficient to admit of overhead
-bracing, strong plate-iron diaphragms, of the form shown on the
-sketch, were riveted to the main girders at every 50 feet. These
-diaphragms thoroughly brace the two girders together, and effectually
-prevent any tendency to side-canting, at the same time imparting an
-effective appearance to the bridge.
-
-[Illustration: Fig. 138, 139, 143]
-
-Fig. 141 shows cross-section of a plate-girder bridge, of 36 feet         139
-span, carrying six lines of way across a street. Strong plated
-cross-girder bracing, at 4 feet 8¼ inch centres, is riveted to the
-main girders, and the top is covered with old Barlow rails, 12 inches
-wide, and weighing 90 lbs. per lineal yard. A layer of asphalte, about
-1½ inches thick, is carefully laid all over the upper surface of these
-rails to make a thoroughly water-tight floor. Clean gravel is placed
-on the top, on which are laid the sleepers and rails of the permanent
-way. Rain-water passes through the gravel into the hollows of the
-Barlow rails, and finds its way into suitable drains provided at each
-abutment. This arrangement not only prevents the falling of drip-water
-into the street below, but permits of the alterations of the lines of
-way, or putting in of cross-over roads on the surface above. The
-outside main girders are made deeper, and are surmounted by close
-cast-iron parapets.
-
-Fig. 142 gives the particulars of a three-span plate-girder bridge,
-constructed to carry a double line of railway over two other railways
-and a canal, the load being placed on the lower flange. Two main
-girders are used for each line of way. Strong plated cross-girders are
-placed at 5 feet 3 inch centres, and on the top of these is laid a
-flooring of old Barlow rails, terminating at the sides with sloping
-wing-plates riveted to the cross-girders and main girders, the entire
-surface being covered with an inch and a half layer of asphalte. Good
-gravel ballast is placed on the top, on which are laid the sleepers
-and rails. One central main girder of sufficient strength would have
-been as efficient as the two central girders, but there was a
-practical difficulty which prevented its adoption. The new girder-work
-was built to replace an old structure of peculiar arrangement, and to
-keep the traffic going on one line there was no alternative but to
-make each line of way complete in itself.
-
-[Illustration: Fig. 140, 144]
-
-Fig. 143 illustrates an example of jack arches in concrete built
-between strong plate-girders. The span of the girders was only 16
-feet, but the opening or roadway was of considerable length, and
-passed under a portion of a busy station yard. The girders are placed
-at 6-foot centres, and tied together in pairs by 1¼-inch tie-rods,
-three to the span, spaces of 6 inches in plan being allowed between
-each set of the rods. The concrete was curved up to the top plate of
-the girder, as shown, and the entire surface covered with a thick
-layer of asphalte, on which were placed the ballast and permanent way.    141
-Brickwork might have been used for the jack-arching, but concrete was
-considered more convenient.
-
-Fig. 144 shows the cross-section of a truss-girder bridge of 123 feet
-span, carrying a double line of railway over a wide thoroughfare, the
-load being placed on the lower flange. There are two main girders,
-each 12 feet 6 inches deep in the centre, and 8 feet deep at the ends.
-Plate cross-girders are placed at 4 feet 6 inch centres, on which is
-riveted longitudinal plate-iron troughing, extending across the bridge
-and terminating at the sides with wing-plates, as shown. The entire
-floor is covered with a thick layer of asphalte previous to filling in
-with ballast to receive the permanent way. Plate stiffeners are
-adopted in this bridge very similar to those in Fig. 139.
-
-Fig. 145 gives plan, elevation, and cross-section of a plate-girder
-bridge of 95 feet span, carrying a double line of railway over a very
-busy street. There are two curved-top main girders, each 10 feet 9
-inches deep in the centre, and 6 feet 7½ inches deep at the ends. The
-arrangement of cross-girders, longitudinal plate-iron troughing, and
-permanent way, is very similar to that in the preceding example, but
-the side wing-plates are carried up higher, and are riveted up to the
-web-plate of main girder, forming continuous stiffeners from end to
-end of the main girders. A light, ornamental, close cast-iron parapet
-is bolted on to the top of the curved, or upper, boom of the main
-girder, the top line of the parapet being carried out parallel to the
-bottom boom of girder. This bridge crosses the street very obliquely,
-and, although cast-iron columns were allowed at the edge of the
-footpaths, the main spans are unavoidably large. When designing the
-above bridge, the writer had to adopt a girder that would form a
-screen, to provide a deck, or floor-way, which would be not only
-water-tight, but also deaden as much as possible the sound or
-vibration of passing trains, and at the same time give some ornamental
-appearance to the girders and parapets. This bridge carries a constant
-service of heavy trains; it is perfectly dry underneath, and is
-remarkably free from noise or vibration.
-
-[Illustration: Fig. 142]
-
-Fig. 146 shows cross-section of a plate-girder bridge of 40 feet span,
-carrying a double-line railway over a street, in a situation where the
-depth from top of rails to under side of girders had to be made as
-small as possible. Three main girders were used, the centre one being     143
-double the strength of each of the outside girders. Instead of
-ordinary cross-girders, transverse plate-iron troughing was adopted,
-very similar in section to the longitudinal iron troughing in Fig.
-145, but stronger. The troughing rested on the angle iron of bottom
-flange of main girder, and was riveted to the vertical web-plates of
-main girders, shallow additional vertical plates being inserted
-alongside web-plates to prevent any drip-water or moisture coming in
-contact with the main web-plates. The entire surface of the troughing
-was well covered with asphalte before filling the hollows with gravel
-ballast. An ordinary transverse wooden sleeper was placed in each
-hollow, and on these sleepers the rails were secured as shown. In this
-case--as in others of transverse troughing--the rain-water had to be
-conveyed away from the hollow of each trough by a separate outlet into
-longitudinal gutters shown at A, B, and continued on to the
-abutments.
-
-Transverse troughing is always more troublesome than longitudinal
-troughing, as both ends of each trough must be effectually closed to
-prevent the drainage water leaking out on to the web-plates, or angles
-of the main girders. With longitudinal troughing the water is readily
-carried away from each hollow, to cross drains constructed at the
-piers, or abutments.
-
-Fig. 147 shows cross-section of a truss-girder bridge, 120 feet span,
-carrying a single line of railway over a river. The cross-girders are
-placed at 10-foot centres to correspond to the vertical members of the
-main truss-girder. Longitudinal plate-iron rail-girders are riveted in
-between the cross-girders, and the entire floor is covered with curved
-wrought-iron ballast plates, as shown. The rails are carried on
-longitudinal timbers, which are bolted on to the rail-girders. Angle
-iron brackets, riveted on the top of the cross-girders, keep the rail
-timbers in position and gauge.
-
-[Illustration: Fig. 145]
-
-In each of the above examples, where longitudinal rail timbers are
-adopted, flange rails are shown, as many engineers prefer to have a
-continuous bearing for the rails on bridges, in case of rail fracture.
-There is nothing, however, to prevent the chair road being laid on
-longitudinal timbers, and for this purpose the writer has used chairs
-of the ordinary pattern, specially cast with side lugs to grip the
-timber, as shown in Fig. 148. Chairs of this form have a very firm        145
-hold on the longitudinal timber, and the side lugs check any tendency
-of the splitting or opening of the wood when putting in the spikes or
-screw bolts.
-
-Fig. 149 shows cross-section of a plate-girder over-line bridge, 32
-feet span, carrying a private road, 12 feet wide, over a double-line
-railway. The road traffic being small, the floorway was constructed of
-creosoted planking carried on rolled I-iron cross-girders placed at 3
-feet 8 inch centres, and riveted to the main girders. The horse-tread
-track was provided with a second layer of planking, laid transversely,
-to take up the wear, cross battens, 4 inches by 2 inches, being placed
-at 12-inch centres, and sand spread between to give good foothold. A
-light lattice-work parapet was bolted on to the top of the main
-girders.
-
-Fig. 150 gives cross-section of a plate-girder over-line bridge, 30
-feet span, carrying a private road, 20 feet wide, over a double-line
-railway. The main girders are tied together by lattice-work bracing,
-spaced at 7-foot centres. Curved wrought-iron plates are laid across
-from girder to girder, and butt against a narrow horizontal plate,
-which forms part of the upper boom. The curved plates are riveted on
-to the top of girder, and form a continuous iron floor, or deck, from
-side to side of the bridge. Upon this iron floor is laid an ordinary
-asphalte roadway. The outside girders are made deeper, and carry an
-ornamental cast-iron parapet. In some bridges of a similar
-construction, the roadway is formed of creosoted wooden block paving,
-on a foundation of asphalte.
-
-[Illustration: BRIDGE CARRYING THE D. W. AND W. RAILWAY (LOOP LINE)
-OVER AMIENS STREET, DUBLIN. [_To face p. 144._]
-
-[Illustration: Fig. 146, 147, 158, 159, 148]
-
-Fig. 151 shows cross-section of a plate-girder over-line bridge, 28
-feet span, carrying a public road, 35 feet wide, over a double-line
-railway. The main girders, 2 feet 4 inches deep, are placed at 5 feet
-2 inch centres, and are tied together by plate-iron cross-bracing 2
-feet deep. Jack-arches of brickwork, 9 inches thick, are built in
-between the main girders, the haunching being filled in with concrete.
-The entire surface is covered over and made watertight with asphalte,
-on which is laid the metalling of the roadway. The outside girders are
-made considerably deeper, and have strong cast-iron-plate parapets
-bolted on to the top booms. There is no doubt that jack-arching of
-brickwork or concrete makes a very strong and permanent floorway, but
-its dead weight is very great, and its adoption is not to be recommended  147
-where iron or steel plate troughing can be obtained at a moderate
-price.
-
-Fig. 152 gives cross-section of plate-girder over-line bridge, 41 feet
-6 inch span, carrying a public road, 25 feet wide, over three lines of
-way. Two main girders are used, of sufficient depth to form parapets
-or screens for the finished roadway. Plate cross-girders, placed at 6
-feet 6 inch centres, are riveted to the web-plate and lower angle
-irons of main girders; and on these is placed a flooring of plate-iron
-longitudinal troughing to carry the metalled roadway.
-
-Fig. 153 gives the particulars of a plate-girder over-line bridge,
-carrying an important public road, 35 feet wide, over several main
-lines and sidings. The carriage-way is carried by two girders placed
-at 25-foot centres, and on the lower boom of these are riveted
-lattice-work cross-girders to receive the plate-iron longitudinal
-troughing and roadway. The footpath girders are set at a higher level,
-and the load placed on the lower flange. The curved side brackets
-merely act as bracing between the carriage-way girders and footpath
-girders. A cast-iron-plate parapet is bolted on to the top of each of
-the footpath girders, making a close screen, 6 feet high, above the
-footpath. Lattice-work cross-girders were adopted for the convenience
-of supporting small water mains and gas mains below the road-level.
-The roadway is formed of ordinary metalling, and the footpaths of
-asphalte pavement; the kerbing is of granite, and the side
-water-tables of crushed granite concrete.
-
-[Illustration: Fig. 149, 150, 151, 152]
-
-Fig. 154 is a cross-section of a small uncovered lattice-girder
-footbridge 41 feet span, and 5 feet wide, suitable for small roadside
-stations. The top and bottom flange consist each of two angle irons,
-those in the bottom flange being placed table side upwards, so as to
-bring the entire section of both angle irons fairly into play, and
-also to provide a better bearing for the channel-iron cross-girders
-which carry the planking of the footway. When planking is carried on
-the inside of light angle iron, as in Fig. 155, a severe strain is
-produced at the point A; this is entirely obviated by placing the
-bottom angle irons table side upwards, as in Fig. 156. Three of the
-channel-iron cross-girders are extended outwards, and to the ends of
-these are riveted tee-iron stiffeners to steady the main girders. In
-some cases stamped, or ribbed, wrought-iron plates are used for a
-footway, but, although more durable, they do not give such a secure or    149
-agreeable foothold as timber. The ascent or descent of the bridge may
-consist either of steps and landings, or of ramps, according to
-circumstances or expediency. Sometimes these bridges are made with
-curved tops, terminating in steps when nearing the steps, or ramps. It
-is very questionable whether such an arrangement is a good one or a
-safe one. There is always a feeling of insecurity when walking over a
-sloping surface broken up by steps, and experience points out that it
-is better to continue the footway level right across to the place
-where the passenger must change his direction to go down the stairs or
-ramp.
-
-Fig. 157 gives cross-section of a covered lattice-girder footbridge,
-62 feet 6 inches span, and 10 feet wide, suitable for an important
-station. The upper boom of girder consists of two angle irons and top
-plate, and the bottom boom of two channel irons. The cross-girders are
-rolled joist-irons resting on the top tables of the channel irons.
-Four of the cross-girders are extended outwards, and carry plate-iron
-outside vertical brackets to stiffen the main girders. Three-inch
-longitudinal planking is laid down from end to end of the bridge, and
-on this is laid 1¼-inch transverse flooring, in narrow widths, to form
-the walking deck. The footbridge is lighted from the sides by
-continuous glazed sashes fixed in strong wooden framework, as shown.
-The roof is covered with canvas bedded in white lead, and painted in
-the same way as an ordinary carriage roof.
-
-The above examples of under-line and over-line bridges are given more
-with a view of illustrating some of the many different descriptions of
-flooring, rather than to point out or suggest the type of main girder
-to carry the load. The description and size of the main girders can be
-varied to suit the span of the bridge, the requirements of the
-traffic, and the opinion of the designer. For spans up to 50 feet it
-will generally be found that web-plate girders are both simpler and
-cheaper than lattice or truss girders; at the same time, there are
-occasions where plate girders can be advantageously adopted for very
-much larger spans, as, for instance, in the example given in Fig. 145,
-where the deep plate girders form a most efficient screen.
-
-[Illustration: Fig. 153]
-
-Figs. 160 to 194 give diagram sketches of a few out of the many forms
-of open, or truss, girders which have been adopted for large spans.
-There are many types from which to make a selection, each one
-possessing its own special features and advocates. In working out the     151
-details of any, or all of them, there are some points which should
-always be kept in mind when deciding the distribution of material in
-the main booms. Rain-water, or moisture of any kind, is the great
-enemy of wrought-iron or steel work, and therefore the plates, angles,
-tees, or channel sections, should be so arranged as to afford the
-least possible facility for the collection or lodgment of water. With
-open, level booms, as in Figs. 137, 139, 140, 144, and 145, the
-rain-water cannot collect, but runs off at the sides, and the plates
-are quickly dried by the sun and wind. With trough booms, as in Fig.
-158, the collected rain-water can only get away through holes drilled
-for the purpose in the bottom plates. These holes are liable to become
-choked up, but even when open they rarely carry off all the
-accumulated water; some of it remains to corrode the plates, and is
-only dried up by evaporation. The inside of trough booms should be
-constantly inspected, and the exposed plates more frequently painted
-than the rest of the girder. In a similar manner, in small double-web
-lattice girders, with the lattice-bars inserted between two angle
-irons, as in Fig. 159, the rain-water finds its way into the spaces at
-A, A, in spite of the most careful packing or filling with cement
-or asphalte. Numbers of small girders of this latter type have had to
-be taken out after a comparative short life, in consequence of the
-great corrosion and wearing away of the lower ends of the lattice-bars
-and angle irons into which they were inserted.
-
-It is most essential, also, that all portions of the girder-work
-should be conveniently accessible for inspection and painting.
-Complicated connections, and parts which are difficult to examine, are
-liable to be overlooked, or, at the best, only painted in a very
-imperfect manner. Neglected corners soon create deterioration, the
-paint scales off, corrosion commences, and the working section is
-gradually reduced. A discovered weakness in some of the important
-parts points to an early condemnation of the entire structure. The
-difficulty of access to the interior of box or tubular girders,
-especially those of small or moderate dimensions, is a great objection
-to that type of girder. Experience has pointed out that open girders,
-free and exposed to the light and air, can be so much more effectually
-inspected and painted.
-
-[Illustration: Fig. 154, 155, 156, 157]
-
-[Illustration: Fig. 160, 161, 162, 163, 164, 165, 166, 167, 168]
-
-[Illustration: Fig. 169, 170, 171, 172, 173, 174, 175, 176]
-
-[Illustration: Fig. 177, 178, 179, 180, 181, 182, 183]
-
-[Illustration: Fig. 184, 185, 186, 187, 188, 189, 190, 191]
-
-[Illustration: Fig. 192, 193, 194]
-
-Perhaps one of the most anxious tasks which falls to the lot of an
-engineer is the renewal of under-line bridges and viaducts on a
-working line. On a new line in course of construction the entire site     158
-of the work is at the disposal of the erectors, and the building of a
-bridge or viaduct can be carried on with a freedom which cannot be
-obtained on an open line. On a working railway, the train service must
-be kept going, irrespective of renewals, and very often the best that
-can be done is to reduce the double line to single line working at the
-site of the operations. It is not always expedient or possible to make
-a temporary bridge and diverted line for traffic purposes, as the
-expenditure to be incurred might be too great to warrant the outlay,
-or there may be local difficulties to effectually prevent the
-introduction of a provisional structure. The taking down of one half
-of the old structure may necessitate the removal of stays and bracing
-affecting the stability of the half remaining to carry the traffic,
-and thus render temporary shoring and bracing necessary. The erection
-of the new work in such a limited space has to be watched with great
-care; all cranes, lifting appliances, and scaffolding must be kept
-clear of vehicles moving over the running-line, and very frequently it
-is found prudent to cease erecting operations during the passage of a
-train.
-
-In very many cases of renewals, the description and arrangement of the
-old structure will materially influence or control the design for the
-new one, and the details of the latter must be schemed out so as to
-disturb as little as possible the stability of the old work remaining
-as the working road.
-
-The following list gives the lengths of the main spans of some railway
-bridges, and may be found useful for reference:--
-
-  LENGTHS OF MAIN SPANS OF SOME LARGE RAILWAY BRIDGES.
-
-  -----------------------------------+-------+----------------
-           Name.                     | Span. |  Description.
-  -----------------------------------+-------+----------------
-                                     | feet. |
-  Forth Bridge                       | 1,710 | Cantilever.
-  Niagara                            |   821 | Suspension.
-  Sukkur                             |   820 | Cantilever.
-  Poughkeepsie, U.S.A.               |   548 | Cantilever.
-  Douro                              |   525 | Arch.
-  St. Louis                          |   520 | Arch.
-  Cincinnati                         |   515 | Linville truss.
-  Haarlem                            |   510 | Arch.
-  Kuilemburg                         |   492 | Lattice bow.
-  St. John’s River                   |   477 | Cantilever.
-  Niagara                            |   470 | Cantilever.
-  Britannia                          |   460 | Tube.159
-  Ohio River,  Pennsylvania          |   442 | Pratt through truss.       159
-  Saltash                            |   434 | Tube and girder.
-  Hawkesberry Viaduct                |   410 | Compound truss.
-  Conway                             |   400 | Tube.
-  Vistula                            |   397 | Lattice.
-  Spey River, Garmouth, N.B.         |   350 | Bowstring.
-  St. Laurence                       |   330 | Tube.
-  Hamburg                            |   316 | Double bow.
-  Cologne                            |   313 | Lattice.
-  Runcorn                            |   305 | Lattice.
-  Sunderland                         |   300 | Bowstring.
-  Rondout Bridge, Buffalo            |   264 | Pratt through truss.
-  Newark Dyke (New)                  |   259 | Lattice bow.
-  Tay Bridge (New)                   |   245 | Lattice bow.
-  Ohio River, Louisville             |   245 | Fink truss.
-  Beaver Bridge, Pennsylvania        |   230 | Pratt deck truss.
-  Craigellachie Bridge               |   200 | Lattice.
-  Rohrbach Bridge, St. Gothard River |   197 | Wrought-iron arch.
-  Windsor Bridge                     |   187 | Bowstring.
-  Victoria Bridge over Thames        |   175 | Wrought-iron arch.
-  Shannon River Bridge               |   165 | Bowstring.
-  Carron Bridge over Spey            |   150 | Cast-iron arch.
-  Preston Viaduct                    |   102 | Cast-iron arch.
-  Trent River Bridge                 |   100 | Cast-iron arch.
-  -----------------------------------+-------+----------------------
-
-
-Retaining Walls.--Instances frequently occur during the construction
-of a railway where it is advisable, if not absolutely necessary, to
-substitute retaining walls in preference to forming the slopes of
-cuttings and embankments.
-
-The excavation of a cutting may be greatly reduced in quantity by
-introducing low retaining walls, as in Fig. 195, and the saving in the
-material to be removed will be all the more important in those cases
-where cutting is in excess of embankment.
-
-The amount of filling for an embankment and the land on which it has
-to be formed may both be considerably diminished by building a low
-retaining wall, say 6 or 7 feet high, at the foot of the slope, as
-shown in Fig. 196. Such a retaining wall makes a most efficient fence
-and well defined boundary of property.
-
-[Illustration: Fig. 195, 196, 197, 198, 199, 200, 201]
-
-The policy of adopting low retaining walls in cases like the above        161
-will depend mainly upon the cost of building materials as compared
-with the cost of earthwork and land.
-
-Where land is very valuable, and where residential property, streets,
-or roads must be interfered with as little as possible, the retaining
-walls may have to be carried up to the level of the original surface
-of the ground, as in Fig. 197, which is shown as for a cutting 25 feet
-deep. The walls may be built of masonry, brickwork, or concrete, or a
-combination of them, and the dimensions or thickness will depend upon
-the description of material to be supported. Weeping holes, or small
-pipe drains, should be formed in the walls, a little above formation
-level, to take away any water which may collect at the back.
-
-Where the cutting is through soft, wet, treacherous clay, liable to
-slip or expand, it may be necessary to insert arched thrust girders
-extending from side to side, as in Fig. 198, so that the outward
-pressure against the one wall may counteract against the outward
-pressure of the other. The thrust girders should be placed at from 10
-to 15 feet centres, and be well braced together in plan to enable them
-the better to resist any tendency of bulging out of the walls.
-
-A similar arrangement of high retaining wall may be introduced in
-embankment to lessen the encroachment on streets or public roads, as
-shown in Fig. 199.
-
-In making a railway through thickly populated towns, it is generally
-preferable to construct the line on arches rather than on earthwork
-filling between two high retaining walls. The numerous openings are
-available for future streets, or means of communication from one side
-to the other, and the arches themselves can be profitably utilized for
-stables, stores, offices, and workshops.
-
-Fig. 200 shows a narrow rocky pass with deep rapid river on the one
-hand and high cliffs on the other, the only available ledge being
-already occupied by a public highway. By building a retaining wall, as
-indicated on the sketch, and excavating a little out of the cliff,
-space may be obtained for a line of railway; or the arrangement may
-have to be reversed, and the retaining wall for the railway built
-along the margin of the river, as in Fig. 201.
-
-In both the cases, Figs. 200 and 201, not only must there be a number
-of weeping holes left in the lower part of the wall, but there must be
-sufficient well-built drains and culverts under the filling and through   162
-the wall to carry away all ordinary or flood water coming down from
-the cliffs and hills above. Where a retaining wall is built along the
-margin of a river, the lower portion, which will be in contact with
-the water when the river is full, should be constructed of selected
-large heavy stones to withstand the scouring action of the water, and
-any brushwood or floating timber which may be brought down by flood
-water.
-
-Where retaining walls are built to support wet clay, or in embanked
-places on wet side-lying ground, the efficiency of the work will be
-much increased by constructing a layer, two or three feet in
-thickness, of dry, flat, bedded stones carefully hand-laid, from the
-foundation to the top of the wall, as shown in Fig. 199.
-
-These dry stones form a continuous vertical drain to take away water
-from any part of the earthwork down to the outlets left in the lower
-portion of the wall.
-
-The building of retaining walls entirely of dry stone is very
-questionable economy, and entails a constant expenditure in
-maintenance and renewal. The working out of one stone loosens the
-surrounding portion of the wall, and if not at once repaired, a length
-of the wall will fall down, bringing with it a large quantity of the
-earthwork.
-
-If readily obtained, large heavy stones should be selected for the
-coping of retaining walls, so as to minimize as much as possible the
-chance of their disturbance or displacement. Where lighter stones have
-to be used, or bricks laid on edge, they should be bedded and pointed
-in cement.
-
-In many places it is necessary to form wide and massive foundations of
-concrete on which to build the retaining wall; and in some cases of
-soft, treacherous ground, timber piling may be necessary.
-
-
-Tunnels.--It would be difficult to assign a date to the first
-examples of subterranean works constructed for utilitarian purposes.
-Nature had furnished so many grand specimens of caves, grottoes, and
-underground passages formed in the solid rock, that man soon grasped
-the principle, and essayed to carry out similar works on his own
-account. The early attempts would probably be limited to forming
-places of shelter, storage or security. Advantage would be taken of
-those rocks which from their locality, accessibility, and compactness
-of material, promised favourable results. The appliances being few and
-primitive, the work of construction would be laborious and slow. So       163
-long, however, as the workers restricted their operations to the solid
-rock, they had merely to contend against the hardness of the material,
-as the opening or passage-way, once made, required no further support
-or attention; but as the wave of progress swept onward, man was
-compelled to deviate from the lines originally followed by nature, and
-had to form his subterranean pathway through softer material, where
-the workings required substantial support. The search for minerals of
-various kinds led to the driving of long headings or galleries
-underground, and as these had frequently to penetrate through strata
-of a soft and yielding character, strong timber framework had to be
-introduced to afford stability to the works, and safety to the
-workers. For ordinary mining operations, strong rough timber supports
-may meet all requirements, and may last until the heading is worked
-out and abandoned; but for subterranean passages or tunnels which are
-intended to form permanent means of communication, the strongest and
-most durable materials must be used to protect the interior as far as
-possible from deterioration or decay. Heavy timbering might be
-sufficient for mere temporary purposes, but substantial masonry or
-brickwork side walls and arching became necessary for permanent work
-in those portions where the tunnel required artificial support.
-
-The first tunnels of any importance were most probably those
-constructed for canal purposes. Many of them were of considerable
-magnitude, and in some instances were from two to three miles in
-length. They were substantially lined with masonry or brickwork at all
-places where the tunnel passed through soft material or loose rock,
-and from the solid nature of the work, and the many years they have
-been in existence, they thoroughly testify to the ability of the
-constructors.
-
-The introduction of railways involved the making of a large number of
-tunnels, perhaps more so in the beginning, when it was thought that
-the use of the locomotive would be confined to very moderate
-gradients, and when engineers hesitated to adopt the steeper inclines
-and sharper curves which form the practice of modern times. Another
-element of consideration also consisted in the fact that the first
-railways were designed to connect the most populous and busiest
-districts, where the prospects of heavy traffic would appear to
-warrant a large outlay for works of construction. As the system spread
-and railways extended further away from the important centres, the        164
-probabilities of traffic would become less promising, and efforts
-would be made to keep down cost of construction, and avoid tunnel work
-as much as possible.
-
-It is not easy to define where cutting should end and tunnelling
-begin. There is no practical difficulty in making a cutting 50, 60, or
-70 feet deep, with slopes to suit the material excavated, and the
-estimated cost per yard forward may even compare favourably with the
-cost of average tunnel-work. But there are other questions which must
-be kept in view--the time required to form the cutting, the space to
-be obtained on which to deposit the enormous quantity of excavated
-material, and the probable difficulty in obtaining the large area of
-land necessary for the cutting.
-
-Before deciding the actual position of a tunnel, both as to line and
-level, it is necessary to obtain the most reliable information
-possible regarding the strata through which it has to pass. In
-addition to the geological indications on the surface and in the
-locality, borings should be made, and trial holes or shafts sunk along
-the proposed centre line of the work, and from these an approximately
-accurate longitudinal section can be laid down on paper, showing the
-respective layers of material to be cut through, and the angle at
-which they lie. With these particulars before him, the engineer may,
-in some cases, consider it more prudent to change the position of the
-tunnel in preference to incurring specially difficult or tedious work
-in dealing with some recognized unfavourable material. Occasionally
-the route may be slightly varied and better material obtained, but
-very frequently there is little to be gained except by a wide
-deviation from the original line.
-
-Solid rock, except for the slow progress, is perhaps the most
-favourable material for tunnelling, as the timbering, side walling,
-and arching can be almost, if not entirely, dispensed with.
-
-Loose rock, although more readily removed, necessitates strong
-timbering to prevent large masses breaking away and falling into the
-tunnel.
-
-Some clays are very compact and tenacious, and will stand well with
-moderate timbering, but even these should not be left long before
-following up with the side walls and arching.
-
-Many clays give much trouble by expanding, or swelling out, when the
-excavation penetrates the layer, and although extra strong timbering      165
-may be used, and be placed closer together, the logs and planks are
-frequently bulged out and broken by the action of the clay. Specially
-strong supports are required for this description of clay, and extra
-thickness of material in the permanent work of side walls and arching.
-
-Solid unbroken beds of chalk are not difficult to cut through: the
-material is easy to work, and the excavation will stand with ordinary
-timbering; but where the chalk is broken and intersected with deep
-pockets of gravel and sand, the operations are very much impeded. The
-loose material, once set free by cutting through the confining barrier
-of chalk, will quickly fall into and fill up the excavation if not
-held back by strong timbering. Side walls and arching are generally
-necessary for tunnels through chalk.
-
-Soft wet clay, quicksands, or other strata having springs of water
-percolating through them, are serious obstacles in the way of
-expeditious tunnelling. No sooner is one cube yard of this soft
-material removed than another slides down, or is washed down, to take
-its place. When once the excavation taps the water-bearing strata,
-large volumes of water will find their way into the workings, and must
-be conveyed away to the mouth of the tunnel, or pumped up through the
-nearest shaft. The timbering of the sides and roof through this
-description of working is very tedious, and attended also with a
-considerable amount of risk. The absence of really solid ground on
-which to place or shore up the supports, taxes the skill of the
-excavators, and very often, when a short length has been made
-apparently secure, it will come down with a run, compelling all hands
-to beat a hasty retreat. The permanent lining through such treacherous
-material should follow the excavation very closely, and special care
-should be exercised in building the walls, arching and invert.
-
-In the excavation through stratified rocks it is necessary to note
-carefully the lie of the strata, whether horizontal, vertical, or
-shelving, as with each one the excavators are exposed to risks,
-against which every precaution should be taken. A large horizontal
-slab of solid-looking rock will suddenly break and fall down without
-any warning. A heavy mass from a vertical layer, perhaps unkeyed, or
-loosened, by an adjacent blasting operation, drops down when least
-expected; and pieces from the high side of the shelving layers detach
-themselves and slide into the working in a most unaccountable manner.
-
-No attempt should be made to carry a tunnel through material which has    166
-been disturbed or at all affected by any natural slip or cleavage, as
-although the strata may be hard and compact in themselves, they have
-really no solid or fixed foundation. The sliding away, once initiated,
-is certain to continue, and, accelerated by the tunnelling operations,
-will most likely, sooner or later, crush in the tunnel and sweep away
-every vestige of the work. Amongst the great mountain ranges these
-natural disturbances are by no means rare, and it will be wiser to
-keep away from their locality, even at the expense of a longer tunnel.
-Unfortunately, instances are on record of tunnels made, or in course
-of construction, through hillsides which had already commenced to
-slide away from the more solid rock, and the ultimate results were a
-further sliding away and total destruction of the work.
-
-The lower slopes and outlying portions of high mountains are the most
-exposed to these natural slips, and they should be most carefully
-studied before commencing any tunnelling operations through them.
-
-To facilitate drainage, it is essential that a railway tunnel should
-be laid down with a gradient or gradients falling in the direction of
-one or both ends of the tunnel. In nearly all tunnels a considerable
-amount of water finds its way in through the weeping-holes left for
-that purpose in the side walls, and must be carried away in suitable
-drains. If the quantity of water be small, ordinary water-tables, one
-on each side, may be sufficient; but for large volumes of water it
-will be necessary to build substantial side-drains, or an ample
-culvert below the level of the rails.
-
-The gradients in a tunnel should be moderate, and not by any means
-excessive, or likely to tax the hauling powers of the locomotives.
-When an engine is working nearly to the utmost of its power on a steep
-tunnel incline, and the speed has become very slow, the exhaust
-vapours or gases from the funnel strike the arching with great force,
-and are deflected down on to the footplate in such dense volumes as to
-almost suffocate the driver and fireman. The writer will never forget
-two or three trying experiences in foreign tunnels, when he and the
-engine-staff were compelled to leave the footplate and climb forward
-to the front of the funnel, leaving the engine to work its way alone.
-Except for very short tunnels it is wiser to have easy inclines, and
-to restrict the steep gradients to the open line, where the very slow     167
-travelling, or even the coming to a stand from “slipping,” may not
-produce unpleasant or alarming consequences.
-
-In tunnels of any length it is usual, where possible, to construct
-shafts extending from the surface of the ground overhead down to the
-tunnel below. These shafts serve the double purpose of enabling the
-excavation to be carried on at an increased number of faces, and act
-as permanent ventilators after completion. In some cases the shafts
-are sunk exactly over the centre line of the tunnel, in others a few
-yards away from the centre line. The latter arrangement, if not quite
-so convenient for hoisting material while carrying on the excavations,
-has certainly the great after advantage that anything falling or
-maliciously thrown down the shaft cannot strike a passing train. The
-short side-gallery, or space between the tunnel and the shaft,
-provides a good refuge for workmen employed in repairs, and a
-convenient site for storing a few materials advisable to keep on hand.
-
-Occasionally favourable opportunities present themselves for making
-horizontal shafts. For a portion of its length the tunnel may be
-located at no very great distance from the precipitous sides of some
-deep mountain ravine, or run near to the cliffs on the sea-coast, and
-advantage can be taken to drive a lateral heading or gallery through
-which the material from the tunnel excavation may be conveyed and
-thrown out into the gorge or seashore below.
-
-In many cases the surface of the ground rises so abruptly from the
-faces of the tunnel and ascends to so great a height, that shafts of
-any kind are entirely out of the question, and the whole of the work
-must be carried on from the two ends. The rate of progress is
-consequently much slower, and the ventilation more difficult. In a
-shaftless tunnel of considerable length, and with a frequent train
-service, the question of providing suitable appliances for promoting
-artificial ventilation is of the utmost importance.
-
-When the centre line of the tunnel has been accurately set out on the
-ground, and the levels of the different parts of the work decided, the
-construction of the shafts and the driving of the headings can be
-commenced. Working shafts intended to serve for permanent ventilation
-are generally made nine or ten feet or more in diameter, and are
-usually lined with substantial brickwork or masonry. When the well-like   168
-excavation has been carried down a few yards, or as far as it can be
-taken without the risk of the earth falling in upon the sinkers, a
-strong curb of hard wood or iron of the same diameter as the finished
-shaft is laid down perfectly level and to exact position, and on this
-curb the ring or lining of brickwork or masonry is built up to the
-level of the ground. The first length finished, the excavation
-downwards is resumed, and the interior lining continued, either by
-allowing the first length to slide down as the material below is
-gradually removed, and building further lining on the top, or by
-excavating and propping up the curbing with strong timbers below. When
-working to the latter method, stout wooden props of convenient length,
-stepped on to sole-pieces, are adjusted to the under side of the
-wooden curb above, the material is then removed for the thickness of
-the brickwork or masonry, and another curb accurately set to level and
-position; on this is built a length of lining up to the first curb.
-
-This work of under-building or under-pinning must be carried out with
-great care and in segments; no props must be removed until the curb
-immediately above is well supported by the new lining, and the inside
-of the lining must be watched and tested to prevent any tilting. All
-spaces at the back of the work must be filled in and well packed with
-hard dry material. As the shaft is continued downwards the mode of
-working may have to be varied; different descriptions of material may
-be encountered, and blasting, shoring, and pumping may each in turn be
-necessary.
-
-When down to the full depth, the lower length of the shaft will have
-to be securely supported by strong timbers, until it can be properly
-built into and incorporated with the arching of the tunnel or side
-gallery.
-
-The completion of the shaft enables the workings to be commenced on
-each side, the excavated material can be hoisted to the surface, and
-building material lowered down. When the tunnel works are finally
-finished, the lining of the shaft should be carried up until it is 15
-or 20 feet above the level of the surface of the ground, and a
-dome-shaped iron grating placed on the top as a protection against
-stones or other articles which malicious persons might attempt to
-throw down the shaft.
-
-Some shafts are only intended for the temporary purpose of lifting the
-excavations from below, or lowering building materials down, and when     169
-the work is completed they are filled in again and closed. These
-service shafts are generally made square in section, and are merely
-lined with wood. Strong vertical timbers are placed at the four
-corners, to which horizontal double cross-pieces are bolted, thick
-planking being placed vertically at the back of these cross-pieces to
-support the sides of the excavation.
-
-The _heading_ of a tunnel is a narrow passage or gallery cut
-through from end to end of the works in the direction of the centre
-line. Where there are shafts, the cutting of the heading can be pushed
-on from several points, and be completed much more rapidly than when
-the working is restricted to the two ends. Headings are usually made
-just sufficiently large for the miners to work, say about 5 feet 6
-inches high by about 3 feet wide, the object being rather to expedite
-the driving of the driftway than to remove large masses of material.
-They must be set out with great accuracy, and be constantly checked as
-the driving is in progress. When completed from end to end, the centre
-line can be checked throughout, and the course actually taken compared
-with the course intended. If there has been much variation in the
-narrow pioneer pathway, either in line or level, the amount of the
-divergence must be rectified when ranging the final centre line for
-the full-size excavation.
-
-Tunnels cannot always be delayed until the heading is cut through for
-the entire length. In many cases the heading, the full-size
-excavation, and the permanent lining have all to be carried on at the
-same time, but as the work of the heading is smaller in extent, that
-portion of the operations can usually be kept well in advance of the
-others. The critical moment arrives when the headings from opposite
-directions meet, as any deviation or want of coincidence must be
-adjusted in the portion of the tunnel still remaining to be opened out
-to full size. Some tunnels of moderate length have been constructed
-without any heading at all, the excavation being taken out to the full
-dimensions from the commencement.
-
-The heading of a tunnel assists not only in the correct alignment of
-the work, but furnishes at the same time an accurate knowledge of the
-strata passed through. It is also of service for ventilation,
-communication, and drainage.
-
-In some cases the heading is driven at the bottom of the tunnel
-section, as in Fig. 211, and in others at the top, as in Figs. 202 and    170
-204. Many of the earlier tunnels were constructed on the former
-system, while of late years the latter method has been very largely
-adopted. The bottom heading may perhaps in some instances be more
-efficacious for drainage, but it is very liable to be frequently
-choked up when taking out the excavation to the full size, and the
-lower surface is much cut up by the movement and conveyance of
-materials. Another disadvantage arises from the necessity of removing
-such a large amount of the cutting approaching the tunnel entrance
-before a beginning can be made to the bottom heading. The top heading
-has the advantage that it requires less removal of open cutting
-previous to its commencement, and, being high up in position, there is
-less chance of its being stopped up by falling material, the finished
-excavations being carried out on the sides and below the heading.
-
-Where the headings are cut through solid rock, stiff shale, or compact
-chalk, little or no supports are necessary, but where they pass
-through clay or loose material, timbering will be required for sides,
-roof, and floor. Rough round poles, about 6 inches in diameter, are
-generally used for verticals, and are firmly secured to transverse
-sole-pieces, and on the top of these verticals strong transverse
-top-sills are fastened by means of rough tenons or checks. Strong
-boards are inserted at the back of this framework to keep the earth
-from falling into the working. The distance apart of the verticals
-will depend upon the description of material excavated; in very soft
-places they will have to be placed very close together, but where
-fairly sound and tenacious they may be placed at about 3-foot centres.
-The excavated material must be conveyed away to the entrance of the
-heading in small hand-trucks running on planks or light rails.
-
-The widening out of the excavation to the full size will be a
-repetition on a large scale of the work carried out in the heading,
-with the difference that, the exposed surfaces being of so much
-greater extent, extra care and precautions must be taken with the
-framework and shoring of the timbering.
-
-[Illustration: Fig. 202, 203]
-
-The form and arrangement of the timbering, as well as the number,
-sizes, and positions of the pieces, must be determined by the material
-of the excavation and the contour line of the finished arching or
-lining. The framework, which would be sufficient to support ordinary
-soft material, must be largely augmented both in quantity and scantling   172
-to meet the requirements for wet treacherous clay.
-
-Figs. 202 and 203 give end view and longitudinal section of timber
-framework frequently adopted for average tunnel work. The positions of
-the different pieces will explain themselves and the duty they have to
-perform. The main struts, or raking pieces, which have to sustain
-great pressure, may be shored against the finished lengths of masonry
-or brickwork. The timbering of the sides can be removed as the lining
-proceeds, but in many cases the round logs and boards near the crown
-cannot be withdrawn, and have to be left in the work, the space
-between the top of the arching and under side of the boards being
-firmly packed with brickwork, masonry, or dry rubble stonework.
-
-As the tunnel lining is generally carried forward in short lengths,
-following up the main excavations, the centering for the arching
-should be of such description that it can be readily transferred or
-moved forward as the work proceeds. The form of the centering, and the
-spacing of its upright supports, must admit of sufficient width for
-one or more lines of rails for the waggons required to remove the
-excavated _débris_ and convey the building materials used in the
-lining.
-
-Picks, bars, and shovels are the tools used in the excavation of the
-softer material and loose disintegrated rock, but for the hard rock,
-blasting will be necessary. The tunnel opening being comparatively
-small, only moderate blasting charges can be used with safety, and
-these must be placed so as to break up the rock-bed in a suitable
-manner for working, and without shaking or damaging the already
-completed excavation. Ordinary hand-drills, or _jumpers_, may be used
-for forming the charge holes, a number of them being at work at the
-same time, and the charges fired very closely one after the other. As
-the blasting operations necessitate the retiring of the miners to a
-considerable distance, out of the way of flying fragments, and the
-remaining away until the foul air has been dispelled, it is advisable
-to fire off several charges about the same time, and thus minimize as
-much as possible the stoppage to the drilling and clearing away the
-loosened material.
-
-[Illustration: Fig. 204, 205, 206, 207, 208, 209, 210, 211]
-
-Mechanical drills, worked by compressed air or other motive-power, are
-now very extensively used where the rock is solid and continuous. They
-are much more expeditious than the hand drills, but they are costly in    174
-their installation, and also in their working and maintenance.
-
-In some tunnels, where the material has been firm and dry, the upper
-portion of the excavation has been first removed, and the masonry and
-brickwork lining built in position down to about the springing of the
-arch, the remainder of the excavation being afterwards taken out, and
-the side walls built by means of shoring and underpinning.
-
-In other tunnels the complete section has been excavated and timbered,
-and the work of building commenced from the foundation of the side
-walls. A strong continuous invert from side wall to side wall is
-necessary where passing through soft swelling clay or loose strata
-intersected with small streams of water. Where the material is very
-solid and dry, it is not necessary to introduce inverts, but the
-foundations of the side walls should be laid at such a depth below
-rail-level as not to be affected by drain-water running through the
-tunnel.
-
-The side walls and arching may be either of masonry or brickwork, but
-should be of the best description, especially for the facework. For
-brick arching only the best hard-burnt bricks should be used, and the
-inner or exposed ring should consist of selected hard fire-bricks to
-withstand the heat and gases escaping from the funnels of the
-locomotives. The thickness of the side walls and arching will depend
-upon the description of material to be supported. In some places a
-comparative thin lining may be sufficient, while in others extra
-thickness must be given to resist the great pressure exerted by
-expanding clay and loose wet strata.
-
-Weeping-holes, or small drain-pipes, placed low down must be left in
-the side walls every three or four yards, or closer in very wet
-places, to allow the water collected at the back of the walls to
-escape into the side drains of tunnel. In building the arch portion
-every effort should be made to have close solid work without any open
-joints or spaces through which the water may run, and the crown of the
-arch and a few feet down on each side should be coated with cement or
-asphalte to lead all water away from the top to the sides. Water
-dripping from the under side of the arch on to the line is a great
-destructor of the permanent way materials, especially the fastenings;
-and bolts, nuts, fish-plates, and spikes placed in a wet dripping
-tunnel will not last half the time they would out in the open line,
-where they would have the sun and wind to dry them.
-
-[Illustration: Fig. 212, 213, 214, 215, 216, 217, 218, 219]
-
-Small arched recesses or niches should be formed in the side walls at     176
-convenient distances to serve as refuges for platelayers or others
-working in the tunnels.
-
-It is most essential that the space between the masonry and brickwork
-lining and the facework of the excavation should be carefully filled
-in and hard packed, so as to prevent the possibility of pieces of rock
-or other material falling on to the top of the arch. The neglect of
-this precaution may lead to a casualty years after the tunnel has been
-completed.
-
-It would be impossible to over-rate the importance of a constant
-faithful supervision of the building of the lining, especially the
-arching. The work has to be carried on by workmen in cramped
-positions, with imperfect light, and surrounded by all kinds of
-obstacles and inconveniences, and unless a detailed inspection be
-rigidly maintained, a carelessness in the selection of the materials,
-and a laxity in the workmanship, will be the inevitable result.
-
-Figs. 204 to 219 are sections of tunnels which have been constructed
-for double and single line railways. The sections give the normal form
-and dimensions adopted in each case, although there may have been many
-portions of the work where unfavourable or treacherous material
-necessitated an increase in the thickness of the side walls, or of the
-arching, or of both. The types vary in accordance with the opinions of
-the designers as to the most suitable section for the purpose, and
-range from the comparatively thin lining and vertical side walls shown
-on Fig. 207, to the almost circular form and very thick lining shown
-on Fig. 216. The latter is the section which experience has proved to
-be the best to sustain the enormous all-round pressure exerted by
-certain descriptions of swelling clay.
-
-Careful judgment will be required to decide which parts of a rock
-tunnel may be left unlined. The apparently solid-looking portions are
-oftentimes deceptive, and numbers of instances are on record of large
-pieces of rock falling down in tunnels which for many years had been
-considered as thoroughly secure. Where there is any doubt it is better
-and safer to put in a lining, even if only to the extent of an arching
-springing from side walls of solid rock, as shown on Fig. 206. A
-moderate additional expenditure at the time of construction may
-prevent a serious catastrophe afterwards.
-
-[Illustration: Fig. 220, 221, 222, 223]
-
-The faces or entrances to tunnels may be constructed with curved wing     178
-walls, as in Fig. 220, or with straight wing walls, as in Figs. 221,
-222, and 223. Where the approach cutting is in rock, the latter form
-is generally adopted.
-
-It would be misleading to put down any average price for tunnel-work.
-So much depends upon the locality, the description of material to be
-excavated, the cost of masonry or brickwork, and the cost of labour.
-Added to these come the unforeseen troubles of slips and water-laden
-strata, creating difficulties which baffle the miners for a time, and
-add enormously to the expenditure. Some tunnels for double line have
-been constructed in good ground, and under favourable circumstances as
-to building materials and labour, for as low as £32 per lineal yard;
-while others, carried out under adverse conditions, have cost as much
-as £150 per lineal yard. A medium somewhere between the two should
-represent the cost of tunnel-work through ground which does not
-present any special difficulty. At the same time it must be borne in
-mind that simple tunnelling which can be done in one locality for £50
-or £60 per lineal yard, would be increased 20, 30, or 40 per cent. in
-another, where building material for the lining is scarce and
-expensive.
-
-Tunnel-work abroad will generally cost more than the same work at
-home. The native labourers may perhaps be procured at low rates, but
-the skilled workmen must be brought from a distance, and will obtain
-high wages.
-
-Another form of tunnel-work, generally termed the covered-way system,
-is frequently adopted in towns and places where land and space are
-very valuable. This method consists in the excavating and removing of
-earthwork to admit of the building of the side walls and arching of a
-suitable tunnel-way, and then filling in over the top to a depth of
-three or four feet, or up to the level of the original surface of the
-ground. This work may be carried out by either removing the entire
-width of the earthwork before the commencement of any building
-operations, or by first forming two deep, well-shored trenches, in
-which to build the side walls up to about arch-springing. In bad
-ground the latter arrangement has the advantage, as the shoring and
-strutting to hold up the sliding material is limited to the widths of
-the two narrow trenches, and the centre block of earthwork is left
-untouched as a support to the strutting. When the side walls have been
-built sufficiently high the upper portion of the centre block of
-earthwork can be removed to allow of the erection of centering and        179
-building of the arching, and afterwards the remaining portion of
-earthwork can be removed at convenience. In this manner a tunnel-way
-may be constructed under streets, gardens, and even under buildings.
-Being nearly all done in the open, the work is more under control than
-in an ordinary tunnel, but it is usually very costly. Temporary or
-diverted roads must be arranged; the excavated material must generally
-all be removed by carts, sometimes to long distances; and provision
-must be made for diverting the network of sewers, gas, and water pipes
-which are intercepted along the route.
-
-Fig. 224 is a sketch of covered-way with brick arching. Fig. 225
-illustrates another type where cast-iron girders and jack-arches of
-brickwork were introduced on account of the small headway. In soft
-yielding clay it is necessary to construct strong inverts, as
-indicated in the sketches. Recesses for the platelayers should be
-provided every ten or fifteen yards.
-
-The above systems of covered-way were largely adopted in the
-construction of the underground portions of the Metropolitan Railway
-and District Railways in and around London.
-
-[Illustration: Fig. 224, 225, 226]
-
-In addition to the ordinary type of tunnel formed by first excavating
-the material and then lining the opening with brickwork or masonry,
-tunnels of moderate size have been constructed of cast-iron tubes,
-similar in section to Fig. 226. The tubes were cast in short segments,
-bolted together inside, the outer circumference, or surface in contact
-with the earth or clay, being left free from projections of any kind.
-By making the segments with bolt-holes exact to template, they were
-readily fitted together in the work, and a thin layer of suitable
-packing material placed between the bolting-flanges sufficed to render
-the tubes water-tight. The tunnelling was carried on by means of a
-short length of slightly larger tube, or cap, made of plate-iron or
-steel, which fitted over the leading end of the main tube. The front
-end of this cap was made very strong, and provided with doors through
-which the miners could work. A series of hydraulic presses attached to
-the cap were brought to bear on the bolting-flange of the last
-completed ring, and as the excavated matter was removed by the miners
-from the front the cap was forced forward by the hydraulic presses,
-and another ring of cast-iron segments inserted. On the City and South
-London Railway, constructed on the above system, the small annular
-space formed round the cast-iron tube by the operation of the sliding     181
-cap was filled in with cement grouting by means of an ingenious
-machine designed for the purpose.
-
-Large tunnels under rivers or tidal estuaries must each be dealt with
-according to the particular circumstances of depth below stream-bed,
-material to be cut through, length of tunnel, and gradient. The chief
-obstacle to be contended against in so much of the river tunnel-work
-is the large volume of water which pours into the workings through
-fissures in rock or seams of gravel and sand, necessitating the
-constant use of most powerful pumps. In ordinary land tunnels the
-gradients are generally laid out to fall towards one or both
-entrances, and any water finding its way into the excavations may be
-led away to the entrances by drains or pipes. On the other hand, in a
-river tunnel the gradients generally fall away from the entrances down
-towards the centre of the river, and all water coming in must be
-pumped out and raised up to at least the level of the river. In places
-where the water comes streaming in from many points, any failure or
-stoppage of the pumps would place the lives of the miners, and the
-security of the work itself, in great jeopardy. Iron shields, or
-protection chambers for the miners advancing the excavation, have been
-used with great success in carrying on work through loose wet strata
-which appeared to defy all other means of progress. Solid rock, chalk,
-or compact clay, may present no difficulty so far as they go, but a
-continued dip in the gradient, or a line of fault, may suddenly change
-the entire course of operations, and require the immediate use of the
-most powerful pumping machinery and protective appliances. The special
-features of each case will demand special precautions, and the
-judgment and inventive powers of the engineer will be severely tested
-in coping with the difficulties with which he is surrounded.
-
-
-
-
-  CHAPTER III.                                                            182
-
-  Permanent way--Rails--Sleepers--Fastenings--and Permanent way laying.
-
-
-Rails.--Accustomed as we now are to the substantial character of the
-permanent way of our railways, we can scarcely realize that in the
-earlier examples the rails or tram-plates were made of wood. The first
-lines of which we find any record were those constructed to facilitate
-the conveyance of coal, iron ore, stone, slate, or other heavy
-materials to shipping ports or points of distribution. Speed was a
-matter of little importance, the principal object being to introduce a
-distinct surface or roadway which would allow a heavier load to be
-hauled without increasing the hauling power. As a heavily loaded
-wheelbarrow, difficult to move on an ordinary road, can be readily
-wheeled along a wooden plank, so it may have been inferred that strong
-timber, laid in parallel lines and level and even on the upper
-surface, would form a track, or roadway, presenting far less
-resistance than the ordinary gravelled or paved roads.
-
-The wooden tramway was the first improvement over the ordinary road.
-The idea once originated, various types were soon introduced, and the
-sketch shown in Fig. 227 illustrates one which appears to have been
-early suggested and largely adopted. Wooden cross-sleepers, A, A,
-were placed at convenient spaces, and on the top of these strong
-timber planks or beams, B, B, were spiked at proper distances to
-suit the wheels of the waggons or four-wheel trucks, which had flat
-tyres like ordinary carts. The spaces between the sleepers were filled
-in with gravel or broken stone to form a roadway or hauling path for
-the horses. A little later _double rails_ were introduced, by placing
-a second or upper timber on the top of the lower one, as in Fig. 228.
-
-[Illustration: Fig. 227, 228, 229, 230, 231, 232, 233, 234, 235]
-
-This double rail arrangement not only strengthened the framework, but
-by increasing the height allowed a greater quantity of suitable           184
-material to be placed over the sleepers to protect them from wear by
-the horses’ feet. It can be easily understood that a wooden tramway
-could not be very durable. It would be affected by the sun, rain, and
-snow, and particles of sand and gravel thrown on to the tram beams
-from the hauling path would hasten the abrading or wearing away of the
-soft portions of the timber into hollows, leaving the hard knots
-standing out as projections. The uneven surface would produce a series
-of blows every time a loaded truck passed along, loosening the pieces
-and rendering the repairs constant and expensive. To obviate the rapid
-wear of the tram-timbers continuous narrow bars of wrought-iron were
-fastened on to the running-surfaces; these in a measure prolonged the
-life of the timbers, but at the same time added to the number of the
-pieces and fastenings to be maintained.
-
-Primitive as this description of road appears to be, it was in use for
-many years in some parts of the United States of America, and even
-after the introduction of the early locomotives; timber was abundant
-and cheap, and iron in any form was costly. These long thin strips of
-iron, placed as in Fig. 232, had a tendency to become unfastened at
-the ends, and to curl up in a very alarming manner, which earned for
-them the soubriquet of _snake heads_. Although iron was only used to a
-limited extent in the first instance, it was soon found to be a much
-more suitable material for a tram-path than the best timber. As a next
-progressive step we find that the tram-plates were made entirely of
-iron, of full width for the wheel-tyres, and with a guiding flange to
-keep the wheels on the proper track. In some cases the guiding flanges
-were placed inside the wheels, as in Figs. 229 and 230, and in others
-outside, as in Fig. 231. With the former plan a thicker covering of
-gravel or broken stones could be laid down to protect the sleepers
-under the horse-path.
-
-These solid tram-plates were made of cast-iron, that metal being
-considered the most convenient for manufacture and the least liable to
-suffer loss from rust and oxidization. Another advantage of the
-cast-iron was that broken tram-plates could be melted down and recast
-at a moderate cost.
-
-Long lengths of these cast-iron plate tramways were laid down in this
-country and abroad, and short portions of some of them remain in
-existence even to the present day. They were of immense service for       185
-the transportation of heavy materials, and without their adventitious
-aid many valuable collieries and quarries must long have remained idle
-and undeveloped. In thus providing a level, smooth, and comparatively
-durable wheel-track for the waggons, these tramways became the fitting
-pioneers of the great railway system which was to follow.
-
-Notwithstanding the great superiority of the cast-iron plates as
-compared with the former timber beams, much inconvenience was still
-caused by gravel and dirt falling on to the wheel-track and seriously
-impeding the haulage of the waggons. To overcome this difficulty the
-next step taken was to remove the guiding flange from the tram-plate
-and transfer it to the wheel, thus developing and introducing the
-original flanged wheel. This was a most important step, and paved the
-way for other improvements. The rails, or _edge rails_, as they were
-at first called, were made sufficiently high to allow ample space for
-the wheel-flanges to clear the ground, and were secured to cast-iron
-chairs placed on wooden cross-sleepers, or in some cases to stone
-blocks, as shown in Figs. 233, 234, and 235. The narrow top of rail,
-and its height above the horse-path, effectually prevented the
-lodgment of gravel or dirt, and the flanges on the wheels ensured a
-more even course. From the irregular and easily choked-up tram-plate,
-the system changed to the clean rail and properly defined track.
-Waggons could be hauled with greater freedom, and with less wear and
-tear to themselves and to the roadway.
-
-At this time the use of the steam-engine was becoming more general,
-and a fine field was opened out for its application as a motive-power
-on the tramways. Stationary engines, or _winding engines_, as they
-were called, were first employed to haul the trucks by means of long
-ropes passed round revolving drums, and supported at intervals by
-grooved pulleys placed between the rails at suitable distances. In
-this way fair loads could be conveyed, and at moderate cost; but the
-system was found to be only suitable for short distances, and it had
-the great drawback that horses or other motive-power were still
-necessary for sorting or distributing the trucks before and after
-their transit by rope haulage.
-
-The next great advance was to place the steam-engine on wheels, to
-enable it to haul and accompany the trucks. Crude and imperfect as the
-primitive locomotives must have been, a very short trial of them          186
-served to show that the rails of cast-iron then in use were totally
-unfitted to form a trackway for the newly invented machines. The short
-fish-bellied cast-iron rails were made in lengths merely to extend
-from chair to chair; they possessed little or no continuity, and from
-the inherent brittleness of the material they were constantly breaking
-and giving way under the increased weights imposed upon them. It
-became necessary to adopt a more reliable material, and attention was
-naturally turned to forged or wrought iron. The suggestion once made
-was promptly responded to by the iron makers. Special machinery was
-designed and constructed, and very soon wrought-iron rails were
-manufactured in large quantities. At first they were made very similar
-in section to the fish-belly cast-iron rails, but in lengths to extend
-over three or four sleepers. The increased length gave greater
-stability to the road, and permitted an increase of speed. The
-manifest superiority of the wrought-iron rails led to their universal
-adoption, and a great impetus was thus given to their manufacture.
-Improvements were made in the machinery for rolling, and more care was
-bestowed in the working of the iron. Changes were made in the section
-of the rails; the fish-belly form was discarded, and a double-head
-type was introduced to give more lateral stiffness. At this period in
-its history the capabilities of the _iron road_ began to be more fully
-recognized, and the supporters of the system foresaw a great future
-success, both for the conveyance of passengers as well as goods.
-Hitherto the tramroads or railroads had been used for minerals and
-merchandize only, but it was now claimed that on a carefully
-constructed line, and with improved locomotives and rolling-stock, it
-would be possible to convey passengers more conveniently and rapidly
-than by any other method.
-
-[Illustration: Fig. 236, 237, 238, 239, 240, 241, 242, 243, 244, 245,
-246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257, 258]
-
-Inventive minds were at work to accomplish so desirable an object, and
-public enterprise was forthcoming to provide funds for the purpose.
-The successful working of the first passenger line formed the dawn of
-a new era in travelling, and similar lines were soon projected for
-other places. The wrought-iron rails in use at this time were
-generally of a double head form, and rarely exceeded 12 or 15 feet in
-length. They were held by wooden pegs in cast-iron chairs, which were
-secured to timber cross-sleepers or stone blocks, as shown in Figs.       188
-234 and 235.
-
-They were light in section, and it is stated that the first rails on
-the Liverpool and Manchester Railway weighed only 33 lbs. per yard.
-
-The railway system spread rapidly, and the constantly increasing
-traffic of all kinds soon necessitated heavier rails. Various sections
-were devised and tried on different lines, one of the main objects in
-view being to obtain a steady road for the increasing speeds, as well
-as one of durability. Some of these sections are shown in Figs. 236 to
-258.
-
-Sections 236 to 248 all required chairs to attach them to the
-sleepers. The flange rails, 249 to 253, and bridge rails, 254 to 256,
-also rail 257, were designed to rest direct upon the sleepers without
-the necessity of chairs; and the Barlow rail, 258, with its great
-width of 11 or 12 inches, was intended to be used without sleepers of
-any kind, the gauge being secured by means of angle iron tie-bars.
-
-Rails were rolled heavier and longer, and more care was bestowed on
-the fastenings; but, notwithstanding these improvements, the
-rail-joints still continued to be the weak point in the road. Even
-with an extra large joint-chair and stout wooden key, there was much
-vertical play at the ends of the rails, producing objectionable noise
-and vibration in the running, and acting detrimentally on all the
-fastenings. The introduction of fish-plates at the rail-joints, as
-shown in Fig. 259, effected an improvement which cannot be overrated,
-as by their adoption such security, speed, and smoothness became
-attainable as were not before possible. With a pair of simple rolled
-wrought-iron fish-plates, or splices, and four bolts--two through the
-end of each rail--a better, smoother, and more effectual joint was
-obtained than had ever been produced by the heavy cast-iron
-joint-chairs. The system of fishing, or splicing, was at once admitted
-to be the simplest and most direct method of joining the rails; and,
-although minor detailed improvements have since been made, the
-arrangement, as a principle, has never been superseded. Many miles of
-fished rails were laid down with a chair, or support, placed
-immediately under the joint, forming the method termed the supported
-fish-joint; but experience proved that this mode of application did
-not give such a good result as the suspended fish-joint, and the
-latter plan has now been adopted on almost all railways.
-
-[Illustration: Fig. 259, 260, 261, 262, 263, 264, 265, 266, 267, 268,
-269, 270, 271, 272]
-
-The experience obtained year after year in the wear of rails under        190
-heavy traffic, led to continued improvements both in the method of
-rolling and in the selection of the iron to form the rail-pile; one
-description of iron was found more suitable for the head, or running
-surface, and another for the vertical web; but, even with the best
-machinery and most carefully assorted materials, high-class
-wrought-iron rails were liable to lamination, and long thin strips of
-iron became detached from the upper, or wearing, surface. The rail was
-composed of many layers of iron, and it was not always possible to
-ensure that they were all thoroughly welded, or incorporated together.
-As early as 1854 a few experimental solid steel rails were laid down
-on some of the principal railways, and gave excellent results as to
-evenness of wear and durability, but their cost of manufacture
-rendered their extended use almost prohibitory.
-
-Compound rails of steel and wrought-iron, as in Fig. 260, were also
-tried on several railways, but the practical results were not such as
-to lead to a very extended adoption. In preparing the _pile_ for a
-compound rail, suitable wrought-iron bars were placed to form the
-lower member or flange, the web, and part of the head, and a slab of
-steel was placed on the top to form the upper portion of head, or
-wearing surface of the rail. It was intended that in the process of
-rolling these distinct layers were to be incorporated together, to
-form the section shown in Fig. 260. Doubtless many good wearing rails
-were manufactured on this system, but the inherent difference of the
-two materials, steel and iron, rendered it very difficult to ensure
-such uniform incorporation as would withstand the constant pounding
-under heavy, fast traffic. It was not until some years later that the
-process of the Bessemer Converter was discovered and perfected, by
-means of which steel can be produced in large quantities far more
-rapidly and at much less cost than by any other method hitherto
-adopted. The introduction of this process for making steel caused a
-complete revolution in the material for rails. Steel which had
-previously been excluded on account of its cost, could now be supplied
-at a moderate price, and, from its compact and homogeneous character,
-promised a very much longer wearing life than the best wrought-iron
-rails that had ever been rolled. Experience has shown that these
-promises have been fully verified; wrought-iron rails are things of
-the past, steel rails have taken their place, and can now be purchased    191
-at a less price per ton than the iron rails of twenty years ago.
-
-It is interesting to note that out of the many varied sections that
-have been designed, some of which are shown in the sketches described,
-only two have practically survived--the bullhead rail and the flange
-rail. The bull-head rail, Fig. 261, has grown out of the original
-double-head rail, which had both the top and bottom members made to
-the same section and weight, with the object that, when the upper
-table had become so much worn as to be unfit for further use, then the
-rail could be turned, and the other table, or head, brought into
-service. Experience, however, proved that turned rails formed a most
-uneven and unsatisfactory road, the long contact with the cast-iron
-chairs resulted in serious indentations at the rail-seats, rendering
-the rails totally unfitted for smooth running. In practice, therefore,
-it has been found better to restrict the running wear to one head
-only, and to give increased sectional area to that head, and, at the
-same time to diminish the sectional area of the lower member to a
-corresponding extent, but to retain the same width, so as to obtain a
-full bearing surface on the cast-iron chair. Steel bull-head rails are
-now adopted on nearly all the principal lines at home, and on several
-of the leading lines abroad.
-
-The flange rail, Fig. 265, was designed to give a broad, direct
-bearing on the sleepers, and thus avoid the necessity of using chairs.
-Rails of this section have been laid down on many of our lines at
-home, and are very largely used on the Continent, in the United States
-of America, and in our colonies generally. This section is, also,
-nearly always adopted for narrow-gauge railways. Having fewer parts,
-it makes a cheaper road than the bull-head rail, but is not considered
-so strong or suitable for heavy and fast traffic. Comparing the two
-rails shown in Figs. 261 and 265, each having exactly the same size
-and sectional area in the head, it will be seen that there is more
-material in the lower member, or flange, of the one rail than there is
-in the lower member of the other; the weight per lineal yard being 79
-lbs. for the former and 75 lbs. for the latter. But this small excess
-in the weight and cost of the flange rail falls very short of the cost
-of the cast-iron chairs and wooden keys necessary for the bull-head
-rail.
-
-Up to the years 1870-1875, it was the common practice to make the top,
-or wearing surface of the rail, comparatively round, as shown on the      192
-typical sections, Figs. 263 and 267. The effect of this sharp-curved
-outline was to limit the first wearing, or contact surface to a narrow
-strip along the head of rail, causing a tendency to groove or form
-hollows in the treads of the wheel-tyres. As the rail wore down, the
-upper surface assumed a much flatter curve, more closely assimilated
-to the section of the wheel-tyre, and giving better results for
-regular wear under heavy traffic. Profiting by this experience, the
-rails of the present day are made much flatter on the head than they
-were formerly, as will be noted from the sections shown on Figs. 261,
-266, and 269, which represent types of rails now actually in use on
-some of the principal railways.
-
-In designing a rail for any given line, the section and weight of the
-rail must necessarily be influenced by the weight of the rolling-stock
-passing over it, and the amount of the traffic it has to sustain.
-
-The engine, being the heaviest vehicle in the train, will give the
-measure of the greatest weight on one pair of wheels. Engines vary
-considerably on different lines, ranging from ten tons to eighteen
-tons or more on one pair of driving-wheels, according to the
-description of work to be performed.
-
-Very often secondary or branch lines, with comparatively light
-traffic, have steep gradients, necessitating engines as heavy as on a
-main trunk line; but the number of trains on the former may not exceed
-twenty per day, while on the latter they may amount to one hundred and
-fifty or two hundred. It is evident that the rail which would last for
-very many years under the small traffic, would have a very short life
-under the frequent traffic. Hence the reason why it is found expedient
-to give a large increase of material in the heads of rails carrying
-the heavy, constant train service of many of our main lines.
-
-Figs. 261, 262, and 263 are sections of rails in use on lines having
-heavy engines and fast trains, but with a comparatively small daily
-train service, and Figs. 264, 266, 267, and 268 are sections of rails
-carrying the heavy, fast, and incessant traffic of some of our leading
-lines.
-
-On lines having small traffic, slow speeds, easy gradients, and
-comparatively light engines, a reduced section of rail may be adopted;
-but in doing so it is well to allow for any probable future
-development of traffic which might cause the introduction of heavier
-engines.
-
-Figs. 269 to 272 show sections of rails varying from 72 to 60 lbs. per    193
-yard, also a section of a 45-lb. steel flange-rail, much used on
-3-foot narrow-gauge railways.
-
-Valuable and interesting statistics have from time to time been
-recorded, with a view to ascertain the average life of a steel rail,
-by obtaining the number of million tons of train load which it would
-sustain before it became worn down to such an extent as to be no
-longer of service on the line. It will be readily understood that the
-rate of wear of a steel rail will depend not only on the weight and
-section of the rail itself, but on the class of rolling-stock, and the
-description of traffic it has to carry. It will also be largely
-affected by the circumstances of whether the line is on a level or on
-an incline.
-
-The writer has had careful measurement taken of the wear of the steel
-flange-rail (Fig. 265), 79 lbs. per yard, and the result shows that
-with a traffic not exceeding twenty-four goods and passenger trains
-per day, one-tenth of an inch was worn off the top of the rail in ten
-years on the comparatively level portions of the line; but that the
-same amount of one-tenth of an inch was worn off in six years by the
-same traffic, on the same district of the line, in places where the
-gradients varied from 1 in 100 to 1 in 70. The heavy pounding of the
-engines, and the working of the brakes tend very materially to shorten
-the life of the rails on the inclines.
-
-As now made, the steel rails manufactured under the converter process
-exhibit great similarity in the analysis of their component parts; at
-the same time it is well known that a slight preponderance or
-reduction of one or more of the constituents will result in making the
-steel hard or soft. The following statement gives the analysis of
-twelve steel rails, six of which were classed as _hard_ steel, and six
-as _soft_ steel:--
-
-  HARD STEEL.--ANALYSIS OF SIX STEEL RAILS WHICH BROKE EITHER IN
-               TESTING OR IN LINE.
-
-  -----------+--------+--------+--------+--------+---------+---------
-             |    1.  |    2.  |    3.  |    4.  |    5.   |    6.
-  -----------+--------+--------+--------+--------+---------+---------
-  Carbon     |   0·47 |   0·51 |   0·56 |   0·43 |   0·47  |   0·54
-  Silicon    |   0·09 |   0·08 |   0·08 |   0·09 |   0·095 |   0·121
-  Sulphur    |   0·06 |   0·06 |   0·06 |   0·06 |   0·054 |   0·056
-  Phosphorus |   0·07 |   0·06 |   0·06 |   0·08 |   0·08  |   0·057
-  Manganese  |   1·23 |   1·10 |   0·90 |   1·23 |   1·15  |   1·26
-  Iron       |  98·08 |  98·19 |  98·34 |  98·11 |  98·151 |  97·966
-             +--------+--------+--------+--------+---------+---------
-             | 100·00 | 100·00 | 100·00 | 100·00 | 100·000 | 100·000
-  -----------+--------+--------+--------+--------+---------+---------
-
-  SOFT STEEL.--ANALYSIS OF SIX STEEL RAILS WHICH STOOD THE TEST WELL,     194
-               AND BENT FREELY WITHOUT SHOWING ANY SIGN OF FRACTURE.
-
-  -----------+---------+---------+---------+---------+---------+---------
-             |    1.   |    2.   |    3.   |    4.   |    5.   |    6.
-  -----------+---------+---------+---------+---------+---------+---------
-  Carbon     |   0·35  |   0·39  |   0·37  |   0·34  |   0·35  |   0·250
-  Silicon    |   0·06  |   0·07  |   0·07  |   0·08  |   0·07  |   0·069
-  Sulphur    |   0·062 |   0·061 |   0·062 |   0·061 |   0·061 |   0·046
-  Phosphorus |   0·061 |   0·061 |   0·061 |   0·063 |   0·062 |   0·058
-  Manganese  |   0·870 |   0·875 |   0·866 |   0·864 |   0·800 |   0·636
-  Iron       |  98·597 |  98·543 |  98·571 |  98·592 |  98·657 |  98·941
-  -----------+---------+---------+---------+---------+---------+---------
-             | 100·000 | 100·000 | 100·009 | 100·000 | 100·000 | 100·000
-  -----------+---------+---------+---------+---------+---------+---------
-
-Many rails which have been broken in the line under traffic have been
-analyzed, and proved to be hard steel; while others, which have been
-bent into all sorts of shapes, but not broken during accidents or
-derailments, have also been tested, and proved to be of soft steel.
-
-Some engineers are advocates for a hard steel rail, and claim for it
-greater durability and longer wear; but even supposing such hard rail
-should possess a slight superiority over the soft rail, it is well to
-consider whether such assumed advantage is not obtained at the risk of
-incurring greater liability to fracture. It must be borne in mind that
-a rail, once placed in the road, is exposed to all the changes of
-temperature from heat to frost, and has frequently to sustain
-increased strains arising from loose sleepers, where the gravel or
-ballast has been disturbed during heavy rains.
-
-When writing a specification for steel rails, it is usual to state the
-number of tons per square inch in tensile strain which the steel must
-be able to sustain without fracture, and also to stipulate that some
-of the rails will be tested by the falling-weight test. In the latter
-test a rail is placed, say at 3 feet bearings, and in a similar
-position to what it would occupy in the road, and a weight of eighteen
-hundredweight, or one ton or more, according to section of rail, is
-allowed to fall from a height of 9 or 10 feet, on to the rail, at the
-centre between the bearings. With three blows from the given height,
-the rail must not bend or deflect more than a specified amount. The
-falling-weight test is, perhaps, rather a rough and ready one; but it
-is always reassuring to prove that the rails will withstand such a
-severe ordeal, as it must be a very exceptional circumstance in the
-routine of railway working which will produce a blow or shock equal       195
-in effect to the falling-weight test. The rails form such an important
-part of the trackway, almost the very basis on which the traffic has
-to depend for its safety, that, apart from the question of wear, no
-effort should be spared to ensure their thorough soundness and
-efficiency.
-
-In modern practice rails are generally used in lengths varying from 25
-feet to 30 feet. There is no difficulty in making them longer; but any
-excess over the above lengths is found to be inconvenient for
-transport, for handling in the line, and for making the necessary
-allowance for contraction and expansion at the joints. Steel rails are
-generally marked on the vertical web with the initials of the railway
-company, the name of the manufacturer, and the year in which they are
-rolled. This is done by cutting out the letters in the last pair of
-rolls through which the rails have to pass before they are completed,
-so that on the rails themselves the letters stand out in raised
-characters, thus: G.N.R.I.......C. CAMMELL & C^o 1896. In this
-manner the rails always carry for reference the name of maker and
-date.
-
-When comparing the relative merits of the flange-rail and
-bull-head-rail permanent way, the question of strength and durability
-must be considered, as well as that of economy. The flange-rail road
-has undoubtedly fewer parts and fastenings, and when the flange is
-wide, the sleepers sound, and the rail securely held down to the
-sleepers, the result is a smooth running road. So long as the rail can
-be maintained in a constant close contact with the wooden sleeper, the
-running is almost noiseless, the jarring on the rails being absorbed
-or taken off by the timber; but so soon as a little space or play
-takes place between the spikes or other fastenings and the upper
-surface of the flange, the rail obtains a certain amount of rise, or
-lift, which comes into action upon the passing of every rolling load,
-producing unsteadiness in the rail and a clattering noise in the
-running. A flange of 5 inches, on a sleeper 10 inches wide, has a
-bearing surface of 50 square inches (assuming the sleeper to be square
-cut, without any wane on the edges), and this area of 50 inches is
-only about half of the bearing surface on the sleeper of an ordinary
-modern cast-iron chair.
-
-Main-line locomotives have weights on the driving-wheels varying from
-16 to 18 and 20 tons. Taking 18 tons as representing a common practice
-for a large express engine, would give 9 tons as the weight imposed on    196
-each rail by each driving-wheel Assuming this weight to be distributed
-over three sleepers would give a dead weight of 3 tons per sleeper, or
-134 lbs. on every square inch of the 50 square inches of surface, or
-rail-bearing area, on each sleeper, without taking into account the
-effect of the blow or percussion from the rolling load. The presence
-of a loose sleeper throws additional weight on the adjoining sleepers,
-and increases the destructive influence on the timber. The constant
-application of heavy rolling loads on a small bearing area of timber
-crushes and wears away the timber very rapidly. The small bearing
-surface of the flange rail expedites the cutting down into the
-sleeper, and as the rail beds itself further and further into the
-wood, the fastenings must be driven or screwed down to follow the
-flange. Spikes may be driven down, but the further they go they have a
-less thickness of timber for a bed, and therefore a diminished hold.
-Crab bolts are apt to become rusted or ironbound, so that they cannot
-be screwed further, and must then be taken out and replaced with new
-ones. The narrower the flange, the more rapidly does the rail-seat cut
-down to a thickness inconsistent with safety. The sharp edge of the
-flange-rail has a tendency to cut a channel in the spike, and it is
-not at all an unusual occurrence to find strong square shanked
-dog-spikes, which have been thus cut into to the extent of a third or
-even half their thickness. The comparative narrow flange places the
-spikes at great disadvantage in point of leverage for holding down,
-and this weakness is soon made manifest, particularly on curves, where
-additional crab bolts or other devices are rendered necessary to
-counteract the tendency of the rail to rock and tilt over sideways.
-When the head of the rail cannot be kept in its proper position, the
-gauge becomes widened, and an irregular sinuous motion takes place in
-the running of the train. This drawback has been found to be a serious
-matter where light narrow flange rails have been adopted to carry
-comparatively heavy, short wheel-base engines. In some cases
-wrought-iron sole-plates, or even cast-iron bracket-chairs, have been
-introduced to give more bearing surface on the sleeper and increased
-support to the rail, but neither of the two methods give the same
-simple complete hold to the rail that is obtained by the cast-iron
-chair for the bull-head rail.
-
-On the other hand, the modern cast-iron chair for the bull-head rail      197
-has at least double the bearing surface on the sleeper to that of the
-flange-rail seat, so that under the same circumstances of rolling load
-as above described, the weight of 134 lbs. per square inch would be
-reduced to half, or 67 lbs. The greater length given to the chair
-effectually prevents any rocking action on the part of the rail, and
-reduces to a minimum any lifting action on the spike. A good fitting
-chair--especially when keyed on the inside--provides a most effectual
-support to the rail both vertically and laterally, and maintains the
-rail to accurate gauge. By giving proper clearance space at the tops
-of the chair-jaws, a bull-head rail can be taken out by simply driving
-out the wooden keys, and a new rail inserted without in any way
-disturbing the chairs or spikes. To change a flange rail necessitates
-the slackening and removal of a large number of the spikes and crab
-bolts.
-
-As the sleepers under the chair road suffer less from the crushing of
-the timber, they have a much longer life in the line, and remain
-serviceable until they are incapacitated from decay. This is a very
-important item in places where timber sleepers are expensive. The
-steadiness of the chair prolongs the efficiency of the spikes.
-
-As the actual wearing portion of the rail is the head, or wheel
-contact surface, a liberal area--consistent with the expected
-traffic--must be given to that part, whether for a bull-head rail or a
-flange rail. By comparing the two sections, Figs. 273 and 274, the one
-for an 85-lb. bull-head rail, and the other for a 100-lb. flange rail,
-it will be seen from the dotted lines that the heads of each rail are
-almost identical, the difference of 15 lbs. being disposed of in the
-flange of the heavier rail. Practically, therefore, we have 15 lbs.
-per yard extra weight of steel in the rail, on the one hand, as
-against the cast-iron chairs and steadier permanent way on the other.
-
-For lines where the traffic is small, weights light, speeds low, and
-economy of construction imperative, the flange-rail permanent way will
-be very suitable.
-
-The writer has had long mileages of each description of permanent way
-under his charge, both at home and abroad, for many years, and the
-result of his experience has shown that, although a fairly good road
-may be made with flange rails, still, for constant, heavy, fast
-traffic, the bull-head rail with cast-iron chairs makes a much
-stronger, more durable, and better permanent way than any flange
-railroad.
-
-[Illustration: Fig. 273, 274]
-
-Briefly summarized, the principal advantages and disadvantages of the     199
-two kinds of rails stand as follows:--
-
-                            ADVANTAGES.
-
-        Bull-head Rail.                        Flange Rail.
-
-  Large bearing surface of chair       Fewness of parts, and less
-  upon the sleeper, and greater        cost.
-  stability of the rail.
-                                       Smaller quantity of ballast
-  Longer life of wooden sleeper.       required to cover up the foot
-                                       of rail.
-  Impossibility of rail tilting
-  over outwards.                       More lateral stiffness than
-                                       the bull-head rail.
-  Facility for changing a rail
-  without disturbing the
-  fastenings in the sleepers.
-
-  Easier to maintain, owing to
-  less disturbing strains on the
-  fastenings.
-
-  A bull-head rail is more
-  readily set or laid to follow
-  line of curve.
-
-  In most cases the one set of
-  chairs will serve for a second
-  set of rails.
-
-  Perfect straightness of rail:
-  it is very rare to find a
-  crooked bull-head rail.
-
-  Easier to roll, and more
-  likely to obtain uniformity of
-  steel.
-
-                           DISADVANTAGES.
-
-        Bull-head Rail.                        Flange Rail.
-
-  Bull-head Rail.                      The small rail-seat area on
-                                       sleeper throws great crushing
-  Greater cost.                        weight on the timber.
-
-  More ballast required to cover       Shorter life of wooden
-  up the rail.                         sleepers from the cutting down
-                                       of rail-seats.
-  Less lateral stiffness than
-  the flange rail.                     The edge of flange cuts the
-                                       spikes after a few years.
-
-                                       The undulation of the rail
-                                       under trains tends to raise
-                                       the spikes, and causes lateral
-                                       movement in the rails.
-
-                                       More difficult to maintain, in
-                                       consequence of greater
-                                       tendency of the fastenings to
-                                       work loose.
-
-                                       Difficulty in getting flange
-                                       rails straightened laterally.
-
-                                       More difficult to set to
-                                       follow regular line of curves.
-
-                                       More difficult to roll, and
-                                       less likely to obtain
-                                       uniformity of steel.
-
-
-Tramway Rails.--Tramways on streets or public roads are now
-universally recognized as important branches of the railway principle.
-Their smoothness of movement, increased accommodation, and many other
-advantages as compared with the old road omnibus, render it no longer
-necessary to call for special advocacy when there is a possibility of
-their introduction. They occupy a position so thoroughly appreciated      200
-by the public that any check on their reasonable use or extension
-would be considered as detrimental to the interests of the travelling
-community.
-
-As a rule, these tramways are laid down on streets or roads previously
-constructed for the ordinary road traffic, where all the preliminary
-work of earth filling, bridges, drainage, etc., has already been
-accomplished, and there only remains the selection and laying down of
-the rails or permanent way over which the tram-cars will have to run.
-The description and weight of permanent way to be adopted will depend
-largely upon the weight of the cars to be used and the system of
-motive-power decided upon for the haulage--whether horses, steam,
-cable, or electricity.
-
-As the portion of the streets or public roads along which the tramway
-has to be laid will, in all probability, have to be occupied and
-traversed by all kinds of vehicles besides the tram-cars, it is
-absolutely necessary that the permanent way for the tramway should be
-of such description as to require the least possible amount of
-adjustment of fastenings or opening out of the roadway for repairs.
-Where the entire width of the street, including the space between the
-tram-rails, is paved with stone setts, the opening out of even a short
-length for repairs is tedious and costly, and causes considerable
-obstruction to the street traffic. It is most important, therefore,
-that the rail and its fastenings should not only be strong enough for
-its own tram service and the carts and drays which will pass over and
-across the track in all directions, but it must possess the minimum
-necessity for disturbance.
-
-Figs. 275 to 279 are sketches of a few of the many types which have
-been brought into use in various places.
-
-Where the public roads are wide, and a space can be set apart at the
-side for the special use of the tramway, the arrangement shown in Fig.
-275 will be simple and efficient. It is very similar to an ordinary
-railway permanent way with the ballast filled in flush with the top of
-the rails. The rails are shown as flange or flat-bottom rails, fished
-together at the joints, and properly secured to transverse sleepers of
-wood, iron, or steel. The space between and outside the rails is
-filled in with small-sized broken stone ballast or good clean gravel,
-and forms an even surface, over which animals or cattle may pass
-without risk of being thrown down.
-
-[Illustration: Fig. 275, 276, 277, 278, 279]
-
-Fig. 276 represents a system which was laid down extensively, especially  202
-for horse tramways, but not proving efficient, has been superseded by
-other types of a stronger and more durable description. The rail was
-rolled with a continuous groove to provide clearance for the flanges
-of the car-wheels, and the sides of the rail were turned down so as to
-fit over the longitudinal timber sleeper, to which the rail was
-secured by staple-dogs, as shown. Cast-iron chairs, spiked on to
-wooden cross-sleepers, held the longitudinal sleepers in position. The
-wooden sleepers were favourable for smooth running, but the section of
-the rail, practically a light channel-iron laid on the flat, was most
-unsuitable for carrying weight or for making a proper joint.
-Experience proved this road to be very difficult to maintain in good
-order for easy traction. The staple-dogs worked loose after a little
-time, and the rail, having scarcely any vertical stiffness, rose and
-fell during the passage of every car-wheel, resulting in most uneven
-joints and a clattering roadway.
-
-With the view to obtain a stronger and more permanent support for the
-rail than the longitudinal timber sleeper last described, various
-forms of cast-iron chairs were devised. Fig. 277 represents one of
-these patterns. The rail, which is of T-section with a
-continuous wheel-flange groove, is secured to the cast-iron chair by
-the cross-pin, as shown. Although this cross-pin may in time work a
-little loose, it cannot work out, being kept in position by the
-paving-setts on each side. The cast-iron chairs are placed at
-convenient distances, and being set in a bed of concrete, do not
-require cross-sleepers or tie-bars. This type makes a strong road, but
-the rail-joints cannot be made so even or efficient as with the more
-modern form of rail.
-
-Rail manufacturers are now able to roll a section of rail combining
-the vertical stiffness of the ordinary flange, or flat-bottom, rail
-with the running-head and continuous wheel-flange groove, considered
-the most suitable for heavy tramway traffic. The introduction of this
-section of rail has contributed greatly to the increased efficiency
-and durability of the permanent way for street traffic; and as the
-ends of the rails can be secured by ordinary fish-plates, there is the
-great acquisition of even joints and increased smoothness in the
-running of the tramcars. This rail can be rolled of various weights to
-suit the rolling loads. On some tram-lines a moderately heavy section
-has been adopted, and secured to transverse sleepers of rolled iron or
-steel laid on a bed of concrete. On others similar rolled metal
-sleepers have been used, but laid longitudinally. For some descriptions   203
-of traffic a much heavier section of rail has been used, having a base
-sufficiently wide to provide ample bearing on a bed of concrete
-without the intervention of either transverse or longitudinal
-sleepers.
-
-Fig. 278 is a sketch of the modern rail as laid down on a rolled steel
-transverse sleeper, the rail being held in position either by
-turned-up clips, wedges, bolts, or any of the devices in use for
-similar duty in the rolled-steel sleepers for ordinary railway
-permanent way.
-
-Fig. 279 shows a modern rail of a heavier section, with a wide flange
-resting direct on a continuous bed of concrete. The gauge is
-maintained by bar-iron tie-bars placed vertically so as to fit in
-between the courses of the paving-setts, the ends being forged and
-screwed to pass through holes in the vertical web of rail, and secured
-in position by nuts. Both in this, and in type Fig. 278, ordinary
-fish-plates are adopted at the rail-joints, as indicated by dotted
-lines.
-
-In the last two examples above described all the materials are of the
-most durable description, and the least liable to wear or decay, but
-it will be necessary to guard against making the fastenings and the
-bars too light for the duty they have to perform. There should be
-ample material in the head of the rail to allow of a fair wearing
-down, and the continuous flange groove should be sufficiently deep to
-meet this wearing away without causing the wheel-flanges to strike the
-bottom of the groove.
-
-[Illustration: Fig. 280, 281, 282, 283, 284, 285, 286, 287, 288, 289,
-290, 291]
-
-
-Fish-plates.--In the first examples of the newly invented
-wrought-iron fish-plates they were made to the depth to fit in between
-the upper and lower tables of the rail, as shown in Fig. 280, a small
-space or clearance being left between the inner sides and the vertical
-web of the rail. Ordinary nuts and bolts were used in most cases, but
-in some instances one of the fish-plates was tapped, as in Fig. 281,
-forming one long continuous nut, and in others both fish-plates were
-tapped, as in Fig. 282, and right and left handed bolts were used.
-Neither of the two arrangements of tapped fish-plates proved
-sufficiently successful as to lead to their general adoption. When the
-bolts became rusted in, or iron-bound, it was found to be almost
-impossible to remove them without permanently damaging the
-fish-plates. With the four right and left handed bolts the operation
-of tightening, or removing, the fish-plates was very tedious, as each
-bolt had to be turned a very little at a time, one after the other.       205
-Independent bolts and nuts, either of iron or steel, are now
-universally used; plain holes, with sufficient allowance for work and
-expansion, being punched or drilled in the rails and fish-plates.
-
-For many years the depth of the fish-plates continued to be made the
-same as the space between the upper and lower members of the rail, as
-shown in Fig. 280; but with the heavier loads and higher speeds of our
-modern railway working it has been found necessary to strengthen the
-joints by providing deeper or stiffer fish-plates, as shown in Figs.
-283, 284, and 285. For bull-head rails the fish-plates have been
-brought down underneath the lower table, and in some cases extended
-down sufficiently far to admit of a second set of fish-bolts under the
-rail. For flange rails some fish-plates are used simply of the form of
-angle irons, and others have the angle portion carried out beyond the
-end of the flange, or foot of rail, and then turned down vertically to
-a depth of an inch or more below the rail. The latter makes a very
-strong fish-plate.
-
-Fish-plates, like rails, are now almost universally made of steel.
-
-The efficiency and durability of a fish-plate depends materially upon
-its angle of contact with the under side of the head of the rail, and
-the extent of its contact surface. It would be an error to suppose
-there is little or no wearing away in fish-plates, as in reality there
-is very considerable wear, and especially in rails of lighter section.
-If the under side of the head of rail has a curved outline, as in the
-rail in Fig. 287, there will be some difficulty in ensuring a perfect
-fit in the fish-plates; the curve of the one may not quite correspond
-to the curve of the other, and the contact surface will be very small.
-It is better to make these contact surfaces in straight lines, and to
-a wide angle rather than to an acute angle. In Fig. 288 the under side
-of head and corresponding top of fish-plates are set at an acute
-angle, and fish-plates to this pattern will soon wear up to the
-vertical web of rail, and cause a loose noisy joint.
-
-In Fig. 284, showing a different type of rail, the contact surfaces
-are set at a very much wider angle, and will allow much more wear
-before the fish-plates can work close up to the web of the rail.
-
-When once the fish-plates are close up to the web, the best and           206
-tightest bolts cannot prevent the vertical play in the ends of the
-rails.
-
-A hammering sound will announce each successive drop of the wheels
-from one rail to the other, more distinctly, perhaps, at slow speeds
-than when travelling quickly, but existing equally under both
-conditions. The unpleasant jarring sensation is annoying to the
-passengers, and has a straining, loosening effect on all the bolts and
-fastenings. Unless the fish-plates have a thorough continuous bearing
-against the upper and lower shoulders of both the rails, it will be
-impossible to obtain a smooth even joint. A road may have good rails,
-good chairs, and good sleepers, but if the fish-plates are worn and
-loose the entire permanent way may be pronounced faulty, and all on
-account of a minor defect which can be easily remedied. With strong,
-properly fitting fish-plates, the position of the joints should be
-imperceptible when passing over them in a train.
-
-The writer has had many miles of line where the fish-plates have worn
-hard up to the rail web. In cases where the rails were good, with the
-prospect of a long life, new fish-plates of suitable section have been
-provided. In others, thin wrought-iron plate liners, 1/16 or 1/12 of
-an inch thick, have been inserted, as in Fig. 291, so as to bring the
-plates well out from the web, and allow the fish-bolts and fish-plates
-to exercise the free gripping action which is absolutely necessary to
-prevent the vertical rising and falling of the rail-ends during the
-passage of a rolling load. Fish-plate liners of the above description
-have given excellent results, and have restored the efficiency of the
-fish-plates for several years.
-
-
-Chairs.--All rails which partake of the double head section, or have
-a base not wider than the head, require supports or carriers to attach
-them to the sleepers, and to secure them in their proper upright
-position. In the days of the original _edge rails_, at the
-commencement of the railway era, these supports were very
-appropriately termed _chairs_, and this name has now been adopted in
-all parts of the world. Cast-iron is the most suitable material for
-railways chairs, being much cheaper in cost and less liable to loss or
-deterioration from rust than wrought-iron. Cast-iron chairs can be
-formed to suit any section of rail, and from the nature of the
-material they cannot be bent or twisted out of shape so as to
-interfere with the gauge or cant. They may break during an accident or
-derailment, but the fracture can be detected at once, and the broken      207
-chair quickly replaced.
-
-The chair performs the very important duty of distributing the weight
-of the rolling load on the upper surface of the sleeper. If the under
-side or base of the chair is small, and the rolling load large, the
-chair will very rapidly wear or imbed itself into the wood of the
-sleeper, shortening the life of the latter in a very palpable manner.
-The short narrow chair naturally gives less stability than the larger
-and broader chair. The chair shown in Fig. 292, which was much used
-for 75 lb. rails some twenty years ago, has much less base area and
-stability than the chair shown in Fig. 293, adopted for rails of a
-similar weight in the present day. The former had a bearing surface on
-the sleeper of only 53 square inches, as compared with 89 square
-inches in the latter. The base area of the chair must be in proportion
-to the weight it has to carry and distribute, and it would be false
-economy to stint the surface area of one of the details which
-influences so materially the stability and durability of the permanent
-way.
-
-As will be seen in Figs. 294, 295, and 296, the chairs at present used
-for 80, 85, and 90 lb. rails have a much larger bearing surface than
-the chair shown in Fig. 292.
-
-With the wider chair, a much longer and better seat can be given to
-the under table of rail, and a greater length of jaw for holding the
-wooden key. The longer the rail-seat the steadier the rail and the
-smoother the running.
-
-The keys are generally made of hard wood, sometimes compressed by a
-special process, cut slightly taper, or wedge, shape, and driven in
-between the jaw of the chair and the vertical web of the rail. On some
-railways the key is placed outside the rail, as in Fig. 297, and on
-others inside the rail, as in Fig. 298. The latter method possesses
-many advantages over the former. The outer jaw of the chair can be
-brought well up to the under side of head of rail, giving the rail
-more lateral support and better means of preserving the correct cant;
-and, as in this chair the outer jaw permanently fixes the gauge, the
-working out of one or more of the keys does not leave the rail exposed
-to be forced outwards and widen the gauge, as in the case with dropped
-keys in outside keying. Another and very important advantage of inside
-keying is that platelayers, when inspecting the road by walking
-between the rails, can readily examine the keys on both sides.
-
-[Illustration: Fig. 292, 293, 294, 295, 296, 297, 298, 299, 300, 301,
-302, 303, 304, 305, 306]
-
-Chairs have been made, as in Fig. 299, with a recess in the rail-seat,    209
-to hold a piece of prepared wood, or other suitable semi-elastic
-material, the object being to provide a rest, or cushion, softer and
-more yielding than the cast-iron. The idea looks well in theory, but
-in practice the pounding on the rail compresses or crushes the wood
-lower and lower into the recess, slackened keys have to be tightened,
-and when the wood has been worn or crushed away down to the level of
-the stop ribs, A, A, the under side of rail has no longer any
-seat, or rest, beyond the two narrow ribs of cast-iron. These afford
-such a very limited support that the rail becomes notched, and
-produces a very rough clattering road. It is a very simple matter to
-take out an old key and put in a new one, but to replace a wooden
-cushion in a chair recess involves the entire removal of either the
-rail or the chair. Chairs with wooden cushions have not been adopted
-to any great extent, the tendency of modern practice being to reduce
-as far as possible the number of parts of the permanent way, and to
-provide those parts with ample bearing or contact surfaces.
-
-Although the general practice has been to cast the chairs in one
-piece, chairs have been made in two pieces, as in Fig. 300, fastened
-together and to the rail by a bolt passing through the latter, the
-castings being secured to the sleeper with spikes. At first sight this
-pattern of chair appeared to possess some features in its favour. The
-castings were simple, keys were dispensed with altogether, and the
-under side of rail was not in contact with the cast-iron. A short
-experience, however, proved that the drawbacks far outweighed the
-apparent advantages. Holes for the through-bolts had to be punched at
-fixed distances in the rails, and although this could be readily done
-at the works, for the general use on the line it was necessary to
-resort to the tedious process of drilling by hand for a large number
-of holes on curves, and for rails cut to form _closers_.
-
-
-Sleepers.--Wood possesses so many suitable qualities that we can
-readily understand why it was early selected as the proper material
-for sleepers. It can be cut to any size and shape, holes can be bored,
-spikes can be driven, and bolts can be screwed into it without any
-difficulty and without causing injury to the timber, while the
-semi-elastic nature of wood absorbs the vibration of the rails and
-fastenings, and provides a sound-deadening seat so conducive to smooth
-running. Its only drawback is that it is perishable from wear and         210
-decay. Were it not for this defect, railway sleepers of wood might be
-considered as simply perfect.
-
-With a view to greater permanency and durability, stone sleepers were
-tried. These consisted of square blocks of good hard stone, measuring
-about 2 feet wide each way and 12 inches thick. Holes were cut in the
-stone, and plugs of hard wood inserted. The cast-iron chairs were then
-placed on the top of the blocks, and the iron spikes driven through
-the chair-holes into the wooden plugs. The elements of permanency were
-there certainly, but a rougher road it would be impossible to
-conceive. The stone was solid and unyielding, there was a total
-absence of softness and elasticity, and the harsh noisy effect
-produced when running over the stone-block road very soon became
-intolerable. Stone-block sleepers were found to be a failure, and were
-all removed. On some of our old lines, numbers of them, with the chair
-marks plainly visible, may be still seen in loading banks, buildings,
-sea walls, and other works for which they were never originally
-intended, but for which their size and weight render them very
-appropriate.
-
-Wooden sleepers are used in two forms, transverse and longitudinal. In
-the former, as in Fig. 301, the sleepers not only carry the rails, but
-also preserve the gauge; in the latter as in Fig. 302, the
-longitudinal sleepers only support the rails, additional timbers and
-strong fastenings being necessary to maintain the gauge.
-
-Longitudinal sleepers have been used to a large extent for bridge
-rails, it being supposed that with the broad continuous sleeper a
-lighter and shallower rail could be adopted, which would be equally
-efficient as a heavier rail on cross-sleepers. Excellent running roads
-have been made with longitudinal sleepers, notwithstanding the
-difficulty of making a good bridge-rail joint; but it is well to bear
-in mind that almost all the lines which originally adopted this form
-of permanent way have since reverted to the ordinary cross-sleeper
-road. The longitudinal sleeper road is an expensive road to lay down
-and maintain. The main pieces are of large scantling, must be of good
-quality of timber, and are consequently costly. The cross-pieces, or
-transomes, must be carefully fitted and secured with heavy ironwork.
-Where there is much traffic, the removal and renewal of one of the
-long timbers is much more difficult than the renewal of several ordinary  211
-cross-sleepers. Again, decay may take place on only one portion of a
-main timber, but there is no alternative but to remove the entire
-piece.
-
-For gauges varying from 4 feet 8½ inches to 5 feet 3 inches,
-cross-sleepers are cut to the length of 8 feet 11 inches, and are
-generally rectangular in section, as in Fig. 303, measuring 10 inches
-in width by 5 inches in thickness. On some of the lighter railways
-with small traffic, sleepers are often used only 9 inches wide by 4½
-inches thick, while occasionally on some lines, and in places where
-there is exceptionally heavy and constant traffic, sleepers 12 inches
-wide by 6 inches thick are adopted.
-
-Half-round sleepers, as in Fig. 304, are used on many lines because
-they are cheaper. In some cases the flat side of the sleeper is placed
-downwards, and the rail or chair is fastened into an adzed seat cut in
-the round side; and in the others the round side is placed downwards,
-and the flat side of the sleeper carries the rail or chair. Triangular
-sleepers, as in Fig. 305, have also been used, made by cutting the
-blocks diagonally, so as to obtain the greatest possible width. They
-were laid with the flat side upwards, and the apex downwards. They
-were difficult to keep packed, and have not been adopted to any great
-extent.
-
-With the exception of a limited number of larch and fir sleepers grown
-in the country, most of the sleepers for our home railways are
-imported from the Baltic. They are brought over in logs, or blocks,
-each 8 feet 11 inches long, some square and others circular in
-section, and when sawn down the middle, each block forms two sleepers.
-
-The preservation of timber from decay is a subject that very early
-occupied the attention of engineers and all those interested in
-railways. A railway sleeper is particularly exposed to deterioration
-the lower portion being surrounded with moist ballast, whilst the top
-portion is more or less uncovered--two different conditions in the
-same piece of timber. Several processes have been tried, such as
-Kyanizing, Burnetizing, Boucherizing, etc., but the system which has
-given the best results, and is now almost universally adopted, is that
-known as creosoting. This method consists of forcing liquid creosote,
-under considerable pressure, into sleepers or railway timbers which
-have been prepared or dried by ordinary natural seasoning or by
-special artificial means. Creosote is a dark, oily liquid, distilled      212
-from coal tar, varying in its composition according to the quality of
-the coal from which it is obtained, and ranging in its specific
-gravity from 11·08 to 10·28.
-
-Creosote oils of light specific gravity were at one time in favour,
-but experience proved that, to some extent, the light oils were
-volatile and also soluble in water, and that heavy rains washed out
-the constituents which were essential for the preservation of the
-timber. On the other hand, by heating the heavy oils and using high
-pressure the napthaline which is dissolved only by the heat, is forced
-into the wood, fills the pores, and solidifies.
-
-Creosote is obtainable in large quantities, at prices varying from
-twopence to fourpence per gallon, according to the demand and cost of
-production. Newly delivered sleepers or railway timber contain so much
-sap or water that it is impossible to force a sufficient quantity of
-creosote into them until they are properly seasoned or dried.
-
-The seasoning is generally arranged by sawing each block into two
-sleepers, and then stacking the sleepers on edge in tiers, leaving a
-space of four or five inches between each of them for a proper
-circulation of air. The sleepers should then be left for nine to
-twelve months to season, although more may be necessary in some cases
-if the blocks were particularly wet at the time they were sawn.
-
-When ready for the process the sleepers are placed in the creosoting
-cylinder, which is generally about 60 feet long by 6 feet in diameter
-with semi-spherical ends. One of the ends is fitted with strong hinges
-and fastenings, and forms the doorway. The sleepers are packed
-carefully inside, and the doorway made tight. The machinery is then
-set to work to exhaust the air from the cylinder and allow the
-creosote to flow in amongst the sleepers. When the cylinder is full
-the force-pumps are started to force in more creosote up to the
-pressure prearranged and regulated by the safety-valve, in some cases
-100, 110, or 120 lbs. per square inch. The creosote should be heated
-to 112° or 120° Fah., to dissolve the napthaline and reduce all the
-component parts to a thoroughly fluid condition.
-
-The success of creosoting depends almost entirely upon the effectual
-seasoning of the timber. Only a very small quantity of creosote can be
-forced into wet or unseasoned sleepers, even with the best machinery
-and exceptionally high pressures, while a thoroughly dry sleeper will     213
-readily absorb from 2⅓ to 3 gallons. More could be forced into the dry
-sleeper if necessary, but a little consideration will show there would
-be no advantage in doing so. In railway sleepers there are two
-elements of destruction at work--one the decay of the timber, and the
-other abrasion or wearing away of the wood itself from the constant
-pounding of the passing loads.
-
-More particularly does this wearing-away take place with the flange,
-or bridge, rails, their distributed bearing surface on the sleeper
-being less than the cast-iron chairs.
-
-A thoroughly well-creosoted 5-inch sleeper laid originally with a
-thickness of 4-¾ inches in the centre of rail-seat, as in Fig. 306,
-will wear down 1½ inches, the timber remaining quite sound.
-
-The writer has had to take out thousands of sleepers where the seats
-of the flange, or bridge, rails had been pounded or worn down so deep
-into the wood as to leave too small a thickness of timber to carry the
-rail with safety. These sleepers had to be taken out of the road, not
-on account of decay, but because they were actually worn down too thin
-to be of service. They had done their work well for a long series of
-years, and were perfectly sound when taken out. No increased quantity
-of creosote would have made them last longer, and any increased
-quantity of creosote would have been waste.
-
-Two and three quarter gallons of creosote is a very good and suitable
-quantity for a 10 inch by 5 inch rectangular sleeper, but not more
-than half this quantity can be forced in if the sleeper is wet or
-unseasoned.
-
-Sleeper-blocks are generally cut from the upper part of the tree, and
-do not therefore consist of the best portion of the timber, yet
-sleepers made from the soft, coarse-grained Baltic wood, properly
-creosoted, will last from twelve to eighteen years in the line in this
-country, while uncreosoted they would perish from decay in six or
-seven. The benefit is great when, by adding from eightpence to a
-shilling for the cost of creosoting, the life of the sleeper may be
-doubled or trebled. Of course, there are countries, like the far west
-of America, where the lines pass through vast forests, and where
-sleepers may be had for the mere cost of cutting. Creosoting in those
-places would be out of the question, and would cost four or five times
-the value of the plain sleeper. It is found, also, that in tropical
-countries and in dry climates at high altitudes creosote loses its        214
-efficiency, and in those districts the best creosoted soft-wood
-sleeper perishes from a species of dry rot in three or four years.
-Where wood sleepers have to be used in tropical climates it is better
-to obtain them from the timber of the district, although in many cases
-suitable trees are difficult to procure and the cost of land transport
-is very heavy.
-
-The soft cushion-like effect of a sound, properly packed wooden
-sleeper contributes so largely to form an easy, smooth-running road,
-that so long as they can be obtained at a moderate cost, and are
-fairly durable, wooden sleepers will always be preferred to those of
-any other material. The great question will be the supply. Creosoting
-and other wood-preserving processes have done much to prolong the life
-of sleepers, but the rapidly increasing extent of mileage throughout
-the world, together with the enormous number of sleepers required
-annually for maintenance or renewals, must before very long severely
-tax the powers of supply.
-
-In the great timber-producing territories the axe is often heard, but
-the planter is rarely seen. Vast forests are cleared away, and their
-sites transformed into busy towns or cultivated lands; and unless some
-great change takes place, and planting be carried out on a large
-scale, some other material will have to be adopted for this important
-item of our permanent way.
-
-Appearances would indicate that at no very distant date iron or steel
-will take a conspicuous part in the formation of future railway
-sleepers.
-
-More than thirty years ago several descriptions of cast-iron sleepers
-were introduced into notice and tried on some of our leading home
-railways. Cast-iron was at that time considered more suitable for the
-purpose than wrought iron, as it was very much less costly in price,
-and could be readily worked into any desired form or size, with the
-advantage that the castings would all be duplicates of one another.
-
-[Illustration: Fig. 307, 308, 309, 310, 311, 312, 313]
-
-Figs. 307 to 313 show some of the types that were designed and laid
-down in the road. In Fig. 307 the sleeper and chairs were all cast
-together in one piece; the rail was held in its place by wooden keys,
-and the gauge of the line was maintained by transverse wrought-iron
-tie-bars. The sketch represents one of the sleepers used at the
-rail-joints, and has three chairs, the larger one in the centre being
-for the support of the ends of the rails. This arrangement was the        216
-same as was then in use on the ordinary wood-sleeper road, where an
-extra large chair was placed at the rail-joints, and was the most
-approved method for many years before fish-plates were introduced. The
-intermediate sleepers were shorter, and had only two chairs.
-
-Fig. 308 represents a long, flat, cast-iron sleeper made in two
-halves, bolted together just below the under side of rail at each of
-the three chair-seats. The rail was gripped and held in position
-without the use of wooden keys. This being a joint sleeper, three
-chairs were used, as in Fig. 307. Only two chairs were used on the
-intermediate sleepers.
-
-Figs. 309 and 310 are somewhat similar, but the circular one is higher
-and more cup-shaped than the other of oval form. The oval pattern has
-two small recesses for holding two small hard-wood cushions. The
-circular holes shown in the sides of the sleepers were intended to
-facilitate the packing, or tamping, of the light sandy ballast.
-
-Fig. 311 represents a rectangular cast-iron sleeper, as used for the
-flange rail. The rail rests on cast-iron cross-ribs, bevelled to give
-the proper cant, and is held in position by the tie-bar bolt and
-clip-piece, as shown. The small projecting lug, formed on the under
-side of sleeper, fits into a corresponding notch in the tie-bar, and
-keeps the sleepers to gauge. The tie-bar passes through the loop end
-of the same bolt which secures the rail, and is held up tight against
-the under side of sleeper.
-
-Figs. 312 and 313, both the same in principle, possessed features
-which appeared to give great promise. They were simple in
-construction; the rail was kept well down, and did not come in contact
-with the cast-iron at any point. The long wooden wedges, which fitted
-into the rough or serrated sides of the casting, acted as a cushion to
-the rail, and were intended to sink deeper into the recess as the
-super-imposed weight increased, or the wood became thinner from
-shrinkage. In practice, however, it was found that these sleepers were
-not the success that was anticipated.
-
-It was soon observed that sand and fine particles of gravel from the
-ballast worked their way into the lower part of the recess, and became
-so compact as to prevent the wooden wedges working further down to
-increase their grip on the rail. Even when the recess was kept free
-and clear of sand, the enormous pressure exerted by the wooden wedges
-broke the iron at A, although an extra thickness was given to that        217
-part of the section. The cast-iron was exposed to the greatest strain
-at the point where it was the least capable of offering resistance.
-
-Much ingenuity was displayed in many of the patterns brought forward,
-but in dealing with a hard unyielding material like cast-iron, it is
-difficult, if not impossible, to impart any soft, elastic effect; and
-the different systems of cast-iron sleepers failed to become popular
-on our home railways, on account of the noise and vibration when
-trains passed over them. Another objection was the great multiplicity
-of parts required in many of the types, and the constant and severe
-strain produced on the fastenings on the passing of every wheel. The
-bolts might be made tight at first, but the incessant shaking would
-work them loose, the threads became stripped, and the rails ceased to
-be held in a proper and secure position.
-
-The cast-iron sleeper road was considered unsuitable for the heavy and
-fast traffic of our home lines, and was ultimately all taken up and
-replaced with wooden transverse sleepers. At the same time, there is
-no doubt that cast-iron sleepers have been of great value in India and
-tropical climates, where timber sleepers were not only scarce, but
-perish very rapidly. Very large numbers of them have been laid down
-abroad of patterns very similar to those shown in Figs. 309, 310, and
-311, and have done good service for many years. They are not affected
-by rain or heat, but, unfortunately, being castings, are liable to
-considerable annual loss from breakage.
-
-Improvements in plate-rolling machinery, and in appliances for bending
-and stamping wrought-iron, have materially assisted in developing the
-introduction of wrought-iron and steel sleepers. Cast-iron and
-wrought-iron are, in the abstract, hard and non-elastic as compared
-with wood; but whereas cast-iron can only be made into fixed,
-unyielding shapes, wrought-iron and steel can be worked into forms
-that possess a certain spring-like effect, which not only enables them
-almost entirely to resist fracture, but also imparts a measure of
-elasticity to the permanent way.
-
-The simplest form of wrought-iron sleeper would be a plain, flat
-plate, to which the chair, or rail-bracket, would be attached; but as
-this form would have bearing surface only, without any lateral hold on
-the ballast to keep the rails to line, it could not be adopted.
-
-During the last few years very many types of wrought-iron and steel       218
-sleepers have been introduced, and nearly all of them of the
-transverse-sleeper pattern, formed out of rolled plates; the sides,
-and in some cases the ends also, are bent, or turned down to obtain a
-hold in the ballast. Where bull-head or double-head rails are used,
-cast-iron chairs, or wrought-iron bracket chairs, are bolted, or
-otherwise secured to the upper surface of the sleeper, a layer of
-felt, tarred paper, or other soft material being placed between the
-two metal surfaces. Where flange rails are used, they are fastened to
-the sleepers either by bolts, clamps, or clips raised up out of the
-iron sleeper, and bent over to hold tightening keys. Rolled transverse
-sleepers can readily be bent, or set in the centre to give the proper
-cant at the rail-seat; and in some types the sleepers are pressed in
-the machines, so as to be narrower towards the centre, and with a
-deeper turnover, to obtain increased stiffness.
-
-In Figs. 314 to 319 are shown some of the patterns which have been
-brought out, laid down in actual practice, and in use at the present
-time.
-
-From the fact that wrought-iron and steel sleepers have been laid down
-in so many places where cast-iron sleepers were discarded or refused a
-trial, it is evident that the former are considered to have qualities
-which the latter did not possess. Rolled iron or steel sleepers are
-coming more and more into use, especially on foreign or colonial
-railways. So long, however, as good, well-creosoted timber sleepers
-can be obtained for our home railways at prices from 3_s._ 8_d._ to
-4_s._ 8_d._ each, and last from fourteen to twenty years, there is
-little probability that they will be supplanted by iron sleepers at
-double the cost. But abroad the circumstances of cost and durability
-are different, and there the rolled iron or steel sleepers, which will
-outlive two or three sets of wooden ones, must claim advantages which
-cannot be overlooked. The difficulty will be in the fastenings, the
-mode of attaching the rails to the sleepers. The constant hammering of
-metal upon metal, resulting from the vibrations of every passing load,
-will quickly wear or loosen bolts, rivets, or wedges, and the
-fastenings which will prove the most efficient will be those that are
-the simplest and most readily adjusted.
-
-
-Fastenings.--Figs. 320 to 335 illustrate some types of the principal
-fastenings used in connection with the chair road, and with
-flat-bottomed or flange rails.
-
-[Illustration: Fig. 314, 315, 316, 317, 318, 319]
-
-The fish-bolts, Figs. 320 and 321, are of a form which is in very         220
-general use both for steel bull-head rails and steel flange rails. By
-making the neck square or pear-shaped, to fit into corresponding hole
-in the fish-plate, the bolt is prevented from turning round when the
-wrench or spanner is applied to tighten the nut. A channel or groove
-is sometimes rolled on the outside of fish-plate to grip bolts made
-with square heads. Some engineers adopt two nuts, others prefer one
-nut of extra depth. Washers are used in some cases, but are not
-universal. With a deep rail it is preferable to place the nuts inside,
-so that the platelayer inspecting his length can see both rows of nuts
-as he walks along between the rails. With shallow rails the nuts must
-be placed outside and the cup-heads inside, to give ample clearance to
-the wheel-flanges.
-
-Fish-bolts are subject to very severe work. Heavy rolling loads
-passing over the rail-joints--frequently at very high speeds--bring
-into play all the gripping power of the fish-bolts to maintain a firm
-support of the fish-plates to ends of rails, and the constant action
-of pressure and release produces a loosening or unscrewing motion in
-the bolts which is very difficult to counteract. Loose fish-bolts
-cause clattering joints and uneven road, and unless promptly remedied,
-the screw threads are soon destroyed and bolts rendered useless. Many
-devices have been invented to prevent or check this loosening of the
-bolts; one of the methods, and a very simple one, consists of a plain
-steel bolt with a steel lock-nut, made as shown in Fig. 322. As will
-be seen from the section, one-half of the nut is tapped of the same
-size as the bolt, and the remainder with deep-locking threads. The
-first half of the nut is readily screwed on to the bolt, but
-considerable force must be exerted to screw on the portion having the
-deep-locking threads; practically the second half of the nut has to
-cut a new or deeper thread for itself when screwing round the bolt.
-
-[Illustration: Fig. 320, 321, 322, 323, 324, 325, 326, 327, 328, 329,
-330, 331, 332, 333, 334, 335]
-
-The slits or grooves at the angles of the nuts form four distinct
-cutting edges for shaping the deep threads. As the upper part of the
-lock-nut is divided by the grooves into four separate or detached
-segments, these segments will be forced slightly open or outwards
-during the action of cutting the deep thread on the bolt, and from
-their natural tendency to return to their original position they must
-exercise a strong gripping power on the bolt. This combined operation
-of cutting the deep threads and of forcing open the upper or detached     222
-segments, give an enormous holding and retaining power to the
-lock-nut, and enables it to withstand the train vibrations for a very
-long time without any perceptible slackening. In case of line repairs
-the nut can be readily unscrewed, and taken off the bolt.
-
-Round iron spikes, as in Figs. 323 and 324, and round wooden trenails,
-as in Fig. 325, are both used for fastening cast-iron chairs to the
-sleepers. The spikes are made with a slightly taper neck, of size
-rather less than the hole in the chair, to avoid risk of breaking the
-casting when driving the spike down. Trenails are made out of
-well-seasoned hard wood, and are compressed by machinery. When driven
-into the sleeper, they expand by exposure to the atmosphere, and hold
-the chair very securely in position; but being only wood and of very
-small scantling, they are subject to early decay. The head, which is
-the only part in sight, may be perfectly sound, while the part between
-the chair-seat and top of sleeper may be quite rotten and useless. It
-would be very risky to depend upon trenails alone; one spike at least
-should be used to every chair. In some cases an extra large trenail is
-used with an augur-hole down the centre, through which either an iron
-spike is driven or a bolt is passed and screwed into a crab-nut on the
-under side of the sleeper. This arrangement will work well for a time,
-but there will be a great deal of play in the spike or bolt when the
-trenail becomes much decayed.
-
-The spikes represented in Figs. 326, 327, and 328, are much used with
-flange rails. They are square in section, and finished with either
-blunt or sharp points, as shown. The top of spike is made with a
-doghead and side-lugs to facilitate the easing or withdrawal when
-necessary for renewals of sleepers, or alterations in line. By
-inserting the curved double claw end of a platelayers’ crowbar, the
-spike can be raised without injuring the sleeper; but if it is
-required to be driven into the same sleeper again, a new hole must be
-bored, as the old hole will be too slack to be of any service.
-Augur-holes must be bored in the sleepers for the above spikes. For
-new roads, these holes can be bored by machinery when cutting the
-grooves for rail-seats; but when carrying out alterations or repairs,
-a large number of spike-holes must be bored by hand-augurs, an
-operation both slow and laborious. With the hand-boring there is the
-danger that the hole may not be made deep enough, owing to the workman’s  223
-endeavour to avoid damaging the point of his augur by forcing it
-entirely through the sleeper, and bringing it in contact with a stone.
-Augur-holes bored wide to gauge will remain out of gauge, and although
-the spike may be driven down firm in its position, a space will be
-left for play between the rail-flange and spike.
-
-Fig. 329 is a sketch of a dog-spike for flange rails which the writer
-has used for many years both abroad and at home, and which can be
-driven without any boring at all. The back of this spike is made
-perfectly straight, half of the front side is made parallel to the
-back, and the remainder is tapered down to a chisel point not
-exceeding 1/16 of an inch thick, the entering edge on the face being
-narrowed down to 3/8 of an inch in width. Three jags or spurs are cut
-on each side of the tapered portion, or twelve in all, and add greatly
-to the holding power. Not only can this spike be driven without any
-boring, but it possesses the additional advantage that in driving it
-down its taper or wedge-like shape causes it to drift hard up to the
-edge of the flange of rail, an element of great value in securing the
-exact gauge of line. With these spikes permanent-way laying can be
-carried on very rapidly, and they are especially valuable when making
-alterations, as augurs for spike-boring can be dispensed with
-altogether.
-
-Wood screws with square heads similar to Fig. 330 are sometimes used
-for fastening flange rails to wooden sleepers. They are passed through
-holes punched or drilled in the flanges of the rails, and are intended
-to preserve the gauge as well as secure the rails to the sleepers.
-Experience has shown that these wood screws possess very limited
-holding power. The screwed portion of the bolt cuts but a very
-imperfect and weak holding thread in the soft wood of an ordinary
-sleeper, moisture insinuates itself into the bolt-hole, rusting the
-bolts and decaying the surrounding timber, and in a very short time
-the bolts become loose and incapable of holding the rail down firmly.
-As permanent-way fastenings wood screws are very inferior to crab
-bolts.
-
-Crab bolts, as in Fig. 331, may be made either with square or
-hexagonal heads, and with three spur-nuts or four spur-nuts, as in
-A or B. The length of the bolts will depend upon the thickness of
-the sleeper or timber-work through which they have to be inserted. The
-bolt is pushed down through the hole bored in the sleeper, and the
-crab-nut put on from underneath. With a few turns of the bolt, the        224
-crab-nut is brought close up to the under side of the sleeper, the
-spur-points become embedded in the wood, and hold the nut firmly in
-position during subsequent tightening of the bolt. Crab bolts are
-extensively used with flange or flat-bottomed rails, and also in
-switch chairs and in crossings. A large number of flange rails are
-used with one hole through the flange at each end of rail, and a crab
-bolt passed through the hole and through the sleeper next to the
-joint, as shown in Fig. 332. This system checks the creeping of the
-rails by effectually securing or anchoring each rail to two of the
-sleepers. As there is always a tendency for these rails to crack
-through to the outside at the flange-holes, it is very desirable to
-have as few holes as possible. The two above described will be found
-sufficient for all practical purposes. To avoid punching or drilling
-more holes in the flanges of the rails, additional or intermediate
-crab bolts can be used by means of the fang clips shown on Fig. 333.
-The crab bolt is passed through the fang clips and through the sleeper
-close up to the flange of rail, and by screwing it round in the
-crab-nut under the sleeper the fang-clip is pressed down until the two
-spurs are driven into the timber, and the rail held securely in its
-place and to gauge. Intermediate crab-nuts and fang-clips should
-always be used in pairs, one on each side of the rail. Possessing more
-holding-down power than ordinary spikes, they are particularly
-valuable on sharp curves.
-
-In some cases flange rails are laid in small cast-iron saddles, or
-chairs, as shown in Fig. 334, one end of the rail-seat having a recess
-to prevent the rail tilting upwards and outwards. An ordinary spike
-may be used for the inside end of chair, and a crab bolt with bent
-washer for the other. Unless the fastenings can be kept always tight,
-the above arrangement makes a very noisy, clattering road, as there
-are so many metal surfaces in contact, and so little to deaden the
-vibration. For narrow flange rails carrying heavy rolling load, chairs
-may be necessary to increase the bearing surface on the sleeper, but
-with rails having flanges five inches wide and upwards, it is better
-to let the flange rest direct on the wood of a properly grooved
-sleeper, and thus obtain a smoother and less noisy road.
-
-On exceptionally sharp curves, wrought-iron or steel tie-bars, as in
-Fig. 335, are sometimes used to maintain the line to gauge. They may
-be made out of bars 3 inches wide by ½ an inch thick, turned over at      225
-the ends to grip the outside flanges. Being made to exact template,
-they have to be threaded on to the rails before spiking down, and are
-placed between the sleepers at distances from 7 to 10 feet apart.
-
-
-Laying Permanent Way.--To preserve a good line and level to the
-permanent way, it is absolutely necessary that the road-bed should be
-kept thoroughly drained. If provision be not made for quickly carrying
-away the rain-water, and if it be allowed to collect under and around
-the sleepers, the action of the passing trains will work the finer
-particles of the packing into the consistency of soft mud, which will
-be gradually squeezed away, leaving the sleepers imperfectly supported
-and insecure. A loose sleeper involves a depression in the rails, and
-a corresponding lurch in the vehicles of the train, and a series of
-these depressions may produce such an oscillation in the train as to
-cause it to leave the rails.
-
-The height or space from formation-level to rail-level is generally
-about 1 foot 9 inches for a flange railroad, and about 2 feet for a
-chair railroad.
-
-Figs. 336 and 337 show cross-sections of both descriptions of road as
-laid down for a double line in cutting. The same arrangement applies
-to similar roads laid down in embankment, merely omitting the
-side-drains or water-tables. The bottom layer of ballast or road-bed
-should consist of good hard, quarried, or broken stones, each 6 inches
-deep, set on edge, firmly and closely hand-packed, forming a
-foundation through which the rain-water can be quickly carried away.
-On the top of this bottom pitching should be placed a 6-inch layer of
-broken stone ballast or strong clean gravel, of which none of the
-stones should be larger than will pass through a 2-inch ring. When the
-sleepers and rails have been laid on this second layer, and properly
-packed to line and level, the top ballasting, or boxing, of either
-broken stones or strong clean gravel, should be filled in to the form
-and extent specified. Where broken stones are used for the top
-ballasting none of them should be larger than will pass through a
-1½-inch ring.
-
-Broken stone ballast should only be made from the hardest and soundest
-description of rock or boulders, so that, however small the particles,
-they will remain sharp and clean.
-
-[Illustration: Fig. 336, 337, 339, 338, 340, 341, 342, 343, 344]
-
-There are many kinds of rock which appear hard and compact when first
-excavated, but upon exposure to the weather undergo a complete change,    227
-developing into soft masses containing too much clay to allow the
-water to pass through readily. Where rock is scarce and gravel
-plentiful, the lower layer may be made of the heavier or coarser
-gravel, leaving the finer gravel for the upper layer, or boxing; but
-there is no doubt that the broken stone pitching makes the most
-efficient bottom layer. No gravel ballast should be used which is not
-free from clay or earthy sand.
-
-Wherever there are particles of earthy matter, sufficient to furnish
-nourishment for vegetable growth, weeds will quickly spring up, and
-once established are most difficult, if not impossible, to eradicate.
-The presence of weeds checks drainage, and gives an untidy appearance
-to the line, besides constantly occupying a large portion of the
-platelayers’ time in their removal.
-
-Clean cinders, free from dust or earth, are much used for upper
-ballast and boxing, and being lighter than gravel, are specially
-applicable for soft boggy ground. Burnt clay, broken into small
-pieces, has been largely adopted in districts where both rock and
-gravel were difficult to obtain. Chalk, furnace-slag broken small,
-crushed brick and sand, are frequently used as ballast. Sand is
-objectionable where there is high-speed traffic, as the finer
-particles rise in the form of dust and deposit themselves on the
-vehicles and machinery of the train.
-
-The water-tables, or side drains in the cuttings, should be cut below
-the formation level, and to a depth or width sufficient to take away
-all rain-water, or water arising from springs. Where the material of
-the cutting is of a loose friable nature, it may be necessary to
-protect the sides of the water-tables with low dry stone walls, as in
-Fig. 338; or glazed earthenware pipes may be laid, as in Fig. 339,
-with open joints, or with grate openings at regular intervals. In some
-cases substantial side-walls and invert are requisite to carry away
-the flow of water.
-
-Timber sleepers intended for the flange railroad should have the
-rail-seats grooved by machinery to ensure perfect accuracy in the
-position of the grooves, and in the angle or inclination of the
-rail-seats. Fig. 340 is a side view of part of a sleeper grooved to
-receive a flange rail. The presence of the grooves materially
-facilitate the laying of the rails to gauge, but must not be allowed
-to interfere with the constant use of the platelayer’s gauge. In a
-similar manner the timber sleepers for the chair road frequently have     228
-the spike-holes bored to template by machinery, as indicated on Fig.
-341. Steel or iron sleepers are delivered with the recesses for rails,
-and holes for bolts or fastenings formed complete by machinery.
-
-The distances apart of the sleepers will be regulated in a great
-measure by the weight of the rails and the description of the traffic.
-Where light rails are intended to carry heavy engines the sleepers
-must be laid closer together than would be necessary for heavy rails.
-The joint being the weakest part of the rail, it is usual to put the
-sleepers closer together at that place, with a view to gain additional
-support, to assist the fish-plates in preserving as much as possible a
-firm unyielding surface at the rail-joint.
-
-Fig. 343 shows an arrangement of sleepering largely adopted for steel
-flange rails 26 feet long, and weighing 79 lbs. per yard. The length
-of a rail is more a question of convenience of handling, facility of
-transhipment, and general use, than of actual manufacture. There is no
-difficulty in rolling rails up to 50 feet in length, or more; but very
-long rails are extremely ungainly things to move about, and are more
-exposed to receive permanent bends or kinks in unloading, besides
-requiring greater spaces at the joints to allow for contraction and
-expansion.
-
-Fig. 344 is an example of sleepering for a chair railroad, for steel
-bull-head rails 26 feet long, and weighing 85 pounds per yard.
-
-Line stakes and level pegs must be put in at suitable distances to
-guide the platelayers in laying the rails to the correct line and
-level, and on the curves the proper amount must be marked off for the
-super-elevation of the outer rail.
-
-When the second layer of ballast has been spread for its full width
-and depth the sleepers can be distributed, and the rails or chairs
-spiked down to the correct gauge. Before putting on the fish-plates
-spaces must be left at the ends of the rails to allow for contraction
-and expansion, the amount depending upon the temperature at the time
-of laying down the rails. As the rails will expand, or increase in
-length, with the heat, it is necessary to allow more space for
-expansion for rails laid down in the cold, or winter months. On our
-home railways rails are very rarely laid down when the temperature is
-lower than 25° F., or higher than 125° F., and this range of 100° may
-be considered as covering all the variations likely to occur in
-ordinary practice. The greater portion of the permanent-way laying is     229
-carried on when the temperature is between 40° and 75°. The results of
-very carefully conducted experiments show that an increase of
-temperature of 1° F. will cause an iron or steel bar, or rail, to
-expand or lengthen to the extent of seven one-millionths of its
-length. Working this out for a range of 100° F. would give an increase
-in length of seven hundred one-millionths, which would be equal to an
-extension of 0·2184 of an inch in a 26-foot rail. For our home
-railways, therefore, a space of 5/16 of an inch will be found amply
-sufficient to meet the variations in length between the extremes of
-winter and summer, for a rail from 26 feet to 30 feet in length. Too
-much allowance for expansion is detrimental to the rails, because
-where the spaces are excessively large the wheels drop into the hollow
-and hammer or spread the ends of the rails.
-
-The fish-bolts should not be completely tightened up until the
-permanent way is thoroughly set, and packed to its finished line and
-level.
-
-On straight line the rail-joints should be laid square and opposite to
-each other. Permanent-way laying with broken joints is rarely adopted,
-except on curves or station-yards.
-
-On curves the joints of the inner rails gain on the joints of the
-outer rails to the extent of--
-
-  radius + gauge
-  -------------- × length of rail.
-      radius
-
-The amount of this gain, or lead, is adjusted by cutting off a portion
-of the end of the inner rails at certain intervals.
-
-Assuming the fish-bolt holes to be spaced as shown on Fig. 342, then,
-when the inner rail is leading to the extent of 2 inches, a piece 4
-inches long is cut off, as shown by dotted lines, leaving the original
-second fish-bolt hole to serve as first or end fish-bolt hole, and a
-new or second bolt-hole is drilled by hand at A. This method sets back
-the joint 2 inches from the square, and the lead is allowed to go on
-again until it becomes necessary to cut off another piece of 4 inches.
-Another mode is to have a proportion of the rails rolled 2 or 3 inches
-shorter for use on the curves.
-
-On curves of a 1000 feet radius and upwards, the rails should be laid
-to the normal gauge, but on curves of lesser radius the gauge may be
-slightly increased, and as much as ¾ of an inch allowed on a curve of
-500 feet radius.
-
-The amount of cant, or super-elevation, to be given to the outer rail     230
-on curves must be regulated by the speed of the train and the gauge of
-the line. Many formulæ have been compiled to determine the necessary
-amount of super-elevation, but experience has shown that by some of
-them the calculated amounts were excessive. Possibly during past years
-too much cant has been given in many cases. The following simple
-formula approaches very closely to practical experience--
-
-  (velocity in miles per hour)^2 × gauge in feet   {the super-elevation
-  ----------------------------------------------- ={ of outer rail
-                    radius in feet × 1·25          { in inches.
-
-For high-speed trains uniformity of cant is of the utmost importance,
-more so even than the exact amount. Any irregularity in the
-super-elevation of the outer rail, sometimes high and sometimes low,
-will produce a dangerous swaying movement in the train, which, if not
-promptly checked, would lead to derailment.
-
-More injury is done to curves by spreading, arising from rigid
-wheel-bases of engines and tenders, than from any want of
-counteraction to centrifugal force.
-
-When a long length of permanent way has been linked in, rails spiked
-to gauge, and fish-plates bolted together, the platelayers can proceed
-to the final adjustment to line and level in accordance with the
-stakes and pegs provided for their guidance. The setting to exact line
-is effected by means of long pointed round iron crowbars, which are
-struck forcibly into the ballast alongside the rails, and serve as
-powerful hand-levers to pull or push the rails to the right or left as
-directed by the foreman standing some distance back at one of the
-line-stakes. The men with the crowbars pass from rail-length to
-rail-length, until a long stretch of road has been pulled into correct
-line.
-
-The adjustment to rail-level is done by first packing up the sleepers
-to the correct height at the various level-pegs, and then packing up
-the intermediate sleepers so that the surface of the top of the rails
-forms one uniform even line from level-peg to level-peg. On new lines
-it is usual to pack a little high in the first instance to allow for
-the subsidence or compression which invariably takes place on the
-passage of heavy trains over fresh ballast.
-
-The form or contour line of the top ballast will vary according to        231
-circumstances. In station-yards it is usual to fill in the ballast
-almost up to the level of the top of the rails for the convenience and
-safety of the men who are constantly moving about marshalling the
-carriages and waggons. Out on the open line between stations, the
-ballast on some railways is filled in up to rail-level, while on
-others it is only filled in up to the tops of the sleepers, leaving
-the rails and chairs quite clear of the ballast. On others, again, the
-ballast is filled well up to the rails and channelled in the centre,
-as shown on the sketches Figs. 336 and 337. Channelling the centre of
-the road reduces the quantity of ballast per mile, ensures good
-drainage, and also stability by not permitting any central support to
-the sleepers. By covering up the lower table and sides of rails the
-noise is reduced to a minimum, vibration is absorbed, and a more
-silent road is the result. The contact with the ballast also preserves
-the rail from the extremes of temperature. Where the ballasting is not
-channelled there is some risk of the sleepers breaking in the middle.
-The constant packing of the sleepers just under the rails has a
-tendency to drift some of the ballast inwards towards the middle of
-the sleeper, forming a hard compact mass, and this mass, acting as
-fulcrum, throws considerable strain on the middle of the sleeper when
-the trains pass over and depress the ends. Where the ballast is filled
-in level with the rails on top of sleepers it should be loosened
-occasionally in the middle to prevent it becoming too hard.
-
-Connections with the rails of the main line will have to be made in
-various forms to suit the circumstances of the joining lines or
-sidings.
-
-Fig. 345 shows a simple double-line junction.
-
-[Illustration: Fig. 345, 346, 347, 348, 349, 350, 351, 352, 353, 354,
-355, 356]
-
-Fig. 346 shows an example of what is termed a _flying junction_, or a
-junction of two double lines arranged in such a manner as to cause the
-least interruption to a constant train traffic passing UP and
-DOWN over both lines. Upon referring to Fig. 345 it will be seen
-that a train from F, turning off at the points E and proceeding to
-G, must block, or close for traffic the section ABC during its
-passage over that line towards G. With a crowded train-service the
-blocking of both UP and DOWN main lines for the working of one
-train would cause much interruption, and to obviate such delay the
-_flying junction_ is substituted. Fig. 346 shows how a train from F
-is turned off at the points J and proceeds on to K, where by means
-of a bridge it passes either over or under both main lines, and           233
-continues on to G without in any way interfering with the train
-service on ABC.
-
-Fig. 347 is an ordinary plain siding or _turn-out_, including the
-necessary throw-off or trap-points and short dead end.
-
-Fig. 348 is an ordinary _cross-over road_ from DOWN main line to
-UP main line, and _vice versâ_.
-
-Fig. 349 is a double cross-over road, generally termed a _scissors_
-cross-over.
-
-Fig. 350 is a simple through cross-over road from DOWN main line
-to siding alongside UP main line.
-
-Fig. 351 is a similar arrangement of through cross-over road with the
-addition of a pair of slip points at S to make a connection with the
-UP main line, thus combining the facilities of the ordinary
-cross-over and through cross-over road.
-
-Fig. 352 shows a set of three throw-switches with all the sliding
-tongues placed side by side; and Fig. 353 shows another arrangement of
-three throws with the sliding-rails of the second set of switches
-placed just behind the heel of the first set of switches. The latter
-method works very well where there is sufficient length for the
-purpose.
-
-Fig. 354 shows a square crossing, where one line of railway crosses
-another line of railway on the same level.
-
-Fig. 355 shows a connection with a siding by means of an ordinary
-carriage or waggon turn-table.
-
-Fig. 356 shows a set of “runaway” points which are sometimes placed in
-the main line at the top of an incline close to a station, the object
-being to intercept or throw off any portion of a train which may have
-become detached, and which would, if unchecked, run away back down the
-incline. By means of a weighted lever or spring the points are set to
-the normal position of _open_ to the siding, and as they are
-“trailing” points for the running road they are readily closed by a
-passing train. One or other of the above forms of connections, or a
-combination of them, will meet all the requirements which usually
-occur in railway work.
-
-Fig. 357 is an enlarged sketch of an ordinary cross-over road, and
-Fig. 358 of a double or _scissors_ cross-over.
-
-[Illustration: Fig. 357, 358]
-
-Fig. 359 shows a _single-slip_ point connection, and Fig. 360 a
-_double-slip_ point connection. In places where slip connections can
-be introduced they add greatly to the facilities for train movements      235
-without curtailing the available standing-room for vehicles on the
-lines and sidings. They are simple in construction, do not require
-crossings, and in many cases save a complete cross-over road. At the
-same time slip connections can only be laid down where the angle of
-the intersecting lines is sufficiently flat to admit of a connecting
-curve of workable radius.
-
-Fig. 361 is an enlarged sketch of a set of ordinary 15-foot switches
-or points. By placing them about the middle of the stock rails the
-joints of the latter are kept well beyond the sliding rails, and the
-road is held firmly together. It is necessary to place the sleepers
-closer together at the switches to allow for the reduction in section
-of the sliding rails, which results from planing them down to the
-requisite shape. By substituting two long timbers for the ordinary
-sleepers at the points of the switch rails, as shown on the sketch, a
-more efficient support is obtained for the switch-box or crank in the
-case of rod-worked switches, and the working distance from the rails
-is accurately maintained, irrespective of any packing or pulling of
-the road. In the sketch a steel bull-head rail is shown on one side,
-and a steel flange rail on the other, each bolted to an ordinary
-cast-iron switch chair. Switch chairs are sometimes made of plates of
-wrought-iron or steel, forged to the correct shape, and riveted
-together. They are, however, much more costly than cast-iron chairs,
-and deteriorate more quickly from corrosion.
-
-[Illustration: Fig. 359, 360]
-
-Fig. 362 is an enlarged sketch of an ordinary crossing similar to the
-one indicated at C (Fig. 359), and composed of a cast-steel
-reversible block. The ends and lugs, L, L, are formed to suit the
-connecting rails and fish-plates, as shown in the cross-sections. The
-casting is secured to the crossing timbers by bolts passing through
-the side lugs, S, a cast-iron packing-washer, W, being placed
-between the lug and the timber to ensure a solid seat and avoid
-rocking. A very important point in the construction of these block
-crossings is to have the groove or flange-path sufficiently deep to
-prevent the striking or touching of the flange of a much-worn tyre. A
-well-made, carefully annealed steel-block reversible crossing is very
-smooth in the road, and has a long life. It is all in one solid piece;
-there are no parts to work loose or spread; the wear of the running
-surface is very uniform, and when the one side is much worn down,
-there is the other ready for service. The writer has had many of these
-steel-block reversible crossings in use under heavy and fast traffic      237
-for six and eight years without turning.
-
-Fig. 363 shows an ordinary crossing made of steel bull-head rails
-secured in strong cast-iron chairs; and Fig. 364 is a similar crossing
-made of steel flange rails. In some cases the two rails forming the
-V are welded together at the point B, and in others they are
-riveted or bolted together. Fig. 365 shows a diamond or through
-crossing similar to the one indicated at D, Fig. 359, made of steel
-bull-head rails and chairs.
-
-Crossings are constructed in a variety of forms, whether on the
-principle of the cast-steel block, or made out of ordinary steel
-rails; and the above sketches merely illustrate some well-recognized
-types which experience has proved to be efficient and durable in the
-road. The angles of the crossings will depend upon the divergence of
-the intersecting lines to be connected; ordinary crossings, to the
-angle of 1 in 10, work in for very general use in station-yards, but
-many are required of angles varying from 1 in 6 to 1 in 14, and in
-some cases 1 in 16.
-
-As a rule, engineers endeavour as far as possible to avoid using
-ordinary crossings flatter than 1 in 12, or diamond crossings flatter
-than 1 in 9, because the gap between the running rails becomes very
-considerable beyond those angles. At the same time, there are many
-cases of ordinary crossings of 1 in 16, and diamond crossings of 1 in
-12 and 1 in 13 laid down in exceptional places, and which have carried
-heavy and fast traffic for many years. All crossings should be well
-protected with wing rails and guard rails, as shown on the sketches.
-
-Fig. 366 illustrates a method of bringing the UP and down lines of a
-double line of railway close to each other, and passing them over a
-single-line opening bridge, or a bridge where the works for the second
-line have not been completed. This arrangement avoids the necessity of
-any switches, and prevents any accidents which would arise from a
-misplaced switch. Each set of trains is effectually kept to its own
-line of rails. With proper signalling or pilot working, the
-double-line traffic can be worked over the single-line bridge without
-difficulty. The writer has adopted the above arrangement in many cases
-when renewing double-line bridges or viaducts where the width for
-traffic working has been restricted to half of the bridge.
-
-[Illustration: Fig. 361, 362, 363, 364, 365]
-
-In some instances the same system has been extended to the carrying of    239
-four lines of rails over a double-line bridge, as shown on Fig. 367.
-
-The principal tool used by platelayers for lifting the permanent way
-is a long iron-shod wooden lever, as shown in Fig. 368. The point of
-the lower end is pushed under the sleeper, and the curved shoulder
-placed on a large stone or piece of wood as a support, and then by
-pulling down the upper end of the lever the road can be lifted to the
-height required. Screw lifting-jacks of various kinds are also used
-for the same purpose, the foot or base of the jack resting on the
-ballast, while the claws grasp the under side of the rail, and raise
-it by means of the screw. With appliances which lift by the rails, the
-sleepers have to be raised by the holding power of the spikes or
-bolts, an operation which is apt to throw undue strain on spikes.
-Where possible it is preferable to lift from the under side of the
-sleepers.
-
-Beaters similar to the one shown on Fig. 369 are used for packing the
-ballast. One end of the beater is pointed like a pick, and serves to
-loosen the ballast or broken stone, and the other end is made somewhat
-in the hammer-head form to pack or beat the ballast under the sleeper.
-With skilled men the beater is a most useful tool, speedy and
-effective in its action. Held in both hands, it is raised slightly,
-and then brought down sharply, the hammer-head striking the gravel or
-broken stone placed alongside for packing under the sleeper. A series
-of smart blows can be given with rapidity and without requiring any
-great muscular effort. In some foreign countries there is difficulty
-in initiating the natives to work with the ordinary beater, on account
-of the stooping position necessary for its use. To meet this
-difficulty the writer has in many cases substituted a packing or
-tamping bar, as shown in Fig. 370. This bar, about 5 feet long, is
-made of light round wrought-iron or steel, with a ring-shaped handle
-at one end, and an ordinary beater head at the other. The workman
-using this bar stands upright, guides the bar, held loosely, with his
-left hand, and with his right gives a continuance of smart blows. This
-tool works well in the hands of light active natives, who can thus
-give a number of rapid strokes without much exertion.
-
-[Illustration: Fig. 366, 367, 368, 371, 369, 370, 372]
-
-The simple rail-bender, or _Jim Crow_, of the form shown in Fig. 371,
-is much used by platelayers for giving a slight bend or set to rails
-which have to be laid down on sharp curves on main line or cross-over
-roads. The rail is laid across the two arms, and the screw turned round   241
-and downwards by means of an iron bar lever used as a spanner or
-wrench to the nut shown on the sketch. The same tool is also
-serviceable for straightening rails which have become crooked or
-kinked. Large and more comprehensive machines are used for bending
-rails in large quantities or setting them to exact curvature, but,
-being heavy and cumbersome, they are rarely taken away from the
-store-yards.
-
-Strong steel shovels of the form shown in Fig. 372 are the most
-suitable for platelayers’ general use when working with gravel, sand,
-or broken stones.
-
-For driving iron spikes and wooden keys in cast-iron chairs a
-long-handled hammer is the most convenient for work, and its long
-swinging action produces considerable force without much actual
-labour.
-
-Road-gauges, nut-wrenches, short straight-edges, spirit-levels,
-ratchet-drills, augurs, and cold setts of well-tempered steel for
-cutting rails, are all required by the men engaged in laying permanent
-way.
-
-The following summaries give the estimated cost of materials alone for
-one mile of steel bull-head rail and steel flange rail permanent way
-of different weights. The 90-lb. steel bull-head rail is at present
-the heaviest of that section laid down to any extent on our home
-railways, and the chairs and fastenings are made heavy to correspond
-to the rail and the traffic for which it is intended. As the rails in
-the summaries become lighter, the weights of the chairs and fastenings
-are decreased. As yet there are not many samples of the 100-lb. steel
-flange rail; but in those places where it has been laid down it has
-been supported with a liberal supply of sleepers, to obtain increased
-bearing surface. With a 5½-inch flange, and a rectangular sleeper 10
-inches wide, the bearing surface on the wood is only about 55 square
-inches, as compared with about 100 square inches, the bearing surface
-of a large cast-iron chair for a heavy bull-head rail. As previously
-explained, a small bearing surface on a sleeper tends to the cutting
-down into the wood, and rendering the sleeper unsafe and useless even
-before it has become unserviceable from decay: hence the reason for
-ample bearing surface on the sleeper. The last two summaries refer to
-3-foot narrow-gauge lines. In more than one instance the 45-lb. rails
-first laid down have been found much too light for the engines
-required to work the traffic, and when making extensions of the system    242
-65-lb. rails have been adopted. Indeed, when taking into consideration
-the weight of most of the narrow-gauge engines, generally from 24 to
-28 tons in working order, and their short wheel-base, it would appear
-that a 65-lb. rail is the minimum which should be used both for
-stability and economy in maintenance.
-
-The summaries are prepared from examples in actual use, and represent
-the number and weight of sleepers, chairs, and fastenings in each
-instance. Even with the same weight of rail, the practice differs on
-various lines as to the weights of the chairs and fastenings; and the
-selections have been made to show a fair average. On some railways the
-chairs are secured partly by tree-nails and partly by spikes, or crab
-bolts; on others only spikes are used. The prices put down are the
-estimated values of the materials delivered into the Permanent Way
-Stores of our own home railways, and are exclusive of all costs of
-freight, carriage, or distribution to the site of laying down. The
-prices are only comparative, and fluctuate up or down according to the
-current value of the raw materials from which the various items are
-manufactured. Lighter rails and smaller fastenings cost more per ton
-than those of a heavier type, as they involve more labour and
-workmanship.
-
-             STEEL BULL-HEAD RAILS (90 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  -------------------------------+--------------------+----------+----------
-                                 |  Weight per mile   |  Price.  |  Amount.
-                                 |  of single line.   |          |
-  -------------------------------+--------------------+----------+----------
-                                 |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 90 lbs. |                    |          |
-    per yard (30-ft. lengths)    | 141    8   2    0  |  5  0  0 | 707  2  6
-  Steel fish-plates (deep),      |                    |          |
-    41 lbs. per pair             |   6   10   0    0  |  6 15  0 |  43 17  6
-  Fish-bolts and nuts            |   1    4   0    0  | 12 15  0 |  15  6  0
-  2112 creosoted sleepers,       |                    |          |
-    9 ft. × 10 in. × 5 in.       |        --          |  0  3 10 | 404 16  0
-  4224 cast-iron chairs,         |                    |          |
-    each 50 lbs.                 |  94    5   3    0  |  3 10  0 | 330  0  1
-  8448 iron cup-headed spikes    |   3   15   2    0  | 10  0  0 |  37 15  0
-  8448 tree-nails, at per 1000   |        --          |  3 10  0 |  29 11  4
-  4224 oak keys, at per 1000     |        --          |  5  0  0 |  21  2  5
-  -------------------------------+--------------------+----------+----------
-                                                                £|1589 10 10
-  ---------------------------------------------------------------+----------
-
-
-             STEEL BULL-HEAD RAILS (85 LBS. PER YARD).                    243
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  -------------------------------+--------------------+----------+----------
-                                 | Weight per mile    |  Price.  |  Amount.
-                                 | of single line.    |          |
-  -------------------------------+--------------------+----------+----------
-                                 |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 85 lbs. |                    |          |
-    per yard (26-ft. length )    | 134    0   0    0  |  5  0  0 | 670  0  0
-  Steel fish-plates (deep),      |                    |          |
-    38 lbs. per pair             |   6   17   3    0  |  6 15  0 |  46  9 10
-  Fish-bolts and nuts            |   1    4   3    0  | 12 15  0 |  15 15  7
-  2030 creosoted sleepers,       |                    |          |
-    9 ft. × 10 in. × 5 in.       |        --          |  0  3 10 | 389  1  8
-  4060 cast-iron chairs,         |                    |          |
-    each 45 lbs.                 |  81   11   1    0  |  3 10  0 | 285  9  5
-  8120 iron cup-headed spikes    |   3   12   2    0  | 10  0  0 |  36  5  0
-  4060 tree-nails, at per 1000   |        --          |  3 10  0 |  14  4  2
-  4060 oak keys, at per 1000     |        --          |  5  0  0 |  20  6  0
-  -------------------------------+--------------------+----------+----------
-                                                                £|1477 11  8
-  ---------------------------------------------------------------+----------
-
-
-             STEEL BULL-HEAD RAILS (80 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  -------------------------------+--------------------+----------+----------
-                                 | Weight per mile    |  Price.  |  Amount.
-                                 | of single line.    |          |
-  -------------------------------+--------------------+----------+----------
-                                 |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 80 lbs. |                    |          |
-    per yard (26-ft. lengths)    | 125   14   0    0  |  5  0  0 | 628 10  0
-  Steel fish-plates (deep),      |                    |          |
-    37 lbs. per pair             |   6   14   1    0  |  6 15  0 |  45  6  2
-  Fish-bolts and nuts            |   1    4   3    0  | 12 15  0 |  15 15  7
-  2030 creosoted sleepers,       |                    |          |
-    9 ft. × 10 in. × 5 in.       |        --          |  0  3 10 | 389  1  8
-  4060 cast-iron chairs,         |                    |          |
-    each 40 lbs.                 |  72   10   0    0  |  3 10  0 | 253 15  0
-  8120 iron cup-headed spikes    |   3   12   2    0  | 10  0  0 |  36  5  0
-  4060 tree-nails, at per 1000   |        --          |  3 10  0 |  14  4  2
-  4060 oak keys, at per 1000     |        --          |  5  0  0 |  20  6  0
-  -------------------------------+--------------------+----------+----------
-                                                                £|1403  3  7
-  ---------------------------------------------------------------+----------
-
-
-             STEEL BULL-HEAD RAILS (75 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 75 lbs.|                    |          |
-    per yard (26-ft. lengths)   | 117   0    0    0  |  5  0  0 | 585  0  0
-  Steel fish-plates (deep),     |                    |          |
-    35 lbs. per pair            |   6   7    0    0  |  6 15  0 |  42 17  3
-  Fish-bolts and nuts           |   1   4    3    0  | 12 15  0 |  15 15  7
-  2030 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 389  1  8
-  4060 cast-iron chairs,        |                    |          |
-    each 37 lbs.                |  67   1    1    0  |  3 10  0 | 234 14  5
-  12,180 iron cup-headed spikes |   5   8    3    0  | 10  0  0 |  54  7  6
-  4060 oak keys, at per 1000    |       --           |  5  0  0 |  20  6  0
-  ------------------------------+--------------------+----------+----------
-                                                               £|1342  2  5
-  ------------------------------+--------------------+----------+----------
-
-
-             STEEL BULL-HEAD RAILS (70 LBS. PER YARD).                    244
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 70 lbs.|                    |          |
-    per yard (26-ft. lengths)   |  110  0    0    0  |  5  0  0 | 550  0  0
-  Steel fish-plates (deep),     |                    |          |
-    32 lbs. per pair            |    5 16    0    0  |  6 15  0 |  39  3  0
-  Fish-bolts and nuts           |    1  2    0    0  | 12 15  0 |  14  0  6
-  2030 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 389  1  8
-  4060 cast-iron chairs,        |                    |          |
-    each 34 lbs.                |   61 12    2    0  |  3 10  0 | 215 13  9
-  8120 iron cup-headed spikes   |    3  3    2    0  | 10  0  0 |  31 15  0
-  4060 oak keys, at per 1000    |       --           |  4 10  0 |  18  5  5
-  ------------------------------+--------------------+----------+----------
-                                                               £|1257 19  4
-  --------------------------------------------------------------+----------
-
-
-             STEEL BULL-HEAD RAILS (65 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  -------------------------------+--------------------+----------+----------
-                                 | Weight per mile    |  Price.  |  Amount.
-                                 | of single line.    |          |
-  -------------------------------+--------------------+----------+----------
-                                 |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel bull-head rails, 65 lbs. |                    |          |
-    per yard (26-ft. lengths)    |  102  3    0    0  |  5  5  0 | 536  5  9
-  Steel fish-plates (deep),      |                    |          |
-    28 lbs. per pair             |    5  1    2    0  |  7  0  0 |  35 10  6
-  Fish-bolts and nuts            |    1  1    0    0  | 13  0  0 |  13 13  0
-  2030 creosoted sleepers,       |                    |          |
-    9 ft. × 9 in. × 4½ in.       |       --           |  0  3  0 | 304 10  0
-  4060 cast-iron chairs,         |                    |          |
-    each 28 lbs.                 |   50 15    0    0  |  4  0  0 | 203  0  0
-  8120 iron cup-headed spikes    |    2 19    0    0  | 10 10  0 |  30 19  6
-  4060 oak keys, at per 1000     |       --           |  4  0  0 |  16  4  9
-  -------------------------------+--------------------+----------+----------
-                                                                £|1140  3  6
-  ---------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (100 LBS. PER YARD).
-       _Estimated Cost of Materials for One Mile of Single Line._
-
-  -------------------------------+--------------------+----------+----------
-                                 | Weight per mile    |  Price.  |  Amount.
-                                 | of single line.    |          |
-  -------------------------------+--------------------+----------+----------
-                                 |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 100 lbs.   |                    |          |
-    per yard (30-ft. lengths)    |  157  3    0    0  |  5  0  0 | 785 15  0
-  Steel fish-plates (deep),      |                    |          |
-    42 lbs. per pair             |    6 12    0    0  |  6 10  0 |  42 18  0
-  Fish-bolts and nuts            |    1  5    0    0  | 12 15  0 |  15 18  9
-  2464 creosoted sleepers,       |                    |          |
-    9 ft. × 10 in. × 5 in.       |       --           |  0  3 10 | 472  5  4
-  8448 dog-head spikes           |    3  6    0    0  | 12 10  0 |  41  5  0
-  704 fang clips                 |    0  8    3    0  | 13 10  0 |   5 18  2
-  1408 crab bolts                |    1  6    3    0  | 12 10  0 |  16 14  5
-  -------------------------------+--------------------+----------+----------
-                                                                £|1380 14  8
-  ---------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (79 LBS. PER YARD).                     245
-       _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                |  Weight per mile   |  Price.  |  Amount.
-                                |  of single line.   |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 79 lbs.   |                    |          |
-    per yard (26-ft. lengths)   | 125   0    0    0  |  5  0  0 | 625  0  0
-  Steel fish-plates (deep),     |                    |          |
-    37 lbs. per pair            |   6  14    1    0  |  6 10  0 |  43 12  8
-  Fish-bolts and nuts           |   1   4    0    0  | 12 15  0 |  15  6  0
-  2030 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 389  1  8
-  6496 dog-head spikes          |   2  10    3    0  | 12 10  0 |  31 14  5
-  812 fang clips                |   0  10    0    0  | 13 10  0 |   6 15  0
-  1624 crab bolts               |   1  10    3    0  | 12 10  0 |  19  4  5
-  ------------------------------+--------------------+----------+----------
-                                                               £|1130 14  2
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (74 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 74 lbs.   |                    |          |
-    per yard (30-ft. lengths)   | 116   5    3    0  |  5  0  0 | 581  8  9
-  Steel fish-plates (deep),     |                    |          |
-    30½ lbs. per pair           |   4  15    3    0  |  6 10  0 |  31  2  5
-  Fish-bolts and nuts           |   1   1    0    0  | 12 15  0 |  13  7  9
-  1936 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 371  1  4
-  6336 dog-head spikes          |   2   9    2    0  | 12 10  0 |  30 18  9
-  704 fang clips                |   0   8    3    0  | 13 10  0 |   5 18  2
-  1408 crab bolts               |   1   6    3    0  | 12 10  0 |  16 14  5
-  ------------------------------+--------------------+----------+----------
-                                                               £|1050 11  7
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (65 LBS. PER YARD).
-    _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 65 lbs.   |                    |          |
-    per yard (30-ft. lengths)   | 102   3    0    0  |  5 10  0 | 561 16  6
-  Steel fish-plates (deep),     |                    |          |
-    27 lbs. per pair            |   4   4    3    0  |  7  5  0 |  30 14  5
-  Fish-bolts and nuts           |   1   0    0    0  | 13  0  0 |  13  0  0
-  1936 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 371  1  4
-  6336 dog-head spikes          |   2   9    2    0  | 12 10  0 |  30 18  9
-  704 fang clips                |   0   8    0    0  | 13 10  0 |   5  8  0
-  1408 crab bolts               |   1   6    3    0  | 12 10  0 |  16 14  5
-  ------------------------------+--------------------+----------+----------
-                                                               £|1029 13  5
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (60 LBS. PER YARD).                     246
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                  |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 60 lbs.   |                    |          |
-    per yard (30-ft. lengths)   | 94    5    3    0  |  5 10  0 | 518 11  7
-  Steel fish-plates (deep),     |                    |          |
-    25 lbs. per pair            |  3   18    2    0  |  7  5  0 |  28  9  2
-  Fish-bolts and nuts           |  1    0    0    0  | 13  0  0 |  13  0  0
-  2112 creosoted sleepers,      |                    |          |
-    9 ft. × 10 in. × 5 in.      |       --           |  0  3 10 | 404 16  0
-  7040 dog-head spikes          |  2   15    0    0  | 12 10  0 |  34  7  6
-  704 fang clips                |  0    8    0    0  | 13 10  0 |   5  8  0
-  1408 crab bolts               |  1    6    3    0  | 12 10  0 |  16 14  5
-  ------------------------------+--------------------+----------+----------
-                                                               £|1021  6  8
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (50 LBS. PER YARD).
-     _Estimated Cost of Materials for One Mile of Single Line._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 50 lbs.   |                    |          |
-    per yard (30-ft. lengths)   | 78   11    2    0  |  5 15  0 | 451 16  1
-  Steel fish-plates (deep),     |                    |          |
-    22 lbs. per pair            |  3    9    1    0  |  7 10  0 |  25 19  5
-  Fish-bolts and nuts           |  0   18    0    0  | 13 10  0 |  12  3  0
-  2112 creosoted sleepers,      |                    |          |
-    9 ft. × 9 in. × 4½ in.      |       --           |  0  3  0 | 316 16  0
-  7040 dog-head spikes          |  2    7    1    0  | 13  0  0 |  30 14  3
-  704 fang clips                |  0    6    1    0  | 14  0  0 |   4  7  6
-  1408 crab bolts               |  1    2    0    0  | 13  0  0 |  14  6  0
-  ------------------------------+--------------------+----------+----------
-                                                               £| 856  2  3
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (65 LBS. PER YARD).
-  _Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge)._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 65 lbs.   |                    |          |
-    per yard (30-ft. lengths)   |102    3    0    0  |  5 10  0 | 561 16  6
-  Steel fish-plates (deep),     |                    |          |
-    27 lbs. per pair            |  4    4    3    0  |  7  5  0 |  30 14  5
-  Fish-bolts and nuts           |  1    0    0    0  | 13  0  0 |  13  0  0
-  2288 creosoted sleepers,      |                    |          |
-    6 ft. × 9 in. × 4½ in.      |       --           |  0  2  3 | 257  8  0
-  7744 dog-head spikes          |  2   17    0    0  | 12 10  0 |  35 12  6
-  704 fang clips                |  0    7    2    0  | 13 10  0 |   5  1  3
-  1408 crab bolts               |  2    2    0    0  | 12 10  0 |  26  5  0
-  ------------------------------+--------------------+----------+----------
-                                                               £| 929 17  8
-  --------------------------------------------------------------+----------
-
-
-               STEEL FLANGE RAILS (45 LBS. PER YARD).                     247
-
-  _Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge)._
-
-  ------------------------------+--------------------+----------+----------
-                                | Weight per mile    |  Price.  |  Amount.
-                                | of single line.    |          |
-  ------------------------------+--------------------+----------+----------
-                                |tons. cwt. qrs. lbs.| £  s. d. |  £  s. d.
-  Steel flange rails, 45 lbs.   |                    |          |
-    per yard (26-ft. lengths)   | 70   14    1    0  |  5 15  0 | 406 12  0
-  Steel fish-plates (deep),     |                    |          |
-    16 lbs. per pair            |  2   18    0    0  |  7 10  0 |  21 15  0
-  Fish-bolts and nuts           |  0   18    0    0  | 13 10  0 |  12  3  0
-  2233 creosoted sleepers,      |                    |          |
-    6 ft. × 8 in. × 4 in.       |       --           |  0  1 10 | 204 13 10
-  7308 dog-head spikes          |  2   14    0    0  | 13  0  0 |  35  2  0
-  812 fang clips                |  0    5    0    0  | 14  0  0 |   3 10  0
-  1624 crab bolts               |  0   18    0    0  | 13  0  0 |  11 14  0
-  ------------------------------+--------------------+----------+----------
-                                                               £| 695  9 10
-  --------------------------------------------------------------+----------
-
-
-
-
-  CHAPTER IV.                                                             248
-
-  Stations: Station Buildings, Roofs, Lines, and Sidings.
-
-
-Stations.--When selecting a site for a station, not only should due
-regard be paid to the proximity and convenience of access to the town
-or place to be served, but attention should be given to the gradients
-of the line near the proposed station. If it can possibly be avoided,
-a station should not be placed in a hollow at the foot of two
-inclines, as such a position would always entail heavy work starting
-trains on the ascending gradients, with the risk of sliding back into
-the station again in unfavourable weather; and for arriving trains
-there would be increased difficulty in properly controlling the
-vehicles on the descending gradients so as to bring them to a stand in
-the event of any sudden stoppage being required. With stations on a
-summit, having gradients falling in each direction, the starting
-trains can get away more readily, and the arriving trains have the
-benefit of the rising gradient to assist them in coming to a stand.
-Possibly the best selection would be a long length of level, both in
-the station proper and for a considerable distance on each side; but
-it is not often that such a combination can be obtained without
-incurring extra expenditure. The station-yard itself should, however,
-be on the level, or as nearly so as possible, for the convenience and
-safety of marshalling or shunting carriages or waggons. No siding
-should be laid on such a gradient as would render it possible for
-vehicles to start into motion during high winds. Carriages and waggons
-having good oil axle-boxes will start themselves on a gradient of 1 in
-300 under the influence of a moderately strong breeze, and a slight
-push will start them on a gradient of 1 in 400.
-
-The number and arrangement of the lines, sidings, platforms, loading
-banks, and other conveniences of a station, will depend upon the
-description and amount of traffic to be accommodated. There is a wide     249
-range from the simple village station, with its one short siding, to
-the great city terminus, with its labyrinth of lines and sidings, and
-its groups of platforms, offices, warehouses, and other accessories.
-Each station should be laid out with a view to meet the special
-requirements of the principal traffic likely to arise, whether
-passenger, timber, coal, stone, cattle, or general merchandise, and
-ample space should be retained to permit further enlargement and
-additional sidings at any future time. If provision is not made for
-the latter in the outset it will certainly lead to large expenditure
-at some later date. Land adjoining a railway station is quickly
-appropriated by the public on account of its proximity and convenience
-for conveyance, and soon covered with store-yards, warehouses, and
-other buildings, and when any portion of these have to be acquired for
-station enlargements, they can only be obtained at a large cost, very
-often ten times as much as the value of the original ground.
-
-When laying out approach roads to goods or passenger stations, whether
-intermediate or terminal, due importance should be given to the
-advantage of making them wide, easy in gradient, and fairly straight.
-A narrow, crooked access to a busy goods yard is a great impediment to
-the expeditious working of a heavy traffic; and road waggons conveying
-long pieces of timber or ironwork along such a route, would be very
-apt to block the roadway and delay the passage of other vehicles. A
-steep gradient will prevent the carriers taking full loads, and will
-add to the cost and time of delivery.
-
-[Illustration: Fig. 373]
-
-An approach road to a large passenger station should be laid out with
-a long frontage to a wide footpath to enable the numerous intending
-passengers to alight conveniently from the conveyances which bring
-them to the station. A portion of the footpath and carriage-way in
-front of the entrance to the booking-hall should be covered over with
-a light roof to provide shelter during inclement weather. The footpath
-should be on the same level as the vestibule or booking-hall, so that
-the public may pass at once to the ticket-office and their luggage be
-wheeled on hand-barrows direct to the platform or luggage-room. Every
-effort should be made to avoid introducing steps from the footpath to
-the booking-hall, as they check the proper ingress of the passengers,
-and are very severe on elderly persons and invalids, besides
-necessitating the dilatory method of carrying each piece of the
-passengers’ luggage by hand. Experience has shown the inconvenience of    251
-steps to be so great that in many cases a large expenditure has
-afterwards been incurred to do away with them, and bring the
-setting-down footpath to the same level as the booking-hall. For a
-large station the booking-hall should be spacious and well provided
-with separate ticket windows for the different classes of passengers
-and districts of the line; and the access or communication with the
-platform should be ample and free from obstruction. Small doors and
-narrow passage-ways check the movements of the passengers and create
-confusion and delay.
-
-Waiting-rooms for the different classes of passengers,
-inquiry-offices, luggage-rooms, lavatories, etc., will have to be
-provided according to the amount of traffic to be accommodated. In
-large stations it may be necessary to have two or more groups of such
-rooms to suit the different sets of platforms.
-
-At the most important terminal stations of our home railways it is
-usual to lay down the main-line arrival platforms with a cab or
-carriage rank alongside, so that the passengers alighting from the
-railway carriages have merely to walk across the platforms, and step
-into the cabs or vehicles waiting to take them and their luggage away
-from the station. This arrangement is not only a great convenience to
-the passengers, but expedites the clearing of the platform and the
-making way for another incoming train. It would not, however, be of
-any service on continental lines, or other foreign railways, where all
-arriving luggage must first be taken to the general luggage room, to
-be examined by the local customs, or _octroi_ officers, before being
-allowed to pass out of the station.
-
-[Illustration: Fig. 374, 375]
-
-Main-line departure platforms should be of ample width to allow of the
-free movement of the passengers, ticket examiners, officials, and men
-wheeling passengers’ luggage. The accommodation should not only be
-sufficient for the normal traffic, but allowance should be made for
-the large crowds which may assemble for excursion trains during the
-holiday season or other occasions of national gathering. Additional or
-local platforms, frequently termed _dock platforms_, may be required
-for suburban trains, and may be made narrower in width, and without
-cab ranks, as the passengers using them only travel short distances
-and rarely have more luggage than they carry in their hands. These
-dock platforms are generally made available for outgoing as well as       253
-incoming trains. The lengths of the main-line or local platforms will
-be regulated by the number of carriages forming a train.
-
-Fig. 373 is a diagram sketch of a large terminal passenger station,
-with main and local platforms as above described. It is merely typical
-to illustrate the principle, and may be multiplied and varied to any
-extent in the way of lines and platforms. In the sketch the main
-groups of offices, waiting-rooms, etc., are shown at the end of the
-station; but they may be equally well placed at the side, as their
-actual location is principally a question of proximity or convenience
-of access to some main street or thoroughfare. The lower or
-platform-level rooms of such a building are mainly devoted to the
-public for booking-offices, waiting-rooms, refreshment-rooms,
-lavatories, offices for parcels, telegraph and inquiry, suitable rooms
-being set apart for lamps, foot-warmers, guards, and porters. Above
-this lower story a range of offices can be built for the use of the
-principal officers and staff of the different departments of the
-company.
-
-Fig. 374 is a plan of a small terminal station on a single line of
-railway, where the passenger traffic is small, and one platform is
-made to serve alternately both for arrival and departure trains. The
-booking-hall, waiting-rooms, offices, etc., are laid down parallel to
-the line of rails, and the approach road and footpath are parallel to
-the building. The platform roof extends to the outer wall, and
-provides shelter for the passengers on the platform, and forms a shed
-for the carriages at night.
-
-Fig. 375 is a sketch of an intermediate or roadside station on a
-single line of railway. All the offices, waiting-rooms, etc., are on
-one platform, which serves for trains travelling in either direction.
-The dotted lines show the additions which would be necessary to make
-the station a stopping-place for trains working in opposite
-directions.
-
-Fig. 376 shows an ordinary intermediate or roadside station on a
-double line of railway, with two passenger platforms, and a connection
-between them either by subway or over-line footbridge. The principal
-offices and waiting-rooms are shown on the one side, and only small
-waiting-rooms, etc., on the other.
-
-[Illustration: Fig. 376]
-
-[Illustration: Fig. 377, 378]
-
-[Illustration: Fig. 379, 380]
-
-[Illustration: Fig. 381, 382]
-
-Fig. 377 is a sketch of a double-line intermediate or roadside station
-at the junction of a small single-line branch railway. Branch-line
-passengers to and from the main DOWN-line trains merely walk across
-the platform to get into their respective trains, and those to or from    258
-the main UP trains walk across the footbridge or subway to get to the
-opposite platform.
-
-Fig. 378 is a plan of a double-line roadside station, with two
-main-line passenger platforms and a dock line and platform for the use
-of local or branch-line trains. This arrangement is applicable where
-the actual junction with the main line is at a little distance from
-the station, but not sufficiently far away to warrant an additional
-junction station as shown in Fig. 377.
-
-Fig. 379 shows a similar roadside station laid out with a more
-comprehensive arrangement of dock-lines and platforms. The lines
-alongside the main passenger platforms are _turn-outs_ from the
-main-line proper, and leave the latter free for the passage of fast
-through trains or goods trains when an ordinary passenger train is
-standing alongside the platform. In this way a fast non-stopping train
-can overtake and be sent forward in advance of a slow passenger train.
-
-Fig. 380 shows a roadside station with two double platforms, the inner
-lines and platforms being reserved for main-line passenger trains, and
-the outer lines for branch-line trains. By this arrangement carriages
-can be quickly transferred from a branch-line train to a main-line
-train, and _vice versâ_; access from the public road, or from one
-platform to the other, can be obtained either by subway or over-line
-footbridge.
-
-Fig. 381 is a sketch plan of an island platform for a double-line
-roadside station, near which there are junctions with two branch
-lines. The UP and DOWN main lines run alongside the wide
-portion of the platform, and the branch lines run into the two dock
-platforms. The waiting-rooms, refreshment-rooms, etc., are placed in
-groups on the wide platform, spaces being left between the blocks for
-the convenience of access from side to side. The booking-office and
-parcels-office are placed alongside the approach road on the higher
-level. An over-line footbridge extends from the booking-hall to the
-dock platforms, terminating with steps on one side and an inclined
-ramp of 1 in 8 on the other. In carrying out the above plan for a
-railway on an embankment, the access from the booking-hall to the
-platform would be provided by a subway instead of an over-line
-footbridge.
-
-Fig. 382 shows another form of island platform, also arranged for
-UP and DOWN main-line trains, and two branch-line trains. The
-access is obtained from a public-road over-line bridge crossing the       259
-railway, and the booking-office is placed at the top of an incline, or
-ramp, leading down to the platform. The dock-line platforms are
-arranged different to those in the preceding example, with the object
-of providing longer platforms for the main-line trains. This result,
-however, is obtained at some little inconvenience to the dock-line
-trains, as the passengers from one of these must walk round a portion
-of two platforms to get into the other dock-line train, instead of
-merely walking across the platform as in Fig. 381.
-
-In some cases of island platforms the total width of the station
-buildings and platforms is made much greater than indicated in the
-above sketches, and a wide, easy incline constructed from an over-line
-public-road bridge, to allow cabs and carriages to come down to a
-large paved area between the platforms, for the convenience of setting
-down and taking up the train passengers and their luggage.
-
-The island-platform arrangement possesses many advantages for the
-exchange of passenger traffic. All the platforms are connected and on
-one level, and passengers, together with their luggage, can be quickly
-transferred from one train to another. One set of waiting-rooms,
-refreshment-rooms, etc., are sufficient, and are available for the
-passengers of all the four trains. A smaller number of station men are
-required for the work, as the staff can be more concentrated and
-better utilized than when there are separate platforms on opposite
-sides of the line.
-
-The number, size, and arrangement of waiting-rooms and other offices
-for the public at a large station will depend upon the amount and
-description of traffic to be dealt with at the particular station
-under consideration. Where the passenger traffic is to a large extent
-of a local or short distance character, a moderate amount of
-waiting-room space may be sufficient, as these local passengers
-regulate their arrival so as to avoid waiting any great length of time
-for the trains. An enormous suburban passenger traffic is carried on
-in many places with a very limited waiting-room accommodation, the
-frequency of the trains and the routine of the travellers reducing the
-necessity of such rooms to a minimum. A more ample waiting-room space
-will be necessary when providing for a large, long journey, or through
-traffic, and for stations at seaports, as the intending passengers,
-particularly those landing from steamers, generally reach the station
-a considerable time before the departure of the trains to take them       260
-forward. For this class of traffic it will also be necessary to
-provide suitable refreshment-rooms. At large terminal stations it is
-frequently found more convenient for the working of the traffic to
-have two or more sets of waiting-rooms, etc., separating the local and
-long-journey passengers, and placing the rooms alongside the
-corresponding platforms.
-
-Lavatories and conveniences at large stations should be provided on a
-liberal scale, and fitted up in the most substantial and efficient
-manner. Not only should they be thoroughly well ventilated, but they
-should have abundance of light. Nothing tends so much to ensure order
-and cleanliness in these places as plenty of light.
-
-It will frequently be found that at many of the large important
-stations there are local surroundings and circumstances of level and
-foundations, which will to a great extent influence the arrangement of
-the rooms and offices to be devoted to the public service. No fixed or
-standard type could be adopted for all cases. Each one will have to be
-studied out to suit the locality, and the grouping must be made to
-work in with the best facilities obtainable. In all such cases one of
-the principal points is to select a convenient position for the
-booking-hall, easy of access to all persons entering the station
-premises. On no account should the ticket-office be placed in a
-position tending to block the thoroughfare on to the platforms. A
-large number of intending passengers may already be in possession of
-tickets, and the station arrangements should enable these passengers
-to proceed at once to the platforms without having to struggle or
-force their way through crowds of other passengers gathered round the
-ticket windows. In some instances it is found expedient to provide
-auxiliary booking-offices for excursion traffic, to be used only on
-special occasions, thus restricting the principal booking-offices to
-the ordinary main-line booking.
-
-When laying out small intermediate or roadside stations for either
-double or single line, or small terminal stations on short branch
-lines in thinly populated districts, it becomes a question how to
-provide the requisite statutory accommodation with a minimum amount of
-building. The following sketches taken from actual examples may be of
-use for reference.
-
-Fig. 383 shows the smallest size of station building that can very
-well be constructed to be of any practical service. It comprises an
-office for the station-master, who has to attend to the tickets,          261
-parcels, and telegraph; a waiting-hall with glazed front; a small
-waiting-room and W.C. for ladies; and a yard with conveniences for
-gentlemen, coal store, etc. Access to the station is obtained through
-a gateway in the platform fencing.
-
-Fig. 384 shows a somewhat similar arrangement, but with two additional
-rooms. The road approach to the station is brought alongside and
-parallel to the building, and access to the platform is obtained by
-passing through the booking-hall, which has a glazed front to the
-line.
-
-Fig. 385 gives the particulars of a building containing rather more
-accommodation than the two preceding examples.
-
-Fig. 386 shows a small terminal station for a short branch line where
-there is a moderate tourist traffic during the season. In addition to
-the regular station accommodation, a refreshment-room is added for the
-convenience of those passengers who have to drive into the country, or
-have arrived at the station by road conveyance. The platform roof,
-which is extended out over the line of rails, as shown on the
-transverse section, forms a complete covering for the platform, and
-serves for a carriage-shed at night.
-
-The above sketches merely illustrate types of some small stations
-suitable for home or colonial lines, and may be built of stone, brick,
-concrete, iron, or timber. For towns of more importance, the offices
-and rooms would have to be increased both in number and size. On
-foreign lines it is customary to provide an office and large hall
-fitted up with counters for the use of the Local Excise Authorities in
-the examination of passengers’ luggage; and at some stations one or
-more rooms have to be set apart for the use of the military
-authorities.
-
-Narrow platforms should always be avoided, especially in front of the
-offices and waiting-rooms. Nothing tends more to check the proper
-expeditious working of the traffic than a confined space for the
-movement of the passengers and of the station staff carrying luggage.
-
-[Illustration: Fig. 383, 384, 385]
-
-[Illustration: Fig. 386]
-
-In cases where the traffic will warrant the expenditure, it will be
-found an advantage to construct a light roof or verandah over a
-portion of the platforms of roadside stations. This covering will
-provide a convenient shelter for the passengers and their luggage, and
-prevent the crowding of booking-halls and doorways during inclement
-weather. In hot countries a verandah or awning of some description on
-the platforms is an absolute necessity, and those travellers who have     264
-had any experience of railways under a tropical sun, will call to mind
-the celerity with which the passengers seek such welcome shade.
-
-A very important item in the construction of a large terminal station
-is the roof over the lines and platforms. Wrought-iron and steel can
-now be obtained in so many convenient sections, and at such moderate
-prices, that timber-framed roofs, except for very small spans, are now
-rarely used for railway work. The metallic structure is much lighter
-in appearance and more durable, besides being less exposed to
-destruction by fire. The introduction of iron and steel has enabled
-roofs to be constructed of very much larger spans than would have been
-prudent to have attempted in timber; at the same time it must be kept
-in mind that, notwithstanding this increased facility of construction,
-the cost of a roof per relative area covered increases very rapidly as
-the span increases. The extent of space to be roofed over in some of
-our modern terminal stations is so large that the question of
-roof-spans to be adopted has to be considered very carefully. It has
-been argued by some that if the area be divided out into small or
-moderate spans, the presence of the rows of columns for supporting the
-roof might preclude the possibility of any future re-location of the
-lines and platforms except by an entire rearrangement of the
-roof-work. On the other hand, it may also be stated that railway
-engineers have now obtained such a thorough experience of the
-necessary relative proportions of platforms and carriage-lines for
-large stations, as to enable them to lay out these works without any
-risk of requiring alterations for many years.
-
-[Illustration: Fig. 387, 388, 389, 390, 391, 392, 393]
-
-[Illustration: Fig. 394, 395, 396, 397, 398]
-
-[Illustration: Fig. 399, 400, 401, 402]
-
-[Illustration: Fig. 403, 404, 405]
-
-[Illustration: Fig. 406]
-
-[Illustration: Fig. 407, 408, 409, 410]
-
-There are so many descriptions of roof-principals used in railway
-stations that it would be impossible here to introduce more than a few
-examples. Figs. 387 to 405 illustrate by diagram sketches a series of
-types taken from actual practice. Fig. 406 gives more in detail the
-particulars of the roof-principal of 60 feet span, Fig. 392. As will
-be noted from Fig. 406, the width of 120 feet between the walls is
-divided into two spans of 60 feet each, the ends of the principals in
-the centre of the 120 feet being carried on arched wrought-iron
-girders of 48 feet span, supported on strong ornamental cast-iron
-columns placed at 48-foot centres. The rain-water from the large
-centre gutter is taken down inside the columns and conveyed away to
-drainage pipes laid down for the purpose. The 60-foot principal above
-described forms a very strong roof, and is light in cost and              271
-maintenance. The weight of ironwork, both wrought and cast, in the
-principals, arched wrought-iron girders, cast-iron columns, centre
-gutters, etc., is only 0·51 of a ton per square (of 100 square feet)
-of area covered. For comparison, the weight of ironwork in the roof,
-Fig. 402, of 198 feet span is 1·42 ton per square of area covered; and
-of the roof, Fig. 404, of 210 feet span, is 2·07 tons per square.
-
-This increase in weight per square as the spans go on increasing
-results, not only in a much larger outlay for original construction,
-but entails also a proportionally heavier expenditure for maintenance
-and painting. The item of painting alone is an expensive one in all
-iron-roof work, and must be attended to regularly for the proper
-protection and appearance of the ironwork. With the smaller spans, the
-roof-trusses form very convenient supports for painters’ scaffolding
-or planking, but with the very large spans the greater height and the
-form of the roof-principals render specially designed scaffolding and
-appliances necessary for the painting and repairs.
-
-Doubtless there is something very attractive about a large span roof,
-its bold outline stretching from side to side of a wide covered area
-imparts an imposing effect which cannot be claimed for smaller or more
-moderate spans; but where roofs are constructed for purely utilitarian
-purposes it becomes a question worthy of grave consideration whether a
-series of smaller spans would not provide the same practical benefits
-as would be obtained from one very large span. Upon referring to the
-typical sketch of a terminal station, Fig. 373, it will be seen that
-the total width from inside to inside of main walls is 240 feet. The
-lines and platforms are so arranged that by placing rows of columns at
-A, A, B, B, and C, C, the entire width may be divided out into four
-spans of 60 feet; or, if preferred, a row of columns at B, B may be
-adopted, resulting in two spans of 120 feet, or the entire width may
-be included in one large span of 240 feet. Any one of the three
-arrangements will provide an effectual roof-covering, and the
-selection must be decided by the cost or expediency.
-
-Another way to avoid the introduction of large span-roof principals,
-and to preserve the covered area free from intervening columns, is to
-erect strong truss-girders extending across at right angles from the
-main walls. These truss-girders are placed at suitable distances, and     272
-carry simple roof-principals of convenient spans. In some cases the
-roof-principals are placed as shown in Figs. 407 and 408, and in
-others as in Fig. 409.
-
-In another system the roof-principals are incorporated with the main
-truss-girders, as in Fig. 410.
-
-With the above type of covering the truss-girders take the place of
-the arched wrought-iron girders and cast-iron columns, as illustrated
-in Fig. 406, but will be more costly, as may be gathered from the
-following brief comparison: Assuming the area to be covered as 480
-feet long and 180 feet wide, then the width of 180 feet could be
-divided into three spans of 60 feet each, or one centre span of 65
-feet, and two of 57 feet 6 inches if they would work in more
-conveniently. With columns at 48-foot centres longitudinally, the
-three-span arrangement would contain the following:--Twenty cast-iron
-columns in the two rows, or twenty-two columns if two columns are
-placed side by side at the extreme end; 960 lineal feet of light
-arched wrought-iron girders in twenty girders of 48 feet span.
-
-On the other hand, with the truss-girders placed at 40-foot centres to
-suit roof-principals resting on the tops of girders, as shown in Fig.
-409, or to suit the arrangement shown in Fig. 407, there would be
-twelve heavy truss-girders, each of 180 feet span, making a total
-length of 2160 lineal feet of deep truss-girder work, exclusive of
-about another 60 lineal feet, which would be required for the bearings
-on the side walls.
-
-The successful lighting by day of a large roofed-in station will
-depend principally upon an appropriate distribution of the glazed
-portions. With a large span, and the glass skylights placed near the
-apex, the side lines and platforms will be much less efficiently
-lighted than those near the centre; and again, if the glazed parts are
-only at the sides, then the centre portion will be rather in the
-shade. Where possible it is better to place the glazed portions and
-slated portions alternately, so as to obtain a more uniform light all
-over the centre area, somewhat similar to the arrangement shown in
-Fig. 406.
-
-Roofs over passenger platforms at roadside stations are made in many
-types, the arrangement depending in a great measure upon the width of
-platform to be covered. In many of the earlier stations the roof was
-extended across from side to side, and included the lines of rails as
-well as the UP and DOWN platforms, a system which was not only
-costly, but had the disadvantage that the steam and smoke from passing    273
-trains remained for some time under the roof before it was thoroughly
-dispersed. The more modern and more economical plan is to put the roof
-or shelter over the platforms only, and allow the steam and smoke to
-pass away into the air. In designing the latter class of roof, the
-fewer supporting columns the better, so as to diminish as far as
-possible the obstructions on the platforms. Where the platform is
-unavoidably narrow, the roof may be carried on curved brackets
-projecting out from the walls.
-
-Except in tropical countries, where shade is more acceptable than
-strong light, a liberal amount of glass should be provided in these
-platform roofs. On many of our home railways they are entirely covered
-with glass, and the abundance of light is found to be of great
-assistance in the working of the traffic. Figs. 411 to 420 are
-sketches of a few out of the many types of small roofs which have been
-erected over single and island platforms.
-
-
-Goods-sheds.--The form and dimensions of a goods-shed for any
-station must be determined by the description and amount of traffic to
-be transacted at the particular place. With an estimate of the traffic
-before him, the engineer must consider the internal arrangement of
-building most suitable for the bulk of the merchandise to be
-accommodated. The principal object of the shed is to permit of goods
-being transferred under cover from or to railway trucks or carts
-without being exposed to the weather, and the transfer will be
-expedited if the arrangements are made the most convenient for the
-particular class of merchandise presented.
-
-For some commodities it is considered preferable to unload direct from
-the railway trucks into carts, or _vice versâ_, and thus have only one
-handling of the goods. To comply with this method, the cartway must be
-made almost down to the same level as the rails, to allow the carts or
-drays to be drawn close up alongside the railway trucks, as shown in
-Figs. 427 and 428. This type of shed implies a constant supply of
-carts, so as not to detain the railway trucks, or necessitate the
-stacking or storing of goods on the low level floor in the way of
-carting movements.
-
-[Illustration: Fig. 411, 412, 413, 414]
-
-[Illustration: Fig. 415, 416, 417, 418, 419, 420]
-
-[Illustration: Fig. 421, 422, 423, 424, 425]
-
-[Illustration: Fig. 426, 427, 428, 429]
-
-For general merchandise in boxes or bales, a raised loading-bank
-inside the shed is usually found to be the most convenient arrangement
-both for loading and unloading. The top of the loading-bank should be
-a little below the level of the railway-truck floor to give clearance
-to all truck-doors opening outwards. By means of short portable
-gangways or landings, the moderate-sized packages are readily             278
-transferred to or from the trucks, either by hand or by small
-two-wheeled trolleys, the heavier pieces being lifted by cranes. The
-cartway should run parallel to the rails on the opposite side of the
-loading-bank, and may be either inside or outside the building,
-according to the importance of the place. When the cartway is inside,
-the entire front of the loading-bank is available for cart traffic,
-but this advantage entails a considerable increase in the size and
-cost of the building. When the cartway is outside, the cart traffic is
-worked through large doorways placed at suitable distances, and fitted
-with projecting roofs or awnings to protect the goods during the
-loading or unloading. At some of these doorways, short docks about 10
-feet square, or more, are formed in the loading-bank, into which the
-carts may be set back fairly into the shed for the greater convenience
-of the transhipment of the goods by hand or crane power. Where the
-stacking space is ample, the contents of several railway trucks may be
-discharged on to the loading-bank without any delay in waiting for
-carts, and the same railway trucks may be loaded with other goods and
-dispatched outwards, or may be taken away empty if the loading-bank is
-reserved for arriving goods only. Where the traffic is large and
-constant there is an advantage in having separate goods-sheds for the
-inwards and outwards work.
-
-The following diagram sketches will illustrate some of the many types
-of goods-sheds in use on railways:--
-
-Fig. 421 shows a shed suitable for general merchandise at a small
-roadside station. For economy of construction, the line of rails and
-cartway are both placed outside the building. A small goods-office is
-built at one end, in which is fixed the pedestal and lever indicator
-of the cart-weighing machine. The roof is projected outwards over the
-doorways for the railway trucks and for carts. The railway truck
-doorways are spaced to correspond to the length of the trucks. A
-narrow platform, about 3 feet wide, is formed outside the shed
-alongside the trucks for the convenience of the men when loading or
-unloading.
-
-Fig. 422 represents a rather larger shed, with the line of rails
-inside the building and cartway outside. With this type the railway
-trucks are entirely under cover, and can be unloaded or loaded more
-conveniently. It has also the additional advantage that the trucks and
-their contents can be left secure when the shed is locked up at
-closing time.
-
-Fig. 423 shows a shed with a line of rails down the centre, and a         279
-loading-bank on each side, the cartways being outside the building;
-one loading-bank is for inwards goods, and the other for outwards
-goods. On the arrival of a loaded railway truck, the door on one side
-is opened, and the contents unloaded on to one of the loading-banks.
-The door is then closed, and the opposite door opened for loading from
-the other loading-bank. By this method a railway truck can be unloaded
-and loaded again without changing its position.
-
-Fig. 424 represents a shed with two lines of rails down the centre and
-loading-banks on each side, the cartways being outside the building.
-One line of rails and corresponding loading-bank is for inwards goods,
-and the other line of rails and loading-bank for outwards goods. When
-the railway trucks on the arriving line are unloaded, they are either
-drawn out of the shed and shunted on to the opposite line to be loaded
-again, or transferred direct on to the opposite line by turn-tables,
-or traversers, placed at convenient distances between the columns
-supporting the roof.
-
-Fig. 425 illustrates a shed in which both the line of rails and
-cartway are placed inside the building. This is no doubt the most
-convenient type for transfer of general goods, as all the operations
-of transhipment are carried on entirely under cover; but it is the
-most costly, on account of the large building and roof area required.
-
-Fig. 426 shows a large double shed similar in general arrangement to
-the type represented in Fig. 425, but with three lines of rails down
-the centre. The line A may be used for inwards goods, and C for
-outwards. By means of turn-tables, or traversers, connecting the three
-lines at convenient distances in the length of the building, the
-unloaded trucks can be transferred on to the far line, C, for
-loading again, or on to the line B, to be drawn away out of the
-building. The lines A and C may both be used for inwards traffic,
-or both for outwards, and the line B used for taking away or
-bringing in empty trucks.
-
-Fig. 427 represents a shed with the line of rails and cartway inside the
-building, and both very nearly on the same level. This class of shed is
-often considered the most suitable for fruit, vegetables, and certain
-light goods which require prompt delivery and careful handling.
-
-Fig. 428 shows a form of shed with a raised loading-bank on one side      280
-of a line of rails, and a cartway on the other. With this arrangement
-the railway trucks may be loaded or unloaded, either from the raised
-loading-bank or direct from carts and drays drawn up alongside the
-trucks, according to the description of merchandise presented.
-
-Fig. 429 shows a type of umbrella roof sometimes erected over a narrow
-loading-bank outside of a goods-shed. It is simple and economical in
-construction, and provides good accommodation for loading and
-unloading under cover packages and goods of secondary importance.
-
-The above sketches illustrate some of the many arrangements for
-goods-sheds, and can be modified and extended in several ways. The
-leading dimensions, widths of loading-banks, cartways, and gauge of
-lines, will have to be adjusted to suit circumstances.
-
-Looking at a goods-shed merely as a medium for the convenient transfer
-of merchandise between the railway and the roadway, the inference is
-soon drawn that the removal of the goods into trucks or carts should
-be effected as speedily as possible, otherwise a large extent of
-shed-room will be required for carrying on a moderate amount of work.
-Every effort should be made to clear the goods from the loading-bank
-as soon as they have been properly unloaded and checked. Any laxity in
-this respect will cause an outcry for increased accommodation, which a
-little more energy and careful organization would have prevented.
-
-Timber plank floors are generally preferred for inside loading-banks.
-Inside cartways should be formed either of granite setts or
-wooden-block paving; the latter is better, being less noisy, and, if
-occasionally sprinkled with sand, will afford a good foothold for the
-horses. A macadamized roadway under cover is never satisfactory, as it
-is always dry, and never binds together into a compact even surface.
-Sliding or rolling doors are the best for goods-sheds, as they are
-more out of the way, and under better control during high winds.
-
-Cranes of appropriate strengths, and worked by hand or other
-motive-power, should be distributed in suitable positions throughout
-the shed. They should be placed so that they can, when required, lift
-direct out of a railway truck on the one side, and deposit into a cart
-or dray on the opposite side of the loading-bank.
-
-Goods-sheds may be built of stone, brick, iron, or timber, or a           281
-combination of all of them. Where the requirements are well proved,
-and the traffic certain, it is better to build a substantial permanent
-structure. Iron sheds, with sides and roofs of galvanized corrugated
-iron sheets, will last for many years if not made of too light
-materials. There are many cases where it is more prudent to put up a
-goods-shed in timber than to incur the cost of one of more permanent
-character. Where the traffic is uncertain, or the foundations bad, or
-out in undeveloped districts abroad, a building of timber will serve
-the purpose for a number of years, or until the period of probation
-has passed, and the actual requirements are accurately ascertained. In
-a timber-built shed, the decay usually commences about the ground
-line, but if the nature of the soil will permit of the construction of
-a small dwarf foundation wall of masonry or concrete up to about nine
-inches above the ground line, the life of the building will be
-prolonged for several years.
-
-The best method of admitting daylight into a goods-shed is from the
-roof, and a liberal extent of roof-glazing should be provided for the
-full length of the building, and so distributed as to be well over the
-loading-banks. In tropical countries the amount of roof light must be
-reduced, on account of the great glare from the sunlight.
-
-An ample supply of artificial light will be necessary when working
-after dark or during the night. In some instances the goods-sheds in
-large and important business centres have one or more upper storys, in
-which goods are warehoused pending the owners’ instructions, the goods
-being transferred between the loading-banks and upper floors by lifts
-or cranes.
-
-A proper supply of weighing machines for carts, drays, railway trucks,
-and packages on the loading-banks will be necessary to facilitate the
-checking of the goods.
-
-There is always a large proportion of traffic which can be dealt with
-outside the goods-sheds, either on loading-banks or cartways alongside
-the sidings. Outside loading-banks should be of good width, with
-approach roads of easy gradient. In tropical countries a light shed,
-open on all sides, is frequently erected over a portion of these
-outside banks, to protect the goods and workmen from the heat of the
-sun. Fixed cranes or travelling cranes will be required for lifting
-the large packages, heavy castings, and logs of timber. Where there is
-a large cattle traffic, separate sidings, loading-banks, and approach     282
-roads should be set apart for the purpose, with suitable water-troughs
-and cleansing appliances. Horses can be unloaded at any loading-bank,
-but for the more valuable class of animals and for carriages it is
-usual to construct a special horse and carriage dock, as shown in Fig.
-430, the carriages being wheeled off the end of the carriage truck, as
-indicated in the section. Cartways alongside the sidings are very
-convenient for unloading coals, stone, bricks, sand, lime, and many
-other materials which have to be passed out of the trucks in small
-quantities at a time. To encourage and facilitate traffic at roadside
-stations, traders are frequently allowed to stack or store large
-supplies of some of the above materials on ground set apart for the
-purpose near some convenient siding, the stock being disposed of in
-detail to suit the local requirements. Coal-drops are sometimes
-adopted where there is a large trade in that commodity. They are
-constructed by carrying the line of rails on strong balks of timber or
-small girders placed across the top of walled-in coal-yards or divided
-areas. The coal is thrown out of the trucks, and falls a depth of 15
-or 20 feet into the yard below. In consequence of the height from
-rail-level to ground a large tonnage can be piled up, and stored in a
-small area, and the unloading of the trucks effected very rapidly,
-particularly so where special trucks with opening floors or hinged
-bottoms are used for the purpose. In many cases capacious roofed-in
-sheds are built for storing coals, lime, cement, grain, or other
-materials liable to deterioration from the weather. These sheds are
-built alongside a siding; the contents of the trucks are unloaded or
-thrown into the sheds through doors spaced to correspond to the
-railway-truck doors, and are carted away through doorways on the
-opposite side.
-
-It is customary to place _buffer-stops_ of some form at the
-termination of dead-end sidings in a station, to bring to a stand such
-carriages or waggons as may be approaching with too much speed to be
-stopped without the interposition of some substantial barrier.
-
-Figs. 430, 431, 432, and 433 are sketches of some of the many kinds of
-buffer-stops, and will explain themselves. In Fig. 430 the buffer-stop
-is made of flange rails, and is shown as fitted in a carriage-dock
-with wrought-iron plate landing, A, and plate-iron hinged flaps,
-B, B. The latter are turned over, and rest on the floor of the
-carriage-truck, to form a pathway when taking on or off a vehicle.
-
-[Illustration: Fig. 430, 431, 432, 433]
-
-Fig. 431 shows a buffer-stop made of double-head or bull-head rails;      284
-and Fig. 432 is a buffer-stop made of heavy timbers.
-
-Fig. 433 shows a very simple buffer-stop frequently adopted for
-sidings where there is not much traffic. It is made of good old
-sleepers bound together with old double-head rails, and the interior
-filled with earth or clay.
-
-In addition to the buildings alluded to in the foregoing description,
-the engineer has to design and construct very many others in
-connection with railways. These will include large running-sheds for
-stabling working locomotives; sheds for housing carriages; workshops
-for building and repairing engines, carriages, and waggons; foundries;
-large stores for materials; offices; dwelling-houses; mess-rooms,
-etc.; many of them involving questions of difficult foundations, and
-nearly all of them requiring special strength and stability to meet
-the heavy weights and vibrations to which they are subjected.
-
-
-
-
-  CHAPTER V.                                                              285
-
-  Sorting-sidings--Turn-tables--Traversers--Water-Tanks and
-  Water-Columns.
-
-
-Sorting-sidings.--On many important long main lines it is necessary
-to establish special independent sidings for sorting or arranging
-waggons of merchandise and minerals. Where there are only two lines of
-rails to serve for the UP and DOWN service of a heavy passenger and
-goods traffic, it is imperative to restrict those lines as much as
-possible to the actual transit of trains, and not to block them by
-unnecessary occupation for shunting purposes. A goods train running a
-long distance collects waggons from many roadside stations, and at
-some of them several waggons will be taken on, to be forwarded to
-various and widely distant destinations. The accumulated train
-comprises waggons which must be divided out into groups, to be passed
-on either to distant sections of the same railway system, or on to
-neighbouring lines. To avoid interruption to the train-working, and
-the delay of complicated shunting operations at the roadside stations,
-the waggons are attached just as they are dicked up, and the work of
-sorting is allowed to stand over until the train arrives at the place
-assigned for the purpose. A site for sorting-sidings is generally
-selected where the ground and gradient are favourable, and where ample
-room can be obtained for a large number of short parallel lines, with
-space for future extensions. The arrangement that naturally suggests
-itself is that of a series of fan-shaped sidings leading out of main
-shunting lines, separate from the main-traffic lines. In some cases
-the sorting-sidings are laid down with dead-ends, as in Fig. 434, and
-in others they are made as through sidings, connecting at both ends
-with shunting lines and main-traffic lines, as in Fig. 435. Each of
-the sidings is usually made sufficiently long to hold a complete train
-of sorted waggons, and the number of them will depend upon the number     287
-of sections to be served, and the amount of waggons to be sorted.
-Sometimes the sidings are laid with a slight falling gradient leading
-away from the main shunting lines, to facilitate the running out of
-the waggons into the respective sidings.
-
-[Illustration: Fig. 434, 435]
-
-An arriving goods train is first drawn out of the main-traffic lines
-into one of the shunting lines, and then handed over to the staff of
-men in charge of the sorting operations, who at once mark the waggons
-according to the number or designation of the particular siding into
-which they have to be placed. A suitable engine is generally set apart
-for this work, and in a very short time the entire train is divided
-out by one or more waggons at a time, and distributed into the various
-sidings, representing different sections of the line, or groups to be
-handed over to neighbouring railways. When one of these sorting-sidings
-contains a full complement of waggons, an engine is attached, and the
-train despatched to its destination, leaving the siding clear for
-another set of waggons. Where the trains to be sorted are very
-numerous, two or more shunting-engines may be engaged working at the
-same time on distinct sets of shunting lines and sidings. Sometimes it
-may be expedient to have one lot of sorting-sidings leading off the UP
-line, and another lot leading off the DOWN line, to meet the
-requirements of trains coming and going in both directions. With
-sidings well laid out, and fitted with ample facilities, a
-well-organized staff can carry out a very large amount of work both
-expeditiously and economically. There are several of these
-sorting-sidings stations in operation, where from one thousand to two
-thousand waggons are sorted and marshalled into trains every
-twenty-four hours.
-
-The above diagram sketches merely illustrate the general principle of
-the sorting-sidings, and may be modified and enlarged in many ways to
-suit the traffic requirements and local surroundings.
-
-
-Turn-tables.--Turn-tables revolving on fixed centres are made of
-various sizes according to their use for engines, carriages, or
-waggons. The carrying-beams may be made of cast-iron, wrought-iron, or
-steel, but the latter material is the most suitable for tables of more
-than 20 feet diameter. For small turn-tables, cast-iron beams will
-serve very well, for although more liable to fracture, they will not
-suffer so much from rust and oxidization as wrought-iron or steel.288
-
-[Illustration: Fig. 436, 437, 438, 439, 440]
-
-Opinions as to the most convenient position and use of turn-tables        289
-have undergone a considerable modification during the past twenty or
-twenty-five years. Circular and semi-circular running-sheds for
-engines, as in Figs. 436 and 437, are not so often adopted now as
-formerly. Although compact and accessible in theory, they possess the
-one great drawback that when the turn-table in the centre becomes
-deranged by wear or accident, none of the engines on the
-standing-lines inside the building can be taken out until the
-turn-table is again put into working order. A stock of from twenty to
-thirty engines might thus be put entirely out of the service for a day
-or more. This objection is considered to be of so serious a nature
-that running-sheds are now almost always constructed of rectangular
-form, of which Fig. 438 is a type.
-
-With this description of shed, the lines of rails are laid down
-parallel to one another, and the engine turn-table is placed on a line
-separate and distinct from those lines forming connections with the
-shed.
-
-Where there is a large goods traffic, an endeavour is generally made
-to so lay down the goods-sheds and approach lines and sidings, that
-the full complement of waggons may be shunted in or out of the shed at
-one operation. This arrangement, which dispenses with turn-tables
-altogether, admits of the ready removal of a central or far-end
-waggon, without the necessity of taking out so many others in front
-one by one over the turn-table. At the same time, there are large
-numbers of these waggon turn-tables in use, and there are many cases
-where access to side sheds or detached stores can only be obtained by
-turn-tables.
-
-A goods-shed and lines laid down with turn-tables, as in Fig. 439,
-will always be more tedious and costly to work than one laid down with
-direct through lines, as in Fig. 440. Should either of the turn-tables
-shown on Fig. 439 get out of order and become incapable of turning,
-then the entire side of the shed controlled by that table will be
-rendered useless until the defect be remedied.
-
-Engine turn-tables are rarely made with more than one road on the top.
-The most modern types generally consist of two strong wrought-iron or
-steel-plate girders well braced together and securely attached to a
-middle framework which rests on and revolves round a centre-piece
-fixed on a solid foundation To the ends of the girders are attached       290
-large roller wheels which travel round a solid iron or steel
-roller-path laid down along the circumference. These modern
-turn-tables are generally worked on the balancing principle, by
-bringing the engine and tender to a stand in such a position on the
-rails that the greater portion of the weight is thrown on to the
-cup-shaped steel centre, so that a small force applied to the long
-outrigged hand-levers at the ends is sufficient to turn one of the
-heaviest locomotives. Figs. 441 and 442 give sketch plan and section
-of one of these steel-plate girder turn-tables, which has few parts,
-and very little to get out of order. The end rollers guide the table
-when making any portion of a revolution, and carry such part of the
-weight as may not be taken up by the centre. A recess is shown in side
-wall to facilitate the inspection of end rollers. In the earlier forms
-of engine turn-tables, the revolving movement was effected by
-attaching to the upper portion of the girders a strong winch, which
-acted upon gearing fixed either to the end rollers, or direct on to a
-toothed ring forming part of the roller-path. In cases where the
-engine turn-table was in constant use, as in connection with a large
-running-shed, the winch was sometimes driven by a small steam-engine
-to expedite the movement.
-
-The great increase in the lengths and weights of modern locomotives
-has necessitated the removal of many of the old small turn-tables, and
-replacing them with others of 45 or 50 feet, or more, in diameter.
-
-[Illustration: Fig. 441, 442, 443, 444, 445]
-
-An engine turn-table is a costly item in railway requirements, not
-only in the girder-work, but in the large amount of building in the
-side walls and centre pier, and an effort is always made to avoid the
-outlay unless the table can be placed where it may be of permanent
-use. In the construction of foreign railways, and in our colonies,
-where the lines are opened in sections as the work goes forward, the
-temporary arrangement shown in Fig. 443 is frequently used instead of
-an engine turn-table. The sketch will almost explain itself. On the
-main line, A, B, C, D, switches are placed at B and C, from which turn
-out curved lines, uniting at the switches E. An engine proceeding from
-A, and passing round the curve B, E, G, then round curve G, E, C, and
-back along main line, D, C, B, A, will be turned round as efficiently
-as on a turn-table. The writer has used this arrangement abroad with
-great advantage. It involves very little work or expense beyond laying
-down the permanent way, and so soon as the temporary terminus of the      292
-line has been advanced further ahead, the rails and sleepers can be
-lifted and used again elsewhere.
-
-Figs. 444 and 445 give sketch plan and section of a waggon turn-table
-which has been largely adopted. The centre should be securely fixed on
-a solid foundation of masonry, brickwork, or concrete. The deep outer
-cast-iron ring is made in segments, properly fitted and bolted
-together, and fastened down to the foundation course. The stop-checks
-are cast on to this outer ring. Two roads, at right angles to each
-other, are laid on the turn-table, so that waggons to or from the
-goods-shed have only to make one quarter turn of the table. The top is
-generally covered with either chequered iron plates or timber to give
-good foothold for the men and horses which have to pass over in moving
-the waggons. If properly balanced, the table is easily turned by men
-pushing at the opposite corners of the waggon, or by a horse and
-tail-rope, or by hydraulic power through a capstan. In many cases of
-bad or soft foundations these small turn-tables are erected on a
-strong framework of creosoted timber.
-
-Carriage turn-tables are now very rarely used. With the old short
-four-wheeled carriages the moderate-size turn-table was convenient for
-transferring an extra carriage to or from a spare carriage-line
-alongside the making-up train at a platform, but modern carriages are
-now so much longer, some of them twice the length, or more, than
-formerly, that nothing less than an engine turn-table would be large
-enough for them. Sometimes a carriage traverser is used for this
-station work, but much more frequently these long carriages are
-shunted on or off the making-up train by simply running them in or out
-through the nearest switches and cross-over road.
-
-[Illustration: Fig. 446, 447]
-
-Fig. 446 is a sketch of a carriage-traverser, of length to suit an
-ordinary six-wheeled carriage. The length, however, may be extended to
-take on a bogie carriage or any other long carriage. The framing is
-made of wrought-iron or steel, well braced together. The carrying
-wheels, W, W, run upon rails laid at right angles to the
-running-line or siding, and the carriage is moved on to or off the
-traverser by means of the hinged ramps shown at R, R. A carriage,
-once on the traverser, may be moved across one or several lines of
-running road, according to the extent of traverser line laid down; and
-this appliance is very suitable for large terminal stations and
-carriage-repair shops. It will be observed that the operations of the     294
-turn-table and the traverser are quite distinct. With the former a
-vehicle can be transferred from one line to another, and also turned
-completely round; but with the traverser the vehicles are simply moved
-in a parallel direction, from one line to another, and when it is
-necessary to turn or change a vehicle end for end, as in the case of a
-mail-bag-catching apparatus van or a special saloon, then resort must
-be had to a turn-table.
-
-
-Cranes.--A large portion of the merchandise conveyed on railways
-must be lifted into or out of the trucks by cranes. The position,
-description, and capacity of these will depend upon the materials to
-be handled. Large slow-working powerful cranes will be necessary for
-raising heavy castings, large logs of timber, or massive blocks of
-stone; while the small quick-acting cranes will be more suitable for
-dealing with the lighter packages, casks, and bales.
-
-Fig. 447 shows a gantry or overhead crane, used for lifting heavy
-weights out of an ordinary road-waggon, carrying them a short
-distance, and then depositing them in a railway truck, or _vice
-versâ_. Double-flanged rollers, attached to the ends of the platform
-C, C, run upon the rails R, R, which are fixed on
-the top of the beams B, B, secured to the verticals A, A.
-The working length of the gantry is only limited by the number of the
-verticals, and this, being the fixed portion of the work, may be
-extended out to any distance required. The travelling or carrying
-girders of the platform C, C may be made of wrought-iron, steel,
-or timber. They must be strongly framed and braced together as a
-platform to carry the lifting machinery and weight lifted, and have
-convenient gearing for effecting the transverse or side-to-side
-movement, as well as a horizontal movement along the line of rails on
-top of the verticals. Where the fixed portion of the gantry is of
-considerable length, two or more travelling platforms can be used. In
-the sketch given above, the entire gantry is shown as made of timber,
-but iron or steel can be equally well adopted, and continuous masonry
-or brickwork walls may be built to serve as verticals.
-
-[Illustration: Fig. 448, 449, 450]
-
-Fig. 448 is a sketch of a small handy crane for warehouse work; it is
-quick in action, and restricted to weights not exceeding twelve
-hundredweight. This form of crane may be strengthened to lift still
-greater loads, but in doing so the additional size of the parts, and
-the corresponding extra labour in working, detract from its efficiency    296
-as a quick-acting crane for light weights.
-
-Fig. 449 shows an ordinary fixed three-ton jib crane, a very
-convenient size for general station work. The centre pillar is fixed
-into a bed of masonry or a solid block of concrete. The jib is of
-wrought-iron or steel, those materials being so much more reliable
-than timber, and very little more expensive. This crane must be fixed
-so that in one direction the jib may command the centre of a railway
-truck, while in the other it can conveniently raise the packages to or
-from the carts or loading-bank alongside. In the sketch the crane is
-shown as placed on the loading-bank, but it may be placed on the same
-level as the rails if preferred. Cranes of this type and strength are
-frequently found necessary for the inside work of goods-sheds, where
-packages of considerable weight have to be handled. A very similar
-class of jib-crane is constantly made for lifting weights of five or
-ten tons or more, the different parts being made stronger and heavier
-to correspond to the weights to be raised.
-
-Fig. 450 shows a five-ton travelling crane. Although more costly, it
-has the advantage over a fixed crane that it can be moved about from
-place to place. It is mounted on a very strong waggon framework, and
-provided with springs and spring buffers. Instead of moving round a
-long deep centre, the jib of the travelling-crane is arranged to work
-round a bevelled metal roller-path laid down on the platform of the
-waggon, and has a heavy counterweight loaded to correspond to its
-capacity. Before commencing to lift any weight strong oak blocks or
-filling pieces are inserted between the tops of the axle-boxes and the
-under side of main beams of waggon, to relieve the springs of the
-pressure which would arise from the weight lifted. From the four
-corners of the waggon are suspended chains carrying gripping-hooks to
-be attached or clipped round the rails. These gripping-hooks, when
-firmly secured to the rails, prevent the crane from tilting over, as
-the weight of the waggon and also of the rails and sleepers are
-brought into play to counteract any tendency to throw the crane off
-its proper balance. With the larger size travelling cranes, capable of
-lifting ten or fifteen tons or more, outriggers of joist or
-I-iron, moving in slides, are run out at right angles on either
-side, and can be loaded with bars of iron or other weights to form a
-counterpoise.
-
-A medium-sized travelling-crane is a most useful appliance about a        297
-railway station; it has a much greater range of utility than a fixed
-crane, but it is not always appreciated as it should be. It merely
-requires a line of rails laid down parallel to the rails of siding,
-and may be placed either on the same level as the siding, or on the
-level of the loading-bank. Being laid flush with the roadway, the
-rails do not present any obstacle to the passage of carts or movement
-of merchandise. As one waggon on the siding is loaded or unloaded, the
-crane can be moved along its own line of rails, and be put to work at
-another without the necessity of moving or drawing out any of the
-railway waggons on the siding. Five, ten, or twenty, or more railway
-waggons can be dealt with in this way, according to the length of
-crane-line laid down. The crane can also be readily removed to another
-part of the station-yard, or to another station along the line. For
-stations with an intermittent or spasmodic traffic in heavy timber,
-large blocks of stone, or other unwieldy articles, a travelling-crane
-is particularly suitable, as it will meet all the wants so far as the
-lifting is concerned, and when the rush of traffic is over, it can be
-easily transferred to some other sphere of usefulness. The
-crane-siding itself is never very costly, as the rails are generally
-old rails taken out of the main line, and laid on good second-hand
-sleepers. They have little to do, and merely form a track for the
-moving crane.
-
-Fig. 451 is a sketch of an ordinary Goliath crane constructed of
-timber. The general arrangement and capabilities of this crane are
-somewhat similar to those of the gantry shown in Fig. 447. Both of
-them are designed to lift heavy weights, and move them sideways into,
-or out of, ordinary road waggons, but the methods of application are
-different. In the gantry the verticals are permanently fixed, whereas
-in the Goliath the verticals and overhead girders are all attached and
-braced together, forming a complete framework which is carried by
-double flanged rollers running on the lines of rails R, R. The
-winches or gearing for lifting the weights, or slinging them sideways,
-or for propelling the crane forward on the rails, are attached to the
-verticals as shown, and are worked from the ground-level instead of
-the overhead platform, as indicated in the gantry. As each Goliath
-crane is complete in itself, there is nothing to prevent two or three
-of them working at the same time on a long length of crane-line.
-
-[Illustration: Fig. 451, 452]
-
-Fig. 452 shows an ordinary derrick crane, which, on account of the        299
-large and varying sweep of the jib, is found very convenient for
-certain classes of work. It occupies a considerable amount of room,
-and its adoption is therefore limited to situations where space is of
-secondary importance.
-
-All the cranes described above are shown as worked by hand-power, but
-they may be worked by steam, hydraulic machinery, or electricity.
-Manual power will be the most economical where the use of a crane is
-only occasional, but it would be too slow and costly where there is
-constant heavy work.
-
-
-Water-tanks.--A supply of good water forms an important item in
-railway working, and ample provision must be made at all principal
-stations for the requirements of engines and general station purposes.
-According to the locality, the water may either be procured from the
-main of some established waterworks company, or be pumped from a well,
-or forced up from a stream by a ram, or brought down by gravitation in
-pipes from a spring or stream at a distance. Water thus obtained is
-conducted into tanks placed at a height of 18 or 20 feet, or more,
-above the level of the rails, and forms a storage supply from which
-deliveries can be made at a fair pressure and in large volume. The
-tanks may be made of cast-iron, wrought-iron, or steel, or even of
-wood. In the great timber-producing countries abroad, water-tanks,
-some of them of large capacity, are very frequently made of wood, the
-circular or half-cask form being preferred; but at home, and on
-European lines generally, wooden tanks are rarely used except for
-temporary purposes. Cast-iron being less liable to deterioration from
-rust than wrought-iron or steel, is much used for water-tanks.
-
-[Illustration: Fig. 453, 454, 457, 455, 456, 461, 460, 459, 462, 463,
-464, 458]
-
-Figs. 453 to 457 are sketches of a medium-sized cast-iron water-tank,
-to hold about 7800 gallons. The size may be varied both in length,
-width, and depth, without in any great measure altering the type. The
-lower portion, or tank-house, may be of stone, brick, wood, or iron
-framework, and may be utilized as a pump-room, store, or lamp-room. In
-the sketch given a row of cast-iron girders are placed across the top
-of the walls of the tank-house, to carry the tank, the plate-joints of
-the latter being made to coincide with the centre lines of the
-girders. The lower and upper edges of the tank-plates are shown curved
-in section, the former for appearance and facility of cleaning, and
-the latter to check the tendency of the water rippling or splashing       301
-over the sides when disturbed during high winds. The large pipe, A,
-is securely bolted at the bottom of the tank, and forms a shield or
-funnel through which the supply pipe, B, passes upwards into the
-tank. C is an overflow, or waste pipe, to carry away any surplus
-which may find its way into the tank after the water has risen to its
-fixed maximum height. All the contact surfaces of the cast-iron
-tank-plates must be accurately chipped or planed, and fitted to ensure
-water-tight joints. Stay-rods must be placed at frequent intervals,
-connecting the vertical or outer plates to the horizontal or floor
-plates. When required to hold more than 20,000 gallons, it is better
-to make the tank in two parts, by placing a permanent plate partition
-across the middle, in reality making two separate tanks, which can be
-connected or disconnected at will. The double tank arrangement gives
-additional strength, and possesses the advantage that the one tank can
-be emptied and cleaned out while the other remains in service.
-
-Water-tanks constructed of wrought-iron or steel plates are usually
-made circular in form, with vertical sides. The floor-plates must be
-either carried on small girders, as in the cast-iron tank, or be
-strengthened internally with angle-irons, tee-irons, and tie-rods. The
-rivetting must be well done, all joints sound and watertight. This
-class of tank must be kept well painted, or oxidization will take
-place very rapidly. The arrangement of inlet, waste-pipe, and delivery
-pipe may be the same as for the cast-iron tank. Although frequently
-seen abroad, these circular wrought-iron tanks are not often adopted
-at home. By many the appearance of the circular tank is considered
-inferior to one of neat rectangular shape, and the form of the round
-tower does not lend itself so conveniently for use as a pump-room or
-store.
-
-There may be no practical difficulty in constructing a large circular
-wooden vat or water-tank, but there cannot be any great actual
-economy, except in those countries where suitable timber is very
-cheap, and iron very dear. The wooden tank must be made of selected
-materials, and by skilled workmen; but however carefully constructed
-it cannot be expected to last so long as an iron tank. In many parts
-of the United States of America there are excellent examples of the
-circular wooden tank, strongly put together, and covered with a light
-ornamental roof. Numbers of these wooden tanks have been erected there
-in places where the cost of carriage alone of an iron tank would have
-been a serious item, and where suitable timber was fortunately            302
-close at hand.
-
-In cases where engines are watered direct from a water-tank, a simple
-delivery-valve, as shown in the sketch (Fig. 458), will answer the
-purpose. This valve has to be pulled open by the chain and lever,
-D, and when released falls with its own weight, and is kept closed
-by the pressure of the water above. The delivery-pipe should not be
-less than 7 or 8 inches in diameter, to accelerate the filling of the
-tenders. Where water has to be delivered to engines at two or more
-places in a station-yard, and the supply derived from the same
-principal tank, the result may be obtained either by laying down 7 or
-8-inch main pipes from the principal tank to separate water-columns,
-or by erecting two or more pedestal water-tanks, similar to Figs. 459
-to 462, each of which holds a little more than the average quantity
-for one tender, and can be fed from the principal tank by a
-comparatively small pipe of 3 or 4 inches in diameter. It is simply a
-question of expense--whether it is cheaper to lay down a long length
-of 7 or 8-inch main pipe and ordinary water-columns, or to adopt the
-small pipes and pedestal tanks.
-
-Figs. 459 to 462 are sketches of a medium-sized pedestal water-tank to
-hold 1200 gallons. The supporting column must have a very wide base,
-bolted down to a solid foundation. The tank itself, made circular in
-plan, is generally constructed of light plates of wrought-iron or
-steel, the lower portion or floor of tank being very securely attached
-to the vertical column. Notwithstanding their top-heavy appearance,
-these pedestal tanks can be made very firm and steady if enough width
-be given to the base-plate, and the tank properly fixed to the column.
-Water is led into these pedestal tanks by a small pipe passing up
-inside the supporting column, and the delivery may be effected by a
-simple valve, as explained for Fig. 458.
-
-Fig 463 shows one type of water column for watering engines. The wide
-base-plate is bolted down on to a foundation of stonework, brickwork,
-or concrete, and the main supply pipe (not less than 7 or 8 inches in
-diameter) is carried up inside the column, and connected with the
-screw valve, A, which regulates the delivery to the tenders. The
-curved top, which forms the outlet, and carries a leather hose, works
-on a swivel joint, and can be swung round, either to the right or
-left, for convenience of supplying engines on one or two
-standing-lines. The delivery valve can be opened or closed by the         303
-small hand-wheel B, which is conveniently accessible to the man on
-the tender. On the above sketch (Fig. 463) the water column is shown
-placed at an ordinary normal distance from the rails; but in cases
-where there is considerable space between the two lines of rails, or
-where a platform intervenes, the swinging arm may be extended out to
-the necessary length, and counterbalanced as shown in Fig. 464.
-
-
-
-
-  CHAPTER VI.                                                             304
-
-  Comparative Weights of some Types of Modern Locomotives.
-
-
-Weights of Locomotive Engines.--The demand for higher speeds of
-passenger trains, with more conveniences, luxuries, and consequent
-increased weights in the carriages, has naturally led to greatly
-increased power and weight of the locomotives devoted to the passenger
-service. Although these engine weights have so largely increased
-during the past twenty-five years, there is nothing to indicate that
-they have yet reached the maximum. The tendency is still to increase,
-and will doubtless continue, so long as the permanent way can be made
-to sustain such enormous rolling loads. Locomotives for goods trains
-have also increased in power and size, but perhaps not in the same
-proportion as those for the passenger service. There is not the same
-disposition to expedite the transit of goods and minerals, which do
-not deteriorate during a long journey. Perishable articles, such as
-fish, fruit, and milk, are usually conveyed by passenger trains, or
-trains set apart specially for the purpose.
-
-[Illustration: Fig. 465, 466, 467]
-
-The heavier engine doubtless possesses greater tractive power, but
-apart from the question of tractive power is the all-important one of
-steadiness and safety on the rails. A locomotive passing round a
-curve, even at a moderate velocity, produces disturbances in
-proportion to the capability of the machine to adapt itself to the
-altered position, and if both the engine and permanent way are
-constructed so as to be almost unyielding, then destructive wear and
-tear and increased risk of derailment must ensue. The adoption of the
-four-wheel bogie truck to the locomotives on our home and continental
-lines--although very slow in coming--has contributed greatly to their
-improvement, enabling the weight to be distributed over a longer, yet
-more flexible wheel-base, affording greater facility and comparative
-safety in traversing curves; and rolling, or passing over the rails,      306
-with as little injurious effect to them as possible. It is strange to
-find that the four-wheel bogie truck, originally designed in England
-in the early days of the railway era, should for so long have met with
-so little favour on this side of the Atlantic. The Americans, at all
-times prompt to recognize any appropriate mechanical arrangement,
-adopted the bogie truck upon its first introduction into the States.
-They have worked out many improvements in the details, and upon the
-thousands of locomotives on their vast network of railways, the bogie
-truck, in one form or another, has been universally adopted from the
-beginning.
-
-On our home and continental lines, the modern express locomotive, with
-a four-wheel bogie truck in front, is a much longer vehicle than its
-predecessors, and its total weight is distributed over a greater
-wheel-base; but the actual weight placed upon the driving-wheels, or
-on the coupled wheels, is now very much in excess of former practice,
-and must be taken into consideration when working out the details of
-girders and cross-girders of under-line bridges. Numbers of girder
-bridges have had to be taken down and replaced with stronger
-structures, not for reasons of wear or decay, but simply because they
-were incapable of carrying with safety the modern heavy rolling loads.
-Present experience points out the expediency of providing in all new
-under-line bridges a liberal margin of strength to meet future
-developments.
-
-Figs. 465 to 479 are diagram sketches of a few modern types of
-locomotives, giving leading dimensions and weights, and may be found
-useful for reference when working out the necessary strengths of the
-various portions of bridge-work. Upon comparing some of the principal
-particulars with those of the earlier class, it will be noted that in
-many of the modern types the piston area has been doubled, the
-boiler-pressure doubled, and the weight of the engine doubled also.
-
-The engines shown in Figs. 465 and 467 have great weights placed on
-the single driving-wheels, and should only be used where there is a
-very strong permanent way. With the four-wheel coupled engines, the
-weight for adhesion can be distributed between the driving and
-trailing wheels.
-
-[Illustration: Fig. 468, 469, 470]
-
-[Illustration: Fig. 471, 472, 473]
-
-Fig. 473 represents a very excellent type of American engine which has
-been extensively adopted in the United States for many years. The six
-coupled wheels distribute the weight over a fairly long wheel-base,       309
-retaining their united weight for adhesion. The four-wheel bogie truck
-in front forms a valuable path-finder to the engine, both for passing
-round curves or on straight line. This class of engine is very
-serviceable for various kinds of traffic, and is particularly suitable
-for lines where the rails and fastenings are comparatively light. In
-the example shown, the flanges are turned off the centre pair of
-coupled wheels; but for lines where the curves are of small radius,
-the flanges may be turned off the leading pair of coupled wheels,
-instead of the centre pair, to reduce the length of rigid wheel-base.
-This type of engine has latterly been introduced on various European
-and foreign railways, and recently on the Highland Railway of
-Scotland, as shown in Fig. 470. The writer has had engines of this
-class under his charge abroad, and found them to be most useful for
-heavy passenger and goods-train service. They run very steadily, are
-easy on the permanent way, and light in repairs. As they become better
-known they will be more appreciated, and will doubtless before long
-supersede in many cases the rigid six-wheel-coupled goods engine. The
-principal objection of any importance that can be raised against them
-is that on many lines the present engine turn-tables are too small for
-such long engines; but it would be far more economical in the long run
-to enlarge a few turn-tables than to continue the adoption of rigid
-engines which from their form and arrangement tend to unnecessary wear
-to themselves and the permanent way.
-
-[Illustration: Fig. 474, 475, 476]
-
-[Illustration: Fig. 477, 478, 479]
-
-Fig. 476 shows an average sample of the ordinary six-wheel-coupled
-goods engine in use on so many of our home railways. Where the curves
-are easy and the permanent way strong, the drawback of the long rigid
-wheel-base may not be so apparent; but for a line abounding in sharp
-curves, perhaps no more destructive machine could possibly be devised
-than the ordinary six-wheel-coupled goods engine. Without any
-flexibility, forced along with great power, and too often driven at
-unnecessary high speeds, engines of this type have too small a margin
-of safety when traversing the curved portions of the road. A slight
-unevenness in the rails, or a sharp flange on the wheel may supply all
-that is wanting to cause the engine to leave the track, and the
-probability that such risks are more common than is supposed, is far
-from satisfactory. The great weight of the engine doubtless tends to
-keep it on the track, but the rapid wear of the tyres, and of the         312
-inside of the rail-heads clearly demonstrate the enormous amount of
-friction and abrasion that takes place.
-
-Fig. 477 represents a type of eight-wheel-coupled engine designed for
-hauling passenger or goods trains over long lengths of heavy mountain
-inclines. The engine is a large one in every way, and of great total
-weight, but the weight is distributed over a long wheel-base and
-without imposing a greater tonnage per pair of wheels than is done in
-some of the smaller and less powerful engines. The flanges are turned
-off the leading pair and third pair of coupled wheels reducing the
-rigid wheel-base for curves to 9 feet 8 inches. The four-wheel bogie
-truck in front carries only a moderate weight, being so close to the
-coupled wheels. Engines of this description require a strong permanent
-way, as there is a total weight of 60 tons on the four pairs of
-coupled wheels standing on a wheel-base of 15 feet 6 inches.
-
-Figs. 478 and 479 are types of tank-engines in use on some of the
-narrow-gauge (3 feet) railways. In general design they are somewhat
-similar to the modern class of engine on main lines of 4 feet 8½
-inches gauge, with four-wheel bogie truck in front, and four wheels or
-six wheels coupled, but with all the parts and weights smaller, to
-suit the narrow gauge and lighter permanent way.
-
-The extended use of the bogie truck is an admission of its advantage
-over the fixed-wheel arrangement, both for distribution of weight and
-facility in passing round curves; but although it is now so largely
-adopted for engines and carriages on our home and continental
-railways, it is somewhat of an anomaly to find it so very rarely used
-for tenders. In the United States all the locomotive tenders--and many
-of them of very large size and weight--are carried on two four-wheel
-bogie trucks, and traverse the curves as easily as the engines. On
-this side of the Atlantic, the prevailing custom is to mount the
-tender on six rigid wheels; and as many of these tenders weigh as much
-as from 35 to 40 tons in working order, and have a rigid wheel-base of
-15 feet, it will be seen at a glance that much unnecessary friction
-and wear and tear would be avoided by substituting two four-wheel
-bogie trucks for the fixed wheels.
-
-
-
-
-  CHAPTER VII.                                                            313
-
-  Signals--Interlocking--Block Telegraph and Electric Train
-  Staff Instruments.
-
-
-Signals.--Railway tradition alleges that on one of the early lines
-opened for passenger traffic, the precautions for public safety were
-considered to have been fulfilled by providing a man on horseback to
-ride along the track between the rails in the front of the locomotive
-engine, to give warning to persons strolling on the line, and to check
-the advance of the train when necessary. A very short experience of
-this method of working proved that the full capabilities of the
-locomotive could not be obtained from a restricted speed of seven or
-eight miles an hour, and a more comprehensive system of signalling had
-to be devised. By fencing in on both sides of the line, the public
-were prevented from making a general highway or promenade along the
-railway, and the problem was reduced therefore to the signalling for
-the trains alone.
-
-Flags of different colours, held by flagmen stationed at suitable
-places, answered the purpose for a while, or so long as the authorized
-running speed did not prevent the train being brought to a stand after
-sighting a flag warning the engine-driver to stop. As speeds were
-increased, a longer or more distant view of signals became imperative,
-and tall posts, or semaphore signals, were introduced. Well-defined
-blades or discs placed on high posts were easily worked from the
-ground-level, and could be seen for long distances, thus enabling the
-trains to be controlled or brought to a stand before reaching the
-signal. The efficiency of the principle once recognized, improvements
-and additions were made from time to time, until we have the simple
-acting tall semaphore signal so universally in use at the present
-time. The position of the signal arms or blades in the daylight, and
-the colours shown by the lamps at night, form the code of signals for
-the proper working of the train service; and as the signal arms and
-lamps are both worked simultaneously by the same gearing, it is only      314
-necessary to light the lamps to put the signals in complete condition
-for night-working. For some years, when the traffic was small, with
-trains at low speeds and at considerable intervals, one double-arm
-semaphore signal-post at a station was made to serve for all purposes;
-but as the train service became more frequent and more rapid, it was
-found that another semaphore or tall post signal, was necessary to
-give warning to the engine-driver some distance back before reaching
-the station or _home signal_. More particularly was this necessary at
-those stations where it was not intended that every train should stop.
-This new signal, called the _distant signal_, very soon came into
-general use. It was placed at distances varying from 400 to 800 yards
-away back from the station or home signal, and was worked by a long
-strained wire extending from the distant signal to a ground-lever
-placed near the home signal, the levers for these distant signals and
-home signals being thus near together and under the control of one
-man. More recently it was found necessary to introduce another
-important wire-worked signal called a _starting signal_, which is
-placed at the outgoing or departure end of the passenger platforms,
-lines, or station sidings, to prevent any train or engine starting or
-proceeding on its journey until such starting signal is lowered to
-indicate that the line is clear.
-
-These simple, independent, hand-worked semaphore signals did good
-service for many years, but being independent and in no way physically
-connected with one another at junctions, or stations, or with the
-switches they were intended to control, it was quite possible for
-mistakes to arise where everything depended upon the accuracy and
-prompt decision of the signalman. The possibility that such mistakes
-could occur, and the certainty that they actually did occur, and too
-often with most disastrous results, led gradually to the grouping and
-interlocking of a large number of signal levers and switch levers
-together in one signal cabin. The advantages of the concentrating and
-interlocking of signals and switches are twofold. In the first place,
-one man in the signal cabin can work and control the levers for a
-large number of switches and signals, where formerly several men were
-required to be located at various places in the station-yard; but the
-second, and by far the most important advantage, is that with proper
-interlocking arrangements it is practically impossible to give
-conflicting signals.
-
-With a modern interlocking frame, and assuming the normal position of     315
-all the signals to be at _danger_, then before a signal can be
-lowered for an approaching engine or train all the switches and
-corresponding signals, from any lines or sidings connecting with the
-line to be signalled _clear_ must first be set so as to prevent
-any engine or train coming out of such connecting lines or switches on
-to the line to be made clear. In a similar manner, before the points
-and signals can be set to permit an engine or train to pass from a
-siding on to the main line all the necessary signals must first be set
-to _danger_ to prevent the approach in either direction of any
-engine or train on the main line about to be occupied. The mechanical
-arrangements of the interlocking frame are so exact and complete as to
-effectually prevent any but the proper combination being made. An
-untrained or inexperienced signalman might inadvertently attempt to
-pull over a wrong lever, only to find it securely locked and immovable
-under the control of other levers. The proper sequence of levers must
-be made, and the accurately adjusted mechanism automatically prevents
-mistakes which formerly occurred with the old hand-worked signals from
-the oversight or confusion of the signalman.
-
-The interlocked switches or points are worked from the signal-cabin by
-light wrought-iron tubing (termed rodding) or channel-shaped iron bars
-supported on fixed iron rollers, and the signals by galvanized wires
-running over light pulleys. Modern signals are always weighted at the
-signal-post, so that in the event of the breaking of the pulling-wire
-they will fly back to their normal position of danger.
-
-The facility and precision secured by the interlocking machinery
-enabled other valuable accessories to be introduced for the more
-complete signalling and protection of train-working. Amongst these may
-be mentioned the facing-point bolt-lock and rocking-bar,
-signal-detectors at points, and throw-off or trap points.
-
-With the old-fashioned hand-worked switches the man standing alongside
-could see whether the sliding-rails were properly closed, and also
-when the last vehicle of the train had passed over them; but when
-important main-line-facing switches or points are worked by rodding
-from a signal-cabin some distance away, it is necessary to have some
-reliable means to ensure that the sliding-rails are actually brought
-close home, and also to prevent the switches being moved again until      316
-the entire train has passed over them. A set of switches may be
-carefully made and work well, but it is quite possible for some
-fracture or obstruction, to intervene and prevent them closing
-properly. If a train or engine were passing through them in a trailing
-direction, as indicated in Fig. 345, the wheels would most probably
-force the sliding-rail home, and no disturbance would arise. If,
-however, the train were coming in the opposite or facing direction,
-the chances are that some of the wheels would take one road and some
-the other, and cause a derailment. The same casualty would occur if
-the switches were moved during the passage of the train.
-
-To guard against the above contingencies, the facing-point bolt-lock
-and rocking-bar have been introduced. The system is applied in various
-forms, but the arrangement shown in Fig. 480 will explain the
-principle generally.
-
-A strong casting, A, is securely bolted to the top of the sleeper
-carrying the chairs on which rest the point ends of the sliding-rails.
-This casting has an internal groove or chamber formed for its entire
-length from C to D, as indicated by the dotted lines, and in which
-slides the locking-bolt B. The point ends of the switch or
-sliding-rails are connected by the transverse rod E, which is forged
-into a vertical bar form for that portion of its length, which passes
-through the opening, F, prepared for it in the casting A. In this
-vertical bar a hole or slot is cut to correspond to the exact size of
-the locking-bolt B, and at a distance to suit the sliding-rails when
-pulled over to their properly closed position. This locking-bolt, B,
-will not pass through the hole in the vertical bar until the
-sliding-rails are quite close home, and when once through the hole the
-sliding-rails cannot be moved until the locking-bar is withdrawn. In
-some cases two holes or slots are cut in the vertical bar to enable
-the points to be bolt-locked for both directions.
-
-The rocking-bar is designed to prevent the withdrawal of the
-locking-bolt before all the vehicles have passed over the points.
-
-[Illustration: Fig. 480, 483, 481, 482]
-
-This rocking-bar consists of an angle iron or tee-iron bar of a length
-equal to the longest wheel-base of the rolling-stock, and is carried
-on short pivoted arms working in cast-iron or wrought-iron brackets
-secured to the rails as shown in Fig. 481. The pivoted arms have a
-movement backward or forward, and when at either the one or the other
-extremity, the upper surface of the rocking-bar is sufficiently below     318
-the top of the rail to be well clear of the flange of any passing
-wheel; but while changing from the one to the other position, and when
-the pivoted arms are vertical, or at half-stroke, the upper surface of
-the rocking-bar is about level with the top of the rail, and right in
-the pathway of the wheel-flange. It is evident, therefore, that when
-the pivoted arms are set in the forward or backward position, and one
-of the wheels of a train or vehicle has passed on to the rail over the
-rocking-bar, the latter cannot be changed or raised and pulled over to
-the opposite extremity so long as any one of the wheels of the train
-or vehicles remain over the rocking-bar.
-
-As the same ground-crank which pulls over the pivoted arms from
-backward to forward also withdraws the locking-bolt B, the latter is
-thus held securely in the hole or slot of the transverse rod, E,
-until all the wheels of the train have passed off the rocking-bar. The
-operation of changing the points from one road to another is very
-simple. By means of the rodding G, worked by a lever in the
-signal-cabin, the locking-bolt B is first withdrawn from the slot;
-the points are then pulled over into the reverse position by the
-rodding H, and the locking-bolt B is again set back into one of
-the slots by the rodding G. Sometimes, for economy, the points,
-bolt-lock, and rocking-bar, are all three worked by one lever in the
-signal-cabin, and one set of rodding on the ground, as shown in Fig.
-482; but the arrangement is neither so perfect nor so secure as that
-shown in Fig. 480. Where there are two sets of rodding and gearing,
-the failure or breaking of either of them prevents the complete
-combination being made, and indicates at once to the signalman that
-something is wrong; but when there is only one set of rodding a
-breakage may occur without giving any tangible evidence to the
-signalman of the defect, and he may proceed to pull over his signal
-lever in ignorance that the points have not been properly made and
-bolted. To avoid an accident taking place from the failure of either
-rodding or gearing, the signal-detector has been devised, so as to
-prevent the possibility of pulling over the signal wire until the
-points and locking-bar are both in their proper positions.
-
-The signal-detector is applied in several forms; the one shown in
-Figs. 480 and 483 will explain the principle on which its efficacy
-depends. A transverse rod, I, attached to the sliding-rail, extends       319
-out beyond the rails, and is formed into a flat bar or plate, J,
-sliding through the guide-holes K, K in the casting L. Short
-upright levers, M and N, work on trunnions fixed in the casting,
-and to M and N are attached the wires leading from the
-signal-cabin and continuing on to the signal-posts, as shown in
-elevation in Fig. 483. Two slots are cut in the plate J to receive
-the curved arms of the levers M and N when they are drawn
-downwards to pull off the corresponding signals. Neither of the
-levers, M or N, can be drawn over unless there is a slot
-immediately under the curved arm into which it can enter. When there
-is solid plate under a curved arm, the short lever cannot be pulled
-over, and the signal therefore remains at danger. The slots in the
-plate J are spaced so that one will be brought into position for one
-of the curved arms, when the points are close home for the main line,
-and the other slot for the other curved arm, when the points are set
-for the branch line or siding. The two slots cannot be under the two
-curved arms at one and the same time, as one of the signals
-corresponds to the main line and the other to the branch line or
-siding.
-
-In some forms of signal-detector the transverse rod I is joined on
-to a vertical bar which slides through guide-holes in a casting
-something similar to the arrangement shown in the casting L.
-Longitudinal guide-holes, parallel to the line of rails, are made in
-the casting a little above the transverse rod-bar, and through the
-longitudinal guide-holes slide two vertical bars which are attached
-to, and form part of, the wire connections to the two signals. The
-wire bars have each a small tongue or rectangular fin forged on to the
-under side of the bar, and there is one corresponding channel cut in
-the transverse rod-bar. When the switches are properly closed in one
-position, the channel cut of transverse bar will be opposite one of
-the wire bar fins, and will allow one of the signals to be pulled over,
-but the other wire bar cannot be moved. The closing of the switches in
-the reverse position moves the channel cut so as to allow the other
-wire bar to be pulled through, but as there is only one channel cut in
-the transverse bar, only one signal can be pulled over for each
-position of the switches.
-
-[Illustration: Fig. 484, 485, 486, 490, 491, 487, 492, 488, 493, 496,
-489, 494, 495, 497]
-
-Throw-off or _trap points_, are introduced to throw an engine or train
-off the rails of a siding on to the ballast, and so avoid a collision
-with any other train which may be standing or passing on the line of
-rails with which such siding forms a connection. Fig. 484 is a diagram    321
-sketch of the arrangement, in which the main-line points are indicated
-by the letter A, and the trap points by the letter B; one series of
-rodding actuated by one lever in the signal-cabin works both the
-main-line points and the trap points at the same time and by the same
-movement. The connections are so made that when the points A are set
-for the passage of trains on the main line, the trap points B are set
-open to throw off on to the ballast, as shown in Fig. 484; and when
-the main-line points A are set to allow a train to pass from the
-siding on to the main line, the trap points B are closed, as shown on
-Fig. 485. A disc or other signal, worked or interlocked with the
-points, is placed near B to notify the engine-driver when he may pass
-out of the siding on to the main line; but should he from any cause
-proceed before the points are properly set and the corresponding
-signal given, his engine would run off at the ends of the rails C, C,
-and be derailed on to the ballast. The inconvenience caused by such
-derailment would be trifling compared with what might result from a
-collision with a train standing or passing on the main line. In some
-cases the siding is continued onwards for a considerable distance from
-the trap-point rails C, C, as indicated by the dotted lines D D, and
-terminates with a dead end. When this arrangement can be adopted,
-derailment is obviated, and the engine is brought to a stand by a
-buffer-stop at the end of siding. On no account should trap points be
-placed close to the top edge of a high embankment, or up to the
-abutment or wing walls of an under-line bridge, where an engine
-running through them accidentally might fall down a considerable
-height, and cause serious results. All sidings joining on to main
-lines should be trapped as above described, and when properly
-signalled and interlocked in the signal-cabin, the traffic-working can
-be carried on with increased facility and security.
-
-Fig. 486 is a sketch of an average sample of an ordinary single-arm
-wooden signal-post, with signal-arm, lamp, spectacles, ladder, and
-gearing complete for wire connection to signal-cabin. When the arm
-stands out in the horizontal position, representing the _danger_ or
-stop signal, the red spectacles will be in front of the lamps, and
-will show a red light to an approaching train. When the arm is
-lowered, as indicated by the dotted lines, the second spectacle will
-be in front of the lamps, and will show either a white or green light
-(according to the accepted code) as an _all-right_ signal for the         322
-train to proceed. For many years a white light was adopted for the
-all-right signal, but latterly, to prevent confusion with other white
-lights about a station, there has been an increasing disposition to
-use a green light as an all-right signal. Several railway companies
-have already effected the change, and others have arranged to follow
-their example. The counter-weight W keeps the signal-arm to the
-danger position, except when it is raised by the pulling over of the
-signal-wire from the signal-cabin working over the pulley P. Should
-the wire break when being pulled, the weight W falls down to the
-stop-plate, and the signal-arm rises to danger. The signal-posts may
-be of wood, wrought-iron, steel lattice-work, or cast-iron.
-
-The arms of _distant signals_ should be cut to a fish-tail shape, as
-in Fig. 487, to distinguish them from other signals. Goods-line
-signals should have a thin sheet-iron ring, as in Fig. 488. Sometimes
-purple glass is used instead of red glass for the spectacles of goods
-signals. Letters or numbers may be attached to signal-arms to signify
-the lines or sidings to which they correspond. Special signals are
-sometimes made with the arm working on a centre pin, as in Fig. 489.
-
-At junctions or places where two or three signals have to be fixed
-near together, it is customary to carry them on a bracket signal-post,
-as in Figs. 490 and 491. The former represents the home signals at an
-ordinary junction, the taller signal being for the main line and the
-lower one for the branch line. Fig. 491 shows the home signals at a
-junction where there is one line turning out of the main line to the
-left and another to the right. The taller signal in this case also
-serves for the main line and the two lower signals for the branch
-lines.
-
-In important station-yards, where there are a large number of lines
-and sidings running side by side, it is not always convenient or
-possible to place the respective signal-posts in suitable positions
-between the lines. To overcome the difficulty, the signals are erected
-on light overhead lattice girders, as shown in Fig. 492. In some
-cases, for want of a better position, or to obtain a more
-comprehensive view of the lines and signals, the signal-cabin is built
-on lattice girders, as in Fig. 493.
-
-Ground or _disc signals_ are fixed at the ground-level, and are worked
-in conjunction with trap points or outlet switches from sidings. In
-some cases they are worked direct by a connecting-rod from the            323
-switches, and serve merely as indicators to show whether the switches
-are lying for or against an engine passing out of the siding. In other
-cases they are worked independently from the signal-cabin by a
-separate lever and wire connection, the interlocking being so arranged
-that the lever working the switches must be pulled over before the
-lever working the disc signal can be moved. In one type the disc
-signal is fixed to a short vertical axis, as shown in Fig. 494, and by
-means of a cranked arm is made to rotate a quarter of a circle, so as
-to exhibit either a stop or advance signal according to the position
-in which the switches are lying. In another type, the lamp is fixed,
-and the red disc, with a red glass in the centre, is made to assume a
-horizontal or vertical position by a rod and crank, as shown in Fig.
-495.
-
-A simple arrangement of rodding and rollers for switch connections is
-shown in Fig. 496, the number of sets of rodding being determined by
-the number of connections to be made. Fig. 497 is a rodding
-compensator, to compensate or adjust for the difference in length of
-the rodding arising from variations in the temperature. The
-compensator may be used either vertically or horizontally, according
-to space or circumstances.
-
-Strong wrought-iron or steel cranks of different angles will be
-required when changing the direction of the rodding, or connecting to
-switches and facing point-locks. They must be firmly secured to strong
-timber framework well bedded in the ballast. For cranks working
-switches and bolt-locks, it is better to use extra long timbers under
-the rails instead of the ordinary sleepers. Cross-pieces can be bolted
-to the ends of the long timbers, and the cranks placed practically on
-the same timbers carrying the permanent way. By this means the rails
-and cranks can always be maintained in their proper relative positions
-as to distance, line, and level.
-
-Without a large series of diagrams it would be impossible to
-adequately describe the extent of signalling and interlocking required
-at large terminal stations and important roadside stations, but one or
-two simple examples may serve to illustrate the general principles.
-
-[Illustration: Fig. 498, 499]
-
-Fig. 498 represents the modern grouping of signals considered
-necessary at an ordinary double-line junction, showing all the signals
-at their normal or _danger_ position. The numbers marked on each
-indicate the numbers of the levers in the interlocking frame of the       325
-signal-cabin. Four distinct sets of trains have to be dealt with at
-this class of junction, and the interlocking must be so arranged that
-when the signals are lowered for the advance of any one train, no
-conflicting signals can be given to any other train.
-
-Assuming a train approaching from A, which has to continue on the main
-line past B on towards C, then the levers in the signal-cabin must
-first be pulled over to set the points 9 and bolt-lock 8 in proper
-position for the main line; and this operation will release the levers
-which have to be pulled over to lower the signals 5, 4, and 6, but at
-the same time will lock, and prevent the pulling over of the levers or
-lowering of the signals 2 and 1 for a train from A to B and D, or of
-the signals 14 and 15 for a train from D to B and A. The levers will,
-however, be free to pull over for setting the points 12 and lowering
-the signals 16, 17, and 13 for a train on the main line from C to B
-and A.
-
-In a similar manner, assuming a train approaching from D, which has to
-continue up to the main line at B and on towards A, then the lever in
-the cabin must first be pulled over to set the trailing points 12 in
-proper position; and this operation will release the levers which have
-to be pulled over to lower the signals 14 and 15, but at the same time
-will lock, and prevent the pulling over of the levers or lowering of
-the signals 5 and 4 for a train from A to B and C, or of the signals
-16 and 17 for a train from C to B and A. The levers will, however, be
-free to pull over for setting the points 9 and bolt-lock 8 and
-lowering the signals 2 and 1 for the passage of a train on to the
-branch line from A to B and D.
-
-For a train from C to B and A, the levers 12, 16, 17, and 13 would be
-required, and these would lock levers 14 and 15, and prevent the
-approach of any train from D to B, but they would leave free the
-levers necessary either for a train from A to B and C, or for a train
-from A to B and D, but only one of them at a time, the setting of the
-one series locking the other series.
-
-A train from A to B and D would require the proper setting of the
-points 9, bolt-lock 8, and signals 2, 1, and 3; and these would lock 5
-and 4, but would leave free the levers necessary either for a train
-from C to B and A, or for a train from D to B and A, but only one of
-them at a time.
-
-The cross-over road from the UP to DOWN main line, near the letter B      326
-on sketch, is only intended for use in case of break-down or
-accidents, and the normal position of the points is to lie clear for
-the passage of trains on the main lines. To use the cross-over road,
-the whole of the signals must first be set to _danger_ before the
-points 7 and 7 can be opened to permit the passage of an engine or
-train from the one main line to the other.
-
-The starting signals 6 and 3 should be placed sufficiently far away
-that the longest passenger or goods train may stand between them and
-the clearance points at G and E. These starting signals are of great
-service to train-working at junctions. Supposing a main-line train
-from A arriving at B before the section from B to C was clear, such
-train could be brought to a stand at signal 6, and remain there while
-another train from A was allowed to pass B, and proceed onwards
-towards D; or a branch-line train from A to D could be brought to a
-stand at 3, to allow a main-line train to proceed onwards from A to B
-and C. The starting signal 13 should be placed well in advance of the
-cross-over road to control anything passing from one line to the
-other.
-
-Fig. 499 shows the modern grouping of signals for an ordinary
-single-line junction. The arrangement is almost practically the same
-as for the double-line junction shown in Fig. 498, there being the
-same four distinct sets of trains to be controlled, but not any
-cross-over road. The signal-cabin is placed on the main line, a little
-in advance of the facing points, and a well-fenced-in gangway, the
-same height as the engine footplate, is carried out the proper
-distance from the rails, on which the signalman can stand to hand over
-or receive the train staff from the engine-driver when passing.
-
-At stations and places where there are several sidings and lines
-connecting with the main lines, at considerable distances apart, it
-will be necessary to have two or more signal-cabins placed in suitable
-positions, not only for expediting the working of the constant
-shunting movements, but also to insure that there is a signal-cabin
-within the regulation distance of all facing points on the main line.
-So far as the main line is concerned, the interlocking of these cabins
-must be connected, the one with the other, by slotting, or co-acting
-gearing, in such manner that the cabin in advance shall always be able
-to control the cabin in the rear in the lowering of the main-line
-signals for an approaching train. Fig. 376 is a diagram sketch of a       327
-typical double-line roadside station with two signal-cabins. The NORTH
-cabin has to work the signals and points in connection with the
-goods-shed, goods-sidings, and market branch, and the SOUTH cabin,
-those in connection with the coal and cattle sidings; and each of the
-cabins to work the signals and points of that portion of the main line
-adjoining its own cabin. For siding working, each cabin is quite
-distinct and independent of the other, but for main-line working the
-lowering of the signals can only be effected by the joint operation or
-co-acting of both cabins.
-
-Assuming a train approaching from A to proceed in the direction
-towards B, then, before the signalman in the NORTH cabin can lower the
-UP home-signal C, the signalman in the SOUTH cabin must first pull
-over his lever and release the slot which retains the signal C at
-_danger_, and in doing so the levers in his own cabin will stand
-locked, and prevent the lowering of the signal D, or opening of points
-E to allow access from the sidings to UP main line. The cross-over
-road F G will also be locked for main line clear. When the slot has
-been released from signal C, the signalman in NORTH cabin can lower
-the UP home signal C, but before he can pull over the lever for this
-purpose he must first lock the points H, to prevent access from the
-sidings to the UP main line, and also the points K L of the cross-over
-road, to keep the main line clear. A similar operation has to be gone
-through for a train approaching from B to proceed in the direction
-towards A, when the signalman in NORTH cabin must first withdraw the
-slot from the DOWN home-signal M before the signalman in the SOUTH
-cabin can lower that signal. A small automatic disc is placed in the
-cabin to indicate to the signalman when the slot has been withdrawn by
-his colleague in the neighbouring cabin, and for facility of working,
-the two cabins are usually placed in communication with each other by
-telegraph or telephone.
-
-At some stations similar to the above, where there is a very frequent
-train service, with several of the trains running through without
-stopping, it is the practice to have a second or lower arm to the home
-signals C and M, as shown on the diagram, these lower arms being only
-_pulled off_ for through or non-stopping trains, as an indication to
-the engine-driver that the line is clear in the section ahead.
-
-In addition to the leading signals shown in the sketches, there           328
-are shunting signals for the movement and marshalling of
-trains--setting-back signals in connection with the making up of
-passenger trains; taking on or off passenger carriages; or moving out
-empty passenger carriages; and many other special signals which become
-necessary for the working of a large and complicated train service.
-
-The above simple diagrams will explain some of the principal
-requirements to be kept in view when working out signalling
-arrangements. Where the lines and sidings are very numerous, as at
-important junctions and large terminal stations, the signalling
-becomes very intricate, and may require three or four cabins, slotted
-together in such manner that the necessary co-acting may be insured
-for the proper controlling of the mainline signals. Many of these
-signal-cabins contain a large number of levers, some of them having as
-many as a hundred, and a few of them two hundred and forty levers, or
-more, all of them so carefully arranged that no conflicting signal can
-be given. Not only has much skill to be exercised in the accurate
-adjustment of the interlocking machinery, but much study must be
-devoted to determine the exact duty of every lever, for the locking or
-releasing of other levers.
-
-Signal-cabins may be built of stone, brick, or wood. They should be
-roomy, well ventilated, and have abundance of light. Every
-signal-cabin should be placed in the position from which the signalman
-can obtain the best view of the signals and points under his charge.
-The height of the cabin floor will depend upon any obstacles that may
-intervene between the cabin and the signals, such as over-line
-bridges, station roofs, buildings, or other obstructions. Sometimes
-the floor has to be kept as low as five feet above rail-level, to
-secure a line of sight under the over-line bridges; and in others the
-floor has to be raised twenty, or even thirty feet above rail-level.
-
-[Illustration: Fig. 500, 508, 501, 502, 506, 507]
-
-Figs. 500, 501, and 502 show plan, transverse section, and elevation
-of a signal-cabin suitable for a small roadside station. The lower
-story and chimney-stack are of brick, and the upper story of wood,
-with slated roof. There is room for an interlocking frame of twenty or
-twenty-five levers, and space at the end of the cabin for the
-block-telegraph instruments, or electric train-staff instruments. The
-roof-work is open up to the slateboards, to obtain as much air
-capacity as possible. In the transverse section a winch for working
-mechanical gates is shown at the end of the interlocking frame. There     330
-is a liberal amount of glass, and two or three sliding windows, which
-the signalman can open to enable him to speak to the engine-drivers or
-others during shunting operations. The lower story of the cabin can be
-utilized for trimming lamps and keeping a small supply of coals and
-other stores. When working after dark the lamps in the cabins should
-be well protected by shades, to prevent the lights being seen by
-engine-drivers, and mistaken for signals.
-
-
-Interlocking.--There are several systems of interlocking, each of them
-varying considerably in the form and mode of application, but all of
-them having the same general object of securing or releasing the
-necessary levers for each combination of signalling movements. A brief
-description of one of the systems will explain the order in which the
-movements have to be made, and the security which can be obtained by
-the locking.
-
-Figs. 503, 504, and 505, are sketches illustrating one of the types of
-wedge and tappet interlocking. Each lever works on a fulcrum or pinion
-as at A, and has a lower arm B for lifting the rods leading off to
-points or signals, and an arm C to carry a counterweight when necessary.
-Cast-iron braces D are placed at convenient distances between the series
-of levers to carry the top frame E on which the lever floor casing
-F is bolted. This casing is continuous from end to end of the locking
-frame, with the exception of the narrow openings through which the
-levers travel when moving backwards or forwards. The sleeve-block
-G, resting in the depressed portions of the arc, retains the lever in
-position. When taking hold of the main lever L, the signalman’s hand
-draws the small side lever M, close to the main lever, and raises the
-sleeve-block G sufficiently high to pass over the top of arc F, the
-lever L can then be pulled or pushed over, and the block G will fall
-into the depression at the end of the stroke when the hand is removed.
-N is a tappet or thin flat bar attached to the main lever, and which
-works backwards or forwards between the wedges in the wedge frame O.
-The wedges move horizontally between guide pieces, and work either
-singly or are connected by the lower slide bars to other wedges some
-distance away on the frame according to the position of the levers
-which have to stand or move in unison for the releasing or locking. A
-strong cover is placed over the wedge frame to keep out the dirt.
-
-[Illustration: Fig. 503, 504, 505]
-
-Figs. 504 and 505 show plan views of four levers in a signal cabin        332
-taken just above the level of the tappets. In Fig. 504, all the levers
-are in their _normal_ or forward position, with the home and distant
-signals at _danger_, and the facing points leading into loop or siding
-lying for main line. Previous to the approach of a train on the main
-line, the home and distant signals have to be lowered, and will
-require the pulling over of levers 1 and 2; but these levers cannot of
-themselves be moved, as the wedges P and Q are locked by the straight side
-of lever 3. The operation would therefore be as follows:--points lever
-4 being set in its normal position for the main line would remain
-forward, lever 3 working the facing point bolt-lock would be pulled
-over, and in doing so would move the wedge R to the right into the
-recess of tappet of lever 4, locking that lever, and presenting the
-recess of its own tappet ready to receive the wedge Q. Lever 2 can
-then be pulled over, and will move the wedge Q to the right into the
-recess of tappet of lever 3, and present its own recess for wedge P.
-The pulling over of lever 1 completes the series, by moving the wedge
-P over to the right into the recess of tappet of lever 2. Fig. 505
-shows the positions of the tappets and wedges with the levers 1, 2,
-and 3, pulled over to make the combination described. Upon
-examination, it will be seen that levers 2, 3, and 4, are all securely
-locked, the points cannot be moved, nor the facing point bolt-lock
-withdrawn, nor the home signal changed until the lever 1 is pushed
-over again into its normal or _danger_ position. To restore the levers
-to their forward position, they must be set back in the reverse order
-to which they were pulled over. To simplify the explanation, only four
-levers are shown in the above sketches, but the principle is
-constantly extended out to a very large number of levers, and in many
-cases necessitates the introduction of several rows of wedges as
-indicated by the dotted lines. In some instances a combination is
-effected by pulling a certain lever only half over. In some systems
-the preliminary action or spring handle locking is adopted, in which
-the locking is actuated by the small side lever, similar to the one
-marked M on Fig. 503. The advocates of this arrangement claim
-increased security and precision in the interlocking, while on the
-other hand it is alleged that the mechanism is rendered more
-complicated without any corresponding advantage.
-
-
-Detached Lock.--Sometimes there is in the vicinity of a railway station,  333
-a siding which is too far away to be worked direct from a signal
-cabin, and not sufficiently used to warrant a separate cabin. Such
-sidings can be worked by a small ground frame opened or locked by a
-special key attached to the interlocking machinery in the adjoining
-signal cabin on a double-line railway, or attached to the train staff
-on a single line.
-
-Fig. 506 shows the arrangement applied to a double line with the
-outlying siding turning out of the UP main line, the points lying in a
-trailing direction for the running trains. Before the special and
-_only_ key can be withdrawn from its seat in the interlocking frame of
-the signal cabin, all the UP main line signals must be set to
-_danger_, and cannot be moved from _danger_ until the key is restored
-to its proper seat again. When the key is removed from the signal
-cabin, it can be taken to the ground frame at A, inserted in the key
-opening, and by turning it partly round, will release the bar which
-locks the levers of the facing point bolt-lock and the points. When
-these two levers are free the points can be opened, and vehicles moved
-into or out of the siding B C, but the special key cannot be withdrawn
-from the ground-frame A, until the points and facing point bolt-lock
-are put back again into their normal position for main line working.
-When the operations at the siding are completed, the special key can
-be removed, and taken back to its proper place in the signal-cabin,
-and ordinary working be resumed.
-
-Fig. 507 shows the application of the detached locks on a single line,
-and is a sketch of a portion of railway on which there is a small
-station B, with a goods siding F G, where the traffic is too small to
-require anything more than ground frames and detached locks. An
-engine-driver before leaving the station A, receives a train staff,
-which gives him possession of the line as far as C, including of
-course the intermediate station B, and this staff he must carry with
-him and hand over to the signalman on his arrival at the end of the
-section at C. At each of the points D and E is placed a two lever
-ground frame, similar to the one shown in Fig. 506, and attached to
-the train staff is a key, which will operate either of the two ground
-frames, but only one at a time, as the key must be inserted before the
-levers can be moved. When the train is proceeding in the direction
-from A to C, it will be more convenient to shunt vehicles into or out
-of the siding F G, by means of the points E, but when proceeding from
-C to A, the points D will be more convenient. Whichever of the points     334
-be used, they must be set, and bolt locked for the main line before
-the train staff and its key can be withdrawn from the ground frame and
-restored to the engine-driver. As the siding is _trapped_ at F and G,
-it is impossible for any vehicles to be moved out on to the main line
-except through the medium of the train staff and key. The same
-arrangement of detached lock is equally available for a single siding
-with only one set of points.
-
-
-Electric Repeater.--It will sometimes occur that on account of a curve
-or other obstacle, the arms and back lights of a distant or other
-signal cannot be seen from the signal cabin, and it is necessary to
-introduce an electric repeater. This little instrument consists of a
-miniature semaphore signal fixed in a metallic box with a glass front,
-and placed on a stand about a foot above the floor level immediately
-in front of the signal lever for which it is intended to serve as an
-indicator. Like the signal proper, the normal position of the
-miniature semaphore is at _danger_, but when the signal lever is
-pulled over in the cabin, the rod that pulls down the arm on the
-signal post effects a contact with an electric circuit which lowers
-the arm of the miniature semaphore at the same moment that the signal
-arm proper is lowered, and gives visible indication in the cabin that
-the signal is working. Fig. 508 is a sketch of one form of electric
-repeater.
-
-
-Detonators or fog signals are largely used in foggy weather and
-snowstorms, when the out-door signals cannot be seen from an
-approaching train. At such times the atmosphere is so dense, and the
-surrounding objects so obscured, that an engine-driver is totally
-unable to distinguish the usual landmarks which guide him on the
-approach to a station or semaphore, and he might easily pass by a
-signal unless he received an audible signal to indicate the position
-of the one that is invisible. Detonators are usually made in the form
-of a circular tin or metallic case about two inches in diameter, and
-three eighths of an inch thick, with soft metal clips on opposite
-sides for bending over and securing to the rails. The case is filled
-with detonating powder, which is crushed by the first wheel passing
-over it, and explodes with a loud report. It is customary to use these
-detonators in pairs placed a short distance apart in case one of them
-should fail to explode.
-
-Fog-signalling regulations vary on different railways, but the            335
-arrangements are generally carried out somewhat in the following
-manner. During the prevalence of a fog or snowstorm, a fog signalman
-is placed near each of the signal-posts to be protected, and is
-supplied with a hand signal-lamp, hand-flags, and a packet of
-detonators. So long as the arm of the signal-post at which he is
-alongside stands at _danger_, he must keep two detonators on the rail
-of that line which the signal controls, and also show a RED
-hand-signal (hand-flag by day, and hand-lamp after dark) to the
-approaching train. When the signal arm is lowered to show that the
-line is clear for the passage of the train, the fog signalman must
-remove the two detonators, and show a GREEN hand-signal (flag, or
-lamp) to the approaching train. When an engine driver hears the report
-of a detonator crushed by his engine, it is his duty to shut off steam
-immediately, and bring his engine to a stand, after which he must
-proceed very cautiously, until he receives further signals by hand or
-otherwise, or receives the line-clear signal to continue on his
-journey. Detonators are also of great service both in fine or bad
-weather, in cases of a wash away, a failure of works, or obstruction
-on the line, when a hand-signal may not be seen, but a detonator must
-be heard.
-
-
-Mechanical Gates.--Mechanical gates, worked and controlled from the
-inside of a signal-cabin, are now very largely adopted for public road
-level-crossings instead of ordinary hand-gates, opened and closed by a
-gateman walking from side to side of the line across the rails. Being
-worked from inside the cabin, they remove all possibility of the
-gateman being struck by a passing train; they move simultaneously, and
-can be opened or closed in very much less time than hand-worked gates,
-which have to be moved one by one, and being interlocked with the
-signals, the mechanical gates cannot be placed across the lines of
-rails until the train-signals in each direction are set at
-_danger_. When set for either train traffic or public road traffic,
-the gates are held firmly in position by metal stops, rising out of
-cast-iron boxes lying flush with the ground, and worked by a separate
-lever in the signal-cabin.
-
-Assuming the gates to be set for train traffic, and it is desired to
-open them for the public road traffic, the first operation will be to
-pull over the levers, and raise the signals in each direction to
-_danger_, and thus release the stop-lever, which can then be pulled
-over, to lower the gate-stops and allow the gate-winch to be turned,
-and the gates moved round into correct position. The stop-lever must      336
-then be set back to raise the stops and hold the gates secure. The
-train-signals will be retained at _danger_ by the interlocking
-gearing, and cannot be lowered until the gates are set back again
-across the public road, and the gate-stops raised.
-
-It is frequently urged that the celerity with which mechanical gates
-can be swung round and closed across the public road, is in itself a
-source of danger, and that persons preparing to cross the line might
-be struck by a moving gate, unless they received a distinct warning
-that such closing was about to take place. There is no doubt persons
-have been struck by such gates when closing across the road, and heavy
-claims for injuries have been decreed against railway companies, who
-were unable to prove that the man in charge had called out or given
-warning before moving the gates. To ensure that due and undeniable
-warning shall always be given, a firm of signal-makers have patented
-an appliance by which a powerful electric gong, fixed on the top of a
-tall post close to the gates, is sounded automatically by the gate
-machinery itself, and before the gates actually commence to move. As
-previously described, the pulling over of the lever to lower the
-gate-stops is the first operation to be performed whenever it is
-necessary to change the position of the gates, and it is the pulling
-over of this lever which actuates the apparatus, by bringing two
-electric points into contact, and thus starting the ringing of the
-gong or alarm. The gong continues to sound until the gates are moved
-over, the gate-stops raised, and the stop-lever put forward again into
-its normal position. The arrangement is very simple and very
-effective, and being purely automatic must work as regularly as the
-stop-lever. The tone and volume of the gong can be varied to suit
-circumstances. The public soon become familiar with its sound, and
-recognize its meaning.
-
-[Illustration: Fig. 509, 510]
-
-Figs. 509 and 510 give sketch plan and elevation of a set of
-mechanical gates for a public road level crossing on a double line of
-railway. The signal-cabin should be placed within a few yards of the
-gates, to enable the man in charge to have a good view of the persons
-and vehicles passing over the roadway. The underground gearing for
-working the gates and stops, must be protected by iron or wooden
-casing. The swinging portion of the wicket gates is closed, and held
-by a separate lever. The gates shown on the sketch are for a crossing
-on the square, but they can be equally well arranged for an oblique       338
-crossing, and of widths to suit the locality.
-
-
-Block-Telegraph Signalling.--However complete the outdoor signals and
-interlocking at any station, they can only control the movement of
-trains within their range, and something more is requisite to ensure
-the safe working of the traffic over the long lengths of line between
-stations. For some years a time-interval was allowed for the working
-of trains following one another on the UP and DOWN lines of a
-double line railway, no train being allowed to leave a station sooner
-than a fixed number of minutes after a previous train had started in
-the same direction. With this system there was always the risk that
-the first train might be overtaken and ran into by the second, and
-especially in the night time, or when the atmosphere was at all foggy.
-The electric telegraph was then called in to assist in the
-train-working, and brief telegrams were passed between the stations
-announcing the departure and arrival of trains. The increased security
-and convenience thus obtained led to the introduction of special
-electric telegraph instruments, devoted to the exclusive duty of
-train-working. These instruments, termed block telegraph instruments,
-are now almost universally used on all double lines of railway, and
-have largely contributed to the safe and efficient working of an ever
-increasing traffic. They are made in various forms, but the object of
-each is to ensure that before any train is allowed to start from, or
-pass any station, the signalman at that station shall receive from the
-signalman in the cabin in advance a distinct visible signal that the
-line is clear, and free of any train up to the cabin in advance; and
-also that after the train has been despatched, the signalman in the
-rear shall be at once advised when the train has arrived at the
-signal-cabin in advance. Fig. 511 is a sketch of one type of
-block-telegraph instrument, in which the leading feature is the
-miniature signal-post with its two arms, an arrangement which readily
-appeals to the eye of the signalman as being so similar in form and
-action to the fixed signals in the station. Each instrument is
-supplied with a bell or gong, by which the adjacent signalmen can
-communicate with each other, in accordance with a fixed code of
-signals which defines the relative numbers of strokes of the bell or
-gong, to represent certain regulation calls and answers. In the
-signal-cabins of the intermediate stations, two block-telegraph           339
-instruments are required, one for the section of the line to the left
-hand of the cabin, and the other for the section to the right. At the
-terminal stations only one instrument is required.
-
-In the instrument shown in Fig. 511, the upper arm of the miniature
-signal-post is coloured RED, and is moved by electricity through the
-medium of the block telegraph instrument in the signal-cabin in
-advance; and until this RED signal be lowered to the _line clear_
-position by the signalman in the cabin in advance, no train must be
-allowed to start from or pass the cabin in the rear. The lower
-signal-arm coloured WHITE is lowered by the plunger A on its own
-instrument by the signalman in charge, and at the same moment lowers
-by electricity the upper or RED arm of the block-telegraph instrument
-in the signal-cabin at the other end of the section. The lower or
-WHITE arm is thus restricted to the signals sent away from the
-signal-cabin, while the upper or RED arm is restricted to signals
-received in the signal-cabin. In the centre there is a round handle B,
-which rotates a circular disc inside the instrument, and on this disc
-are painted three distinct train inscriptions, only one of which can
-be seen at a time through the glazed opening. One inscription has the
-words ALL CLEAR painted in black letters on a WHITE ground; another
-has the words TRAIN ON LINE painted in white letters on a RED ground;
-and the third has the words TRAIN OFF, BUT SECTION BLOCKED painted in
-black letters on a GREEN ground. The instrument is considered to be in
-its _normal_ position when the GREEN inscription is in view, and both
-the miniature signal-arms raised to _danger_.
-
-Fig. 512 represents a portion of double line divided out into sections,
-or working blocks, between the stations B, C, and D. Each station is
-provided with the necessary block-telegraph instruments, and the usual
-distant, home, and starting semaphore signals.
-
-[Illustration: Fig. 511, 512, 513]
-
-Fig. 513 is a diagram sketch showing the pair of instruments as they
-stand on the instrument-tables in the signal-cabins B and C, where B^2
-and C^1 are the instruments which work together for the block section
-BC. Supposing a DOWN train proceeding from A in the direction of F,
-and approaching the signal-cabin of the block station at B, the DOWN
-starting signal standing at _danger_; then by the code of signals on
-the bell or gong the signalman at cabin B would communicate with the
-signalman at cabin C, to obtain _line clear_, so as to allow the          341
-approaching train to proceed on to C. If the previous train in the
-same direction had already passed C, and there was not any obstruction
-on the line, the signalman at C would give _line clear_ for the DOWN
-train, and to do so he would turn his circular disc to show the WHITE
-inscription ALL CLEAR, and then push in the plunger of his C^1
-instrument, lowering the DOWN or white arm, K, of his own instrument
-to the position shown by the dotted lines, which operation would at
-the same moment lower by electricity the DOWN or red arm, G, of the
-instrument B^2 in cabin B to the position of the dotted lines. The
-signalman at B would then lower his starting signal, to allow the DOWN
-train to proceed on towards C, and immediately the train had passed
-the starting signal he would, by means of his bell or gong advise the
-signalman at C that the train had entered the section, or block BC,
-and the signalman at C would at once turn his circular disc to show
-the RED inscription TRAIN ON LINE, and use his plunger to raise to
-_danger_ the DOWN or white arm, K, of his own instrument, and at the
-same time raise by electricity the DOWN or red arm, G, to danger in
-the instrument B^2 in cabin B. The section BC would then remain
-blocked until the DOWN train had arrived, or passed the station C,
-when the signalman there would, by means of his bell or gong advise
-the signalman at B that the DOWN train had passed out of the section,
-and would turn his circular disc to show the GREEN inscription TRAIN
-OFF, BUT SECTION BLOCKED. Both instruments would then be in their
-_normal_ positions, with the arms raised to danger, and ready for
-further train operations. In a similar manner for the UP-line trains
-on the section or block between C and B, the signalman in B cabin
-would turn his circular disc, and use his plunger to lower the UP or
-white arm, H, in his own instrument, B^2, and at the same moment lower
-by electricity the UP or red arm, I, of the instrument C^1 in cabin C,
-the other operation for train on line and train off being carried out
-for the UP train in the same routine as for the DOWN train. The
-outdoor fixed signals, or distant home and starting semaphore signals,
-have all to be worked to correspond to the block telegraph signals,
-and as the latter are always received well in advance of an
-approaching train, it follows that when the line is clear, the outdoor
-signals can be lowered so as to allow a through or non-stopping train
-to pass a block-telegraph station at full speed.
-
-Where the traffic is moderate, it may be sufficient to have               342
-block-telegraph instruments at each of the stations, but with a very
-frequent train service it will be found necessary to divide the line
-into shorter sections, and erect signal-cabins and block-telegraph
-instruments at intermediate points between stations.
-
-The code of bell or gong signals is extended to include various
-matters in connection with the train-working. For example, when a DOWN
-train is passing cabin B at full speed, the signalman may observe that
-there is something wrong--a carriage or waggon on fire, a tail-lamp
-missing, or other irregularity. It is too late to stop the train with
-his own signals, but by means of his bell or gong he can call upon the
-signalman in cabin C to stop and examine the train, and the DOWN
-distant and home signals at C can be raised to _danger_ before the
-train reaches the cabin at C.
-
-In every block-telegraph signal-cabin there is a train-book in which
-the signalman has to write down the time and description of every
-arriving or passing train, and, as this book lies before him, he has a
-complete record of the train-working, with the particulars of the
-exact times when the _line clear_ signals were given, and also when
-the train arrived or passed his signal-cabin.
-
-To guard against the possibility of a signalman inadvertently giving
-_line clear_, or allowing another train to pass his cabin before the
-previous train had reached the signal-cabin in advance, some railways
-have adopted the lock and block system. By this arrangement the
-starting signal at any cabin is electrically and mechanically locked
-from the cabin in advance, and can only be released or lowered by the
-action of the outgoing train itself when passing over a treadle or
-other appliance connected with the rails of the running-line at the
-signal-cabin in advance. This method practically gives the train the
-complete control of the section; and any signalman attempting, in
-error, to lower his starting signal would find it to remain fixed to
-_danger_ and immovable, until released by the arrival of the
-train at the advance cabin.
-
-
-Train-staff for Single Line.--When there is only a single line of
-railway for both an UP and DOWN train-service, very definite
-precautions must be adopted to prevent the meeting or collision of
-trains travelling in opposite directions. Where the piece of single       343
-line is short, and can be worked by one engine in steam, or two
-coupled together, no collision can take place, as the train-service
-will be limited to the one train moving backwards and forwards over
-the section; but with a long length of single line, including a large
-number of stations, necessitating several trains, some clear and
-comprehensive regulations must be introduced. For a long time the
-simple train-staff was found to give the desired security; there was
-only one staff for each pair of adjoining staff-stations, and no train
-was authorized to run without the staff, and as the staff could only
-be on one train at a time, the precaution against collisions was
-looked upon as complete. These staffs, which were generally made of
-brass, or other metal, were sufficiently large to be conspicuous when
-placed in the stand prepared for them on the engine. They were
-lettered to correspond to the stations to which they belonged, and
-were made in different patterns to distinguish them for their
-respective sections. No train was allowed to start from a station
-until the engine-driver received from the station-master the proper
-staff to authorize him to proceed to the next station, and on his
-arrival there it was the duty of the engine-driver to hand over the
-train-staff to the stationmaster of that place, and wait for another
-train-staff to authorize him to proceed over the next section. So long
-as the train service could be evenly arranged, and that there was
-always an UP train to take back a train-staff which has been carried
-out by a DOWN train, the simple staff worked most efficiently; but as
-the traffic increased, and two or more trains had to be despatched in
-the DOWN direction before one had to run in the UP direction, some
-auxiliary arrangement had to be introduced. This was effected by
-issuing train tickets, kept in a locked-up box, which could only be
-opened by the key attached to the train-staff. A properly dated
-train-ticket was handed to the engine-driver of the first DOWN train,
-and, if necessary, a second train-ticket to the engine-driver of a
-second DOWN train, and then the train-staff itself was handed to the
-engine-driver of the third DOWN train. There were one or two serious
-drawbacks to this train-staff and ticket-working. As there was only a
-time interval between the starting of the trains, the one train might
-overtake and run into the other with disastrous results. Again, a
-second or third train, which was put down in the schedule, might be
-withdrawn at the last moment, and the staff left behind at a station
-when it was required at the opposite end of the section, thus causing     344
-much confusion and delay. The ordinary electric telegraph could have
-been utilized to assist in regulating these train movements, but it
-was felt that a mere telegraph message was not sufficient to ensure
-positive safety, and that something more tangible was required in the
-shape of a staff, or token, without which no train should be allowed
-to travel on a single line of railway. To meet this requirement, the
-electric train-tablet, and the electric train-staff instruments have
-been invented, each of them being so arranged that upon any one
-section, or pair of instruments, a tablet or train-staff may be taken
-out from the instrument at either end of the section, but when once
-taken out, no other tablet or train-staff can be withdrawn from either
-instrument until the first has been delivered and placed again in one
-or other of the two instruments.
-
-Figs. 514, 515, and 516 are sketches of an electric train-staff
-instrument which has been very largely adopted on single lines, both
-at home and abroad.
-
-In a similar manner to the block-telegraph instruments for double
-line, the electric train-staff instruments have each a bell or gong by
-which the adjacent signalmen can communicate their calls and answers
-in accordance with a regulation code. In the signal-cabins of the
-intermediate stations two instruments are required, one for the staffs
-belonging to the section to the left of the cabin, and the other for
-the staffs of the section to the right. At a terminal station only one
-instrument is required.
-
-[Illustration: Fig. 514, 516, 515, 517]
-
-The head of the instrument contains the electrical and mechanical
-locking apparatus which controls the withdrawal of a train-staff, or
-is acted upon by its insertion. The circular name-plates and pointers,
-together with the galvanometer in the centre, serve as indicators to
-guide the signalmen in carrying out the various operations. The staffs
-usually consist of thin steel tubes, solid at the ends, with metal
-rings fixed upon them, as shown in the sketch, the number and position
-of the rings varying according to the section or pair of staff
-stations to which they belong; this difference in the rings
-effectually preventing the possibility of one set of staffs being used
-or inserted in either of the instruments of the adjoining sections.
-The staffs rest normally in the long vertical slot A, with the rings
-fitting in vertical grooves, which prevent the removal of any staff
-except by passing it along the curved slot BC, and out by the opening     346
-D, of large diameter. The electrical and mechanical locking apparatus
-is placed at the curved slot, and until the locking-bolt, which stands
-across the passage of the curved slot, be lifted by the joint
-operations of the signalmen and their instruments at both ends of the
-section, no staff can be withdrawn. When the instruments are standing
-in their _normal_ position of “staffs in,” the signalmen can arrange
-between them to withdraw a staff--say either from the NORTH cabin
-instrument or from the SOUTH cabin instrument of the section, but only
-from one of them; and the act of taking out that staff automatically
-locks both instruments, and prevents the possibility of taking out any
-other staff from either instrument until the staff already removed is
-restored and inserted in one or other of the instruments. From the
-above description it will be seen that the electric train-staff
-instrument provides for the safe working of two or more trains
-proceeding, one at a time, in the same direction over a section of
-single line, each one being supplied with a train-staff, which must be
-handed over at the end of a section before another staff can be issued
-for a following train. Should the train-staffs accumulate in one
-instrument, in consequence of more trains running in one direction
-than another, a re-distribution of staffs is effected by the
-authorized persons according to fixed regulations.
-
-In the diagram sketch, Fig. 517, a piece of single line is shown
-divided into sections or blocks, with loops or passing-places at the
-stations. At the station E a train-staff taken out of the instrument F
-serves for the section up to the instrument L at the station H; and on
-the train-staff is a key which will open the detached locks on the
-points of the small intermediate station, G, as described in Fig. 507,
-in connection with the working of detached locks. At the station H the
-engine-driver receives another staff from the instrument M, which
-takes him to the instrument N at station K, and in like manner on this
-staff is a key which will open the detached lock on the colliery
-siding points at I. At stations H and K are shown loops, or short
-pieces of double line, with platform to enable an UP train to cross or
-pass a DOWN train. The distance apart of the electric train-staff
-stations will depend greatly upon the number of the trains, and for a
-frequent train-service it may be necessary to have the instruments at
-every station, whether large or small. The electric train-staff is of
-great advantage in the working of ballast or construction trains, as      347
-a staff may be taken out of the instrument F at station E, which will
-give possession of the section as far as station H, and when the
-ballasting operations--which may be very near to E--are completed, the
-train can return to E, and deliver the staff again to the instrument
-F, instead of having to run the entire distance to station H. Although
-carrying a train-staff, the engine-driver must approach stations
-cautiously, and obey the fixed signals in the usual manner.
-
-
-
-
-  CHAPTER VIII.                                                           348
-
-  Railways of different ranks--Progressive improvements--Growing
-  tendency for increased speeds, with corresponding increase in
-  weight of permanent way and rolling-stock--Electricity as a
-  motive-power.
-
-
-Looking at railways in their present stage of development, they appear
-to be divided into three ranks, each one distinct from the other as
-regards its importance, capability, and prospects.
-
-In the first rank are the great trunk lines, which, at home or abroad,
-pass through thickly populated districts, rich in manufactures,
-minerals, or shipping industries, with their enormous movement of
-materials and people, and consequently requiring the most ample works,
-equipment, and appliances for security.
-
-In the second rank may be classed those railways which run through
-ranges of country where the population is moderate, or where the
-manufacturing industries are few in number and of minor importance.
-Although of the utmost value to the community of the long series of
-small towns and agricultural districts through which they pass, and
-forming the only great commercial highway, or connecting link, with
-some distant seaport, or leading business centre, the traffic returns
-upon such lines are too small to permit of the introduction of the
-more complete appliances and luxuries to be met with on the richer
-railways. In newly opened-out countries, and in distant colonies, such
-lines have often to struggle on for years against financial returns so
-small as to barely enable them to maintain a condition of efficiency;
-but where there are natural advantages in soil and climate, combined
-with a judicious development of all the available resources, the
-result will be the raising of the standard of the railway itself, and
-the enrichment of the entire district through which it passes. When
-laying out lines of this description, it may be necessary to curtail
-as much as possible the expenditure on works and equipment, but there
-should be no hesitation in obtaining liberal quantities of land for
-future enlargement of stations, or for constructing additional            349
-stations on promising sites. The value of the land may be small in the
-outset, but will be enhanced enormously as the benefits of the
-undertaking become appreciated.
-
-In the third rank may be grouped those branch lines which, starting
-from a main passenger or goods line, are laid down to some outlying
-town, seaport, or mining centre, which, although small, is considered
-of sufficient importance to be brought into railway communication. In
-general, these lines are laid to the same gauge as the line with which
-they connect, and the transfer of merchandise waggons is readily
-effected at the point of junction. Others, from motives of economy,
-have been laid down to a narrow gauge, involving the transhipment of
-all goods and cattle at the station where the break of gauge takes
-place. Most of these branch lines are laid out through the open
-country, like an ordinary standard railway, but with a minimum of
-works and appliances. Others are laid down partly on level public
-roads, and partly through the fields, and are in consequence subject
-to a statutory low rate of speed when travelling over those portions
-on the public roads.
-
-In many cases the construction of second and third rank railways, both
-at home and abroad, has been largely assisted by state or provincial
-aid. Such assistance must always be valuable to poor or undeveloped
-districts, but judgment should be exercised so as not to encourage the
-introduction of any scheme which would interfere or become competitive
-with any existing undertaking constructed by public enterprise. So
-long as capitalists invest their money more from commercial motives
-than from feelings of philanthropy, it would, to say the least, be
-unjust and impolitic for any country to adopt a course of competition
-by national funds, and so check the flow of public money into public
-undertakings. Ordinary public commercial competition may be business,
-as each party can value and compare their own prospects; but the
-competition of a scheme enjoying national aid and free money grants is
-very apt to become one-sided.
-
-There is every indication that even what may be termed a fourth-rank
-type of railway is destined to play a very important part in the
-industrial enterprises of many countries, and that in the form of
-little lines, made to any convenient gauge, and laid either along
-public roads or open country, or both, the produce from isolated
-manufactories, forests, quarries, and large farms will be conveyed to     350
-the nearest railway stations with greater facility and at much less
-expense than by carting along the public highway. Such little lines
-are available in places where the most sanguine promoter would
-hesitate to suggest an ordinary railway, and may be found to supply
-what is felt to be the missing link in the economical transport of a
-long list of materials of everyday use. As they would be almost
-exclusively intended for merchandise purposes, the statutory
-requirements would be on the most moderate scale, and as they would be
-generally constructed at the cost of the parties who had to operate
-them, the outlay would be restricted to the actual works necessary for
-convenience and efficiency. Similar little lines have been in use for
-many years in the busy yards of large ironworks, shipbuilders, and
-many other localities, where weighty masses of materials have to be
-moved from place to place in the course of manufacture, and it would
-be merely carrying out the same idea to a more extended range. The
-principal inducement for their introduction is the great advantage,
-both in convenience and cost, that is obtained by hauling a ton of
-materials over a pair of rails as compared with carting the same
-weight along an ordinary road; and as the fact becomes more and more
-proved by experience, these little fourth-rank lines will become more
-general. Numbers of them are in use at the present time, and some of
-them, even of only 2-feet gauge, are doing good service, the little
-trucks conveying manufactured goods to the nearest railway station and
-returning loaded with coals and other materials. By making suitable
-arrangements for passing places and junctions, the system could be
-carried out to considerable distances in thinly populated districts,
-and be made available by means of local sidings, to several places
-along the route. With a narrow-gauge type there would, of course,
-always be the time and expense of transhipment to or from the ordinary
-railway trucks in the same way as with the road carts, but the time
-and expense may be lessened by so constructing the little narrow-gauge
-trucks that the bodies may be readily lifted off the frames and
-wheels, and be placed like packing-cases in the railway waggons.
-
-It is natural to look to the railways of the first rank for the latest
-advances in construction, appliances, and equipment, and it is
-generally there they are found. Great trunk lines, crowded with
-traffic of all kinds, have not only the opportunity and means, but all
-the strong inducements to try or adopt any arrangement which promises     351
-greater facilities for dealing with the ever-increasing demands made
-on their carrying powers.
-
-Passenger and goods traffic are so dissimilar in their requirements
-that when both of them are steadily increasing it becomes difficult,
-if not impossible, to work the two classes over an ordinary double
-line. In some cases much assistance has been obtained by shortening
-the lengths of the working sections and introducing intermediate
-electric telegraph block stations between the ordinary stations. Long
-refuge-sidings have also been introduced at many of the signal-cabins
-or stations, into which goods trains can be shunted out of the way to
-allow fast passenger trains to pass through without stopping. Up to a
-certain extent this arrangement works fairly well, but where there is
-a very frequent service of fast and slow passenger trains, combined
-with a heavy and constant service of goods and mineral trains, the two
-lines of way are practically incapable of accommodating such a number
-of mixed trains without causing serious detentions. The goods trains
-must shunt out of the way some time before a passenger train is due,
-and this frequent shunting into sidings results in hours of delay in
-the transit of the goods and cattle traffic; and when one of such
-trains is allowed to proceed again on its way up to another station,
-dove-tailed as it may be between two fast passenger trains, there is
-always the tendency to run at a much higher rate of speed than is
-prudent for the class of rolling-stock of which the goods train is
-composed. To overcome this difficulty some railways have introduced
-additional UP and DOWN lines on the busiest part of their system,
-making four lines of way in all, two of these being reserved for the
-fast passenger and through trains, and the other two for slow trains,
-goods, and mineral trains. This arrangement of the four lines has
-afforded great relief to the traffic of all kinds, and has enabled the
-service to be worked with much greater facility and punctuality. The
-goods trains being restricted to their own separate lines, can proceed
-regularly in their order, at their uniform working speed, without
-having to resort to the spasmodic fast running too often expected from
-them when passing over some parts of an ordinary double line.
-Doubtless this four-line system, or rather the principle of laying
-down two additional lines of way, will go on extending, and will be
-accelerated in its accomplishment by the growing demand for still
-higher speed of our fast passenger trains, and still longer distances
-to be traversed without stopping. High-speed long-distance through        352
-trains can only perform their journeys with punctuality, when the
-route is kept clear of all other trains or obstructions which might
-interfere with their free running. Any check or stoppage in their
-course would cause loss of time and prestige.
-
-It is to be regretted that in so many of the cases where two
-additional lines of way have been laid down, more space was not left
-between the sets of rails for the fast traffic and those for the slow.
-In many instances the dividing space is not more than 7 or 8 feet. It
-would have been better and safer if it could have been made 20 feet.
-An ordinary goods train is made up of several kinds of trucks, some
-empty, some loaded, many of them unequally loaded, all of them subject
-to heavy work and rough handling, and more likely to give trouble than
-the higher class vehicle, the passenger carriage. The breaking down or
-derailment of one or two goods trucks on a line of rails close
-alongside the fast passenger rails, would in all probability so foul
-and obstruct the passenger line as to cause a very serious accident to
-an express train which could not be stopped in time. The greater width
-would not only provide more clearance in case of breakdowns, but would
-afford increased safety to the platelayers and other workmen engaged
-on the line. The permanent-way men have to be very watchful to keep
-out of danger on an ordinary busy double line, but they must be very
-much more on the alert where there are four lines of way close
-together side by side.
-
-In the neighbourhood of large cities and important manufacturing
-centres, railways have created a distinct traffic for themselves by
-providing means for a large portion of the population to reside in
-convenient suburbs. Local trains running at suitable business hours
-have induced people of all classes to select homes a few miles away
-from town, and the gradual growth of this suburban traffic has
-produced its own advantages and requirements. At the large terminal
-stations platform after platform has been added to accommodate the
-increased number of trains which arrive in the busy parts of the
-morning or depart in the evening. Every facility has to be provided to
-permit of the expeditious ingress and egress of the large crowds
-forming the respective trains--ample platforms, over-line
-foot-bridges, subways, convenient booking-offices, waiting-rooms, and
-left-luggage rooms.
-
-The enormous train service on some of these first-rank lines demands      353
-the highest efficiency in the signalling and interlocking
-arrangements, and the use of any devices which will ensure increased
-facility and safety in the working of the traffic. With a crowd of
-trains passing a signal-cabin in both directions, and often over four
-lines of way, it is quite possible for a signalman to make a mistake
-which cannot be rectified in time to prevent an accident. To obtain
-increased security many railways have adopted the lock and block
-system previously described, or some adaptation of the same principle,
-and this method of working will go on extending as the traffic
-increases. These additional appliances entail additional care and
-inspection, for although automatical machinery may be exempt from the
-human frailty of preoccupation of mind or forgetfulness, it is
-somewhat delicate in its organization, and requires constant
-supervision to maintain its efficiency.
-
-On many of the large lines, much has been done to give improved
-carriage accommodation. Carriages have been made longer, easier on the
-road, loftier, better furnished, and better lighted; but there is
-still a very great deficiency in those conveniences so essentially
-necessary, especially on trains running long distances without
-stopping. Drawing-room cars and dining-room cars are no doubt
-attractive, and may contribute considerably to the popularity of
-certain routes; but it is questionable whether many of the lines at
-home and abroad which have adopted such luxuries, have not in doing so
-commenced at the wrong end, and whether it would not have been more to
-the public satisfaction to have begun by first providing those
-conveniences which are found in every carriage on every line in the
-United States. It is satisfactory to find that there is a steadily
-growing tendency to so construct passenger carriages that their
-occupants may, by passages or corridors, communicate with all parts of
-the same carriage or with the adjoining carriages; and there is every
-reason to assume that the carriage of the future, either by
-legislation or consent, will combine both the items of conveniences
-and intercommunication, and will confer not only greater comfort to
-the passengers, but also increased protection against those outrages
-which, unfortunately, too frequently occur under the system of
-isolated compartments.
-
-It will be instructive to watch the results of the passenger receipts     354
-on those lines where only first and third-class carriages are used.
-The elimination of the second class may at first sight appear an
-innovation; but if there is not any pecuniary loss sustained, there
-must be a gain in the reduction of unoccupied seats to be hauled. It
-is customary to provide in every train a liberal number of spare seats
-of each class to meet contingencies; and the omission of one class may
-mean the saving of two or three carriages--a very important item in
-locomotive power.
-
-On important through lines high-speed running has become a leading
-feature, and compels a very efficient standard of perfection in works
-and rolling-stock to effect its attainment. There is no indication of
-remaining contented with what has been already accomplished; on the
-contrary, the spirit of restlessness is always urging to do something
-more. The travelling public speak as calmly now of a speed of seventy
-miles an hour as they did of thirty-five a few years ago; they
-thoroughly recognize the value of railways, and they merely desire to
-travel still faster. The incentives of emulation and competition are
-ever present to encourage further and further reduction of the running
-time, and the railway that offers a special fast through service for
-some of its passenger and mail trains, reasonably expects its
-popularity and patronage to be in the ascendant. Much has been done in
-permanent way and equipment to make the present high speeds possible,
-but more will be required if the speeds are to go on increasing. The
-passenger carriages for such work must be very substantial, and
-naturally heavy. The locomotives to haul a long train must have
-increased power and weight, and will necessitate stronger rails to
-carry the greater rolling loads. With the present system of
-motive-power, the heaviest item is the locomotive, and its weight must
-always determine and regulate the character of the works and permanent
-way. Rails weighing 90 pounds per yard are becoming common, and there
-is clear indication that before very long sections weighing from 100
-to 120 pounds, or more, per yard will be brought into use on many
-lines. There will be no difficulty in making a permanent way strong
-enough for rolling loads very far in excess of anything in the present
-practice; but it will be costly, and the extra expense per mile,
-extended over a few hundred miles, will represent a sum so large as to
-raise the question in many cases whether the probable advantages and
-additional remuneration to be obtained will warrant the outlay.
-
-To some extent the increased speed may be attained by dividing the        355
-present long trains into two shorter trains, with a fair interval of
-time between them. There are many splendid locomotives now running,
-which on a fairly level line can reach a speed of considerably over
-seventy miles an hour with a short train, but would be quite incapable
-of doing so with a long train. At the same time it is possible that if
-passengers increase in the same proportion as the inducements
-provided, the short train might not be sufficient for the numbers
-presented, and there would be no other alternative but to resort to
-still greater rolling loads and stronger hauling power.
-
-Perhaps electricity, which has already achieved so many marvels, is
-destined to take a still more prominent part as a motive-power in the
-working of ordinary railways, and may help out of the difficulty by
-inaugurating still higher speeds without the necessity of incurring
-stronger works or heavier permanent way. In addition to its success in
-the telegraph, in the telephone, and in its brilliant light,
-electricity is every day coming more and more to the front as a
-motive-power. At present many tramways and short lines, some of them
-in tunnel, some above ground, and many of them with very steep
-gradients, are successfully worked by electricity; but these, being of
-modern construction, were specially designed and equipped for that
-method of working, and none of them as yet resort to high speeds. Such
-rapid strides have, however, been already made in the progress of this
-system of haulage, as to promise that both increased power and speed
-will be forthcoming when the demand for them is made manifest. Various
-modes of application are being tried: overhead wires, underground
-wires, conductors on the level with the rails, storage batteries or
-accumulators, and self-contained electric motors, each and all of them
-being carefully tested to ascertain the comparative cost and
-efficiency. Much will depend upon the localities and advantages to be
-obtained for the respective generating stations. In places where a
-large, constant, and unutilized water supply is available, a great
-saving may be effected in the most expensive item of electric working,
-but in the greater number of cases steam-power will have to be adopted
-for driving the generating machinery. The main question will be
-whether electricity in its most approved form of application can haul
-a ton of paying load for one mile at a less average cost, and at as
-great or greater speed than the ordinary locomotive. Until there is       356
-very clear evidence that electricity is cheaper, there will not be any
-great inducement for its general use as a motive-power on ordinary
-railways.
-
-Experiments have been made on some existing railways to ascertain how
-far this new motive-power can be made serviceable under special
-circumstances. In one case, a powerful electric motor-car has been
-introduced for working frequent and heavy trains through a long
-tunnel, where the atmosphere with ordinary steam locomotives became
-foul almost to suffocation, and the result has shown that the traffic
-can be hauled efficiently by electricity, and the air in the tunnel
-maintained pure and clear. In this instance, the question of cost was
-of secondary importance, the primary object being to avoid the
-asphyxiating gases emitted from the ordinary locomotives.
-
-In other cases, specially designed electric motor-cars have been
-constructed with a view to obtain a higher speed for passenger trains
-than is at present attained with the locomotives, and the trials made
-have proved that these cars could reach a high speed, but so far only
-with limited loads. Experiments are still going on with larger and
-improved machines, from which it is expected to obtain both high speed
-and much increased hauling power.
-
-It is more than probable that amongst the earliest practical
-applications of electric motive-power on existing railways will be its
-introduction as an auxiliary on the steep gradients of some of the
-mountain railways abroad. In many of these regions there are millions
-of gallons of water running to waste down the ravines, a portion of
-which could be utilized in working powerful generating plant, to drive
-strong electric motor-cars for assisting the ordinary locomotives up
-the steep inclines. In such localities, with free water-power, the
-cost of the electricity would be at a minimum, while the cost of the
-ordinary locomotive would be at a maximum.
-
-In whatever form the electric motor-car may be designed, we are
-brought face to face with the old axiom, that there must be a certain
-amount of weight to obtain a certain amount of adhesion; but there
-will be one important point in favour of the motor-car, that whereas
-in the ordinary locomotive the weight for traction can only be
-distributed over a few working wheels, the electric arrangement may
-distribute it over a much greater number, and so diminish the
-insistent weight of each wheel upon the rails. There would also be the    357
-saving of the dead weight of the tender, the fuel, water, and other
-minor accessories, as well as the advantage that the active power
-would be applied in a rotary form instead of reciprocating.
-
-There are important interests at stake in the perfecting of this new
-system of haulage, and day by day new developments are being made to
-add to its efficiency and reduce its cost. Existing railways will,
-however, naturally require some very convincing proof of the all-round
-superiority of electricity before adopting that power generally
-in place of their present locomotives. The latter, with their
-corresponding workshops and appliances, represent so large an amount
-of invested capital, as to demand most thorough trials and
-investigation of the new power before they are superseded;
-nevertheless, if further experience proves that electrical power is
-better and cheaper than the ordinary steam locomotives, then the
-change will undoubtedly be made.
-
-Under whatever system of haulage the acceleration of trains be
-obtained, the increased speed will call for increased precautions in
-the selection and proving of the materials to be used in such service.
-Rails must be made more uniform in quality, and must be free from the
-imputation of fracture under regular wear. Notwithstanding the great
-improvements made in the preparation of the steel, and in the rolling,
-there are still far too many steel rails which break under traffic to
-allow rail-makers to rest satisfied with their work. Something is
-still wanting in the manufacture to effectually remove this
-disposition to fracture. The safe rail, the rail of the future, must
-be one that may bend and may wear, but will never break under ordinary
-use in the road. Axles must be stronger and tougher, as they will have
-to bear greater torsional strains than are now imposed upon them; and
-the wheels, of whatever type they are made, must be incapable of
-collapsing or falling to pieces upon the sudden and severe application
-of the brake-blocks. A train, rushing along at a speed of 70 or 80
-miles an hour, may on an emergency have to be brought to a stand in
-the shortest distance possible, and the failure of either axles or
-wheels in the endeavour to avert one form of accident would inevitably
-initiate another.
-
-To permit of unchecked high-speed running, many sharp curves will have
-to be flattened, bridges will have to be built at busy level
-crossings; and points, crossings, and junctions on the main lines will    358
-have to be reduced to the smallest possible number.
-
-It would be difficult to form an opinion as to how far passenger
-traffic will go on expanding, but if it continues to increase at the
-same rate as at present, some railways may find it expedient, and even
-absolutely necessary, to construct new lines altogether separate and
-apart from the existing routes, and for the sole use of their fast
-through traffic. As roadside or intermediate traffic would not form
-any part of the scheme, such lines could be laid out so as to keep
-away from the populous districts, where property would be costly, and
-pass instead through those parts of the open country where the most
-direct course and easiest gradients could be obtained. Stations would
-only be required at the very large and important places, and at long
-distances from each other. Lines of this description, reserved for
-through traffic only, taken alone, might not pay, but taken in
-conjunction with the existing lines, of which they would form a part,
-they might prove to be the best solution of the problem of dealing
-with a crowded train service, the remunerative earnings of which,
-placed together, might yield a rich return over the entire system. A
-project for a separate through line might at first appear a little
-startling, but we have well-known precedents in the vast expenditure
-already incurred in the constructing of enormous viaducts and
-connecting lines to avoid long detours on certain through routes. The
-widening out of an ordinary double line into a four-line road was at
-first considered as a rather venturesome departure; and it must always
-be costly because, in addition to the earthworks and permanent way,
-there is the doubling of all the over and under bridges and waterways,
-besides the great and expensive alterations at stations. Practically
-it is almost like making a second railway, and yet the constant
-extension of the principle is an admission that the working results
-have proved satisfactory, in spite of the large outlay. A little later
-the question will force itself more prominently into notice, whether
-the four-line track or the separate fast through traffic lines, will
-best answer the purpose. The former possesses certain advantages, but
-the latter would give more freedom for high-speed running.
-
-Engineers have brought railways to their present stage of perfection,
-and the public will expect them to devise and carry out still further
-improvements as the march of development moves onward. It is a simple     359
-matter to arrange the traffic on a railway when all the works and
-appliances are appropriate for the service to be performed; but the
-advances which are made follow one another so rapidly as to
-necessitate constant study and organization to effect the structural
-alterations and additions requisite to maintain an up-to-date standard
-of efficiency. The traffic manager on a railway receives his
-instructions from the directors or controllers of the company as to
-the working out of the train service, rates, charges, and other items
-of his department, but the engineer has to stand alone, and his
-technical knowledge and professional skill must enable him not only to
-design and construct works suitable in character, extent, and strength
-to the duty for which they are intended, but also to decide when
-structures are no longer capable of properly sustaining the increasing
-loads brought upon them, and must be taken down and replaced with
-others of a stronger description. For this reason the engineer must
-carefully consider every circumstance and local feature which may
-influence the design to be prepared; he must thoroughly investigate
-the nature of the ground for foundations, as the description when
-ascertained will frequently determine the class of work to be erected,
-whether in viaducts, bridges, or buildings; and in his selection of
-materials and calculations for strength, he must allow ample margin to
-meet further increased weights, as well as for natural deterioration.
-
-He should, indeed, go a little further, and as his perceptive ability
-and training will always enable him the more readily to foreshadow the
-direction in which improvements or changes are tending, he should
-study out and be prepared with his schemes to meet the new departures
-as the requirements gradually arise.
-
-Strength and efficiency are the leading points which must be always
-kept in view, and the engineer must never forget that he is solely
-responsible for the safety of the line and works, and of the public
-passing over the same.
-
-
-
-
-  INDEX                                                                   361
-
-
-  A
-
-  Accommodation works, 12
-  Air-lock, 119
-  Air-pump, 120
-  Allowances for sinkage on embankments, 70
-  Alteration of gradients, 12
-  ---- of roads, 6, 10
-  American hand-brake, 46
-  Analysis of steel rails, 193
-  Approach roads to stations, 249
-  Arch culverts, 76
-  Automatical gate-alarm, 336
-
-
-  B
-
-  Ballast, 225
-  Bascule bridge, 85
-  Battering-rule, 72
-  Bearing-weights of various materials, 129
-  Beater, 239
-  Bench marks, 66
-  Bissell truck, 58
-  Block crossing, cast steel, 235
-  ---- telegraph signalling, 18, 338
-  Board of Trade requirements, 18
-  Bog-cutting, 65
-  Bogie carriage, 54
-  ---- engine, 56, 306
-  Booking-hall, 249, 260
-  Book of reference, 8
-  Borings for foundations, 129
-  ---- for tunnel work, 164
-  Borrowed earthwork, 61
-  Bottom-pitching, 225
-  Bracket signals, 20, 322
-  Brake-power on gradients, 45
-  Brakes for goods waggons, 46
-  Brick-well foundations, 123
-  Bridges, 79
-  ---- over public roads, 10
-  Broken stone ballast, 225
-  Buffer-stops, 282
-  Bull-head rail, 191
-
-
-  C
-
-  Cab-rank, 251
-  Caisson foundations, 121
-  Cant of rail, 230
-  Carriage accommodation, 353
-  ---- bogie, 54
-  ---- dock, 282
-  ---- traverser, 292
-  Cast-iron column piers, 97
-  ---- in bridges, 27
-  ---- saddles, 224
-  ---- sleepers, 214
-  ---- tram-plates, 184
-  ---- tube tunnels, 179
-  ---- water-tanks, 299
-  Catch-siding, 26
-  Centre line of railway, 32
-  Chairs, 206
-  Channelling ballast, 231
-  Check-rails on sharp curves, 29, 51
-  Cinder ballast, 227
-  Circular running-shed, 289
-  Clay puddle, 127
-  Clocks at stations, 26
-  Coal-drops, 282
-  Coffer-dams, 127
-  Comparison of bull-head and flange rails, 199
-  Compound rails, 190
-  Concrete foundations, 114
-  Continuous brakes, 30
-  Cost of permanent way, 241, 242                                         362
-  Covered-way tunnels, 178
-  Crab bolts, 223
-  Cranes, 280, 294
-  Creosoted sleepers, 211
-  Cross-over road, 233
-  Crossings made of rails, 237
-  Cross-sections, 33
-  Culverts and drains, 74
-  Curve alterations, 12
-  Curves, 49
-  Cutting rails on curves, 229
-  Cylinder foundations, 116
-
-
-  D
-
-  Datum line, 8
-  Deck or floor of girder bridges, 133
-  Deposited plans, 4, 6
-  Depths of cuttings, 10
-  Derrick crane, 299
-  Detached lock, 332
-  Detonator or fog signals, 334
-  Detours on mountain-sides, 3
-  Deviation, limits of, 6
-  ---- of centre line, 12
-  ---- of levels, 12
-  Diagram sketches of bridges, 149
-  Diamond crossing, 237
-  Disc or ground signals, 322
-  ---- wheels, 48
-  Distant signal, 18, 314, 322
-  Diversion of roads, etc., 6
-  Dobbin-cart, 67
-  Dock platforms, 251
-  Double-line junction, 231
-  ---- slip points, 233
-  Dry stone backing, 162
-
-
-  E
-
-  Earthworks, 60
-  Edge rails, 185
-  Electric motive-power, 355
-  ---- repeater, 22, 334
-  ---- train-staff instrument, 344
-  Embankment on bog, 71
-  Engine bogie, 53, 56, 304
-  ---- triangle, 290
-  Engine turntables, 27, 289
-  Enlargements on parliamentary plans, 16
-  Entrances to tunnels, 176
-  Estimate, 14
-  Expansion of rails, 228
-  Extract from Government Standing Orders and Regulations, 6
-
-
-  F
-
-  Facing-bolt lock, 315
-  ---- points, 20
-  ---- ---- distance, 20
-  ---- point locks, 22
-  Fang clips, 224
-  Fastenings, 218
-  Fences enclosing line, 14, 73
-  ---- on bridges, 10
-  ---- on road approaches, 10
-  Fish bolts, 203, 220
-  ---- plates, 188, 203
-  ---- plate liners, 206
-  Flag signals, 313
-  Flag-top culverts, 76
-  Flange rail, 191
-  Floor or deck of girder bridges, 133
-  Floors for goods-sheds, 280
-  Flying junction, 231
-  Fog or detonator signals, 334
-  Footbridges, 26, 147, 149
-  Footings of foundations, 111
-  Foundations, 111
-  Four-line system, 351
-
-
-  G
-
-  Gantry crane, 294
-  Gate-alarm, 336
-  Gates for level crossings, 74
-  Gauge of railways, 37, 38
-  Girder bridges, 110
-  Glazed roofs over platforms, 272
-  Goliath crane, 297
-  Goods-sheds, 273
-  Government grants to railways, 349
-  ---- Standing Orders, 4, 6
-  Gradient alterations, 12
-  Gradients, 42
-  ---- influencing loads, 43
-  ---- in tunnels, 166
-  Gravel ballast, 225
-  ---- foundations, 113
-  Guard-rails, 51
-  Guide-piles, 127
-
-
-  H                                                                       363
-
-  Half-round sleepers, 211
-  Hand-brakes on trucks, 46
-  Headings in tunnels, 169
-  Headway and span of public-road bridges, 10
-  Height of platforms, 24
-  Heights of embankments, 10
-  High-level viaduct, 81, 83
-  High-speed running, 354
-  Home signals, 18, 314
-  Houses of labouring classes, 10
-
-
-  I
-
-  Inclination of ramps, 26
-  Inside keys for chairs, 207
-  Inspection of new line, 18
-  ---- of tunnel work, 176
-  Interlocking of signals, 22, 314, 330
-  Iron-tube tunnels, 179
-  Island-platform station, 258
-
-
-  J
-
-  Jack-arches of brickwork, 145
-  ---- of concrete, 139
-  Jib crane, 296
-  Jim Crow, 239
-  Junction signals, 20, 323
-  ---- with existing line, 6
-
-
-  K
-
-  Keys for chairs, 207
-  Kinsua Viaduct, 97
-
-
-  L
-
-  Lavatories and conveniences, 260
-  Laying permanent way, 225
-  Level crossings, 10
-  Life of steel rails, 193
-  Lift-bridge, 87
-  Light railways standard gauge, 41
-  Limits of deviation, 6, 16
-  Loa Viaduct, 102
-  Loads of locomotive engines, 44
-  Location of railway, 1
-  Lock and block signals, 342, 353
-  Longitudinal sleepers, 210
-  Low viaduct arching, 129
-  Low-level viaduct, 81, 83
-
-
-  M
-
-  Made ground, 111
-  Marking steel rails, 195
-  Mechanical drills, 172
-  ---- gates, 335
-  Mile-posts, 30
-
-
-  N
-
-  Names of stations, 24
-  Narrow-gauge railways, 40
-  Natural features of country, 1
-  ---- ground, 111
-  Navigable rivers, 81
-
-
-  O
-
-  Occupation bridges, 110
-  Ordinary crossing, 235
-  Ordnance maps, 3
-  Outside guard-rails, 53
-  ---- keys for chairs, 207
-  Over-line arch bridges, 103
-
-
-  P
-
-  Parapets on viaducts, 28
-  Parliamentary estimate, 14
-  ---- plan and section, 6, 8
-  Pedestal water-tanks, 302
-  Piers of cast iron, 97
-  ---- of masonry, 95
-  ---- of timber, 102
-  ---- of wrought-iron and steel, 97
-  Pile foundations, 114
-  Plate-iron troughing, 143
-  Platform roofs, 264
-  Platforms (requirements of), 24
-  Plenum system of sinking, 119
-  Pneumatic process of sinking, 129
-  Points, or switches, 235
-  Portage viaduct, 102
-  Power to purchase land, 6
-  Preservation of timber, 211
-  Private-road bridges, 110
-  Provincial grants to railways, 349
-  Public-road bridges, 10, 103
-  ---- level crossing, 8
-
-
-  R                                                                       364
-
-  Radial axle-boxes, 58
-  Rails, 182
-  Railway bills, 16
-  ---- Clauses Act, 6
-  ---- fences, 14
-  ---- slope, 61, 66, 72
-  Railways of different ranks, 348
-  Ramps to platforms, 24
-  Recommendations as to working of railways, 30
-  Rectangular running-sheds, 289
-  Reduced speed on curves, 50
-  Refuge sidings, 31, 351
-  Relative costs of narrow-gauge and light railways, 41
-  Renewal of under-line bridges, 151
-  Repeater signal, 22, 334
-  Requirements of Board of Trade, 18
-  Retaining walls, 159
-  Reverse curves, 51
-  Roadside station, 253
-  Rock foundations, 113
-  Rocking-bar, 316
-  Roof-principals, 264
-  Roofs over roadside platforms, 272
-  Rope-haulage, 49
-  Route of railway, 1
-  Royal assent, 16
-  Runaway points, 233
-
-
-  S
-
-  Safety-points, 24, 319
-  Sandy foundations, 113
-  Scales for Parliamentary plans, 6, 16
-  Scissors cross-over, 233
-  Screw piles, 114
-  Semaphore signals, 313
-  Semi-circular running-sheds, 289
-  Separate lines for through traffic, 358
-  Service roads, 69
-  Shafts in tunnels, 167
-  Sheeting-piles, 127
-  Side-cutting, 61
-  Side recesses in tunnels, 176
-  Sidings, 24
-  Signal-cabins, 328
-  Signal-detector, 315, 318
-  Signals, 313
-  ---- at junctions, 20, 323
-  Signals (requirements of), 20
-  Six-wheeled carriage, 54
-  Sleepers, 209
-  Slip-points, 233
-  Slope of cutting, 61
-  ---- of embankment, 66
-  Slotted signals, 326
-  Snake-heads, 184
-  Soft deep bog, 70
-  Soiling earthwork, 66
-  Sorting-sidings, 285
-  Span and headway of P. R. bridges, 10
-  Spans of large railway bridges, 158
-  Spikes, 222
-  Spirals, 35
-  Spoil-bank, 60
-  Sprags, 46
-  Square crossing, 233
-  Standing orders, 4, 6
-  Starting-signal, 18, 314
-  Station buildings, 260
-  ---- roofs, 264
-  Stations, 248
-  ---- near viaducts, 24
-  ---- on gradients, 26
-  Steel and wrought-iron sleepers, 217
-  ---- rails, 190
-  Steps for side-lying ground, 70
-  ---- of staircases, 26
-  Stone sleepers, 210
-  Strain on steel, 27
-  ---- on wrought-iron, 27
-  Suburban traffic, 352
-  Subways, 26
-  Super-elevation of rail, 230
-  Supervision of tunnel-work, 176
-  Swing-bridges, 83, 87
-  Switches or points, 235
-  Syphon culverts, 79
-
-
-  T
-
-  Tamping-bar, 239
-  Terminal station, 253
-  Tests for steel rails, 194
-  Three-throw switches, 233
-  Thrust-girders for retaining walls, 161
-  Tie-bars, 224
-  Timber bridges, 95
-  Timbering of tunnels, 170
-  Timber-pile foundations, 114
-  Time for construction, 18
-  Tip head, 67                                                            365
-  Tip-waggon, 69
-  Tools for permanent way, 239
-  ---- for tunnel-work, 172
-  Trailing-points, 20
-  Train-staff on single line, 342
-  Train-tickets, 343
-  Tramplates of cast-iron, 184
-  Tramway rails, 199
-  Trap-points, 319
-  Travelling-crane, 296
-  Traversing bridge, 85
-  Trimming slopes, 72
-  Trough girders, 135
-  Tunnel faces, or entrance, 176
-  ---- headings, 169
-  ---- sections, 176
-  ---- shafts, 167
-  Tunnels, 6, 10, 162
-  ---- composed of cast-iron segments, 179
-  ---- drainage of, 166
-  ---- through cities, 178
-  ---- under rivers, 181
-  Turn-out, 233
-  Turntables, 287
-
-
-  U
-
-  Under-line arch bridges, 103, 129
-
-
-  V
-
-  Vacuum system of sinking, 119
-  Verandah on platform, 261
-  Viaduct parapets, 28
-  Viaducts of timber, 95
-  ---- over rivers, 83
-  Viaducts over valleys, 91
-  ---- to be shown on section, 10
-
-
-  W
-
-  Waggon turn-table, 292
-  Waiting-rooms, 251
-  Warehouse crane, 294
-  Water-column, 302
-  Water-jet piles, 116
-  Water-tables, 227
-  Water-tanks, 299
-  Wear of fish-plates, 205
-  Wear of steel rails, 193
-  Weeping-holes, 161, 174
-  Weights of locomotive engines, 304
-  Well foundations, 123
-  Wheel-base of engine bogie, 59
-  Wheel-guards on viaducts, 28
-  Widths of public-road bridges, 10
-  Winding engines, 185
-  Wind-pressure, 28
-  Wooden-centre wheels, 48
-  Wooden culverts, 76
-  ---- screws, 223
-  ---- tramway, 182
-  ---- water-tanks, 301
-  Working plans and sections, 32
-  Wrought-iron column piers, 97
-  ---- and steel sleepers, 217
-  ---- piles, 116
-  ---- rails, 186
-  ---- water-tanks, 301
-
-
-  Z
-
-  Zigzags, 35
-
-
-
-
-PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, LONDON AND BECCLES.
-
-
-
-
-ENGINEERING, STRENGTH OF MATERIALS, ETC.
-
-
-THE STRENGTH OF MATERIALS AND STRUCTURES: the Strength of Materials as
-depending on their Quality and as ascertained by Testing Apparatus. By
-Sir J. ANDERSON, C.E., LL.D., F.R.S.E. With 66 Illustrations. Crown
-8vo, 3_s._ 6_d._
-
-
-RAILWAY APPLIANCES: a Description of Details of Railway Construction
-subsequent to the completion of the Earthworks and Structures. By Sir
-JOHN WOLFE BARRY, K.C.B., F.R.S. With 218 Illustrations. Crown 8vo,
-4_s._ 6_d._
-
-
-MECHANICS APPLIED TO ENGINEERING. By JOHN GOODMAN, Wh.Sch., M.I.C.E.,
-M.I.M.E., Professor of Engineering in the University of Leeds. With
-714 Illustrations and numerous Examples. Crown 8vo, 9_s._ net.
-
-
-RAILWAY APPLIANCES AND OPERATIONS. For the Use of Railway Employés. By
-EDWARD S. HADLEY, the Great Western Railway’s Divisional
-Superintendent’s Office, Newport, Monmouth. [_In the press._
-
-
-ENGINEER’S VALUING ASSISTANT: being a Practical Treatise on the
-Valuation of Colleries and Other Mines, etc. By H. D. HOSKOLD. With
-an Introductory Note by PETER GRAY. 8vo, 7_s._ 6_d._ net.
-
-
-PRACTICAL HYDRAULIC (WATER SUPPLY AND DRAINAGE) TABLES AND DIAGRAMS.
-By C. E. HOUSDEN. With 6 Plates and 7 Diagrams in the Text. Crown
-8vo, 3_s._ 6_d._
-
-
-PRACTICAL EARTHWORK TABLES. By C. E. HOUSDEN. With 9 Plates. Crown
-8vo, 2_s._ 6_d._
-
-
-A POCKET-BOOK FOR MECHANICAL ENGINEERS. By DAVID ALLAN LOW (Whitworth
-Scholar), M.I.Mech.E., Professor of Engineering, East London Technical
-College. With over 1,000 specially prepared Illustrations. Fcp. 8vo,
-gilt edges, rounded corners. 7_s._ 6_d._
-
-
-MECHANICS FOR ENGINEERS: a Text-book of Intermediate Standard. With
-200 Diagrams and numerous Examples. By ARTHUR MORLEY, M.Sc.,
-Professor of Mechanical Engineering in University College, Nottingham.
-Crown 8vo, 4_s._ net.
-
-
-STRENGTH OF MATERIALS. By ARTHUR MORLEY, M.Sc., Professor of
-Mechanical Engineering in University College, Nottingham. With 248
-Diagrams and numerous Examples. 8vo, 7_s._ 6_d._ net.
-
-
-LIGHT RAILWAY CONSTRUCTION. By RICHARD MARION PARKINSON, Assoc.
-M.Inst.C.E. With 85 Diagrams. 8vo, 10_s._ 6_d._ net.
-
-
-GRAPHICS; or, the Art of Calculation by Drawing Lines, applied
-especially to Mechanical Engineering. By ROBERT H. SMITH, formerly
-Professor of Engineering, Mason College, Birmingham. Part I. With
-separate Atlas of 29 Plates containing 97 Diagrams. 8vo, 15_s._
-<!--385.png-->
-
-
-THE THEORY OF STRESSES IN GIRDERS AND SIMILAR STRUCTURES; with
-Practical Observations on the Strength and other Properties of
-Materials. By BINDON B. STONEY, LL.D., F.R.S., M.I.C.E. With 5
-Plates and 143 Illustrations in the Text. Royal 8vo, 36_s._
-
-
-THE TESTING OF MATERIALS OF CONSTRUCTION. A Textbook for the
-Engineering Laboratory and a Collection of the Results of Experiment.
-By W. CAWTHORNE UNWIN, F.R.S., B.Sc. With 5 Plates and 188
-Illustrations and Diagrams. 8vo, 16_s._ net.
-
-
-ENGINEERING CONSTRUCTION IN IRON, STEEL, AND TIMBER. By WILLIAM
-HENRY WARREN. With 13 Folding Plates and 375 Diagrams. Medium
-8vo, 16_s._ net.
-
-
-THE SEA COAST: Destruction, Littoral Drift, Protection. By W. H.
-WHEELER, M.Inst. C.E. With 38 Illustrations and Diagram. Medium 8vo,
-10_s._ 6_d._ net.
-
-
-A PRACTICAL MANUAL OF TIDES AND WAVES. By W. H. WHEELER, M.Inst.
-C.E. With 19 Illustrations. 8vo, 7_s._ 6_d._ net.
-
-
-MACHINE DRAWING AND DESIGN.
-
-
-AN INTRODUCTION TO MACHINE DRAWING AND DESIGN. By DAVID ALLAN LOW,
-M.I.Mech.E. With 153 Illustrations and Diagrams. Crown 8vo, 2_s._
-6_d._
-
-
-A POCKET-BOOK FOR MECHANICAL ENGINEERS. By DAVID ALLAN LOW,
-M.I.Mech.E. Fcp. 8vo, 7_s._ 6_d._
-
-
-THE DIAGRAM MEASURER. An Instrument for Measuring the Areas of
-Irregular Figures, and specially useful for determining the Mean
-Effective Pressure from Indicator Diagrams from Steam, Gas and other
-Engines. By DAVID ALLAN LOW, M.I.Mech.E. With full instructions, 1_s._
-
-
-A MANUAL OF MACHINE DRAWING AND DESIGN. By DAVID ALLAN LOW and ALFRED
-WILLIAM BEVIS. With over 700 Illustrations. 8vo, 7_s._ 6_d._
-
-
-MACHINE DESIGN, CONSTRUCTION AND DRAWING: a Textbook for the Use of
-Young Engineers. By HENRY J. SPOONER, C.E., M.I.Mech.E., F.G.S., etc.,
-Director and Professor in the Polytechnic School of Engineering. With
-86 Tables and numerous Exercises. Illustrated by over 1,400 Drawings
-and Figures. 8vo, 10_s._ 6_d._ net.
-
-
-MACHINE DRAWING AND DESIGN FOR BEGINNERS: an Introductory Work for the
-Use of Technical Students. By HENRY J. SPOONER, C.E., M.I.Mech.E.,
-F.G.S., etc., Director and Professor in the Polytechnic School of
-Engineering. Crown 4to, price 3_s._ 6_d._
-
-
-THE ELEMENTS OF MACHINE DESIGN. PART I. General Principles; Strength
-of Materials; Rivets, Bolts, and other Fastenings; Journals and
-Shafting; Couplings; Pedestals; Transmission of Power by Gearing,
-Belting, Ropes, and Chains. By W. CAWTHORNE UNWIN, LL.D., F.R.S.,
-B.Sc., M.I.C.E., Hon. Mem. Inst. Mech. E., Hon. Mem. Am. Soc. Mech.
-E., Foreign Hon. Mem. Am. Academy of Arts and Sciences. With 387
-Figures. 8vo, 7_s._ 6_d._ net.
-
-PART II. Chiefly on Engine Details. With 259 Diagrams, etc. Crown 8vo,
-6_s._
-
-
-LONGMANS, GREEN, & CO.
-
-LONDON, NEW YORK, BOMBAY, AND CALCUTTA.
-
-
-
-
-Transcriber’s Note:
-
-Unprinted punctuation was added, where appropriate. The illustrations
-identified as numbered figures are all full-page without captions. When
-illustrations interrupt the text of a paragraph, they were moved to
-precede that paragraph. For ease of use of the index, page numbers are
-displayed in the right margin for only pages that contain text.
-
-Words and phrases in italics are surrounded by underscores, _like
-this_. Superscripted letters and numbers are preceded by a carat, e.g.
-C^o. Use of hyphens was made consistent. Obsolete and alternative
-spellings were left unchanged. Spelling corrections are noted below:
-
-  ‘transhipment’ to ‘transshipment’ ... delay in transshipment... pg 41
-  ‘steepier’ to ‘steeper’ ... introduce steeper gradients ... pg 45
-  ‘guage’ to ‘gauge’ ... 8½ inch gauge,... pg 48
-  ‘guage’ to ‘gauge’ ... on 3-foot narrow-gauge railways ... pg 193
-  ‘breaks’ to ‘brakes’ ... the working of the brakes.... pg 193
-  ‘petition’ to ‘partition’ ... plate partition across ... pg 301
-  ‘close’ to ‘closed’ ... is kept closed by the pressure ... pg 302
-
-
-
-
-
-End of Project Gutenberg's Railway Construction, by William Hemmingway Mills
-
-*** END OF THIS PROJECT GUTENBERG EBOOK RAILWAY CONSTRUCTION ***
-
-***** This file should be named 50696-0.txt or 50696-0.zip *****
-This and all associated files of various formats will be found in:
-        http://www.gutenberg.org/5/0/6/9/50696/
-
-Produced by Chris Curnow, Carol Brown, and the Online
-Distributed Proofreading Team at http://www.pgdp.net (This
-file was produced from images generously made available
-by The Internet Archive)
-
-
-Updated editions will replace the previous one--the old editions will
-be renamed.
-
-Creating the works from print editions not protected by U.S. copyright
-law means that no one owns a United States copyright in these works,
-so the Foundation (and you!) can copy and distribute it in the United
-States without permission and without paying copyright
-royalties. Special rules, set forth in the General Terms of Use part
-of this license, apply to copying and distributing Project
-Gutenberg-tm electronic works to protect the PROJECT GUTENBERG-tm
-concept and trademark. Project Gutenberg is a registered trademark,
-and may not be used if you charge for the eBooks, unless you receive
-specific permission. If you do not charge anything for copies of this
-eBook, complying with the rules is very easy. You may use this eBook
-for nearly any purpose such as creation of derivative works, reports,
-performances and research. They may be modified and printed and given
-away--you may do practically ANYTHING in the United States with eBooks
-not protected by U.S. copyright law. Redistribution is subject to the
-trademark license, especially commercial redistribution.
-
-START: FULL LICENSE
-
-THE FULL PROJECT GUTENBERG LICENSE
-PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
-
-To protect the Project Gutenberg-tm mission of promoting the free
-distribution of electronic works, by using or distributing this work
-(or any other work associated in any way with the phrase "Project
-Gutenberg"), you agree to comply with all the terms of the Full
-Project Gutenberg-tm License available with this file or online at
-www.gutenberg.org/license.
-
-Section 1. General Terms of Use and Redistributing Project
-Gutenberg-tm electronic works
-
-1.A. By reading or using any part of this Project Gutenberg-tm
-electronic work, you indicate that you have read, understand, agree to
-and accept all the terms of this license and intellectual property
-(trademark/copyright) agreement. If you do not agree to abide by all
-the terms of this agreement, you must cease using and return or
-destroy all copies of Project Gutenberg-tm electronic works in your
-possession. If you paid a fee for obtaining a copy of or access to a
-Project Gutenberg-tm electronic work and you do not agree to be bound
-by the terms of this agreement, you may obtain a refund from the
-person or entity to whom you paid the fee as set forth in paragraph
-1.E.8.
-
-1.B. "Project Gutenberg" is a registered trademark. It may only be
-used on or associated in any way with an electronic work by people who
-agree to be bound by the terms of this agreement. There are a few
-things that you can do with most Project Gutenberg-tm electronic works
-even without complying with the full terms of this agreement. See
-paragraph 1.C below. There are a lot of things you can do with Project
-Gutenberg-tm electronic works if you follow the terms of this
-agreement and help preserve free future access to Project Gutenberg-tm
-electronic works. See paragraph 1.E below.
-
-1.C. The Project Gutenberg Literary Archive Foundation ("the
-Foundation" or PGLAF), owns a compilation copyright in the collection
-of Project Gutenberg-tm electronic works. Nearly all the individual
-works in the collection are in the public domain in the United
-States. If an individual work is unprotected by copyright law in the
-United States and you are located in the United States, we do not
-claim a right to prevent you from copying, distributing, performing,
-displaying or creating derivative works based on the work as long as
-all references to Project Gutenberg are removed. Of course, we hope
-that you will support the Project Gutenberg-tm mission of promoting
-free access to electronic works by freely sharing Project Gutenberg-tm
-works in compliance with the terms of this agreement for keeping the
-Project Gutenberg-tm name associated with the work. You can easily
-comply with the terms of this agreement by keeping this work in the
-same format with its attached full Project Gutenberg-tm License when
-you share it without charge with others.
-
-1.D. The copyright laws of the place where you are located also govern
-what you can do with this work. Copyright laws in most countries are
-in a constant state of change. If you are outside the United States,
-check the laws of your country in addition to the terms of this
-agreement before downloading, copying, displaying, performing,
-distributing or creating derivative works based on this work or any
-other Project Gutenberg-tm work. The Foundation makes no
-representations concerning the copyright status of any work in any
-country outside the United States.
-
-1.E. Unless you have removed all references to Project Gutenberg:
-
-1.E.1. The following sentence, with active links to, or other
-immediate access to, the full Project Gutenberg-tm License must appear
-prominently whenever any copy of a Project Gutenberg-tm work (any work
-on which the phrase "Project Gutenberg" appears, or with which the
-phrase "Project Gutenberg" is associated) is accessed, displayed,
-performed, viewed, copied or distributed:
-
-  This eBook is for the use of anyone anywhere in the United States and
-  most other parts of the world at no cost and with almost no
-  restrictions whatsoever. You may copy it, give it away or re-use it
-  under the terms of the Project Gutenberg License included with this
-  eBook or online at www.gutenberg.org. If you are not located in the
-  United States, you'll have to check the laws of the country where you
-  are located before using this ebook.
-
-1.E.2. If an individual Project Gutenberg-tm electronic work is
-derived from texts not protected by U.S. copyright law (does not
-contain a notice indicating that it is posted with permission of the
-copyright holder), the work can be copied and distributed to anyone in
-the United States without paying any fees or charges. If you are
-redistributing or providing access to a work with the phrase "Project
-Gutenberg" associated with or appearing on the work, you must comply
-either with the requirements of paragraphs 1.E.1 through 1.E.7 or
-obtain permission for the use of the work and the Project Gutenberg-tm
-trademark as set forth in paragraphs 1.E.8 or 1.E.9.
-
-1.E.3. If an individual Project Gutenberg-tm electronic work is posted
-with the permission of the copyright holder, your use and distribution
-must comply with both paragraphs 1.E.1 through 1.E.7 and any
-additional terms imposed by the copyright holder. Additional terms
-will be linked to the Project Gutenberg-tm License for all works
-posted with the permission of the copyright holder found at the
-beginning of this work.
-
-1.E.4. Do not unlink or detach or remove the full Project Gutenberg-tm
-License terms from this work, or any files containing a part of this
-work or any other work associated with Project Gutenberg-tm.
-
-1.E.5. Do not copy, display, perform, distribute or redistribute this
-electronic work, or any part of this electronic work, without
-prominently displaying the sentence set forth in paragraph 1.E.1 with
-active links or immediate access to the full terms of the Project
-Gutenberg-tm License.
-
-1.E.6. You may convert to and distribute this work in any binary,
-compressed, marked up, nonproprietary or proprietary form, including
-any word processing or hypertext form. However, if you provide access
-to or distribute copies of a Project Gutenberg-tm work in a format
-other than "Plain Vanilla ASCII" or other format used in the official
-version posted on the official Project Gutenberg-tm web site
-(www.gutenberg.org), you must, at no additional cost, fee or expense
-to the user, provide a copy, a means of exporting a copy, or a means
-of obtaining a copy upon request, of the work in its original "Plain
-Vanilla ASCII" or other form. Any alternate format must include the
-full Project Gutenberg-tm License as specified in paragraph 1.E.1.
-
-1.E.7. Do not charge a fee for access to, viewing, displaying,
-performing, copying or distributing any Project Gutenberg-tm works
-unless you comply with paragraph 1.E.8 or 1.E.9.
-
-1.E.8. You may charge a reasonable fee for copies of or providing
-access to or distributing Project Gutenberg-tm electronic works
-provided that
-
-* You pay a royalty fee of 20% of the gross profits you derive from
-  the use of Project Gutenberg-tm works calculated using the method
-  you already use to calculate your applicable taxes. The fee is owed
-  to the owner of the Project Gutenberg-tm trademark, but he has
-  agreed to donate royalties under this paragraph to the Project
-  Gutenberg Literary Archive Foundation. Royalty payments must be paid
-  within 60 days following each date on which you prepare (or are
-  legally required to prepare) your periodic tax returns. Royalty
-  payments should be clearly marked as such and sent to the Project
-  Gutenberg Literary Archive Foundation at the address specified in
-  Section 4, "Information about donations to the Project Gutenberg
-  Literary Archive Foundation."
-
-* You provide a full refund of any money paid by a user who notifies
-  you in writing (or by e-mail) within 30 days of receipt that s/he
-  does not agree to the terms of the full Project Gutenberg-tm
-  License. You must require such a user to return or destroy all
-  copies of the works possessed in a physical medium and discontinue
-  all use of and all access to other copies of Project Gutenberg-tm
-  works.
-
-* You provide, in accordance with paragraph 1.F.3, a full refund of
-  any money paid for a work or a replacement copy, if a defect in the
-  electronic work is discovered and reported to you within 90 days of
-  receipt of the work.
-
-* You comply with all other terms of this agreement for free
-  distribution of Project Gutenberg-tm works.
-
-1.E.9. If you wish to charge a fee or distribute a Project
-Gutenberg-tm electronic work or group of works on different terms than
-are set forth in this agreement, you must obtain permission in writing
-from both the Project Gutenberg Literary Archive Foundation and The
-Project Gutenberg Trademark LLC, the owner of the Project Gutenberg-tm
-trademark. Contact the Foundation as set forth in Section 3 below.
-
-1.F.
-
-1.F.1. Project Gutenberg volunteers and employees expend considerable
-effort to identify, do copyright research on, transcribe and proofread
-works not protected by U.S. copyright law in creating the Project
-Gutenberg-tm collection. Despite these efforts, Project Gutenberg-tm
-electronic works, and the medium on which they may be stored, may
-contain "Defects," such as, but not limited to, incomplete, inaccurate
-or corrupt data, transcription errors, a copyright or other
-intellectual property infringement, a defective or damaged disk or
-other medium, a computer virus, or computer codes that damage or
-cannot be read by your equipment.
-
-1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right
-of Replacement or Refund" described in paragraph 1.F.3, the Project
-Gutenberg Literary Archive Foundation, the owner of the Project
-Gutenberg-tm trademark, and any other party distributing a Project
-Gutenberg-tm electronic work under this agreement, disclaim all
-liability to you for damages, costs and expenses, including legal
-fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
-LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE
-PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE THAT THE FOUNDATION, THE
-TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE
-LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
-INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH
-DAMAGE.
-
-1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a
-defect in this electronic work within 90 days of receiving it, you can
-receive a refund of the money (if any) you paid for it by sending a
-written explanation to the person you received the work from. If you
-received the work on a physical medium, you must return the medium
-with your written explanation. The person or entity that provided you
-with the defective work may elect to provide a replacement copy in
-lieu of a refund. If you received the work electronically, the person
-or entity providing it to you may choose to give you a second
-opportunity to receive the work electronically in lieu of a refund. If
-the second copy is also defective, you may demand a refund in writing
-without further opportunities to fix the problem.
-
-1.F.4. Except for the limited right of replacement or refund set forth
-in paragraph 1.F.3, this work is provided to you 'AS-IS', WITH NO
-OTHER WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
-LIMITED TO WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PURPOSE.
-
-1.F.5. Some states do not allow disclaimers of certain implied
-warranties or the exclusion or limitation of certain types of
-damages. If any disclaimer or limitation set forth in this agreement
-violates the law of the state applicable to this agreement, the
-agreement shall be interpreted to make the maximum disclaimer or
-limitation permitted by the applicable state law. The invalidity or
-unenforceability of any provision of this agreement shall not void the
-remaining provisions.
-
-1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the
-trademark owner, any agent or employee of the Foundation, anyone
-providing copies of Project Gutenberg-tm electronic works in
-accordance with this agreement, and any volunteers associated with the
-production, promotion and distribution of Project Gutenberg-tm
-electronic works, harmless from all liability, costs and expenses,
-including legal fees, that arise directly or indirectly from any of
-the following which you do or cause to occur: (a) distribution of this
-or any Project Gutenberg-tm work, (b) alteration, modification, or
-additions or deletions to any Project Gutenberg-tm work, and (c) any
-Defect you cause.
-
-Section 2. Information about the Mission of Project Gutenberg-tm
-
-Project Gutenberg-tm is synonymous with the free distribution of
-electronic works in formats readable by the widest variety of
-computers including obsolete, old, middle-aged and new computers. It
-exists because of the efforts of hundreds of volunteers and donations
-from people in all walks of life.
-
-Volunteers and financial support to provide volunteers with the
-assistance they need are critical to reaching Project Gutenberg-tm's
-goals and ensuring that the Project Gutenberg-tm collection will
-remain freely available for generations to come. In 2001, the Project
-Gutenberg Literary Archive Foundation was created to provide a secure
-and permanent future for Project Gutenberg-tm and future
-generations. To learn more about the Project Gutenberg Literary
-Archive Foundation and how your efforts and donations can help, see
-Sections 3 and 4 and the Foundation information page at
-www.gutenberg.org Section 3. Information about the Project Gutenberg
-Literary Archive Foundation
-
-The Project Gutenberg Literary Archive Foundation is a non profit
-501(c)(3) educational corporation organized under the laws of the
-state of Mississippi and granted tax exempt status by the Internal
-Revenue Service. The Foundation's EIN or federal tax identification
-number is 64-6221541. Contributions to the Project Gutenberg Literary
-Archive Foundation are tax deductible to the full extent permitted by
-U.S. federal laws and your state's laws.
-
-The Foundation's principal office is in Fairbanks, Alaska, with the
-mailing address: PO Box 750175, Fairbanks, AK 99775, but its
-volunteers and employees are scattered throughout numerous
-locations. Its business office is located at 809 North 1500 West, Salt
-Lake City, UT 84116, (801) 596-1887. Email contact links and up to
-date contact information can be found at the Foundation's web site and
-official page at www.gutenberg.org/contact
-
-For additional contact information:
-
-    Dr. Gregory B. Newby
-    Chief Executive and Director
-    gbnewby@pglaf.org
-
-Section 4. Information about Donations to the Project Gutenberg
-Literary Archive Foundation
-
-Project Gutenberg-tm depends upon and cannot survive without wide
-spread public support and donations to carry out its mission of
-increasing the number of public domain and licensed works that can be
-freely distributed in machine readable form accessible by the widest
-array of equipment including outdated equipment. Many small donations
-($1 to $5,000) are particularly important to maintaining tax exempt
-status with the IRS.
-
-The Foundation is committed to complying with the laws regulating
-charities and charitable donations in all 50 states of the United
-States. Compliance requirements are not uniform and it takes a
-considerable effort, much paperwork and many fees to meet and keep up
-with these requirements. We do not solicit donations in locations
-where we have not received written confirmation of compliance. To SEND
-DONATIONS or determine the status of compliance for any particular
-state visit www.gutenberg.org/donate
-
-While we cannot and do not solicit contributions from states where we
-have not met the solicitation requirements, we know of no prohibition
-against accepting unsolicited donations from donors in such states who
-approach us with offers to donate.
-
-International donations are gratefully accepted, but we cannot make
-any statements concerning tax treatment of donations received from
-outside the United States. U.S. laws alone swamp our small staff.
-
-Please check the Project Gutenberg Web pages for current donation
-methods and addresses. Donations are accepted in a number of other
-ways including checks, online payments and credit card donations. To
-donate, please visit: www.gutenberg.org/donate
-
-Section 5. General Information About Project Gutenberg-tm electronic works.
-
-Professor Michael S. Hart was the originator of the Project
-Gutenberg-tm concept of a library of electronic works that could be
-freely shared with anyone. For forty years, he produced and
-distributed Project Gutenberg-tm eBooks with only a loose network of
-volunteer support.
-
-Project Gutenberg-tm eBooks are often created from several printed
-editions, all of which are confirmed as not protected by copyright in
-the U.S. unless a copyright notice is included. Thus, we do not
-necessarily keep eBooks in compliance with any particular paper
-edition.
-
-Most people start at our Web site which has the main PG search
-facility: www.gutenberg.org
-
-This Web site includes information about Project Gutenberg-tm,
-including how to make donations to the Project Gutenberg Literary
-Archive Foundation, how to help produce our new eBooks, and how to
-subscribe to our email newsletter to hear about new eBooks.
-
diff --git a/old/50696-0.zip b/old/50696-0.zip
deleted file mode 100644
index af876af..0000000
--- a/old/50696-0.zip
+++ /dev/null
diff --git a/old/50696-h.zip b/old/50696-h.zip
deleted file mode 100644
index e141de2..0000000
--- a/old/50696-h.zip
+++ /dev/null
diff --git a/old/50696-h/50696-h.htm b/old/50696-h/50696-h.htm
deleted file mode 100644
index 539bf3c..0000000
--- a/old/50696-h/50696-h.htm
+++ /dev/null
@@ -1,15522 +0,0 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
-    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
-
-<head>
-    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-    <meta http-equiv="Content-Style-Type" content="text/css" />
-    <title>
-      The Project Gutenberg ebook of Railway Construction, by William H. Mills.
-    </title>
-    <link rel="coverpage" href="images/cover.jpg"/>
-    <style type="text/css">
-
-body {
-    margin-left: 10%;
-    margin-right: 10%;
-}
-
-    h1,h2,h3,h4 {
-    text-align: center; /* all headings centered */
-    clear: both;
-}
-
-.no-break {page-break-before: avoid;} /* for epubs */
-/* also use div class="chapter" to avoid page breaks */
-
-.break {page-break-before: always;} /* for epubs */
-
-/* for justified text of frontispiece:*/
-span.captionleft { display:inline-block; text-align:left; width:50%; }
-span.captionright { display:inline-block; text-align:right; width:50%; }
-
-p {
-    margin-top: .75em;
-    text-align: justify;
-    margin-bottom: .75em;
-}
-
-p.hanging {margin-left: 1em;
-           text-indent: -1em;
-           margin-bottom: 0;}
-
-p.indenthanging {margin-left: 2em; /* for ads */
-                 text-indent: -1em;
-                 margin-top: 0;}
-
-p.indentwide {text-indent: 3em;
-              margin-top: -.75em;}
-
-.indent {margin-left: 2em;}
-
-.p2 {margin-top: 2em;}
-.p4 {margin-top: 4em;}
-.mt1 {margin-top: -.75em;}
-.right {text-align: right;}
-
-hr { /*default rule across entire width */
-    margin-top: .5em;
-    margin-bottom: .5em;
-    margin-left: auto;
-    margin-right: auto;
-    clear: both;
-}
-
- table {margin-left: auto;
-  margin-right: auto;
-  border-collapse: collapse;
-  margin-top: 1em;
-  margin-bottom: 2em;}
-
-th {border: solid black 1px;
-    text-align: center;}
-
-.noshrink {min-width: 2.5em;
-           text-align: right;}
-.nonshrink {min-width: 14em;   /* for handheld tables page 44 */
-            text-align: left}
-
-.maxwide {width: 4em;} /* for handheld tables page 44 */
-
- td.center {vertical-align: top; /* no box */
-  text-align: center;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: 2.25em;}
-
- td.centerstd {vertical-align: middle; /* with box */
-  text-align: center;
-  border: solid black 1px;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.centernobox {vertical-align: middle; /* no box */
-  text-align: center;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.leftstd {vertical-align: top; /* with box */
-  text-align: left;
-  border: solid black 1px;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.left {vertical-align: top; /* no box */
-  text-align: left;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.leftmid {vertical-align: middle; /* no box, hanging indent */
-  text-align: left;
-  text-indent: -1em;
-  padding-left: 1.25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.leftex {vertical-align: top; /* extra padding left */
-  text-align: left;
-  padding-left: .75em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.lefth {vertical-align: top; /* hanging indent with box */
-  text-align: left;
-  text-indent: -1em;
-  border: solid black 1px;
-  padding-left: 1.25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.lefthnobox {vertical-align: top; /* hanging indent */
-  text-align: left;
-  text-indent: -1em;
-  padding-left: 1.25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.leftb {vertical-align: bottom;
-  text-align: left;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.right {vertical-align: top; /* no box */
-  text-align: right;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.rightm {vertical-align: middle; /* no box */
-  text-align: right;
-  padding-left: .25em;
-  padding-right: .5em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.rightb {vertical-align: bottom;
-  text-align: right;
-  padding-left: .25em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
- td.rightex {vertical-align: bottom; /* extra padding left for TOC */
-  text-align: right;
-  padding-left: 1.5em;
-  padding-right: .25em;
-  padding-bottom: .25em;
-  padding-top: .25em;}
-
-  table.a {text-decoration:none}
-
-/* the following to hand make boxes extending over more than one cell */
-  td.t  {border-top: solid thin;}
-  td.r  {border-right: solid thin;}
-  td.l  {border-left: solid thin;}
-  td.b  {border-bottom: solid thin;}
-
-/* for detail on page 229 */
-    .top_bottom {display: inline-block; vertical-align: middle;
-                 text-align: center; white-space: nowrap; padding: 0;
-                 font-size: .7em;}
-    .top {padding: 0 .25em; display: block; vertical-align: bottom;}
-    .bottom {padding: 0 .25em; display: block; vertical-align: top;}
-
-/* the following for tables to be split for handhelds but not screen */
-div.handheld {display: none;}
-div.nothandheld {display: block;}
-
-@media handheld {
-div.handheld {display: block;}
-div.nothandheld {display: none;}
-.hide {visibility: hidden;}
-a:link {text-decoration:none}
-table.a {text-decoration:none}
-}
-
-.anchorsize {font-size: smaller;}
-
-a:link {text-decoration:none} /* no UL of any links  useful for html accessibility*/
-
-a:visited {text-decoration:none}
-
-.ls {letter-spacing: .25em;  /* ls  and sc do not work in epubs; */
-     padding-left: .2em;}
-
-.hide {visibility: hidden;} /* to align centered numbers w/ leading zeros in tables */
-
-.pagenum {
-    position: absolute;
-    left: 92%;
-    font-size: 50%;
-    font-style: normal;
-    text-align: right;
-    color: #444;}
-
-.quotesign {
-  margin-left: 65%;
-  margin-top: 0em;
-}
-
-.center   {text-align: center;}
-
-.sc  {font-style: normal; font-variant: small-caps;}
-
-.u {text-decoration: underline;}
-
-.smaller {font-size: 90%;}
-
-.muchsmaller {font-size: 75%;} /* for all small caps inside span markup */
-
-.larger {font-size: 110%;}
-
-.muchlarger {font-size: 150%;}
-
-li {margin-left: 1em; /* secondary index lines indented */
-    text-indent:-1em;
-    list-style-type: none;}
-
-li.indent {text-indent: 5em;
-           list-style-type: none;}
-
-span.lock {white-space:nowrap;}
-
-/* Images */
-.figcenter   {
-    margin-left: auto;
-    margin-right: auto;
-    text-align: center;
-}
-
-/* remove bullets from index list */
-.none {list-style-type: none;}
-
-/* Transcriber notes */
-ins {text-decoration:none;
-     border-bottom: thin dotted gray;}
-
-.tnote {border: dashed .1em;
-        margin-left: 10%;
-        margin-right: 10%;
-        padding-bottom: .5em;
-        padding-top: .5em;
-        padding-left: .5em; padding-right: .5em;}
-
-    </style>
-  </head>
-
-<body>
-
-
-<pre>
-
-Project Gutenberg's Railway Construction, by William Hemmingway Mills
-
-This eBook is for the use of anyone anywhere in the United States and most
-other parts of the world at no cost and with almost no restrictions
-whatsoever.  You may copy it, give it away or re-use it under the terms of
-the Project Gutenberg License included with this eBook or online at
-www.gutenberg.org.  If you are not located in the United States, you'll have
-to check the laws of the country where you are located before using this ebook.
-
-
-
-Title: Railway Construction
-
-Author: William Hemmingway Mills
-
-Release Date: December 15, 2015 [EBook #50696]
-
-Language: English
-
-Character set encoding: UTF-8
-
-*** START OF THIS PROJECT GUTENBERG EBOOK RAILWAY CONSTRUCTION ***
-
-
-
-
-Produced by Chris Curnow, Carol Brown, and the Online
-Distributed Proofreading Team at http://www.pgdp.net (This
-file was produced from images generously made available
-by The Internet Archive)
-
-
-
-
-
-
-</pre>
-
-
-<!--001.png-->
-<div class="chapter">
-<p class="p4 center u"><i>LONGMANS’ CIVIL ENGINEERING SERIES</i></p>
-
-<h1>RAILWAY CONSTRUCTION</h1>
-</div><!--end title page-->
-
-<!--002.png-->
-<div class="chapter"><!--begin book adverts-->
-
-<p class="p4 center larger">LONGMANS’</p>
-
-<p class="center"><strong>CIVIL ENGINEERING SERIES</strong></p>
-
-<p class="p2 hanging">NOTES ON DOCKS AND DOCK CONSTRUCTION.</p>
-
-<p class="mt1 indenthanging">By <span class="sc">C. Colson</span>, C.B., M.Inst.C.E., Deputy Civil Engineer-in-Chief,
-Loan Works, Admiralty. With 365 Illustrations. Medium <abbr title="octavo">8vo</abbr>, 21<i class="money"><abbr title="shillings">s.</abbr></i>
-<i>net.</i></p>
-
-<p class="hanging">CALCULATIONS IN HYDRAULIC ENGINEERING:
-A Practical Text-Book for the Use of Students, Draughtsmen, and
-Engineers.</p>
-
-<p class="indenthanging">By <span class="sc">T. Claxton Fidler</span>, M.I.C.E., Professor of Engineering,
-University College, Dundee.</p>
-
-<p class="indenthanging">Part I. Fluid Pressure and the Calculation of its Effects in Engineering
-Structures. With numerous Illustrations and Examples. Medium <abbr title="octavo">8vo</abbr>,
-6<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> <i>net.</i></p>
-
-<p class="indenthanging">Part II. Calculations in Hydro-Kinetics. With numerous Illustrations and
-Examples. Medium <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> <i>net.</i></p>
-
-<p class="hanging">NOTES ON CONSTRUCTION IN MILD STEEL:</p>
-
-<p class="indenthanging">Arranged for the Use of Junior Draughtsmen in the Architectural and
-Engineering Professions. With 425 Illustrations from Working Drawings,
-Diagrams and Tables. By <span class="sc">Henry Fidler</span>, M.I.C.E. Medium <abbr title="octavo">8vo</abbr>, 16<i class="money"><abbr title="shillings">s.</abbr></i>
-<i>net.</i></p>
-
-<p class="hanging">RAILWAY CONSTRUCTION.</p>
-
-<p class="indenthanging">By <span class="sc">W. H. Mills</span>, M.I.C.E., Engineer-in-Chief, Great Northern
-Railway of Ireland. With 516 Illustrations. Medium <abbr title="octavo">8vo</abbr>, 18<i class="money"><abbr title="shillings">s.</abbr></i>
-<i>net.</i></p>
-
-<p class="hanging">PRINCIPLES AND PRACTICE OF HARBOUR CONSTRUCTION.</p>
-
-<p class="indenthanging">By <span class="sc">William Shield</span>, F.R.S.E., M.Inst.C.E., and Executive Engineer,
-National Harbour of Refuge, Peterhead, N.B. With 97 Illustrations. Medium
-<abbr title="octavo">8vo</abbr>, 15<i class="money"><abbr title="shillings">s.</abbr></i> <i>net.</i></p>
-
-<p class="hanging">CIVIL ENGINEERING AS APPLIED IN CONSTRUCTION.</p>
-
-<p class="indenthanging">By <span class="sc">Leveson Francis Vernon-Harcourt</span>, M.A., M.Inst.C.E. With 368
-Illustrations. Medium <abbr title="octavo">8vo</abbr>, 14<i class="money"><abbr title="shillings">s.</abbr></i> <i>net.</i></p>
-
-<p class="hanging">SANITARY ENGINEERING WITH RESPECT TO WATER-SUPPLY AND SEWAGE DISPOSAL.</p>
-
-<p class="indenthanging">By <span class="sc">Leveson Francis Vernon-Harcourt</span>, M.A., M.Inst.C.E. With 287
-Illustrations. Medium <abbr title="octavo">8vo</abbr>, 14<i class="money"><abbr title="shillings">s.</abbr></i> <i>net.</i></p>
-
-<p class="hanging">TIDAL RIVERS: their (1) Hydraulics, (2) Improvement, (3) Navigation.</p>
-
-<p class="indenthanging">By <span class="sc">W. H. Wheeler</span>, M.Inst.C.E. With 75 Illustrations. Medium <abbr title="octavo">8vo</abbr>,
-16<i class="money"><abbr title="shillings">s.</abbr></i> <i>net.</i></p>
-
-<p class="p2 center ls">LONGMANS, GREEN, AND CO.</p>
-
-<p class="center">LONDON, NEW YORK, BOMBAY, AND CALCUTTA</p>
-</div><!--end adverts-->
-<!--003.png--><!--004.png-->
-
-<div class="break p4 figcenter" style="width: 500px">
- <img src="images/frontis.jpg"
- width="auto" height="100%"
- alt="Illustration: KINSUA VIADUCT, ERIE RAILWAY, U.S.A."
- />
- <p><span class="captionleft"><i>Frontispiece.</i>]</span><span class="captionright">[<i>See <a href="#Page_97">p. 97</a>.</i></span></p>
- <p class="center">KINSUA VIADUCT, ERIE RAILWAY, U.S.A.</p>
-</div>
-
-<!--005.png-->
-
-<div class="chapter">
-
-<p class="p4 u"><i>LONGMANS’ CIVIL ENGINEERING SERIES</i></p>
-
-<p class="muchlarger center">RAILWAY CONSTRUCTION</p>
-
-
-<p class="p4 center smaller">BY</p>
-
-<h2 class="no-break">WILLIAM HEMINGWAY MILLS, <span class="sc">M.Inst.C.E.</span></h2>
-
-<p class="center muchsmaller">PAST PRESIDENT OF THE INSTITUTION OF CIVIL ENGINEERS OF IRELAND, AND<br />
-ENGINEER-IN-CHIEF OF THE GREAT NORTHERN<br />
-RAILWAY OF IRELAND</p>
-
-<div class="figcenter">
- <img src="images/logo.jpg"
- width="35%" height="auto"
- alt="Illustration: printer's logo"
- title="Printer's logo"
- />
-</div>
-
-<p class="center"><i>WITH ILLUSTRATIONS</i></p>
-
-<p class="p2 center smaller">FOURTH IMPRESSION</p>
-
-<p class="p2 center"><span class="ls">LONGMANS, GREEN, AND CO.</span></p>
-<p class="mt1 center">39 PATERNOSTER ROW, LONDON<br />
-NEW YORK, BOMBAY, AND CALCUTTA<br />
-1910</p>
-
-<p class="center smaller"><i>All rights reserved</i></p>
-</div><!--end of title page-->
-<!--006.png--><!--007.png-->
-
-<div class="chapter"><!--begin preface-->
-<h3 class="p4">PREFACE</h3>
-
-<p class="p2">The construction and maintenance of a railway calls for the
-application of so many branches of engineering that several volumes
-would be required to do ample justice to a subject so comprehensive
-and ever-extending. To avoid attempting so wide a range, the object of
-the following pages has been to describe briefly some of the
-recognized leading features which regulate railway construction, and
-to assist the explanation with sketches of works selected from actual
-practice.</p>
-
-<p>Where the number of existing good examples is legion, it is somewhat
-difficult to make a choice for illustration, and the course adopted
-has been to select such samples of structures as appear best to
-elucidate in a simple manner the different types of work under
-consideration.</p>
-
-<p>In the drawings and diagrams many important minor details are
-necessarily omitted, partly to avoid complexity, but principally to
-leave more prominent the leading features of the particular piece of
-work referred to in the description. Some of the sketches of the large
-span bridges and large span roofs are only shown in outline; but, as
-their principal dimensions are given, a general idea can be obtained
-of their actual proportions.</p>
-
-<p>No allusion is made to the requisite strengths of the various
-structures described, nor to the necessary dimensions of the materials
-used in their construction, as this would necessitate the introduction
-of a vast amount of mathematical formulæ which does not come under the
-province of the object in view, and which the engineer has already at
-command from his training and works of reference.</p>
-
-<p>Neither is any mention made as to the probable cost of the
-<!--008.png-->
-different
-works of construction, as these must always vary to a very large
-extent, according to the locality, facility of supply, and current
-prices of materials.</p>
-
-<p>Every railway scheme which is the outcome of public enterprise has its
-commercial aspect and influence. The large sums to be invested in its
-construction are expected to yield permanent and increasing returns,
-and this desirable end can only be attained where there is thorough
-efficiency in works and equipment, and a full compliance with those
-national regulations which control matters connected with public
-safety. The correct dealing with the technical requirements and
-structural features of the undertaking must always precede all other
-considerations, as the constituted authorities will exact a proper
-fulfilment of all the statutory obligations, regardless of the
-prospective remuneration to the promoters. A stroke of the pen may
-change a train-service, or alter the rates and tariffs, but a
-modification in the works of construction arising out of errors or
-oversight, would entail a heavy expenditure and tedious delay. The
-essential point of every railway undertaking must be its suitability
-and completeness in every respect for the duty for which it is
-intended.</p>
-
-<p>Notes of what has been done are always valuable for consideration and
-comparison, and that the following brief description and sketches may
-be found useful for reference, is the earnest wish of the writer.</p>
-
-<p class="quotesign">W. H. MILLS,<br />
-&emsp;&emsp;<span class="sc">M.Inst.C.E.</span></p>
-</div><!--end of preface-->
-<!--009.png-->
-
-<div class="chapter">
-<p class="p4 center larger"><a name="top"></a><span class="ls">CONTENTS</span></p>
-
-<table summary="table of contents">
-
-<tr><td colspan="2" class="right"><span class="muchsmaller">PAGE</span></td>
-</tr>
-<tr><td class="center" colspan="2">CHAPTER I.</td>
-</tr>
-
-<tr><td class="lefthnobox">Location of a line of railway&mdash;Government regulations&mdash;Questions for consideration
-in connection with gauge, gradients, and curves</td><td class="rightex noshrink"><a href="#Page_1">1</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER II.</td>
-</tr>
-
-<tr><td class="lefthnobox">Works of construction: Earthworks, Culverts, Bridges, Foundations, Screw
-piles, Cylinders, Caissons, Retaining walls, and Tunnels</td><td class="rightex noshrink"><a href="#Page_60">60</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER III.</td>
-</tr>
-
-<tr><td class="lefthnobox">Permanent way&mdash;Rails&mdash;Sleepers&mdash;Fastenings&mdash;and Permanent-way laying</td><td class="rightex noshrink"><a href="#Page_182">182</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER IV.</td>
-</tr>
-
-<tr><td class="lefthnobox">Stations: Station Buildings, Roofs, Lines, and Sidings</td><td class="rightex noshrink"><a href="#Page_248">248</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER V.</td>
-</tr>
-
-<tr><td class="lefthnobox">Sorting-sidings&mdash;Turn-tables&mdash;Traversers&mdash;Water-Tanks and Water-Columns</td><td class="rightex noshrink"><a href="#Page_285">285</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER VI.</td>
-</tr>
-
-<tr><td class="lefthnobox">Comparative Weights of some Types of Modern Locomotives</td><td class="rightex noshrink"><a href="#Page_304">304</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER VII.</td>
-</tr>
-
-<tr><td class="lefthnobox">Signals&mdash;Interlocking&mdash;Block Telegraph and Electric Train Staff Instruments</td><td class="rightex noshrink"><a href="#Page_313">313</a></td>
-</tr>
-
-<tr><td class="center" colspan="2">CHAPTER VIII.</td>
-</tr>
-
-<tr><td class="lefthnobox">Railways of different ranks&mdash;Progressive improvements&mdash;Growing tendency
-for increased speeds, with corresponding increase in weight of permanent
-way and rolling-stock&mdash;Electricity as a motive-power</td><td class="rightex noshrink"><a href="#Page_348">348</a></td>
-</tr>
-
-<tr><td class="left"><br /><span class="sc">Index</span></td><td class="rightex noshrink"><a href="#Page_361">361</a></td>
-</tr>
-</table>
-</div><!--end contents-->
-
-<div class="chapter"><!--010.png--><!--011.png--><a name="Page_1" id="Page_1"></a><span class="pagenum">[Pg 1]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER I.</h3>
-
-<p class="center smaller">Location of a line of railway&mdash;Government regulations&mdash;Questions for
-consideration in connection with gauge, gradients, and curves.</p>
-
-<p class="p2"><strong>Location.</strong>&mdash;The locating of a line of railway, or the determination
-of its exact route, is influenced by many circumstances. In a rich
-country, with thickly populated districts and large industrial
-enterprises, there are towns to be served, manufacturing centres to be
-accommodated, and harbours to be brought into connection; while, at
-the same time, there may be important estates which must be avoided
-and private properties which must not be entered. Each point will
-present its own individual claim for consideration when selecting the
-route which promises the greatest amount of public convenience and
-commercial success.</p>
-
-<p>In new countries&mdash;in our colonies, and especially out in the far west
-of Canada and the United States&mdash;railways have to be laid out in
-almost uninhabited districts, where there is but little population or
-commerce to serve, and where the principal object is to obtain the
-best and most direct route through the vast territories, leaving
-colonists and settlers to choose afterwards the most convenient sites
-for towns and villages. Untrammelled by the network of public and
-private roads and properties which are met with at home, it might
-appear that the locating of such a line would be comparatively light;
-but even in such countries, which at first sight seem to present
-unlimited freedom for selecting a route, much can be done, and should
-be done, by taking a course through those plains and districts which
-possess the best natural resources for future agricultural,
-manufacturing, or mineral development.</p>
-
-<p>In addition to the motives of convenience and policy, the route of
-every line of railway must be influenced by the natural features of
-the country&mdash;the mountains, valleys, and rivers. These physical
-obstacles are in some cases on such an enormous
-<!--012.png--><a name="Page_2" id="Page_2"></a><span class="pagenum">[Pg 2]</span>
-scale as to compel
-long detours in the formation of a more suitable opening; and in
-others, although the difficulties are not insurmountable, they may
-involve works of great magnitude and expense.</p>
-
-<p>In a comparatively rich country, with a prospect of large and
-remunerative traffic, a succession of heavy works, bridges, and
-tunnels may be admissible and expedient; but in new countries economy
-of outlay has to be considered, and costly works avoided as much as
-possible.</p>
-
-<p>Every one of the heavy works on a line, whether lofty bridges, long
-viaducts, or costly tunnels, not only enormously increase the original
-expenditure of the undertaking, but also entail large annual outlay in
-the necessary constant supervision and maintenance.</p>
-
-<p>Each particular scheme will have to be discussed on its own individual
-merits. The heavy, high-speed passenger traffic line will suggest
-light gradients and easy curves, while on secondary lines and in
-thinly populated districts it may be prudent, for the sake of economy,
-to introduce sharper curves and heavier gradients. Even in the latter
-case, and especially in new countries, it is well to keep in view the
-future possibilities of the undertaking. The steeper the gradients,
-the greater the cost and time in working the traffic, and if there is
-every probability of early and large development, the prospective
-increase may warrant an additional outlay in the original
-construction.</p>
-
-<p>Large, open plains and wide valleys of important rivers generally
-afford ample latitude for the selection of a suitable route, and, by
-taking advantage of the gradations of altitude, a favourable course
-may be adopted without incurring excessive gradients. When traversing
-moderately hilly districts, some low ridge or opening may be found,
-which may form a pass from the one side to the other, and the line may
-be laid out for a long distance to lead gradually up to the highest
-point. But when a route has to be laid out over some of those lofty
-mountain ranges which are met with abroad, the locating of a suitable
-line, or of any line, becomes particularly intricate and difficult. A
-comparatively low ridge may be found possessing features in favour of
-the project, but the question will be how to reach that point. The
-nearer the summit of these high mountains, the more precipitous the
-sides; no one slope can
-<!--013.png--><a name="Page_3" id="Page_3"></a><span class="pagenum">[Pg 3]</span>
-be found sufficiently long and uniform to
-permit a practical direct ascent, and the only way out of the
-difficulty is to make a series of detours along the various spurs of
-the mountains to gain length to overcome the height. Each detour has
-to be the subject of most careful study. Forming part of a long series
-of ascending gradients, it has to follow the winding of the
-mountain-side, must be laid out to be always gaining in height, and
-will comprise important works, many of them of considerable extent,
-necessary for protection against the floods and atmospherical changes
-of the locality.</p>
-
-<p>In these higher altitudes nature is met with on the grandest and most
-rugged scale. Deep gorges, wide ravines, and almost perpendicular
-rocks form the pathway along which the line must be carried, and the
-skill of the engineer is taxed to the utmost to select a course which
-shall comprise a minimum of the works of magnitude. Mile after mile of
-line must be laid out in almost inaccessible places, loose or broken
-rocks must be avoided, a firm foundation must be obtained at all
-points skirting high ledges, and ample provision must be made for
-those mountain torrents which rise so suddenly, and are liable to
-sweep away all before them.</p>
-
-<p>Many grand examples of these detour lines are in existence in
-different parts of the world, and the traveller passing over them can
-realize the difficulties that had to be encountered, and the masterly
-manner in which they have been overcome.</p>
-
-<p>Before proceeding to carry out the works of any line of railway, it is
-necessary to prepare a complete plan and section of the line, showing
-the route to be followed and the position of the various curves,
-gradients, and principal works. Within certain limits, the course of
-the line may have to be slightly modified as the work proceeds, in
-consequence of ground turning out unfavourable, river-crossings
-treacherous, or of sites involving so many contingent alterations that
-it is found better to avoid them altogether. The route should,
-however, be so carefully studied out before completing the final plan
-and section, as to leave only minor deviations of line and level to be
-dealt with in the actual carrying out of the work.</p>
-
-<p>The promoters of lines in the United Kingdom obtain valuable
-assistance from the ordnance maps, which give full and reliable
-information regarding the position of all roads, rivers, and
-boundaries of counties, parishes, and townlands. In
-<!--014.png--><a name="Page_4" id="Page_4"></a><span class="pagenum">[Pg 4]</span>
-many parts abroad
-local maps are scarce, and not always accurate, and engineers have to
-depend principally on their own surveys, and rely upon the resident
-local authorities for any particulars as to divisions of territory. On
-some of our great colonial plains, and out in the far west of America,
-a line may be laid out for miles without a single landmark to localize
-it on a plan; but careful setting out, and the relative levels of the
-ground and gradients, as shown on the section, will always indicate
-the correct position of any portion of the work.</p>
-
-<p>Both at home and abroad complete plans and sections of any proposed
-railway must be deposited with the proper Government authorities, and
-must be approved and sanctioned by them before permission can be
-obtained to proceed with the works.</p>
-
-<p>The regulations regarding the scale and general arrangement of these
-plans and sections vary in different countries, and are subject to
-modification from time to time.</p>
-
-<p>Each country has its own special enactments relative to the method of
-dealing with roads, rivers, streams, and public and private property
-proposed to be interfered with in the construction of any line, and a
-knowledge of these is absolutely necessary for the promoters of any
-new scheme, inasmuch as some of the requirements may, in certain
-instances, influence the precise route to be selected.</p>
-
-<p>The English Government has passed several Acts of Parliament setting
-forth the general conditions which must be complied with in the
-construction of any railway in the United Kingdom. These conditions,
-or standing orders, relate both to the acquirement of land and
-property, the size and description of works for public or private
-accommodation, and the inspection and official approval of the
-undertaking when completed. These fixed regulations are alike valuable
-to the promoters and to the public; the former are informed of the
-principal points with which the scheme must conform, and the latter
-know the limit of their legal demands.</p>
-
-<p>No line of railway, or extension of any railway, will obtain
-Parliamentary sanction unless it can be satisfactorily proved in the
-outset, that its construction would be of public advantage. This point
-is of paramount importance, and due weight must be given to it when
-preparing to refute the evidence of opponents to the scheme.</p>
-
-<div class="figcenter"><!--015.png--><a name="Page_5" id="Page_5"></a><span class="pagenum">[Pg 5]</span>
- <a name="fig1"></a>
- <img src="images/i005.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 1"
- title="Figure 1"
- />
-</div>
-
-<p><!--016.png--><a name="Page_6" id="Page_6"></a><span class="pagenum">[Pg 6]</span>
-When conceding the right to make any railway, Parliament grants with
-it the power to purchase lands or property compulsorily, or by
-agreement, to change and divert roads and streams in the manner shown
-on the deposited plans, and to construct all necessary bridges and
-works in accordance with the standing orders, or such modifications of
-them as may be approved by the Board of Trade.</p>
-
-<p>The standing orders, or Government regulations, are very
-comprehensive, and include much detailed information on all questions
-likely to arise. The following brief summary of some of the principal
-orders relating to deposited plans, and works of construction, will be
-found useful for reference.</p>
-
-<p class="p2"><strong>Extract from Government Standing Orders and Regulations.</strong>&mdash;All
-plans and sections relative to proposed new railways must be lodged
-with the constituted Government Authorities on or before November 30.</p>
-
-<p>Every deposited plan must be drawn to a scale of not less than four
-inches to a mile, and must describe the centre line, or situation of
-the work (no alternative line being allowed), and must show all lands,
-gardens, or buildings within the limits of deviation, each one being
-numbered with a reference number, and where powers to make lateral
-deviations are applied for, the limits of such deviation must be
-marked on the plan.</p>
-
-<p>Unless the whole of such plan be drawn to a scale of not less than 400
-feet to an inch, an enlarged plan must be drawn to that scale of every
-building and garden within the limits of deviation.</p>
-
-<p>The Railway Clauses Act limits the extent of deviation to 100 yards on
-each side of the centre line in the country, and 10 yards on each side
-of the centre line in towns or villages.</p>
-
-<p>The distances must be marked on the plan in miles and furlongs from
-one of the termini.</p>
-
-<p>The radius of every curve not exceeding one mile must be marked on the
-plan in furlongs and chains.</p>
-
-<p>In tunnels the centre line must be dotted, but no work must be shown
-as tunnelling, in the making of which it is necessary to cut through,
-or remove the surface soil. If it is intended to divert or alter any
-public road, navigable river, canal, or railway, the course and extent
-of such diversion, etc., shall be marked on the plan.</p>
-
-<div class="figcenter">
- <a name="fig2"></a>
- <img src="images/i007.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 2"
- title="Figure 2"
- />
-</div>
-
-<p>When a railway is to form a junction with an existing
-<!--017.png--><!--018.png--><a name="Page_8" id="Page_8"></a><span class="pagenum">[Pg 8]</span>
-railway, the course of
-such existing railway must be shown on the plan for a distance of 800
-yards on each side of the proposed junction. In the case of Bills for
-constructing subways, the plans and sections must indicate the height
-and width of such subway, and the nature of the approaches by which it
-is proposed to afford access to such subway.</p>
-
-<p>The Book of Reference must contain the names of all owners, lessees,
-and occupiers of all lands and houses of every parish within the
-limits of deviation.</p>
-
-<p>The numbers on the Book of Reference must correspond with the numbers
-on the plan, and opposite to each number must be entered a brief
-description of the property, whether field, garden, house, road,
-railway, or river. It is intended that the plan and Book of Reference
-together, shall afford ample information to enable all parties
-interested to ascertain to what extent their property will be affected
-by the proposed undertaking.</p>
-
-<p>The section must be drawn to the same horizontal scale as the plan,
-and to a vertical scale of not less than 100 feet to an inch, and must
-show the level of the ground, the level of the proposed work, the
-height of every embankment, the depth of every cutting, and a
-horizontal datum line which shall be referred to some fixed point,
-near one of the termini.</p>
-
-<p>In every section of a railway, the line of railway marked thereon must
-correspond with the upper surface of the rails.</p>
-
-<p>Distances on the datum line must be marked in miles and furlongs to
-correspond with those on the plan; a vertical measure from the datum
-line to the line of the railway must be marked in feet and decimals at
-the commencement and termination of the railway, and at each change of
-gradient, and the rate of inclination between such vertical measures
-must also be marked.</p>
-
-<p>Wherever the line of railway crosses any public carriage road,
-navigable river, canal, or railway, the height of the railway over, or
-depth beneath the surface thereof, and the height and span of every
-arch by which the railway will be carried over the same, must be
-marked in figures.</p>
-
-<div class="figcenter">
- <a name="fig3"></a>
- <img src="images/i009.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 3"
- title="Figure 3"
- />
-</div>
-
-<p>In the case of a public road level crossing, it must be described on
-the section, and it must also be stated if such level will be
-unaltered. If any alteration be intended in the level of any canal,
-public road, or railway which will be crossed by the intended line of
-railway, the same must be stated on the section and cross-sections to
-a horizontal scale of not less than 330 feet
-<!--019.png--><!--020.png--><a name="Page_10" id="Page_10"></a><span class="pagenum">[Pg 10]</span>
-to an inch, and a vertical
-scale of not less than 40 feet to an inch must be added, which must
-show the present surface of such road, canal, etc., and the intended
-surface thereof when altered, and the greatest of the present and
-intended rates of inclination marked in figures, such cross-sections
-to extend 200 yards on each side of the centre line of railway.</p>
-
-<p>Wherever the height of any embankment, or depth of any cutting, shall
-exceed 5 feet, the extreme height over or depth beneath the surface of
-the ground must be marked in figures upon the section.</p>
-
-<p>All tunnels and viaducts must be shown on the section.</p>
-
-<p>At a junction with an existing railway, the gradient of such existing
-railway must be shown on the section on the same scale as the general
-section for a distance of 800 yards on each side of the point of
-junction.</p>
-
-<p>Where the level of any turnpike or public road has to be altered in
-making any railway, the gradient of any altered road need not be
-better than the mean inclination of the existing road within a
-distance of 250 yards of the point of crossing the railway; but where
-the existing roads have easy gradients, then the gradients of the
-altered roads, whether carried over, or under, or on the level with
-the railway, must not be steeper than 1 in 30 for a turnpike road, 1
-in 20 for a public carriage road, 1 in 16 for a private or occupation
-road.</p>
-
-<p>A good and sufficient fence, 4 feet high at least, shall be made on
-each side of every bridge, and fences 3 feet high on the approaches.</p>
-
-<p>The application to cross any public road on the level must be reported
-upon by one of the officers of the Board of Trade, and special
-permission for the work must be embodied in the Act.</p>
-
-<p>Not more than 20 houses of the labouring classes may be purchased in
-any city or parish in England, Scotland, and Wales, or more than 10
-such houses in Ireland, until approval has been obtained to a scheme
-for building such houses in lieu thereof as the authorities may deem
-necessary.</p>
-
-<p>Every bridge (unless specially authorized to be otherwise) must
-conform with the following regulations:&mdash;
-
-A bridge over a turnpike road must have a clear span of 35 feet on the
-square between the abutments, with a headway, or height, of 16 feet
-for a width of 12 feet, as shown on <a href="#fig12">Fig. 12.</a></p>
-
-<div class="figcenter">
- <a name="fig4"></a>
- <img src="images/i011.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 4"
- title="Figure 4"
- />
-</div>
-
-<p>A bridge over a public road must have a clear span of 25 feet
-<!--021.png--><!--022.png--><a name="Page_12" id="Page_12"></a><span class="pagenum">[Pg 12]</span>
-on the
-square between the abutments, with a headway of 15 feet for a width of
-10 feet, as shown on <a href="#fig12">Fig. 13</a>.</p>
-
-<p>A bridge over a private or occupation road must have a clear span of
-12 feet on the square between the abutments, with a headway of 14 feet
-for a width of 9 feet, as shown on <a href="#fig12">Fig. 14</a>.</p>
-
-<p>Road bridges over the railway must have the same clear width between
-the parapets, measured on the square, as the widths prescribed for
-road bridges under the railway, or 35 feet for a turnpike road, 25
-feet for a public road, and 12 feet for private or occupation road.</p>
-
-<p>It is not compulsory, however, to construct the public road bridges
-over or under the railway of a greater width than the average
-available width of the existing roads within 50 yards of the point of
-crossing the railway, but in no case must a bridge have a less width
-than 20 feet. Should the narrow roads be widened at any future time,
-the railway company will be under the obligation to widen the bridges
-at their own expense to the extent of the statutory widths of 35 feet
-for a turnpike road, and 25 feet for a public road.</p>
-
-<p>Suitable accommodation works in the form of bridges, level crossings,
-gates, or other works, must be provided for the owners, or occupiers
-of lands, or properties intersected or affected by the construction of
-the railway; or payments may be made by agreement instead of
-accommodation works. All questions, or differences between the Railway
-Company, and the owners or occupiers of property affected, will be
-decided by the authorities duly appointed by the Government for the
-purpose.</p>
-
-<p>In constructing the railway, the Parliamentary plans and sections may
-be deviated from to the following <span style="white-space:nowrap;">extent:&mdash;</span></p>
-
-<p>The centre line may be deviated anywhere within the limits of
-deviation (100 yards on each side of the centre line in country, and
-10 yards each side in towns, or villages).</p>
-
-<p>Curves may be sharpened up to half a mile radius, and further, if
-authorized by the Board of Trade.</p>
-
-<p>A tunnel may be made instead of a cutting, and a viaduct instead of an
-embankment, if authorized by the Board of Trade.</p>
-
-<p>The levels may be deviated from to the extent of 5 feet in the
-country, and 2 feet in a town, or village, and various authorities
-have power to consent to further deviations.</p>
-
-<div class="figcenter">
- <a name="fig5"></a>
- <img src="images/i013.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 5"
- title="Figure 5"
- />
-</div>
-
-<p>Gradients may be diminished to any extent, gradients flatter than 1 in
-100 may be made steeper to the extent of 10 feet in a
-<!--023.png--><!--024.png--><a name="Page_14" id="Page_14"></a><span class="pagenum">[Pg 14]</span>
-mile, and
-gradients steeper than 1 in 100 may be made steeper to the extent of 3
-feet in a mile, or to such further extent as may be authorized by the
-Board of Trade.</p>
-
-<p>Suitable fences must be erected on each side of the line, to separate
-the land taken for the use of the railway from the adjoining lands not
-taken, and to protect such lands from trespass, or the cattle of the
-owners, or occupiers thereof from straying on to the railway.</p>
-
-<p>In addition to the Parliamentary plans, and sections, and Book of
-Reference, an estimate of the cost of each separate line, or branch,
-must be prepared as near to the following form as circumstances will
-permit.</p>
-
-<p class="p2 smaller">[Transcriber's Note: Searchable text of the following
-form can be found at the <a name="back"></a><a href="#estimateform">end</a> of the chapter.]</p>
-
-<div class="figcenter">
- <img src="images/estimate_form.jpg"
- width="auto" height="100%"
- alt="Illustration: Estimate form"
- title="Estimate form"
- />
-</div>
-
-<div class="p2 figcenter">
-<!--025.png--><a name="Page_15" id="Page_15"></a><span class="pagenum">[Pg 15]</span>
- <a name="fig6"></a>
- <img src="images/i015.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 6"
- title="Figure 6"
- />
-</div>
-
-<p><!--026.png--><a name="Page_16" id="Page_16"></a><span class="pagenum">[Pg 16]</span>
-The same details for each branch, and general summary of total cost.</p>
-
-<p>Every Railway Bill must be read twice, both in the House of Commons
-and in the House of Lords. A committee, duly appointed for each House,
-must report upon it, and if the reports from such committees be
-favourable, the Bill will be read a third time, and passed.</p>
-
-<p>When it has passed both Houses, the Bill receives the Royal Assent,
-and becomes law.</p>
-
-<p>The minimum scale of four inches to a mile for the plans is so very
-small that it is rarely, if ever, adopted. It would necessitate
-enlarged plans of so many portions to show clearly the property or
-buildings inside the limits of deviation, that in practice it is found
-expedient to make the plans to a much larger scale.</p>
-
-<p><a href="#fig1">Figs. 1</a> and <a href="#fig2">2</a> show a small portion of a Parliamentary plan and section
-drawn to the minimum scale allowed, with an enlargement of a small
-part to distinguish the houses clearly.</p>
-
-<p><a href="#fig3">Figs. 3</a> and <a href="#fig4">4</a> show a part of the same plan and section drawn to a
-scale of 400 feet to an inch, a scale which is very frequently
-adopted, and is sufficiently large to distinguish the buildings and
-small plots, except in closely populated districts. This scale also
-gives ample room for reference numbers.</p>
-
-<p>The Parliamentary plans and sections must be accurate in delineation,
-levels, and description. All property within the prescribed limits of
-deviation must be clearly shown, and the numbers and description on
-the plans and book of reference must be concise and complete, to
-enable the owners to ascertain to what extent they will be affected.
-In every place where it is proposed to interfere with any public
-highway, street, footpath, river or canal, the manner of such proposed
-alteration must be shown and described on both plan and section. The
-commencement and termination of every tunnel must be correctly
-indicated, and the length given on both plan and section. An omission
-of any of the above requirements might prove very detrimental to the
-scheme, and possibly result in the Bill being thrown out of Parliament
-for non-compliance with standing orders.</p>
-
-<div class="figcenter">
- <a name="fig7"></a>
- <img src="images/i017.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 7"
- title="Figure 7"
- />
-</div>
-
-<p>In carrying out the works the constructors have power to deviate the
-centre line either to the one side or the other, provided that such
-deviation will permit of the boundary of the works, or property to be
-acquired, to come within the limits
-<!--027.png--><!--028.png--><a name="Page_18" id="Page_18"></a><span class="pagenum">[Pg 18]</span>
-of deviation or property
-referenced, and they may also vary the levels of the line to the
-extent prescribed in the standing orders.</p>
-
-<p><a href="#fig5">Figs. 5</a> and <a href="#fig6">6</a> are parts of a Parliamentary plan and section showing
-alteration of a public road with an overline bridge&mdash;also a diversion
-of a small river to avoid two river bridges.</p>
-
-<p><a href="#fig7">Figs. 7</a> and <a href="#fig8">8</a> are parts of a Parliamentary plan and section showing a
-public road diverted and carried under the railway.</p>
-
-<p>A stipulated time is fixed in the Bill for the purchase of the
-property and construction of the line, and if this time be exceeded
-before the completion of the works, it will be necessary to obtain
-further Parliamentary powers for an extension of time.</p>
-
-<p>Every new railway, or extension of railway, in the United Kingdom,
-must be inspected, and certified, by one of the inspecting officers of
-the Board of Trade, previous to Government sanction being granted for
-its opening as a passenger line.</p>
-
-<p>To facilitate these inspections, and as a guide both to their own
-inspecting officers and the engineers in charge of the construction,
-the Board of Trade have issued a list of the principal requirements in
-connection with all new lines.</p>
-
-<p>The following is a copy of the list so far as relates to works of
-construction and <span style="white-space:nowrap;">signals:&mdash;</span></p>
-
-<p class="p2"><strong>Requirements of the Board of Trade.</strong>&mdash;1. The requisite apparatus
-for providing by means of the block telegraph system an adequate
-interval of space between following trains, and, in the case of
-junctions, between converging or crossing trains. In the case of
-single lines worked by one engine under steam (or two or more coupled
-together) carrying a staff, no such apparatus will be required.</p>
-
-<p>2. Home-signals and distant-signals for each direction to be fixed at
-stations and junctions, with extra signals for such dock, or bay
-lines, as are used either for the arrival, or for the departure of
-trains, and starting-signals for each direction, at all passenger
-stations which are also block posts. On passenger lines all cross-over
-roads and all connections for goods, or mineral lines, and sidings to
-be protected by home and distant signals, and as a rule at all
-important running junctions a separate distant-signal to be provided
-in connection with each home-signal.</p>
-
-<div class="figcenter">
- <a name="fig8"></a>
- <img src="images/i019.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 8"
- title="Figure 8"
- />
-</div>
-
-<p><i>Signals may be dispensed with on single lines under the following</i>
-<span style="white-space:nowrap;"><i>conditions</i>:&mdash;</span></p>
-
-<p class="indent">(<i>a</i>) <i>At all stations and siding connections upon a line</i>
-<!--029.png--><!--030.png--><a name="Page_20" id="Page_20"></a><span class="pagenum">[Pg 20]</span>
-<i>worked by
-one engine only (or two engines coupled together), carrying a staff,
-and when all points are locked by such staff.</i></p>
-
-<p class="indent">(<i>b</i>) <i>At any intermediate siding connection upon a line worked under
-the train staff and ticket system, or under the electric staff or tablet
-system, where the points are locked by the staff or tablet.</i></p>
-
-<p class="indent">(<i>c</i>) <i>At intermediate stations, which are not staff or tablet
-stations, upon a line worked under the electric staff or tablet
-system: Sidings, if any, being locked as in (b).</i></p>
-
-<p>3. The signals at junctions to be on separate posts, or on brackets;
-and the signals at stations, when there is more than one arm on one
-side of a post, to be made to apply&mdash;the first, or upper arm, to the
-line on the left, the second arm to the line next in order from the
-left, and so on; but in cases where the main, or more important line,
-is not the one on the left, separate signal-posts to be provided, or
-the arms to be on brackets. Distant-signals to be distinguished by
-notches cut out of the ends of the arms, and to be controlled by home
-or starting signals for the same direction when on the same post. A
-distant-signal arm must not be placed above a home or starting signal
-arm on the same post for trains going in the same direction.</p>
-
-<p>In the case of sidings, a low short arm and a small signal light,
-distinguishable from the arms or lights for the passenger lines, may
-be employed, but in such cases disc signals are, as a rule,
-preferable.</p>
-
-<p>Every signal arm to be so weighted as to fly to and remain at danger
-on the breaking at any point of the connection between the arm and the
-lever working it.</p>
-
-<p>4. On new lines worked independently, the front signal lights to be
-green for “all right,” and red for “danger;” the back lights (visible
-only when the signals are at “danger”) to be white.</p>
-
-<p><i>This requirement not to be obligatory in the case of new lines run
-over by trains of other companies using a different system of
-lights.</i></p>
-
-<p>5. Facing points to be avoided as far as possible, but when they
-cannot be dispensed with they must be placed as near as practicable to
-the levers by which they are worked or bolted. The limit of distance
-from levers working points to be 180 yards in the case of facing
-points, and 300 yards in the case of trailing points on the main line,
-or safety points of sidings.</p>
-
-<div class="figcenter">
- <a name="fig9"></a>
- <img src="images/i021.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 9"
- title="Figure 9"
- />
-</div>
-
-<p><!--031.png--><!--032.png--><a name="Page_22" id="Page_22"></a><span class="pagenum">[Pg 22]</span>
-In order to ensure that the points are in their proper position before
-the signals are lowered, and to prevent the signalman from shifting
-them while a train is passing over them, all facing points must be
-fitted with facing-point locks and locking-bars, and with means for
-detecting any failure in the connections between the signal-cabin and
-points. The length of the locking-bars to exceed the greatest
-wheel-base between any two pairs of wheels of the vehicles in use on
-the line, and the stock rails to be tied to gauge with iron or steel
-ties. All points, whether facing or trailing, to be worked or bolted
-by rods, and not by wires, and to be fitted with double
-connecting-rods.</p>
-
-<p>6. The levers by which points and signals are worked to be interlocked
-and, as a rule, brought close together, into the position most
-convenient for the person working them, in a signal-cabin or on a
-properly constructed stage. The signal-cabin to be commodious, and to
-be supplied with a clock, and with a separate block instrument for
-signalling trains on each line of rails. The point-levers and
-signal-levers to be so placed in the cabin that the signalman when
-working them shall have the best possible view of the railway, and the
-cabin itself to be so situated as to enable the signalman to see the
-arms and the lights of the signals and the working of the points. The
-back lights of the signal lamps to be made as small as possible,
-having regard to efficiency, and when the front lights are visible to
-the signalman in his cabin no back lights to be provided. The fixed
-lights in the signal-cabin to be screened off, so as not to be
-mistakable for the signals exhibited to control the running of trains.
-If, from any unavoidable cause, the arm and light of any signal cannot
-be seen by the signalman they must, as a rule, be repeated in the
-cabin.</p>
-
-<p>7. The interlocking to be so arranged that the signalman shall be
-unable to lower a signal for the approach of a train until after he
-has set the points in the proper position for it to pass; that it
-shall not be possible for him to exhibit at the same moment any two
-signals that can lead to a collision between two trains; and that,
-after having lowered the signals to allow a train to pass, he shall
-not be able to move any points connected with, or leading to, the line
-on which the train is moving. Points also, if possible, to be so
-interlocked as to avoid the risk of a collision.</p>
-
-<div class="figcenter">
-<!--033.png--><a name="Page_23" id="Page_23"></a><span class="pagenum">[Pg 23]</span>
- <a name="fig10"></a>
- <img src="images/i023.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 10"
- title="Figure 10"
- />
-</div>
-
-<p><!--034.png--><a name="Page_24" id="Page_24"></a><span class="pagenum">[Pg 24]</span>
-Home or starting signals next in advance of trading-points when
-lowered, to lock such points in either position, unless such locking
-will unduly interfere with the traffic.</p>
-
-<p>A distant signal must not be capable of being lowered unless the home
-and starting signals in advance of it have been lowered.</p>
-
-<p>8. Sidings to be so arranged that shunting operations upon them shall
-cause the least possible obstruction to the passenger lines.
-Safety-points to be provided upon goods and mineral lines and sidings,
-at their junctions with passenger lines, with the points closed
-against the passenger lines and interlocked with the signals.</p>
-
-<p>9. When a junction is situated near to a passenger station, the
-platforms to be so arranged as to prevent, as far as possible, any
-necessity for standing trains on the junction.</p>
-
-<p>10. The junctions of all single lines to be, as a rule, formed as
-double-line junctions.</p>
-
-<p>11. The lines of railway leading to the passenger platforms to be
-arranged so that the engines shall always be in front of the passenger
-trains as they arrive at and depart from a station; and so that, in
-the case of double lines, or of passing places on single lines, each
-line shall have its own platform. At terminal stations a double line
-of railway must not end as a single line.</p>
-
-<p>12. Platforms to be continuous, and not less than 6 feet wide for
-stations of small traffic, nor less than 12 feet wide for important
-stations. The descents at the ends of the platforms to be by ramps,
-and not by steps. Pillars for the support of roofs and other fixed
-works not to be less than 6 feet from the edges of the platforms. The
-height of the platforms above rail level to be 3 feet, save under
-exceptional circumstances, and in no case less than 2 feet 6 inches.
-The edges of the platforms to overhang not less than 12 inches. As
-little space as possible to be left between the edges of the platforms
-and those of the footboards on the carriages. Shelter to be provided
-on every platform, and conveniences where necessary. Names of stations
-to be shown on boards and on the platform lamps.</p>
-
-<p>13. When stations are placed on, or near a viaduct, or bridge under
-the railway, a parapet or fence on each side to be provided of
-sufficient height to prevent passengers, who may by mistake leave the
-carriages when not at the platform, from falling from the viaduct or
-bridge in the dark.</p>
-
-<div class="figcenter">
-<!--035.png--><a name="Page_25" id="Page_25"></a><span class="pagenum">[Pg 25]</span>
- <a name="fig11"></a>
- <img src="images/i025.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 11"
- title="Figure 11"
- />
-</div>
-
-<p><!--036.png--><a name="Page_26" id="Page_26"></a><span class="pagenum">[Pg 26]</span>
-14. Footbridges or subways to be provided for passengers to cross the
-railway at all exchange and other important stations. Staircases or
-ramps leading to or from platforms to be at no point narrower than at
-the top, and the available width to be in no case contracted by any
-erection or fixed obstruction whatever below the top.</p>
-
-<p>At all stations where crowding may be expected, the staircases or
-ramps to be of ample width, and barriers for regulating the entrance
-of the crowd at the top to be erected. If in such cases there are
-gates at the bottom, a speaking-tube or other means of communication
-between the top and bottom to be provided; and in all cases gates at
-the bottom of a staircase or ramp to open outwards. For closing the
-openings at the top, sliding bars or gates are considered best.</p>
-
-<p>The steps of staircases to be never less than 11 inches in the tread,
-nor more than 7 inches in the rise, and midway landings to be provided
-where the height exceeds 10 feet.</p>
-
-<p>Efficient handrails to be provided on both staircases and ramps, and
-in subways where ramps are used the inclination not to exceed 1 in 8.</p>
-
-<p>15. A clock to be provided at every station, in some conspicuous
-position visible from the platforms.</p>
-
-<p>16. No station to be constructed, and no siding to join a passenger
-line, on a steeper gradient than 1 in 260, except where it is
-unavoidable. When the line is double, and the gradient at a station or
-siding-junction is necessarily steeper than 1 in 260, and when danger
-is to be apprehended from vehicles running back, a catch-siding with
-points weighted for the siding, or a throw-off switch, to be provided
-to intercept runaway vehicles at a distance outside the home-signal
-for the ascending line, greater than the length of the longest train
-running upon the line.</p>
-
-<p>Under similar circumstances, when the line is single, provision for
-averting danger from runaway vehicles to be <span style="white-space:nowrap;">made&mdash;</span></p>
-
-<p class="hanging">(1) At a station in one of the following <span style="white-space:nowrap;">manners:&mdash;</span></p>
-
-<p class="indenthanging">(<i>a</i>) A second line to be laid down, a second platform to be
-     constructed, and a catch-siding or throw-off switch to be
-     provided on the ascending line inside the loop-points.</p>
-
-<p class="indenthanging">(<i>b</i>) A loop-line to be constructed lower down the incline than
-     the station platform with a similarly placed catch-siding or
-     throw-off switch.</p>
-
-<p><!--037.png--><a name="Page_27" id="Page_27"></a><span class="pagenum">[Pg 27]</span>
-(2) At a siding-junction in one of the following manners, except where
-it is possible to work the traffic with the engine at the lower end of
-a goods or mineral train, in which case an undertaking (see No. 35) to
-do so, given by the company, will be accepted as <span style="white-space:nowrap;">sufficient:&mdash;</span></p>
-
-<p class="indenthanging">(<i>a</i>) A similar loop to be constructed as in the case of a
-     station.</p>
-
-<p class="indenthanging">(<i>b</i>) Means to be provided for placing the whole train on sidings
-     clear of the main line before any shunting operations are
-     commenced.</p>
-
-<p>17. Engine-turntables of sufficient diameter to enable the longest
-engines and tenders in use on the line to be turned without being
-uncoupled to be erected at terminal stations and at junctions and
-other places at which the engines require to be turned, except in
-cases of short lines not exceeding 15 miles in length, where the
-stations are not at a greater distance than 3 miles apart, and the
-railway company gives an undertaking (see No. 35) to stop all trains
-at all stations. Care to be taken to keep all turntables at safe
-distances from the adjacent lines of rails, so that engines, waggons,
-or carriages, when being turned, may not foul other lines or endanger
-the traffic upon them.</p>
-
-<p>18. Cast-iron must not be used for railway under-bridges, except in
-the form of arched-ribbed girders, where the material is in
-compression.</p>
-
-<p>In a cast-iron arched bridge, or in the cast-iron girders of an
-over-bridge, the breaking weight of the girders not to be less than
-three times the permanent load due to the weight of the
-superstructure, added to six times the greatest moving load that can
-be brought upon it.</p>
-
-<p>In a wrought-iron or steel bridge, the greatest load which can be
-brought upon it, added to the weight of the superstructure, not to
-produce a greater strain per square inch on any part of the material
-than five tons where wrought-iron is used, or six tons and a half
-where steel is used.</p>
-
-<p>The engineer responsible for any steel structure to forward to the
-Board of Trade a certificate to the effect that the steel employed is
-either cast-steel, or steel made by some process of fusion,
-subsequently rolled or hammered, and of a quality possessing
-considerable toughness and ductility, together with a statement of all
-the tests to which it has been subjected.</p>
-
-<p><!--038.png--><a name="Page_28" id="Page_28"></a><span class="pagenum">[Pg 28]</span>
-19. In cases where bridges or viaducts are constructed wholly or
-partially of timber, a sufficient factor of safety, depending on the
-nature and quality of the timber, to be provided for.</p>
-
-<p><em>N.B.&mdash;The heaviest engines, boiler trucks, or travelling cranes in use
-on railways afford a measure of the greatest moving loads to which a
-bridge can be subjected. The above rules apply equally to the main
-transverse girders and rail-bearers.</em></p>
-
-<p>20. It is desirable that viaducts should, as far as possible, be
-wholly constructed of brick or stone, and in such cases they must have
-parapet walls on each side, not under 4 feet 6 inches in height above
-the rail level, and not less than 18 inches thick.</p>
-
-<p>Where it is not practicable to construct the viaducts of brick or
-stone, and iron or steel girders are made use of, it is considered
-best that in important viaducts the permanent way should be laid
-between the main girders. In all cases substantial parapets, with a
-height of not less than 4 feet 6 inches above rail-level must be
-provided by an addition to the girders, unless the girders themselves
-are sufficiently high. On important viaducts where the superstructure
-is of iron, steel, or timber, substantial outside wheel-guards to be
-fixed above the level of, and as close to the outer rails as possible,
-but not so as to be liable to be struck by any part of an engine or
-train running on the rails.</p>
-
-<p>In the construction of the abutments or piers which support the
-girders of high bridges and viaducts, cast-iron columns of small size
-must not be used.</p>
-
-<p>In all large structures a wind-pressure of 56 lbs. per square foot to
-be assumed for the purpose of calculation, which will be based on the
-rules laid down in the report, dated 30th May, 1881, of the committee
-appointed by the Board of Trade to consider the question of
-wind-pressure on railway structures.</p>
-
-<p>21. The upper surfaces of the wooden platforms of bridges and viaducts
-to be protected from fire.</p>
-
-<p>22. All castings for use in railway structures to be, where
-practicable, cast in a similar position to that which they are
-intended to occupy when fixed.</p>
-
-<p>23. The joints of rails to be secured by means of fish-plates, or by
-some other equally secure fastening. On main lines, and lines where
-heavy traffic may be worked at high speed, the chairs not to weigh
-less than 40 lbs.; but on branch lines, or
-<!--039.png--><a name="Page_29" id="Page_29"></a><span class="pagenum">[Pg 29]</span>
-lines on which the traffic
-is light, chairs weighing not less than 30 lbs. may be used.</p>
-
-<p>24. When chairs are used to support the rails they must be secured to
-the sleepers, at least partially, by iron spikes or bolts. With
-flat-bottomed rails, when there are no chairs, or with bridge rails,
-the fastenings at the joints, and at some intermediate places, to
-consist of fang or other through-bolts; and such rails, on curves with
-radii of 15 chains or less, to be tied to gauge by iron or steel ties
-at suitable intervals.</p>
-
-<p>25. In any curve where the radius is 10 chains or less, a check-rail
-to be provided.</p>
-
-<p>26. Diamond-crossings, as a rule, not to be flatter than 1 in 8.</p>
-
-<p>27. No standing work (other than a passenger platform) to be nearer to
-the side of the widest carriage in use on the line than 2 feet 4
-inches, at any point between the level of 2 feet 6 inches above the
-rails, and the level of the upper parts of the highest carriage doors.
-This applies to all arches, abutments, piers, supports, girders,
-tunnels, bridges, roofs, walls, posts, tanks, signals, fences, and
-other works, and to all projections at the side of a railway
-constructed to any gauge.</p>
-
-<p>28. The intervals between adjacent lines of rails, where there are two
-lines only, or between lines of rails and sidings, not to be less than
-6 feet. Where additional running lines of rails are alongside the main
-lines, an interval of not less than 9 feet 6 inches to be provided, if
-possible, between such additional lines and the main lines.</p>
-
-<p>29. At all level crossings of public roads, the gates to be so
-constructed that they may be closed either across the railway, or
-across the road at each side of the crossing, and a lodge, or, in the
-case of a station, a gatekeeper’s box, to be provided, unless the
-gates are worked from a signal cabin. The gates must not be capable of
-being opened at the same time for the road and the railway, and must
-be so hung as not to admit of being opened outwards towards the road.
-Stops to be provided to keep the gates in position across the road or
-railway. Wooden gates are considered preferable to iron gates, and
-single gates on each side to double gates. Red discs, or targets, must
-be fixed on the gates, with lamps for night use, and semaphore signals
-in one or both directions interlocked with the gates, may be required.
-At all level crossings of public roads or footpaths, a footbridge or a
-subway may be required.</p>
-
-<p><!--040.png--><a name="Page_30" id="Page_30"></a><span class="pagenum">[Pg 30]</span>
-At occupation and field crossings, the gates must be kept hung so as
-to open outwards from the line.</p>
-
-<p>30. Sidings connected with the main lines near a public road level
-crossing to be so placed that shunting may be carried on with as
-little interference as possible with the level crossing; and, as a
-rule, the points of the sidings to be not less than 100 yards from the
-crossing.</p>
-
-<p>31. At public road level crossings in or near populous places, the
-lower portions of the gates to be either close barred, or covered with
-wire netting.</p>
-
-<p>32. Mile posts, <a name="half"></a>half-mile, and quarter-mile posts, and gradient-boards
-to be provided along the line.</p>
-
-<p>33. Tunnels and long viaducts to be in all cases constructed with
-refuges for the safety of platelayers. On under-bridges without
-parapets, handrails to be provided. Viaducts of steel, iron, or timber
-to be provided with manholes or other facilities for inspection.</p>
-
-<p>34. Continuous brakes (in accordance with the Regulation of Railways
-Act of 1889), complying with the following requirements, to be
-provided on all trains carrying passengers, <span style="white-space:nowrap;"><abbr title="namely">viz.</abbr>&mdash;</span></p>
-
-<p class="indenthanging">(1) The brake must be instantaneous in action, and capable of
-     being applied by the engine-driver and guards.</p>
-
-<p class="indenthanging">(2) The brake must be self-applying in the event of any failure
-     in the continuity of its action.</p>
-
-<p class="indenthanging">(3) The brake must be capable of being applied to every vehicle
-     of the train, whether carrying passengers or not.</p>
-
-<p class="indenthanging">(4) The brake must be in regular use in daily working.</p>
-
-<p class="indenthanging">(5) The materials of the brake must be of a durable character,
-     and easily maintained and kept in order.</p>
-
-<p>35. Any undertaking furnished by a railway company to be under the
-seal, and signed by the chairman and secretary of the company.</p>
-
-<p class="p2"><strong>Recommendations as to the Working of Railways.</strong>&mdash;1. There should
-be a brake vehicle, with a guard in it, at or near the tail of every
-passenger train; this vehicle should be provided with a raised roof
-and extended sides, glazed to the front and back, and it should be the
-duty of the guard to keep a constant look-out from it along his train.</p>
-
-<p>2. All passenger carriages should be provided with continuous
-footboards, extending the whole length of each carriage
-<!--041.png--><a name="Page_31" id="Page_31"></a><span class="pagenum">[Pg 31]</span>
-and as far as
-the outer ends of the buffer castings. As passenger carriages pass
-from one company’s line to another’s, it is essential for the public
-safety that, although the widths of the carriages on the different
-lines may differ from each other, the widths across the carriages from
-the outside of the continuous footboard on one side, to the outside of
-the continuous footboard on the opposite side, should be identical for
-the carriages of all railway companies, so that the lines of rails may
-be laid at the proper distance from the edges of the passenger
-platforms.</p>
-
-<p>3. There should be efficient means of communication between the guard,
-or guards, of every passenger train and the engine-driver, and between
-the passengers and the servants of the company in charge of the train.</p>
-
-<p>4. The tyres of all wheels should be so secured as to prevent them
-from flying open when they are fractured.</p>
-
-<p>5. The engines employed with passenger trains should be of a steady
-description, with not less than six wheels, with the centre of gravity
-in front of the driving-wheels, and with the motions balanced. They
-should, as a rule, be run chimney in front.</p>
-
-<p>6. Records should be carefully kept of the work performed by the
-wearing parts of the rolling stock, to afford practical information in
-regard to them, and to prevent them from being retained in use longer
-than is desirable.</p>
-
-<p>7. In addition to the block-telegraph instruments, it is desirable
-that there should be speaking-instruments, or telephones, for
-communication between signalmen, and books for recording the running
-of the trains.</p>
-
-<p>8. When drovers or other persons are permitted to travel with goods or
-cattle trains, suitable vehicles should be provided for their
-accommodation.</p>
-
-<p>9. It is considered that, in fixed signals, the front lights should
-<span style="white-space:nowrap;">show&mdash;</span></p>
-
-<p class="indentwide">Green, for all right;</p>
-<p class="indentwide">Red, for danger;</p>
-
-<p class="mt1">and that back lights, visible only when the signals are at danger,
-should show white.</p>
-
-<p>10. Refuge sidings should be provided at all main-line stations where
-slow trains are liable to be shunted for fast trains to pass them. If
-at such stations it is impossible to
-<!--042.png--><a name="Page_32" id="Page_32"></a><span class="pagenum">[Pg 32]</span>
-provide refuge sidings, and slow
-trains have to be shunted from one main line to the other to allow of
-fast trains passing them, some simple arrangements should be supplied
-in the signal cabins to help to remind the signalman of the shunted
-train.</p>
-
-<p>11. Efficient means should be adopted to prevent the accidental
-opening of the doors of passenger trains.</p>
-
-<p class="p2">To carry out the undertaking, the engineer has to prepare working
-plans and sections to a somewhat larger scale than that adopted for
-the Government or Parliamentary plans, and on which must be marked the
-exact positions of the commencement of the curves, straight lines, and
-gradients. The sites of all the over and under bridges must be shown,
-and their angles of crossing noted. All road, river, or stream
-diversions must be indicated, so that the work in connection with them
-may be laid out on the ground. All culverts and drains must be marked,
-and their size, depth, and direction described. Public road
-level-crossings, and farm or occupation-road crossings, must be shown
-in their proper positions.</p>
-
-<p>The face-lines of the ends of all tunnels should be marked on the
-working plan and section, and the position of any shafts, which may be
-intended either for use in carrying on the work or for future
-ventilation.</p>
-
-<p>A considerable amount of investigation and negotiation will have to be
-entered into before the locating of the above works can be finally
-decided. The desire to meet the wishes and convenience of all parties
-interested must of necessity be controlled by the physical
-circumstances of each case; very little alteration can be made in the
-level of the rails, although some variation may be made in their
-position.</p>
-
-<p>When fixing the depths of culverts and drains, attention must be paid
-to any probable improvement in the drainage of the district, which
-might at some future time necessitate the deepening of such of the
-main culverts where the inverts had been laid too high.</p>
-
-<p>Unless all these details are determined, and shown on the
-working-plans before the works are commenced, there is the risk that
-embankments may have to be opened out to admit of bridges and
-culverts, and cuttings changed to permit of road diversions.</p>
-
-<p>The entire centre-line of railway must be carefully staked
-<!--043.png--><a name="Page_33" id="Page_33"></a><span class="pagenum">[Pg 33]</span>
-out by
-driving strong wooden pegs into the ground at the end of every chain
-length, and along the course of these pegs the longitudinal section
-must be taken. Three pegs, one on each side of the centre peg, are
-generally placed at the commencement and termination of the curves.
-When the longitudinal section has been plotted to scale, and the
-course of the gradients and level portions worked out and drawn on,
-then the heights of the ground level and formation level can be marked
-at each chain, and from them the depths of the cutting and the heights
-of the embankments can be ascertained and marked at each chain. In
-addition to the longitudinal section, it will be necessary to take a
-large number of transverse or cross sections at those pegs, or
-intermediate points, where the ground is at all side-lying or
-irregular. These cross-sections are necessary to determine the
-side-widths, or distances to outer edge of slopes in cuttings or
-embankments, and also to calculate the actual quantity of earthwork to
-be executed. For convenience in taking out the quantities, these
-cross-sections are generally plotted to a natural scale, that is to
-say, to the same scale horizontal as vertical, as shown in the example
-of cross-sections, <a href="#fig12">Figs. 15 to 24</a>. It is also necessary to obtain
-information, by boring or otherwise, as to the material of which the
-cuttings are composed, whether clay, gravel, or rock.</p>
-
-<p>In laying out lines through fairly level plains and populous
-districts, the absence of great natural obstacles will allow the
-engineer to carefully consider how far it may be prudent to diverge to
-the right or to the left, to accommodate towns and places which would
-be excluded by a more direct through route. There will be ample range
-for selection, and it will be rather the question of policy than
-compulsion which will guide him in the route to be taken.</p>
-
-<div class="figcenter">
- <a name="fig12"></a>
- <img src="images/i034.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 12 through 24"
- title="Figures 12 through 24"
- />
-</div>
-
-<p>When, however, the locating passes from the lower ground, away up
-amongst the hills and mountain ranges, it becomes an intricate study
-whether it will be possible to lay out any line at all which may
-possess gradients and curves practicable for railway working. The
-question of property, population, or convenience of access, is here no
-longer the controlling influence, but in its stead there are the far
-more formidable natural difficulties to be overcome in working out a
-trackway to the inevitable summit level. The chief endeavour will be
-to gain length, and so reduce as much as possible the steepness of the
-<!--044.png--><!--045.png--><a name="Page_35" id="Page_35"></a><span class="pagenum">[Pg 35]</span>
-gradients which at the best must necessarily be severe. In some of the
-earlier mountain lines constructed abroad the system of <em>zigzags</em> was
-introduced, as shown in <a href="#fig25">Fig. 25</a>. These <em>zigzags</em> were laid out on
-ruling gradients, one above the other, on the sides of the mountain
-slopes with pieces of level at the apices, <strong>A</strong>, <strong>B</strong>, and <strong>C</strong>, on which
-the engine could be changed from one end of the train to the other.
-Although feasible in principle, the system entailed considerable loss
-of time in train-working, and was not unattended with risk.</p>
-
-<p>The more modern and simple method of working out the same idea is to
-connect the main zigzag lines by curves or <em>spirals</em>, thus rendering
-the route continuous and unbroken. By this arrangement the heavy work
-and delay in starting or stopping the train at the apices, <strong>A</strong>, <strong>B</strong>,
-and <strong>C</strong>, as shown on <a href="#fig25">Fig. 25</a>, is avoided, and the train can proceed
-continuously on its circuitous journey. <a href="#fig25">Fig. 26</a> shows an instance of
-the zigzags and spirals, as carried out on an important railway
-abroad. To have made a direct line from <strong>D</strong> to <strong>E</strong>, the most difficult
-part of the route, would have involved a gradient of 1 in 11; but by
-constructing the spiral course, as shown, the length was more than
-trebled, and the gradient reduced to 1 in 35.</p>
-
-<p><a href="#fig25">Fig. 27</a> is another example of spiral zigzags in which advantage was
-taken to cut a short tunnel through a high narrow neck of rock at
-<strong>G</strong>, and then by skirting round the hill the line was taken over the
-top of the tunnel and along the side of the mountain to the summit tunnel
-at <strong>H</strong>. By this means the line from <strong>F</strong> to <strong>H</strong> was laid out to an
-average gradient of 1 in 42.</p>
-
-<p><a href="#fig25">Fig. 28</a> shows the Cumbres inclines on the Mexican Railway. The route
-had to be located through one of the rugged passes of the great Chain
-of the Andes, whose mountain-sides rise most abruptly from the lower
-plains, to the great upper-land plateau, some eight thousand feet
-above sea-level. The ground to be traversed was so steep and difficult
-that, even with the best available detours and greatest length that
-could be obtained, the result was an average continuous gradient of 1
-in 25 for 12 miles.</p>
-
-<div class="figcenter">
- <a name="fig25"></a>
- <img src="images/i036.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 25 through 29 "
- title="Figures 25 through 29"
- />
-</div>
-
-<p><a href="#fig25">Fig. 29</a> is a plan of part of the St. Gothard Railway, showing the
-principal tunnel 9¼ miles long, and some of the adjoining spiral
-tunnels. The long tunnel through the great Alpine barrier was the only
-means of forming a railway connection between the two points at Airolo
-and Goeschenen. Constructed
-<!--046.png--><!--047.png--><a name="Page_37" id="Page_37"></a><span class="pagenum">[Pg 37]</span>
-in a straight line, with easy gradients,
-falling towards the entrances, efficiency of drainage has been
-secured, and excessive strain on motive-power avoided. The approaching
-valleys on each side were in some places too irregular and broken to
-admit of zigzag loops, and the spiral tunnels were adopted instead.
-The enlarged plan of two of the spiral tunnels will explain the method
-of working. An ascending train enters the first tunnel at <strong>A</strong>, and
-after passing round almost an entire circle, on a rising gradient,
-emerges at a much higher level at the point <strong>B</strong>. Proceeding onward,
-the train enters the second tunnel at <strong>C</strong>, and after passing round a
-similar circle, on a rising gradient, comes out at a still higher
-point, <strong>D</strong>, and continues its course up the valley.</p>
-
-<p>The last five sketches illustrate some of the methods which have been
-adopted when constructing railways through some of the most difficult
-mountain ranges. They show what has been done, and may serve as guides
-in working out the location of a line in some hitherto unexplored
-region.</p>
-
-<p class="p2"><strong>Gauge.</strong>&mdash;The gauge of a railway, or its width from inside to inside
-of rails, affects both its cost and efficiency. If the gauge be
-exceptionally wide, then the expenditure on works and rolling-stock
-will be proportionately heavy; and although theoretically the extra
-wide gauge may possess greater capabilities for accommodation and
-high-speed travelling, we may find in practice that the necessary
-requirements may be provided on a much more moderate gauge. On the
-other hand, if the gauge be exceptionally narrow, there will be
-diminished convenience both for passengers and merchandise, and a
-corresponding limit to the speed in transit.</p>
-
-<p>In isolated districts, where passenger traffic is of secondary
-importance, and where the principal merchandise will be heavy without
-being bulky, such as mineral ores, slates, etc., a comparative narrow
-gauge may possibly suit the purpose. For main trunk lines, however,
-where a large, heavy, and fast passenger traffic will have to be
-worked, and where goods of all kinds, many of them bulky without being
-heavy, will have to be carried, an ample gauge must be selected to
-ensure convenience and safety. A liberal gauge permits the use of
-commodious rolling-stock without any great amount of lateral
-overhanging weight outside the wheels; whereas with a narrow gauge
-there is the tendency&mdash;if not the necessity&mdash;to use vehicles which
-<!--048.png--><a name="Page_38" id="Page_38"></a><span class="pagenum">[Pg 38]</span>
-have too great a lateral overhang for proper stability, except at very
-moderate speeds.</p>
-
-<p>The following list shows the gauges adopted in various <span style="white-space:nowrap;">countries:&mdash;</span></p>
-
-<table summary="gauges in various countries">
-<tr><td></td><td class="centernobox">ft.</td><td class="centernobox">ins.</td>
-</tr>
-<tr><td class="left">England, Scotland, and Wales</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Ireland</td><td class="centernobox">5</td><td class="centernobox">3</td>
-</tr>
-<tr><td class="left">United States</td><td class="centernobox">4</td><td class="centernobox">8½,</td><td class="left">with some lines 5 ft., 5 ft. 6 ins., and 6 ft.</td>
-</tr>
-<tr><td class="left">Canada</td><td class="centernobox">4</td><td class="centernobox">8½</td><td class="left">and 5 ft. 6 ins.</td>
-</tr>
-<tr><td class="left">France</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Belgium</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Holland</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Germany</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Austria</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Switzerland</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Italy</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Turkey</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Hungary</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Denmark</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Norway</td><td class="centernobox">4</td><td class="centernobox">8½</td><td class="left">and 3 ft. 6 ins.</td>
-</tr>
-<tr><td class="left">Sweden</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Mexico</td><td class="centernobox">4</td><td class="centernobox">8½</td><td class="left">and 3 ft.</td>
-</tr>
-<tr><td class="left">Egypt</td><td class="centernobox">4</td><td class="centernobox">8½</td><td class="left">and 3 ft. 6 ins.</td>
-</tr>
-<tr><td class="left">Peru</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Nova Scotia</td><td class="centernobox">4</td><td class="centernobox">8½</td><td class="left">and 5 ft. 6 ins.</td>
-</tr>
-<tr><td class="left">New South Wales</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Brazil</td><td class="centernobox">4</td><td class="centernobox">8½,</td><td class="left">5 ft. 3 ins., and 5 ft. 6 ins.</td>
-</tr>
-<tr><td class="left">Uruguay Republic</td><td class="centernobox">4</td><td class="centernobox">8½</td>
-</tr>
-<tr><td class="left">Russia</td><td class="centernobox">5</td><td class="centernobox">0</td>
-</tr>
-<tr><td class="left">South Australia</td><td class="centernobox">5</td><td class="centernobox">3</td>
-</tr>
-<tr><td class="left">New Zealand</td><td class="centernobox">3</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">British India</td><td class="centernobox">5</td><td class="centernobox">6</td><td class="left">and 1 metre.</td>
-</tr>
-<tr><td class="left">Ceylon</td><td class="centernobox">5</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Spain</td><td class="centernobox">5</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Portugal</td><td class="centernobox">5</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Chili</td><td class="centernobox">5</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Argentine Republic</td><td class="centernobox">5</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Cape Colonies</td><td class="centernobox">3</td><td class="centernobox">6</td>
-</tr>
-<tr><td class="left">Japan</td><td class="centernobox">3</td><td class="centernobox">6</td>
-</tr>
-</table>
-
-<p>After many years’ experience of actual working, the broad, 7 feet,
-gauge of the Great Western Railway has been abandoned for the 4 feet
-8½ inch gauge. Doubtless this decision was the result of most careful
-deliberation, and was made upon convincing proof that the 4 feet 8½
-inch gauge could fulfil all the advantages claimed for the wider
-gauge, whilst at the same time it possessed the merit of less cost of
-construction and working, and greater facilities for the exchange of
-traffic with other lines having the standard gauge. The facility of
-exchange, or through working of rolling-stock, is a leading element of
-successful railway working, and it is difficult to estimate what would
-be the amount of loss and delay if we had any great extent of break of
-gauge on the main trunk lines of our own country.</p>
-
-<p>Although some countries have selected gauges of 5 feet and
-<!--049.png--><a name="Page_39" id="Page_39"></a><span class="pagenum">[Pg 39]</span>
-5 feet
-6 inches, it is interesting to note that the largest number have
-adopted the English standard gauge of 4 feet 8½ inches, and that the
-miles of line laid to this gauge far outnumber all the others. The
-fact that our own home lines, the principal Continental lines, and
-nearly all that vast network of railways in the United States of
-America, have been laid to the 4 feet 8½ inch gauge, testifies to the
-general opinion of its utility and efficiency; and we know that
-included in that list are the railways which carry the largest,
-heaviest, and fastest train service in the world.</p>
-
-<p>It would be interesting to trace back, and, if possible, ascertain
-from whence the exact gauge of 4 feet 8½ inches was derived. No doubt,
-in the early days of the pioneer iron highways in England, the
-railways were made the same gauge as the tramroads which they
-superseded. But why was 4 feet 8½ inches the gauge of the tramroads?
-We may reasonably infer that the first four-wheeled waggons used on
-the early tramroads were in reality the same waggons which had been
-previously used on the common roads for the conveyance of coal and
-minerals to the ports for shipment, and that the waggons were merely
-transferred from the roughly paved or macadamised roads to the
-tramroads. Flanged wheels were then unknown, and the introduction of
-the tram-plates was at first simply designed to lessen the resistance
-to haulage. The gauge, or width between the wheels, of these waggons
-may have been the outcome of long experience as to the most suitable
-width for convenience of load, stability during transit, or for space
-occupied on the highway. The width may have been handed down from
-generation to generation, going back to the time when wheeled vehicles
-were first built in the country. Perhaps in the beginning the first
-vehicles may have been imported from Italy, or Greece&mdash;countries which
-in the earlier ages were the most advanced in matters of luxury and
-convenience.</p>
-
-<p>When in Pompeii, a few years ago, the writer measured the spaces
-between a large number of the <em>wheel-ruts</em> which are worn deep
-into the paving-stones in many of the principal streets of that
-wonderful unearthed city. These paving-stones, very irregular in
-shape, and many of them 2 feet 6 inches long by 1 foot 6 inches wide,
-are carefully fitted together, and form a compact massive pavement
-from curbstone to curbstone. The wheel-tracks, which are in many
-places worn into the stones
-<!--050.png--><a name="Page_40" id="Page_40"></a><span class="pagenum">[Pg 40]</span>
-to the depth of an inch or an inch and a
-half, are always distinct, and there is no difficulty in defining the
-corresponding track.</p>
-
-<p>The result of a large number of measurements gave an average width of
-about 4 feet 11 inches from centre to centre of the wheel-tracks, a
-curious coincidence with the gauge of our own road vehicles at the
-beginning of the railway era. Whether our selection of the railway
-gauge of 4 feet 8½ inches has been the result of study, imitation, or
-caprice, we certainly have the silent testimony of these old deep-worn
-stones to prove that two thousand years ago the chariots of Pompeii
-were of very similar gauge to our own of modern times.</p>
-
-<p>Narrow-gauge railways, of gauges varying from 1 foot 10½ inches on the
-Festiniog Railway, to 3 feet, 3 feet 3 inches (metre), and 3 feet 6
-inches, have been made in several places both at home and abroad.
-Generally speaking, they have been constructed as subsidiary or
-auxiliary lines in thinly populated districts, with a view to afford
-some railway accommodation where it was considered that lines of the
-standard gauge would not pay. In some instances abroad long lines of
-narrow gauge&mdash;3 feet and 3 feet 6 inches&mdash;have been constructed as
-main trunk lines in newly opened out districts. Some of these have
-since been altered to a wider gauge as the traffic developed, and
-experience proved that the narrow width of the vehicles was unsuitable
-for quick transit, or convenience in the accommodation of passengers
-and goods.</p>
-
-<p>The object in making a line to a narrow gauge is doubtless to save
-cost in the original construction; but when a scheme for an altered
-gauge is put forward, it will be well to consider what amount of
-advantage or saving would be effected by deviating from the standard
-gauge.</p>
-
-<p>If there be almost a certainty that such proposed line will always
-remain isolated from all other existing railways of the standard
-gauge, then perhaps the selection of gauge may be one of minor
-importance, and there remains but the question whether the description
-of traffic, and the weights to be carried, can be worked to any
-greater advantage, or more economically, by deviating from the
-standard gauge.</p>
-
-<p>If, however, there be a fair probability that such proposed line may
-at some future time become part of an already established railway
-system, it would appear to be more prudent to make the line to the
-standard gauge, and effect economies
-<!--051.png--><a name="Page_41" id="Page_41"></a><span class="pagenum">[Pg 41]</span>
-by introducing steeper gradients,
-sharper curves, and lighter permanent way, and keep down working
-expenses by using lighter locomotives, worked at slower speeds.</p>
-
-<p>High speeds are not expected on narrow gauge railways, and no
-complaints are made about passenger trains whose highest running speed
-does not exceed 20 miles per hour. By conceding the same indulgence to
-light railways made to the standard gauge, great economies might be
-introduced both in their construction and working. The similarity of
-gauge would admit the transit of the carriages and waggons of other
-standard gauge lines, and so avoid all cost and delay in <a name="trans"></a>transshipment.
-The heavy engines could be kept for the main-line working, and light
-engines for slow speeds would serve for the light standard-gauge
-lines. As traffic developed, and the train service required heavier
-and faster trains, the light rails could be removed, and replaced by
-those of heavier section to correspond to the main line. The
-similarity of gauge would permit uninterrupted transit of all vehicles
-to a common centre for repairs, whereas the narrow gauge carriages and
-waggons, being limited to running only on their own district, must
-have separate workshops for their repair.</p>
-
-<p>When considering the cost of construction and working of a
-narrow-gauge railway as compared with one of the standard gauge, there
-are certain items which are common to both, and in which the narrow
-gauge could not be expected to obtain any advantage over the standard
-gauge.</p>
-
-<p>There would not be any saving in getting up the scheme in the first
-instance;<br />
-Nor in the Parliamentary expenses;<br />
-Nor in the engineering or carrying out of the works;<br />
-Nor in the station accommodation, waiting-rooms, and offices;<br />
-Nor in the signals and interlocking arrangements;<br />
-Nor in the telegraph;<br />
-Nor in the working staff and train men;<br />
-Nor in the maintenance of the permanent way, as the same number of men
-would be required for the inspection and packing of the road, perhaps
-more.</p>
-
-<p>Little or no saving could be expected in the bridges under the
-railway, as these must be made to the prescribed widths and heights,
-irrespective of the gauge of the railways.</p>
-
-<p>Little, if any, saving could be made in river or stream
-<!--052.png--><a name="Page_42" id="Page_42"></a><span class="pagenum">[Pg 42]</span>
-bridges, as the
-same amount of waterway would have to be provided in each case.</p>
-
-<p>The same remark applies to culverts and drains.</p>
-
-<p>There would, on the other hand, be a small saving in the quantity of
-land to be acquired to the extent of a narrow strip or zone,
-represented by the difference in width between the narrow and standard
-gauges.</p>
-
-<p>There would also be the same small proportionate saving in the
-embankments and cuttings to the extent of the difference in gauge.</p>
-
-<p>Also a saving in the overline bridges and road approaches in
-consequence of less width and height of the opening through those
-bridges.</p>
-
-<p>And a saving in the rails, sleepers, and ballast of the permanent way,
-to the extent consistent with efficiency. That some saving may be
-effected in these is undoubted, but it is necessary to exercise
-caution, and not rush to the opposite extreme by making the parts too
-light. A rail should be made not only strong enough to carry well the
-engines that have to pass over it, but it should also be heavy enough
-to stand the wear of several years. Narrow-gauge engines must be heavy
-in conformity with the loads they have to haul. The same amount of
-power must be exerted to haul a hundred tons on a given gradient,
-whether the gauge be narrow or broad. In some cases of narrow-gauge
-railways the original rails, which weighed only 45 lbs. per yard, have
-since been replaced with others weighing 60 and 65 lbs. per yard. The
-light 45 lb. rails were evidently not found to be sufficiently heavy
-to keep the road to proper line and level. The result of our everyday
-practice seems to prove that there is not only an advantage, but an
-economy, in adopting rails of a heavy section, and experience would
-therefore indicate that even for a narrow-gauge railway it may not be
-expedient to adopt rails weighing less than 65 lbs. per yard.</p>
-
-<p class="p2"><strong>Gradients.</strong>&mdash;There are very few localities where the rails on any
-line of railway can be laid perfectly level or horizontal for more
-than comparatively short distances. By far the greater portion have to
-be laid on inclined planes of varying rates of inclination to suit the
-general formation of the district traversed, and the circumstances of
-the line to be constructed.</p>
-
-<p>The degree, or rate of inclination, of these inclined planes, or
-<!--053.png--><a name="Page_43" id="Page_43"></a><span class="pagenum">[Pg 43]</span>
-gradients, may be expressed in various ways. A very general method is
-to state the number of feet, metres, etc., which can be measured along
-the gradient before an increased rise or fall of one foot or metre,
-etc., is obtained. Thus a gradient of 1 in 200 signifies a rise or
-fall of 1 foot in 200 feet, or 1 metre in 200 metres.</p>
-
-<p>Sometimes the rate of inclination is expressed by stating the number
-of feet of rise or fall in a mile. In this way a gradient would be
-described as falling at the rate of 30 feet in a mile, rising at the
-rate of 20 feet in a mile, etc. Twenty feet to a mile is equal to 1 in
-264.</p>
-
-<p>Another method is to give the percentage of rise or fall. In this way
-the inclination would be expressed as a 1 per cent. gradient, 2 per
-cent. gradient, ½ per cent. gradient, etc., which for comparison would
-signify 1 in 100, 1 in 50, and 1 in 200 respectively.</p>
-
-<p>The gradients of a railway most materially influence its facility and
-cost of working, and every effort should be used to make them as easy
-as possible consistent with the prospect of the line.</p>
-
-<p>Steep gradients signify heavy locomotives, increased cost of
-motive-power, reduced speed, and light loads.</p>
-
-<p>The following tabulated memoranda show the approximate loads,
-exclusive of engine and tender, which can be hauled on the level and
-on certain inclines at various speeds by engines of the quoted
-capacities and steam admissions. A medium-sized, ordinary type of
-passenger and goods engine has been selected for each of the examples.
-The working of the passenger engine and train is assumed to be under
-favourable circumstances, with fine weather, fairly straight line,
-first-class permanent way, modern rolling-stock with oil axle-boxes
-and perfect lubrication, and all the conditions most suitable to
-ensure the least resistance to the moving load. For the goods engine
-and train a greater resistance per ton of load is assumed, as the
-goods trucks are never so perfect or easy in the running as the
-passenger carriages. A certain amount of side wind is taken into
-consideration, and also an allowance for moderately sharp curves, the
-object being to indicate what may be looked upon as fair, average,
-workable loads.</p>
-
-<p>The loads for engines of larger or smaller dimensions, or higher or
-lower pressures, may be obtained by working out the
-<!--054.png--><a name="Page_44" id="Page_44"></a><span class="pagenum">[Pg 44]</span>
-proportion between
-the tractive force put down in any of the columns of the tabulated
-memoranda and the ascertained tractive force of any other engine under
-the same conditions of cut-off and speed.</p>
-
-<div class="nothandheld">
-<table summary="loads for engines, part one" class="smaller">
-
-<tr><td class="leftnobox t b"></td>
-    <td class="lefthnobox t b l" colspan="4"><p class="center"><span class="sc">Passenger Engine.</span></p>
-        <p>Six wheels, driving and trailing wheels coupled, 6 ft. 6 ins. diameter.
-        Cylinders, 17 ft. × 24 ft. Locked-down pressure on safety-valves, 140 lbs. per
-        square inch. Assumed pressure at cylinders, 120 lbs. per square inch.</p>
-        <p>Weight of engine&ensp;39 tons.<br />
-        &emsp; ” &emsp; tender &ensp;<span class="u">24</span> tons.<br />
-        <span class="hide">000000000000 </span>63 tons.</p></td>
-    <td class="lefthnobox t b l" colspan="4"><p class="center"><span class="sc">Goods Engine.</span></p>
-        <p>Six wheels, all coupled, 4 ft. 6 ins. diameter. Cylinders, 17 ft. × 24 ft.
-        Locked-down pressure on safety-valves, 140 lbs. per square inch. Assumed
-        pressure at cylinders, 120 lbs. per square inch.</p>
-        <p>Weight of engine&ensp;34 tons.<br />
-        &emsp; ” &emsp; tender &ensp;<span class="u">24</span> tons.<br />
-        <span class="hide">000000000000 </span>58 tons.</p></td>
-</tr>
-
-<tr><td class="left"><span style="white-space:nowrap;">Assumed cut-off</span></td>
-    <td class="centernobox l">¼</td><td class="centernobox l">⅓</td>
-    <td class="centernobox l">½</td><td class="centernobox l">¾</td>
-    <td class="centernobox l">¼</td><td class="centernobox l">⅓</td>
-    <td class="centernobox l">½</td><td class="centernobox l">¾</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;mean effective pressure, lbs.</td>
-    <td class="rightm l">45</td><td class="rightm l">56</td><td class="rightm l">76</td>
-    <td class="rightm l">100</td>
-    <td class="rightm l">45</td><td class="rightm l">56</td><td class="rightm l">76</td>
-    <td class="rightm l">100</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;tractive force, lbs.</td>
-    <td class="rightm l">4000</td><td class="rightm l">4979</td>
-    <td class="rightm l">6758</td><td class="rightm l">8892</td>
-    <td class="rightm l">5780</td><td class="rightm l">7192</td>
-    <td class="rightm l">9760</td><td class="rightm l">12844</td>
-</tr>
-
-<tr><td class="left">Speed&nbsp;in&nbsp;miles per hour</td>
-    <td class="rightm l">60</td><td class="rightm l">40</td>
-    <td class="rightm l">30</td><td class="rightm l">15</td>
-    <td class="rightm l">40</td><td class="rightm l">30</td>
-    <td class="rightm l">20</td><td class="rightm l">15</td>
-</tr>
-
-<tr class="smaller"><td></td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td>
-</tr>
-
-<tr><td class="left">Level</td><td class="rightm l">97</td>
-    <td class="rightm l">230</td><td class="rightm l">447</td>
-    <td class="rightm l">892</td><td class="rightm l">213</td>
-    <td class="rightm l">358</td><td class="rightm l">623</td>
-    <td class="rightm l">907</td>
-</tr>
-
-<tr><td class="left">1 in 1000</td><td class="rightm l">84</td>
-    <td class="rightm l">196</td><td class="rightm l">373</td>
-    <td class="rightm l">707</td><td class="rightm l">187</td>
-    <td class="rightm l">310</td><td class="rightm l">532</td>
-    <td class="rightm l">768</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 800</td><td class="rightm l">81</td>
-    <td class="rightm l">188</td><td class="rightm l">358</td>
-    <td class="rightm l">671</td>
-    <td class="rightm l">181</td><td class="rightm l">299</td>
-    <td class="rightm l">512</td><td class="rightm l">739</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 600</td><td class="rightm l">76</td>
-    <td class="rightm l">177</td><td class="rightm l">335</td>
-    <td class="rightm l">618</td>
-    <td class="rightm l">172</td><td class="rightm l">285</td>
-    <td class="rightm l">482</td><td class="rightm l">695</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 400</td><td class="rightm l">68</td>
-    <td class="rightm l">157</td><td class="rightm l">296</td>
-    <td class="rightm l">533</td>
-    <td class="rightm l">157</td><td class="rightm l">257</td>
-    <td class="rightm l">432</td><td class="rightm l">621</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 300</td><td class="rightm l">60</td>
-    <td class="rightm l">141</td><td class="rightm l">263</td>
-    <td class="rightm l">467</td>
-    <td class="rightm l">143</td><td class="rightm l">233</td>
-    <td class="rightm l">390</td><td class="rightm l">560</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 250</td><td class="rightm l">55</td>
-    <td class="rightm l">129</td><td class="rightm l">241</td>
-    <td class="rightm l">424</td>
-    <td class="rightm l">133</td><td class="rightm l">216</td>
-    <td class="rightm l">361</td><td class="rightm l">519</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 200</td><td class="rightm l">47</td>
-    <td class="rightm l">114</td><td class="rightm l">213</td>
-    <td class="rightm l">372</td>
-    <td class="rightm l">120</td><td class="rightm l">195</td>
-    <td class="rightm l">324</td><td class="rightm l">467</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 150</td><td class="rightm l">37</td>
-    <td class="rightm l">93</td><td class="rightm l">177</td>
-    <td class="rightm l">304</td>
-    <td class="rightm l">101</td><td class="rightm l">165</td>
-    <td class="rightm l">276</td><td class="rightm l">397</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 100</td><td class="rightm l">21</td>
-    <td class="rightm l">63</td><td class="rightm l">126</td>
-    <td class="rightm l">217</td>
-    <td class="rightm l">74</td><td class="rightm l">123</td>
-    <td class="rightm l">208</td><td class="rightm l">302</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  90</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">56</td><td class="rightm l">114</td>
-    <td class="rightm l">197</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">113</td>
-    <td class="rightm l">191</td><td class="rightm l">279</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  80</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">48</td><td class="rightm l">101</td>
-    <td class="rightm l">175</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">101</td>
-    <td class="rightm l">172</td><td class="rightm l">253</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  75</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">43</td><td class="rightm l">94</td>
-    <td class="rightm l">164</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">95</td>
-    <td class="rightm l">163</td><td class="rightm l">240</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  70</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">39</td><td class="rightm l">86</td>
-    <td class="rightm l">152</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">88</td>
-    <td class="rightm l">153</td><td class="rightm l">226</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  60</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">28</td><td class="rightm l">70</td>
-    <td class="rightm l">128</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">74</td>
-    <td class="rightm l">131</td><td class="rightm l">196</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  50</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">53</td>
-    <td class="rightm l">101</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">107</td><td class="rightm l">163</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  40</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">73</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">127</td>
-</tr>
-
-<tr><td class="left b">&ensp; ” &emsp;  25</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">&mdash;</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">27</td>
-    <td class="rightm l b">&mdash;</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">&mdash;</td><td class="rightm l b">67</td>
-</tr>
-</table>
-</div><!--end full table-->
-
-<div class="handheld chapter">
-<table summary="loads for engines, part one" class="smaller">
-
-<tr><td class="leftnobox t b"></td>
-    <td class="lefthnobox t b l" colspan="4"><p class="center"><span class="sc">Passenger Engine.</span></p>
-        <p>Six wheels, driving and trailing wheels coupled, 6 ft. 6 ins. diameter.
-        Cylinders, 17 ft. × 24 ft. Locked-down pressure on safety-valves, 140 lbs. per
-        square inch. Assumed pressure at cylinders, 120 lbs. per square inch.</p>
-        <p>Weight of engine&ensp;39 tons.<br />
-        &emsp; ” &emsp; tender &ensp;<span class="u">24</span> tons.<br />
-        <span class="hide">0000000000000 </span>63 tons.</p></td>
-</tr>
-<tr><td class="nonshrink"><span style="white-space:nowrap;">Assumed cut-off</span></td>
-    <td class="maxwide centernobox l">¼</td><td class="maxwide centernobox l">⅓</td>
-    <td class="maxwide centernobox l">½</td><td class="maxwide centernobox l">¾</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;mean effective pressure, lbs.</td>
-    <td class="rightm l">45</td><td class="rightm l">56</td><td class="rightm l">76</td>
-    <td class="rightm l">100</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;tractive force, lbs.</td>
-    <td class="rightm l">4000</td><td class="rightm l">4979</td>
-    <td class="rightm l">6758</td><td class="rightm l">8892</td>
-</tr>
-
-<tr><td class="left">Speed&nbsp;in&nbsp;miles per hour</td>
-    <td class="rightm l">60</td><td class="rightm l">40</td>
-    <td class="rightm l">30</td><td class="rightm l">15</td>
-</tr>
-
-<tr class="smaller"><td></td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td><td class="rightm l">Tons.</td>
-    <td class="rightm l">Tons.</td>
-</tr>
-
-<tr><td class="left">Level</td><td class="rightm l">97</td>
-    <td class="rightm l">230</td><td class="rightm l">447</td>
-    <td class="rightm l">892</td>
-</tr>
-
-<tr><td class="left">1 in 1000</td><td class="rightm l">84</td>
-    <td class="rightm l">196</td><td class="rightm l">373</td>
-    <td class="rightm l">707</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 800</td><td class="rightm l">81</td>
-    <td class="rightm l">188</td><td class="rightm l">358</td>
-    <td class="rightm l">671</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 600</td><td class="rightm l">76</td>
-    <td class="rightm l">177</td><td class="rightm l">335</td>
-    <td class="rightm l">618</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 400</td><td class="rightm l">68</td>
-    <td class="rightm l">157</td><td class="rightm l">296</td>
-    <td class="rightm l">533</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 300</td><td class="rightm l">60</td>
-    <td class="rightm l">141</td><td class="rightm l">263</td>
-    <td class="rightm l">467</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 250</td><td class="rightm l">55</td>
-    <td class="rightm l">129</td><td class="rightm l">241</td>
-    <td class="rightm l">424</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 200</td><td class="rightm l">47</td>
-    <td class="rightm l">114</td><td class="rightm l">213</td>
-    <td class="rightm l">372</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 150</td><td class="rightm l">37</td>
-    <td class="rightm l">93</td><td class="rightm l">177</td>
-    <td class="rightm l">304</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 100</td><td class="rightm l">21</td>
-    <td class="rightm l">63</td><td class="rightm l">126</td>
-    <td class="rightm l">217</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  90</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">56</td><td class="rightm l">114</td>
-    <td class="rightm l">197</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  80</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">48</td><td class="rightm l">101</td>
-    <td class="rightm l">175</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  75</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">43</td><td class="rightm l">94</td>
-    <td class="rightm l">164</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  70</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">39</td><td class="rightm l">86</td>
-    <td class="rightm l">152</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  60</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">28</td><td class="rightm l">70</td>
-    <td class="rightm l">128</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  50</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">53</td>
-    <td class="rightm l">101</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  40</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">73</td>
-</tr>
-
-<tr><td class="left b">&ensp; ” &emsp;  25</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">&mdash;</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">27</td>
-</tr>
-</table>
-</div>
-
-<div class="chapter handheld">
-<table summary="loads for engines, part two" class="smaller">
-
-<tr><td class="leftnobox t b"></td>
-    <td class="lefthnobox t b l" colspan="4"><p class="center"><span class="sc">Goods Engine.</span></p>
-        <p>Six wheels, all coupled, 4 ft. 6 ins. diameter. Cylinders, 17 ft. × 24 ft.
-        Locked-down pressure on safety-valves, 140 lbs. per square inch. Assumed
-        pressure at cylinders, 120 lbs. per square inch.</p>
-        <p>Weight of engine&ensp;34 tons.<br />
-        &emsp; ” &emsp; tender &ensp;<span class="u">24</span> tons.<br />
-        <span class="hide">0000000000000 </span>58 tons.</p></td>
-</tr>
-<tr><td class="nonshrink"><span style="white-space:nowrap;">Assumed cut-off</span></td>
-    <td class="maxwide centernobox l">¼</td><td class="maxwide centernobox l">⅓</td>
-    <td class="maxwide centernobox l">½</td><td class="maxwide centernobox l">¾</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;mean effective pressure, lbs.</td>
-    <td class="rightm l">45</td><td class="rightm l">56</td><td class="rightm l">76</td><td class="rightm l">100</td>
-</tr>
-
-<tr><td class="left">&emsp;”&emsp;tractive force, lbs.</td>
-    <td class="rightm l">5780</td><td class="rightm l">7192</td><td class="rightm l">9760</td><td class="rightm l">12844</td>
-</tr>
-
-<tr><td class="left">Speed&nbsp;in&nbsp;miles per hour</td>
-    <td class="rightm l">40</td><td class="rightm l">30</td>
-    <td class="rightm l">20</td><td class="rightm l">15</td>
-</tr>
-
-<tr class="smaller"><td></td><td class="rightm l">Tons.</td><td class="rightm l">Tons.</td><td class="rightm l">Tons.</td><td class="rightm l">Tons.</td>
-</tr>
-
-<tr><td class="left">Level</td>
-    <td class="rightm l">213</td><td class="rightm l">358</td><td class="rightm l">623</td>
-    <td class="rightm l">907</td>
-</tr>
-
-<tr><td class="left">1 in 1000</td>
-    <td class="rightm l">187</td><td class="rightm l">310</td><td class="rightm l">532</td>
-    <td class="rightm l">768</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 800</td>
-    <td class="rightm l">181</td><td class="rightm l">299</td><td class="rightm l">512</td>
-    <td class="rightm l">739</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 600</td>
-    <td class="rightm l">172</td><td class="rightm l">285</td><td class="rightm l">482</td>
-    <td class="rightm l">695</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 400</td>
-    <td class="rightm l">157</td><td class="rightm l">257</td><td class="rightm l">432</td>
-    <td class="rightm l">621</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 300</td>
-    <td class="rightm l">143</td><td class="rightm l">233</td><td class="rightm l">390</td>
-    <td class="rightm l">560</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 250</td>
-    <td class="rightm l">133</td><td class="rightm l">216</td><td class="rightm l">361</td>
-    <td class="rightm l">519</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 200</td>
-    <td class="rightm l">120</td><td class="rightm l">195</td><td class="rightm l">324</td>
-    <td class="rightm l">467</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 150</td>
-    <td class="rightm l">101</td><td class="rightm l">165</td><td class="rightm l">276</td>
-    <td class="rightm l">397</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &ensp; 100</td>
-    <td class="rightm l">74</td><td class="rightm l">123</td><td class="rightm l">208</td>
-    <td class="rightm l">302</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  90</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">113</td><td class="rightm l">191</td>
-    <td class="rightm l">279</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  80</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">101</td><td class="rightm l">172</td>
-    <td class="rightm l">253</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  75</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">95</td><td class="rightm l">163</td>
-    <td class="rightm l">240</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  70</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">88</td><td class="rightm l">153</td>
-    <td class="rightm l">226</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  60</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">74</td><td class="rightm l">131</td>
-    <td class="rightm l">196</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  50</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td><td class="rightm l">107</td>
-    <td class="rightm l">163</td>
-</tr>
-
-<tr><td class="left">&ensp; ” &emsp;  40</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">&mdash;</td>
-    <td class="rightm l">&mdash;</td><td class="rightm l">127</td>
-</tr>
-
-<tr><td class="left b">&ensp; ” &emsp;  25</td>
-    <td class="rightm l b">&mdash;</td><td class="rightm l b">&mdash;</td><td class="rightm l b">&mdash;</td>
-    <td class="rightm l b">67</td>
-</tr>
-</table>
-</div>
-
-<p class="center smaller"><span class="sc">Note.</span>&mdash;The column loads in tons are exclusive of the weight of
-engine and tender.</p>
-
-<p><!--055.png--><a name="Page_45" id="Page_45"></a><span class="pagenum">[Pg 45]</span>
-From the above memoranda it will be seen how greatly the gradients
-affect the loads. For an important main trunk line, with a heavy and
-frequent train-service of passengers and goods, the introduction of
-steep gradients would not only reduce the speed of the train-working,
-but would probably involve the necessity of assistant engines over
-those parts of the line; and it may be prudent, where possible, to
-incur heavier earthworks, or considerable detours, or tunnels, to
-obtain more favourable gradients. For such a line the additional cost,
-and the extra distance caused by a detour of a mile or more, will be
-of far less importance than the interruption in the train service
-arising from a serious reduction in speed or taking on assistant
-engines. On many railways abroad there are very interesting examples
-of long detours of several miles, carefully studied out to obtain
-greater length and easier gradients, resulting in the construction of
-lines over which the traffic can be worked without necessitating
-auxiliary engine-power. On the other hand, there are situations where
-steep gradients cannot be avoided, where certain altitudes must be
-reached, and where there is no alternative but to face the inevitable.</p>
-
-<p>On secondary lines, and short branch lines, where the traffic is not
-expected to be heavy, and where speed is not so important, it may be
-policy to economize outlay and introduce <a name="steeper"></a>steeper
-gradients than on the main line.</p>
-
-<p>Half a mile of a rather steep gradient is not felt so much when it is
-situate midway between two stations, because the attained speed of the
-train assists the engine over the short distance to the summit; but
-when it occurs as a rising gradient out of a station, it forms a great
-check to the working, particularly in bad or wet weather, when there
-is the risk of the engine slipping, and the entire train sliding back
-into the station.</p>
-
-<p>Long steep gradients not only necessitate increased motive-power for
-the ascending trains, but also require increased brake-power, and
-precautionary measures for the descending trains. Where passenger
-trains are fitted with continuous brakes, the risk of losing control
-is minimized; but with goods trains composed of waggons, having only
-the ordinary independent side-lever brake, it will be found absolutely
-necessary in many cases to have additional heavy brake-vans for
-descending the inclines, and these special vans, unfortunately, will
-form so much extra non-paying weight to be hauled up on the ascending
-trains. Of
-<!--056.png--><a name="Page_46" id="Page_46"></a><span class="pagenum">[Pg 46]</span>
-course, it is quite possible&mdash;and, indeed, in many places
-it is customary&mdash;to pin down some of the side-lever brakes before
-commencing the descent, but once pinned down the brakes cannot be
-eased or taken off until the entire train is brought to a stand.</p>
-
-<p>Every goods waggon should be fitted with a brake, and it would be of
-immense value if that brake could in all cases be applied and
-controlled when the train is in motion.</p>
-
-<p>The American type of long goods waggon, with a four-wheel bogie-truck
-at each end, is fitted with a brake very similar to those adopted on
-the ordinary horse tram-cars. On the top of the waggon a horizontal
-iron hand-wheel, about 18 inches in diameter, is fixed on to a strong
-vertical iron rod, which works in brackets, and extends down below the
-underside of waggon framing. One end of a short length of chain is
-secured to the foot of the vertical rod, and the other end is
-connected by light iron rods to the series of levers which pull on the
-brake-blocks. By rotating the horizontal hand-wheel the chain is
-coiled round the lower end of the vertical rod, the brake-levers are
-pulled over, and brake-pressure applied to the wheels of the waggon.
-The brakesman is supplied with a convenient seat and footboard, and on
-the floor-level of the latter there is a pawl and ratchet attached to
-the vertical rod, which permits the brakes to be applied to the extent
-required. The pawl retains the brakes in position until the brakesman
-with his foot pushes the pawl out of the notch of the rachet and
-releases the brake gearing, which is at once pulled off quite clear by
-strong bow-strings attached to the framework of the bogies.</p>
-
-<p>This type of hand-brake is, perhaps, the simplest that can be made.
-The brakesman has merely to put it on, the pawl and ratchet keep it
-on, and the bow springs take it off when no longer required. Each one
-of these long, loaded goods waggons becomes a very serviceable
-brake-van, and for ascending and descending steep inclines all that is
-necessary is to take on a few additional brakesmen to manage the
-brakes of as many suitable waggons. These incline brakesmen, after
-going down, can return to the summit by the next ascending train,
-their small weight being a mere nothing as compared with that of
-special or extra brake-vans.</p>
-
-<p>On some European lines it is the custom to sprag some of the goods
-waggon wheels when going down exceptionally steep
-<!--057.png--><a name="Page_47" id="Page_47"></a><span class="pagenum">[Pg 47]</span>
-inclines, as well as
-applying the brakes on the ordinary and extra brake-vans. The sprag is
-a piece of wood, circular in section, about 2 feet 6 inches long, and
-5 to 6 inches thick in the middle, tapering off to about 2 inches
-thick at the ends. When the waggon-wheel is just beginning to move,
-the sprag is inserted between the spokes, and being caught against the
-waggon framework, the wheel is held fast, and being unable to revolve,
-remains fixed, and acts like a skid upon the rails. The skidding of
-the wheels upon the rails wears flat places on the wheel tyres, and it
-is needless to mention that the practice is only resorted to in very
-extreme cases. Although a very primitive means for checking the speed
-of a descending train, or for maintaining vehicles stationary on an
-incline, there have been many instances where lives have been saved
-and accidents prevented by the prompt use of a few sprags. Solid or
-close wheels cannot be spragged, only wheels which have spokes or
-openings, and for this reason alone it would be very desirable that in
-every passenger and goods train there should be some spoke or open
-wheels which could be spragged as a last resource, in the event of a
-sudden emergency of brakes failing or train becoming divided on an
-incline.</p>
-
-<p>On ascending gradients there is always the risk of a coupling
-breaking, and the train becoming divided. If the detached portion left
-behind be provided with ample brake-power, hand-brakes, or otherwise,
-no harm may take place beyond a little delay; but if the brake-power
-be insufficient or defective, and if all the wheels are solid wheels
-incapable of admitting a few timely sprags, then the vehicles cannot
-be held, but must slide back, and running unchecked would soon attain
-such a velocity as would cause them either to leave the rails or dash
-into another train standing at the last station. Many lamentable
-accidents have taken place arising from portions of trains breaking
-away and running back, and the sad experience of those casualties
-should call forth every effort to avert a recurrence in the future. It
-may not always be possible to detect a hidden flaw in a coupling, or a
-defect in the brake-gearing until the actual failure occurs; but it is
-quite possible to guard against disastrous results from such failure,
-by providing means to hold the vehicles, and prevent them sliding
-back.</p>
-
-<p>For some years the writer had the entire charge of an important
-railway abroad on which the gradients were very
-<!--058.png--><a name="Page_48" id="Page_48"></a><span class="pagenum">[Pg 48]</span>
-exceptional, and where
-it was absolutely necessary that he should organize the most complete
-precautions to prevent the possibility of trains, or portions of
-trains, running back down inclines. Starting from sea-level, the line,
-which was laid to the 4 feet 8½ inch <a name="gauge1"></a>gauge, rose to a summit of over
-8000 feet, and on the mountain division there were many long gradients
-of 1 in 40, 1 in 33, and in one place a continuous gradient of 1 in 25
-for 12 miles. The specially powerful engines reserved for these heavy
-inclines were each supplied with an ordinary hand-brake, a
-steam-brake, and a Westinghouse continuous brake. The passenger
-carriages, which were of considerable length, and carried on a
-four-wheeled bogie-truck at each end, were all fitted up with the
-Westinghouse brake, and in addition each carriage had its own
-hand-wheel brake with the pawl and ratchet gearing. All the goods
-waggons, which were of the American type, were fitted with hand-wheel
-brakes similar to those on the carriages. Special gangs of trained
-brakesmen took charge of the trains on these inclines, a brakesman to
-every carriage or waggon, and were always in readiness in case of the
-breakage of a coupling, or the failure in the Westinghouse brake or
-brakes on engine. The immunity from accidents justified the combined
-precautions adopted, and proved the possibility of working such severe
-gradients with perfect safety.</p>
-
-<p>The long-continued application of the brakes on heavy inclines
-naturally leads to the question as to the description of wheel to be
-adopted for the work. Not only are the wheels subjected to very severe
-torsional strains, but the temperature at the circumference is raised
-very high in consequence of the friction. Perhaps, theoretically, the
-safest wheel would be one made out of a solid piece of metal, similar
-to the chilled cast-iron wheels of the United States, or the steel
-disc wheels used on some lines in Europe, in either of which holes can
-be left for sprags. Wheels of this description can withstand very
-heavy wear and tear, they are not affected by increased temperature,
-and they certainly have the minimum of parts to work loose. Of the
-built-up wheels, the strong forged-iron-spoke wheel with steel tyres
-shows excellent results, and always gives due warning of loosening by
-indications at the tyre rivets. The suddenness with which the solid
-wooden centre wheels sometimes break up and fall to pieces does not
-commend them for a service where there must be a long-sustained
-application of the brakes. The
-<!--059.png--><a name="Page_49" id="Page_49"></a><span class="pagenum">[Pg 49]</span>
-increased temperature which expands the
-tyre, contracts the wood, and must loosen and weaken the entire wheel.</p>
-
-<p>On all steep gradients the road-bed should be of the most substantial
-character, and the permanent way of a strong description, and
-maintained in perfect order, as the engines for working the traffic
-must necessarily be of a heavy type. The rails will be severely tested
-by the pounding and slipping of the engines on the ascending journey,
-and by the action of the brakes on the descending journey.</p>
-
-<p>In the early days of the railway system, rope-haulage was adopted on
-some of the main lines for working the trains on steep inclines near
-the principal terminal stations. A powerful stationary engine, located
-at the highest point, was employed to work an endless rope which
-passed round large drums at the top and bottom of the incline, and was
-supported on sheaves or pulleys fixed between the rails. The
-connection between the carriages and endless rope was effected by
-means of a short piece of rope called the <em>messenger</em>, which was
-coiled round the main rope in such a manner as to be readily detached
-when the train reached the summit. There are many persons who will
-remember the time when the passenger trains were hauled by an endless
-rope up the 1 in 66 incline from Euston to Camden Town, a distance of
-about a mile and a half, and up the 1 in 48 incline from Lime Street,
-Liverpool, to Edge Hill, a distance of about a mile and a quarter, and
-several others. The rapid strides made in locomotive construction, and
-the increased pressure used in the boilers, enabled much more powerful
-engines to be built, until one by one the rope-haulage machinery has
-disappeared from nearly all the inclines where for years it had been
-considered indispensable. Rope-haulage on inclines is now very rarely
-met with, except at collieries and ironworks, where occasionally the
-rope may be seen so arranged that the loaded waggons descending pull
-up the empty waggons on the opposite or parallel line.</p>
-
-<p class="p2"><strong>Curves.</strong>&mdash;The degree of curvature of a railway curve is generally
-expressed by giving the radius in feet, chains, metres, or other
-national standard measure.</p>
-
-<p>When laying out a line of railway, the natural features of the country
-will necessitate the introduction of curves, and the question for
-consideration will be whether they are to be made of small or large
-radius. In some cases sharp curves are
-<!--060.png--><a name="Page_50" id="Page_50"></a><span class="pagenum">[Pg 50]</span>
-inevitable, except by incurring
-enormous works which would not appear to offer any corresponding
-prospective recompense. In others the curves may be made of easy
-radius, at a comparative moderate extra outlay, if the character of
-the line and description of traffic to be accommodated will warrant
-the expenditure. For main through lines, with heavy, high-speed
-traffic, it is advisable to have the curves of large radius, so as to
-avoid the necessity of reducing speed when passing round them.
-Although a high-class fast train may be allowed to run round an 80
-chain (5280 feet) curve at almost unrestricted speed, safety demands
-that there should be a reduction of speed on curves of 40 or 30 chains
-radius, and a very much greater reduction for curves of 20 chains
-radius and under. A sharp curve will in some places form a greater
-check to fast trains than a length of moderately steep gradient on a
-straight line. In the former the trains running in either direction
-must slow down for some distance before reaching the curve, round
-which they should pass at greatly reduced speed, and then some
-distance must be run before they can attain their full speed again. On
-the other hand, with a rising gradient, on a fairly straight line, the
-acquired momentum of the train will materially assist in ascending the
-incline, and although the speed may be slackened as the train
-advances, there may not be any very great diminution in the running
-before the gradient is passed, and average level line reached again. A
-reduced rate of running must be maintained round curves of small
-radius, for, however substantial the works and permanent way, and
-however well devised and constructed the rolling-stock, there is an
-element of danger ever present when passing round sharp curves at
-anything more than moderate speed. In the great rush for fast through
-trains this point is very apt to be overlooked, and too little time
-allowed for the running. Even with the fastest trains on any line
-there are some portions of the route which must be traversed with
-greater caution and less speed than others, either on account of sharp
-curves or of gradients; and if those who are entrusted with the
-preparations of the time tables do not possess the technical
-information necessary to deal properly with the question of relative
-speeds, there is the strong probability that the programme prepared
-may be one both difficult and dangerous to fulfil. The spirit of
-rivalry is a strong incentive to fast running, but prudence and common
-sense should indicate that
-<!--061.png--><a name="Page_51" id="Page_51"></a><span class="pagenum">[Pg 51]</span>
-record speeds should only be attempted on
-the straight or favourable portions of the line. There is,
-unfortunately, the growing tendency to run faster and faster round the
-curved portion of our lines, heedless of the close approach to the
-limit of safety, and unless this excessive speed be controlled in
-time, the result must be disaster on a very large scale.</p>
-
-<p>A sharp curve leading into or out of a terminal station or main-line
-stopping-station does not so much affect the train running as a sharp
-curve at an intermediate point between stations where the train may be
-expected to run at its maximum speed. Wherever it is possible it is
-very desirable to avoid sharp curves on inclines, because there are
-times when descending trains may acquire a considerable velocity, and
-wheels tightly gripped by the brakes have not the same facility for
-following the curves as when they are running free.</p>
-
-<p>In rugged and mountainous districts sharp curves are almost
-unavoidable, except by introducing a series of tunnels; but in these
-districts both the gradients and curves are alike exceptional, the
-speed is necessarily slow, and special precautions are taken for the
-ascending and descending trains.</p>
-
-<div class="figcenter">
- <a name="fig30"></a>
- <img src="images/i052.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 30 through 38 "
- title="Figures 30 through 38"
- />
-</div>
-
-<p>When setting out reverse curves on a main line a piece of straight
-line should always be laid in between the termination of the one curve
-and the beginning of the other, to allow of a proper adjustment of the
-rails to suit the super-elevation adopted on each of the adjoining
-curves. In station yards and sidings this is not so absolutely
-necessary, the sorting of the carriages and waggons and the
-marshalling of the trains being carried on at a low speed, which does
-not necessitate any super-elevation of the rails on the curves. The
-speed of the train regulates the amount of super-elevation to be given
-on any particular curve, and to ensure smooth and safe running this
-amount must be maintained uniform all round the curve. On curves of
-small radius, guard, or check, rails are frequently placed alongside
-the inner rail, as in <a href="#fig30">Figs. 30 to 33</a>, to check the tendency of the
-engine to leave the rails and run in a straight line. For the
-bull-head road a special chair is used, which holds both the
-running-rail and the check-rail, as shown on the sketch, the rails
-being kept the proper distance apart by the web portion in the centre,
-which forms part of the casting. For the flange railroad, check-rails
-are sometimes made of strong angle irons placed against the flange of
-the running-rail, and bolted to the transverse
-<!--062.png--><!--063.png--><a name="Page_53" id="Page_53"></a><span class="pagenum">[Pg 53]</span>
-sleepers. This method
-is not nearly so strong or efficient as the arrangement shown on <a href="#fig30">Fig.
-33</a>, with a cast-iron distance-block about six inches long, placed
-between the running-rail and check-rail, and all tied together with a
-strong through bolt. A bolt-hole is punched in the edge of the flange
-of check-rail, and a crab bolt and clip holds the two rails on the
-sleeper. The cast-iron distance-blocks are placed just outside the
-sleeper, so as not to interfere with the holding-down bolt. Doubtless
-these guard rails do good service, but if the leading wheels of the
-engine have sharp or worn flanges there is the possibility that the
-wheel, pressing against the high rail, may mount the rail, and throw
-the train off the line. A more secure method is to place the guard
-outside the high rail, as in <a href="#fig30">Figs. 34 to 38</a>. This can be done by
-securing a strong continuous longitudinal timber to the
-cross-sleepers&mdash;or to the cross-girders in the case of a girder
-bridge&mdash;with its outer or striking edge protected with a fairly heavy
-angle iron. The top of this outside guard above the rail level may be
-three inches or more, according to the height of any hanging spring,
-or portion of brake apparatus belonging to the rolling-stock. The
-distance between the striking-face of the guard and the inside of head
-of rail should be about 5 inches, or such width that before the flange
-of the wheel can mount on the top of the rail, the face of the
-wheel-tyre will be brought into contact with the striking-face of the
-outside guard, and thus effectually prevent the wheel leaving the
-rail. The sketches show some of the types applicable to the chair
-road, and to the flange railroad. In <a href="#fig30">Figs. 34, 35, and 37</a>, the outside
-brackets are of heavy angle iron cut off in lengths to correspond to
-the width of the sleeper. In <a href="#fig30">Fig. 36</a> the cast-iron chair is
-lengthened, and has an end bracket to support the guard timber. In
-<a href="#fig30">Fig. 37</a> a hard wood bolster is fastened on the top of each sleeper,
-and on this is placed the continuous guard timber. This method of
-increased security is frequently adopted on girder bridges and long
-iron viaducts which are on the straight, and in such cases it is usual
-to place the guards outside each of the rails forming the track.</p>
-
-<p>The introduction of bogie engines and bogie carriages has conduced
-largely to the safe working of the train-service over the curved
-portions of many of our home railways, as well as to the economy in
-the wear and tear of permanent way and rolling-stock. The action of
-long rigid wheel-base vehicles passing
-<!--064.png--><a name="Page_54" id="Page_54"></a><span class="pagenum">[Pg 54]</span>
-round sharp curves is
-detrimental to all the parts brought into contact. Not only is there
-the constant tendency to mount the rails, and spread the gauge, but
-the tiny shreds of steel scattered all along close to the
-rail&mdash;particles ground off the rails, or off the wheel-tyres, or
-both&mdash;testify to useless wear, unnecessary friction, and great waste
-of motive-power.</p>
-
-<p>The gradual increase of accommodation and conveniences in the carriage
-stock of European railways led to the gradual increase in the length
-of the vehicles. The six-wheeled carriage superseded the four-wheeled
-carriage, on account of its increased steadiness when running, but the
-introduction of long sleeping-cars, dining-cars, and corridor cars
-necessitated some better wheel arrangement than the ordinary six-wheel
-type could supply. The six wheels had been spread as far apart as was
-admissible for carrying weight and passing round curves, and something
-had to be done to meet the demand for still longer carriages. Many of
-the six-wheeled carriages at present running on our own home lines
-have a fixed wheel-base as long as 22 feet, and with this length the
-horn-plates must undergo a very considerable strain when adapting
-themselves for the passage round curves of small radius. On a curve of
-15 chains radius (990 feet) a chord of 22 feet will have a versed sine
-or offset of 0·73 of an inch, and on a curve of 10 chains radius (660
-feet) an offset of 1·10 of an inch. Fortunately, curves of the above
-small radius are not very numerous on our main lines; but wherever
-they do occur, the conflict between the long fixed wheel-base
-rolling-stock and the permanent way must be very severe to both.
-Several descriptions of eight-wheeled carriages have been tried on our
-home lines; but the system which is now most in favour is the ordinary
-bogie truck, which has been in use for so many years on all American
-railways. A bogie truck is really a short carriage frame complete in
-itself, with its wheels, springs, and brake appliances, and is
-attached to the under side of the carriage body by a central pivot,
-round which the truck can swivel or rotate sufficiently to adapt
-itself to the curved portions of the line. With a bogie truck at each
-end of a long carriage, the vehicle will pass as easily round curves
-as on the straight line, side pressure, or grinding against the rails,
-is obviated, and friction is reduced to a minimum. The bogie truck may
-consist of four wheels or six wheels, according to the length and
-weight of the carriage to be supported.</p>
-
-<div class="figcenter"><!--065.png--><a name="Page_55" id="Page_55"></a><span class="pagenum">[Pg 55]</span>
- <a name="fig39"></a>
- <img src="images/i055.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure Figures 39 through 42"
- title="Figures 39 through 42"
- />
-</div>
-
-<p><!--066.png--><a name="Page_56" id="Page_56"></a><span class="pagenum">[Pg 56]</span>
-<a href="#fig39">Figs. 39, 40, and 41</a> show sketch elevation, plan, and transverse
-section of one pattern of four-wheel bogie truck largely adopted in
-American carriage stock, and although there are other types varying in
-detail, the general principle remains the same in all. The diagram
-sketch (<a href="#fig39">Fig. 42</a>) represents the two bogie trucks slightly swivelled to
-adapt themselves to the curve round which the carriage is supposed to
-be passing.</p>
-
-<p>For carriage or waggon stock with an independent bogie truck at each
-end, the central pivot and swivelling motion supply all the freedom
-that is requisite; but for locomotives it is necessary to provide for
-lateral as well as for swivelling movement. The driving and trailing
-wheels&mdash;and sometimes one or two other pairs of wheels&mdash;work rigidly
-in the frames, and as the normal position of the centre of the bogie
-truck must be in the centre line of the engine for the straight line,
-it is evident that some appliance must be introduced to allow the
-truck to move laterally when the engine has to traverse the curves.</p>
-
-<p><a href="#fig43">Figs. 43, 44, and 45</a> give sketch elevation, plan, and transverse
-section of a swing-link bogie truck as applied to an ordinary American
-locomotive. Its recommendations are its simplicity, its efficiency,
-and its accessibility for inspection and lubrication. The swing-links,
-which provide for the lateral movement, are direct acting, and do not
-require any side springs of steel or indiarubber. All the principal
-parts of the bogie are visible and not mysteriously cased in with
-plate-iron boxwork.</p>
-
-<p>In the sketches several minor details are purposely omitted and only
-sufficient particulars shown to explain the method of working. The
-under side of the upper centre plate which carries the cylinder
-castings and smoke-box end of boiler is cup-shaped, and fits into an
-annular groove or channel in the lower centre plate, which is
-suspended from the framework of the truck by the four swinging links.
-Practically the entire carrying and swivelling work of the bogie truck
-is effected by the annular-groove casting moving round the cup-shaped
-casting, and the centre pin is merely passed down through each to
-guard against the risk of the one lifting out of the other from sudden
-shock or derailment.</p>
-
-<div class="figcenter">
- <a name="fig43"></a>
- <img src="images/i057.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 43 through 46"
- title="Figures 43 through 46"
- />
-</div>
-
-<p>The lateral movement of the truck is obtained by means of the four
-swing-links. When the engine is on the straight road the centre line
-of the bogie is on the centre line of the engine, and the links hang
-in the positions shown on the sketch, inclined
-<!--067.png--><!--068.png--><a name="Page_58" id="Page_58"></a><span class="pagenum">[Pg 58]</span>
-towards the centre; but
-upon entering a curve they come into play, and allow the truck to move
-out sideways to the right or left, according to the direction of the
-curve, the one pair of links assuming a flatter angle, while the other
-pair approach nearer to the vertical, the extent of side movement
-depending on the amount of the curvature. When the engine enters the
-straight line again, the bogie truck resumes its central position.</p>
-
-<p>The Bissell truck consists of one pair of wheels connected to a
-triangular framework, as shown in <a href="#fig43">Fig. 46</a>. The axle-boxes are attached
-to the side of the triangle which lies parallel to the axle, the other
-two sides terminate in a circular ring which works round a centre pin
-fixed to the engine. These two sides are practically the radii of a
-given circle, and permit a large amount of lateral movement, which can
-be controlled by placing suitable stop-pieces to limit the side play
-to the extent desired.</p>
-
-<p>Radial axle-boxes have been tried on the engines of some railways. In
-the best types the opposite boxes are braced together by a diaphragm,
-or plate-iron framework, to ensure that both boxes work together. The
-curved faces of the horn-blocks, in which the radial axle-boxes slide,
-are struck from a centre taken at some point to the rear of the normal
-centre line of the axle, and stops are placed at proper distances to
-control the extent of lateral movement. Although the advocates of
-radial axle-boxes may urge some points in their favour, there are few
-engineers, if any, amongst those who have had practical experience of
-both systems, who would for a moment claim for the radial axle-box
-anything but a modicum of the many advantages obtained by the
-four-wheeled bogie truck.</p>
-
-<p>As one of the principal functions of a four-wheeled bogie truck for an
-engine is to act as a path-finder, or guide, to the other wheels which
-constitute the fixed or rigid wheel-base portion of the machine, it
-follows, therefore, that the full benefit of the bogie truck can only
-be obtained when it is placed at the leading, or front, end of the
-engine. In this position the bogie, with its swivelling arrangement
-and smaller weights, is the first to pass over the rails, and in doing
-so shapes the course and prepares the way for the easy running of the
-heavier wheel weights which have to follow. When the bogie truck is
-placed at the rear end of the engine, its action is restricted to
-affording lateral movement only, and the driving and coupled wheels
-have to force or pound themselves round the curves in a jerky,
-<!--069.png--><a name="Page_59" id="Page_59"></a><span class="pagenum">[Pg 59]</span>
-irregular manner, as compared to their smooth running when following
-the leading or guiding influence of a bogie truck in front.</p>
-
-<p>The wheel-base of a four-wheeled bogie truck for an engine should
-always be greater than the gauge of the line over which the bogie has
-to travel On the 4 feet 8½ inch gauge some of the best results have
-been obtained with bogies having wheel-bases varying from 6 feet to 7
-feet. Where the wheel-centres have been less than 6 feet, the running
-has been found to be much less steady than with the wider spacing; and
-where the wheel-base is not more than the gauge, there is a tendency
-for the bogie to catch, or lock, when passing round sharp curves.</p>
-
-<div class="smaller indent"><!--searchable text of estimate form-->
-<p class="p2"><a href="#back">back to form</a> [Transcriber's Note: Searchable text of form]</p>
-<p class="mt1"><a name="estimateform"></a><span class="sc">Estimate of the Proposed (Railway)</span>.</p>
-<p class="mt1">Line No. </p>
-<p class="mt1">Length of Line:</p>
-<p class="mt1">Miles. F. Chs.</p>
-<p class="mt1">Whether single or double.</p>
-<p class="mt1">Cubic yards. Price per yard.</p>
-<p class="mt1">Earthworks:</p>
-<p class="mt1">Cuttings&mdash;Rock Soft soil Roads Total</p>
-<p class="mt1">Embankments, including roads, __ cubic yards</p>
-<p class="mt1">Bridges, public roads&mdash;number</p>
-<p class="mt1">Accommodation bridges and works</p>
-<p class="mt1">Viaducts</p>
-<p class="mt1">Culverts and drains</p>
-<p class="mt1">Metallings of roads and level crossings</p>
-<p class="mt1">Gatekeepers’ houses at level crossings</p>
-<p class="mt1">Permanent way, including fencing:</p>
-<p class="mt1">Miles. F. Chs. at</p>
-<p class="mt1">Cost per mile.</p>
-<p class="mt1">Permanent way for sidings, and cost of junctions</p>
-<p class="mt1">Stations</p>
-<p class="mt1">Contingencies __ per cent.</p>
-<p class="mt1">Land and buildings</p>
-<p class="mt1">Total £</p>
-<p class="mt1">Dated this &emsp; day of &emsp; 18__</p>
-<p class="mt1">Witness:</p>
-<p class="mt1">Engineer.</p>
-</div><!--end searchable text-->
-</div><!--end chapter one-->
-
-<div class="chapter">
-<!--070.png--><a name="Page_60" id="Page_60"></a><span class="pagenum">[Pg 60]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER II.</h3>
-
-<p class="center smaller">Works of construction: Earthworks, Culverts, Bridges, Foundations,
-Screw piles, Cylinders, Caissons, Retaining walls, and Tunnels.</p>
-
-<p class="p2"><strong>Earthworks.</strong>&mdash;Under this heading may be classified cuttings and
-embankments of earth, clay, gravel, and rock.</p>
-
-<p>When setting out a line and adjusting the gradients, an endeavour is
-usually made to so balance the earthworks that the amount obtained
-from the cuttings may be sufficient to form the embankments. With
-care, this may be effected to a considerable extent; but there will be
-places where the material from cutting is unavoidably in excess, and
-others where the cuttings are too small, or contain good rock, or
-gravel, which can be more advantageously used for building and
-ballasting purposes than for ordinary embankment filling. Or there may
-be a large cutting which will provide enough material to form three or
-four of the adjoining embankments; but the distance, or <em>lead</em>, as it
-is termed, to the far embankment may be so long, and, perhaps, on a
-rising gradient, that it would be cheaper to run the surplus cutting
-to <em>spoil</em>, and <em>borrow</em> other material for the far embankment from
-side cutting or elsewhere. A long lead adds materially to the cost and
-time of forming an embankment, as it not only necessitates a
-considerable length of <em>service</em>, or temporary permanent way, but also
-occupies much time in the haulage of the earth waggons. For distances
-of half a mile and upwards, a small locomotive is more suitable than
-horses for conveying the waggons.</p>
-
-<p>To run to <em>spoil</em> is the term applied to such of the material from a
-cutting which, not being required or utilized in the formation of the
-line embankments, is removed and tipped into mounds, or
-<em>spoil-banks</em>, in some one or more convenient sites near the mouth of
-the cutting. Sometimes the surplus material is disposed of by
-increasing the width of the embankments.
-<!--071.png--><a name="Page_61" id="Page_61"></a><span class="pagenum">[Pg 61]</span>
-Material excavated in a
-tunnel, and hoisted through the shafts to the upper surface, has to be
-deposited in spoil-banks along the centre line of the tunnel.</p>
-
-<p>To <em>borrow</em> material to form an embankment is the term used when the
-earthwork filling is not obtained from the cuttings
-on the line. This borrowing is generally done by excavating
-a trench on each side of the line, of such width and depth as
-will supply sufficient material to form the embankment. <a href="#fig47">Fig.
-47</a> gives an example of an embankment thus made from side
-cutting. In some cases a piece of high ground adjacent to the
-embankment can be utilized for obtaining a portion, or even
-the whole of the filling.</p>
-
-<p>Increased material is sometimes obtained by widening the
-cutting, or flattening the slopes, or both.</p>
-
-<p>The degree of slope of a railway cutting must be regulated by the
-nature of the material excavated. A slope of 1½ to 1, which gives for
-every foot of vertical height a width of one foot 6 inches of
-horizontal base, as in <a href="#fig47">Fig. 48</a>, is usually adopted for cuttings in
-ordinary earth, good clay, sand, or gravel. There are some
-descriptions of strong clay and marl which will stand at a steeper
-slope, even at 1 to 1; but, on the other hand, there are some kinds of
-clay which must ultimately be taken out to 2 to 1, and even 3 to 1.</p>
-
-<p>It frequently occurs that the slopes of a clay cutting, taken out to
-1½ to 1, appear to stand well for a time, but after exposure to the
-frost and rain of one or two seasons, the material becomes loosened,
-and forms into slipping masses, which slide down on to the line,
-stopping all traffic, and have to be cleared away before train
-operations can be resumed.</p>
-
-<p>Cuttings through solid rock may be taken out to a slope of ¼ to 1, as
-shown in <a href="#fig47">Fig. 49</a>, provided the material is compact, and there is not
-too great a dip in the strata or rock-beds. Where the rock-beds lie at
-a considerable angle, the slope on the high side will have to be made
-flatter than the slope required on the low side, as shown in <a href="#fig47">Fig. 50</a>,
-and great care must be taken to remove from the high side all loose or
-disconnected pieces of rock which might come away and slide down on to
-the line.</p>
-
-<div class="figcenter">
- <a name="fig47"></a>
- <img src="images/i062.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 47 through 51"
- title="Figures 47 through 51"
- />
-</div>
-
-<p>Strong dry chalk will generally stand at a slope of ⅓, or ½ to 1, but
-when wet and mixed with flints it will be necessary to increase the
-slope to not less than ¾ to 1. Where the rock is loose and
-disintegrated, a slope of not less than ½ or ¾ to 1 will be
-<!--072.png--><!--073.png--><a name="Page_63" id="Page_63"></a><span class="pagenum">[Pg 63]</span>
-required,
-and at many points there will be detached threatening masses of rotten
-rock which must be cleared away to a much flatter slope for safety. In
-cuttings of this description it is frequently found necessary to clear
-out a portion of the loose pieces of the lower cavities and build in
-their place a facework of masonry to support the superincumbent rock.
-Springs of water rising in the rock, or running over any part of the
-rock slopes, must be properly provided for, and conducted to the
-nearest channel. They should be carefully watched during the winter
-season, when the frost, acting on the water penetrating the crevices,
-splits and separates large pieces which were previously firm and
-secure.</p>
-
-<p>Instances will occur where a cutting has to be made through a thick
-bed of rock and several feet of soft loose strata underneath. The
-effect of forming a cutting through the soft strata is to induce the
-heavy bed of rock above to squeeze or force out the softer material
-below, and unless proper means were taken to avert such a disturbance,
-the entire cutting would have to be excavated to a very flat slope.
-The method adopted in such a case is to build strong face-walls of
-masonry, brickwork, or concrete, underneath the rock, as shown in <a href="#fig47">Fig.
-51</a>, with strong inverts placed at short distances. Suitable
-arrangements must be made to take away the drainage water which will
-collect at the back of the walls, and weeping-holes or outlets must be
-left in the lower part of the walls to convey the water into the
-water-tables on the line.</p>
-
-<p>Where there is a depth of earth cutting on the top of the rock, the
-earth should be cut away so as to leave a bench or space of 3 or 4
-feet between the edge of the rock cutting and the foot of the earth
-slopes, as shown on <a href="#fig52">Fig. 52</a>.</p>
-
-<p>In cases of shelving rock, with earth or clay on the top, as shown in
-<a href="#fig52">Fig. 53</a>, it is frequently found necessary to remove the whole of the
-clay on the high side to prevent the possibility of its sliding off
-the rock on to the line below.</p>
-
-<div class="figcenter">
- <a name="fig52"></a>
- <img src="images/i064.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 52, 53, 54, 55, 56"
- title="Figures 52, 53, 54, 55, 56"
- />
-</div>
-
-<p>In large cuttings it is usual to push forward a gullet of sufficient
-width for one or two lines of waggons, as shown in <a href="#fig52">Fig. 54</a>. When this
-has advanced some distance, strong planks or half balks of timber are
-placed across the gullet, and the sides or wings of the cutting can be
-excavated, the material wheeled to the gullet, and tipped from the
-barrows into the waggons beneath. By this arrangement the work can be
-carried on very
-<!--074.png--><!--075.png--><a name="Page_65" id="Page_65"></a><span class="pagenum">[Pg 65]</span>
-expeditiously, as one set of men can be engaged
-advancing the gullet and laying the track, while others are following
-up and taking down the sides. A large number of waggons can thus be
-filled in a day, and a small locomotive kept fully employed.</p>
-
-<p>Occasions will arise where the material from a large cutting, situate
-on a continuous gradient, as in <a href="#fig52">Fig. 55</a>, has to be carried in both
-directions to embankment.</p>
-
-<p>In wet weather, or if the cutting is at all wet, it would be almost,
-if not quite, impossible to carry on the excavation at the upper end
-to the proper formation level. The water would collect at the lower
-level, and not having any means of escape, except by pumping, would
-stop the work. In such a case the best way is to take out the cutting
-at the upper end to a slight rising gradient, as shown in the sketch,
-sufficient to carry away all water, and afterwards take out the lower
-portion in the working from the other end of the cutting.</p>
-
-<p>Cases will arise where it will be necessary to make a shallow cutting
-through boggy peaty ground. If the boggy material be very soft, and
-its thickness from the formation level to the solid ground below be
-not great, it may be advisable to remove this extra thickness down to
-the hard lower bed, and fill in up to formation level with strong
-material. If, however, the bog or peat be too thick to justify its
-entire removal, it should be excavated say down to two feet below
-formation level, and a thick layer of branches of trees and strong
-brushwood closely laid and packed the full width of the road-bed. On
-this preparatory foundation must be placed good clean ballast to carry
-the permanent way. Two or three extra sleepers should be allowed to
-the rail length, and in some instances it will be necessary to
-introduce two, or even four, rows of strong longitudinal timbers&mdash;half
-balks&mdash;under the transverse sleepers. The object of all this extra
-timber is to obtain a large increase of bearing area on the soft
-yielding surface of the boggy material. Notwithstanding these special
-precautions, the trackway will sink down a little during the passage
-of an engine or train, but will generally return to its former level.
-Good side drains or <a name="water5"></a>water-tables should be formed at each side of the
-cutting to take away all rain and surface water.</p>
-
-<p>In all cuttings it is desirable to have the line of formation on a
-slight gradient, sufficient to carry away all rain water or spring
-<!--076.png--><a name="Page_66" id="Page_66"></a><span class="pagenum">[Pg 66]</span>
-water which may be collected in the <a name="water6"></a>water-tables; but more
-particularly so is this necessary in a rock cutting, where the
-material, being non-absorbent as compared with earth or gravel,
-requires that all drainage must be carried away to the mouth of the
-cutting.</p>
-
-<p>In carrying out railway embankments and road approaches, it is usual
-to form the sides to a slope of 1½ to 1, as shown on <a href="#fig52">Fig. 56</a>.
-Occasionally the cuttings produce material which might stand at a
-rather steeper slope, but considering the effects which might
-afterwards be produced by heavy rains falling on the sides, it is more
-prudent to adopt the flatter slope of 1½ to 1. Some descriptions of
-clay will not stand at the above slope, but require a slope of 2 to 1,
-or even 3 to 1.</p>
-
-<p>When proceeding with the earthworks, it is customary to first remove
-and lay aside a layer, say 9 inches in depth, of soil and earth from
-the seat of the embankments and top widths of the cuttings, to be used
-afterwards in soiling the trimmed and finished slopes of the cuttings
-and embankments. This soil being removed, the actual work of the
-excavation can be commenced. The working longitudinal section will
-give all the necessary particulars as to position of the mouths of the
-cuttings and the depths at the various <a name="chain"></a>chain-pegs, and the top widths
-of the cuttings can be ascertained by calculation, if on even ground,
-or from the cross-sections if on side-lying ground, according as the
-material may be earth, clay, or rock.</p>
-
-<p>For facility of carrying on the works, reliable bench marks, or
-reduced level stations, must be established at convenient distances
-along the route of the line, and from these and the fixed chain-pegs
-the correct line of formation level can be checked from time to time
-as the work proceeds.</p>
-
-<p>For ordinary earth or clay cuttings, the usual tools are picks and
-iron crow-bars for loosening, or <em>getting</em> the material, and
-shovels for filling into barrows, carts, or waggons. For heavy
-earthworks, steam excavators are now largely employed. Great
-improvements have been made in this class of machinery, in the way of
-perfecting the method of excavating lifting, and filling the material
-into the earth-waggons.</p>
-
-<p>In nearly all rock cuttings the greater portion of the material has to
-be taken out, or loosened, by blasting with gunpowder, dynamite, or
-other explosive. The number and extent of the charges will depend upon
-the nature of the rock and its
-<!--077.png--><a name="Page_67" id="Page_67"></a><span class="pagenum">[Pg 67]</span>
-stratification, and also on its position
-as regards proximity to buildings or residential property.</p>
-
-<p>Where the rock is loose, or disintegrated, the pieces can generally be
-readily separated by picks and bars without having to resort to any
-great extent of blasting.</p>
-
-<div class="figcenter">
- <a name="fig57"></a>
- <img src="images/i068.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 57 through 66"
- title="Figures 57 through 66"
- />
-</div>
-
-<p>The first of the material excavated in the cuttings is generally
-conveyed in wheelbarrows to form the commencement of the adjoining
-embankments. When the wheeling distance becomes too far for economical
-barrow work, ordinary carts or three-wheeled carts, sometimes termed
-<em>dobbin carts</em>, are brought into operation where the cuttings and
-embankments are light; but where the earthwork is heavy, both in
-excavation and filling, a service or temporary road of light rails and
-sleepers is usually laid down to carry strong <em>tip</em> earth-waggons. For
-moderate distances these waggons are hauled by horses, but for
-distances over three-eighths of a mile a small locomotive is more
-speedy and economical. <a href="#fig57">Fig. 57</a> shows one form of dobbin cart; the
-wheels are made with good broad tyres, so as not to sink too deep into
-the soft ground, and the body being attached to the framework by a
-pivot or trunnion on each side, can be readily tilted over, and the
-earth tipped out, by releasing the holding-down catch. Where the
-ground is soft and wet, or of a very loose sandy nature, the work of
-hauling these dobbin carts is very heavy on the horses, and in such
-cases it soon becomes an advantage to lay down a service road of rails
-and sleepers. This service road is formed of light rails manufactured
-for the purpose, or old, worn rails no longer fit for main-line work,
-spiked down on to rough transverse wooden sleepers. The end of the
-embankment in course of formation, and where the earth is being
-tipped, is termed the <em>tip head</em>. Two or more roads are required at
-the tip head to form the embankment to its full width. <a href="#fig57">Fig. 58</a> gives a
-sketch plan of a service road near the tip head. The width is shown as
-for a double line. The earth-waggons are hauled along the line from
-the excavation, and brought to a stand at the point <strong>A</strong>. If a
-locomotive has drawn the waggons, it is then detached, moved forward,
-and shunted back into the siding <strong>BC</strong>. A horse accustomed to tipping
-then takes one full waggon at a time over one or other of the two
-turn-outs, <strong>DEF</strong> or <strong>DGH</strong>, to the tip head, sufficient impetus being
-given to the waggon to run the front wheels off the ends of rails on
-to cross-sleepers laid close, with a steep rise,
-<!--078.png--><!--079.png--><a name="Page_69" id="Page_69"></a><span class="pagenum">[Pg 69]</span>
-and backed up with
-earth. This suddenly checks the frame of the waggon, and the body
-containing the excavated material revolves on its trunnion, tilts up,
-and shoots out the material well forward, so that the man in charge of
-the tip head, who also knocks up the “tail-board catch,” is able to
-level off the filling without assistance. The empty waggon is then
-hauled back, and turned into the siding <strong>BC</strong>, and another full waggon
-taken forward and tipped, until all the waggons of the rake are
-emptied. Ten waggons generally form a rake when the work is pushed
-forward vigorously, each waggon holding about three tons. The <a name="tiphead"></a>tip head
-horse pulls the waggon by a trace-chain having a spring catch at the
-end, by which the driver releases the horse at the right moment. It is
-very important that this spring catch should be kept in good order,
-because occasionally too much impetus is given to a waggon, which,
-running over the tip head down the slope, would drag the horse with it
-if the spring catch did not act properly. Good firm foothold must be
-provided for the tipping horse.</p>
-
-<p>The tip head should never be carried across culverts or bridges until
-they have been well backed up, and protected by a thick covering of
-earth or clay, wheeled in with barrows to an equal height on each side
-of the masonry, so as to prevent undue side pressure.</p>
-
-<p><a href="#fig57">Fig. 59</a> gives a sketch of one form of end-tipping waggon. In some
-cases the wheels are made of cast-iron, but as these are readily
-broken during the rough handling to which <a name="earth">earth waggons</a> are exposed,
-it is questionable whether the light wrought-iron wheels, with light
-steel tyres, used on some works, are not more economical in the long
-run. The framework and body are made of strong undressed timber, well
-bound and bolted together. The tail-board catch keeps the body of the
-waggon in its proper horizontal position while loading or running, but
-when released leaves the body free to tilt up, and to revolve on the
-front trunnion by means of the circular clip <strong>A</strong>. The same principle
-is also applied to side-tipping waggons which are used for the
-widening of embankments, or formation of platforms and loading-banks.</p>
-
-<p>The permanent way of these service roads is generally made as simple
-as possible. A pair of movable rails are used instead of switches, as
-shown in <a href="#fig57">Fig. 60</a>. These rails are linked together by iron tie-rods,
-and pulled or pushed over into position for one
-<!--080.png--><a name="Page_70" id="Page_70"></a><span class="pagenum">[Pg 70]</span>
-or other of the roads
-by means of the handle at <strong>A</strong>. A stout iron pin, or iron
-clamping-plate, serves to retain the rails in position during the
-passing of the waggons. In a similar manner, a short rail working on a
-pin, or pivot, is made to answer the purpose of an ordinary crossing.
-The rails are laid complete and continuous for the one road, and for
-the second road the outer rail is laid sufficiently high to cross over
-the rail of the first road. A piece of rail is then secured by a
-centre pin, or pivot, to the cross-sleeper, as shown on <a href="#fig57">Fig. 61</a>. This
-pivoted rail is pulled over into the position shown by the dotted
-lines, to allow the passage of waggons on the one road, or pulled
-across to the end of rail at <strong>B</strong>, for waggons to pass on or off the
-other road. In the latter case an iron pin or clamp serves to keep the
-pivoted rail in position. As these service roads are merely laid down
-on the soft loose material brought forward for filling, they require
-constant packing and lifting to prevent them working into depressions,
-which might cause the waggons to leave the rails.</p>
-
-<p>To indicate the height of the embankment filling, strong stakes or
-poles must be firmly set in the ground at each chain-peg. On each of
-these poles two cross-bars must be fixed, the lower one placed to the
-correct height of the embankment, and the upper one to show the amount
-allowed for subsidence. The excavated material, as brought from the
-cuttings, is in a soft, loose condition, and an allowance must be made
-for its settlement, or subsidence, as the embankment becomes
-consolidated. This allowance will, of course, depend on the height of
-the embankment and the quality of the material, but for ordinary earth
-and clay it is customary to allow about one inch to the foot of
-height, which is equal to about 8 per cent.</p>
-
-<p>When forming embankments over very side-lying ground, it is necessary
-to cut steps in the sloping surface on which the filling material has
-to be placed, as shown in <a href="#fig57">Fig. 62</a>. These steps give a hold to the new
-earthwork, and check the tendency to slide down the hillside.</p>
-
-<p>Embankments have frequently to be carried over ground which is low,
-soft, and wet, but not boggy. If the culverts and drains are
-sufficiently large, and properly arranged, these places are not likely
-to cause much future trouble.</p>
-
-<p>For a thoroughly soft deep bog, however, it is most difficult to make
-any accurate calculation as to the amount of
-<!--081.png--><a name="Page_71" id="Page_71"></a><span class="pagenum">[Pg 71]</span>
-embankment filling which
-will be necessary to form a permanent foundation for the line; and the
-construction of a high heavy embankment across such a place is one of
-those undertakings which every engineer is most anxious to avoid. A
-large quantity of material may be tipped into the bog, and seem to
-stand fairly well for a time, and then suddenly disappear altogether.
-More material has to be brought forward, and will most likely
-disappear in a similar manner. The filling material being heavier than
-the bog on to which it is thrown, falls through, and displacing the
-soft semi-liquid matter, continues to sink down lower and lower until
-it is stopped by a harder stratum underneath. In a measure the
-operation somewhat resembles the tipping of earth into a lake; the
-material will go down until it meets with a solid bottom, and in going
-down it assumes its own natural slope, and forms for itself a width of
-base corresponding to its height. It will be readily understood what
-an enormous amount of filling material will be swallowed up in
-following out such a process. On a very soft bog, say 20 feet in
-depth, over which an embankment 20 feet high has to be formed, the
-extent of the actual earthwork filling will very probably closely
-approach the outline shown in <a href="#fig57">Fig. 63</a>. The upper portion, <strong>ABCD</strong>,
-representing the embankment proper, will contain about 133 cube yards
-to the yard forward, whereas the lower portion, <strong>CDEF</strong>, which has
-displaced the soft boggy matter, will contain about 266 cube yards to
-the yard forward, or, in other words, the filling which is out of
-sight will be double the filling which is in view above the section
-ground line.</p>
-
-<p>Apart from the large amount of filling consumed in forming this
-semi-artificial island, the progress of the work itself is very
-perplexing. A long length of the bank may have been raised again, once
-or twice, to the proper height, and may have carried rails and
-earth-waggons for some weeks, and then sink all at once several feet.
-The sinking, too, may not be uniform, but may produce fissures,
-depressions, and separation of the earthwork which will necessitate
-much care when bringing forward fresh filling material. The bog may
-not be of the same consistency throughout, there may be some layers of
-harder material, such as imbedded trunks of trees, and these may
-sustain the filling for a time, and then yield under the increasing
-weight of the superincumbent mass. Even when the embankment is
-finished throughout, and shows no sign of sinking, it should be very
-<!--082.png--><a name="Page_72" id="Page_72"></a><span class="pagenum">[Pg 72]</span>
-carefully watched for a long time for any indication of further
-movement.</p>
-
-<p>When the bulk of the material has been taken out of an earth or clay
-cutting, the work of trimming the slopes should be put in hand, so
-that any surplus left on the wings, or sides, may be removed, and
-carried away before stopping the earth-waggons. The angle of slope
-having been decided, a battering rule of light wooden boards is made
-to correspond to the slope, and in form similar to that shown in <a href="#fig57">Fig.
-64</a>. A plumb-bob is suspended from a fixed point, <strong>A</strong>; the lower end,
-<strong>B</strong>, is then held against a peg or mark which indicates the correct
-level and width of the cutting at the place, and the upper end, <strong>C</strong>,
-is raised or lowered until the plumb-bob string coincides with the
-vertical line marked on the rule from <strong>A</strong> to <strong>D</strong>, and the plumb-bob
-rests steadily in the space cut for it at <strong>D</strong>. With this battering
-rule a length of seven or eight feet, according to the size of the
-rule, is first trimmed to the correct slope, and by continuing the
-application of the rule up the side, a correct slope line is obtained
-from bottom to top of slope at that place. By repeating the process at
-convenient distances along the cutting, a series of correct slope
-lines are obtained, and the intermediate space can readily be trimmed
-to correspond.</p>
-
-<p>The same form of battering rule and method of working is applicable
-for trimming the slopes of the embankments.</p>
-
-<p>When the slopes of the cuttings and embankments have been trimmed,
-vegetable soil, which has been laid aside, or reserved as previously
-described, should then be spread evenly over the slopes to the uniform
-thickness of not less than four inches, and the whole sown with good
-grass seeds to form a strong sward.</p>
-
-<p>The trimming, soiling, and sowing of the slopes not only gives a more
-finished appearance to the earthworks, but the strong grass, when once
-well grown, binds the surface together, and helps to resist the
-injurious effects of heavy rains and melting snow.</p>
-
-<p>There are many places abroad where a neat finish to the earthworks is
-considered quite a secondary matter, or where it would be difficult to
-obtain suitable soil to spread on the slopes. The earthworks are
-hurried forward to allow the iron highway to be laid down as quickly
-as possible, the slopes of the cuttings and embankments are only
-roughly trimmed, and nature is left
-<!--083.png--><a name="Page_73" id="Page_73"></a><span class="pagenum">[Pg 73]</span>
-to supply such grass or vegetation
-as may spring up, or be self-sown.</p>
-
-<p>The fencing in of a line of railway serves the double purpose of
-defining the boundary of the company’s property, and of forming a
-barrier for the prevention of trespass of persons and animals on to
-the line. For our home lines, fencing is compulsory, and the same
-obligation exists on many foreign railways. In our colonies, and out
-in the far West of the United States, and in newly opened out
-countries, fencing, except near towns and villages, is rather the
-exception than the rule; people and animals roam at will from one side
-of the railway to the other wherever they find a convenient crossing
-place, and the cowcatcher of the engine has to be depended upon for
-throwing aside any animal which may be standing, or resting, on the
-line of rails at the passing of a train.</p>
-
-<p>The description of fence will be influenced by the locality, and the
-materials conveniently obtainable. Where stone is plentiful, perhaps
-brought forward out of the cuttings, and labour cheap, a masonry wall
-will be found a most suitable permanent fence. Any fence to be of
-service should not be less than four feet high. A wooden post and rail
-fence is much in favour in some districts, the posts being firmly set
-or driven into the ground, and four or five stout bars nailed on to,
-or set into, the upright posts. This fencing does not last very long,
-the pieces are small in size, and soon fail from decay. Quick or
-hawthorn hedges, when fully grown, make a good fence, but require
-careful attention to prevent gaps being made by roving cattle. They
-also require constant trimming and cutting. The quicks are generally
-planted in a mound formed by cutting a continuous ditch, or gripe, as
-shown in <a href="#fig57">Fig. 65</a>. The ditch serves as a drain to take away water
-running down the slopes of the embankments, small openings in the
-mounds, or drain pipes through them, forming leaders to conduct the
-water to the ditch or gripe. The outer edge of the ditch represents
-the boundary of the railway property, unless specially arranged
-otherwise.</p>
-
-<p>Galvanized iron-steel wire fencing, if not made too light, is strong
-and durable, and very easily kept in order.</p>
-
-<p>The wires may be secured to strong wooden posts, which should be
-creosoted, and not placed too far apart, or to iron posts or standards
-of angle iron or tee-iron section. The straining-posts,
-<!--084.png--><a name="Page_74" id="Page_74"></a><span class="pagenum">[Pg 74]</span>
-whether of iron
-or timber, must be stronger than the intermediate posts, firmly fixed
-into the ground, and well stayed, to withstand the pulling and
-tightening of the wires. There are many places where a quick fence
-would not grow, and where the ground is too soft to carry a wall. In
-such cases a good galvanized-wire fencing will fulfil all
-requirements. The strand wire is better than the plain wire, as its
-method of manufacture necessitates the use of a superior material, and
-it is easier to straighten and keep in good order. An extra strong
-fence is often made of six, eight, or more rows of round rod-iron
-secured to wrought-iron uprights of bar-iron or tee-iron.</p>
-
-<p>In hot countries abroad an excellent fence is obtained by planting a
-species of cactus or aloe in a similar manner to the quick fences at
-home, and as shown in <a href="#fig57">Fig. 66</a>. These cactus plants are readily
-obtained, are very hardy and quick in growth, and with their large
-spike-shaped leaves form such an almost impenetrable barrier that few
-animals will attempt to pass.</p>
-
-<p>Road approaches to bridges over or under the line, or to public road
-level crossings, may be fenced in the same manner as the line proper.
-If quicks are adopted, it will be necessary to put up a light wooden
-fence also to protect the young plants until they are well grown. Near
-towns and villages it is frequently found advisable to adopt a
-specially strong wooden fence, or close-boarded fence, where the
-approach is an embankment, and too newly made to carry a wall.</p>
-
-<p>Gates for farm or occupation level crossings may be made of wood or
-iron. As a rule, iron gates are preferred, as they can be supplied at
-the same cost as wood, and are very much more durable. Gates for
-public road level crossings have to be so placed that they will either
-close across the railway or across the road; their length will
-therefore depend upon the width and angle of the road crossing. It is
-better to make these gates of wood, so that, in the event of a train
-running through them, there may be less risk of injury to life and
-rolling-stock than if they were made of iron. For footpath crossings,
-small gates, wickets, or stiles may be adopted of such form as may be
-found most suitable for the requirements.</p>
-
-<p class="p2"><strong>Culverts and Drains.</strong>&mdash;Before proceeding with the formation of the
-embankments, it is necessary to construct the culverts and drains
-which will be covered over by the earthworks. Any existing drains
-which may be of too light a description must be
-<!--085.png--><a name="Page_75" id="Page_75"></a><span class="pagenum">[Pg 75]</span>
-reconstructed in a
-more substantial manner. It is a simple and comparatively inexpensive
-matter to rebuild a drain before the earth filling is brought forward,
-but it is a costly work to open out an embankment, and rebuild a
-culvert afterwards. Unless the seat of an embankment is well drained
-and kept free from the accumulation of running water, the earthwork
-will be exposed to washing away of the lower layers, and consequent
-subsidence. Each watercourse or open drain must be provided for either
-by a separate culvert of suitable size or, as may be done in some
-cases, by leading two or more watercourses into one, and thus passing
-all through one culvert of ample capacity. When fixing the sizes of
-the culverts they must not be limited to the normal flow of water, but
-a large margin must be allowed sufficient to meet extraordinary
-floods. The depth of the bed or invert of a culvert is a very
-important point. If laid too high, and the stream above should at any
-time deepen, the high invert would check the flow of the water, and
-would also incur the risk of being undermined and gradually carried
-away. If, on the other hand, the invert be laid too low, it will
-gradually silt up to the level of the stream-bed alongside, and there
-will be so much of the culvert space lost for all practical purposes.
-In cases when the invert of a culvert has to be laid at a special low
-depth to allow for future improvements in drainage, it is advisable to
-give extra height from the invert to the crown, or top, so as to
-provide ample waterway in the event of any silting up in the mean
-time. Particular care should be taken when building the foundation of
-a culvert. It has to be laid on the site of the watercourse, or on a
-new channel which will ultimately form the watercourse, and it should
-be built sufficiently deep into the ground to avert as far as possible
-the chance of water finding a course through below the foundation.</p>
-
-<p>The invert may be of stone pitching or brick if the current is not
-rapid, or liable to bring down stone boulders from its gravelly bed.</p>
-
-<p>With a stream-course having considerable fall, and which carries with
-it large stones, roots of trees, and other <i lang="fr">débris</i>, the invert should
-consist of strong pitching, composed of large-sized, rough-dressed
-stones of hard, durable quality, capable of withstanding the pounding
-of the boulders brought down during floods. A soft description of
-stone would be quite unsuitable for the invert of such a stream; the
-pitching would wear away
-<!--086.png--><a name="Page_76" id="Page_76"></a><span class="pagenum">[Pg 76]</span>
-quickly, break, and become detached, leaving
-the foundation and side walls exposed to the cutting inroads of the
-water.</p>
-
-<p>Where large flat bedded stones or flags of tough quality can be
-obtained, they form good covers, or tops, for culverts up to two feet
-in width. They should have not less than nine inches bearing on the
-side walls, and their contact edges should be fairly dressed, so as to
-fit sufficiently close to prevent the embankment filling from falling
-through.</p>
-
-<p>Where the stream, or run of water, is very small, strong earthenware
-pipes, 9 inches or 12 inches in diameter, well bedded, may be
-sufficient to carry away all the water likely to arise. For small
-springs in low swampy ground, dry stone drains may in many cases be
-used with advantage. These are made by cutting a trench, say two feet
-deep by twelve or eighteen inches wide, in the seat of the embankment
-from side to side, and filling it up with dry rubble stones, not
-boulders, hand-laid, the upper layer placed on the flat to keep the
-earthwork as much as possible from filling in between the stones.</p>
-
-<p>In soft boggy ground, where the depth to a hard bottom is very
-considerable, wooden culverts are frequently adopted. Although these
-cannot be classed as permanent structures, still, when they are made
-of sound well-creosoted timber, and substantially put together, they
-last for a number of years. Sometimes they are made cylindrical in
-section&mdash;a species of elongated cask with strong iron hoops every few
-feet. Others are rectangular in section, made with two strongly
-trussed side frames connected and covered with cross-planking and
-longitudinal tie-planking on the top and bottom.</p>
-
-<p>Wooden culverts are seldom made of very large size, rarely exceeding
-an opening of 3 feet, and it is considered preferable to use two of
-these culverts of moderate dimensions than one of large size. <a href="#fig67">Figs. 67</a>
-and 68 give sketches of wooden culverts of cylindrical and rectangular
-section, and <a href="#fig67">Fig. 69</a> of flag top culverts of 12-inch, 18-inch, and
-2-foot openings. In masonry culverts the side walls are shown to be of
-rubble stonework, but brickwork can be used instead, provided the
-bricks are well burnt, hard, and capable of withstanding the action of
-the water.</p>
-
-<div class="figcenter">
- <a name="fig67"></a>
- <img src="images/i077.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 67 through 71"
- title="Figures 67 through 71"
- />
-</div>
-
-<p>In <a href="#fig67">Figs. 70 and 71</a> are shown types of arch-top culverts of 4 feet and
-6 feet span respectively. The arch portion is shown to be of brick,
-which, as a rule, is cheaper than stone rings, which
-<!--087.png--><!--088.png--><a name="Page_78" id="Page_78"></a><span class="pagenum">[Pg 78]</span>
-must be cut and
-dressed to suit the small radius of the arch. The side walls may be of
-brick of good quality. Occasionally they are built of concrete. The
-wing walls may either be carried out in the direction of the stream,
-as in the sketch of the 6-foot culvert, or they may be built
-transverse, as shown on the 4-foot culvert, whichever arrangement is
-found to work in the best for the case in question.</p>
-
-<p>For arch culverts on very steep side-lying ground it is better to
-build the arch-top in steps, as shown in <a href="#fig72">Fig. 72</a>, instead of forming
-it parallel to the invert, or slope, of the stream-course. The level
-portions of the arching give a better hold for the embankment than
-could be obtained on a long inclined surface of brickwork or masonry.</p>
-
-<p>The writer has built a large number of culverts of this type for
-mountain streams on steep hillsides, and has found them to prove
-satisfactory in every way.</p>
-
-<p>In embankments alongside tidal rivers, or across the corners of
-estuaries of the sea, culverts have frequently to be so constructed
-that they will permit the passage of the drainage water from the land,
-or high side, without admitting the tidal water. This can be arranged
-by placing at the lower end of the culvert close-fitting hinged-flap
-valves opening outwards. When the tide has gone down the weight of the
-fresh, or land, water swings the flap-valve sufficiently open to allow
-of a free passage; and, on the other hand, when the tide rises, the
-pressure of the water against the face of the flap-valve keeps it
-tightly closed, and prevents ingress of the salt water.</p>
-
-<p>Culverts are sometimes fitted with lifting-valves or doors, which can
-be raised or lowered to serve irrigation purposes. The door, which
-works in guides, is made sufficiently heavy to fall with its own
-weight, and the raising is effected by means of a screwed
-suspension-rod working in a well-secured fixed nut.</p>
-
-<p>In cases of soft or treacherous ground, timber-piling or wide
-bed-courses of cement concrete are necessary to form firm foundations
-for culverts. Drains and streams which are intersected by a railway
-cutting have to be dealt with according to their size and their height
-above the finished rail level. The water from a small drain or field
-spring may be conducted in pipes down the slope of the cutting into
-the <a name="water7"></a>water-table, or side drain, at formation level, and will be thus
-carried away to the lower level at the entrance of the cutting. In
-many cases
-<!--089.png--><a name="Page_79" id="Page_79"></a><span class="pagenum">[Pg 79]</span>
-streams can be diverted, and the water led away to some
-lower point without the necessity of actually crossing the railway.
-With a large stream, where it is essential that the water should be
-conveyed across the line and continue on its ordinary course, it may
-be carried over in iron pipes or iron trough if there is ample
-headway, or in iron syphon pipes where the height is not sufficient.
-The iron pipes or trough can be supported on masonry or brick piers,
-or cast-iron columns, the height from the rails to the underside of
-the conduit being not less than that adopted for the over-line
-bridges.</p>
-
-<p>Occasionally the pipes can be carried across on an over-line bridge,
-either by placing them under the roadway or on small brackets outside
-the parapet.</p>
-
-<p>With the syphon arrangement the iron pipes must be laid down the
-slopes of the cutting and under the road-bed of the permanent way. The
-pipes must be continuous, strong, and firmly connected at the joints
-to prevent leakage. The inlet and outlet ends of the pipes should be
-securely built into receiving-tanks of masonry, brickwork, or
-concrete, to ensure an uninterrupted flow of the stream, and also to
-prevent any of the water from percolating through under the pipes and
-on to the railway. As a precautionary measure, it is well to place
-iron gratings some little distance in advance of the syphon pipes to
-intercept and collect any brushwood, straw, or other things which
-might be brought down with the stream.</p>
-
-<p><a href="#fig72">Fig. 73</a> gives an example of the syphon arrangement as constructed with
-two cast-iron pipes placed side by side.</p>
-
-<p>Railway works carried out in cities and large towns, whether they take
-the form of cuttings, embankments, arching, or tunnels, are certain to
-cause a very considerable disturbance of existing drains, corporation
-sewers, gas-pipes, water-mains and underground telegraph wires. Some
-of these underground works may be so peculiar and complicated as to
-necessitate a slight deviation from the course originally intended for
-the line. Suitable provision will have to be made for each of the
-items interfered with by the railway, and the substituted work must be
-carried out to the satisfaction of the constituted authorities within
-the municipal boundaries.</p>
-
-<div class="figcenter">
- <a name="fig72"></a>
- <img src="images/i080.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 72 and 73"
- title="Figures 72 and 73"
- />
-</div>
-
-<p class="p2"><strong>Bridges.</strong>&mdash;Amongst the many bridges and viaducts which have to be
-built during the making of a railway those constructed over rivers and
-waterways are generally the most important
-<!--090.png--><!--091.png--><a name="Page_81" id="Page_81"></a><span class="pagenum">[Pg 81]</span>
-The bridging across any
-navigable river or tidal water can only be effected in compliance with
-conditions imposed by the authorities controlling the navigation
-rights. These conditions will place restrictions as to the number and
-distance apart of the piers, as well as the height from high water
-level to the under side of the arches or girders. For rivers having a
-constant traffic of sea-going vessels of large tonnage and lofty masts
-the authorities will demand great height or headway as well as large
-spans; and if to this be added a deep water-way and bad foundations,
-the work to be constructed becomes one of considerable magnitude. The
-banks of the river must be carefully studied to find the most
-favourable point for crossing, and in some cases it may be prudent to
-make a detour of two or three miles. The crossing at a great height
-involves the construction of the approach lines at a great height
-also. If the river is in a deep valley with high sloping sides the
-natural contour of the ground facilitates the formation of the
-approach lines; but with a river on a low, wide, open plain, inclined
-approach lines add enormously to the cost of construction, as well as
-to the cost of permanent working.</p>
-
-<p>If the number of sailing craft passing up and down the river be
-moderate, and, perhaps, only passing at high water, the authorities
-may permit a low-level viaduct with an opening bridge.</p>
-
-<p>There are thus the two systems: the high-level viaduct, which allows
-trains to pass over and vessels to pass under at any and all times,
-and the low-level viaduct with opening bridge, which, if open for
-vessels, is closed for trains, or <i lang="la">vice versâ</i>.</p>
-
-<p>Every crossing of a navigable river will have to be considered and
-dealt with according to its own individual requirements. An
-arrangement suitable for the one may not be admissible or prudent for
-the other. A frequent and important train service might be much
-interfered with by an opening bridge, and, in a similar manner, an
-opening bridge might cause much interruption and detention to the
-navigation of the vessels on the river.</p>
-
-<div class="figcenter">
- <a name="fig74"></a>
- <img src="images/i082.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 74 through 77"
- title="Figures 74 through 77"
- />
-</div>
-
-<p>Where a low-level viaduct with opening bridge can be adopted, there
-will be a very great saving of expenditure; and there are numbers of
-such viaducts in existence, accommodating a large railway and river
-traffic without inconvenience. Even with a low-level viaduct the
-height from water-level to the
-<!--092.png--><!--093.png--><a name="Page_83" id="Page_83"></a><span class="pagenum">[Pg 83]</span>
-under side of the girders of the various
-fixed-spans will generally be sufficient for the passage of barges and
-small craft, leaving the opening portion to be used by the larger
-vessels.</p>
-
-<p>The principal openings for these large river viaducts are generally
-constructed for girders, partly on account of the greater facility of
-girder work for large spans, and also for the advantage of having one
-uniform height, or headway, from pier to pier.</p>
-
-<p>For a high-level viaduct across a deep-water river, the cost of the
-lofty piers forms a very important part of the undertaking. Each pier
-will require its own cofferdam, caisson, or other appliance for
-obtaining a suitable foundation. The deeper the water, the more costly
-the arrangement for foundation; and the higher the pier to rail-level,
-the greater the amount of material in the construction of the pier.
-The consideration of these two points will at once show that it is
-very desirable not to have more of these costly piers than is actually
-necessary, and in studying out the design it will be a question for
-calculation how far the spans may be increased so as to dispense with
-one or more piers.</p>
-
-<p>In every work of this description there is a relative proportion
-between span and height, which will give the most economical result
-from a cost point of view; the proportion varying according to the
-depth of the water and description of ground for foundations. An
-increase in the span will naturally necessitate an increase in the
-thickness of the pier; but where a cofferdam, or arrangement for
-putting in the foundations, must in any case be made, a small addition
-to its width may not necessarily form a large increase to its cost.</p>
-
-<p><a href="#fig74">Figs. 74, 75, 76, and 77</a> are sketches of high-level railway viaducts
-which have been constructed with great height, or headway, to allow
-large vessels to pass under at all times without interruption. This
-description of work is very costly, not only in the deep-water
-foundations, but also in the heavy scaffolding and appliances
-requisite for building piers and girders at such an elevation above
-the ground-level. The hoisting of the material alone forms an
-important item where such vast number of pieces have to be lifted to a
-height of 80, 90, or 100 feet.</p>
-
-<div class="figcenter">
- <a name="fig78"></a>
- <img src="images/i084.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 78 and 79"
- title="Figures 78 and 79"
- />
-</div>
-
-<p><a href="#fig78">Figs. 78 and 79</a> are sketches of low-level viaducts constructed with
-one large opening span, or swing-bridge, for the passage of vessels.
-The girders and roadway of such opening span are
-<!--094.png--><!--095.png--><a name="Page_85" id="Page_85"></a><span class="pagenum">[Pg 85]</span>
-usually constructed
-as a compact framework, which revolves on a centre placed in the
-middle of a circular roller path or species of turn-table. The
-portions of the rotating opening bridge, although not always the same
-length on each side of the centre-pin, are generally very carefully
-balanced, to preserve the equilibrium of the entire mass when swinging
-round for the passage of vessels. To ensure stability in working, and
-steadiness during heavy gales, a liberal diameter should be given to
-the roller path of all swing-bridges having large span and great
-weight.</p>
-
-<p>Lattice, or truss, girders are preferable to plate girders for
-swing-bridges of considerable opening, as they present less surface
-area to the action of the wind.</p>
-
-<p>The opening and closing of these bridges is effected by wheel-gearing
-actuated by hydraulic, manual, or other motive-power. The revolving
-machinery should be set solid and true, well protected from the
-weather, and, at the same time, readily accessible for constant
-inspection, lubrication, or repair.</p>
-
-<p><a href="#fig80">Figs. 80 to 85</a> are sketches of various types of railway bridges
-constructed for smaller openings across narrower rivers, water-ways,
-or canals. <a href="#fig80">Fig. 80</a> is an example of what is known as a <em>bascule</em>
-bridge. This particular bridge is made in two halves, meeting in the
-centre of the span, the tail end of each half being provided with
-heavy counterweights to assist in opening or tilting up the bridge for
-the passage of vessels, or lowering it down for railway traffic. Each
-half of the bridge swings on horizontal axles, and the raising or
-lowering is effected by means of hand winches or other motive-power,
-actuating wheel-gearing working into toothed vertical segments
-attached to the tail end of each half. The same principle has also
-been applied to bridges having only one leaf to tilt up to clear the
-passage way.</p>
-
-<p>Railway bridges of this pattern are now very rarely adopted. They have
-the great drawback that when raised to the vertical position, a very
-large area is presented to the action of the wind, and this defect
-might lead to very serious consequences in the case of a bridge
-situated in an exposed locality. An open-work floor diminishes the
-wind area, but a very large surface must necessarily remain.</p>
-
-<div class="figcenter">
- <a name="fig80"></a>
- <img src="images/i086.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 80 through 85"
- title="Figures 80 through 85"
- />
-</div>
-
-<p><a href="#fig80">Fig. 81</a> illustrates what is known as a <em>traversing bridge</em>. In this
-case the width of the opening passage-way and the
-<!--096.png--><!--097.png--><a name="Page_87" id="Page_87"></a><span class="pagenum">[Pg 87]</span>
-adjoining span are
-made the same, and the girders for the two spans are constructed in
-one continuous length. By means of gearing attached to the fixed
-portion of the work, the continuous length of girder, with its
-roadway, is first slightly raised or lowered, and then drawn back on
-rollers sufficiently far to leave the opening span quite clear for the
-passage of vessels. A reverse movement of the gearing causes the
-movable girders and roadway to travel back and return to their
-original position ready for the train traffic.</p>
-
-<p>Opening bridges are sometimes constructed on this system in cases
-where the level of the rails is only a few feet above the level of the
-water, and where there is only one water opening, and that not more
-than 20 to 30 feet wide. In such bridges the movable portion is rolled
-back along iron rails, or plates secured to masonry walls, or strong
-pile-work. This class of bridge is cumbersome, slow to move, and is
-now but very rarely adopted.</p>
-
-<p><a href="#fig80">Fig. 82</a> shows a type of simple <em>lift</em> bridge, of which there are but
-few examples remaining. In this particular bridge the girders and
-roadway form a solid framework, which rests on the abutments during
-the passage of the trains. Strong chains, secured to the corners of
-the framework, pass over large sheaves on the top of the iron
-standards, and then round drums placed below the level of the rails,
-and terminate by attachment to heavy counter-weights suspended in iron
-cylinders. The counter-weights are adjusted to approximately balance
-the bridge, so that a moderate power applied to the wheel-gearing on
-the drums is sufficient to raise the roadway to the required height.
-This class of opening bridge is only suitable for the passage of
-barges and small craft without masts; and it requires the
-re-adjustment of the counter-weights when the roadway varies in
-weight, in consequence of rain or repairs.</p>
-
-<p><a href="#fig80">Figs. 83, 84, and 85</a> are sketches of small <em>swing</em>-bridges constructed
-for narrow waterways. Although differing in appearance, they are all
-practically on the same principle, with centre pin and roller path,
-and are similar in general arrangement to the large-size-opening
-swing-bridges shown in <a href="#fig78">Figs. 78 and 79</a>.</p>
-
-<div class="figcenter">
- <a name="fig86"></a>
- <img src="images/i088.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 86 through 88"
- title="Figures 86 through 88"
- />
-</div>
-
-<p>The <em>swing</em>-bridge arrangement is so simple in construction,
-convenient for inspection, and easy to maintain, that where possible
-it is now generally adopted in preference to any other
-<!--098.png--><!--099.png--><a name="Page_89" id="Page_89"></a><span class="pagenum">[Pg 89]</span>
-system. The
-weights on centre pin and roller path may be distributed as considered
-most expedient, and by means of suitable appliances the weight may be
-altogether taken off the centre and rollers when the bridge is closed
-for the passage of trains.</p>
-
-<p>There are many wide rivers which, although not navigable in the
-ordinary acceptance of the term, nevertheless require bridges of large
-spans to provide free waterway for the floating down of rafts of
-timber. Away in the high ground, in the timber-growing districts,
-trees are felled, sawn or cut into long poles, logs, or scantlings,
-and hauled to the banks of the river. The timbers are then formed into
-large rafts of the most convenient form for floating down to the place
-of distribution or port for shipment. Even with old experienced
-floaters, using their long sweeps in the most skilful manner, it is
-difficult to take anything but a very irregular course down the
-stream. Under the most favourable circumstances one of these large
-rafts is an unwieldy, awkward craft to manage; but in a river full of
-twists and turns, with reaches varying from comparative smooth water
-to miniature rapids, the current carries the huge mass surging along,
-and only a clear, unobstructed channel will enable its navigation to
-be carried out with safety. The presence of a pier in the main
-waterway might cause destruction to the rafts and loss of life to the
-men. The vested interests in floating rights are tenaciously guarded,
-and no new bridge would be sanctioned which would in any way interfere
-with the waterway or endanger the passage of rafts down the river.
-Bridges of this description are much less costly than those over deep
-water&mdash;navigable rivers. Excepting the large spans, the rest of the
-work is comparatively simple. The water is generally shallow, and much
-reduced in quantity during the summer months. Good foundations can
-generally be obtained without going to any great depth. The headway
-may be kept low, or of such height as may best suit the purposes of
-the railway, and be sufficiently well up out of the way of the floods
-which may take place from time to time on the river.</p>
-
-<div class="figcenter">
- <a name="fig89"></a>
- <img src="images/i090.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 89 and 90"
- title="Figures 89 and 90"
- />
-</div>
-
-<p><a href="#fig86">Fig. 86</a> is a sketch of a bridge constructed over a river much used for
-rafting purposes. The large span is over the main channel, and the
-small spans are over a wide gravelly foreshore, which is only covered
-with water during exceptionally high
-<!--100.png--><!--101.png--><a name="Page_91" id="Page_91"></a><span class="pagenum">[Pg 91]</span>
-floods in the autumn or winter.
-No rafting can be carried on when the river is in flood; the current
-would be too strong to permit of the raft being kept under control.</p>
-
-<p><a href="#fig86">Fig. 87</a> is a sketch of a similar bridge where the river is confined to
-a regular channel between two sloping banks of strong clay.</p>
-
-<p><a href="#fig86">Fig. 88</a> shows a bridge erected over a narrow rocky pass in the river.
-The channel is hemmed in by the almost perpendicular sides of mountain
-granite, there are no banks to overflow, the flood waters cannot
-spread laterally, however much they may increase in depth, and with
-building-stone at hand in abundance, and foundations formed in the
-solid rock, the situation is one of the most favourable for a strong
-permanent bridge. The cast-iron arch of 150-feet span has a graceful
-appearance, and harmonizes well with the surrounding scenery. A small
-masonry arch at each end of the bridge provides for communication
-along the banks of the river.</p>
-
-<p>With rivers which are neither under the control of navigation
-authorities nor used for rafts of timber, there is much greater
-freedom for the designing and carrying out of bridges or viaducts
-suitable for the actual physical conditions of the locality. The
-headway will be guided only by the height of the railway to be carried
-across, and by any flood-water levels which may affect the work. The
-size of the spans will be regulated by the width of the river, the
-depth of the water, and the nature of the ground into which the piers
-have to be built. For broad, shallow rivers with good firm river-beds,
-piers may be built at moderate cost, and comparatively small spans
-adopted; on the other hand, with a broad deep river it will be better,
-as previously explained, to reduce the number of piers and increase
-the span. In the one case, for example, a river 150 feet wide may be
-crossed with three spans and two piers in the shallow water, as in
-<a href="#fig89">Fig. 89</a>; in the other it may be more prudent and economical to cross
-in one span, without any intermediate pier, as shown in <a href="#fig89">Fig. 90</a>.</p>
-
-<div class="figcenter">
- <a name="fig91"></a>
- <img src="images/i092.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 91"
- title="Figure 91"
- />
-</div>
-
-<p>Next in importance to the large bridges and viaducts over rivers are
-the viaducts which have to be constructed for the crossing of deep
-inland valleys. The occurrence of one of these deep valleys between
-long lengths of average table-land renders necessary either a series
-of cuttings and falling gradients to get down to a low level, or the
-erection of high-level works
-<!--102.png--><!--103.png--><a name="Page_93" id="Page_93"></a><span class="pagenum">[Pg 93]</span>
-to continue onward the rail-level at the
-height already attained. A decision to adopt the latter course brings
-forward the consideration as to the method of carrying out the work.
-To form a high embankment across such a valley would entail an
-enormous expenditure for earthwork, and several openings, or bridges,
-would have to be made in the embankment for streams, rivers, and
-roadways. Instead, therefore, of making this part of the line entirely
-of embankment, it is usual to carry the earthwork forward until the
-height is about 25 or 30 feet, and to form the remainder of the
-opening of arching, as shown in <a href="#fig91">Fig. 91</a>.</p>
-
-<p>This arrangement is not only less costly than an embankment of such
-height, but has also the great advantage that any or all of the arches
-are available for the passage of streams, rivers, roads, and
-accommodation works.</p>
-
-<p>The character of the work to be carried out in the construction of
-bridges or viaducts over rivers or valleys must greatly depend upon
-the description of materials at command. Where good building-stone is
-plentiful, and the price of labour moderate, works of masonry should
-be adopted as far as practicable. Brickwork is an excellent substitute
-for masonry, provided that specially selected bricks are used for all
-facework, or parts exposed to the weather. For water-washed piers and
-abutments, the lower portion should be faced with good hard stone.</p>
-
-<div class="figcenter">
- <a name="fig92"></a>
- <img src="images/i094.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 92"
- title="Figure 92"
- />
-</div>
-
-<p>Bridges and viaducts consisting of arches of masonry or brickwork form
-the most substantial and permanent works of construction for railway
-purposes; once properly built, the expenditure on future maintenance
-or repairs is merely nominal. For viaducts the span of the arching
-must be regulated by the height of the viaduct. The greater the height
-the larger the span. In one case 30-feet spans may be suitable,
-whereas in another it may be more economical to introduce spans of 60
-feet or more, and so reduce the number of lofty piers. From a cost
-point of view there is, however, a limit to the span of arching, and,
-except for special cases, where expenditure is of secondary
-importance, large spans are very rarely adopted. Arches of large
-spans, no doubt, have been built both in masonry and brickwork, and
-have been a complete success in every way except expense.
-Unfortunately, the quantity and weight of materials in arching, and
-the corresponding cost, increase
-<!--104.png--><!--105.png--><a name="Page_95" id="Page_95"></a><span class="pagenum">[Pg 95]</span>
-very rapidly as the span increases,
-and for openings of more than 60 or 70 feet girder-work becomes much
-cheaper than arching.</p>
-
-<p><a href="#fig92">Figs. 92</a> and <a href="#fig93">93</a> are examples of viaducts having piers of masonry, with
-girders to carry the roadway. In the one case the roadway is carried
-on the bottom flange of the girders, and in the other on the top. The
-latter arrangement affords greater facility for securely bracing the
-girders together, while for the former it is claimed that the girders
-form a massive parapet, which would serve as a protection in the event
-of an engine or vehicles leaving the rails.</p>
-
-<p>In the early days of railways, many large viaducts were constructed
-having masonry piers, and timber trusses to carry the roadway. Much
-ingenuity was displayed in designing the trusses, and in the
-introduction of cast-iron joint-shoes and wrought-iron bracings. Many
-of these wooden superstructures served well for several years, but
-they were always exposed to the imminent risk of destruction from
-fire, and however carefully the logs may have been selected, the decay
-of the timber was only a question of time. The deterioration of one
-piece was equivalent to the weakening of the entire truss, and the
-renewal of any part was both difficult and costly. The shrinkage of
-the timber, and the working at the joints, caused the trusses to
-deflect considerably under a passing load, and although the actual
-strength of the structure may not have been much impaired, the
-creaking and depression had anything but a reassuring effect. Timber
-superstructures for anything but small spans are rarely adopted now,
-except for temporary works, or on lines abroad, where the transport on
-girder-work would be very costly, and where good timber is very cheap
-and abundant. Even in the latter case the wooden superstructure is
-generally looked upon as a temporary expedient, to be replaced at no
-very remote date with iron or steel girders, when the materials can be
-conveyed over the entire completed line.</p>
-
-<p><a href="#fig94">Figs. 94, 95, and 96</a> are sketches of three types of timber trusses as
-constructed in viaducts of several spans.</p>
-
-<div class="figcenter">
- <a name="fig93"></a>
- <img src="images/i096.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 93"
- title="Figure 93"
- />
-</div>
-
-<p>There are many localities, especially abroad, where suitable stone is
-most difficult to obtain, and very expensive to work and convey. In
-such cases it is compulsory to use as little of it as possible, and to
-resort to iron or steel both for the girders and a large portion of
-the piers. The piers may be made of cast-iron,
-<!--106.png--><!--107.png--><a name="Page_97" id="Page_97"></a><span class="pagenum">[Pg 97]</span>
-wrought-iron, or steel,
-of suitable form and arrangement to ensure strength and stability. Not
-only must the piers be strong enough to carry the weight that may be
-brought upon them vertically, but they must have sufficient width of
-base to ensure lateral steadiness. The design should admit of facility
-of erection, with a minimum of scaffolding, and the pieces should be
-of convenient length and weight for transport. The lower length of
-river piers, or portion liable to be in contact with flood-water,
-should be of solid masonry, to resist the action of the water, or of
-any <i lang="fr">débris</i> brought down by the current. More than one fine
-viaduct has been swept away for want of due attention to the latter
-precaution.</p>
-
-<p><a href="#fig97">Fig. 97</a> illustrates a type of pier composed of cast-iron columns, well
-braced and stayed with wrought-iron. The ends of the columns and all
-contact surfaces should be properly turned and faced by machinery to
-ensure true and perfect joints, and the socketed ends should be turned
-and bored to fit closely. The latter is important, and if not
-carefully carried out, a slight sliding movement of the flanges may
-take place, and throw undue strain on the bolts.</p>
-
-<p><a href="#fig97">Fig. 98</a> shows a very similar pier, constructed entirely of
-wrought-iron or steel.</p>
-
-<p>Each of the above-described piers has a liberal amount of taper or
-batter, both in the front and transverse elevation.</p>
-
-<p>The size and number of the columns, and the dimensions of the braces
-or stays, will depend upon the height of the pier and the weights and
-strains to be sustained.</p>
-
-<p>Many important and lofty viaducts have been erected on this principle
-of iron piers springing from masonry foundations, more particularly
-across deep rugged ravines abroad, where iron piers offered the only
-practical, substantial means of dealing with what appeared otherwise
-an impossibility.</p>
-
-<div class="figcenter">
- <a name="fig94"></a>
- <img src="images/i098.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 94, 95, 96, 101"
- title="Figures 94, 95, 96, 101"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig97"></a>
- <img src="images/i099.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 97 and 98"
- title="Figures 97 and 98"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig99"></a>
- <img src="images/i100.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 99"
- title="Figure 99"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig100"></a>
- <img src="images/i101.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 100"
- title="Figure 100"
- />
-</div>
-
-<p><a href="#fig99">Fig. 99</a> is a sketch of the Kinsua Viaduct on the Erie Railway, one of
-the highest railway viaducts in the United States. In the transverse
-elevation the piers have a large amount of taper; but in the front
-elevation they are vertical, and of width to correspond to one of the
-small spans of the main girder. This arrangement of long and wide base
-gives great stability to the pier. The spans of the girders, which are
-of the ordinary lattice type, are not large, being 61 feet for the
-clear spans, and 38 feet 6 inches for those over the piers. The
-principal interest is in
-<!--108.png--><!--109.png--><!--110.png--><!--111.png--><!--112.png--><a name="Page_102" id="Page_102"></a><span class="pagenum">[Pg 102]</span>
-the great height and simplicity of the piers.
-The rail-level over the top of the pier is 301 feet above the level of
-the water in the Kinsua stream. The width of this pier on the top is
-10 feet (for single line), and the width at the bottom 103 feet.</p>
-
-<p><a href="#fig100">Fig. 100</a> is a sketch of the Loa Viaduct on the Antofagasta Railway,
-Bolivia, stated to be the highest railway viaduct in the world. The
-arrangement of spans and piers is very similar to the Kinsua Viaduct.
-The main spans are 80 feet, and the pier spans 32 feet. The width of
-the pier on the top is 10 feet 6 inches (for single line), and the
-width at the bottom of the highest pier is 106 feet 8 inches.</p>
-
-<p>In contrasting these light iron piers with what would have been
-required if constructed of masonry, an idea may be formed of the
-enormous amount of material, labour, and time, which would have been
-expended to erect the work in stone.</p>
-
-<p>Before the principle of lofty iron piers had been thoroughly
-developed, many high piers had been built of timber both at home and
-abroad. More particularly was this the case in the United States of
-America, where the presence of magnificent timber close to hand
-offered special inducements for the use of wood. Like a mammoth
-scaffolding, each pier was constructed with a most liberal supply of
-material, judiciously selected and carefully put together, but the
-danger of destruction by fire was ever present from the beginning.
-Probably more timber piers and bridges have been destroyed by fire
-than have been removed on account of natural decay.</p>
-
-<p>One of the most notable of these timber-pier constructions was that of
-the Old Portage Viaduct, on the Erie Railway, U.S.A. <a href="#fig94">Fig. 101</a> is a
-sketch of one or two of the piers. This viaduct was more than 800 feet
-long, and 234 feet high from the bed of the river to the rail-level.
-The spans were 50 feet each. Masonry piers were carried up to about 25
-feet above the ordinary water-level of the river, and upon these the
-timber superstructure was erected. Each timber pier consisted of three
-complete sets of framework, securely connected together, and also well
-stayed and braced to the adjoining piers. This viaduct was destroyed
-by fire in 1875, and was reconstructed with piers and girders of iron.</p>
-
-<p>Railway bridges over or under public roads of primary or secondary
-importance must be constructed to the widths and heights prescribed
-for such works in the fixed regulations of the
-<!--113.png--><a name="Page_103" id="Page_103"></a><span class="pagenum">[Pg 103]</span>
-country in which they
-have to be built. As a rule, these road-bridges are simple and
-inexpensive in character, except in towns, or in cases where the line
-crosses the roads very obliquely, or where the road is situated at the
-top of a deep cutting, or bottom of a high embankment. Away from towns
-and out in the open country, permission is generally obtained to
-divert the roads to a moderate extent, so as to obtain a more
-favourable angle and height for the bridge; but in towns, where the
-roads become streets, sometimes of great width, with houses and shops
-on each side, little or no diversion can be allowed.</p>
-
-<p>A railway passing through a portion of a densely populated town must
-deal with the streets as they exist, as any great alteration in their
-course or continuity would involve a large destruction of property.
-With careful laying out it is possible to obtain favourable crossings
-for many of the streets, but a number of others must be crossed
-obliquely, and these oblique crossings very frequently result in a
-span twice the width, or even more, of what would be necessary to
-cross the street on the square. Bridge-work in towns is more costly
-than in the country, as a higher class of work is demanded, more
-finish or dressed work in the masonry or brickwork, and more
-ornamentation in the screens and parapets in connection with the iron
-girder-work. The work itself has to be carried on in a confined
-locality, with limited space for materials and appliances, and where
-the thoroughfare must be kept open.</p>
-
-<p>Where the height is sufficient, and suitable materials readily
-obtained, it is preferable to adopt an arch bridge, as being of a much
-more permanent character than girders.</p>
-
-<p><a href="#fig102">Fig. 102</a> is an example of an ordinary over-line arch bridge to carry a
-public road over a double line of railway in a cutting of moderate
-depth.</p>
-
-<p><a href="#fig103">Fig. 103</a> shows a somewhat similar over-line arch bridge, but its
-height from rail to road-level being greater, side arches are
-introduced in preference to long heavy wing walls.</p>
-
-<p><a href="#fig104">Fig. 104</a> shows an over-line arch bridge in a rock cutting. In this
-case, by increasing the span and forming the springing bed in the
-solid rock, the masonry of abutments and wing walls may be reduced to
-a minimum.</p>
-
-<p><a href="#fig105">Fig. 105</a> is a sketch of an ordinary under-line arch bridge to carry a
-railway over a public road in an embankment of moderate height.</p>
-
-<div class="figcenter">
- <a name="fig102"></a>
- <img src="images/i104.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 102, 128, 129, 130 "
- title="Figures 102, 128, 129, 130"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig103"></a>
- <img src="images/i105.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 103"
- title="Figure 103"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig104"></a>
- <img src="images/i106.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 104"
- title="Figure 104"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig105"></a>
- <img src="images/i107.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 105"
- title="Figure 105"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig106"></a>
- <img src="images/i108.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 106"
- title="Figure 106"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig107"></a>
- <img src="images/i109.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 107"
- title="Figure 107"
- />
-</div>
-
-<p><!--114.png--><!--115.png--><!--116.png--><!--117.png--><!--118.png--><!--119.png--><!--120.png--><a name="Page_110" id="Page_110"></a><span class="pagenum">[Pg 110]</span>
-<a href="#fig106">Fig. 106</a>
-shows a similar under-line bridge, but with curved instead of straight
-wing walls.</p>
-
-<p><a href="#fig107">Fig. 107</a> is an example of an under-line arch bridge in a rather high
-embankment, and where side arches have been adopted instead of long
-wing walls.</p>
-
-<p>The above six types are equally applicable for private roads crossing
-the railway, but, as previously mentioned, a lesser width and headway
-will be accepted for under-line bridges for private or occupation
-roads, than for public roads. For the over-line bridges, however, the
-width and headway will be regulated by the number of lines and
-standard height of the railway.</p>
-
-<p>When these arch bridges have to be built on the skew to suit an
-oblique crossing of the road, extra care will be necessary in setting
-out the work, and marking on the centering the spiral courses of the
-arching.</p>
-
-<p>Arch bridges may be built of masonwork or brickwork, or a combination
-of the two. If the available quarries do not yield good flat bedded
-stones readily worked, it is better, where possible, to use strong
-hard bricks for the arching, and utilize the stone for the remainder
-of the work.</p>
-
-<p>Although arching undoubtedly forms the most durable type of
-bridgework, numbers of cases occur where the available height or space
-between rail-level and road-level is too small, or the cost of masonry
-and brickwork too great, to admit of anything but girder-work.
-Detailed sketches of some of the many forms of girder bridges are
-given in <a href="#fig132">Figs. 132</a> to <a href="#fig153">153</a>, illustrating various systems of roadways
-and parapets. In some instances the main girders are made sufficiently
-deep to serve as parapets, while in others a shallower girder has been
-adopted, on top of which has been placed a light cast-iron parapet
-composed either of close plate-work or of ornamental open railings.
-The open ironwork parapet has a good appearance, but as a screen is
-not so efficient as the close cast-iron plates.</p>
-
-<p>In addition to the bridges required for the regular public roads, it
-is usually necessary to construct a certain number of occupation or
-private road bridges over and under the line to accommodate portions
-of estates and large properties intersected or severed by the railway,
-and which would be inadequately provided for by ordinary gate
-crossings on the level. The position and description of these
-occupation bridges is generally matter of private arrangement. The
-bridges will be somewhat
-<!--121.png--><a name="Page_111" id="Page_111"></a><span class="pagenum">[Pg 111]</span>
-similar in character to the public road
-bridges, but of much less width for the roadway. Those over the
-railway must have the standard span and height adopted as a minimum
-for the other over-line bridges, and those under the railway must have
-the full width on the top for the lines of rails, but will have less
-width between the abutments for the roadway.</p>
-
-<p class="p2"><strong>Foundations.</strong>&mdash;So much depends upon the soundness and security of the
-foundations of any bridge, viaduct, or large building, that it would
-be almost impossible to devote too much care to the selection and
-treatment. Unless the foundation be firm, the entire structure will be
-exposed to the risk of failure, either in subsidence of masonry,
-giving way of arches, or depression of girders. A small matter
-overlooked during the construction of this part of the work will be
-most difficult to correct or adjust afterwards.</p>
-
-<p>The insistent weight of all structures built of masonry or brickwork
-will cause the mass to settle to a certain extent, according as the
-joints of mortar or cement become compressed by the number of
-superincumbent courses. In a similar manner the gravel and clay of a
-foundation will compress more or less according to its compactness and
-the weight of the structure. No inconvenience will, however, arise if
-the settlement or compression be uniform throughout the entire area.</p>
-
-<p>In ordinary average, dry, solid ground, a good foundation can usually
-be obtained at a moderate depth. The removal of a few feet of the
-surface layers will generally lead to a good hard stratum of natural
-material sufficiently firm to carry the abutments and piers of railway
-bridges and viaducts. Two or more footings are usually adopted so as
-to distribute the weight over an increased area, as shown in <a href="#fig108">Fig. 108</a>.</p>
-
-<p>Where the weight to be carried is considerable, it is better to
-increase the number of the footings, and give them a smaller
-projection, as in <a href="#fig108">Fig. 109</a>, rather than have a lesser number and
-greater projection, as in <a href="#fig108">Fig. 108</a>. There is greater liability of
-fracture of the material in the latter than in the former.</p>
-
-<p>Care must be taken to distinguish between made ground and natural
-ground. Hollows which have been filled in must not be relied upon to
-sustain heavy weights; the material may have been consolidating for
-years, but it is safer to cut through it and found upon the natural
-stratum beneath.</p>
-
-<div class="figcenter">
- <a name="fig108"></a>
- <img src="images/i112.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 108 through 111, 113 - 115, 124, 125"
- title="Figures 108 through 111, 113 - 115, 124, 125"
- />
-</div>
-
-<p>Soils of a clayey nature must be dealt with very cautiously.
-<!--122.png--><!--123.png--><a name="Page_113" id="Page_113"></a><span class="pagenum">[Pg 113]</span>
-If the
-ground be fairly level, and the material firm, a solid foundation may
-be obtained, but the excavated portion should be covered up as quickly
-as possible to prevent any decomposing action taking place upon
-exposure to the open air. The expansive nature of some clays must be
-carefully kept in view, so as to guard against any disturbance in the
-finished foundation. There are some descriptions of shale which when
-first opened out appear to have the solidity of hard rock, and yet,
-after a few days’ exposure to the atmosphere, are changed to the
-consistency of soft mud.</p>
-
-<p>Sand, being composed of such small particles, is almost incompressible,
-and makes an excellent foundation so long as it can be retained in its
-position. Little or no settlement will take place if the sand remains
-undisturbed, but so soon as it comes under the influence of running
-springs, or underground drainage, the fine particles of the sand will
-be gradually but surely carried away with the water, and the entire
-foundation be undermined. The opening out of a neighbouring
-excavation, or the carrying out of some low-level drainage, would
-endanger a construction which otherwise would be solid and permanent.</p>
-
-<p>In many cases of soft ground, more particularly abroad, sand piles
-have been adopted and have given very good results. The system is
-carried out by first driving a large wooden pile down through the soft
-material into the more solid stratum below. The timber pile is then
-carefully withdrawn and the cavity filled with clean sand. The number
-and distance apart of these sand piles will depend upon the nature of
-the ground and description and weight of structure to be carried.</p>
-
-<p>Clean, compact gravel is one of the best materials to build upon,
-being almost incompressible and quite unaffected by exposure to the
-atmosphere. It is easily excavated and levelled off to the surface
-required.</p>
-
-<p>A foundation of rock may be considered in the abstract as the most
-solid base to be obtained, but it must be treated judiciously, and a
-proper surface secured. The outer portion of many descriptions of rock
-consists of blocks or layers of stone partially or entirely separated
-from the main bed, and these, lying in a loose condition, are
-deceptive and treacherous as a foundation base. The exposed rock
-should be carefully examined, and all detached or outlying pieces or
-layers removed before placing any foundation course. Special care must
-be paid to all
-<!--124.png--><a name="Page_114" id="Page_114"></a><span class="pagenum">[Pg 114]</span>
-shelving rock, and a level seating cut into it for the
-entire width of the foundation, as shown in <a href="#fig108">Fig. 110</a>.</p>
-
-<p>A thick bed of concrete, as in <a href="#fig108">Fig. 109</a>, makes an excellent foundation
-course. When firmly set it becomes one solid massive base from end to
-end, and prevents the yielding or dropping of masonry at any
-intermediate points.</p>
-
-<p>There are many places in soft, wet ground where instead of attempting
-to excavate all the soft material down to a harder stratum, it is
-better to adopt timber pile foundations, as shown in <a href="#fig108">Fig. 111</a>. The
-size of the piles and their distance from centre to centre must be
-regulated by the description of material into which they have to be
-driven and the weight they have to sustain. Double waling pieces
-should be properly checked and bolted on to the heads of the piles,
-and trimmed or levelled off to receive a double floor of thick planks.
-The spaces round the heads of piles and walings should be filled in
-and levelled up to under side of flooring, with cement concrete.</p>
-
-<div class="figcenter">
- <a name="fig112"></a>
- <img src="images/i115.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 112"
- title="Figure 112"
- />
-</div>
-
-<p>For bridges of moderate span, over soft ground or over shallow fresh
-water, strong cast-iron screw piles can be adopted with great
-advantage. <a href="#fig112">Fig. 112</a> shows a very usual form of screw pile, made with
-an external screw at the lower end and with a sharp cutting edge to
-facilitate penetration into the ground. The upper portions are made in
-suitable lengths, and all to one pattern and template, for convenience
-in carrying out the work. The screwing into the ground is generally
-effected by means of a capstan or cross-head fixed to the top of the
-first working length of pile, and which is pulled or turned round by
-ropes worked from stationary windlasses. In some cases long bars or
-levers are attached in radiating positions to the capstan-head, and a
-number of men are employed to walk round and round, pushing the
-levers, and in this way screwing the pile into the ground. As the pile
-goes down the capstan-head has to be removed, and additional lengths
-bolted on, until the pile enters a solid stratum, or is considered
-deep enough for the duty it has to perform. The last or top length has
-generally to be cast to a special length to bring the work up to the
-exact height to receive the girders. The core of excavated material
-passes up into the interior of the pile, and in some cases becomes so
-compressed or tight as to require the use of an internal augur to
-remove a portion of it to enable the screwing to proceed. The pile
-shown in <a href="#fig112">Fig. 112</a> is one of a number which were successfully screwed
-<!--125.png--><!--126.png--><a name="Page_116" id="Page_116"></a><span class="pagenum">[Pg 116]</span>
-into the ground to depths varying from 42 to 48 feet. A toothed or
-serrated edge, as in <a href="#fig108">Fig. 113</a>, is sometimes given to the lower edge
-for screw piles which have to cut their way through a hard stratum.</p>
-
-<p>All bolting flanges should be accurately turned and fitted to ensure
-close, parallel surfaces when bolted together.</p>
-
-<p>The joint shown at <strong>A</strong>, <a href="#fig112">Fig. 112</a>, is one the writer has used to a
-large extent for the bolting flanges of cast-iron screw piles and
-cylinders. It is very simple in form, readily coated with white lead
-to ensure a water-tight joint, and as the upper length is practically
-recessed, or let into the lower length, the exact continuity of the
-different castings is secured.</p>
-
-<p>Solid screw piles of wrought-iron or steel, similar to <a href="#fig108">Fig. 114</a>, are
-used for some descriptions of work. These are generally made in long
-lengths, in sizes varying from 4 to 8 inches in diameter, and with
-screw blades of wrought-iron or cast-iron fixed in the most secure
-manner to resist the strain produced when screwing into the ground.
-The couplings for these solid piles must be very carefully made, all
-contact surfaces truly faced and fitted, bolts turned, and bolt-holes
-drilled.</p>
-
-<p><a href="#fig108">Fig. 115</a> is a sketch of a hollow cylindrical water-jet pile, which has
-been used successfully in cases of light sand. The lower end of the
-pile is made externally in the form of a solid disc, terminating in a
-conical point, having an aperture in the centre to correspond to the
-water-jet. To the top of the pile is secured a tight-fitting cover
-through which a tube passes from a force pump. Water at high pressure
-is pumped into the tube, and as it forces its way out through the
-conical point the sand is stirred up and loosened, and thus allows the
-pile to descend. When the pile has been lowered to a sufficient depth
-the pumps and tube are removed, and the sand settles down into its
-former compact condition.</p>
-
-<p>Great care must be used with the first two or three lengths of any
-screw pile to ensure the pile taking a correct or true vertical
-position. Each series of screw piles should be properly braced
-together to obtain stability under moving loads.</p>
-
-<div class="figcenter">
- <a name="fig116"></a>
- <img src="images/i117.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 116"
- title="Figure 116"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig117"></a>
- <img src="images/i118.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 117"
- title="Figure 117"
- />
-</div>
-
-<p>Hollow cylinders of cast-iron, wrought-iron, or steel form most
-efficient foundations or piers for large bridges over soft ground or
-fresh water of considerable depth. Made open at the bottom, and
-constructed of complete rings, or, if of large diameter, of rings
-built up in segments and securely attached together
-<!--127.png--><!--128.png--><!--129.png--><a name="Page_119" id="Page_119"></a><span class="pagenum">[Pg 119]</span>
-with water-tight
-joints, the cylinder is placed in its proper position on the ground or
-lowered into the water preparatory to sinking. The lower length is
-made with a sharp cutting edge to facilitate penetration. By
-excavating and removing the material round the cutting edge and base
-inside the lower length, the cylinder descends gradually either from
-its own weight or by assisted weights, and length after length is
-added until it is sunk to the depth required. The excavated material
-is filled into buckets and hoisted to the surface by a winch fixed on
-the top length. When sinking in water the working top of the cylinder
-is always kept at a suitable height above the water for convenience in
-removal of the earth or clay from the interior to barges or gangways
-alongside.</p>
-
-<p>Some strata are more favourable for cylinder sinking than others.
-Material of a strong clayey nature admits but a small amount of water
-into the excavation, and a moderate-sized pump will keep the working
-fairly dry until considerable depth has been reached. Some other
-materials are so open that the water cannot be kept down with ordinary
-pumps, and the cylinders can then only be lowered by the pneumatic
-process. This process has been carried out in two methods, one of them
-on the <em>vacuum</em> principle, and the other by air pressure, or, as it is
-termed, the <em>plenum</em> system. With the former method the cylinder is
-placed in position, and an air-tight cap, through which a pipe passes,
-is secured on the top. Powerful air-pumps are then set to work, and
-the partial vacuum thus created in the interior causes the material
-round the cutting edge and base to be loosened and drawn into the
-cylinder, the cylinder at the same time going down or sinking by its
-own weight, or assisted, if necessary, by added weights. The cap is
-then taken off, and the material removed from the interior, the
-operation of exhausting and emptying the interior being repeated until
-the cylinder is sunk to its proper depth. This method has been found
-to work well in strata which contained a large proportion of clay to
-assist in excluding the air and water, but was not nearly so
-successful when applied to material containing stones and large
-boulders.</p>
-
-<p>The <em>plenum</em> process is based on the principle of the diving-bell, the
-water being prevented from entering at the bottom by keeping the
-cylinder full of compressed air. An air-chamber, or <em>air-lock</em>, with
-perfectly air-tight joints, is securely fixed to the
-<!--130.png--><a name="Page_120" id="Page_120"></a><span class="pagenum">[Pg 120]</span>
-top or upper
-working length of the cylinder, and no access can be obtained to the
-interior of the cylinder without passing through this air-lock, which
-has one lower door or valve opening into the cylinder, and an upper
-door opening out into the open air. Temporary inside staging is formed
-by putting planks across from flange to flange, and placing short
-ladders on these landings for the use of workmen descending or
-ascending. The excavated material is hoisted by a winch, generally
-placed on the landing just under the air-lock. The air-pump is placed
-in some convenient position outside, near at hand, the pressure-pipe
-passing through the air-lock into the interior of the cylinder. Air is
-forced into the cylinder to a pressure sufficient to drive out and
-keep out the water from the interior, and allow the workmen free
-access for excavating the material round the cutting edge and base of
-cylinder. The amount of pressure required will depend upon the depth
-of the working below the level of the water alongside. Men accustomed
-to the process can work without much inconvenience under a pressure of
-20 to 22 pounds per square inch, equal to a depth of 45 to 50 feet;
-but when the pressure exceeds 25 pounds, the duty becomes very trying,
-and is attended with considerable risk. Instances are recorded of men
-working at depths of 105 and 110 feet, necessitating a pressure of
-over 45 pounds per square inch; but it is very questionable whether
-the men exposed to such a severe ordeal were not permanently affected,
-if some of them did not actually succumb.</p>
-
-<p>It will sometimes occur that, after sinking through soft porous strata
-to a considerable depth, a layer of clayey material is penetrated
-sufficiently retentive to keep out the water and permit of the removal
-of the air-lock and the completion of the sinking as an open-top
-cylinder.</p>
-
-<p>When working on the <em>plenum</em> system everything must pass through the
-air-lock, both materials and men. The excavated material is hoisted up
-to the level of the air-lock, the upper and lower doors of which must
-be closed, and the pressure inside the air-lock brought to the same as
-that inside the cylinder by means of a regulating valve. The lower
-door is then opened to admit the excavated material, and then closed
-again to cut off all communication with the interior of the cylinder.
-The upper door is then opened, and the material hoisted out into the
-open air. The same process has to be adopted for the egress of the
-workmen,
-<!--131.png--><a name="Page_121" id="Page_121"></a><span class="pagenum">[Pg 121]</span>
-and the reverse arrangement for the ingress of men and
-materials. The shape and dimensions of the air-lock may be varied
-according to circumstances, but the principle will remain the same.</p>
-
-<p>When the cylinder has been lowered to what is considered a sufficient
-depth, it is usually loaded with a certain amount of dead weight in
-the shape of old iron or other convenient material, and allowed to
-remain loaded for some days to ascertain if it will sink any further.
-Should this test be found satisfactory, the dead weight is removed,
-and the interior of the cylinder pumped dry and carefully filled with
-good cement concrete.</p>
-
-<p>Cylinders for foundations are generally made circular in section, that
-form being the most convenient for turning and facing the
-flange-joints. They can, however, be made oval in section, or of any
-section that may be found most suitable for the work required.<a href="#fig116"> Figs.
-116</a> and <a href="#fig117">117</a> give the particulars of a double-line railway bridge
-carried on cylinder piers across a river. The detail sketches explain
-the form of cutting edge, flange joint, and method of bracing. This
-bridge is one that was reconstructed and widened from a single-line to
-a double-line bridge. Traffic was carried over on one line while the
-second line was being erected, hence the reason why one strong central
-girder was not adopted.</p>
-
-<p>Cylinders of 7 feet diameter and upwards are sometimes filled with
-concrete in the lower portion, on which is built either a circular
-lining or a solid mass of masonry or brickwork up to the level of the
-girder-blocks. In some cases the cylinders proper, together with their
-concrete filling, terminate a little above the water-level, and upon
-these foundations are erected strong cast-iron columns, plain or
-ornamented in design, to carry the girders and roadway. The cylinder
-itself is generally considered merely as a casing or medium for
-obtaining a foundation, the weight of the superstructure being carried
-on the internal filling or lining.</p>
-
-<p>Caissons constructed of plates of wrought-iron or steel are much used
-for the foundations of large piers in deep water. Practically they may
-be considered as cylinders on a large scale, with the difference that
-whereas cylinders are generally continued up to the under side of the
-girders of the superstructure, caissons are only carried up to a short
-distance above the water-level. A caisson forms a strong water-tight
-iron cofferdam, from
-<!--132.png--><a name="Page_122" id="Page_122"></a><span class="pagenum">[Pg 122]</span>
-which the water can be excluded, and a masonry or
-brickwork pier constructed inside. It may be made all in one piece to
-correspond to the form of the pier, or in separate pieces to form one
-whole, each being sunk independent of the other, and connected
-together afterwards. Being built up of plates cut to the proper size
-and shape, it is a very simple matter to rivet on additional tiers of
-plates as the caisson is lowered deeper and deeper into the bed of the
-river. The lower length is made with a cutting edge to penetrate the
-ground; the exterior is made without any projection larger than the
-rivet heads, and the interior is strengthened with <strong>T</strong>-irons or double
-<strong>L</strong>-irons at the joints, and strong cross-bracing to resist the
-pressure of the water. About 7 or 8 feet above the cutting edge a
-strongly framed iron floor is riveted to the vertical sides, and
-strengthened by plate-iron under-brackets placed at short distances.
-The excavators work in the space below the floor, and the excavated
-material is passed up through openings formed in the floor at
-convenient points to suit the working. The methods of lowering a
-caisson are the same as for lowering a cylinder. If the pneumatic
-system has to be adopted, then two or more air-tight tubes of liberal
-dimensions (say 5 to 8 feet diameter), according to the size of the
-caisson, must be attached to the floor, and on the top of each of
-these tubes air-locks must be secured for the removal of men and
-materials. The masonry or brickwork of the pier is built upon the iron
-floor, and a portion of this building work is usually carried on
-during the sinking of the caisson to obtain weight to assist in the
-lowering. When down to the proper depth, the space below the floor is
-properly cleared of <i lang="fr">débris</i> and water, and then carefully filled in
-with cement concrete.</p>
-
-<p>Some caissons are made with vertical sides throughout their entire
-height; others have an outward taper for 15 or 20 feet on the lower
-end. The former are not only simpler in construction, but are more
-easily kept in a vertical position during the sinking. Caissons are
-usually put together in some convenient place near the edge of the
-water, and then conveyed on pontoons to the sites of the piers. Great
-care is required in lowering them into position in the bed of the
-river, and guide-piles, guy-chains, and other appliances are
-frequently necessary to keep them vertical during the sinking.</p>
-
-<p>The form, dimensions, thickness of plates, cross-bracing, and general
-arrangement will depend upon the size and depth of the
-<!--133.png--><a name="Page_123" id="Page_123"></a><span class="pagenum">[Pg 123]</span>
-pier to be
-constructed. Caissons for heavy work on difficult or treacherous
-ground require great care, not only in their construction, but also in
-placing them in exact position, and in sinking them correctly to their
-proper depth. A tilted caisson is a most difficult subject to handle,
-and entails heavy expenditure to restore it to a true vertical
-position. By making careful borings, the engineer can ascertain very
-closely the depth to which the caisson will have to be lowered to
-obtain a good firm foundation. With this information the caisson can
-be so constructed that the upper portion, termed the temporary
-caisson, commencing a few feet above the bed of the river, can be
-detached, and removed at the completion of the work from the lower or
-permanent portion sunk below the ground line.</p>
-
-<p><a href="#fig118">Fig. 118</a> gives sketches of a wrought-iron plate-caisson applied to a
-deep-water river pier, and lowered to its full depth by the pneumatic
-process; dotted lines show the air-tubes through which the excavated
-material is hoisted and emptied into barges alongside.</p>
-
-<p>Many large and important pier foundations have been constructed on the
-system of brick cylinders or wells, particularly in India, where the
-foundations for large river viaducts have to be carried down to great
-depths through thick deposits of soft material. These wells are built
-upon <strong>V</strong>-shaped curbs to facilitate the penetration when sinking. <a href="#fig119">Fig.
-119</a> is a section of a well with a wrought-iron curb, and <a href="#fig119">Fig. 120</a> is a
-similar well with a wooden curb. The wrought-iron curb is made in
-segments for convenience of transport, the pieces forming the complete
-ring being bolted or riveted together at the site of the foundations.
-The wooden curb is composed of several thick layers of hard wood
-planking cut to the proper shape, and laid with broken joints, the
-whole being bound together with suitable bolts and spikes. In some
-cases the lower or cutting edge of the wooden curb is strengthened or
-protected by a sheathing of wrought-iron plates.</p>
-
-<div class="figcenter">
- <a name="fig118"></a>
- <img src="images/i124.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 118"
- title="Figure 118"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig119"></a>
- <img src="images/i125.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 119 through 123"
- title="Figures 119 through 123"
- />
-</div>
-
-<p>Well foundations are usually put in when the rivers are at their
-lowest, and reduced to a few small channels in the great width of
-dried-up river bed. This condition enables the greater portion of the
-curbs to be conveniently and accurately placed in position on dry
-ground, or on ground which, although soft and muddy, is not covered
-with water. Should the site of one of the wells occur in one of the
-small channels, the stream can be
-<!--134.png--><!--135.png--><!--136.png--><a name="Page_126" id="Page_126"></a><span class="pagenum">[Pg 126]</span>
-diverted to one side, and a small
-artificial island made to receive the curb above water-level. When a
-curb is fairly fixed in position, the work of building the brick well
-can be commenced. With the wrought-iron curb the triangular cavity
-between the vertical plate and sloping plate must be filled with
-concrete to form a level base for the first course of brickwork. The
-wooden curb being composed of horizontal layers of timber, is ready to
-receive the brickwork without further preparation. To strengthen and
-keep the brickwork firmly tied together, strong wrought-iron vertical
-tie-rods, 1¼ or 1½ inch in diameter, are generally built into the
-work&mdash;as shown in the sketches&mdash;at distances about four feet apart.
-The lower end of the bottom tier of tie-rods is secured to the curb,
-and the upper end passed through a strong wrought-iron plate-ring,
-which is continuous all round the brickwork. A long deep nut is
-screwed down over the top or screwed end of tie-rod until the
-plate-ring is down tight on the brickwork. The tightening nuts are
-made sufficiently deep to receive the lower ends of a second series of
-vertical tie-rods, which in like manner pass through another
-wrought-iron plate-ring on the next section of brick well, and the
-same arrangement is continued for the full height of the well. The
-lengths of the tie-rods will depend upon the lengths of the section of
-brickwork to be built at a time, and may vary from 10 to 15 feet.</p>
-
-<p>As the work of building proceeds the curb and brick well will sink
-gradually into the ground, and down to a certain depth, varying
-according to the material of the river bed, the weight of the brick
-well itself will effect the penetration and lowering. Beyond this
-depth the lowering must be done by scooping or dredging the material
-from the inside of the well, and placing heavy weights of old railway
-iron or other convenient masses on the top. When one section or length
-of well has been sunk down, then another set of tie-rods are inserted
-into the deep nuts, and another section of brickwork commenced. The
-operation of lowering is rather tedious, as all the weights have to be
-hoisted up on to the top of the length in hand, and piled so as to
-leave space for lifting out the material dredged from the interior;
-and then, when the length has been lowered, all the weights must be
-removed before the brickwork can be resumed on another length. Where
-the river bed consists of soft material, the excavation inside the
-well can generally be
-<!--137.png--><a name="Page_127" id="Page_127"></a><span class="pagenum">[Pg 127]</span>
-effected by suitable dredges or scoops worked
-from the surface or top of brickwork. Should trees or other
-obstructive masses be met with embedded in the strata, it will be
-necessary to employ divers to remove them piecemeal out of the way of
-the curb.</p>
-
-<p>When the brick well has been lowered down to the full depth, and is
-thoroughly bedded in a stratum of strong material, the test weights
-should be left on for some time to ascertain if there is any further
-sinking. After all the weights have been removed the bottom of the
-well can be dredged out clean, and the interior filled in with
-concrete to such height as may be considered necessary.</p>
-
-<p>Brick wells must be watched carefully to ensure that they sink down in
-a perfectly vertical position. Any inclination away from the
-perpendicular must be corrected at once by means of guys and struts,
-the same as in sinking iron cylinders. The principal difficulty will
-be with the first 20 or 25 feet.</p>
-
-<p>The diameter of the well will depend upon the weight it has to carry,
-and its height from river bed to under side of girders. The wells may
-be either circular or polygonal in section, and built singly or in
-pairs, as shown in sketches (<a href="#fig119">Fig. 121</a>).</p>
-
-<p>Many piers and abutments of bridges in shallow or moderately deep
-water are built by means of coffer-dams of timber and clay puddle. The
-coffer-dam forms a water-tight wall round the site of the foundation,
-from which the water is pumped out, and the excavation carried down to
-the depth required. In very shallow water it is sometimes sufficient
-to drive only a single row of piles, and form a bank of good clay
-puddle on the outside, as shown in <a href="#fig119">Fig. 122</a>. In deep water it is
-necessary to drive a double row of piles, 3 or 4 or more feet apart,
-and fill in the space between with clay puddle, as shown in <a href="#fig119">Fig. 123</a>.
-The piles for coffer-dam work should be carefully selected, of good
-timber straight, and correctly sawn on the contact faces. Guide-piles
-are first driven in proper line and position round the intended
-foundation. To these strong horizontal double waling pieces are
-securely bolted, one on each side of the guide-pile, one pair near the
-top, and the other pair as low down as can be placed. The sheeting
-piles, which are lowered down between the horizontal waling or guiding
-pieces, are driven as close to one another as possible, being assisted
-in doing so by the sheet-pile shoe, shown on <a href="#fig108">Fig. 124</a>, which is made
-not with a point like
-<!--138.png--><a name="Page_128" id="Page_128"></a><span class="pagenum">[Pg 128]</span>
-an ordinary pile shoe (<a href="#fig108">Fig. 125</a>), but with a
-cutting edge slightly inclined, so that in driving the tendency of the
-pile is to drift towards the pile previously driven. Sometimes the
-outer row of piles consists of whole balks, and the inner row of half
-balks; the size of the piles must, however, be regulated by the depth
-and current of the water. When both rows of piles have been completed,
-the space between should be dredged out, and then filled with
-carefully prepared clay puddle. To enable the puddle to adapt itself
-thoroughly to the wooden sides, it is desirable to remove the inside
-walings after all the piles are driven, as any internal projections
-interfere with the proper punning and settling of the puddle. The
-swelling of the puddled clay has a tendency to force apart the two
-rows of piles, and to counteract this as much as possible, iron
-tie-rods should be passed through from side to side every few feet,
-and screwed up against large washers placed on the outside of the
-outer walings. Strong struts or cross-bracing of timber must be placed
-from side to side inside the coffer-dam to resist the pressure of the
-water in the river. This cross-bracing can be removed gradually as the
-work of building progresses upwards, and be replaced with short struts
-wedged in against the sides of the finished courses.</p>
-
-<p>In cases where the ground is soft, and when it is not considered
-prudent to excavate the foundations deeper for fear of disturbing the
-stability of the coffer-dam piles, rows of large, square bearing-piles
-may be driven in the floor of the foundation, as shown in <a href="#fig108">Fig. 111</a>.
-The tops of these bearing-piles must all be sawn off to the same
-level, and a platform of strong double planking securely fixed to the
-piles to receive the foundation course of concrete, masonry, or
-brickwork. The spaces around the tops of the piles and the under side
-of the timber platform should be filled in with good cement concrete.</p>
-
-<p>The interior of the coffer-dam is kept dry by constant pumping, either
-by hand pumps or steam pumps, according to the volume of water finding
-its way into the foundations. When the finished pier or abutment has
-been carried up above the river water-level, the coffer-dam is no
-longer required, and may be removed. Sometimes, to save the timber,
-the piles are drawn by means of strong tackle fitted up for the
-purpose; but in doing this there is considerable risk of disturbance
-to the foundations, and it is better to leave the piles in the ground
-<!--139.png--><a name="Page_129" id="Page_129"></a><span class="pagenum">[Pg 129]</span>
-and employ divers to cut off the tops a little above the bed of the
-river.</p>
-
-<p>In preparing the design for a large foundation it is absolutely
-necessary to first ascertain by careful borings the description of
-material upon which that foundation must be placed, so as to
-proportion the area of bearing surface to the weight to be sustained.
-Some materials will naturally carry more weight than others, and
-although the engineer cannot always select the material he would
-prefer, he can, however, control the superficial area of the
-foundations. Much valuable information has been obtained both from
-experiments and from comparisons of actual practice, and the following
-memoranda may be useful for reference, as indicating the pressures per
-superficial foot which may be safely put on various <span style="white-space:nowrap;">materials:&mdash;</span></p>
-
-<table summary="pressures per superficial foot">
-<tr><td class="left">Moderately stiff clay</td><td class="maxwide right">2½ tons.</td>
-</tr>
-<tr><td class="left">Chalk</td><td class="right">4&emsp;”&emsp;</td>
-</tr>
-<tr><td class="left">Solid blue clay</td><td class="right">5&emsp;”&emsp;</td>
-</tr>
-<tr><td class="left">Compact gravel and close sand</td><td class="right">6&emsp;”&emsp;</td>
-</tr>
-<tr><td class="left">Solid rock</td><td class="right">12&emsp;”&emsp;</td>
-</tr>
-</table>
-
-<p>Doubtless the above weights have been exceeded in many cases, but it
-is better to be on the safe side, and leave a good margin for
-stability.</p>
-
-<p>Large subaqueous foundations for heavy piers and abutments are costly
-and tedious, and especially so when the pneumatic process has to be
-adopted. Special appliances and well-trained, experienced workmen are
-requisite, and if all the men and materials have to pass through the
-air-locks, the progress of the work must necessarily be slow. When the
-foundations have been completed up to the level of the water, the
-construction can be pushed on more rapidly, as the work of
-scaffolding, hoisting, and building, can all be carried on in the open
-air.</p>
-
-<p>Amongst the very many types of arch-work and girder-work adopted for
-railway purposes, the following examples from actual practice may be
-useful for <span style="white-space:nowrap;">reference:&mdash;</span></p>
-
-<div class="figcenter">
- <a name="fig126"></a>
- <img src="images/i130.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 126 and 127"
- title="Figures 126 and 127"
- />
-</div>
-
-<p><a href="#fig126">Fig. 126</a> represents small 24-foot span, low viaduct arching suitable
-for a line passing through towns or villages, where ground is valuable
-and the area to be covered must be kept as small as possible. The
-arches may be utilized for stables, stores, or roads of communication
-between the lands and properties intersected by the railway. The
-segmental form gives a better headway underneath than the
-semicircular, besides containing less material in the arching proper,
-and requiring a smaller
-<!--140.png--><!--141.png--><a name="Page_131" id="Page_131"></a><span class="pagenum">[Pg 131]</span>
-amount of centering. Every precaution should
-be taken to prevent water percolating through any portion of the
-arching, or haunching, and a thick layer of good asphalte should be
-placed over the entire upper surface, and carried well up the lower
-portion of the parapet walls, as shown on the sketch. The cast-iron
-pipes with rose heads form a very efficient means of taking away the
-rain-water which filters through the ballast and filling. The pipes
-should be carried down in chases, or recesses, built in the fronts of
-the piers, to protect them as much as possible from injury in the
-yards below. Rose heads, pierced with holes, and surrounded with small
-stones hand-laid, serve well to conduct the water into the pipes.
-Where the arching is of considerable length, recesses or refuges for
-the platelayers may be obtained by substituting a short length of
-cast-iron-plate parapet, instead of the stone or brick parapet, over
-some of the piers, as indicated in the sketch.</p>
-
-<p><a href="#fig126">Fig. 127</a> shows a similar description of arching for spans of 30 feet.
-The above two examples represent plain substantial work, but if
-circumstances warrant more external finish, this can readily be added
-without interfering with the general arrangement. In a similar manner,
-if considered preferable, the arches may be made semicircular or
-elliptical.</p>
-
-<p>In the sketches shown of the arched over-line and under-line bridges,
-the arching and coping of parapets are in brick, and the remainder of
-the work in stone. In very many cases brick will be found cheaper and
-more expeditious for arching than stone, unless the quarries turn out
-stone in blocks which can be conveniently trimmed for arching. All
-bricks used for arch-work should be hard and well burnt, and special
-care should be taken in the selection of those to form the under-side
-course, which will be exposed to the atmosphere. For moderate spans
-arches have been successfully constructed of concrete. For this
-description of work the materials should be carefully gauged and mixed
-together, and the finished work should be allowed to stand some time
-on the centres to allow the concrete to become thoroughly set.</p>
-
-<div class="figcenter">
- <a name="fig131"></a>
- <img src="images/i132.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 131"
- title="Figure 131"
- />
-</div>
-
-<p>In <a href="#fig102">Fig. 102</a>, the cutting being deep, almost up to the level of the
-public road, the foundations of the wing walls are built in steps,
-resulting in a minimum of masonry below the finished ground line.
-Where the cutting is shallow, and the public road has to be brought up
-to the bridge on an embanked
-<!--142.png--><!--143.png--><a name="Page_133" id="Page_133"></a><span class="pagenum">[Pg 133]</span>
-approach, the greater portion of the wing
-walls will have to be built up from the solid or original ground, and
-there will be a large amount of masonry below the finished ground
-line, as indicated in <a href="#fig102">Fig. 128</a>.</p>
-
-<p>In some cases of over-line bridges it is necessary to curve the wing
-walls to correspond to the road which turns off to the right or left
-after crossing the railway, as shown in <a href="#fig102">Fig. 129</a>; or the wing walls
-may have to form two separate curves where the road branches off in
-two directions after leaving the bridge, as shown in <a href="#fig102">Fig. 130</a>.</p>
-
-<p><a href="#fig131">Fig. 131</a> shows plan, elevation, and cross-section of an under-line
-arch bridge, considerably on the skew, carrying a railway over a
-river. The wing walls are curved, and very similar in type to some of
-those in preceding examples. The river bed and ground alongside being
-of solid rock, good foundations were obtained at a very moderate cost.</p>
-
-<p>On many railways constructed in the beginning as single lines only,
-the over-line bridges have been built for double line. The additional
-cost in the outset has been small, compared with the great expenditure
-which would be incurred afterwards in reconstructing the bridges to
-suit a double line.</p>
-
-<p>The general arrangement of abutments and wing walls shown in the
-foregoing examples will apply to similar classes of bridges where
-girder-work is adopted instead of arching.</p>
-
-<p>There are many ways of forming the floor or deck of a girder bridge
-intended to carry a railway over a road or stream. In some cases it
-will be imperative to have a thoroughly water-tight floor to prevent
-rain-water percolating through to the roadway below; while in others,
-such as bridges over streams, and secondary roads, this special
-provision will not be necessary, and a lighter and more economical
-floorway can be adopted. A strong wrought-iron or steel-plate
-flooring, with its corresponding filling and ballasting, means not
-only so much additional cost in the flooring proper, but also so much
-additional dead weight to be carried by the main girders.</p>
-
-<div class="figcenter">
- <a name="fig132"></a>
- <img src="images/i134.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 132, 133, 134, 135, 136, 141"
- title="Figures 132, 133, 134, 135, 136, 141"
- />
-</div>
-
-<p><a href="#fig132">Fig. 132</a> is a sketch of rolled joist-iron <strong>I</strong>-girders and timber floor
-frequently adopted for small farm roads and cattle creeps of 10 or 12
-feet span. A beam of timber is fitted in between the two rolled
-joist-irons, and the three pieces securely fastened together with
-strong iron bolts placed about 3 feet apart. These small compound
-girders rest on bearing-plates of wrought or cast
-<!--144.png--><!--145.png--><a name="Page_135" id="Page_135"></a><span class="pagenum">[Pg 135]</span>
-iron, and are held
-together and to gauge by tie-rods, as shown. The rails are spiked or
-bolted down on to the timber beams, and the flooring formed of strong
-planking.</p>
-
-<p><a href="#fig132">Fig. 133</a> shows an arrangement of plate girders for a 16-foot opening
-over a stream. The girders are placed immediately under the rails, and
-are tied together by plate-iron cross-bracing the same depth as the
-main girders. The flooring consists of 4-inch planking laid with
-¾-inch spaces, on which are laid longitudinal rail-bearers 14 inches
-wide by 7 inches thick.</p>
-
-<p><a href="#fig132">Fig. 134</a> is a sketch of a somewhat similar arrangement for a
-lattice-girder bridge, 45 feet span, carrying a single line of railway
-over a river. The main girders are tied together by lattice-work
-cross-bracing. The floorway consists of 5-inch planking, laid with
-¾-inch spaces, on which is placed the 14 feet by 7 feet longitudinal
-rail-bearers. Plate-iron outside brackets are riveted to the main
-girders to carry the ends of the planking and light tube-iron parapet.</p>
-
-<p><a href="#fig132">Fig. 135</a> illustrates an example of trough girders, constructed to
-carry a double-line railway over a country road 25 feet wide, where
-the space from under side of girder to rail-level is small. The
-girders are constructed in pairs, with short, shallow cross-girders at
-3 feet 6 inch centres, riveted in between them to carry longitudinal
-timbers on which the rails are laid. Bottom plates, 5/8 inch thick,
-unite the two girders for the length of their bearing on the
-abutments, and a similar plate, 9 inches wide, unites them at the
-centre; the remainder of the span is left open to prevent the lodgment
-of rain-water. Three strong tie-rods are placed to keep the girders to
-gauge. Curved wrought-iron ballast-plates are used between the
-running-rails, and plank flooring forms the rest of the covering.</p>
-
-<div class="figcenter">
- <a name="fig137"></a>
- <img src="images/i136.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 137"
- title="Figure 137"
- />
-</div>
-
-<p><a href="#fig132">Fig. 136</a> is a sketch of a plate-girder bridge over a country road 28
-feet wide, with the load carried on the lower flange of girder. Three
-main girders carry the double line of railway, the centre one having
-double the strength of each of the outside girders. On the top of the
-cross-girders, strong angle irons are riveted to serve as guides and
-supports for the longitudinal timbers which carry the rails. Every
-third cross-girder has raised ends to give increased lateral stability
-to the main girders. A close cast-iron plate parapet forms a screen to
-the roadway. Wrought-iron ballast-plates are used between the
-running-rails, and the remainder of the flooring is of timber.</p>
-
-<p><!--146.png--><!--147.png--><a name="Page_137" id="Page_137"></a><span class="pagenum">[Pg 137]</span>
-<a href="#fig137">Fig. 137</a> gives the particulars of one 60-foot span of a viaduct
-carrying a double line of railway over tidal water. The main girders
-are placed one under each line of rails, and all the four are strongly
-tied together by lattice-work bracing the full depth of the girders.
-The outside footpaths for the platelayers are carried on strong
-brackets, riveted to the main girders. Longitudinal timbers, coped
-with angle iron, are placed as outside guards, alongside each rail,
-for the full length of the viaduct. Wrought-iron ballast-plates are
-placed between the running-rails. The remainder of the footways
-consist of timber planking, laid with half-inch spaces, and covered
-with a layer of small pebbles as a protection against fire.</p>
-
-<p><a href="#fig138">Fig. 138</a> shows a very similar arrangement in a viaduct carrying a
-single line of railway across a river. The two main lattice
-girders&mdash;66 feet span&mdash;are placed at 9-foot centres, to obtain greater
-stability. The cross-girders are extended to carry the outside
-footpaths and handrailing. Outside guards are placed alongside each
-rail as in the preceding example. Wrought-iron ballast-plates are
-fixed all along between the running-rails, and timber planking used
-for the rest of the floorway.</p>
-
-<p><a href="#fig138">Fig. 139</a> gives cross-section of a lattice-girder bridge, 82 feet span,
-carrying a single line of railway over a river, with the load carried
-on the lower flange. The cross-girders are placed at 4 feet 3 inch
-centres. Wrought-iron ballast-plates compose the floorway between the
-rails, and timber planking covers the rest of the bridge. Plate
-diaphragms, or stiffeners, of the form shown at <strong>A</strong>, <strong>A</strong>, <strong>A</strong>, <strong>A</strong>,
-are riveted to the main girders at five places in their length.</p>
-
-<p><a href="#fig140">Fig. 140</a> shows cross-section of a lattice-girder bridge of 200 feet
-span, carrying a single line of railway over a river, the load being
-placed on the lower flange. The floorway consists of plate-iron
-cross-girders, spaced at 4-foot centres, on which are placed the
-longitudinal rail-bearers and planking, the latter being covered with
-a layer of clean pebbles for the width between the running-rails. As
-the depth of the main girders was sufficient to admit of overhead
-bracing, strong plate-iron diaphragms, of the form shown on the
-sketch, were riveted to the main girders at every 50 feet. These
-diaphragms thoroughly brace the two girders together, and effectually
-prevent any tendency to side-canting, at the same time imparting an
-effective appearance to the bridge.</p>
-
-<div class="figcenter">
-<!--148.png--><a name="Page_138" id="Page_138"></a><span class="pagenum">[Pg 138]</span>
- <a name="fig138"></a>
- <img src="images/i138.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 138, 139, 143"
- title="Figures 138, 139, 143"
- />
-</div>
-
-<p><!--149.png--><a name="Page_139" id="Page_139"></a><span class="pagenum">[Pg 139]</span>
-<a href="#fig132">Fig. 141</a> shows cross-section of a plate-girder bridge, of 36 feet
-span, carrying six lines of way across a street. Strong plated
-cross-girder bracing, at 4 feet 8¼ inch centres, is riveted to the
-main girders, and the top is covered with old Barlow rails, 12 inches
-wide, and weighing 90 lbs. per lineal yard. A layer of asphalte, about
-1½ inches thick, is carefully laid all over the upper surface of these
-rails to make a thoroughly water-tight floor. Clean gravel is placed
-on the top, on which are laid the sleepers and rails of the permanent
-way. Rain-water passes through the gravel into the hollows of the
-Barlow rails, and finds its way into suitable drains provided at each
-abutment. This arrangement not only prevents the falling of drip-water
-into the street below, but permits of the alterations of the lines of
-way, or putting in of cross-over roads on the surface above. The
-outside main girders are made deeper, and are surmounted by close
-cast-iron parapets.</p>
-
-<p><a href="#fig142">Fig. 142</a> gives the particulars of a three-span plate-girder bridge,
-constructed to carry a double line of railway over two other railways
-and a canal, the load being placed on the lower flange. Two main
-girders are used for each line of way. Strong plated cross-girders are
-placed at 5 feet 3 inch centres, and on the top of these is laid a
-flooring of old Barlow rails, terminating at the sides with sloping
-wing-plates riveted to the cross-girders and main girders, the entire
-surface being covered with an inch and a half layer of asphalte. Good
-gravel ballast is placed on the top, on which are laid the sleepers
-and rails. One central main girder of sufficient strength would have
-been as efficient as the two central girders, but there was a
-practical difficulty which prevented its adoption. The new girder-work
-was built to replace an old structure of peculiar arrangement, and to
-keep the traffic going on one line there was no alternative but to
-make each line of way complete in itself.</p>
-
-<div class="figcenter">
- <a name="fig140"></a>
- <img src="images/i140.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 140 and 144"
- title="Figures 140 and 144"
- />
-</div>
-
-<p><a href="#fig138">Fig. 143</a> illustrates an example of jack arches in concrete built
-between strong plate-girders. The span of the girders was only 16
-feet, but the opening or roadway was of considerable length, and
-passed under a portion of a busy station yard. The girders are placed
-at 6-foot centres, and tied together in pairs by 1¼-inch tie-rods,
-three to the span, spaces of 6 inches in plan being allowed between
-each set of the rods. The concrete was curved up to the top plate of
-the girder, as shown, and the entire surface covered with a thick
-layer of asphalte, on which were
-<!--150.png--><!--151.png--><a name="Page_141" id="Page_141"></a><span class="pagenum">[Pg 141]</span>
-placed the ballast and permanent way.
-Brickwork might have been used for the jack-arching, but concrete was
-considered more convenient.</p>
-
-<p><a href="#fig140">Fig. 144</a> shows the cross-section of a truss-girder bridge of 123 feet
-span, carrying a double line of railway over a wide thoroughfare, the
-load being placed on the lower flange. There are two main girders,
-each 12 feet 6 inches deep in the centre, and 8 feet deep at the ends.
-Plate cross-girders are placed at 4 feet 6 inch centres, on which is
-riveted longitudinal plate-iron troughing, extending across the bridge
-and terminating at the sides with wing-plates, as shown. The entire
-floor is covered with a thick layer of asphalte previous to filling in
-with ballast to receive the permanent way. Plate stiffeners are
-adopted in this bridge very similar to those in <a href="#fig138">Fig. 139</a>.</p>
-
-<p><a href="#fig145">Fig. 145</a> gives plan, elevation, and cross-section of a plate-girder
-bridge of 95 feet span, carrying a double line of railway over a very
-busy street. There are two curved-top main girders, each 10 feet 9
-inches deep in the centre, and 6 feet 7½ inches deep at the ends. The
-arrangement of cross-girders, longitudinal plate-iron troughing, and
-permanent way, is very similar to that in the preceding example, but
-the side wing-plates are carried up higher, and are riveted up to the
-web-plate of main girder, forming continuous stiffeners from end to
-end of the main girders. A light, ornamental, close cast-iron parapet
-is bolted on to the top of the curved, or upper, boom of the main
-girder, the top line of the parapet being carried out parallel to the
-bottom boom of girder. This bridge crosses the street very obliquely,
-and, although cast-iron columns were allowed at the edge of the
-footpaths, the main spans are unavoidably large. When designing the
-above bridge, the writer had to adopt a girder that would form a
-screen, to provide a deck, or floor-way, which would be not only
-water-tight, but also deaden as much as possible the sound or
-vibration of passing trains, and at the same time give some ornamental
-appearance to the girders and parapets. This bridge carries a constant
-service of heavy trains; it is perfectly dry underneath, and is
-remarkably free from noise or vibration.</p>
-
-<div class="figcenter">
- <a name="fig142"></a>
- <img src="images/i142.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 142"
- title="Figure 142"
- />
-</div>
-
-<p><a href="#fig146">Fig. 146</a> shows cross-section of a plate-girder bridge of 40 feet span,
-carrying a double-line railway over a street, in a situation where the
-depth from top of rails to under side of girders had to be made as
-small as possible. Three main girders
-<!--152.png--><!--153.png--><a name="Page_143" id="Page_143"></a><span class="pagenum">[Pg 143]</span>
-were used, the centre one being
-double the strength of each of the outside girders. Instead of
-ordinary cross-girders, transverse plate-iron troughing was adopted,
-very similar in section to the longitudinal iron troughing in <a href="#fig145">Fig.
-145</a>, but stronger. The troughing rested on the angle iron of bottom
-flange of main girder, and was riveted to the vertical web-plates of
-main girders, shallow additional vertical plates being inserted
-alongside web-plates to prevent any drip-water or moisture coming in
-contact with the main web-plates. The entire surface of the troughing
-was well covered with asphalte before filling the hollows with gravel
-ballast. An ordinary transverse wooden sleeper was placed in each
-hollow, and on these sleepers the rails were secured as shown. In this
-case&mdash;as in others of transverse troughing&mdash;the rain-water had to be
-conveyed away from the hollow of each trough by a separate outlet into
-longitudinal gutters shown at <strong>A</strong>, <strong>B</strong>, and continued on to the
-abutments.</p>
-
-<p>Transverse troughing is always more troublesome than longitudinal
-troughing, as both ends of each trough must be effectually closed to
-prevent the drainage water leaking out on to the web-plates, or angles
-of the main girders. With longitudinal troughing the water is readily
-carried away from each hollow, to cross drains constructed at the
-piers, or abutments.</p>
-
-<p><a href="#fig146">Fig. 147</a> shows cross-section of a truss-girder bridge, 120 feet span,
-carrying a single line of railway over a river. The cross-girders are
-placed at 10-foot centres to correspond to the vertical members of the
-main truss-girder. Longitudinal plate-iron rail-girders are riveted in
-between the cross-girders, and the entire floor is covered with curved
-wrought-iron ballast plates, as shown. The rails are carried on
-longitudinal timbers, which are bolted on to the rail-girders. Angle
-iron brackets, riveted on the top of the cross-girders, keep the rail
-timbers in position and gauge.</p>
-
-<div class="figcenter">
- <a name="fig145"></a>
- <img src="images/i144.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 145"
- title="Figure 145"
- />
-</div>
-
-<p>In each of the above examples, where longitudinal rail timbers are
-adopted, flange rails are shown, as many engineers prefer to have a
-continuous bearing for the rails on bridges, in case of rail fracture.
-There is nothing, however, to prevent the chair road being laid on
-longitudinal timbers, and for this purpose the writer has used chairs
-of the ordinary pattern, specially cast with side lugs to grip the
-timber, as shown in
-<!--154.png--><!--155.png--><a name="Page_145" id="Page_145"></a><span class="pagenum">[Pg 145]</span>
-<a href="#fig146">Fig. 148</a>. Chairs of this form have a very firm
-hold on the longitudinal timber, and the side lugs check any tendency
-of the splitting or opening of the wood when putting in the spikes or
-screw bolts.</p>
-
-<p><a href="#fig149">Fig. 149</a> shows cross-section of a plate-girder over-line bridge, 32
-feet span, carrying a private road, 12 feet wide, over a double-line
-railway. The road traffic being small, the floorway was constructed of
-creosoted planking carried on rolled I-iron cross-girders placed at 3
-feet 8 inch centres, and riveted to the main girders. The horse-tread
-track was provided with a second layer of planking, laid transversely,
-to take up the wear, cross battens, 4 inches by 2 inches, being placed
-at 12-inch centres, and sand spread between to give good foothold. A
-light lattice-work parapet was bolted on to the top of the main
-girders.</p>
-
-<p><a href="#fig149">Fig. 150</a> gives cross-section of a plate-girder over-line bridge, 30
-feet span, carrying a private road, 20 feet wide, over a double-line
-railway. The main girders are tied together by lattice-work bracing,
-spaced at 7-foot centres. Curved wrought-iron plates are laid across
-from girder to girder, and butt against a narrow horizontal plate,
-which forms part of the upper boom. The curved plates are riveted on
-to the top of girder, and form a continuous iron floor, or deck, from
-side to side of the bridge. Upon this iron floor is laid an ordinary
-asphalte roadway. The outside girders are made deeper, and carry an
-ornamental cast-iron parapet. In some bridges of a similar
-construction, the roadway is formed of creosoted wooden block paving,
-on a foundation of asphalte.</p>
-
-<div class="figcenter">
- <img src="images/i145.jpg"
- width="auto" height="100%"
- alt="BRIDGE CARRYING THE D. W. AND W. RAILWAY (LOOP LINE)
-OVER AMIENS STREET, DUBLIN"
- />
-<p class="center muchsmaller no-break">BRIDGE CARRYING THE D. W. AND W. RAILWAY (LOOP LINE)
-OVER AMIENS STREET, DUBLIN. &emsp; [<i>To face p. 144.</i></p>
-</div>
-
-<div class="figcenter">
- <a name="fig146"></a>
- <img src="images/i146.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 146, 147, 148, 158, 159"
- title="Figures 146, 147, 148, 158, 159"
- />
-</div>
-
-<p><a href="#fig149">Fig. 151</a> shows cross-section of a plate-girder over-line bridge, 28
-feet span, carrying a public road, 35 feet wide, over a double-line
-railway. The main girders, 2 feet 4 inches deep, are placed at 5 feet
-2 inch centres, and are tied together by plate-iron cross-bracing 2
-feet deep. Jack-arches of brickwork, 9 inches thick, are built in
-between the main girders, the haunching being filled in with concrete.
-The entire surface is covered over and made watertight with asphalte,
-on which is laid the metalling of the roadway. The outside girders are
-made considerably deeper, and have strong cast-iron-plate parapets
-bolted on to the top booms. There is no doubt that jack-arching of
-brickwork or concrete makes a very strong and permanent floorway, but
-its dead weight is very great, and its adoption is
-<!--156.png--><!--157.png--><!--158.png--><!--159.png--><a name="Page_147" id="Page_147"></a><span class="pagenum">[Pg 147]</span>
-not to be recommended
-where iron or steel plate troughing can be obtained at a moderate
-price.</p>
-
-<p><a href="#fig149">Fig. 152</a> gives cross-section of plate-girder over-line bridge, 41 feet
-6 inch span, carrying a public road, 25 feet wide, over three lines of
-way. Two main girders are used, of sufficient depth to form parapets
-or screens for the finished roadway. Plate cross-girders, placed at 6
-feet 6 inch centres, are riveted to the web-plate and lower angle
-irons of main girders; and on these is placed a flooring of plate-iron
-longitudinal troughing to carry the metalled roadway.</p>
-
-<p><a href="#fig153">Fig. 153</a> gives the particulars of a plate-girder over-line bridge,
-carrying an important public road, 35 feet wide, over several main
-lines and sidings. The carriage-way is carried by two girders placed
-at 25-foot centres, and on the lower boom of these are riveted
-lattice-work cross-girders to receive the plate-iron longitudinal
-troughing and roadway. The footpath girders are set at a higher level,
-and the load placed on the lower flange. The curved side brackets
-merely act as bracing between the carriage-way girders and footpath
-girders. A cast-iron-plate parapet is bolted on to the top of each of
-the footpath girders, making a close screen, 6 feet high, above the
-footpath. Lattice-work cross-girders were adopted for the convenience
-of supporting small water mains and gas mains below the road-level.
-The roadway is formed of ordinary metalling, and the footpaths of
-asphalte pavement; the kerbing is of granite, and the side
-water-tables of crushed granite concrete.</p>
-
-<div class="figcenter">
- <a name="fig149"></a>
- <img src="images/i148.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 149 through 152"
- title="Figures 149 through 152"
- />
-</div>
-
-<p><a href="#fig154">Fig. 154</a> is a cross-section of a small uncovered lattice-girder
-footbridge 41 feet span, and 5 feet wide, suitable for small roadside
-stations. The top and bottom flange consist each of two angle irons,
-those in the bottom flange being placed table side upwards, so as to
-bring the entire section of both angle irons fairly into play, and
-also to provide a better bearing for the channel-iron cross-girders
-which carry the planking of the footway. When planking is carried on
-the inside of light angle iron, as in <a href="#fig154">Fig. 155</a>, a severe strain is
-produced at the point <strong>A</strong>; this is entirely obviated by placing the
-bottom angle irons table side upwards, as in <a href="#fig154">Fig. 156</a>. Three of the
-channel-iron cross-girders are extended outwards, and to the ends of
-these are riveted tee-iron stiffeners to steady the main girders. In
-some cases stamped, or ribbed, wrought-iron plates are used for a
-footway, but, although more durable, they do not give such a
-<!--160.png--><!--161.png--><a name="Page_149" id="Page_149"></a><span class="pagenum">[Pg 149]</span>
-secure or
-agreeable foothold as timber. The ascent or descent of the bridge may
-consist either of steps and landings, or of ramps, according to
-circumstances or expediency. Sometimes these bridges are made with
-curved tops, terminating in steps when nearing the steps, or ramps. It
-is very questionable whether such an arrangement is a good one or a
-safe one. There is always a feeling of insecurity when walking over a
-sloping surface broken up by steps, and experience points out that it
-is better to continue the footway level right across to the place
-where the passenger must change his direction to go down the stairs or
-ramp.</p>
-
-<p><a href="#fig154">Fig. 157</a> gives cross-section of a covered lattice-girder footbridge,
-62 feet 6 inches span, and 10 feet wide, suitable for an important
-station. The upper boom of girder consists of two angle irons and top
-plate, and the bottom boom of two channel irons. The cross-girders are
-rolled joist-irons resting on the top tables of the channel irons.
-Four of the cross-girders are extended outwards, and carry plate-iron
-outside vertical brackets to stiffen the main girders. Three-inch
-longitudinal planking is laid down from end to end of the bridge, and
-on this is laid 1¼-inch transverse flooring, in narrow widths, to form
-the walking deck. The footbridge is lighted from the sides by
-continuous glazed sashes fixed in strong wooden framework, as shown.
-The roof is covered with canvas bedded in white lead, and painted in
-the same way as an ordinary carriage roof.</p>
-
-<p>The above examples of under-line and over-line bridges are given more
-with a view of illustrating some of the many different descriptions of
-flooring, rather than to point out or suggest the type of main girder
-to carry the load. The description and size of the main girders can be
-varied to suit the span of the bridge, the requirements of the
-traffic, and the opinion of the designer. For spans up to 50 feet it
-will generally be found that web-plate girders are both simpler and
-cheaper than lattice or truss girders; at the same time, there are
-occasions where plate girders can be advantageously adopted for very
-much larger spans, as, for instance, in the example given in <a href="#fig145">Fig. 145</a>,
-where the deep plate girders form a most efficient screen.</p>
-
-<div class="figcenter">
- <a name="fig153"></a>
- <img src="images/i150.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 153"
- title="Figure 153"
- />
-</div>
-
-<p><a href="#fig160">Figs. 160</a> to 194 give diagram sketches of a few out of the many forms
-of open, or truss, girders which have been adopted for large spans.
-There are many types from which to make a selection, each one
-possessing its own special features and
-<!--162.png--><!--163.png--><a name="Page_151" id="Page_151"></a><span class="pagenum">[Pg 151]</span>
-advocates. In working out the
-details of any, or all of them, there are some points which should
-always be kept in mind when deciding the distribution of material in
-the main booms. Rain-water, or moisture of any kind, is the great
-enemy of wrought-iron or steel work, and therefore the plates, angles,
-tees, or channel sections, should be so arranged as to afford the
-least possible facility for the collection or lodgment of water. With
-open, level booms, as in <a href="#fig137">Figs. 137</a>, <a href="#fig138">139</a>, <a href="#fig140">140, 144</a>, and <a href="#fig145">145</a>, the
-rain-water cannot collect, but runs off at the sides, and the plates
-are quickly dried by the sun and wind. With trough booms, as in <a href="#fig146">Fig.
-158</a>, the collected rain-water can only get away through holes drilled
-for the purpose in the bottom plates. These holes are liable to become
-choked up, but even when open they rarely carry off all the
-accumulated water; some of it remains to corrode the plates, and is
-only dried up by evaporation. The inside of trough booms should be
-constantly inspected, and the exposed plates more frequently painted
-than the rest of the girder. In a similar manner, in small double-web
-lattice girders, with the lattice-bars inserted between two angle
-irons, as in <a href="#fig146">Fig. 159</a>, the rain-water finds its way into the spaces at
-<strong>A</strong>, <strong>A</strong>, in spite of the most careful packing or filling with cement
-or asphalte. Numbers of small girders of this latter type have had to
-be taken out after a comparative short life, in consequence of the
-great corrosion and wearing away of the lower ends of the lattice-bars
-and angle irons into which they were inserted.</p>
-
-<p>It is most essential, also, that all portions of the girder-work
-should be conveniently accessible for inspection and painting.
-Complicated connections, and parts which are difficult to examine, are
-liable to be overlooked, or, at the best, only painted in a very
-imperfect manner. Neglected corners soon create deterioration, the
-paint scales off, corrosion commences, and the working section is
-gradually reduced. A discovered weakness in some of the important
-parts points to an early condemnation of the entire structure. The
-difficulty of access to the interior of box or tubular girders,
-especially those of small or moderate dimensions, is a great objection
-to that type of girder. Experience has pointed out that open girders,
-free and exposed to the light and air, can be so much more effectually
-inspected and painted.</p>
-
-<div class="figcenter">
- <a name="fig154"></a>
- <img src="images/i152.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 154, 155, 156, 157"
- title="Figures 154, 155, 156, 157"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig160"></a>
- <img src="images/i153.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 160 through 168"
- title="Figures 160 through 168"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig169"></a>
- <img src="images/i154.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 169 through 176"
- title="Figures 169 through 176"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig177"></a>
- <img src="images/i155.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 177 through 183"
- title="Figures 177 through 183"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig184"></a>
- <img src="images/i156.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 184 through 191"
- title="Figures 184 through 191"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig192"></a>
- <img src="images/i157.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 192 through 194"
- title="Figures 192 through 194"
- />
-</div>
-
-<p>Perhaps one of the most anxious tasks which falls to the lot of an
-engineer is the renewal of under-line bridges and viaducts on a
-working line. On a new line in course of construction the
-<!--164.png-->
-<!--165.png-->
-<!--166.png-->
-<!--167.png-->
-<!--168.png-->
-<!--169.png-->
-<!--170.png--><a name="Page_158" id="Page_158"></a><span class="pagenum">[Pg 158]</span>
-entire site
-of the work is at the disposal of the erectors, and the building of a
-bridge or viaduct can be carried on with a freedom which cannot be
-obtained on an open line. On a working railway, the train service must
-be kept going, irrespective of renewals, and very often the best that
-can be done is to reduce the double line to single line working at the
-site of the operations. It is not always expedient or possible to make
-a temporary bridge and diverted line for traffic purposes, as the
-expenditure to be incurred might be too great to warrant the outlay,
-or there may be local difficulties to effectually prevent the
-introduction of a provisional structure. The taking down of one half
-of the old structure may necessitate the removal of stays and bracing
-affecting the stability of the half remaining to carry the traffic,
-and thus render temporary shoring and bracing necessary. The erection
-of the new work in such a limited space has to be watched with great
-care; all cranes, lifting appliances, and scaffolding must be kept
-clear of vehicles moving over the running-line, and very frequently it
-is found prudent to cease erecting operations during the passage of a
-train.</p>
-
-<p>In very many cases of renewals, the description and arrangement of the
-old structure will materially influence or control the design for the
-new one, and the details of the latter must be schemed out so as to
-disturb as little as possible the stability of the old work remaining
-as the working road.</p>
-
-<p>The following list gives the lengths of the main spans of some railway
-bridges, and may be found useful for <span style="white-space:nowrap;">reference:&mdash;</span></p>
-
-<p class="p2 center"><span class="sc">Lengths of Main Spans of some Large Railway Bridges.</span></p>
-
-<table summary="lengths of large railway bridge spans">
-<tr><th class="center" scope="col">Name.</th><th class="center" scope="col">&emsp;Span.&emsp;</th><th class="center" scope="col">Description.</th></tr>
-<tr><td></td><td class="smaller centernobox l r">feet.</td>
-</tr>
-<tr><td class="leftex">Forth Bridge</td><td class="rightm l r">1,710</td><td class="leftex">Cantilever.</td>
-</tr>
-<tr><td class="leftex">Niagara</td><td class="rightm l r">821</td><td class="leftex">Suspension.</td>
-</tr>
-<tr><td class="leftex">Sukkur</td><td class="rightm l r">820</td><td class="leftex">Cantilever.</td>
-</tr>
-<tr><td class="leftex">Poughkeepsie, U.S.A.</td><td class="rightm l r">548</td><td class="leftex">Cantilever.</td>
-</tr>
-<tr><td class="leftex">Douro</td><td class="rightm l r">525</td><td class="leftex">Arch.</td>
-</tr>
-<tr><td class="leftex">St. Louis</td><td class="rightm l r">520</td><td class="leftex">Arch.</td>
-</tr>
-<tr><td class="leftex">Cincinnati</td><td class="rightm l r">515</td><td class="leftex">Linville truss.</td>
-</tr>
-<tr><td class="leftex">Haarlem</td><td class="rightm l r">510</td><td class="leftex">Arch.</td>
-</tr>
-<tr><td class="leftex">Kuilemburg</td><td class="rightm l r">492</td><td class="leftex">Lattice bow.</td>
-</tr>
-<tr><td class="leftex">St. John’s River</td><td class="rightm l r">477</td><td class="leftex">Cantilever.</td>
-</tr>
-<tr><td class="leftex">Niagara</td><td class="rightm l r">470</td><td class="leftex">Cantilever.</td>
-</tr>
-<tr><td class="leftex">Britannia</td><td class="rightm l r">460</td><td class="leftex">Tube.</td>
-</tr>
-<tr><td class="leftex">Ohio River,  Pennsylvania</td><td class="rightm l r">442</td><td class="leftex">Pratt through truss.
-<!--171.png--><a name="Page_159" id="Page_159"></a><span class="pagenum">[Pg 159]</span></td>
-</tr>
-<tr><td class="leftex">Saltash</td><td class="rightm l r">434</td><td class="leftex">Tube and girder.</td>
-</tr>
-<tr><td class="leftex">Hawkesberry Viaduct</td><td class="rightm l r">410</td><td class="leftex">Compound truss.</td>
-</tr>
-<tr><td class="leftex">Conway</td><td class="rightm l r">400</td><td class="leftex">Tube.</td>
-</tr>
-<tr><td class="leftex">Vistula</td><td class="rightm l r">397</td><td class="leftex">Lattice.</td>
-</tr>
-<tr><td class="leftex">Spey River, Garmouth, N.B.</td><td class="rightm l r">350</td><td class="leftex">Bowstring.</td>
-</tr>
-<tr><td class="leftex">St. Laurence</td><td class="rightm l r">330</td><td class="leftex">Tube.</td>
-</tr>
-<tr><td class="leftex">Hamburg</td><td class="rightm l r">316</td><td class="leftex">Double bow.</td>
-</tr>
-<tr><td class="leftex">Cologne</td><td class="rightm l r">313</td><td class="leftex">Lattice.</td>
-</tr>
-<tr><td class="leftex">Runcorn</td><td class="rightm l r">305</td><td class="leftex">Lattice.</td>
-</tr>
-<tr><td class="leftex">Sunderland</td><td class="rightm l r">300</td><td class="leftex">Bowstring.</td>
-</tr>
-<tr><td class="leftex">Rondout Bridge, Buffalo</td><td class="rightm l r">264</td><td class="leftex">Pratt through truss.</td>
-</tr>
-<tr><td class="leftex">Newark Dyke (New)</td><td class="rightm l r">259</td><td class="leftex">Lattice bow.</td>
-</tr>
-<tr><td class="leftex">Tay Bridge (New)</td><td class="rightm l r">245</td><td class="leftex">Lattice bow.</td>
-</tr>
-<tr><td class="leftex">Ohio River, Louisville</td><td class="rightm l r">245</td><td class="leftex">Fink truss.</td>
-</tr>
-<tr><td class="leftex">Beaver Bridge, Pennsylvania</td><td class="rightm l r">230</td><td class="leftex">Pratt deck truss.</td>
-</tr>
-<tr><td class="leftex">Craigellachie Bridge</td><td class="rightm l r">200</td><td class="leftex">Lattice.</td>
-</tr>
-<tr><td class="leftex">Rohrbach Bridge, St. Gothard River</td><td class="rightm l r">197</td><td class="leftex">Wrought-iron arch.</td>
-</tr>
-<tr><td class="leftex">Windsor Bridge</td><td class="rightm l r">187</td><td class="leftex">Bowstring.</td>
-</tr>
-<tr><td class="leftex">Victoria Bridge over Thames</td><td class="rightm l r">175</td><td class="leftex">Wrought-iron arch.</td>
-</tr>
-<tr><td class="leftex">Shannon River Bridge</td><td class="rightm l r">165</td><td class="leftex">Bowstring.</td>
-</tr>
-<tr><td class="leftex">Carron Bridge over Spey</td><td class="rightm l r">150</td><td class="leftex">Cast-iron arch.</td>
-</tr>
-<tr><td class="leftex">Preston Viaduct</td><td class="rightm l r">102</td><td class="leftex">Cast-iron arch.</td>
-</tr>
-<tr><td class="leftex b">Trent River Bridge</td><td class="rightm l r b">100</td><td class="leftex b">Cast-iron arch.</td>
-</tr>
-</table>
-
-<p class="p2"><strong>Retaining Walls.</strong>&mdash;Instances frequently occur during the construction
-of a railway where it is advisable, if not absolutely necessary, to
-substitute retaining walls in preference to forming the slopes of
-cuttings and embankments.</p>
-
-<p>The excavation of a cutting may be greatly reduced in quantity by
-introducing low retaining walls, as in <a href="#fig195">Fig. 195</a>, and the saving in the
-material to be removed will be all the more important in those cases
-where cutting is in excess of embankment.</p>
-
-<p>The amount of filling for an embankment and the land on which it has
-to be formed may both be considerably diminished by building a low
-retaining wall, say 6 or 7 feet high, at the foot of the slope, as
-shown in <a href="#fig195">Fig. 196</a>. Such a retaining wall makes a most efficient fence
-and well defined boundary of property.</p>
-
-<div class="figcenter">
- <a name="fig195"></a>
- <img src="images/i160.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 195 through 201"
- title="Figures 195 through 201"
- />
-</div>
-
-<p>The policy of adopting low retaining walls in cases like the
-<!--172.png--><!--173.png--><a name="Page_161" id="Page_161"></a><span class="pagenum">[Pg 161]</span>
-above
-will depend mainly upon the cost of building materials as compared
-with the cost of earthwork and land.</p>
-
-<p>Where land is very valuable, and where residential property, streets,
-or roads must be interfered with as little as possible, the retaining
-walls may have to be carried up to the level of the original surface
-of the ground, as in <a href="#fig195">Fig. 197</a>, which is shown as for a cutting 25 feet
-deep. The walls may be built of masonry, brickwork, or concrete, or a
-combination of them, and the dimensions or thickness will depend upon
-the description of material to be supported. Weeping holes, or small
-pipe drains, should be formed in the walls, a little above formation
-level, to take away any water which may collect at the back.</p>
-
-<p>Where the cutting is through soft, wet, treacherous clay, liable to
-slip or expand, it may be necessary to insert arched thrust girders
-extending from side to side, as in <a href="#fig195">Fig. 198</a>, so that the outward
-pressure against the one wall may counteract against the outward
-pressure of the other. The thrust girders should be placed at from 10
-to 15 feet centres, and be well braced together in plan to enable them
-the better to resist any tendency of bulging out of the walls.</p>
-
-<p>A similar arrangement of high retaining wall may be introduced in
-embankment to lessen the encroachment on streets or public roads, as
-shown in <a href="#fig195">Fig. 199</a>.</p>
-
-<p>In making a railway through thickly populated towns, it is generally
-preferable to construct the line on arches rather than on earthwork
-filling between two high retaining walls. The numerous openings are
-available for future streets, or means of communication from one side
-to the other, and the arches themselves can be profitably utilized for
-stables, stores, offices, and workshops.</p>
-
-<p><a href="#fig195">Fig. 200</a> shows a narrow rocky pass with deep rapid river on the one
-hand and high cliffs on the other, the only available ledge being
-already occupied by a public highway. By building a retaining wall, as
-indicated on the sketch, and excavating a little out of the cliff,
-space may be obtained for a line of railway; or the arrangement may
-have to be reversed, and the retaining wall for the railway built
-along the margin of the river, as in <a href="#fig195">Fig. 201</a>.</p>
-
-<p>In both the cases, <a href="#fig195">Figs. 200 and 201</a>, not only must there be a number
-of weeping holes left in the lower part of the wall, but there must be
-sufficient well-built drains and culverts under the
-<!--174.png--><a name="Page_162" id="Page_162"></a><span class="pagenum">[Pg 162]</span>
-filling and through
-the wall to carry away all ordinary or flood water coming down from
-the cliffs and hills above. Where a retaining wall is built along the
-margin of a river, the lower portion, which will be in contact with
-the water when the river is full, should be constructed of selected
-large heavy stones to withstand the scouring action of the water, and
-any brushwood or floating timber which may be brought down by flood
-water.</p>
-
-<p>Where retaining walls are built to support wet clay, or in embanked
-places on wet side-lying ground, the efficiency of the work will be
-much increased by constructing a layer, two or three feet in
-thickness, of dry, flat, bedded stones carefully hand-laid, from the
-foundation to the top of the wall, as shown in <a href="#fig195">Fig. 199</a>.</p>
-
-<p>These dry stones form a continuous vertical drain to take away water
-from any part of the earthwork down to the outlets left in the lower
-portion of the wall.</p>
-
-<p>The building of retaining walls entirely of dry stone is very
-questionable economy, and entails a constant expenditure in
-maintenance and renewal. The working out of one stone loosens the
-surrounding portion of the wall, and if not at once repaired, a length
-of the wall will fall down, bringing with it a large quantity of the
-earthwork.</p>
-
-<p>If readily obtained, large heavy stones should be selected for the
-coping of retaining walls, so as to minimize as much as possible the
-chance of their disturbance or displacement. Where lighter stones have
-to be used, or bricks laid on edge, they should be bedded and pointed
-in cement.</p>
-
-<p>In many places it is necessary to form wide and massive foundations of
-concrete on which to build the retaining wall; and in some cases of
-soft, treacherous ground, timber piling may be necessary.</p>
-
-<p class="p2"><strong>Tunnels.</strong>&mdash;It would be difficult to assign a date to the first
-examples of subterranean works constructed for utilitarian purposes.
-Nature had furnished so many grand specimens of caves, grottoes, and
-underground passages formed in the solid rock, that man soon grasped
-the principle, and essayed to carry out similar works on his own
-account. The early attempts would probably be limited to forming
-places of shelter, storage or security. Advantage would be taken of
-those rocks which from their locality, accessibility, and compactness
-of material, promised favourable results. The appliances being few and
-<!--175.png--><a name="Page_163" id="Page_163"></a><span class="pagenum">[Pg 163]</span>
-primitive, the work of construction would be laborious and slow. So
-long, however, as the workers restricted their operations to the solid
-rock, they had merely to contend against the hardness of the material,
-as the opening or passage-way, once made, required no further support
-or attention; but as the wave of progress swept onward, man was
-compelled to deviate from the lines originally followed by nature, and
-had to form his subterranean pathway through softer material, where
-the workings required substantial support. The search for minerals of
-various kinds led to the driving of long headings or galleries
-underground, and as these had frequently to penetrate through strata
-of a soft and yielding character, strong timber framework had to be
-introduced to afford stability to the works, and safety to the
-workers. For ordinary mining operations, strong rough timber supports
-may meet all requirements, and may last until the heading is worked
-out and abandoned; but for subterranean passages or tunnels which are
-intended to form permanent means of communication, the strongest and
-most durable materials must be used to protect the interior as far as
-possible from deterioration or decay. Heavy timbering might be
-sufficient for mere temporary purposes, but substantial masonry or
-brickwork side walls and arching became necessary for permanent work
-in those portions where the tunnel required artificial support.</p>
-
-<p>The first tunnels of any importance were most probably those
-constructed for canal purposes. Many of them were of considerable
-magnitude, and in some instances were from two to three miles in
-length. They were substantially lined with masonry or brickwork at all
-places where the tunnel passed through soft material or loose rock,
-and from the solid nature of the work, and the many years they have
-been in existence, they thoroughly testify to the ability of the
-constructors.</p>
-
-<p>The introduction of railways involved the making of a large number of
-tunnels, perhaps more so in the beginning, when it was thought that
-the use of the locomotive would be confined to very moderate
-gradients, and when engineers hesitated to adopt the steeper inclines
-and sharper curves which form the practice of modern times. Another
-element of consideration also consisted in the fact that the first
-railways were designed to connect the most populous and busiest
-districts, where the prospects of heavy traffic would appear to
-warrant a large outlay for works of construction. As the system spread
-and
-<!--176.png--><a name="Page_164" id="Page_164"></a><span class="pagenum">[Pg 164]</span>
-railways extended further away from the important centres, the
-probabilities of traffic would become less promising, and efforts
-would be made to keep down cost of construction, and avoid tunnel work
-as much as possible.</p>
-
-<p>It is not easy to define where cutting should end and tunnelling
-begin. There is no practical difficulty in making a cutting 50, 60, or
-70 feet deep, with slopes to suit the material excavated, and the
-estimated cost per yard forward may even compare favourably with the
-cost of average tunnel-work. But there are other questions which must
-be kept in view&mdash;the time required to form the cutting, the space to
-be obtained on which to deposit the enormous quantity of excavated
-material, and the probable difficulty in obtaining the large area of
-land necessary for the cutting.</p>
-
-<p>Before deciding the actual position of a tunnel, both as to line and
-level, it is necessary to obtain the most reliable information
-possible regarding the strata through which it has to pass. In
-addition to the geological indications on the surface and in the
-locality, borings should be made, and trial holes or shafts sunk along
-the proposed centre line of the work, and from these an approximately
-accurate longitudinal section can be laid down on paper, showing the
-respective layers of material to be cut through, and the angle at
-which they lie. With these particulars before him, the engineer may,
-in some cases, consider it more prudent to change the position of the
-tunnel in preference to incurring specially difficult or tedious work
-in dealing with some recognized unfavourable material. Occasionally
-the route may be slightly varied and better material obtained, but
-very frequently there is little to be gained except by a wide
-deviation from the original line.</p>
-
-<p>Solid rock, except for the slow progress, is perhaps the most
-favourable material for tunnelling, as the timbering, side walling,
-and arching can be almost, if not entirely, dispensed with.</p>
-
-<p>Loose rock, although more readily removed, necessitates strong
-timbering to prevent large masses breaking away and falling into the
-tunnel.</p>
-
-<p>Some clays are very compact and tenacious, and will stand well with
-moderate timbering, but even these should not be left long before
-following up with the side walls and arching.</p>
-
-<p>Many clays give much trouble by expanding, or swelling out, when the
-excavation penetrates the layer, and although extra
-<!--177.png--><a name="Page_165" id="Page_165"></a><span class="pagenum">[Pg 165]</span>
-strong timbering
-may be used, and be placed closer together, the logs and planks are
-frequently bulged out and broken by the action of the clay. Specially
-strong supports are required for this description of clay, and extra
-thickness of material in the permanent work of side walls and arching.</p>
-
-<p>Solid unbroken beds of chalk are not difficult to cut through: the
-material is easy to work, and the excavation will stand with ordinary
-timbering; but where the chalk is broken and intersected with deep
-pockets of gravel and sand, the operations are very much impeded. The
-loose material, once set free by cutting through the confining barrier
-of chalk, will quickly fall into and fill up the excavation if not
-held back by strong timbering. Side walls and arching are generally
-necessary for tunnels through chalk.</p>
-
-<p>Soft wet clay, quicksands, or other strata having springs of water
-percolating through them, are serious obstacles in the way of
-expeditious tunnelling. No sooner is one cube yard of this soft
-material removed than another slides down, or is washed down, to take
-its place. When once the excavation taps the water-bearing strata,
-large volumes of water will find their way into the workings, and must
-be conveyed away to the mouth of the tunnel, or pumped up through the
-nearest shaft. The timbering of the sides and roof through this
-description of working is very tedious, and attended also with a
-considerable amount of risk. The absence of really solid ground on
-which to place or shore up the supports, taxes the skill of the
-excavators, and very often, when a short length has been made
-apparently secure, it will come down with a run, compelling all hands
-to beat a hasty retreat. The permanent lining through such treacherous
-material should follow the excavation very closely, and special care
-should be exercised in building the walls, arching and invert.</p>
-
-<p>In the excavation through stratified rocks it is necessary to note
-carefully the lie of the strata, whether horizontal, vertical, or
-shelving, as with each one the excavators are exposed to risks,
-against which every precaution should be taken. A large horizontal
-slab of solid-looking rock will suddenly break and fall down without
-any warning. A heavy mass from a vertical layer, perhaps unkeyed, or
-loosened, by an adjacent blasting operation, drops down when least
-expected; and pieces from the high side of the shelving layers detach
-themselves and slide into the working in a most unaccountable manner.</p>
-
-<p><!--178.png--><a name="Page_166" id="Page_166"></a><span class="pagenum">[Pg 166]</span>
-No attempt should be made to carry a tunnel through material which has
-been disturbed or at all affected by any natural slip or cleavage, as
-although the strata may be hard and compact in themselves, they have
-really no solid or fixed foundation. The sliding away, once initiated,
-is certain to continue, and, accelerated by the tunnelling operations,
-will most likely, sooner or later, crush in the tunnel and sweep away
-every vestige of the work. Amongst the great mountain ranges these
-natural disturbances are by no means rare, and it will be wiser to
-keep away from their locality, even at the expense of a longer tunnel.
-Unfortunately, instances are on record of tunnels made, or in course
-of construction, through hillsides which had already commenced to
-slide away from the more solid rock, and the ultimate results were a
-further sliding away and total destruction of the work.</p>
-
-<p>The lower slopes and outlying portions of high mountains are the most
-exposed to these natural slips, and they should be most carefully
-studied before commencing any tunnelling operations through them.</p>
-
-<p>To facilitate drainage, it is essential that a railway tunnel should
-be laid down with a gradient or gradients falling in the direction of
-one or both ends of the tunnel. In nearly all tunnels a considerable
-amount of water finds its way in through the weeping-holes left for
-that purpose in the side walls, and must be carried away in suitable
-drains. If the quantity of water be small, ordinary water-tables, one
-on each side, may be sufficient; but for large volumes of water it
-will be necessary to build substantial side-drains, or an ample
-culvert below the level of the rails.</p>
-
-<p>The gradients in a tunnel should be moderate, and not by any means
-excessive, or likely to tax the hauling powers of the locomotives.
-When an engine is working nearly to the utmost of its power on a steep
-tunnel incline, and the speed has become very slow, the exhaust
-vapours or gases from the funnel strike the arching with great force,
-and are deflected down on to the footplate in such dense volumes as to
-almost suffocate the driver and fireman. The writer will never forget
-two or three trying experiences in foreign tunnels, when he and the
-engine-staff were compelled to leave the footplate and climb forward
-to the front of the funnel, leaving the engine to work its way alone.
-Except for very short tunnels it is wiser to have easy inclines, and
-to restrict the steep gradients to the open line, where
-<!--179.png--><a name="Page_167" id="Page_167"></a><span class="pagenum">[Pg 167]</span>
-the very slow
-travelling, or even the coming to a stand from “slipping,” may not
-produce unpleasant or alarming consequences.</p>
-
-<p>In tunnels of any length it is usual, where possible, to construct
-shafts extending from the surface of the ground overhead down to the
-tunnel below. These shafts serve the double purpose of enabling the
-excavation to be carried on at an increased number of faces, and act
-as permanent ventilators after completion. In some cases the shafts
-are sunk exactly over the centre line of the tunnel, in others a few
-yards away from the centre line. The latter arrangement, if not quite
-so convenient for hoisting material while carrying on the excavations,
-has certainly the great after advantage that anything falling or
-maliciously thrown down the shaft cannot strike a passing train. The
-short side-gallery, or space between the tunnel and the shaft,
-provides a good refuge for workmen employed in repairs, and a
-convenient site for storing a few materials advisable to keep on hand.</p>
-
-<p>Occasionally favourable opportunities present themselves for making
-horizontal shafts. For a portion of its length the tunnel may be
-located at no very great distance from the precipitous sides of some
-deep mountain ravine, or run near to the cliffs on the sea-coast, and
-advantage can be taken to drive a lateral heading or gallery through
-which the material from the tunnel excavation may be conveyed and
-thrown out into the gorge or seashore below.</p>
-
-<p>In many cases the surface of the ground rises so abruptly from the
-faces of the tunnel and ascends to so great a height, that shafts of
-any kind are entirely out of the question, and the whole of the work
-must be carried on from the two ends. The rate of progress is
-consequently much slower, and the ventilation more difficult. In a
-shaftless tunnel of considerable length, and with a frequent train
-service, the question of providing suitable appliances for promoting
-artificial ventilation is of the utmost importance.</p>
-
-<p>When the centre line of the tunnel has been accurately set out on the
-ground, and the levels of the different parts of the work decided, the
-construction of the shafts and the driving of the headings can be
-commenced. Working shafts intended to serve for permanent ventilation
-are generally made nine or ten feet or more in diameter, and are
-usually lined with substantial
-<!--180.png--><a name="Page_168" id="Page_168"></a><span class="pagenum">[Pg 168]</span>
-brickwork or masonry. When the well-like
-excavation has been carried down a few yards, or as far as it can be
-taken without the risk of the earth falling in upon the sinkers, a
-strong curb of hard wood or iron of the same diameter as the finished
-shaft is laid down perfectly level and to exact position, and on this
-curb the ring or lining of brickwork or masonry is built up to the
-level of the ground. The first length finished, the excavation
-downwards is resumed, and the interior lining continued, either by
-allowing the first length to slide down as the material below is
-gradually removed, and building further lining on the top, or by
-excavating and propping up the curbing with strong timbers below. When
-working to the latter method, stout wooden props of convenient length,
-stepped on to sole-pieces, are adjusted to the under side of the
-wooden curb above, the material is then removed for the thickness of
-the brickwork or masonry, and another curb accurately set to level and
-position; on this is built a length of lining up to the first curb.</p>
-
-<p>This work of under-building or under-pinning must be carried out with
-great care and in segments; no props must be removed until the curb
-immediately above is well supported by the new lining, and the inside
-of the lining must be watched and tested to prevent any tilting. All
-spaces at the back of the work must be filled in and well packed with
-hard dry material. As the shaft is continued downwards the mode of
-working may have to be varied; different descriptions of material may
-be encountered, and blasting, shoring, and pumping may each in turn be
-necessary.</p>
-
-<p>When down to the full depth, the lower length of the shaft will have
-to be securely supported by strong timbers, until it can be properly
-built into and incorporated with the arching of the tunnel or side
-gallery.</p>
-
-<p>The completion of the shaft enables the workings to be commenced on
-each side, the excavated material can be hoisted to the surface, and
-building material lowered down. When the tunnel works are finally
-finished, the lining of the shaft should be carried up until it is 15
-or 20 feet above the level of the surface of the ground, and a
-dome-shaped iron grating placed on the top as a protection against
-stones or other articles which malicious persons might attempt to
-throw down the shaft.</p>
-
-<p>Some shafts are only intended for the temporary purpose of lifting the
-excavations from below, or lowering building materials
-<!--181.png--><a name="Page_169" id="Page_169"></a><span class="pagenum">[Pg 169]</span>
-down, and when
-the work is completed they are filled in again and closed. These
-service shafts are generally made square in section, and are merely
-lined with wood. Strong vertical timbers are placed at the four
-corners, to which horizontal double cross-pieces are bolted, thick
-planking being placed vertically at the back of these cross-pieces to
-support the sides of the excavation.</p>
-
-<p>The <em>heading</em> of a tunnel is a narrow passage or gallery cut
-through from end to end of the works in the direction of the centre
-line. Where there are shafts, the cutting of the heading can be pushed
-on from several points, and be completed much more rapidly than when
-the working is restricted to the two ends. Headings are usually made
-just sufficiently large for the miners to work, say about 5 feet 6
-inches high by about 3 feet wide, the object being rather to expedite
-the driving of the driftway than to remove large masses of material.
-They must be set out with great accuracy, and be constantly checked as
-the driving is in progress. When completed from end to end, the centre
-line can be checked throughout, and the course actually taken compared
-with the course intended. If there has been much variation in the
-narrow pioneer pathway, either in line or level, the amount of the
-divergence must be rectified when ranging the final centre line for
-the full-size excavation.</p>
-
-<p>Tunnels cannot always be delayed until the heading is cut through for
-the entire length. In many cases the heading, the full-size
-excavation, and the permanent lining have all to be carried on at the
-same time, but as the work of the heading is smaller in extent, that
-portion of the operations can usually be kept well in advance of the
-others. The critical moment arrives when the headings from opposite
-directions meet, as any deviation or want of coincidence must be
-adjusted in the portion of the tunnel still remaining to be opened out
-to full size. Some tunnels of moderate length have been constructed
-without any heading at all, the excavation being taken out to the full
-dimensions from the commencement.</p>
-
-<p>The heading of a tunnel assists not only in the correct alignment of
-the work, but furnishes at the same time an accurate knowledge of the
-strata passed through. It is also of service for ventilation,
-communication, and drainage.</p>
-
-<p>In some cases the heading is driven at the bottom of the tunnel
-section, as in <a href="#fig204">Fig. 211</a>, and in others at the top, as in
-<!--182.png--><a name="Page_170" id="Page_170"></a><span class="pagenum">[Pg 170]</span>
-<a href="#fig202">Figs. 202</a> and
-<a href="#fig204">204</a>. Many of the earlier tunnels were constructed on the former
-system, while of late years the latter method has been very largely
-adopted. The bottom heading may perhaps in some instances be more
-efficacious for drainage, but it is very liable to be frequently
-choked up when taking out the excavation to the full size, and the
-lower surface is much cut up by the movement and conveyance of
-materials. Another disadvantage arises from the necessity of removing
-such a large amount of the cutting approaching the tunnel entrance
-before a beginning can be made to the bottom heading. The top heading
-has the advantage that it requires less removal of open cutting
-previous to its commencement, and, being high up in position, there is
-less chance of its being stopped up by falling material, the finished
-excavations being carried out on the sides and below the heading.</p>
-
-<p>Where the headings are cut through solid rock, stiff shale, or compact
-chalk, little or no supports are necessary, but where they pass
-through clay or loose material, timbering will be required for sides,
-roof, and floor. Rough round poles, about 6 inches in diameter, are
-generally used for verticals, and are firmly secured to transverse
-sole-pieces, and on the top of these verticals strong transverse
-top-sills are fastened by means of rough tenons or checks. Strong
-boards are inserted at the back of this framework to keep the earth
-from falling into the working. The distance apart of the verticals
-will depend upon the description of material excavated; in very soft
-places they will have to be placed very close together, but where
-fairly sound and tenacious they may be placed at about 3-foot centres.
-The excavated material must be conveyed away to the entrance of the
-heading in small hand-trucks running on planks or light rails.</p>
-
-<p>The widening out of the excavation to the full size will be a
-repetition on a large scale of the work carried out in the heading,
-with the difference that, the exposed surfaces being of so much
-greater extent, extra care and precautions must be taken with the
-framework and shoring of the timbering.</p>
-
-<div class="figcenter">
- <a name="fig202"></a>
- <img src="images/i171.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 202 and 203"
- title="Figures 202 and 203 "
- />
-</div>
-
-<p>The form and arrangement of the timbering, as well as the number,
-sizes, and positions of the pieces, must be determined by the material
-of the excavation and the contour line of the finished arching or
-lining. The framework, which would be sufficient to support ordinary
-soft material, must be largely augmented both
-<!--183.png--><!--184.png--><a name="Page_172" id="Page_172"></a><span class="pagenum">[Pg 172]</span>
-in quantity and scantling
-to meet the requirements for wet treacherous clay.</p>
-
-<p><a href="#fig202">Figs. 202 and 203</a> give end view and longitudinal section of timber
-framework frequently adopted for average tunnel work. The positions of
-the different pieces will explain themselves and the duty they have to
-perform. The main struts, or raking pieces, which have to sustain
-great pressure, may be shored against the finished lengths of masonry
-or brickwork. The timbering of the sides can be removed as the lining
-proceeds, but in many cases the round logs and boards near the crown
-cannot be withdrawn, and have to be left in the work, the space
-between the top of the arching and under side of the boards being
-firmly packed with brickwork, masonry, or dry rubble stonework.</p>
-
-<p>As the tunnel lining is generally carried forward in short lengths,
-following up the main excavations, the centering for the arching
-should be of such description that it can be readily transferred or
-moved forward as the work proceeds. The form of the centering, and the
-spacing of its upright supports, must admit of sufficient width for
-one or more lines of rails for the waggons required to remove the
-excavated <i lang="fr">débris</i> and convey the building materials used in the
-lining.</p>
-
-<p>Picks, bars, and shovels are the tools used in the excavation of the
-softer material and loose disintegrated rock, but for the hard rock,
-blasting will be necessary. The tunnel opening being comparatively
-small, only moderate blasting charges can be used with safety, and
-these must be placed so as to break up the rock-bed in a suitable
-manner for working, and without shaking or damaging the already
-completed excavation. Ordinary hand-drills, or <em>jumpers</em>, may be used
-for forming the charge holes, a number of them being at work at the
-same time, and the charges fired very closely one after the other. As
-the blasting operations necessitate the retiring of the miners to a
-considerable distance, out of the way of flying fragments, and the
-remaining away until the foul air has been dispelled, it is advisable
-to fire off several charges about the same time, and thus minimize as
-much as possible the stoppage to the drilling and clearing away the
-loosened material.</p>
-
-<div class="figcenter">
- <a name="fig204"></a>
- <img src="images/i173.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 204 through 211"
- title="Figures 204 through 211"
- />
-</div>
-
-<p>Mechanical drills, worked by compressed air or other motive-power, are
-now very extensively used where the rock is solid and continuous. They
-are much more expeditious than the hand
-<!--185.png--><!--186.png--><a name="Page_174" id="Page_174"></a><span class="pagenum">[Pg 174]</span>
-drills, but they are costly in
-their installation, and also in their working and maintenance.</p>
-
-<p>In some tunnels, where the material has been firm and dry, the upper
-portion of the excavation has been first removed, and the masonry and
-brickwork lining built in position down to about the springing of the
-arch, the remainder of the excavation being afterwards taken out, and
-the side walls built by means of shoring and underpinning.</p>
-
-<p>In other tunnels the complete section has been excavated and timbered,
-and the work of building commenced from the foundation of the side
-walls. A strong continuous invert from side wall to side wall is
-necessary where passing through soft swelling clay or loose strata
-intersected with small streams of water. Where the material is very
-solid and dry, it is not necessary to introduce inverts, but the
-foundations of the side walls should be laid at such a depth below
-rail-level as not to be affected by drain-water running through the
-tunnel.</p>
-
-<p>The side walls and arching may be either of masonry or brickwork, but
-should be of the best description, especially for the facework. For
-brick arching only the best hard-burnt bricks should be used, and the
-inner or exposed ring should consist of selected hard fire-bricks to
-withstand the heat and gases escaping from the funnels of the
-locomotives. The thickness of the side walls and arching will depend
-upon the description of material to be supported. In some places a
-comparative thin lining may be sufficient, while in others extra
-thickness must be given to resist the great pressure exerted by
-expanding clay and loose wet strata.</p>
-
-<p>Weeping-holes, or small drain-pipes, placed low down must be left in
-the side walls every three or four yards, or closer in very wet
-places, to allow the water collected at the back of the walls to
-escape into the side drains of tunnel. In building the arch portion
-every effort should be made to have close solid work without any open
-joints or spaces through which the water may run, and the crown of the
-arch and a few feet down on each side should be coated with cement or
-asphalte to lead all water away from the top to the sides. Water
-dripping from the under side of the arch on to the line is a great
-destructor of the permanent way materials, especially the fastenings;
-and bolts, nuts, fish-plates, and spikes placed in a wet dripping
-tunnel will not last half the time they would out in the open line,
-where they would have the sun and wind to dry them.</p>
-
-<div class="figcenter">
-<!--187.png--><a name="Page_175" id="Page_175"></a><span class="pagenum">[Pg 175]</span>
- <a name="fig212"></a>
- <img src="images/i175.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 212 through 219"
- title="Figures 212 through 219"
- />
-</div>
-
-<p><!--188.png--><a name="Page_176" id="Page_176"></a><span class="pagenum">[Pg 176]</span>
-Small arched recesses or niches should be formed in the side walls at
-convenient distances to serve as refuges for platelayers or others
-working in the tunnels.</p>
-
-<p>It is most essential that the space between the masonry and brickwork
-lining and the facework of the excavation should be carefully filled
-in and hard packed, so as to prevent the possibility of pieces of rock
-or other material falling on to the top of the arch. The neglect of
-this precaution may lead to a casualty years after the tunnel has been
-completed.</p>
-
-<p>It would be impossible to over-rate the importance of a constant
-faithful supervision of the building of the lining, especially the
-arching. The work has to be carried on by workmen in cramped
-positions, with imperfect light, and surrounded by all kinds of
-obstacles and inconveniences, and unless a detailed inspection be
-rigidly maintained, a carelessness in the selection of the materials,
-and a laxity in the workmanship, will be the inevitable result.</p>
-
-<p><a href="#fig204">Figs. 204</a> to <a href="#fig212">219</a> are sections of tunnels which have been constructed
-for double and single line railways. The sections give the normal form
-and dimensions adopted in each case, although there may have been many
-portions of the work where unfavourable or treacherous material
-necessitated an increase in the thickness of the side walls, or of the
-arching, or of both. The types vary in accordance with the opinions of
-the designers as to the most suitable section for the purpose, and
-range from the comparatively thin lining and vertical side walls shown
-on <a href="#fig204">Fig. 207</a>, to the almost circular form and very thick lining shown
-on <a href="#fig212">Fig. 216</a>. The latter is the section which experience has proved to
-be the best to sustain the enormous all-round pressure exerted by
-certain descriptions of swelling clay.</p>
-
-<p>Careful judgment will be required to decide which parts of a rock
-tunnel may be left unlined. The apparently solid-looking portions are
-oftentimes deceptive, and numbers of instances are on record of large
-pieces of rock falling down in tunnels which for many years had been
-considered as thoroughly secure. Where there is any doubt it is better
-and safer to put in a lining, even if only to the extent of an arching
-springing from side walls of solid rock, as shown on <a href="#fig204">Fig. 206</a>. A
-moderate additional expenditure at the time of construction may
-prevent a serious catastrophe afterwards.</p>
-
-<div class="figcenter">
- <a name="fig220"></a>
- <img src="images/i177.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 220 through 223"
- title="Figures 220 through 223"
- />
-</div>
-
-<p>The faces or entrances to tunnels may be constructed with
-<!--189.png--><!--190.png--><a name="Page_178" id="Page_178"></a><span class="pagenum">[Pg 178]</span>
-curved wing
-walls, as in <a href="#fig220">Fig. 220</a>, or with straight wing walls, as in <a href="#fig220">Figs. 221,
-222, and 223</a>. Where the approach cutting is in rock, the latter form
-is generally adopted.</p>
-
-<p>It would be misleading to put down any average price for tunnel-work.
-So much depends upon the locality, the description of material to be
-excavated, the cost of masonry or brickwork, and the cost of labour.
-Added to these come the unforeseen troubles of slips and water-laden
-strata, creating difficulties which baffle the miners for a time, and
-add enormously to the expenditure. Some tunnels for double line have
-been constructed in good ground, and under favourable circumstances as
-to building materials and labour, for as low as £32 per lineal yard;
-while others, carried out under adverse conditions, have cost as much
-as £150 per lineal yard. A medium somewhere between the two should
-represent the cost of tunnel-work through ground which does not
-present any special difficulty. At the same time it must be borne in
-mind that simple tunnelling which can be done in one locality for £50
-or £60 per lineal yard, would be increased 20, 30, or 40 per cent. in
-another, where building material for the lining is scarce and
-expensive.</p>
-
-<p>Tunnel-work abroad will generally cost more than the same work at
-home. The native labourers may perhaps be procured at low rates, but
-the skilled workmen must be brought from a distance, and will obtain
-high wages.</p>
-
-<p>Another form of tunnel-work, generally termed the covered-way system,
-is frequently adopted in towns and places where land and space are
-very valuable. This method consists in the excavating and removing of
-earthwork to admit of the building of the side walls and arching of a
-suitable tunnel-way, and then filling in over the top to a depth of
-three or four feet, or up to the level of the original surface of the
-ground. This work may be carried out by either removing the entire
-width of the earthwork before the commencement of any building
-operations, or by first forming two deep, well-shored trenches, in
-which to build the side walls up to about arch-springing. In bad
-ground the latter arrangement has the advantage, as the shoring and
-strutting to hold up the sliding material is limited to the widths of
-the two narrow trenches, and the centre block of earthwork is left
-untouched as a support to the strutting. When the side walls have been
-built sufficiently high the upper portion of the centre block of
-earthwork can be removed to allow of the
-<!--191.png--><a name="Page_179" id="Page_179"></a><span class="pagenum">[Pg 179]</span>
-erection of centering and
-building of the arching, and afterwards the remaining portion of
-earthwork can be removed at convenience. In this manner a tunnel-way
-may be constructed under streets, gardens, and even under buildings.
-Being nearly all done in the open, the work is more under control than
-in an ordinary tunnel, but it is usually very costly. Temporary or
-diverted roads must be arranged; the excavated material must generally
-all be removed by carts, sometimes to long distances; and provision
-must be made for diverting the network of sewers, gas, and water pipes
-which are intercepted along the route.</p>
-
-<p><a href="#fig224">Fig. 224</a> is a sketch of covered-way with brick arching. <a href="#fig224">Fig. 225</a>
-illustrates another type where cast-iron girders and jack-arches of
-brickwork were introduced on account of the small headway. In soft
-yielding clay it is necessary to construct strong inverts, as
-indicated in the sketches. Recesses for the platelayers should be
-provided every ten or fifteen yards.</p>
-
-<p>The above systems of covered-way were largely adopted in the
-construction of the underground portions of the Metropolitan Railway
-and District Railways in and around London.</p>
-
-<div class="figcenter">
- <a name="fig224"></a>
- <img src="images/i180.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 224 through 226"
- title="Figures 224 through 226"
- />
-</div>
-
-<p>In addition to the ordinary type of tunnel formed by first excavating
-the material and then lining the opening with brickwork or masonry,
-tunnels of moderate size have been constructed of cast-iron tubes,
-similar in section to <a href="#fig224">Fig. 226</a>. The tubes were cast in short segments,
-bolted together inside, the outer circumference, or surface in contact
-with the earth or clay, being left free from projections of any kind.
-By making the segments with bolt-holes exact to template, they were
-readily fitted together in the work, and a thin layer of suitable
-packing material placed between the bolting-flanges sufficed to render
-the tubes water-tight. The tunnelling was carried on by means of a
-short length of slightly larger tube, or cap, made of plate-iron or
-steel, which fitted over the leading end of the main tube. The front
-end of this cap was made very strong, and provided with doors through
-which the miners could work. A series of hydraulic presses attached to
-the cap were brought to bear on the bolting-flange of the last
-completed ring, and as the excavated matter was removed by the miners
-from the front the cap was forced forward by the hydraulic presses,
-and another ring of cast-iron segments inserted. On the City and South
-London Railway, constructed on the above system, the small annular
-space formed round the cast-iron tube by the operation
-<!--192.png--><!--193.png--><a name="Page_181" id="Page_181"></a><span class="pagenum">[Pg 181]</span>
-of the sliding
-cap was filled in with cement grouting by means of an ingenious
-machine designed for the purpose.</p>
-
-<p>Large tunnels under rivers or tidal estuaries must each be dealt with
-according to the particular circumstances of depth below stream-bed,
-material to be cut through, length of tunnel, and gradient. The chief
-obstacle to be contended against in so much of the river tunnel-work
-is the large volume of water which pours into the workings through
-fissures in rock or seams of gravel and sand, necessitating the
-constant use of most powerful pumps. In ordinary land tunnels the
-gradients are generally laid out to fall towards one or both
-entrances, and any water finding its way into the excavations may be
-led away to the entrances by drains or pipes. On the other hand, in a
-river tunnel the gradients generally fall away from the entrances down
-towards the centre of the river, and all water coming in must be
-pumped out and raised up to at least the level of the river. In places
-where the water comes streaming in from many points, any failure or
-stoppage of the pumps would place the lives of the miners, and the
-security of the work itself, in great jeopardy. Iron shields, or
-protection chambers for the miners advancing the excavation, have been
-used with great success in carrying on work through loose wet strata
-which appeared to defy all other means of progress. Solid rock, chalk,
-or compact clay, may present no difficulty so far as they go, but a
-continued dip in the gradient, or a line of fault, may suddenly change
-the entire course of operations, and require the immediate use of the
-most powerful pumping machinery and protective appliances. The special
-features of each case will demand special precautions, and the
-judgment and inventive powers of the engineer will be severely tested
-in coping with the difficulties with which he is surrounded.</p>
-</div><!--end chapter two-->
-
-<div class="chapter">
-<!--194.png--><a name="Page_182" id="Page_182"></a><span class="pagenum">[Pg 182]</span>
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER III.</h3>
-
-<p class="center smaller">Permanent way&mdash;Rails&mdash;Sleepers&mdash;Fastenings&mdash;and Permanent way laying.</p>
-
-<p class="p2"><strong>Rails.</strong>&mdash;Accustomed as we now are to the substantial character of the
-permanent way of our railways, we can scarcely realize that in the
-earlier examples the rails or tram-plates were made of wood. The first
-lines of which we find any record were those constructed to facilitate
-the conveyance of coal, iron ore, stone, slate, or other heavy
-materials to shipping ports or points of distribution. Speed was a
-matter of little importance, the principal object being to introduce a
-distinct surface or roadway which would allow a heavier load to be
-hauled without increasing the hauling power. As a heavily loaded
-wheelbarrow, difficult to move on an ordinary road, can be readily
-wheeled along a wooden plank, so it may have been inferred that strong
-timber, laid in parallel lines and level and even on the upper
-surface, would form a track, or roadway, presenting far less
-resistance than the ordinary gravelled or paved roads.</p>
-
-<p>The wooden tramway was the first improvement over the ordinary road.
-The idea once originated, various types were soon introduced, and the
-sketch shown in <a href="#fig227">Fig. 227</a> illustrates one which appears to have been
-early suggested and largely adopted. Wooden cross-sleepers, <strong>A</strong>, <strong>A</strong>,
-were placed at convenient spaces, and on the top of these strong
-timber planks or beams, <strong>B</strong>, <strong>B</strong>, were spiked at proper distances to
-suit the wheels of the waggons or four-wheel trucks, which had flat
-tyres like ordinary carts. The spaces between the sleepers were filled
-in with gravel or broken stone to form a roadway or hauling path for
-the horses. A little later <em>double rails</em> were introduced, by placing
-a second or upper timber on the top of the lower one, as in <a href="#fig227">Fig. 228</a>.</p>
-
-<div class="figcenter">
- <a name="fig227"></a>
- <img src="images/i183.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 227 through 232"
- title="Figure  227 through 232"
- />
-</div>
-
-<p>This double rail arrangement not only strengthened the framework, but
-by increasing the height allowed a greater
-<!--195.png--><!--196.png--><a name="Page_184" id="Page_184"></a><span class="pagenum">[Pg 184]</span>
-quantity of suitable
-material to be placed over the sleepers to protect them from wear by
-the horses’ feet. It can be easily understood that a wooden tramway
-could not be very durable. It would be affected by the sun, rain, and
-snow, and particles of sand and gravel thrown on to the tram beams
-from the hauling path would hasten the abrading or wearing away of the
-soft portions of the timber into hollows, leaving the hard knots
-standing out as projections. The uneven surface would produce a series
-of blows every time a loaded truck passed along, loosening the pieces
-and rendering the repairs constant and expensive. To obviate the rapid
-wear of the tram-timbers continuous narrow bars of wrought-iron were
-fastened on to the running-surfaces; these in a measure prolonged the
-life of the timbers, but at the same time added to the number of the
-pieces and fastenings to be maintained.</p>
-
-<p>Primitive as this description of road appears to be, it was in use for
-many years in some parts of the United States of America, and even
-after the introduction of the early locomotives; timber was abundant
-and cheap, and iron in any form was costly. These long thin strips of
-iron, placed as in <a href="#fig227">Fig. 232</a>, had a tendency to become unfastened at
-the ends, and to curl up in a very alarming manner, which earned for
-them the soubriquet of <em>snake heads</em>. Although iron was only used to a
-limited extent in the first instance, it was soon found to be a much
-more suitable material for a tram-path than the best timber. As a next
-progressive step we find that the tram-plates were made entirely of
-iron, of full width for the wheel-tyres, and with a guiding flange to
-keep the wheels on the proper track. In some cases the guiding flanges
-were placed inside the wheels, as in <a href="#fig227">Figs. 229 and 230</a>, and in others
-outside, as in <a href="#fig227">Fig. 231</a>. With the former plan a thicker covering of
-gravel or broken stones could be laid down to protect the sleepers
-under the horse-path.</p>
-
-<p>These solid tram-plates were made of cast-iron, that metal being
-considered the most convenient for manufacture and the least liable to
-suffer loss from rust and oxidization. Another advantage of the
-cast-iron was that broken tram-plates could be melted down and recast
-at a moderate cost.</p>
-
-<p>Long lengths of these cast-iron plate tramways were laid down in this
-country and abroad, and short portions of some of them remain in
-existence even to the present day. They
-<!--197.png--><a name="Page_185" id="Page_185"></a><span class="pagenum">[Pg 185]</span>
-were of immense service for
-the transportation of heavy materials, and without their adventitious
-aid many valuable collieries and quarries must long have remained idle
-and undeveloped. In thus providing a level, smooth, and comparatively
-durable wheel-track for the waggons, these tramways became the fitting
-pioneers of the great railway system which was to follow.</p>
-
-<p>Notwithstanding the great superiority of the cast-iron plates as
-compared with the former timber beams, much inconvenience was still
-caused by gravel and dirt falling on to the wheel-track and seriously
-impeding the haulage of the waggons. To overcome this difficulty the
-next step taken was to remove the guiding flange from the tram-plate
-and transfer it to the wheel, thus developing and introducing the
-original flanged wheel. This was a most important step, and paved the
-way for other improvements. The rails, or <em>edge rails</em>, as they were
-at first called, were made sufficiently high to allow ample space for
-the wheel-flanges to clear the ground, and were secured to cast-iron
-chairs placed on wooden cross-sleepers, or in some cases to stone
-blocks, as shown in <a href="#fig227">Figs. 233, 234, and 235</a>. The narrow top of rail,
-and its height above the horse-path, effectually prevented the
-lodgment of gravel or dirt, and the flanges on the wheels ensured a
-more even course. From the irregular and easily choked-up tram-plate,
-the system changed to the clean rail and properly defined track.
-Waggons could be hauled with greater freedom, and with less wear and
-tear to themselves and to the roadway.</p>
-
-<p>At this time the use of the steam-engine was becoming more general,
-and a fine field was opened out for its application as a motive-power
-on the tramways. Stationary engines, or <em>winding engines</em>, as they
-were called, were first employed to haul the trucks by means of long
-ropes passed round revolving drums, and supported at intervals by
-grooved pulleys placed between the rails at suitable distances. In
-this way fair loads could be conveyed, and at moderate cost; but the
-system was found to be only suitable for short distances, and it had
-the great drawback that horses or other motive-power were still
-necessary for sorting or distributing the trucks before and after
-their transit by rope haulage.</p>
-
-<p>The next great advance was to place the steam-engine on wheels, to
-enable it to haul and accompany the trucks. Crude
-<!--198.png--><a name="Page_186" id="Page_186"></a><span class="pagenum">[Pg 186]</span>
-and imperfect as the
-primitive locomotives must have been, a very short trial of
-them served to show that the rails of cast-iron then in use were
-totally unfitted to form a trackway for the newly invented machines.
-The short fish-bellied cast-iron rails were made in lengths merely to
-extend from chair to chair; they possessed little or no continuity,
-and from the inherent brittleness of the material they were constantly
-breaking and giving way under the increased weights imposed upon them.
-It became necessary to adopt a more reliable material, and attention
-was naturally turned to forged or wrought iron. The suggestion once
-made was promptly responded to by the iron makers. Special machinery
-was designed and constructed, and very soon wrought-iron rails were
-manufactured in large quantities. At first they were made very similar
-in section to the fish-belly cast-iron rails, but in lengths to extend
-over three or four sleepers. The increased length gave greater
-stability to the road, and permitted an increase of speed. The
-manifest superiority of the wrought-iron rails led to their universal
-adoption, and a great impetus was thus given to their manufacture.
-Improvements were made in the machinery for rolling, and more care was
-bestowed in the working of the iron. Changes were made in the section
-of the rails; the fish-belly form was discarded, and a double-head
-type was introduced to give more lateral stiffness. At this period in
-its history the capabilities of the <em>iron road</em> began to be more fully
-recognized, and the supporters of the system foresaw a great future
-success, both for the conveyance of passengers as well as goods.
-Hitherto the tramroads or railroads had been used for minerals and
-merchandize only, but it was now claimed that on a carefully
-constructed line, and with improved locomotives and rolling-stock, it
-would be possible to convey passengers more conveniently and rapidly
-than by any other method.</p>
-
-<div class="figcenter">
- <a name="fig236"></a>
- <img src="images/i187.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 236 through 258"
- title="Figures 236 through 258"
- />
-</div>
-
-<p>Inventive minds were at work to accomplish so desirable an object, and
-public enterprise was forthcoming to provide funds for the purpose.
-The successful working of the first passenger line formed the dawn of
-a new era in travelling, and similar lines were soon projected for
-other places. The wrought-iron rails in use at this time were
-generally of a double head form, and rarely exceeded 12 or 15 feet in
-length. They were held by wooden pegs in cast-iron chairs, which were
-secured to
-<!--199.png--><!--200.png--><a name="Page_188" id="Page_188"></a><span class="pagenum">[Pg 188]</span>
-timber cross-sleepers or stone blocks, as shown in <a href="#fig227">Figs.
-234 and 235</a>.</p>
-
-<p>They were light in section, and it is stated that the first rails on
-the Liverpool and Manchester Railway weighed only 33 lbs. per yard.</p>
-
-<p>The railway system spread rapidly, and the constantly increasing
-traffic of all kinds soon necessitated heavier rails. Various sections
-were devised and tried on different lines, one of the main objects in
-view being to obtain a steady road for the increasing speeds, as well
-as one of durability. Some of these sections are shown in <a href="#fig236">Figs. 236 to
-258</a>.</p>
-
-<p>Sections <a href="#fig236">236 to 248</a> all required chairs to attach them to the
-sleepers. The flange rails, <a href="#fig236">249 to 253</a>, and bridge rails, <a href="#fig236">254 to 256</a>,
-also rail <a href="#fig236">257</a>, were designed to rest direct upon the sleepers without
-the necessity of chairs; and the Barlow rail, <a href="#fig236">258</a>, with its great
-width of 11 or 12 inches, was intended to be used without sleepers of
-any kind, the gauge being secured by means of angle iron tie-bars.</p>
-
-<p>Rails were rolled heavier and longer, and more care was bestowed on
-the fastenings; but, notwithstanding these improvements, the
-rail-joints still continued to be the weak point in the road. Even
-with an extra large joint-chair and stout wooden key, there was much
-vertical play at the ends of the rails, producing objectionable noise
-and vibration in the running, and acting detrimentally on all the
-fastenings. The introduction of fish-plates at the rail-joints, as
-shown in <a href="#fig259">Fig. 259</a>, effected an improvement which cannot be overrated,
-as by their adoption such security, speed, and smoothness became
-attainable as were not before possible. With a pair of simple rolled
-wrought-iron fish-plates, or splices, and four bolts&mdash;two through the
-end of each rail&mdash;a better, smoother, and more effectual joint was
-obtained than had ever been produced by the heavy cast-iron
-joint-chairs. The system of fishing, or splicing, was at once admitted
-to be the simplest and most direct method of joining the rails; and,
-although minor detailed improvements have since been made, the
-arrangement, as a principle, has never been superseded. Many miles of
-fished rails were laid down with a chair, or support, placed
-immediately under the joint, forming the method termed the supported
-fish-joint; but experience proved that this mode of application did
-not give such a good result as the suspended fish-joint, and the
-latter plan has now been adopted on almost all railways.</p>
-
-<div class="figcenter">
-<!--201.png--><a name="Page_189" id="Page_189"></a><span class="pagenum">[Pg 189]</span>
- <a name="fig259"></a>
- <img src="images/i189.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 259 through 272"
- title="Figures 259 through 272"
- />
-</div>
-
-<p><!--202.png--><a name="Page_190" id="Page_190"></a><span class="pagenum">[Pg 190]</span>
-The experience obtained year after year in the wear of rails under
-heavy traffic, led to continued improvements both in the method of
-rolling and in the selection of the iron to form the rail-pile; one
-description of iron was found more suitable for the head, or running
-surface, and another for the vertical web; but, even with the best
-machinery and most carefully assorted materials, high-class
-wrought-iron rails were liable to lamination, and long thin strips of
-iron became detached from the upper, or wearing, surface. The rail was
-composed of many layers of iron, and it was not always possible to
-ensure that they were all thoroughly welded, or incorporated together.
-As early as 1854 a few experimental solid steel rails were laid down
-on some of the principal railways, and gave excellent results as to
-evenness of wear and durability, but their cost of manufacture
-rendered their extended use almost prohibitory.</p>
-
-<p>Compound rails of steel and wrought-iron, as in <a href="#fig259">Fig. 260</a>, were also
-tried on several railways, but the practical results were not such as
-to lead to a very extended adoption. In preparing the <em>pile</em> for a
-compound rail, suitable wrought-iron bars were placed to form the
-lower member or flange, the web, and part of the head, and a slab of
-steel was placed on the top to form the upper portion of head, or
-wearing surface of the rail. It was intended that in the process of
-rolling these distinct layers were to be incorporated together, to
-form the section shown in <a href="#fig259">Fig. 260</a>. Doubtless many good wearing rails
-were manufactured on this system, but the inherent difference of the
-two materials, steel and iron, rendered it very difficult to ensure
-such uniform incorporation as would withstand the constant pounding
-under heavy, fast traffic. It was not until some years later that the
-process of the Bessemer Converter was discovered and perfected, by
-means of which steel can be produced in large quantities far more
-rapidly and at much less cost than by any other method hitherto
-adopted. The introduction of this process for making steel caused a
-complete revolution in the material for rails. Steel which had
-previously been excluded on account of its cost, could now be supplied
-at a moderate price, and, from its compact and homogeneous character,
-promised a very much longer wearing life than the best wrought-iron
-rails that had ever been rolled. Experience has shown that these
-promises have been fully verified; wrought-iron rails are things of
-the past, steel rails have taken their place, and can now be
-<!--203.png--><a name="Page_191" id="Page_191"></a><span class="pagenum">[Pg 191]</span>
-purchased
-at a less price per ton than the iron rails of twenty years ago.</p>
-
-<p>It is interesting to note that out of the many varied sections that
-have been designed, some of which are shown in the sketches described,
-only two have practically survived&mdash;the bullhead rail and the flange
-rail. The bull-head rail, <a href="#fig259">Fig. 261</a>, has grown out of the original
-double-head rail, which had both the top and bottom members made to
-the same section and weight, with the object that, when the upper
-table had become so much worn as to be unfit for further use, then the
-rail could be turned, and the other table, or head, brought into
-service. Experience, however, proved that turned rails formed a most
-uneven and unsatisfactory road, the long contact with the cast-iron
-chairs resulted in serious indentations at the rail-seats, rendering
-the rails totally unfitted for smooth running. In practice, therefore,
-it has been found better to restrict the running wear to one head
-only, and to give increased sectional area to that head, and, at the
-same time to diminish the sectional area of the lower member to a
-corresponding extent, but to retain the same width, so as to obtain a
-full bearing surface on the cast-iron chair. Steel bull-head rails are
-now adopted on nearly all the principal lines at home, and on several
-of the leading lines abroad.</p>
-
-<p>The flange rail, <a href="#fig259">Fig. 265</a>, was designed to give a broad, direct
-bearing on the sleepers, and thus avoid the necessity of using chairs.
-Rails of this section have been laid down on many of our lines at
-home, and are very largely used on the Continent, in the United States
-of America, and in our colonies generally. This section is, also,
-nearly always adopted for narrow-gauge railways. Having fewer parts,
-it makes a cheaper road than the bull-head rail, but is not considered
-so strong or suitable for heavy and fast traffic. Comparing the two
-rails shown in <a href="#fig259">Figs. 261 and 265</a>, each having exactly the same size
-and sectional area in the head, it will be seen that there is more
-material in the lower member, or flange, of the one rail than there is
-in the lower member of the other; the weight per lineal yard being 79
-lbs. for the former and 75 lbs. for the latter. But this small excess
-in the weight and cost of the flange rail falls very short of the cost
-of the cast-iron chairs and wooden keys necessary for the bull-head
-rail.</p>
-
-<p>Up to the years 1870-1875, it was the common practice to make the top,
-or wearing surface of the rail, comparatively
-<!--204.png--><a name="Page_192" id="Page_192"></a><span class="pagenum">[Pg 192]</span>
-round, as shown on the
-typical sections, <a href="#fig259">Figs. 263 and 267</a>. The effect of this sharp-curved
-outline was to limit the first wearing, or contact surface to a narrow
-strip along the head of rail, causing a tendency to groove or form
-hollows in the treads of the wheel-tyres. As the rail wore down, the
-upper surface assumed a much flatter curve, more closely assimilated
-to the section of the wheel-tyre, and giving better results for
-regular wear under heavy traffic. Profiting by this experience, the
-rails of the present day are made much flatter on the head than they
-were formerly, as will be noted from the sections shown on <a href="#fig259">Figs. 261,
-266, and 269</a>, which represent types of rails now actually in use on
-some of the principal railways.</p>
-
-<p>In designing a rail for any given line, the section and weight of the
-rail must necessarily be influenced by the weight of the rolling-stock
-passing over it, and the amount of the traffic it has to sustain.</p>
-
-<p>The engine, being the heaviest vehicle in the train, will give the
-measure of the greatest weight on one pair of wheels. Engines vary
-considerably on different lines, ranging from ten tons to eighteen
-tons or more on one pair of driving-wheels, according to the
-description of work to be performed.</p>
-
-<p>Very often secondary or branch lines, with comparatively light
-traffic, have steep gradients, necessitating engines as heavy as on a
-main trunk line; but the number of trains on the former may not exceed
-twenty per day, while on the latter they may amount to one hundred and
-fifty or two hundred. It is evident that the rail which would last for
-very many years under the small traffic, would have a very short life
-under the frequent traffic. Hence the reason why it is found expedient
-to give a large increase of material in the heads of rails carrying
-the heavy, constant train service of many of our main lines.</p>
-
-<p><a href="#fig259">Figs. 261, 262, and 263</a> are sections of rails in use on lines having
-heavy engines and fast trains, but with a comparatively small daily
-train service, and <a href="#fig259">Figs. 264, 266, 267, and 268</a> are sections of rails
-carrying the heavy, fast, and incessant traffic of some of our leading
-lines.</p>
-
-<p>On lines having small traffic, slow speeds, easy gradients, and
-comparatively light engines, a reduced section of rail may be adopted;
-but in doing so it is well to allow for any probable future
-development of traffic which might cause the introduction of heavier
-engines.</p>
-
-<p><!--205.png--><a name="Page_193" id="Page_193"></a><span class="pagenum">[Pg 193]</span>
-<a href="#fig259">Figs. 269 to 272</a> show sections of rails varying from 72 to 60 lbs. per
-yard, also a section of a 45-lb. steel flange-rail, much used on
-3-foot <a name="gauge2"></a>narrow-gauge railways.</p>
-
-<p>Valuable and interesting statistics have from time to time been
-recorded, with a view to ascertain the average life of a steel rail,
-by obtaining the number of million tons of train load which it would
-sustain before it became worn down to such an extent as to be no
-longer of service on the line. It will be readily understood that the
-rate of wear of a steel rail will depend not only on the weight and
-section of the rail itself, but on the class of rolling-stock, and the
-description of traffic it has to carry. It will also be largely
-affected by the circumstances of whether the line is on a level or on
-an incline.</p>
-
-<p>The writer has had careful measurement taken of the wear of the steel
-flange-rail (<a href="#fig259">Fig. 265</a>), 79 lbs. per yard, and the result shows that
-with a traffic not exceeding twenty-four goods and passenger trains
-per day, one-tenth of an inch was worn off the top of the rail in ten
-years on the comparatively level portions of the line; but that the
-same amount of one-tenth of an inch was worn off in six years by the
-same traffic, on the same district of the line, in places where the
-gradients varied from 1 in 100 to 1 in 70. The heavy pounding of the
-engines, and the working of the <a name="brakes"></a>brakes tend very materially to shorten
-the life of the rails on the inclines.</p>
-
-<p>As now made, the steel rails manufactured under the converter process
-exhibit great similarity in the analysis of their component parts; at
-the same time it is well known that a slight preponderance or
-reduction of one or more of the constituents will result in making the
-steel hard or soft. The following statement gives the analysis of
-twelve steel rails, six of which were classed as <em>hard</em> steel, and six
-as <em>soft</em> <span style="white-space:nowrap;">steel:&mdash;</span></p>
-
-<p class="p2 center break"><a name="hardsteel"></a><span class="sc">Hard Steel.&mdash;Analysis of Six Steel Rails which broke either in Testing
-or in Line.</span></p>
-
-<div class="nothandheld">
-<table summary="Analysis of Rails that broke">
-
-<tr><td class="t b"></td><td class="center l t b"><strong>1.</strong></td><td class="center l t b"><strong>2.</strong></td><td class="center l t b"><strong>3.</strong></td><td class="center l t b"><strong>4.</strong></td><td class="center l t b"><strong>5.</strong></td><td class="center l t b"><strong>6.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·47</td><td class="right l">0·51</td><td class="right l">0·56</td><td class="right l">0·43</td><td class="right l">0·47<span class="hide">0</span></td><td class="right l">0·54<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·09</td><td class="right l">0·08</td><td class="right l">0·08</td><td class="right l">0·09</td><td class="right l">0·095</td><td class="right l">0·121</td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·06</td><td class="right l">0·06</td><td class="right l"> 0·06</td><td class="right l">0·06</td><td class="right l">0·054</td><td class="right l">0·056</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·07</td><td class="right l">0·06</td><td class="right l">0·06</td><td class="right l">0·08</td><td class="right l">0·08<span class="hide">0</span></td><td class="right l">0·057</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">1·23</td><td class="right l">1·10</td><td class="right l">0·90</td><td class="right l">1·23</td><td class="right l">1·15<span class="hide">0</span></td><td class="right l">1·26<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·08</td><td class="right l b">98·19</td><td class="right l b">98·34</td><td class="right b l">98·11</td><td class="right b l">98·151</td><td class="right b l">97·966</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td>
-</tr>
-</table>
-</div>
-
-<div class="handheld">
-<table summary="Analysis of Rails that broke, part 1">
-
-<tr><td class="t b"></td><td class="center l t b"><strong>1.</strong></td><td class="center l t b"><strong>2.</strong></td><td class="center l t b"><strong>3.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·47</td><td class="right l">0·51</td><td class="right l">0·56</td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·09</td><td class="right l">0·08</td><td class="right l">0·08</td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·06</td><td class="right l">0·06</td><td class="right l"> 0·06</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·07</td><td class="right l">0·06</td><td class="right l">0·06</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">1·23</td><td class="right l">1·10</td><td class="right l">0·90</td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·08</td><td class="right l b">98·19</td><td class="right l b">98·34</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td>
-</tr>
-</table>
-
-<table summary="Analysis of Rails that broke, part 2">
-
-<tr><td class="t b"></td><td class="center l t b"><strong>4.</strong></td><td class="center l t b"><strong>5.</strong></td><td class="center l t b"><strong>6.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·43</td><td class="right l">0·47<span class="hide">0</span></td><td class="right l">0·54<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·09</td><td class="right l">0·095</td><td class="right l">0·121</td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·06</td><td class="right l">0·054</td><td class="right l">0·056</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·08</td><td class="right l">0·08<span class="hide">0</span></td><td class="right l">0·057</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">1·23</td><td class="right l">1·15<span class="hide">0</span></td><td class="right l">1·26<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·11</td><td class="right b l">98·151</td><td class="right b l">97·966</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·00</td><td class="right l b">100·00</td><td class="right l b">100·00</td>
-</tr>
-</table>
-</div><!--end split tables for handhelds-->
-
-<!--206.png--><a name="Page_194" id="Page_194"></a><span class="pagenum">[Pg 194]</span>
-
-<p class="p2 center break"><a name="softsteel"></a><span class="sc">Soft Steel.&mdash;Analysis of Six Steel Rails which stood the Test well, and
-bent freely without showing any Sign of Fracture.</span></p>
-
-<div class="nothandheld">
-<table summary="Analysis of Rails that bent freely">
-<tr><td class="t b"></td><td class="center l t b"><strong>1.</strong></td><td class="center l t b"><strong>2.</strong></td><td class="center l t b"><strong>3.</strong></td><td class="center l t b"><strong>4.</strong></td><td class="center l t b"><strong>5.</strong></td><td class="center l t b"><strong>6.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·35<span class="hide">0</span></td><td class="right l">0·39<span class="hide">0</span></td><td class="right l">0·37<span class="hide">0</span></td><td class="right l">0·34<span class="hide">0</span></td><td class="right l">0·35<span class="hide">0</span></td><td class="right l">0·250</td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·06<span class="hide">0</span></td><td class="right l">0·07<span class="hide">0</span></td><td class="right l"> 0·07<span class="hide">0</span></td><td class="right l">0·08<span class="hide">0</span></td><td class="right l">0·07<span class="hide">0</span></td><td class="right l">0·069</td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·062</td><td class="right l">0·061</td><td class="right l">0·062</td><td class="right l">0·061</td><td class="right l">0·061</td><td class="right l">0·046</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·061</td><td class="right l">0·061</td><td class="right l">0·061</td><td class="right l">0·063</td><td class="right l">0·062</td><td class="right l">0·058</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">0·870</td><td class="right l">0·875</td><td class="right l">0·866</td><td class="right l">0·864</td><td class="right l">0·800</td><td class="right l">0·636</td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·597</td><td class="right b l">98·543</td><td class="right l b">98·571</td><td class="right b l">98·592</td><td class="right b l">98·657</td><td class="right b l">98·941</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td>
-</tr>
-</table>
-</div>
-
-<div class="handheld">
-<table summary="Analysis of Rails that bent freely, part 1">
-<tr><td class="t b"></td><td class="center l t b"><strong>1.</strong></td><td class="center l t b"><strong>2.</strong></td><td class="center l t b"><strong>3.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·35<span class="hide">0</span></td><td class="right l">0·39<span class="hide">0</span></td><td class="right l">0·37<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·06<span class="hide">0</span></td><td class="right l">0·07<span class="hide">0</span></td><td class="right l"> 0·07<span class="hide">0</span></td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·062</td><td class="right l">0·061</td><td class="right l">0·062</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·061</td><td class="right l">0·061</td><td class="right l">0·061</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">0·870</td><td class="right l">0·875</td><td class="right l">0·866</td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·597</td><td class="right b l">98·543</td><td class="right l b">98·571</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td>
-</tr>
-</table>
-
-<table summary="Analysis of Rails that bent freely, part 2">
-<tr><td class="t b"></td><td class="center l t b"><strong>4.</strong></td><td class="center l t b"><strong>5.</strong></td><td class="center l t b"><strong>6.</strong></td>
-</tr>
-<tr><td class="left">&emsp;Carbon</td><td class="right l">0·34<span class="hide">0</span></td><td class="right l">0·35<span class="hide">0</span></td><td class="right l">0·250</td>
-</tr>
-<tr><td class="left">&emsp;Silicon</td><td class="right l">0·08<span class="hide">0</span></td><td class="right l">0·07<span class="hide">0</span></td><td class="right l">0·069</td>
-</tr>
-<tr><td class="left">&emsp;Sulphur</td><td class="right l">0·061</td><td class="right l">0·061</td><td class="right l">0·046</td>
-</tr>
-<tr><td class="left">&emsp;Phosphorus</td><td class="right l">0·063</td><td class="right l">0·062</td><td class="right l">0·058</td>
-</tr>
-<tr><td class="left">&emsp;Manganese</td><td class="right l">0·864</td><td class="right l">0·800</td><td class="right l">0·636</td>
-</tr>
-<tr><td class="left">&emsp;Iron</td><td class="right b l">98·592</td><td class="right b l">98·657</td><td class="right b l">98·941</td>
-</tr>
-<tr><td class="b"></td><td class="right l b">100·000</td><td class="right l b">100·000</td><td class="right l b">100·000</td>
-</tr>
-</table>
-</div><!--end split tables for handhelds-->
-
-<p>Many rails which have been broken in the line under traffic have been
-analyzed, and proved to be hard steel; while others, which have been
-bent into all sorts of shapes, but not broken during accidents or
-derailments, have also been tested, and proved to be of soft steel.</p>
-
-<p>Some engineers are advocates for a hard steel rail, and claim for it
-greater durability and longer wear; but even supposing such hard rail
-should possess a slight superiority over the soft rail, it is well to
-consider whether such assumed advantage is not obtained at the risk of
-incurring greater liability to fracture. It must be borne in mind that
-a rail, once placed in the road, is exposed to all the changes of
-temperature from heat to frost, and has frequently to sustain
-increased strains arising from loose sleepers, where the gravel or
-ballast has been disturbed during heavy rains.</p>
-
-<p>When writing a specification for steel rails, it is usual to state the
-number of tons per square inch in tensile strain which the steel must
-be able to sustain without fracture, and also to stipulate that some
-of the rails will be tested by the falling-weight test. In the latter
-test a rail is placed, say at 3 feet bearings, and in a similar
-position to what it would occupy in the road, and a weight of eighteen
-hundredweight, or one ton or more, according to section of rail, is
-allowed to fall from a height of 9 or 10 feet, on to the rail, at the
-centre between the bearings. With three blows from the given height,
-the rail must not bend or deflect more than a specified amount. The
-falling-weight test is, perhaps, rather a rough and ready one; but it
-is always reassuring to prove that the rails will withstand such a
-severe ordeal, as it must be a very exceptional circumstance in the
-routine of railway working which will produce a blow or shock
-<!--207.png--><a name="Page_195" id="Page_195"></a><span class="pagenum">[Pg 195]</span>
-equal
-in effect to the falling-weight test. The rails form such an important
-part of the trackway, almost the very basis on which the traffic has
-to depend for its safety, that, apart from the question of wear, no
-effort should be spared to ensure their thorough soundness and
-efficiency.</p>
-
-<p>In modern practice rails are generally used in lengths varying from 25
-feet to 30 feet. There is no difficulty in making them longer; but any
-excess over the above lengths is found to be inconvenient for
-transport, for handling in the line, and for making the necessary
-allowance for contraction and expansion at the joints. Steel rails are
-generally marked on the vertical web with the initials of the railway
-company, the name of the manufacturer, and the year in which they are
-rolled. This is done by cutting out the letters in the last pair of
-rolls through which the rails have to pass before they are completed,
-so that on the rails themselves the letters stand out in raised
-characters, thus: <strong>G.N.R.I.......C. CAMMELL &amp; C<sup>o</sup> 1896</strong>. In this
-manner the rails always carry for reference the name of maker and
-date.</p>
-
-<p>When comparing the relative merits of the flange-rail and
-bull-head-rail permanent way, the question of strength and durability
-must be considered, as well as that of economy. The flange-rail road
-has undoubtedly fewer parts and fastenings, and when the flange is
-wide, the sleepers sound, and the rail securely held down to the
-sleepers, the result is a smooth running road. So long as the rail can
-be maintained in a constant close contact with the wooden sleeper, the
-running is almost noiseless, the jarring on the rails being absorbed
-or taken off by the timber; but so soon as a little space or play
-takes place between the spikes or other fastenings and the upper
-surface of the flange, the rail obtains a certain amount of rise, or
-lift, which comes into action upon the passing of every rolling load,
-producing unsteadiness in the rail and a clattering noise in the
-running. A flange of 5 inches, on a sleeper 10 inches wide, has a
-bearing surface of 50 square inches (assuming the sleeper to be square
-cut, without any wane on the edges), and this area of 50 inches is
-only about half of the bearing surface on the sleeper of an ordinary
-modern cast-iron chair.</p>
-
-<p>Main-line locomotives have weights on the driving-wheels varying from
-16 to 18 and 20 tons. Taking 18 tons as representing a common practice
-for a large express engine, would
-<!--208.png--><a name="Page_196" id="Page_196"></a><span class="pagenum">[Pg 196]</span>
-give 9 tons as the weight imposed on
-each rail by each driving-wheel Assuming this weight to be distributed
-over three sleepers would give a dead weight of 3 tons per sleeper, or
-134 lbs. on every square inch of the 50 square inches of surface, or
-rail-bearing area, on each sleeper, without taking into account the
-effect of the blow or percussion from the rolling load. The presence
-of a loose sleeper throws additional weight on the adjoining sleepers,
-and increases the destructive influence on the timber. The constant
-application of heavy rolling loads on a small bearing area of timber
-crushes and wears away the timber very rapidly. The small bearing
-surface of the flange rail expedites the cutting down into the
-sleeper, and as the rail beds itself further and further into the
-wood, the fastenings must be driven or screwed down to follow the
-flange. Spikes may be driven down, but the further they go they have a
-less thickness of timber for a bed, and therefore a diminished hold.
-Crab bolts are apt to become rusted or ironbound, so that they cannot
-be screwed further, and must then be taken out and replaced with new
-ones. The narrower the flange, the more rapidly does the rail-seat cut
-down to a thickness inconsistent with safety. The sharp edge of the
-flange-rail has a tendency to cut a channel in the spike, and it is
-not at all an unusual occurrence to find strong square shanked
-dog-spikes, which have been thus cut into to the extent of a third or
-even half their thickness. The comparative narrow flange places the
-spikes at great disadvantage in point of leverage for holding down,
-and this weakness is soon made manifest, particularly on curves, where
-additional crab bolts or other devices are rendered necessary to
-counteract the tendency of the rail to rock and tilt over sideways.
-When the head of the rail cannot be kept in its proper position, the
-gauge becomes widened, and an irregular sinuous motion takes place in
-the running of the train. This drawback has been found to be a serious
-matter where light narrow flange rails have been adopted to carry
-comparatively heavy, short wheel-base engines. In some cases
-wrought-iron sole-plates, or even cast-iron bracket-chairs, have been
-introduced to give more bearing surface on the sleeper and increased
-support to the rail, but neither of the two methods give the same
-simple complete hold to the rail that is obtained by the cast-iron
-chair for the bull-head rail.</p>
-
-<p>On the other hand, the modern cast-iron chair for the bull-head
-<!--209.png--><a name="Page_197" id="Page_197"></a><span class="pagenum">[Pg 197]</span>
-rail
-has at least double the bearing surface on the sleeper to that of the
-flange-rail seat, so that under the same circumstances of rolling load
-as above described, the weight of 134 lbs. per square inch would be
-reduced to half, or 67 lbs. The greater length given to the chair
-effectually prevents any rocking action on the part of the rail, and
-reduces to a minimum any lifting action on the spike. A good fitting
-chair&mdash;especially when keyed on the inside&mdash;provides a most effectual
-support to the rail both vertically and laterally, and maintains the
-rail to accurate gauge. By giving proper clearance space at the tops
-of the chair-jaws, a bull-head rail can be taken out by simply driving
-out the wooden keys, and a new rail inserted without in any way
-disturbing the chairs or spikes. To change a flange rail necessitates
-the slackening and removal of a large number of the spikes and crab
-bolts.</p>
-
-<p>As the sleepers under the chair road suffer less from the crushing of
-the timber, they have a much longer life in the line, and remain
-serviceable until they are incapacitated from decay. This is a very
-important item in places where timber sleepers are expensive. The
-steadiness of the chair prolongs the efficiency of the spikes.</p>
-
-<p>As the actual wearing portion of the rail is the head, or wheel
-contact surface, a liberal area&mdash;consistent with the expected
-traffic&mdash;must be given to that part, whether for a bull-head rail or a
-flange rail. By comparing the two sections, <a href="#fig273">Figs. 273 and 274</a>, the one
-for an 85-lb. bull-head rail, and the other for a 100-lb. flange rail,
-it will be seen from the dotted lines that the heads of each rail are
-almost identical, the difference of 15 lbs. being disposed of in the
-flange of the heavier rail. Practically, therefore, we have 15 lbs.
-per yard extra weight of steel in the rail, on the one hand, as
-against the cast-iron chairs and steadier permanent way on the other.</p>
-
-<p>For lines where the traffic is small, weights light, speeds low, and
-economy of construction imperative, the flange-rail permanent way will
-be very suitable.</p>
-
-<p>The writer has had long mileages of each description of permanent way
-under his charge, both at home and abroad, for many years, and the
-result of his experience has shown that, although a fairly good road
-may be made with flange rails, still, for constant, heavy, fast
-traffic, the bull-head rail with cast-iron chairs makes a much
-stronger, more durable, and better permanent way than any flange
-railroad.</p>
-
-<div class="figcenter">
-<!--210.png--><a name="Page_198" id="Page_198"></a><span class="pagenum">[Pg 198]</span>
- <a name="fig273"></a>
- <img src="images/i198.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 273 and 274"
- title="Figures 273 and 274"
- />
-</div>
-
-<p><!--211.png--><a name="Page_199" id="Page_199"></a><span class="pagenum">[Pg 199]</span>
-Briefly summarized, the principal advantages and disadvantages of the
-two kinds of rails stand as <span style="white-space:nowrap;">follows:&mdash;</span></p>
-
-<table summary="advantages and disadvantages of rail types">
-
-<tr><td class="center nobox" colspan="2"><strong>ADVANTAGES.</strong></td>
-</tr>
-
-<tr><td class="center nobox">Bull-head Rail.</td><td class="center nobox">Flange Rail.</td>
-</tr>
-
-<tr><td class="left"><p>Large bearing surface of chair
-upon the sleeper, and greater
-stability of the rail.</p>
-
-<p>Longer life of wooden sleeper.</p>
-
-<p>Impossibility of rail tilting
-over outwards.</p>
-
-<p>Facility for changing a rail
-without disturbing the
-fastenings in the sleepers.</p>
-
-<p>Easier to maintain, owing to
-less disturbing strains on the
-fastenings.</p>
-
-<p>A bull-head rail is more
-readily set or laid to follow
-line of curve.</p>
-
-<p>In most cases the one set of
-chairs will serve for a second
-set of rails.</p>
-
-<p>Perfect straightness of rail:
-it is very rare to find a
-crooked bull-head rail.</p>
-
-<p>Easier to roll, and more
-likely to obtain uniformity of
-steel.</p></td>
-
-<td class="leftex"><p>Fewness of parts, and less
-cost.</p>
-
-<p>Smaller quantity of ballast
-required to cover up the foot
-of rail.</p>
-
-<p>More lateral stiffness than
-the bull-head rail.</p></td>
-</tr>
-
-<tr><td class="center nobox" colspan="2"><strong>DISADVANTAGES.</strong></td>
-</tr>
-
-<tr><td class="center nobox">Bull-head Rail.</td><td class="center nobox">Flange Rail.</td>
-</tr>
-
-<tr><td class="left"><p>Greater cost.</p>
-
-<p>More ballast required to cover
-up the rail.</p>
-
-<p>Less lateral stiffness than
-the flange rail.</p>
-</td>
-<td class="leftex"><p>The small rail-seat area on
-sleeper throws great crushing
-weight on the timber.</p>
-
-<p>Shorter life of wooden
-sleepers from the cutting down
-of rail-seats.</p>
-
-<p>The edge of flange cuts the
-spikes after a few years.</p>
-
-<p>The undulation of the rail
-under trains tends to raise
-the spikes, and causes lateral
-movement in the rails.</p>
-
-<p>More difficult to maintain, in
-consequence of greater
-tendency of the fastenings to
-work loose.</p>
-
-<p>Difficulty in getting flange
-rails straightened laterally.</p>
-
-<p>More difficult to set to
-follow regular line of curves.</p>
-
-<p>More difficult to roll, and
-less likely to obtain
-uniformity of steel.</p></td>
-</tr>
-
-</table>
-
-<p class="p2"><strong>Tramway Rails.</strong>&mdash;Tramways on streets or public roads are now
-universally recognized as important branches of the railway principle.
-Their smoothness of movement, increased accommodation, and many other
-advantages as compared with the old road omnibus, render it no longer
-necessary to call for special advocacy when there is a possibility of
-their introduction. They occupy
-<!--212.png--><a name="Page_200" id="Page_200"></a><span class="pagenum">[Pg 200]</span>
-a position so thoroughly appreciated
-by the public that any check on their reasonable use or extension
-would be considered as detrimental to the interests of the travelling
-community.</p>
-
-<p>As a rule, these tramways are laid down on streets or roads previously
-constructed for the ordinary road traffic, where all the preliminary
-work of earth filling, bridges, drainage, etc., has already been
-accomplished, and there only remains the selection and laying down of
-the rails or permanent way over which the tram-cars will have to run.
-The description and weight of permanent way to be adopted will depend
-largely upon the weight of the cars to be used and the system of
-motive-power decided upon for the haulage&mdash;whether horses, steam,
-cable, or electricity.</p>
-
-<p>As the portion of the streets or public roads along which the tramway
-has to be laid will, in all probability, have to be occupied and
-traversed by all kinds of vehicles besides the tram-cars, it is
-absolutely necessary that the permanent way for the tramway should be
-of such description as to require the least possible amount of
-adjustment of fastenings or opening out of the roadway for repairs.
-Where the entire width of the street, including the space between the
-tram-rails, is paved with stone setts, the opening out of even a short
-length for repairs is tedious and costly, and causes considerable
-obstruction to the street traffic. It is most important, therefore,
-that the rail and its fastenings should not only be strong enough for
-its own tram service and the carts and drays which will pass over and
-across the track in all directions, but it must possess the minimum
-necessity for disturbance.</p>
-
-<p><a href="#fig275">Figs. 275 to 279</a> are sketches of a few of the many types which have
-been brought into use in various places.</p>
-
-<p>Where the public roads are wide, and a space can be set apart at the
-side for the special use of the tramway, the arrangement shown in <a href="#fig275">Fig.
-275</a> will be simple and efficient. It is very similar to an ordinary
-railway permanent way with the ballast filled in flush with the top of
-the rails. The rails are shown as flange or flat-bottom rails, fished
-together at the joints, and properly secured to transverse sleepers of
-wood, iron, or steel. The space between and outside the rails is
-filled in with small-sized broken stone ballast or good clean gravel,
-and forms an even surface, over which animals or cattle may pass
-without risk of being thrown down.</p>
-
-<div class="figcenter">
- <a name="fig275"></a>
- <img src="images/i201.jpg"
- alt="Illustration: Figures 275 through 279"
- title="Figures 275 through 279"
- />
-</div>
-
-<p><a href="#fig275">Fig. 276</a> represents a system which was laid down extensively,
-<!--213.png--><!--214.png--><a name="Page_202" id="Page_202"></a><span class="pagenum">[Pg 202]</span>
-especially
-for horse tramways, but not proving efficient, has been superseded by
-other types of a stronger and more durable description. The rail was
-rolled with a continuous groove to provide clearance for the flanges
-of the car-wheels, and the sides of the rail were turned down so as to
-fit over the longitudinal timber sleeper, to which the rail was
-secured by staple-dogs, as shown. Cast-iron chairs, spiked on to
-wooden cross-sleepers, held the longitudinal sleepers in position. The
-wooden sleepers were favourable for smooth running, but the section of
-the rail, practically a light channel-iron laid on the flat, was most
-unsuitable for carrying weight or for making a proper joint.
-Experience proved this road to be very difficult to maintain in good
-order for easy traction. The staple-dogs worked loose after a little
-time, and the rail, having scarcely any vertical stiffness, rose and
-fell during the passage of every car-wheel, resulting in most uneven
-joints and a clattering roadway.</p>
-
-<p>With the view to obtain a stronger and more permanent support for the
-rail than the longitudinal timber sleeper last described, various
-forms of cast-iron chairs were devised. <a href="#fig275">Fig. 277</a> represents one of
-these patterns. The rail, which is of <strong>T</strong>-section with a
-continuous wheel-flange groove, is secured to the cast-iron chair by
-the cross-pin, as shown. Although this cross-pin may in time work a
-little loose, it cannot work out, being kept in position by the
-paving-setts on each side. The cast-iron chairs are placed at
-convenient distances, and being set in a bed of concrete, do not
-require cross-sleepers or tie-bars. This type makes a strong road, but
-the rail-joints cannot be made so even or efficient as with the more
-modern form of rail.</p>
-
-<p>Rail manufacturers are now able to roll a section of rail combining
-the vertical stiffness of the ordinary flange, or flat-bottom, rail
-with the running-head and continuous wheel-flange groove, considered
-the most suitable for heavy tramway traffic. The introduction of this
-section of rail has contributed greatly to the increased efficiency
-and durability of the permanent way for street traffic; and as the
-ends of the rails can be secured by ordinary fish-plates, there is the
-great acquisition of even joints and increased smoothness in the
-running of the tramcars. This rail can be rolled of various weights to
-suit the rolling loads. On some tram-lines a moderately heavy section
-has been adopted, and secured to transverse sleepers of rolled iron or
-steel laid on a bed of concrete. On others similar rolled metal
-sleepers have
-<!--215.png--><a name="Page_203" id="Page_203"></a><span class="pagenum">[Pg 203]</span>
-been used, but laid longitudinally. For some descriptions
-of traffic a much heavier section of rail has been used, having a base
-sufficiently wide to provide ample bearing on a bed of concrete
-without the intervention of either transverse or longitudinal
-sleepers.</p>
-
-<p><a href="#fig275">Fig. 278</a> is a sketch of the modern rail as laid down on a rolled steel
-transverse sleeper, the rail being held in position either by
-turned-up clips, wedges, bolts, or any of the devices in use for
-similar duty in the rolled-steel sleepers for ordinary railway
-permanent way.</p>
-
-<p><a href="#fig275">Fig. 279</a> shows a modern rail of a heavier section, with a wide flange
-resting direct on a continuous bed of concrete. The gauge is
-maintained by bar-iron tie-bars placed vertically so as to fit in
-between the courses of the paving-setts, the ends being forged and
-screwed to pass through holes in the vertical web of rail, and secured
-in position by nuts. Both in this, and in type <a href="#fig275">Fig. 278</a>, ordinary
-fish-plates are adopted at the rail-joints, as indicated by dotted
-lines.</p>
-
-<p>In the last two examples above described all the materials are of the
-most durable description, and the least liable to wear or decay, but
-it will be necessary to guard against making the fastenings and the
-bars too light for the duty they have to perform. There should be
-ample material in the head of the rail to allow of a fair wearing
-down, and the continuous flange groove should be sufficiently deep to
-meet this wearing away without causing the wheel-flanges to strike the
-bottom of the groove.</p>
-
-<div class="figcenter">
- <a name="fig280"></a>
- <img src="images/i204.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 280 through 291"
- title="Figures 280 through 291"
- />
-</div>
-
-<p class="p2"><strong>Fish-plates.</strong>&mdash;In the first examples of the newly invented
-wrought-iron fish-plates they were made to the depth to fit in between
-the upper and lower tables of the rail, as shown in <a href="#fig280">Fig. 280</a>, a small
-space or clearance being left between the inner sides and the vertical
-web of the rail. Ordinary nuts and bolts were used in most cases, but
-in some instances one of the fish-plates was tapped, as in <a href="#fig280">Fig. 281</a>,
-forming one long continuous nut, and in others both fish-plates were
-tapped, as in <a href="#fig280">Fig. 282</a>, and right and left handed bolts were used.
-Neither of the two arrangements of tapped fish-plates proved
-sufficiently successful as to lead to their general adoption. When the
-bolts became rusted in, or iron-bound, it was found to be almost
-impossible to remove them without permanently damaging the
-fish-plates. With the four right and left handed bolts the operation
-of tightening, or removing, the fish-plates was very tedious, as each
-<!--216.png--><!--217.png--><a name="Page_205" id="Page_205"></a><span class="pagenum">[Pg 205]</span>
-bolt had to be turned a very little at a time, one after the other.
-Independent bolts and nuts, either of iron or steel, are now
-universally used; plain holes, with sufficient allowance for work and
-expansion, being punched or drilled in the rails and fish-plates.</p>
-
-<p>For many years the depth of the fish-plates continued to be made the
-same as the space between the upper and lower members of the rail, as
-shown in <a href="#fig280">Fig. 280</a>; but with the heavier loads and higher speeds of our
-modern railway working it has been found necessary to strengthen the
-joints by providing deeper or stiffer fish-plates, as shown in <a href="#fig280">Figs.
-283, 284, and 285</a>. For bull-head rails the fish-plates have been
-brought down underneath the lower table, and in some cases extended
-down sufficiently far to admit of a second set of fish-bolts under the
-rail. For flange rails some fish-plates are used simply of the form of
-angle irons, and others have the angle portion carried out beyond the
-end of the flange, or foot of rail, and then turned down vertically to
-a depth of an inch or more below the rail. The latter makes a very
-strong fish-plate.</p>
-
-<p>Fish-plates, like rails, are now almost universally made of steel.</p>
-
-<p>The efficiency and durability of a fish-plate depends materially upon
-its angle of contact with the under side of the head of the rail, and
-the extent of its contact surface. It would be an error to suppose
-there is little or no wearing away in fish-plates, as in reality there
-is very considerable wear, and especially in rails of lighter section.
-If the under side of the head of rail has a curved outline, as in the
-rail in <a href="#fig280">Fig. 287</a>, there will be some difficulty in ensuring a perfect
-fit in the fish-plates; the curve of the one may not quite correspond
-to the curve of the other, and the contact surface will be very small.
-It is better to make these contact surfaces in straight lines, and to
-a wide angle rather than to an acute angle. In <a href="#fig280">Fig. 288</a> the under side
-of head and corresponding top of fish-plates are set at an acute
-angle, and fish-plates to this pattern will soon wear up to the
-vertical web of rail, and cause a loose noisy joint.</p>
-
-<p>In <a href="#fig280">Fig. 284</a>, showing a different type of rail, the contact surfaces
-are set at a very much wider angle, and will allow much more wear
-before the fish-plates can work close up to the web of the rail.</p>
-
-<p>When once the fish-plates are close up to the web, the best
-<!--218.png--><a name="Page_206" id="Page_206"></a><span class="pagenum">[Pg 206]</span>
-and
-tightest bolts cannot prevent the vertical play in the ends of the
-rails.</p>
-
-<p>A hammering sound will announce each successive drop of the wheels
-from one rail to the other, more distinctly, perhaps, at slow speeds
-than when travelling quickly, but existing equally under both
-conditions. The unpleasant jarring sensation is annoying to the
-passengers, and has a straining, loosening effect on all the bolts and
-fastenings. Unless the fish-plates have a thorough continuous bearing
-against the upper and lower shoulders of both the rails, it will be
-impossible to obtain a smooth even joint. A road may have good rails,
-good chairs, and good sleepers, but if the fish-plates are worn and
-loose the entire permanent way may be pronounced faulty, and all on
-account of a minor defect which can be easily remedied. With strong,
-properly fitting fish-plates, the position of the joints should be
-imperceptible when passing over them in a train.</p>
-
-<p>The writer has had many miles of line where the fish-plates have worn
-hard up to the rail web. In cases where the rails were good, with the
-prospect of a long life, new fish-plates of suitable section have been
-provided. In others, thin wrought-iron plate liners, 1/16 or 1/12 of
-an inch thick, have been inserted, as in <a href="#fig280">Fig. 291</a>, so as to bring the
-plates well out from the web, and allow the fish-bolts and fish-plates
-to exercise the free gripping action which is absolutely necessary to
-prevent the vertical rising and falling of the rail-ends during the
-passage of a rolling load. Fish-plate liners of the above description
-have given excellent results, and have restored the efficiency of the
-fish-plates for several years.</p>
-
-<p class="p2"><strong>Chairs.</strong>&mdash;All rails which partake of the double head section, or have
-a base not wider than the head, require supports or carriers to attach
-them to the sleepers, and to secure them in their proper upright
-position. In the days of the original <em>edge rails</em>, at the
-commencement of the railway era, these supports were very
-appropriately termed <em>chairs</em>, and this name has now been adopted in
-all parts of the world. Cast-iron is the most suitable material for
-railways chairs, being much cheaper in cost and less liable to loss or
-deterioration from rust than wrought-iron. Cast-iron chairs can be
-formed to suit any section of rail, and from the nature of the
-material they cannot be bent or twisted out of shape so as to
-interfere with the gauge or cant. They may break during an accident or
-derailment, but the
-<!--219.png--><a name="Page_207" id="Page_207"></a><span class="pagenum">[Pg 207]</span>
-fracture can be detected at once, and the broken
-chair quickly replaced.</p>
-
-<p>The chair performs the very important duty of distributing the weight
-of the rolling load on the upper surface of the sleeper. If the under
-side or base of the chair is small, and the rolling load large, the
-chair will very rapidly wear or imbed itself into the wood of the
-sleeper, shortening the life of the latter in a very palpable manner.
-The short narrow chair naturally gives less stability than the larger
-and broader chair. The chair shown in <a href="#fig292">Fig. 292</a>, which was much used
-for 75 lb. rails some twenty years ago, has much less base area and
-stability than the chair shown in <a href="#fig292">Fig. 293</a>, adopted for rails of a
-similar weight in the present day. The former had a bearing surface on
-the sleeper of only 53 square inches, as compared with 89 square
-inches in the latter. The base area of the chair must be in proportion
-to the weight it has to carry and distribute, and it would be false
-economy to stint the surface area of one of the details which
-influences so materially the stability and durability of the permanent
-way.</p>
-
-<p>As will be seen in <a href="#fig292">Figs. 294, 295, and 296</a>, the chairs at present used
-for 80, 85, and 90 lb. rails have a much larger bearing surface than
-the chair shown in <a href="#fig292">Fig. 292</a>.</p>
-
-<p>With the wider chair, a much longer and better seat can be given to
-the under table of rail, and a greater length of jaw for holding the
-wooden key. The longer the rail-seat the steadier the rail and the
-smoother the running.</p>
-
-<p>The keys are generally made of hard wood, sometimes compressed by a
-special process, cut slightly taper, or wedge, shape, and driven in
-between the jaw of the chair and the vertical web of the rail. On some
-railways the key is placed outside the rail, as in <a href="#fig292">Fig. 297</a>, and on
-others inside the rail, as in <a href="#fig292">Fig. 298</a>. The latter method possesses
-many advantages over the former. The outer jaw of the chair can be
-brought well up to the under side of head of rail, giving the rail
-more lateral support and better means of preserving the correct cant;
-and, as in this chair the outer jaw permanently fixes the gauge, the
-working out of one or more of the keys does not leave the rail exposed
-to be forced outwards and widen the gauge, as in the case with dropped
-keys in outside keying. Another and very important advantage of inside
-keying is that platelayers, when inspecting the road by walking
-between the rails, can readily examine the keys on both sides.</p>
-
-<div class="figcenter">
-<!--220.png--><a name="Page_208" id="Page_208"></a><span class="pagenum">[Pg 208]</span>
- <a name="fig292"></a>
- <img src="images/i208.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 292 through 306"
- title="Figures 292 through 306"
- />
-</div>
-
-<p><!--221.png--><a name="Page_209" id="Page_209"></a><span class="pagenum">[Pg 209]</span>
-Chairs have been made, as in <a href="#fig292">Fig. 299</a>, with a recess in the rail-seat,
-to hold a piece of prepared wood, or other suitable semi-elastic
-material, the object being to provide a rest, or cushion, softer and
-more yielding than the cast-iron. The idea looks well in theory, but
-in practice the pounding on the rail compresses or crushes the wood
-lower and lower into the recess, slackened keys have to be tightened,
-and when the wood has been worn or crushed away down to the level of
-the stop ribs, <strong>A</strong>, <strong>A</strong>, the under side of rail has no longer any
-seat, or rest, beyond the two narrow ribs of cast-iron. These afford
-such a very limited support that the rail becomes notched, and
-produces a very rough clattering road. It is a very simple matter to
-take out an old key and put in a new one, but to replace a wooden
-cushion in a chair recess involves the entire removal of either the
-rail or the chair. Chairs with wooden cushions have not been adopted
-to any great extent, the tendency of modern practice being to reduce
-as far as possible the number of parts of the permanent way, and to
-provide those parts with ample bearing or contact surfaces.</p>
-
-<p>Although the general practice has been to cast the chairs in one
-piece, chairs have been made in two pieces, as in <a href="#fig292">Fig. 300</a>, fastened
-together and to the rail by a bolt passing through the latter, the
-castings being secured to the sleeper with spikes. At first sight this
-pattern of chair appeared to possess some features in its favour. The
-castings were simple, keys were dispensed with altogether, and the
-under side of rail was not in contact with the cast-iron. A short
-experience, however, proved that the drawbacks far outweighed the
-apparent advantages. Holes for the through-bolts had to be punched at
-fixed distances in the rails, and although this could be readily done
-at the works, for the general use on the line it was necessary to
-resort to the tedious process of drilling by hand for a large number
-of holes on curves, and for rails cut to form <em>closers</em>.</p>
-
-<p class="p2"><strong>Sleepers.</strong>&mdash;Wood possesses so many suitable qualities that we can
-readily understand why it was early selected as the proper material
-for sleepers. It can be cut to any size and shape, holes can be bored,
-spikes can be driven, and bolts can be screwed into it without any
-difficulty and without causing injury to the timber, while the
-semi-elastic nature of wood absorbs the vibration of the rails and
-fastenings, and provides a sound-deadening seat so conducive to smooth
-running. Its only drawback is that
-<!--222.png--><a name="Page_210" id="Page_210"></a><span class="pagenum">[Pg 210]</span>
-it is perishable from wear and
-decay. Were it not for this defect, railway sleepers of wood might be
-considered as simply perfect.</p>
-
-<p>With a view to greater permanency and durability, stone sleepers were
-tried. These consisted of square blocks of good hard stone, measuring
-about 2 feet wide each way and 12 inches thick. Holes were cut in the
-stone, and plugs of hard wood inserted. The cast-iron chairs were then
-placed on the top of the blocks, and the iron spikes driven through
-the chair-holes into the wooden plugs. The elements of permanency were
-there certainly, but a rougher road it would be impossible to
-conceive. The stone was solid and unyielding, there was a total
-absence of softness and elasticity, and the harsh noisy effect
-produced when running over the stone-block road very soon became
-intolerable. Stone-block sleepers were found to be a failure, and were
-all removed. On some of our old lines, numbers of them, with the chair
-marks plainly visible, may be still seen in loading banks, buildings,
-sea walls, and other works for which they were never originally
-intended, but for which their size and weight render them very
-appropriate.</p>
-
-<p>Wooden sleepers are used in two forms, transverse and longitudinal. In
-the former, as in <a href="#fig292">Fig. 301</a>, the sleepers not only carry the rails, but
-also preserve the gauge; in the latter as in <a href="#fig292">Fig. 302</a>, the
-longitudinal sleepers only support the rails, additional timbers and
-strong fastenings being necessary to maintain the gauge.</p>
-
-<p>Longitudinal sleepers have been used to a large extent for bridge
-rails, it being supposed that with the broad continuous sleeper a
-lighter and shallower rail could be adopted, which would be equally
-efficient as a heavier rail on cross-sleepers. Excellent running roads
-have been made with longitudinal sleepers, notwithstanding the
-difficulty of making a good bridge-rail joint; but it is well to bear
-in mind that almost all the lines which originally adopted this form
-of permanent way have since reverted to the ordinary cross-sleeper
-road. The longitudinal sleeper road is an expensive road to lay down
-and maintain. The main pieces are of large scantling, must be of good
-quality of timber, and are consequently costly. The cross-pieces, or
-transomes, must be carefully fitted and secured with heavy ironwork.
-Where there is much traffic, the removal and renewal of one of the
-long timbers is much more difficult than the renewal
-<!--223.png--><a name="Page_211" id="Page_211"></a><span class="pagenum">[Pg 211]</span>
-of several ordinary
-cross-sleepers. Again, decay may take place on only one portion of a
-main timber, but there is no alternative but to remove the entire
-piece.</p>
-
-<p>For gauges varying from 4 feet 8½ inches to 5 feet 3 inches,
-cross-sleepers are cut to the length of 8 feet 11 inches, and are
-generally rectangular in section, as in <a href="#fig292">Fig. 303</a>, measuring 10 inches
-in width by 5 inches in thickness. On some of the lighter railways
-with small traffic, sleepers are often used only 9 inches wide by 4½
-inches thick, while occasionally on some lines, and in places where
-there is exceptionally heavy and constant traffic, sleepers 12 inches
-wide by 6 inches thick are adopted.</p>
-
-<p>Half-round sleepers, as in <a href="#fig292">Fig. 304</a>, are used on many lines because
-they are cheaper. In some cases the flat side of the sleeper is placed
-downwards, and the rail or chair is fastened into an adzed seat cut in
-the round side; and in the others the round side is placed downwards,
-and the flat side of the sleeper carries the rail or chair. Triangular
-sleepers, as in <a href="#fig292">Fig. 305</a>, have also been used, made by cutting the
-blocks diagonally, so as to obtain the greatest possible width. They
-were laid with the flat side upwards, and the apex downwards. They
-were difficult to keep packed, and have not been adopted to any great
-extent.</p>
-
-<p>With the exception of a limited number of larch and fir sleepers grown
-in the country, most of the sleepers for our home railways are
-imported from the Baltic. They are brought over in logs, or blocks,
-each 8 feet 11 inches long, some square and others circular in
-section, and when sawn down the middle, each block forms two sleepers.</p>
-
-<p>The preservation of timber from decay is a subject that very early
-occupied the attention of engineers and all those interested in
-railways. A railway sleeper is particularly exposed to deterioration
-the lower portion being surrounded with moist ballast, whilst the top
-portion is more or less uncovered&mdash;two different conditions in the
-same piece of timber. Several processes have been tried, such as
-Kyanizing, Burnetizing, Boucherizing, etc., but the system which has
-given the best results, and is now almost universally adopted, is that
-known as creosoting. This method consists of forcing liquid creosote,
-under considerable pressure, into sleepers or railway timbers which
-have been prepared or dried by ordinary natural seasoning or by
-special artificial means. Creosote is a dark, oily liquid,
-<!--224.png--><a name="Page_212" id="Page_212"></a><span class="pagenum">[Pg 212]</span>
-distilled
-from coal tar, varying in its composition according to the quality of
-the coal from which it is obtained, and ranging in its specific
-gravity from 11·08 to 10·28.</p>
-
-<p>Creosote oils of light specific gravity were at one time in favour,
-but experience proved that, to some extent, the light oils were
-volatile and also soluble in water, and that heavy rains washed out
-the constituents which were essential for the preservation of the
-timber. On the other hand, by heating the heavy oils and using high
-pressure the napthaline which is dissolved only by the heat, is forced
-into the wood, fills the pores, and solidifies.</p>
-
-<p>Creosote is obtainable in large quantities, at prices varying from
-twopence to fourpence per gallon, according to the demand and cost of
-production. Newly delivered sleepers or railway timber contain so much
-sap or water that it is impossible to force a sufficient quantity of
-creosote into them until they are properly seasoned or dried.</p>
-
-<p>The seasoning is generally arranged by sawing each block into two
-sleepers, and then stacking the sleepers on edge in tiers, leaving a
-space of four or five inches between each of them for a proper
-circulation of air. The sleepers should then be left for nine to
-twelve months to season, although more may be necessary in some cases
-if the blocks were particularly wet at the time they were sawn.</p>
-
-<p>When ready for the process the sleepers are placed in the creosoting
-cylinder, which is generally about 60 feet long by 6 feet in diameter
-with semi-spherical ends. One of the ends is fitted with strong hinges
-and fastenings, and forms the doorway. The sleepers are packed
-carefully inside, and the doorway made tight. The machinery is then
-set to work to exhaust the air from the cylinder and allow the
-creosote to flow in amongst the sleepers. When the cylinder is full
-the force-pumps are started to force in more creosote up to the
-pressure prearranged and regulated by the safety-valve, in some cases
-100, 110, or 120 lbs. per square inch. The creosote should be heated
-to 112° or 120° Fah., to dissolve the napthaline and reduce all the
-component parts to a thoroughly fluid condition.</p>
-
-<p>The success of creosoting depends almost entirely upon the effectual
-seasoning of the timber. Only a very small quantity of creosote can be
-forced into wet or unseasoned sleepers, even with the best machinery
-and exceptionally high pressures, while
-<!--225.png--><a name="Page_213" id="Page_213"></a><span class="pagenum">[Pg 213]</span>
-a thoroughly dry sleeper will
-readily absorb from 2⅓ to 3 gallons. More could be forced into the dry
-sleeper if necessary, but a little consideration will show there would
-be no advantage in doing so. In railway sleepers there are two
-elements of destruction at work&mdash;one the decay of the timber, and the
-other abrasion or wearing away of the wood itself from the constant
-pounding of the passing loads.</p>
-
-<p>More particularly does this wearing-away take place with the flange,
-or bridge, rails, their distributed bearing surface on the sleeper
-being less than the cast-iron chairs.</p>
-
-<p>A thoroughly well-creosoted 5-inch sleeper laid originally with a
-thickness of 4-¾ inches in the centre of rail-seat, as in <a href="#fig292">Fig. 306</a>,
-will wear down 1½ inches, the timber remaining quite sound.</p>
-
-<p>The writer has had to take out thousands of sleepers where the seats
-of the flange, or bridge, rails had been pounded or worn down so deep
-into the wood as to leave too small a thickness of timber to carry the
-rail with safety. These sleepers had to be taken out of the road, not
-on account of decay, but because they were actually worn down too thin
-to be of service. They had done their work well for a long series of
-years, and were perfectly sound when taken out. No increased quantity
-of creosote would have made them last longer, and any increased
-quantity of creosote would have been waste.</p>
-
-<p>Two and three quarter gallons of creosote is a very good and suitable
-quantity for a 10 inch by 5 inch rectangular sleeper, but not more
-than half this quantity can be forced in if the sleeper is wet or
-unseasoned.</p>
-
-<p>Sleeper-blocks are generally cut from the upper part of the tree, and
-do not therefore consist of the best portion of the timber, yet
-sleepers made from the soft, coarse-grained Baltic wood, properly
-creosoted, will last from twelve to eighteen years in the line in this
-country, while uncreosoted they would perish from decay in six or
-seven. The benefit is great when, by adding from eightpence to a
-shilling for the cost of creosoting, the life of the sleeper may be
-doubled or trebled. Of course, there are countries, like the far west
-of America, where the lines pass through vast forests, and where
-sleepers may be had for the mere cost of cutting. Creosoting in those
-places would be out of the question, and would cost four or five times
-the value of the plain sleeper. It is found, also, that in tropical
-countries and
-<!--226.png--><a name="Page_214" id="Page_214"></a><span class="pagenum">[Pg 214]</span>
-in dry climates at high altitudes creosote loses its
-efficiency, and in those districts the best creosoted soft-wood
-sleeper perishes from a species of dry rot in three or four years.
-Where wood sleepers have to be used in tropical climates it is better
-to obtain them from the timber of the district, although in many cases
-suitable trees are difficult to procure and the cost of land transport
-is very heavy.</p>
-
-<p>The soft cushion-like effect of a sound, properly packed wooden
-sleeper contributes so largely to form an easy, smooth-running road,
-that so long as they can be obtained at a moderate cost, and are
-fairly durable, wooden sleepers will always be preferred to those of
-any other material. The great question will be the supply. Creosoting
-and other wood-preserving processes have done much to prolong the life
-of sleepers, but the rapidly increasing extent of mileage throughout
-the world, together with the enormous number of sleepers required
-annually for maintenance or renewals, must before very long severely
-tax the powers of supply.</p>
-
-<p>In the great timber-producing territories the axe is often heard, but
-the planter is rarely seen. Vast forests are cleared away, and their
-sites transformed into busy towns or cultivated lands; and unless some
-great change takes place, and planting be carried out on a large
-scale, some other material will have to be adopted for this important
-item of our permanent way.</p>
-
-<p>Appearances would indicate that at no very distant date iron or steel
-will take a conspicuous part in the formation of future railway
-sleepers.</p>
-
-<p>More than thirty years ago several descriptions of cast-iron sleepers
-were introduced into notice and tried on some of our leading home
-railways. Cast-iron was at that time considered more suitable for the
-purpose than wrought iron, as it was very much less costly in price,
-and could be readily worked into any desired form or size, with the
-advantage that the castings would all be duplicates of one another.</p>
-
-<div class="figcenter">
- <a name="fig307"></a>
- <img src="images/i215.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 307 through 313"
- title="Figures 307 through 313"
- />
-</div>
-
-<p><a href="#fig307">Figs. 307 to 313</a> show some of the types that were designed and laid
-down in the road. In <a href="#fig307">Fig. 307</a> the sleeper and chairs were all cast
-together in one piece; the rail was held in its place by wooden keys,
-and the gauge of the line was maintained by transverse wrought-iron
-tie-bars. The sketch represents one of the sleepers used at the
-rail-joints, and has three chairs, the larger one in the centre being
-for the support of the ends of
-<!--227.png--><!--228.png--><a name="Page_216" id="Page_216"></a><span class="pagenum">[Pg 216]</span>
-the rails. This arrangement was the
-same as was then in use on the ordinary wood-sleeper road, where an
-extra large chair was placed at the rail-joints, and was the most
-approved method for many years before fish-plates were introduced. The
-intermediate sleepers were shorter, and had only two chairs.</p>
-
-<p><a href="#fig307">Fig. 30</a>8 represents a long, flat, cast-iron sleeper made in two
-halves, bolted together just below the under side of rail at each of
-the three chair-seats. The rail was gripped and held in position
-without the use of wooden keys. This being a joint sleeper, three
-chairs were used, as in <a href="#fig307">Fig. 307</a>. Only two chairs were used on the
-intermediate sleepers.</p>
-
-<p><a href="#fig307">Figs. 309 and 310</a> are somewhat similar, but the circular one is higher
-and more cup-shaped than the other of oval form. The oval pattern has
-two small recesses for holding two small hard-wood cushions. The
-circular holes shown in the sides of the sleepers were intended to
-facilitate the packing, or tamping, of the light sandy ballast.</p>
-
-<p><a href="#fig307">Fig. 311</a> represents a rectangular cast-iron sleeper, as used for the
-flange rail. The rail rests on cast-iron cross-ribs, bevelled to give
-the proper cant, and is held in position by the tie-bar bolt and
-clip-piece, as shown. The small projecting lug, formed on the under
-side of sleeper, fits into a corresponding notch in the tie-bar, and
-keeps the sleepers to gauge. The tie-bar passes through the loop end
-of the same bolt which secures the rail, and is held up tight against
-the under side of sleeper.</p>
-
-<p><a href="#fig307">Figs. 312 and 313</a>, both the same in principle, possessed features
-which appeared to give great promise. They were simple in
-construction; the rail was kept well down, and did not come in contact
-with the cast-iron at any point. The long wooden wedges, which fitted
-into the rough or serrated sides of the casting, acted as a cushion to
-the rail, and were intended to sink deeper into the recess as the
-super-imposed weight increased, or the wood became thinner from
-shrinkage. In practice, however, it was found that these sleepers were
-not the success that was anticipated.</p>
-
-<p>It was soon observed that sand and fine particles of gravel from the
-ballast worked their way into the lower part of the recess, and became
-so compact as to prevent the wooden wedges working further down to
-increase their grip on the rail. Even when the recess was kept free
-and clear of sand, the enormous pressure exerted by the wooden wedges
-broke the iron at <strong>A</strong>,
-<!--229.png--><a name="Page_217" id="Page_217"></a><span class="pagenum">[Pg 217]</span>
-although an extra thickness was given to that
-part of the section. The cast-iron was exposed to the greatest strain
-at the point where it was the least capable of offering resistance.</p>
-
-<p>Much ingenuity was displayed in many of the patterns brought forward,
-but in dealing with a hard unyielding material like cast-iron, it is
-difficult, if not impossible, to impart any soft, elastic effect; and
-the different systems of cast-iron sleepers failed to become popular
-on our home railways, on account of the noise and vibration when
-trains passed over them. Another objection was the great multiplicity
-of parts required in many of the types, and the constant and severe
-strain produced on the fastenings on the passing of every wheel. The
-bolts might be made tight at first, but the incessant shaking would
-work them loose, the threads became stripped, and the rails ceased to
-be held in a proper and secure position.</p>
-
-<p>The cast-iron sleeper road was considered unsuitable for the heavy and
-fast traffic of our home lines, and was ultimately all taken up and
-replaced with wooden transverse sleepers. At the same time, there is
-no doubt that cast-iron sleepers have been of great value in India and
-tropical climates, where timber sleepers were not only scarce, but
-perish very rapidly. Very large numbers of them have been laid down
-abroad of patterns very similar to those shown in <a href="#fig307">Figs. 309, 310, and
-311</a>, and have done good service for many years. They are not affected
-by rain or heat, but, unfortunately, being castings, are liable to
-considerable annual loss from breakage.</p>
-
-<p>Improvements in plate-rolling machinery, and in appliances for bending
-and stamping wrought-iron, have materially assisted in developing the
-introduction of wrought-iron and steel sleepers. Cast-iron and
-wrought-iron are, in the abstract, hard and non-elastic as compared
-with wood; but whereas cast-iron can only be made into fixed,
-unyielding shapes, wrought-iron and steel can be worked into forms
-that possess a certain spring-like effect, which not only enables them
-almost entirely to resist fracture, but also imparts a measure of
-elasticity to the permanent way.</p>
-
-<p>The simplest form of wrought-iron sleeper would be a plain, flat
-plate, to which the chair, or rail-bracket, would be attached; but as
-this form would have bearing surface only, without any lateral hold on
-the ballast to keep the rails to line, it could not be adopted.</p>
-
-<p><!--230.png--><a name="Page_218" id="Page_218"></a><span class="pagenum">[Pg 218]</span>
-During the last few years very many types of wrought-iron and steel
-sleepers have been introduced, and nearly all of them of the
-transverse-sleeper pattern, formed out of rolled plates; the sides,
-and in some cases the ends also, are bent, or turned down to obtain a
-hold in the ballast. Where bull-head or double-head rails are used,
-cast-iron chairs, or wrought-iron bracket chairs, are bolted, or
-otherwise secured to the upper surface of the sleeper, a layer of
-felt, tarred paper, or other soft material being placed between the
-two metal surfaces. Where flange rails are used, they are fastened to
-the sleepers either by bolts, clamps, or clips raised up out of the
-iron sleeper, and bent over to hold tightening keys. Rolled transverse
-sleepers can readily be bent, or set in the centre to give the proper
-cant at the rail-seat; and in some types the sleepers are pressed in
-the machines, so as to be narrower towards the centre, and with a
-deeper turnover, to obtain increased stiffness.</p>
-
-<p>In <a href="#fig314">Figs. 314 to 319</a> are shown some of the patterns which have been
-brought out, laid down in actual practice, and in use at the present
-time.</p>
-
-<p>From the fact that wrought-iron and steel sleepers have been laid down
-in so many places where cast-iron sleepers were discarded or refused a
-trial, it is evident that the former are considered to have qualities
-which the latter did not possess. Rolled iron or steel sleepers are
-coming more and more into use, especially on foreign or colonial
-railways. So long, however, as good, well-creosoted timber sleepers
-can be obtained for our home railways at prices from 3<i class="money"><abbr title="shillings">s.</abbr></i> 8<i class="money"><abbr title="pence">d.</abbr></i> to
-4<i class="money"><abbr title="shillings">s.</abbr></i> 8<i class="money"><abbr title="pence">d.</abbr></i> each, and last from fourteen to twenty years, there is
-little probability that they will be supplanted by iron sleepers at
-double the cost. But abroad the circumstances of cost and durability
-are different, and there the rolled iron or steel sleepers, which will
-outlive two or three sets of wooden ones, must claim advantages which
-cannot be overlooked. The difficulty will be in the fastenings, the
-mode of attaching the rails to the sleepers. The constant hammering of
-metal upon metal, resulting from the vibrations of every passing load,
-will quickly wear or loosen bolts, rivets, or wedges, and the
-fastenings which will prove the most efficient will be those that are
-the simplest and most readily adjusted.</p>
-
-<p class="p2"><strong>Fastenings.</strong>&mdash;Figs. 320 to 335 illustrate some types of the principal
-fastenings used in connection with the chair road, and with
-flat-bottomed or flange rails.</p>
-
-<div class="figcenter">
-
-<!--231.png--><a name="Page_219" id="Page_219"></a><span class="pagenum">[Pg 219]</span>
- <a name="fig314"></a>
- <img src="images/i219.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 314 through 319"
- title="Figures 314 through 319"
- />
-</div>
-
-<p><!--232.png--><a name="Page_220" id="Page_220"></a><span class="pagenum">[Pg 220]</span>
-The fish-bolts, <a href="#fig320">Figs. 320 and 321</a>, are of a form which is in very
-general use both for steel bull-head rails and steel flange rails. By
-making the neck square or pear-shaped, to fit into corresponding hole
-in the fish-plate, the bolt is prevented from turning round when the
-wrench or spanner is applied to tighten the nut. A channel or groove
-is sometimes rolled on the outside of fish-plate to grip bolts made
-with square heads. Some engineers adopt two nuts, others prefer one
-nut of extra depth. Washers are used in some cases, but are not
-universal. With a deep rail it is preferable to place the nuts inside,
-so that the platelayer inspecting his length can see both rows of nuts
-as he walks along between the rails. With shallow rails the nuts must
-be placed outside and the cup-heads inside, to give ample clearance to
-the wheel-flanges.</p>
-
-<p>Fish-bolts are subject to very severe work. Heavy rolling loads
-passing over the rail-joints&mdash;frequently at very high speeds&mdash;bring
-into play all the gripping power of the fish-bolts to maintain a firm
-support of the fish-plates to ends of rails, and the constant action
-of pressure and release produces a loosening or unscrewing motion in
-the bolts which is very difficult to counteract. Loose fish-bolts
-cause clattering joints and uneven road, and unless promptly remedied,
-the screw threads are soon destroyed and bolts rendered useless. Many
-devices have been invented to prevent or check this loosening of the
-bolts; one of the methods, and a very simple one, consists of a plain
-steel bolt with a steel lock-nut, made as shown in <a href="#fig320">Fig. 322</a>. As will
-be seen from the section, one-half of the nut is tapped of the same
-size as the bolt, and the remainder with deep-locking threads. The
-first half of the nut is readily screwed on to the bolt, but
-considerable force must be exerted to screw on the portion having the
-deep-locking threads; practically the second half of the nut has to
-cut a new or deeper thread for itself when screwing round the bolt.</p>
-
-<div class="figcenter">
- <a name="fig320"></a>
- <img src="images/i221.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 320 through 335"
- title="Figures 320 through 335"
- />
-</div>
-
-<p>The slits or grooves at the angles of the nuts form four distinct
-cutting edges for shaping the deep threads. As the upper part of the
-lock-nut is divided by the grooves into four separate or detached
-segments, these segments will be forced slightly open or outwards
-during the action of cutting the deep thread on the bolt, and from
-their natural tendency to return to their original position they must
-exercise a strong gripping power on the bolt. This combined operation
-of cutting the deep
-<!--233.png--><!--234.png--><a name="Page_222" id="Page_222"></a><span class="pagenum">[Pg 222]</span>
-threads and of forcing open the upper or detached
-segments, give an enormous holding and retaining power to the
-lock-nut, and enables it to withstand the train vibrations for a very
-long time without any perceptible slackening. In case of line repairs
-the nut can be readily unscrewed, and taken off the bolt.</p>
-
-<p>Round iron spikes, as in <a href="#fig320">Figs. 323 and 324</a>, and round wooden trenails,
-as in <a href="#fig320">Fig. 325</a>, are both used for fastening cast-iron chairs to the
-sleepers. The spikes are made with a slightly taper neck, of size
-rather less than the hole in the chair, to avoid risk of breaking the
-casting when driving the spike down. Trenails are made out of
-well-seasoned hard wood, and are compressed by machinery. When driven
-into the sleeper, they expand by exposure to the atmosphere, and hold
-the chair very securely in position; but being only wood and of very
-small scantling, they are subject to early decay. The head, which is
-the only part in sight, may be perfectly sound, while the part between
-the chair-seat and top of sleeper may be quite rotten and useless. It
-would be very risky to depend upon trenails alone; one spike at least
-should be used to every chair. In some cases an extra large trenail is
-used with an augur-hole down the centre, through which either an iron
-spike is driven or a bolt is passed and screwed into a crab-nut on the
-under side of the sleeper. This arrangement will work well for a time,
-but there will be a great deal of play in the spike or bolt when the
-trenail becomes much decayed.</p>
-
-<p>The spikes represented in <a href="#fig320">Figs. 326, 327, and 328</a>, are much used with
-flange rails. They are square in section, and finished with either
-blunt or sharp points, as shown. The top of spike is made with a
-doghead and side-lugs to facilitate the easing or withdrawal when
-necessary for renewals of sleepers, or alterations in line. By
-inserting the curved double claw end of a platelayers’ crowbar, the
-spike can be raised without injuring the sleeper; but if it is
-required to be driven into the same sleeper again, a new hole must be
-bored, as the old hole will be too slack to be of any service.
-Augur-holes must be bored in the sleepers for the above spikes. For
-new roads, these holes can be bored by machinery when cutting the
-grooves for rail-seats; but when carrying out alterations or repairs,
-a large number of spike-holes must be bored by hand-augurs, an
-operation both slow and laborious. With the hand-boring there is the
-danger that the hole may not be made deep enough, owing to
-<!--235.png--><a name="Page_223" id="Page_223"></a><span class="pagenum">[Pg 223]</span>
-the workman’s
-endeavour to avoid damaging the point of his augur by forcing it
-entirely through the sleeper, and bringing it in contact with a stone.
-Augur-holes bored wide to gauge will remain out of gauge, and although
-the spike may be driven down firm in its position, a space will be
-left for play between the rail-flange and spike.</p>
-
-<p><a href="#fig320">Fig. 329</a> is a sketch of a dog-spike for flange rails which the writer
-has used for many years both abroad and at home, and which can be
-driven without any boring at all. The back of this spike is made
-perfectly straight, half of the front side is made parallel to the
-back, and the remainder is tapered down to a chisel point not
-exceeding 1/16 of an inch thick, the entering edge on the face being
-narrowed down to 3/8 of an inch in width. Three jags or spurs are cut
-on each side of the tapered portion, or twelve in all, and add greatly
-to the holding power. Not only can this spike be driven without any
-boring, but it possesses the additional advantage that in driving it
-down its taper or wedge-like shape causes it to drift hard up to the
-edge of the flange of rail, an element of great value in securing the
-exact gauge of line. With these spikes permanent-way laying can be
-carried on very rapidly, and they are especially valuable when making
-alterations, as augurs for spike-boring can be dispensed with
-altogether.</p>
-
-<p>Wood screws with square heads similar to <a href="#fig320">Fig. 330</a> are sometimes used
-for fastening flange rails to wooden sleepers. They are passed through
-holes punched or drilled in the flanges of the rails, and are intended
-to preserve the gauge as well as secure the rails to the sleepers.
-Experience has shown that these wood screws possess very limited
-holding power. The screwed portion of the bolt cuts but a very
-imperfect and weak holding thread in the soft wood of an ordinary
-sleeper, moisture insinuates itself into the bolt-hole, rusting the
-bolts and decaying the surrounding timber, and in a very short time
-the bolts become loose and incapable of holding the rail down firmly.
-As permanent-way fastenings wood screws are very inferior to crab
-bolts.</p>
-
-<p>Crab bolts, as in <a href="#fig320">Fig. 331</a>, may be made either with square or
-hexagonal heads, and with three spur-nuts or four spur-nuts, as in
-<strong>A</strong> or <strong>B</strong>. The length of the bolts will depend upon the thickness of
-the sleeper or timber-work through which they have to be inserted. The
-bolt is pushed down through the hole bored in the sleeper, and the
-crab-nut put on from underneath.
-<!--236.png--><a name="Page_224" id="Page_224"></a><span class="pagenum">[Pg 224]</span>
-With a few turns of the bolt, the
-crab-nut is brought close up to the under side of the sleeper, the
-spur-points become embedded in the wood, and hold the nut firmly in
-position during subsequent tightening of the bolt. Crab bolts are
-extensively used with flange or flat-bottomed rails, and also in
-switch chairs and in crossings. A large number of flange rails are
-used with one hole through the flange at each end of rail, and a crab
-bolt passed through the hole and through the sleeper next to the
-joint, as shown in <a href="#fig320">Fig. 332</a>. This system checks the creeping of the
-rails by effectually securing or anchoring each rail to two of the
-sleepers. As there is always a tendency for these rails to crack
-through to the outside at the flange-holes, it is very desirable to
-have as few holes as possible. The two above described will be found
-sufficient for all practical purposes. To avoid punching or drilling
-more holes in the flanges of the rails, additional or intermediate
-crab bolts can be used by means of the fang clips shown on <a href="#fig320">Fig. 333</a>.
-The crab bolt is passed through the fang clips and through the sleeper
-close up to the flange of rail, and by screwing it round in the
-crab-nut under the sleeper the fang-clip is pressed down until the two
-spurs are driven into the timber, and the rail held securely in its
-place and to gauge. Intermediate crab-nuts and fang-clips should
-always be used in pairs, one on each side of the rail. Possessing more
-holding-down power than ordinary spikes, they are particularly
-valuable on sharp curves.</p>
-
-<p>In some cases flange rails are laid in small cast-iron saddles, or
-chairs, as shown in <a href="#fig320">Fig. 334</a>, one end of the rail-seat having a recess
-to prevent the rail tilting upwards and outwards. An ordinary spike
-may be used for the inside end of chair, and a crab bolt with bent
-washer for the other. Unless the fastenings can be kept always tight,
-the above arrangement makes a very noisy, clattering road, as there
-are so many metal surfaces in contact, and so little to deaden the
-vibration. For narrow flange rails carrying heavy rolling load, chairs
-may be necessary to increase the bearing surface on the sleeper, but
-with rails having flanges five inches wide and upwards, it is better
-to let the flange rest direct on the wood of a properly grooved
-sleeper, and thus obtain a smoother and less noisy road.</p>
-
-<p>On exceptionally sharp curves, wrought-iron or steel tie-bars, as in
-<a href="#fig320">Fig. 335</a>, are sometimes used to maintain the line to gauge. They may
-be made out of bars 3 inches wide by ½ an inch thick,
-<!--237.png--><a name="Page_225" id="Page_225"></a><span class="pagenum">[Pg 225]</span>
-turned over at
-the ends to grip the outside flanges. Being made to exact template,
-they have to be threaded on to the rails before spiking down, and are
-placed between the sleepers at distances from 7 to 10 feet apart.</p>
-
-<p class="p2"><strong>Laying Permanent Way.</strong>&mdash;To preserve a good line and level to the
-permanent way, it is absolutely necessary that the road-bed should be
-kept thoroughly drained. If provision be not made for quickly carrying
-away the rain-water, and if it be allowed to collect under and around
-the sleepers, the action of the passing trains will work the finer
-particles of the packing into the consistency of soft mud, which will
-be gradually squeezed away, leaving the sleepers imperfectly supported
-and insecure. A loose sleeper involves a depression in the rails, and
-a corresponding lurch in the vehicles of the train, and a series of
-these depressions may produce such an oscillation in the train as to
-cause it to leave the rails.</p>
-
-<p>The height or space from formation-level to rail-level is generally
-about 1 foot 9 inches for a flange railroad, and about 2 feet for a
-chair railroad.</p>
-
-<p><a href="#fig336">Figs. 336 and 337</a> show cross-sections of both descriptions of road as
-laid down for a double line in cutting. The same arrangement applies
-to similar roads laid down in embankment, merely omitting the
-side-drains or water-tables. The bottom layer of ballast or road-bed
-should consist of good hard, quarried, or broken stones, each 6 inches
-deep, set on edge, firmly and closely hand-packed, forming a
-foundation through which the rain-water can be quickly carried away.
-On the top of this bottom pitching should be placed a 6-inch layer of
-broken stone ballast or strong clean gravel, of which none of the
-stones should be larger than will pass through a 2-inch ring. When the
-sleepers and rails have been laid on this second layer, and properly
-packed to line and level, the top ballasting, or boxing, of either
-broken stones or strong clean gravel, should be filled in to the form
-and extent specified. Where broken stones are used for the top
-ballasting none of them should be larger than will pass through a
-1½-inch ring.</p>
-
-<p>Broken stone ballast should only be made from the hardest and soundest
-description of rock or boulders, so that, however small the particles,
-they will remain sharp and clean.</p>
-
-<div class="figcenter">
- <a name="fig336"></a>
- <img src="images/i226.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures"
- title="Figure 336 through 344"
- />
-</div>
-
-<p>There are many kinds of rock which appear hard and compact when first
-excavated, but upon exposure to the weather
-<!--238.png--><!--239.png--><a name="Page_227" id="Page_227"></a><span class="pagenum">[Pg 227]</span>
-undergo a complete change,
-developing into soft masses containing too much clay to allow the
-water to pass through readily. Where rock is scarce and gravel
-plentiful, the lower layer may be made of the heavier or coarser
-gravel, leaving the finer gravel for the upper layer, or boxing; but
-there is no doubt that the broken stone pitching makes the most
-efficient bottom layer. No gravel ballast should be used which is not
-free from clay or earthy sand.</p>
-
-<p>Wherever there are particles of earthy matter, sufficient to furnish
-nourishment for vegetable growth, weeds will quickly spring up, and
-once established are most difficult, if not impossible, to eradicate.
-The presence of weeds checks drainage, and gives an untidy appearance
-to the line, besides constantly occupying a large portion of the
-platelayers’ time in their removal.</p>
-
-<p>Clean cinders, free from dust or earth, are much used for upper
-ballast and boxing, and being lighter than gravel, are specially
-applicable for soft boggy ground. Burnt clay, broken into small
-pieces, has been largely adopted in districts where both rock and
-gravel were difficult to obtain. Chalk, furnace-slag broken small,
-crushed brick and sand, are frequently used as ballast. Sand is
-objectionable where there is high-speed traffic, as the finer
-particles rise in the form of dust and deposit themselves on the
-vehicles and machinery of the train.</p>
-
-<p>The water-tables, or side drains in the cuttings, should be cut below
-the formation level, and to a depth or width sufficient to take away
-all rain-water, or water arising from springs. Where the material of
-the cutting is of a loose friable nature, it may be necessary to
-protect the sides of the water-tables with low dry stone walls, as in
-<a href="#fig336">Fig. 338</a>; or glazed earthenware pipes may be laid, as in <a href="#fig336">Fig. 339</a>,
-with open joints, or with grate openings at regular intervals. In some
-cases substantial side-walls and invert are requisite to carry away
-the flow of water.</p>
-
-<p>Timber sleepers intended for the flange railroad should have the
-rail-seats grooved by machinery to ensure perfect accuracy in the
-position of the grooves, and in the angle or inclination of the
-rail-seats. <a href="#fig336">Fig. 340</a> is a side view of part of a sleeper grooved to
-receive a flange rail. The presence of the grooves materially
-facilitate the laying of the rails to gauge, but must not be allowed
-to interfere with the constant use of the platelayer’s gauge. In a
-similar manner the timber sleepers for the
-<!--240.png--><a name="Page_228" id="Page_228"></a><span class="pagenum">[Pg 228]</span>
-chair road frequently have
-the spike-holes bored to template by machinery, as indicated on <a href="#fig336">Fig.
-341</a>. Steel or iron sleepers are delivered with the recesses for rails,
-and holes for bolts or fastenings formed complete by machinery.</p>
-
-<p>The distances apart of the sleepers will be regulated in a great
-measure by the weight of the rails and the description of the traffic.
-Where light rails are intended to carry heavy engines the sleepers
-must be laid closer together than would be necessary for heavy rails.
-The joint being the weakest part of the rail, it is usual to put the
-sleepers closer together at that place, with a view to gain additional
-support, to assist the fish-plates in preserving as much as possible a
-firm unyielding surface at the rail-joint.</p>
-
-<p><a href="#fig336">Fig. 343</a> shows an arrangement of sleepering largely adopted for steel
-flange rails 26 feet long, and weighing 79 lbs. per yard. The length
-of a rail is more a question of convenience of handling, facility of
-transhipment, and general use, than of actual manufacture. There is no
-difficulty in rolling rails up to 50 feet in length, or more; but very
-long rails are extremely ungainly things to move about, and are more
-exposed to receive permanent bends or kinks in unloading, besides
-requiring greater spaces at the joints to allow for contraction and
-expansion.</p>
-
-<p><a href="#fig336">Fig. 344</a> is an example of sleepering for a chair railroad, for steel
-bull-head rails 26 feet long, and weighing 85 pounds per yard.</p>
-
-<p>Line stakes and level pegs must be put in at suitable distances to
-guide the platelayers in laying the rails to the correct line and
-level, and on the curves the proper amount must be marked off for the
-super-elevation of the outer rail.</p>
-
-<p>When the second layer of ballast has been spread for its full width
-and depth the sleepers can be distributed, and the rails or chairs
-spiked down to the correct gauge. Before putting on the fish-plates
-spaces must be left at the ends of the rails to allow for contraction
-and expansion, the amount depending upon the temperature at the time
-of laying down the rails. As the rails will expand, or increase in
-length, with the heat, it is necessary to allow more space for
-expansion for rails laid down in the cold, or winter months. On our
-home railways rails are very rarely laid down when the temperature is
-lower than 25° F., or higher than 125° F., and this range of 100° may
-be considered as covering all the variations likely to occur in
-ordinary practice. The greater portion of the permanent-way
-<!--241.png--><a name="Page_229" id="Page_229"></a><span class="pagenum">[Pg 229]</span>
-laying is
-carried on when the temperature is between 40° and 75°. The results of
-very carefully conducted experiments show that an increase of
-temperature of 1° F. will cause an iron or steel bar, or rail, to
-expand or lengthen to the extent of seven one-millionths of its
-length. Working this out for a range of 100° F. would give an increase
-in length of seven hundred one-millionths, which would be equal to an
-extension of 0·2184 of an inch in a 26-foot rail. For our home
-railways, therefore, a space of 5/16 of an inch will be found amply
-sufficient to meet the variations in length between the extremes of
-winter and summer, for a rail from 26 feet to 30 feet in length. Too
-much allowance for expansion is detrimental to the rails, because
-where the spaces are excessively large the wheels drop into the hollow
-and hammer or spread the ends of the rails.</p>
-
-<p>The fish-bolts should not be completely tightened up until the
-permanent way is thoroughly set, and packed to its finished line and
-level.</p>
-
-<p>On straight line the rail-joints should be laid square and opposite to
-each other. Permanent-way laying with broken joints is rarely adopted,
-except on curves or station-yards.</p>
-
-<p>On curves the joints of the inner rails gain on the joints of the
-outer rails to the extent <span style="white-space:nowrap;">of&mdash;</span></p>
-
-<p class="center"><span class="top_bottom larger"><span class="top u">radius + gauge</span><span class="bottom">radius</span></span>
- × length of rail.</p>
-
-<p>The amount of this gain, or lead, is adjusted by cutting off a portion
-of the end of the inner rails at certain intervals.</p>
-
-<p>Assuming the fish-bolt holes to be spaced as shown on <a href="#fig336">Fig. 342</a>, then,
-when the inner rail is leading to the extent of 2 inches, a piece 4
-inches long is cut off, as shown by dotted lines, leaving the original
-second fish-bolt hole to serve as first or end fish-bolt hole, and a
-new or second bolt-hole is drilled by hand at A. This method sets back
-the joint 2 inches from the square, and the lead is allowed to go on
-again until it becomes necessary to cut off another piece of 4 inches.
-Another mode is to have a proportion of the rails rolled 2 or 3 inches
-shorter for use on the curves.</p>
-
-<p>On curves of a 1000 feet radius and upwards, the rails should be laid
-to the normal gauge, but on curves of lesser radius the gauge may be
-slightly increased, and as much as ¾ of an inch allowed on a curve of
-500 feet radius.</p>
-
-<p><!--242.png--><a name="Page_230" id="Page_230"></a><span class="pagenum">[Pg 230]</span>
-The amount of cant, or super-elevation, to be given to the outer rail
-on curves must be regulated by the speed of the train and the gauge of
-the line. Many formulæ have been compiled to determine the necessary
-amount of super-elevation, but experience has shown that by some of
-them the calculated amounts were excessive. Possibly during past years
-too much cant has been given in many cases. The following simple
-formula approaches very closely to practical <span style="white-space:nowrap;">experience&mdash;</span></p>
-
-<table summary="formula" class="smaller">
-<tr><td class="center smaller"><span class="top_bottom larger"><span class="top u">(velocity in miles per hour)<sup>2</sup> × gauge in feet</span>
-<span class="bottom">radius in feet × 1·25 </span></span></td>
-<td class="center">=</td>
-<td class="leftb">the super-elevation of outer rail in inches.</td>
-</tr>
-</table>
-
-<p>For high-speed trains uniformity of cant is of the utmost importance,
-more so even than the exact amount. Any irregularity in the
-super-elevation of the outer rail, sometimes high and sometimes low,
-will produce a dangerous swaying movement in the train, which, if not
-promptly checked, would lead to derailment.</p>
-
-<p>More injury is done to curves by spreading, arising from rigid
-wheel-bases of engines and tenders, than from any want of
-counteraction to centrifugal force.</p>
-
-<p>When a long length of permanent way has been linked in, rails spiked
-to gauge, and fish-plates bolted together, the platelayers can proceed
-to the final adjustment to line and level in accordance with the
-stakes and pegs provided for their guidance. The setting to exact line
-is effected by means of long pointed round iron crowbars, which are
-struck forcibly into the ballast alongside the rails, and serve as
-powerful hand-levers to pull or push the rails to the right or left as
-directed by the foreman standing some distance back at one of the
-line-stakes. The men with the crowbars pass from rail-length to
-rail-length, until a long stretch of road has been pulled into correct
-line.</p>
-
-<p>The adjustment to rail-level is done by first packing up the sleepers
-to the correct height at the various level-pegs, and then packing up
-the intermediate sleepers so that the surface of the top of the rails
-forms one uniform even line from level-peg to level-peg. On new lines
-it is usual to pack a little high in the first instance to allow for
-the subsidence or compression which invariably takes place on the
-passage of heavy trains over fresh ballast.</p>
-
-<p>The form or contour line of the top ballast will vary
-<!--243.png--><a name="Page_231" id="Page_231"></a><span class="pagenum">[Pg 231]</span>
-according to
-circumstances. In station-yards it is usual to fill in the ballast
-almost up to the level of the top of the rails for the convenience and
-safety of the men who are constantly moving about marshalling the
-carriages and waggons. Out on the open line between stations, the
-ballast on some railways is filled in up to rail-level, while on
-others it is only filled in up to the tops of the sleepers, leaving
-the rails and chairs quite clear of the ballast. On others, again, the
-ballast is filled well up to the rails and channelled in the centre,
-as shown on the sketches <a href="#fig336">Figs. 336 and 337</a>. Channelling the centre of
-the road reduces the quantity of ballast per mile, ensures good
-drainage, and also stability by not permitting any central support to
-the sleepers. By covering up the lower table and sides of rails the
-noise is reduced to a minimum, vibration is absorbed, and a more
-silent road is the result. The contact with the ballast also preserves
-the rail from the extremes of temperature. Where the ballasting is not
-channelled there is some risk of the sleepers breaking in the middle.
-The constant packing of the sleepers just under the rails has a
-tendency to drift some of the ballast inwards towards the middle of
-the sleeper, forming a hard compact mass, and this mass, acting as
-fulcrum, throws considerable strain on the middle of the sleeper when
-the trains pass over and depress the ends. Where the ballast is filled
-in level with the rails on top of sleepers it should be loosened
-occasionally in the middle to prevent it becoming too hard.</p>
-
-<p>Connections with the rails of the main line will have to be made in
-various forms to suit the circumstances of the joining lines or
-sidings.</p>
-
-<p><a href="#fig345">Fig. 345</a> shows a simple double-line junction.</p>
-
-<div class="figcenter">
- <a name="fig345"></a>
- <img src="images/i232.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 345 through 356"
- title="Figures 345 through 356"
- />
-</div>
-
-<p><a href="#fig345">Fig. 346</a> shows an example of what is termed a <em>flying junction</em>, or a
-junction of two double lines arranged in such a manner as to cause the
-least interruption to a constant train traffic passing <span class="muchsmaller">UP</span> and
-<span class="muchsmaller">DOWN</span> over both lines. Upon referring to <a href="#fig345">Fig. 345</a> it will be seen
-that a train from <strong>F</strong>, turning off at the points <strong>E</strong> and proceeding to
-<strong>G</strong>, must block, or close for traffic the section <strong>ABC</strong> during its
-passage over that line towards <strong>G</strong>. With a crowded train-service the
-blocking of both <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> main lines for the working of one
-train would cause much interruption, and to obviate such delay the
-<em>flying junction</em> is substituted. <a href="#fig345">Fig. 346</a> shows how a train from <strong>F</strong>
-is turned off at the points <strong>J</strong> and proceeds on to <strong>K</strong>, where by means
-of a bridge
-<!--244.png--><!--245.png--><a name="Page_233" id="Page_233"></a><span class="pagenum">[Pg 233]</span>
-it passes either over or under both main lines, and
-continues on to <strong>G</strong> without in any way interfering with the train
-service on <strong>ABC</strong>.</p>
-
-<p><a href="#fig345">Fig. 347</a> is an ordinary plain siding or <em>turn-out</em>, including the
-necessary throw-off or trap-points and short dead end.</p>
-
-<p><a href="#fig345">Fig. 348</a> is an ordinary <em>cross-over road</em> from <span class="muchsmaller">DOWN</span> main line to
-<span class="muchsmaller">UP</span> main line, and <i lang="la">vice versâ</i>.</p>
-
-<p><a href="#fig345">Fig. 349</a> is a double cross-over road, generally termed a <em>scissors</em>
-cross-over.</p>
-
-<p><a href="#fig345">Fig. 350</a> is a simple through cross-over road from <span class="muchsmaller">DOWN</span> main line
-to siding alongside <span class="muchsmaller">UP</span> main line.</p>
-
-<p><a href="#fig345">Fig. 351</a> is a similar arrangement of through cross-over road with the
-addition of a pair of slip points at <strong>S</strong> to make a connection with the
-<span class="muchsmaller">UP</span> main line, thus combining the facilities of the ordinary
-cross-over and through cross-over road.</p>
-
-<p><a href="#fig345">Fig. 352</a> shows a set of three throw-switches with all the sliding
-tongues placed side by side; and <a href="#fig345">Fig. 353</a> shows another arrangement of
-three throws with the sliding-rails of the second set of switches
-placed just behind the heel of the first set of switches. The latter
-method works very well where there is sufficient length for the
-purpose.</p>
-
-<p><a href="#fig345">Fig. 354</a> shows a square crossing, where one line of railway crosses
-another line of railway on the same level.</p>
-
-<p><a href="#fig345">Fig. 355</a> shows a connection with a siding by means of an ordinary
-carriage or waggon turn-table.</p>
-
-<p><a href="#fig345">Fig. 356</a> shows a set of “runaway” points which are sometimes placed in
-the main line at the top of an incline close to a station, the object
-being to intercept or throw off any portion of a train which may have
-become detached, and which would, if unchecked, run away back down the
-incline. By means of a weighted lever or spring the points are set to
-the normal position of <em>open</em> to the siding, and as they are
-“trailing” points for the running road they are readily closed by a
-passing train. One or other of the above forms of connections, or a
-combination of them, will meet all the requirements which usually
-occur in railway work.</p>
-
-<p><a href="#fig357">Fig. 357</a> is an enlarged sketch of an ordinary cross-over road, and
-<a href="#fig357">Fig. 358</a> of a double or <em>scissors</em> cross-over.</p>
-
-<div class="figcenter">
- <a name="fig357"></a>
- <img src="images/i234.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 357 and 358"
- title="Figures 357 and 358"
- />
-</div>
-
-<p><a href="#fig359">Fig. 359</a> shows a <em>single-slip</em> point connection, and <a href="#fig359">Fig. 360</a> a
-<em>double-slip</em> point connection. In places where slip connections can
-be introduced they add greatly to the facilities for train
-<!--246.png--><!--247.png--><a name="Page_235" id="Page_235"></a><span class="pagenum">[Pg 235]</span>
-movements
-without curtailing the available standing-room for vehicles on the
-lines and sidings. They are simple in construction, do not require
-crossings, and in many cases save a complete cross-over road. At the
-same time slip connections can only be laid down where the angle of
-the intersecting lines is sufficiently flat to admit of a connecting
-curve of workable radius.</p>
-
-<p><a href="#fig361">Fig. 361</a> is an enlarged sketch of a set of ordinary 15-foot switches
-or points. By placing them about the middle of the stock rails the
-joints of the latter are kept well beyond the sliding rails, and the
-road is held firmly together. It is necessary to place the sleepers
-closer together at the switches to allow for the reduction in section
-of the sliding rails, which results from planing them down to the
-requisite shape. By substituting two long timbers for the ordinary
-sleepers at the points of the switch rails, as shown on the sketch, a
-more efficient support is obtained for the switch-box or crank in the
-case of rod-worked switches, and the working distance from the rails
-is accurately maintained, irrespective of any packing or pulling of
-the road. In the sketch a steel bull-head rail is shown on one side,
-and a steel flange rail on the other, each bolted to an ordinary
-cast-iron switch chair. Switch chairs are sometimes made of plates of
-wrought-iron or steel, forged to the correct shape, and riveted
-together. They are, however, much more costly than cast-iron chairs,
-and deteriorate more quickly from corrosion.</p>
-
-<div class="figcenter">
- <a name="fig359"></a>
- <img src="images/i236.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 359 and 360"
- title="Figures 359 and 360"
- />
-</div>
-
-<p><a href="#fig361">Fig. 362</a> is an enlarged sketch of an ordinary crossing similar to the
-one indicated at <strong>C</strong> (<a href="#fig359">Fig. 359</a>), and composed of a cast-steel
-reversible block. The ends and lugs, <strong>L</strong>, <strong>L</strong>, are formed to suit the
-connecting rails and fish-plates, as shown in the cross-sections. The
-casting is secured to the crossing timbers by bolts passing through
-the side lugs, <strong>S</strong>, a cast-iron packing-washer, <strong>W</strong>, being placed
-between the lug and the timber to ensure a solid seat and avoid
-rocking. A very important point in the construction of these block
-crossings is to have the groove or flange-path sufficiently deep to
-prevent the striking or touching of the flange of a much-worn tyre. A
-well-made, carefully annealed steel-block reversible crossing is very
-smooth in the road, and has a long life. It is all in one solid piece;
-there are no parts to work loose or spread; the wear of the running
-surface is very uniform, and when the one side is much worn down,
-there is the other ready for service. The writer has had many of these
-steel-block
-<!--248.png--><!--249.png--><a name="Page_237" id="Page_237"></a><span class="pagenum">[Pg 237]</span>
-reversible crossings in use under heavy and fast traffic
-for six and eight years without turning.</p>
-
-<p><a href="#fig361">Fig. 363</a> shows an ordinary crossing made of steel bull-head rails
-secured in strong cast-iron chairs; and <a href="#fig361">Fig. 364</a> is a similar crossing
-made of steel flange rails. In some cases the two rails forming the
-<strong>V</strong> are welded together at the point <strong>B</strong>, and in others they are
-riveted or bolted together. <a href="#fig361">Fig. 365</a> shows a diamond or through
-crossing similar to the one indicated at <strong>D</strong>, <a href="#fig359">Fig. 359</a>, made of steel
-bull-head rails and chairs.</p>
-
-<p>Crossings are constructed in a variety of forms, whether on the
-principle of the cast-steel block, or made out of ordinary steel
-rails; and the above sketches merely illustrate some well-recognized
-types which experience has proved to be efficient and durable in the
-road. The angles of the crossings will depend upon the divergence of
-the intersecting lines to be connected; ordinary crossings, to the
-angle of 1 in 10, work in for very general use in station-yards, but
-many are required of angles varying from 1 in 6 to 1 in 14, and in
-some cases 1 in 16.</p>
-
-<p>As a rule, engineers endeavour as far as possible to avoid using
-ordinary crossings flatter than 1 in 12, or diamond crossings flatter
-than 1 in 9, because the gap between the running rails becomes very
-considerable beyond those angles. At the same time, there are many
-cases of ordinary crossings of 1 in 16, and diamond crossings of 1 in
-12 and 1 in 13 laid down in exceptional places, and which have carried
-heavy and fast traffic for many years. All crossings should be well
-protected with wing rails and guard rails, as shown on the sketches.</p>
-
-<p><a href="#fig366">Fig. 366</a> illustrates a method of bringing the UP and down lines of a
-double line of railway close to each other, and passing them over a
-single-line opening bridge, or a bridge where the works for the second
-line have not been completed. This arrangement avoids the necessity of
-any switches, and prevents any accidents which would arise from a
-misplaced switch. Each set of trains is effectually kept to its own
-line of rails. With proper signalling or pilot working, the
-double-line traffic can be worked over the single-line bridge without
-difficulty. The writer has adopted the above arrangement in many cases
-when renewing double-line bridges or viaducts where the width for
-traffic working has been restricted to half of the bridge.</p>
-
-<div class="figcenter">
- <a name="fig361"></a>
- <img src="images/i238.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 361 through 365"
- title="Figures 361 through 365"
- />
-</div>
-
-<p>In some instances the same system has been extended to the
-<!--250.png--><!--251.png--><a name="Page_239" id="Page_239"></a><span class="pagenum">[Pg 239]</span>
-carrying of
-four lines of rails over a double-line bridge, as shown on <a href="#fig366">Fig. 367</a>.</p>
-
-<p>The principal tool used by platelayers for lifting the permanent way
-is a long iron-shod wooden lever, as shown in <a href="#fig366">Fig. 368</a>. The point of
-the lower end is pushed under the sleeper, and the curved shoulder
-placed on a large stone or piece of wood as a support, and then by
-pulling down the upper end of the lever the road can be lifted to the
-height required. Screw lifting-jacks of various kinds are also used
-for the same purpose, the foot or base of the jack resting on the
-ballast, while the claws grasp the under side of the rail, and raise
-it by means of the screw. With appliances which lift by the rails, the
-sleepers have to be raised by the holding power of the spikes or
-bolts, an operation which is apt to throw undue strain on spikes.
-Where possible it is preferable to lift from the under side of the
-sleepers.</p>
-
-<p>Beaters similar to the one shown on <a href="#fig366">Fig. 369</a> are used for packing the
-ballast. One end of the beater is pointed like a pick, and serves to
-loosen the ballast or broken stone, and the other end is made somewhat
-in the hammer-head form to pack or beat the ballast under the sleeper.
-With skilled men the beater is a most useful tool, speedy and
-effective in its action. Held in both hands, it is raised slightly,
-and then brought down sharply, the hammer-head striking the gravel or
-broken stone placed alongside for packing under the sleeper. A series
-of smart blows can be given with rapidity and without requiring any
-great muscular effort. In some foreign countries there is difficulty
-in initiating the natives to work with the ordinary beater, on account
-of the stooping position necessary for its use. To meet this
-difficulty the writer has in many cases substituted a packing or
-tamping bar, as shown in <a href="#fig366">Fig. 370</a>. This bar, about 5 feet long, is
-made of light round wrought-iron or steel, with a ring-shaped handle
-at one end, and an ordinary beater head at the other. The workman
-using this bar stands upright, guides the bar, held loosely, with his
-left hand, and with his right gives a continuance of smart blows. This
-tool works well in the hands of light active natives, who can thus
-give a number of rapid strokes without much exertion.</p>
-
-<div class="figcenter">
- <a name="fig366"></a>
- <img src="images/i240.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 366 through 372"
- title="Figures 366 through 372"
- />
-</div>
-
-<p>The simple rail-bender, or <em>Jim Crow</em>, of the form shown in <a href="#fig366">Fig. 371</a>,
-is much used by platelayers for giving a slight bend or set to rails
-which have to be laid down on sharp curves on main line or cross-over
-roads. The rail is laid across the two arms,
-<!--252.png--><!--253.png--><a name="Page_241" id="Page_241"></a><span class="pagenum">[Pg 241]</span>
-and the screw turned round
-and downwards by means of an iron bar lever used as a spanner or
-wrench to the nut shown on the sketch. The same tool is also
-serviceable for straightening rails which have become crooked or
-kinked. Large and more comprehensive machines are used for bending
-rails in large quantities or setting them to exact curvature, but,
-being heavy and cumbersome, they are rarely taken away from the
-store-yards.</p>
-
-<p>Strong steel shovels of the form shown in <a href="#fig366">Fig. 372</a> are the most
-suitable for platelayers’ general use when working with gravel, sand,
-or broken stones.</p>
-
-<p>For driving iron spikes and wooden keys in cast-iron chairs a
-long-handled hammer is the most convenient for work, and its long
-swinging action produces considerable force without much actual
-labour.</p>
-
-<p>Road-gauges, nut-wrenches, short straight-edges, spirit-levels,
-ratchet-drills, augurs, and cold setts of well-tempered steel for
-cutting rails, are all required by the men engaged in laying permanent
-way.</p>
-
-<p>The following summaries give the estimated cost of materials alone for
-one mile of steel bull-head rail and steel flange rail permanent way
-of different weights. The 90-lb. steel bull-head rail is at present
-the heaviest of that section laid down to any extent on our home
-railways, and the chairs and fastenings are made heavy to correspond
-to the rail and the traffic for which it is intended. As the rails in
-the summaries become lighter, the weights of the chairs and fastenings
-are decreased. As yet there are not many samples of the 100-lb. steel
-flange rail; but in those places where it has been laid down it has
-been supported with a liberal supply of sleepers, to obtain increased
-bearing surface. With a 5½-inch flange, and a rectangular sleeper 10
-inches wide, the bearing surface on the wood is only about 55 square
-inches, as compared with about 100 square inches, the bearing surface
-of a large cast-iron chair for a heavy bull-head rail. As previously
-explained, a small bearing surface on a sleeper tends to the cutting
-down into the wood, and rendering the sleeper unsafe and useless even
-before it has become unserviceable from decay: hence the reason for
-ample bearing surface on the sleeper. The last two summaries refer to
-3-foot narrow-gauge lines. In more than one instance the 45-lb. rails
-first laid down have been found much too light for the engines
-required to work the traffic, and when
-<!--254.png--><a name="Page_242" id="Page_242"></a><span class="pagenum">[Pg 242]</span>
-making extensions of the system
-65-lb. rails have been adopted. Indeed, when taking into consideration
-the weight of most of the narrow-gauge engines, generally from 24 to
-28 tons in working order, and their short wheel-base, it would appear
-that a 65-lb. rail is the minimum which should be used both for
-stability and economy in maintenance.</p>
-
-<p>The summaries are prepared from examples in actual use, and represent
-the number and weight of sleepers, chairs, and fastenings in each
-instance. Even with the same weight of rail, the practice differs on
-various lines as to the weights of the chairs and fastenings; and the
-selections have been made to show a fair average. On some railways the
-chairs are secured partly by tree-nails and partly by spikes, or crab
-bolts; on others only spikes are used. The prices put down are the
-estimated values of the materials delivered into the Permanent Way
-Stores of our own home railways, and are exclusive of all costs of
-freight, carriage, or distribution to the site of laying down. The
-prices are only comparative, and fluctuate up or down according to the
-current value of the raw materials from which the various items are
-manufactured. Lighter rails and smaller fastenings cost more per ton
-than those of a heavier type, as they involve more labour and
-workmanship.</p>
-
-<div class="chapter nothandheld">
-<table summary="cost of steel rails at 90 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Bull-head Rails (90 lbs. per Yard).</span><br />
-       <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td><td class="right t">qrs.</td>
-    <td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 90&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">141</td><td class="rightm">8</td><td class="rightm">2</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">707</td><td class="rightm">2</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 41&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">43</td><td class="rightm">17</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">6</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="centernobox l" colspan="4">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">404</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4224 cast-iron chairs, each 50 lbs.</td>
-    <td class="rightm l">94</td><td class="rightm">5</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">330</td><td class="rightm">0</td><td class="rightm">1</td>
-</tr>
-<tr><td class="lefthnobox">8448 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">15</td><td class="rightm">2</td><td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">37</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8448 tree-nails, at per 1000</td>
-    <td class="centernobox l" colspan="4">&mdash;</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">29</td><td class="rightm">11</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox b">4224 oak keys, at per 1000</td>
-    <td class="centernobox l b" colspan="4">&mdash;</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">21</td><td class="rightm b">2</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="right r b" colspan="8">£</td><td class="right b">1589</td><td class="right b">10</td>
-    <td class="right b">10</td>
-</tr>
-</table>
-</div><!--end 90 lb table-->
-
-<div class="chapter handheld">
-<table summary="cost of steel rails at 90 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Bull-head Rails (90 lbs. per Yard).</span><br />
-       <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td><td class="right t">qrs.</td>
-    <td class="right t">lbs.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 90&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">141</td><td class="rightm">8</td><td class="rightm">2</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 41&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="centernobox l" colspan="4">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4224 cast-iron chairs, each 50 lbs.</td>
-    <td class="rightm l">94</td><td class="rightm">5</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8448 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">15</td><td class="rightm">2</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8448 tree-nails, at per 1000</td>
-    <td class="centernobox l" colspan="4">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox b">4224 oak keys, at per 1000</td>
-    <td class="centernobox l b" colspan="4">&mdash;</td>
-</tr>
-</table>
-</div><!--end 90 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="cost of steel rails at 90 lbs per yard, part 2">
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="3">Price.</td>
-    <td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 90&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">707</td><td class="rightm">2</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 41&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">43</td><td class="rightm">17</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">6</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">404</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4224 cast-iron chairs, each 50 lbs.</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">330</td><td class="rightm">0</td><td class="rightm">1</td>
-</tr>
-<tr><td class="lefthnobox">8448 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">37</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8448 tree-nails, at per 1000</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">29</td><td class="rightm">11</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox b">4224 oak keys, at per 1000</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">21</td><td class="rightm b">2</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="right r b" colspan="4">£</td><td class="right b">1589</td><td class="right b">10</td>
-    <td class="right b">10</td>
-</tr>
-</table>
-</div><!--end 90 lb table, part 2-->
-
-<p class="p2 break">
-<!--255.png--><a name="Page_243" id="Page_243"></a><span class="pagenum">[Pg 243]</span></p>
-
-<div class="chapter nothandheld">
-
-<table summary="bull-head rails at 85 lbs per yard">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Bull-head Rails (85 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td><td class="right t">qrs.</td>
-    <td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 85&nbsp;lbs. per yard (26-ft. length )</td>
-    <td class="rightm l">134</td><td class="rightm">0</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">670</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 38&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">17</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">46</td><td class="rightm">9</td><td class="rightm">10</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 45&nbsp;lbs.</td>
-    <td class="rightm l">81</td><td class="rightm">11</td><td class="rightm">1</td><td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">285</td><td class="rightm">9</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">12</td><td class="rightm">2</td><td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">36</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">4</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">0</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1477</td>
-    <td class="rightm b">11</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 85 lb table-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 85 lbs per yard, part 1">
-<tr><td colspan="5"><p class="center"><span class="sc">Steel Bull-head Rails (85 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td><td class="right t">qrs.</td>
-    <td class="right t">lbs.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 85&nbsp;lbs. per yard (26-ft. length )</td>
-    <td class="rightm l">134</td><td class="rightm">0</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 38&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">17</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 45&nbsp;lbs.</td>
-    <td class="rightm l">81</td><td class="rightm">11</td><td class="rightm">1</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">12</td><td class="rightm">2</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-</tr>
-</table>
-</div><!--end 85 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 85 lbs per yard, part 2">
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="3">Price.</td>
-    <td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 85&nbsp;lbs. per yard (26-ft. length )</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">670</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 38&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">46</td><td class="rightm">9</td><td class="rightm">10</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 45&nbsp;lbs.</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">285</td><td class="rightm">9</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">36</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">4</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">0</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1477</td>
-    <td class="rightm b">11</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 85 lb table, part 2-->
-
-<div class="chapter nothandheld">
-
-<table summary="bull-head rails at 80 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Bull-head Rails (80 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 80&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">125</td><td class="rightm">14</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">628</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">45</td><td class="rightm">6</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 40&nbsp;lbs.</td>
-    <td class="rightm l">72</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">253</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">12</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">36</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">4</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">20</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td>
-    <td class="rightm l b">1403</td><td class="rightm b">3</td><td class="rightm b">7</td>
-</tr>
-</table>
-</div><!--end 80 lb table-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 80 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Bull-head Rails (80 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 80&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">125</td><td class="rightm">14</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 40&nbsp;lbs.</td>
-    <td class="rightm l">72</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">12</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-</tr>
-</table>
-</div><!--end 80 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 80 lbs per yard, part 2">
-<tr><td class="t b"></td><td class="centernobox t l" colspan="3">Price.</td>
-    <td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-
-<tr><td class="lefthnobox">Steel bull-head rails, 80&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">628</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">45</td><td class="rightm">6</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 40&nbsp;lbs.</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">253</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">36</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 tree-nails, at per 1000</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">4</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">20</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="5">£</td>
-    <td class="rightm l b">1403</td><td class="rightm b">3</td><td class="rightm b">7</td>
-</tr>
-</table>
-</div><!--end 80 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="bull-head rails at 75 lbs per yard">
-<tr><td colspan="11"><p class="p2 center break"><span class="sc">Steel Bull-head Rails (75 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 75&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">117</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">585</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 35&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">7</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">42</td><td class="rightm">17</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 37&nbsp;lbs.</td>
-    <td class="rightm l">67</td><td class="rightm">1</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">234</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">12,180 iron cup-headed spikes</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">54</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-    <td class="rightm l">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">20</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td>
-    <td class="rightm l b">1342</td><td class="rightm b">2</td><td class="rightm b">5</td>
-</tr>
-</table>
-</div><!--end 75 lb table-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 75 lbs per yard, part 1">
-<tr><td colspan="11"><p class="p2 center break"><span class="sc">Steel Bull-head Rails (75 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 75&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">117</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 35&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">7</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 37&nbsp;lbs.</td>
-    <td class="rightm l">67</td><td class="rightm">1</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">12,180 iron cup-headed spikes</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-</tr>
-</table>
-</div><!--end 75 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 75 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 75&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">585</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 35&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">42</td><td class="rightm">17</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">15</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 37&nbsp;lbs.</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">234</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">12,180 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">54</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td class="rightm l b">5</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">20</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td>
-    <td class="rightm l b">1342</td><td class="rightm b">2</td><td class="rightm b">5</td>
-</tr>
-</table>
-</div><!--end 75 lb table, part 2-->
-
-<p class="p2 break">
-<!--256.png--><a name="Page_244" id="Page_244"></a><span class="pagenum">[Pg 244]</span></p>
-
-<div class="chapter nothandheld">
-<table summary="bull-head rails at 70 lbs per yard">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Bull-head Rails (70 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 70&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">110</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">550</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 32&nbsp;lbs. per pair</td>
-    <td class="rightm l">5</td><td class="rightm">16</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">39</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">2</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 34&nbsp;lbs.</td>
-    <td class="rightm l">61</td><td class="rightm">12</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">215</td><td class="rightm">13</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">3</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-    <td class="rightm l b">4</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">18</td><td class="rightm b">5</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1257</td>
-    <td class="rightm b">19</td><td class="rightm b">4</td>
-</tr>
-</table>
-</div><!--end 70 lb table-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 70 lbs per yard, part 1">
-<tr><td colspan="5"><p class="center"><span class="sc">Steel Bull-head Rails (70 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 70&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">110</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 32&nbsp;lbs. per pair</td>
-    <td class="rightm l">5</td><td class="rightm">16</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">2</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 34&nbsp;lbs.</td>
-    <td class="rightm l">61</td><td class="rightm">12</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">3</td><td class="rightm">3</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-</tr>
-</table>
-</div><!--end 70 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 70 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 70&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">550</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 32&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">39</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 34&nbsp;lbs.</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">215</td><td class="rightm">13</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td class="rightm l b">4</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">18</td><td class="rightm b">5</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1257</td>
-    <td class="rightm b">19</td><td class="rightm b">4</td>
-</tr>
-</table>
-</div><!--end 70 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="bull-head rails at 65 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Bull-head Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 65&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">536</td><td class="rightm">5</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 28&nbsp;lbs. per pair</td>
-    <td class="rightm l">5</td><td class="rightm">1</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">10</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">1</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">13</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">304</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 28&nbsp;lbs.</td>
-    <td class="rightm l">50</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">4</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">203</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">2</td><td class="rightm">19</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">10</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">19</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-    <td class="rightm l b">4</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">4</td><td class="rightm b">9</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1140</td>
-    <td class="rightm b">3</td><td class="rightm b">6</td>
-</tr>
-</table>
-</div><!--end 65 lb table-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 65 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Bull-head Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 65&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 28&nbsp;lbs. per pair</td>
-    <td class="rightm l">5</td><td class="rightm">1</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">1</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 28&nbsp;lbs.</td>
-    <td class="rightm l">50</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">2</td><td class="rightm">19</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td colspan="4" class="centernobox l b">&mdash;</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="bull-head rails at 65 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel bull-head rails, 65&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">536</td><td class="rightm">5</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 28&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">10</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">13</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">304</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">4060 cast-iron chairs, each 28&nbsp;lbs.</td>
-    <td class="rightm l">4</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">203</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">8120 iron cup-headed spikes</td>
-    <td class="rightm l">10</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">19</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">4060 oak keys, at per 1000</td>
-    <td class="rightm l b">4</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">4</td><td class="rightm b">9</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1140</td>
-    <td class="rightm b">3</td><td class="rightm b">6</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 100 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (100 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 100&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">157</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">785</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 42&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">12</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">42</td><td class="rightm">18</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">2464 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">472</td><td class="rightm">5</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">8448 dog-head spikes</td>
-    <td class="rightm l">3</td><td class="rightm">6</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">41</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">18</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1380</td>
-    <td class="rightm b">14</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 100 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 100 lbs per yard, part 1">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (100 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 100&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">157</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 42&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">12</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2464 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">8448 dog-head spikes</td>
-    <td class="rightm l">3</td><td class="rightm">6</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 100 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 100 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 100&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">785</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 42&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">42</td><td class="rightm">18</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">2464 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">472</td><td class="rightm">5</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">8448 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">41</td><td class="rightm">5</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">18</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1380</td>
-    <td class="rightm b">14</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 100 lb table, part 2-->
-
-<p class="p2 break">
-<!--257.png--><a name="Page_245" id="Page_245"></a><span class="pagenum">[Pg 245]</span></p>
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 79 lbs per yard">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Flange Rails (79 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 79&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">125</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">625</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">43</td><td class="rightm">12</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">6</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">6496 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">10</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">10</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">19</td><td class="rightm b">4</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1130</td>
-    <td class="rightm b">14</td><td class="rightm b">2</td>
-</tr>
-</table>
-</div><!--end 79 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 79 lbs per yard, part 1">
-<tr><td colspan="5"><p class="center"><span class="sc">Steel Flange Rails (79 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 79&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">125</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">4</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">6496 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">10</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">10</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 79 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 79 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 79&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">625</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 37&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">43</td><td class="rightm">12</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">15</td><td class="rightm">6</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2030 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">389</td><td class="rightm">1</td><td class="rightm">8</td>
-</tr>
-<tr><td class="lefthnobox">6496 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">19</td><td class="rightm b">4</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1130</td>
-    <td class="rightm b">14</td><td class="rightm b">2</td>
-</tr>
-</table>
-</div><!--end 79 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 74 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (74 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 74&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">116</td><td class="rightm">5</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">581</td><td class="rightm">8</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 30½&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">15</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">2</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">1</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">7</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, &nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">371</td><td class="rightm">1</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">9</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">18</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1050</td>
-    <td class="rightm b">11</td><td class="rightm b">7</td>
-</tr>
-</table>
-</div><!--end 74 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 74 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Flange Rails (74 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 74&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">116</td><td class="rightm">5</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 30½&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">15</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">1</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, &nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">9</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 74 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 74 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 74&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">581</td><td class="rightm">8</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 30½&nbsp;lbs. per pair</td>
-    <td class="rightm l">6</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">31</td><td class="rightm">2</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">12</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">7</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, &nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">371</td><td class="rightm">1</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">18</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1050</td>
-    <td class="rightm b">11</td><td class="rightm b">7</td>
-</tr>
-</table>
-</div><!--end 74 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 65 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">561</td><td class="rightm">16</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">371</td><td class="rightm">1</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">9</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm b l">1029</td>
-    <td class="rightm b">13</td><td class="rightm b">5</td>
-</tr>
-</table>
-</div><!--end 65 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 65 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Flange Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">9</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 65 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">561</td><td class="rightm">16</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">1936 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">371</td><td class="rightm">1</td><td class="rightm">4</td>
-</tr>
-<tr><td class="lefthnobox">6336 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">18</td><td class="rightm">9</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm b l">1029</td>
-    <td class="rightm b">13</td><td class="rightm b">5</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 2-->
-
-<p class="p2 break">
-<!--258.png--><a name="Page_246" id="Page_246"></a><span class="pagenum">[Pg 246]</span></p>
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 60 lbs per yard">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Flange Rails (60 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 60&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">94</td><td class="rightm">5</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">518</td><td class="rightm">11</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 25&nbsp;lbs. per pair</td>
-    <td class="rightm l">3</td><td class="rightm">18</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">28</td><td class="rightm">9</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">404</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">34</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">1021</td>
-    <td class="rightm b">6</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 60 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 60 lbs per yard, part 1">
-<tr><td colspan="5"><p class="center"><span class="sc">Steel Flange Rails (60 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 60&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">94</td><td class="rightm">5</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 25&nbsp;lbs. per pair</td>
-    <td class="rightm l">3</td><td class="rightm">18</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">8</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">6</td><td class="rightm b">3</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 60 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 60 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 60&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">518</td><td class="rightm">11</td><td class="rightm">7</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 25&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">28</td><td class="rightm">9</td><td class="rightm">2</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 10&nbsp;in. × 5&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">10</td>
-    <td class="rightm l">404</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">34</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">16</td><td class="rightm b">14</td><td class="rightm b">5</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">1021</td>
-    <td class="rightm b">6</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 60 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 50 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (50 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 50&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">78</td><td class="rightm">11</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">451</td><td class="rightm">16</td><td class="rightm">1</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 22&nbsp;lbs. per pair</td>
-    <td class="rightm l">3</td><td class="rightm">9</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">25</td><td class="rightm">19</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">0</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">316</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">7</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">6</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">4</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">2</td>
-    <td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">13</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">14</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">856</td>
-    <td class="rightm b">2</td><td class="rightm b">3</td>
-</tr>
-</table>
-</div><!--end 50 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 50 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Flange Rails (50 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line.</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 50&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">78</td><td class="rightm">11</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 22&nbsp;lbs. per pair</td>
-    <td class="rightm l">3</td><td class="rightm">9</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">0</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">7</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">6</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">1</td><td class="rightm b">2</td>
-    <td class="rightm b">0</td><td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 50 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 50 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 50&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">451</td><td class="rightm">16</td><td class="rightm">1</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 22&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">25</td><td class="rightm">19</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2112 creosoted sleepers, 9&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm l">316</td><td class="rightm">16</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7040 dog-head spikes</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">4</td><td class="rightm">7</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">13</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">14</td><td class="rightm b">6</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">856</td>
-    <td class="rightm b">2</td><td class="rightm b">3</td>
-</tr>
-</table>
-</div><!--end 50 lb table, part 2-->
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 65 lbs per yard">
-<tr><td colspan="11"><p class="p2 center"><span class="sc">Steel Flange Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge).</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">561</td><td class="rightm">16</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2288 creosoted sleepers, 6&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">2</td><td class="rightm">3</td>
-    <td class="rightm l">257</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7744 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">17</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">12</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">7</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">1</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">2</td><td class="rightm b">2</td><td class="rightm b">0</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">26</td><td class="rightm b">5</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">929</td>
-    <td class="rightm b">17</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 65 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 65 lbs per yard, part 1">
-<tr><td colspan="5"><p class="p2 center"><span class="sc">Steel Flange Rails (65 lbs. per Yard).</span><br />
-    <i>Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge).</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">102</td><td class="rightm">3</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">4</td><td class="rightm">4</td><td class="rightm">3</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">1</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2288 creosoted sleepers, 6&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">7744 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">17</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">7</td><td class="rightm">2</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">2</td><td class="rightm b">2</td><td class="rightm b">0</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 65 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 65&nbsp;lbs. per yard (30-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">561</td><td class="rightm">16</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 27&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm l">30</td><td class="rightm">14</td><td class="rightm">5</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2288 creosoted sleepers, 6&nbsp;ft. × 9&nbsp;in. × 4½&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">2</td><td class="rightm">3</td>
-    <td class="rightm l">257</td><td class="rightm">8</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">7744 dog-head spikes</td>
-    <td class="rightm l">12</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">12</td><td class="rightm">6</td>
-</tr>
-<tr><td class="lefthnobox">704 fang clips</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">1</td><td class="rightm">3</td>
-</tr>
-<tr><td class="lefthnobox b">1408 crab bolts</td>
-    <td class="rightm l b">12</td><td class="rightm b">10</td><td class="rightm b">0</td>
-    <td class="rightm l b">26</td><td class="rightm b">5</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">929</td>
-    <td class="rightm b">17</td><td class="rightm b">8</td>
-</tr>
-</table>
-</div><!--end 65 lb table, part 2-->
-
-<p class="p2 center break">
-<!--259.png--><a name="Page_247" id="Page_247"></a><span class="pagenum">[Pg 247]</span></p>
-
-<div class="chapter nothandheld">
-<table summary="steel flange rails at 45 lbs per yard">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Flange Rails (45 lbs. per Yard).</span><br />
-     <i>Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge).</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 45&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">70</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">5</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">406</td><td class="rightm">12</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 16&nbsp;lbs. per pair</td>
-    <td class="rightm l">2</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">7</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">21</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">0</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2233 creosoted sleepers, 6&nbsp;ft. × 8&nbsp;in. × 4&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-    <td class="rightm l">0</td><td class="rightm">1</td><td class="rightm">10</td>
-    <td class="rightm l">204</td><td class="rightm">13</td><td class="rightm">10</td>
-</tr>
-<tr><td class="lefthnobox">7308 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">14</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">2</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">0</td><td class="rightm b">18</td><td class="rightm b">0</td>
-    <td class="rightm b">0</td>
-    <td class="rightm l b">13</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">11</td><td class="rightm b">14</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="8">£</td><td class="rightm l b">695</td>
-    <td class="rightm b">9</td><td class="rightm b">10</td>
-</tr>
-</table>
-</div><!--end 45 lb table-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 45 lbs per yard, part 1">
-<tr><td colspan="11"><p class="center"><span class="sc">Steel Flange Rails (45 lbs. per Yard).</span><br />
-     <i>Estimated Cost of Materials for One Mile of Single Line (3-ft. gauge).</i></p></td>
-</tr>
-<tr><td class="t b"></td><td class="centernobox t l" colspan="4">Weight per mile of single line.</td>
-</tr>
-<tr><td></td><td class="right t l">tons.</td><td class="right t">cwt.</td>
-    <td class="right t">qrs.</td><td class="right t">lbs.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 45&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">70</td><td class="rightm">14</td><td class="rightm">1</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 16&nbsp;lbs. per pair</td>
-    <td class="rightm l">2</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">0</td><td class="rightm">18</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2233 creosoted sleepers, 6&nbsp;ft. × 8&nbsp;in. × 4&nbsp;in.</td>
-    <td colspan="4" class="centernobox l">&mdash;</td>
-</tr>
-<tr><td class="lefthnobox">7308 dog-head spikes</td>
-    <td class="rightm l">2</td><td class="rightm">14</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">0</td><td class="rightm">5</td><td class="rightm">0</td>
-    <td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">0</td><td class="rightm b">18</td><td class="rightm b">0</td>
-    <td class="rightm b">0</td>
-</tr>
-</table>
-</div><!--end 45 lb table, part 1-->
-
-<div class="chapter handheld">
-<table summary="steel flange rails at 45 lbs per yard, part 2">
-<tr><td class="t b"></td>
-    <td class="centernobox t l" colspan="3">Price.</td><td class="centernobox t l" colspan="3">Amount.</td>
-</tr>
-<tr><td></td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-    <td class="centernobox t l">£</td><td class="centernobox t">s.</td><td class="centernobox t">d.</td>
-</tr>
-<tr><td class="lefthnobox">Steel flange rails, 45&nbsp;lbs. per yard (26-ft. lengths)</td>
-    <td class="rightm l">5</td><td class="rightm">15</td><td class="rightm">0</td>
-    <td class="rightm l">406</td><td class="rightm">12</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Steel fish-plates (deep), 16&nbsp;lbs. per pair</td>
-    <td class="rightm l">7</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">21</td><td class="rightm">15</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">Fish-bolts and nuts</td>
-    <td class="rightm l">13</td><td class="rightm">10</td><td class="rightm">0</td>
-    <td class="rightm l">12</td><td class="rightm">3</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">2233 creosoted sleepers, 6&nbsp;ft. × 8&nbsp;in. × 4&nbsp;in.</td>
-    <td class="rightm l">0</td><td class="rightm">1</td><td class="rightm">10</td>
-    <td class="rightm l">204</td><td class="rightm">13</td><td class="rightm">10</td>
-</tr>
-<tr><td class="lefthnobox">7308 dog-head spikes</td>
-    <td class="rightm l">13</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">35</td><td class="rightm">2</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox">812 fang clips</td>
-    <td class="rightm l">14</td><td class="rightm">0</td><td class="rightm">0</td>
-    <td class="rightm l">3</td><td class="rightm">10</td><td class="rightm">0</td>
-</tr>
-<tr><td class="lefthnobox b">1624 crab bolts</td>
-    <td class="rightm l b">13</td><td class="rightm b">0</td><td class="rightm b">0</td>
-    <td class="rightm l b">11</td><td class="rightm b">14</td><td class="rightm b">0</td>
-</tr>
-<tr><td class="rightm b" colspan="4">£</td><td class="rightm l b">695</td>
-    <td class="rightm b">9</td><td class="rightm b">10</td>
-</tr>
-</table>
-</div><!--end 45 lb table, part 2-->
-</div><!--end chapter three-->
-
-<div class="chapter">
-<!--260.png--><a name="Page_248" id="Page_248"></a><span class="pagenum">[Pg 248]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER IV.</h3>
-
-<p class="center smaller">Stations: Station Buildings, Roofs, Lines, and Sidings.</p>
-
-<p class="p2"><strong>Stations.</strong>&mdash;When selecting a site for a station, not only should due
-regard be paid to the proximity and convenience of access to the town
-or place to be served, but attention should be given to the gradients
-of the line near the proposed station. If it can possibly be avoided,
-a station should not be placed in a hollow at the foot of two
-inclines, as such a position would always entail heavy work starting
-trains on the ascending gradients, with the risk of sliding back into
-the station again in unfavourable weather; and for arriving trains
-there would be increased difficulty in properly controlling the
-vehicles on the descending gradients so as to bring them to a stand in
-the event of any sudden stoppage being required. With stations on a
-summit, having gradients falling in each direction, the starting
-trains can get away more readily, and the arriving trains have the
-benefit of the rising gradient to assist them in coming to a stand.
-Possibly the best selection would be a long length of level, both in
-the station proper and for a considerable distance on each side; but
-it is not often that such a combination can be obtained without
-incurring extra expenditure. The station-yard itself should, however,
-be on the level, or as nearly so as possible, for the convenience and
-safety of marshalling or shunting carriages or waggons. No siding
-should be laid on such a gradient as would render it possible for
-vehicles to start into motion during high winds. Carriages and waggons
-having good oil axle-boxes will start themselves on a gradient of 1 in
-300 under the influence of a moderately strong breeze, and a slight
-push will start them on a gradient of 1 in 400.</p>
-
-<p>The number and arrangement of the lines, sidings, platforms, loading
-banks, and other conveniences of a station, will depend upon the
-description and amount of traffic to be accommodated.
-<!--261.png--><a name="Page_249" id="Page_249"></a><span class="pagenum">[Pg 249]</span>
-There is a wide
-range from the simple village station, with its one short siding, to
-the great city terminus, with its labyrinth of lines and sidings, and
-its groups of platforms, offices, warehouses, and other accessories.
-Each station should be laid out with a view to meet the special
-requirements of the principal traffic likely to arise, whether
-passenger, timber, coal, stone, cattle, or general merchandise, and
-ample space should be retained to permit further enlargement and
-additional sidings at any future time. If provision is not made for
-the latter in the outset it will certainly lead to large expenditure
-at some later date. Land adjoining a railway station is quickly
-appropriated by the public on account of its proximity and convenience
-for conveyance, and soon covered with store-yards, warehouses, and
-other buildings, and when any portion of these have to be acquired for
-station enlargements, they can only be obtained at a large cost, very
-often ten times as much as the value of the original ground.</p>
-
-<p>When laying out approach roads to goods or passenger stations, whether
-intermediate or terminal, due importance should be given to the
-advantage of making them wide, easy in gradient, and fairly straight.
-A narrow, crooked access to a busy goods yard is a great impediment to
-the expeditious working of a heavy traffic; and road waggons conveying
-long pieces of timber or ironwork along such a route, would be very
-apt to block the roadway and delay the passage of other vehicles. A
-steep gradient will prevent the carriers taking full loads, and will
-add to the cost and time of delivery.</p>
-
-<div class="figcenter">
- <a name="fig373"></a>
- <img src="images/i250.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 373"
- title="Figure 373"
- />
-</div>
-
-<p>An approach road to a large passenger station should be laid out with
-a long frontage to a wide footpath to enable the numerous intending
-passengers to alight conveniently from the conveyances which bring
-them to the station. A portion of the footpath and carriage-way in
-front of the entrance to the booking-hall should be covered over with
-a light roof to provide shelter during inclement weather. The footpath
-should be on the same level as the vestibule or booking-hall, so that
-the public may pass at once to the ticket-office and their luggage be
-wheeled on hand-barrows direct to the platform or luggage-room. Every
-effort should be made to avoid introducing steps from the footpath to
-the booking-hall, as they check the proper ingress of the passengers,
-and are very severe on elderly persons and invalids, besides
-necessitating the dilatory method of carrying each piece of the
-<!--262.png--><!--263.png--><a name="Page_251" id="Page_251"></a><span class="pagenum">[Pg 251]</span>
-passengers’ luggage by hand. Experience has shown the inconvenience of
-steps to be so great that in many cases a large expenditure has
-afterwards been incurred to do away with them, and bring the
-setting-down footpath to the same level as the booking-hall. For a
-large station the booking-hall should be spacious and well provided
-with separate ticket windows for the different classes of passengers
-and districts of the line; and the access or communication with the
-platform should be ample and free from obstruction. Small doors and
-narrow passage-ways check the movements of the passengers and create
-confusion and delay.</p>
-
-<p>Waiting-rooms for the different classes of passengers,
-inquiry-offices, luggage-rooms, lavatories, etc., will have to be
-provided according to the amount of traffic to be accommodated. In
-large stations it may be necessary to have two or more groups of such
-rooms to suit the different sets of platforms.</p>
-
-<p>At the most important terminal stations of our home railways it is
-usual to lay down the main-line arrival platforms with a cab or
-carriage rank alongside, so that the passengers alighting from the
-railway carriages have merely to walk across the platforms, and step
-into the cabs or vehicles waiting to take them and their luggage away
-from the station. This arrangement is not only a great convenience to
-the passengers, but expedites the clearing of the platform and the
-making way for another incoming train. It would not, however, be of
-any service on continental lines, or other foreign railways, where all
-arriving luggage must first be taken to the general luggage room, to
-be examined by the local customs, or <em>octroi</em> officers, before being
-allowed to pass out of the station.</p>
-
-
-<div class="figcenter">
- <a name="fig374"></a>
- <img src="images/i252.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 374 and 375"
- title="Figure 374 and 375"
- />
-</div>
-
-<p>Main-line departure platforms should be of ample width to allow of the
-free movement of the passengers, ticket examiners, officials, and men
-wheeling passengers’ luggage. The accommodation should not only be
-sufficient for the normal traffic, but allowance should be made for
-the large crowds which may assemble for excursion trains during the
-holiday season or other occasions of national gathering. Additional or
-local platforms, frequently termed <em>dock platforms</em>, may be required
-for suburban trains, and may be made narrower in width, and without
-cab ranks, as the passengers using them only travel short distances
-and rarely have more luggage than they carry in their hands. These
-dock platforms are generally made available for
-<!--264.png--><!--265.png--><a name="Page_253" id="Page_253"></a><span class="pagenum">[Pg 253]</span>
-outgoing as well as
-incoming trains. The lengths of the main-line or local platforms will
-be regulated by the number of carriages forming a train.</p>
-
-<p><a href="#fig373">Fig. 373</a> is a diagram sketch of a large terminal passenger station,
-with main and local platforms as above described. It is merely typical
-to illustrate the principle, and may be multiplied and varied to any
-extent in the way of lines and platforms. In the sketch the main
-groups of offices, waiting-rooms, etc., are shown at the end of the
-station; but they may be equally well placed at the side, as their
-actual location is principally a question of proximity or convenience
-of access to some main street or thoroughfare. The lower or
-platform-level rooms of such a building are mainly devoted to the
-public for booking-offices, waiting-rooms, refreshment-rooms,
-lavatories, offices for parcels, telegraph and inquiry, suitable rooms
-being set apart for lamps, foot-warmers, guards, and porters. Above
-this lower story a range of offices can be built for the use of the
-principal officers and staff of the different departments of the
-company.</p>
-
-<p><a href="#fig374">Fig. 374</a> is a plan of a small terminal station on a single line of
-railway, where the passenger traffic is small, and one platform is
-made to serve alternately both for arrival and departure trains. The
-booking-hall, waiting-rooms, offices, etc., are laid down parallel to
-the line of rails, and the approach road and footpath are parallel to
-the building. The platform roof extends to the outer wall, and
-provides shelter for the passengers on the platform, and forms a shed
-for the carriages at night.</p>
-
-<p><a href="#fig374">Fig. 375</a> is a sketch of an intermediate or roadside station on a
-single line of railway. All the offices, waiting-rooms, etc., are on
-one platform, which serves for trains travelling in either direction.
-The dotted lines show the additions which would be necessary to make
-the station a stopping-place for trains working in opposite
-directions.</p>
-
-<p><a href="#fig376">Fig. 376</a> shows an ordinary intermediate or roadside station on a
-double line of railway, with two passenger platforms, and a connection
-between them either by subway or over-line footbridge. The principal
-offices and waiting-rooms are shown on the one side, and only small
-waiting-rooms, etc., on the other.</p>
-
-
-<div class="figcenter">
- <a name="fig376"></a>
- <img src="images/i254.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 376"
- title="Figure 376"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig377"></a>
- <img src="images/i255.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 377 and 378"
- title="Figures 377 and 378"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig379"></a>
- <img src="images/i256.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 379 and 380"
- title="Figures 379 and 380"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig381"></a>
- <img src="images/i257.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 381 and 382"
- title="Figures 381 and 381"
- /></div>
-
-<p><a href="#fig377">Fig. 377</a> is a sketch of a double-line intermediate or roadside
-station at the junction of a small single-line branch railway.
-Branch-line passengers to and from the main <span class="muchsmaller">DOWN</span>-line trains
-merely walk across the platform to get into their respective
-<!--266.png-->
-<!--267.png-->
-<!--268.png-->
-<!--269.png-->
-<!--270.png--><a name="Page_258" id="Page_258"></a><span class="pagenum">[Pg 258]</span>
-trains,
-and those to or from the main <span class="muchsmaller">UP</span> trains walk across the
-footbridge or subway to get to the opposite platform.</p>
-
-<p><a href="#fig377">Fig. 378</a> is a plan of a double-line roadside station, with two
-main-line passenger platforms and a dock line and platform for the use
-of local or branch-line trains. This arrangement is applicable where
-the actual junction with the main line is at a little distance from
-the station, but not sufficiently far away to warrant an additional
-junction station as shown in <a href="#fig377">Fig. 377</a>.</p>
-
-<p><a href="#fig379">Fig. 379</a> shows a similar roadside station laid out with a more
-comprehensive arrangement of dock-lines and platforms. The lines
-alongside the main passenger platforms are <em>turn-outs</em> from the
-main-line proper, and leave the latter free for the passage of fast
-through trains or goods trains when an ordinary passenger train is
-standing alongside the platform. In this way a fast non-stopping train
-can overtake and be sent forward in advance of a slow passenger train.</p>
-
-<p><a href="#fig379">Fig. 380</a> shows a roadside station with two double platforms, the inner
-lines and platforms being reserved for main-line passenger trains, and
-the outer lines for branch-line trains. By this arrangement carriages
-can be quickly transferred from a branch-line train to a main-line
-train, and <i lang="la">vice versâ</i>; access from the public road, or from one
-platform to the other, can be obtained either by subway or over-line
-footbridge.</p>
-
-<p><a href="#fig381">Fig. 381</a> is a sketch plan of an island platform for a double-line
-roadside station, near which there are junctions with two branch
-lines. The <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> main lines run alongside the wide
-portion of the platform, and the branch lines run into the two dock
-platforms. The waiting-rooms, refreshment-rooms, etc., are placed in
-groups on the wide platform, spaces being left between the blocks for
-the convenience of access from side to side. The booking-office and
-parcels-office are placed alongside the approach road on the higher
-level. An over-line footbridge extends from the booking-hall to the
-dock platforms, terminating with steps on one side and an inclined
-ramp of 1 in 8 on the other. In carrying out the above plan for a
-railway on an embankment, the access from the booking-hall to the
-platform would be provided by a subway instead of an over-line
-footbridge.</p>
-
-<p><a href="#fig381">Fig. 382</a> shows another form of island platform, also arranged for
-<span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> main-line trains, and two branch-line trains. The
-access is obtained from a public-road over-line
-<!--271.png--><a name="Page_259" id="Page_259"></a><span class="pagenum">[Pg 259]</span>
-bridge crossing the
-railway, and the booking-office is placed at the top of an incline, or
-ramp, leading down to the platform. The dock-line platforms are
-arranged different to those in the preceding example, with the object
-of providing longer platforms for the main-line trains. This result,
-however, is obtained at some little inconvenience to the dock-line
-trains, as the passengers from one of these must walk round a portion
-of two platforms to get into the other dock-line train, instead of
-merely walking across the platform as in <a href="#fig381">Fig. 381</a>.</p>
-
-<p>In some cases of island platforms the total width of the station
-buildings and platforms is made much greater than indicated in the
-above sketches, and a wide, easy incline constructed from an over-line
-public-road bridge, to allow cabs and carriages to come down to a
-large paved area between the platforms, for the convenience of setting
-down and taking up the train passengers and their luggage.</p>
-
-<p>The island-platform arrangement possesses many advantages for the
-exchange of passenger traffic. All the platforms are connected and on
-one level, and passengers, together with their luggage, can be quickly
-transferred from one train to another. One set of waiting-rooms,
-refreshment-rooms, etc., are sufficient, and are available for the
-passengers of all the four trains. A smaller number of station men are
-required for the work, as the staff can be more concentrated and
-better utilized than when there are separate platforms on opposite
-sides of the line.</p>
-
-<p>The number, size, and arrangement of waiting-rooms and other offices
-for the public at a large station will depend upon the amount and
-description of traffic to be dealt with at the particular station
-under consideration. Where the passenger traffic is to a large extent
-of a local or short distance character, a moderate amount of
-waiting-room space may be sufficient, as these local passengers
-regulate their arrival so as to avoid waiting any great length of time
-for the trains. An enormous suburban passenger traffic is carried on
-in many places with a very limited waiting-room accommodation, the
-frequency of the trains and the routine of the travellers reducing the
-necessity of such rooms to a minimum. A more ample waiting-room space
-will be necessary when providing for a large, long journey, or through
-traffic, and for stations at seaports, as the intending passengers,
-particularly those landing from steamers, generally reach the station
-a considerable time before the departure of the
-<!--272.png--><a name="Page_260" id="Page_260"></a><span class="pagenum">[Pg 260]</span>
-trains to take them
-forward. For this class of traffic it will also be necessary to
-provide suitable refreshment-rooms. At large terminal stations it is
-frequently found more convenient for the working of the traffic to
-have two or more sets of waiting-rooms, etc., separating the local and
-long-journey passengers, and placing the rooms alongside the
-corresponding platforms.</p>
-
-<p>Lavatories and conveniences at large stations should be provided on a
-liberal scale, and fitted up in the most substantial and efficient
-manner. Not only should they be thoroughly well ventilated, but they
-should have abundance of light. Nothing tends so much to ensure order
-and cleanliness in these places as plenty of light.</p>
-
-<p>It will frequently be found that at many of the large important
-stations there are local surroundings and circumstances of level and
-foundations, which will to a great extent influence the arrangement of
-the rooms and offices to be devoted to the public service. No fixed or
-standard type could be adopted for all cases. Each one will have to be
-studied out to suit the locality, and the grouping must be made to
-work in with the best facilities obtainable. In all such cases one of
-the principal points is to select a convenient position for the
-booking-hall, easy of access to all persons entering the station
-premises. On no account should the ticket-office be placed in a
-position tending to block the thoroughfare on to the platforms. A
-large number of intending passengers may already be in possession of
-tickets, and the station arrangements should enable these passengers
-to proceed at once to the platforms without having to struggle or
-force their way through crowds of other passengers gathered round the
-ticket windows. In some instances it is found expedient to provide
-auxiliary booking-offices for excursion traffic, to be used only on
-special occasions, thus restricting the principal booking-offices to
-the ordinary main-line booking.</p>
-
-<p>When laying out small intermediate or roadside stations for either
-double or single line, or small terminal stations on short branch
-lines in thinly populated districts, it becomes a question how to
-provide the requisite statutory accommodation with a minimum amount of
-building. The following sketches taken from actual examples may be of
-use for reference.</p>
-
-<p><a href="#fig383">Fig. 383</a> shows the smallest size of station building that can very
-well be constructed to be of any practical service. It comprises an
-office for the station-master, who has to attend to
-<!--273.png--><a name="Page_261" id="Page_261"></a><span class="pagenum">[Pg 261]</span>
-the tickets,
-parcels, and telegraph; a waiting-hall with glazed front; a small
-waiting-room and <span class="muchsmaller">W.C.</span> for ladies; and a yard with conveniences for
-gentlemen, coal store, etc. Access to the station is obtained through
-a gateway in the platform fencing.</p>
-
-<p><a href="#fig383">Fig. 384</a> shows a somewhat similar arrangement, but with two additional
-rooms. The road approach to the station is brought alongside and
-parallel to the building, and access to the platform is obtained by
-passing through the booking-hall, which has a glazed front to the
-line.</p>
-
-<p><a href="#fig383">Fig. 385</a> gives the particulars of a building containing rather more
-accommodation than the two preceding examples.</p>
-
-<p><a href="#fig386">Fig. 386</a> shows a small terminal station for a short branch line where
-there is a moderate tourist traffic during the season. In addition to
-the regular station accommodation, a refreshment-room is added for the
-convenience of those passengers who have to drive into the country, or
-have arrived at the station by road conveyance. The platform roof,
-which is extended out over the line of rails, as shown on the
-transverse section, forms a complete covering for the platform, and
-serves for a carriage-shed at night.</p>
-
-<p>The above sketches merely illustrate types of some small stations
-suitable for home or colonial lines, and may be built of stone, brick,
-concrete, iron, or timber. For towns of more importance, the offices
-and rooms would have to be increased both in number and size. On
-foreign lines it is customary to provide an office and large hall
-fitted up with counters for the use of the Local Excise Authorities in
-the examination of passengers’ luggage; and at some stations one or
-more rooms have to be set apart for the use of the military
-authorities.</p>
-
-<p>Narrow platforms should always be avoided, especially in front of the
-offices and waiting-rooms. Nothing tends more to check the proper
-expeditious working of the traffic than a confined space for the
-movement of the passengers and of the station staff carrying luggage.</p>
-
-
-<div class="figcenter">
- <a name="fig383"></a>
- <img src="images/i262.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 383, 384, 385"
- title="Figure 383, 384, 385"
- />
-</div>
-
-
-<div class="figcenter">
- <a name="fig386"></a>
- <img src="images/i263.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 386"
- title="Figure 386"
- />
-</div>
-
-<p>In cases where the traffic will warrant the expenditure, it will be
-found an advantage to construct a light roof or verandah over a
-portion of the platforms of roadside stations. This covering will
-provide a convenient shelter for the passengers and their luggage, and
-prevent the crowding of booking-halls and doorways during inclement
-weather. In hot countries a verandah or awning of some description on
-the platforms is an absolute
-<!--274.png-->
-<!--275.png-->
-<!--276.png--><a name="Page_264" id="Page_264"></a><span class="pagenum">[Pg 264]</span>
-necessity, and those travellers who have
-had any experience of railways under a tropical sun, will call to mind
-the celerity with which the passengers seek such welcome shade.</p>
-
-<p>A very important item in the construction of a large terminal station
-is the roof over the lines and platforms. Wrought-iron and steel can
-now be obtained in so many convenient sections, and at such moderate
-prices, that timber-framed roofs, except for very small spans, are now
-rarely used for railway work. The metallic structure is much lighter
-in appearance and more durable, besides being less exposed to
-destruction by fire. The introduction of iron and steel has enabled
-roofs to be constructed of very much larger spans than would have been
-prudent to have attempted in timber; at the same time it must be kept
-in mind that, notwithstanding this increased facility of construction,
-the cost of a roof per relative area covered increases very rapidly as
-the span increases. The extent of space to be roofed over in some of
-our modern terminal stations is so large that the question of
-roof-spans to be adopted has to be considered very carefully. It has
-been argued by some that if the area be divided out into small or
-moderate spans, the presence of the rows of columns for supporting the
-roof might preclude the possibility of any future re-location of the
-lines and platforms except by an entire rearrangement of the
-roof-work. On the other hand, it may also be stated that railway
-engineers have now obtained such a thorough experience of the
-necessary relative proportions of platforms and carriage-lines for
-large stations, as to enable them to lay out these works without any
-risk of requiring alterations for many years.</p>
-
-<div class="figcenter">
- <a name="fig387"></a>
- <img src="images/i265.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 387 through 393"
- title="Figures 387 through 393"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig394"></a>
- <img src="images/i266.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 394 through 398 "
- title="Figures 394 through 398 "
- />
-</div>
-
-<div class="figcenter">
- <a name="fig399"></a>
- <img src="images/i267.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 399 through 402"
- title="Figures 399 through 402 "
- />
-</div>
-
-<div class="figcenter">
- <a name="fig403"></a>
- <img src="images/i268.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 403 through 405 "
- title="Figures 403 through 405"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig406"></a>
- <img src="images/i269.jpg"
- width="auto" height="100%"
- alt="Illustration: Figure 406"
- title="Figure 406"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig407"></a>
- <img src="images/i270.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 407 through 410 "
- title="Figures 407 through 410"
- />
-</div>
-
-<p>There are so many descriptions of roof-principals used in railway
-stations that it would be impossible here to introduce more than a few
-examples. <a href="#fig387">Figs. 387 to 405</a> illustrate by diagram sketches a series of
-types taken from actual practice. <a href="#fig406">Fig. 406</a> gives more in detail the
-particulars of the roof-principal of 60 feet span, <a href="#fig387">Fig. 392</a>. As will
-be noted from <a href="#fig406">Fig. 406</a>, the width of 120 feet between the walls is
-divided into two spans of 60 feet each, the ends of the principals in
-the centre of the 120 feet being carried on arched wrought-iron
-girders of 48 feet span, supported on strong ornamental cast-iron
-columns placed at 48-foot centres. The rain-water from the large
-centre gutter is taken down inside the columns and conveyed away to
-drainage pipes laid down for the purpose. The 60-foot principal above
-<!--277.png-->
-<!--278.png-->
-<!--279.png-->
-<!--280.png-->
-<!--281.png-->
-<!--282.png-->
-<!--283.png--><a name="Page_271" id="Page_271"></a><span class="pagenum">[Pg 271]</span>
-described forms a very strong roof, and is light in cost and
-maintenance. The weight of ironwork, both wrought and cast, in the
-principals, arched wrought-iron girders, cast-iron columns, centre
-gutters, etc., is only 0·51 of a ton per square (of 100 square feet)
-of area covered. For comparison, the weight of ironwork in the roof,
-<a href="#fig399">Fig. 402</a>, of 198 feet span is 1·42 ton per square of area covered; and
-of the roof, <a href="#fig403">Fig. 404</a>, of 210 feet span, is 2·07 tons per square.</p>
-
-<p>This increase in weight per square as the spans go on increasing
-results, not only in a much larger outlay for original construction,
-but entails also a proportionally heavier expenditure for maintenance
-and painting. The item of painting alone is an expensive one in all
-iron-roof work, and must be attended to regularly for the proper
-protection and appearance of the ironwork. With the smaller spans, the
-roof-trusses form very convenient supports for painters’ scaffolding
-or planking, but with the very large spans the greater height and the
-form of the roof-principals render specially designed scaffolding and
-appliances necessary for the painting and repairs.</p>
-
-<p>Doubtless there is something very attractive about a large span roof,
-its bold outline stretching from side to side of a wide covered area
-imparts an imposing effect which cannot be claimed for smaller or more
-moderate spans; but where roofs are constructed for purely utilitarian
-purposes it becomes a question worthy of grave consideration whether a
-series of smaller spans would not provide the same practical benefits
-as would be obtained from one very large span. Upon referring to the
-typical sketch of a terminal station, <a href="#fig373">Fig. 373</a>, it will be seen that
-the total width from inside to inside of main walls is 240 feet. The
-lines and platforms are so arranged that by placing rows of columns at
-<strong>A</strong>, <strong>A</strong>, <strong>B</strong>, <strong>B</strong>, and <strong>C</strong>, <strong>C</strong>, the entire width may be divided out
-into four spans of 60 feet; or, if preferred, a row of columns at
-<strong>B</strong>, <strong>B</strong> may be adopted, resulting in two spans of 120 feet, or the
-entire width may be included in one large span of 240 feet. Any one of
-the three arrangements will provide an effectual roof-covering, and
-the selection must be decided by the cost or expediency.</p>
-
-<p>Another way to avoid the introduction of large span-roof principals,
-and to preserve the covered area free from intervening columns, is to
-erect strong truss-girders extending across at right angles from the
-main walls. These truss-girders are placed at
-<!--284.png--><a name="Page_272" id="Page_272"></a><span class="pagenum">[Pg 272]</span>
-suitable distances, and
-carry simple roof-principals of convenient spans. In some cases the
-roof-principals are placed as shown in <a href="#fig407">Figs. 407 and 408</a>, and in
-others as in <a href="#fig407">Fig. 409</a>.</p>
-
-<p>In another system the roof-principals are incorporated with the main
-truss-girders, as in <a href="#fig407">Fig. 410</a>.</p>
-
-<p>With the above type of covering the truss-girders take the place of
-the arched wrought-iron girders and cast-iron columns, as illustrated
-in <a href="#fig406">Fig. 406</a>, but will be more costly, as may be gathered from the
-following brief comparison: Assuming the area to be covered as 480
-feet long and 180 feet wide, then the width of 180 feet could be
-divided into three spans of 60 feet each, or one centre span of 65
-feet, and two of 57 feet 6 inches if they would work in more
-conveniently. With columns at 48-foot centres longitudinally, the
-three-span arrangement would contain the following:&mdash;Twenty cast-iron
-columns in the two rows, or twenty-two columns if two columns are
-placed side by side at the extreme end; 960 lineal feet of light
-arched wrought-iron girders in twenty girders of 48 feet span.</p>
-
-<p>On the other hand, with the truss-girders placed at 40-foot centres to
-suit roof-principals resting on the tops of girders, as shown in <a href="#fig407">Fig.
-409</a>, or to suit the arrangement shown in <a href="#fig407">Fig. 407</a>, there would be
-twelve heavy truss-girders, each of 180 feet span, making a total
-length of 2160 lineal feet of deep truss-girder work, exclusive of
-about another 60 lineal feet, which would be required for the bearings
-on the side walls.</p>
-
-<p>The successful lighting by day of a large roofed-in station will
-depend principally upon an appropriate distribution of the glazed
-portions. With a large span, and the glass skylights placed near the
-apex, the side lines and platforms will be much less efficiently
-lighted than those near the centre; and again, if the glazed parts are
-only at the sides, then the centre portion will be rather in the
-shade. Where possible it is better to place the glazed portions and
-slated portions alternately, so as to obtain a more uniform light all
-over the centre area, somewhat similar to the arrangement shown in
-<a href="#fig406">Fig. 406</a>.</p>
-
-<p>Roofs over passenger platforms at roadside stations are made in many
-types, the arrangement depending in a great measure upon the width of
-platform to be covered. In many of the earlier stations the roof was
-extended across from side to side, and included the lines of rails as
-well as the <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> platforms, a system which was not only
-costly, but had the
-<!--285.png--><a name="Page_273" id="Page_273"></a><span class="pagenum">[Pg 273]</span>
-disadvantage that the steam and smoke from passing
-trains remained for some time under the roof before it was thoroughly dispersed.
-The more modern and more economical plan is to put the roof or shelter over the
-platforms only, and allow the steam and smoke to pass away into the air. In
-designing the latter class of roof, the fewer supporting columns the better, so
-as to diminish as far as possible the obstructions on the platforms. Where the
-platform is unavoidably narrow, the roof may be carried on curved brackets
-projecting out from the walls.</p>
-
-<p>Except in tropical countries, where shade is more acceptable than strong light,
-a liberal amount of glass should be provided in these platform roofs. On many of
-our home railways they are entirely covered with glass, and the abundance of
-light is found to be of great assistance in the working of the traffic. <a href="#fig411">Figs.
-411</a> to <a href="#fig415">420</a> are sketches of a few out of the many types of small roofs which have
-been erected over single and island platforms.</p>
-
-<p class="p2"><strong>Goods-sheds.</strong>&mdash;The form and dimensions of a goods-shed for any
-station must be determined by the description and amount of traffic to
-be transacted at the particular place. With an estimate of the traffic
-before him, the engineer must consider the internal arrangement of
-building most suitable for the bulk of the merchandise to be
-accommodated. The principal object of the shed is to permit of goods
-being transferred under cover from or to railway trucks or carts
-without being exposed to the weather, and the transfer will be
-expedited if the arrangements are made the most convenient for the
-particular class of merchandise presented.</p>
-
-<p>For some commodities it is considered preferable to unload direct from
-the railway trucks into carts, or <i lang="la">vice versâ</i>, and thus have only one
-handling of the goods. To comply with this method, the cartway must be
-made almost down to the same level as the rails, to allow the carts or
-drays to be drawn close up alongside the railway trucks, as shown in
-<a href="#fig426">Figs. 427 and 428</a>. This type of shed implies a constant supply of
-carts, so as not to detain the railway trucks, or necessitate the
-stacking or storing of goods on the low level floor in the way of
-carting movements.</p>
-
-<div class="figcenter">
- <a name="fig411"></a>
- <img src="images/i274.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 411 through 414 "
- title="Figures 411 through 414"
- />
-</div>
-<div class="figcenter">
- <a name="fig415"></a>
- <img src="images/i275.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 415 through 420"
- title="Figures 415 through 420"
- />
-</div>
-<div class="figcenter">
- <a name="fig421"></a>
- <img src="images/i276.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 421 through 425"
- title="Figures 421 through 425"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig426"></a>
- <img src="images/i277.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 426 through 429"
- title="Figures 426 through 429"
- />
-</div>
-
-<p>For general merchandise in boxes or bales, a raised loading-bank
-inside the shed is usually found to be the most convenient arrangement
-both for loading and unloading. The top of the loading-bank should be
-a little below the level of the railway-truck floor to give clearance
-to all truck-doors opening outwards. By means of short portable
-gangways or landings, the moderate-sized
-<!--286.png-->
-<!--287.png-->
-<!--288.png-->
-<!--289.png-->
-<!--290.png--><a name="Page_278" id="Page_278"></a><span class="pagenum">[Pg 278]</span>
-packages are readily transferred
-to or from the trucks, either by hand or by small two-wheeled
-trolleys, the heavier pieces being lifted by cranes. The cartway
-should run parallel to the rails on the opposite side of the
-loading-bank, and may be either inside or outside the building,
-according to the importance of the place. When the cartway is inside,
-the entire front of the loading-bank is available for cart traffic,
-but this advantage entails a considerable increase in the size and
-cost of the building. When the cartway is outside, the cart traffic is
-worked through large doorways placed at suitable distances, and fitted
-with projecting roofs or awnings to protect the goods during the
-loading or unloading. At some of these doorways, short docks about 10
-feet square, or more, are formed in the loading-bank, into which the
-carts may be set back fairly into the shed for the greater convenience
-of the transhipment of the goods by hand or crane power. Where the
-stacking space is ample, the contents of several railway trucks may be
-discharged on to the loading-bank without any delay in waiting for
-carts, and the same railway trucks may be loaded with other goods and
-dispatched outwards, or may be taken away empty if the loading-bank is
-reserved for arriving goods only. Where the traffic is large and
-constant there is an advantage in having separate goods-sheds for the
-inwards and outwards work.</p>
-
-<p>The following diagram sketches will illustrate some of the many types
-of goods-sheds in use on <span style="white-space:nowrap;">railways:&mdash;</span></p>
-
-<p><a href="#fig421">Fig. 421</a> shows a shed suitable for general merchandise at a small
-roadside station. For economy of construction, the line of rails and
-cartway are both placed outside the building. A small goods-office is
-built at one end, in which is fixed the pedestal and lever indicator
-of the cart-weighing machine. The roof is projected outwards over the
-doorways for the railway trucks and for carts. The railway truck
-doorways are spaced to correspond to the length of the trucks. A
-narrow platform, about 3 feet wide, is formed outside the shed
-alongside the trucks for the convenience of the men when loading or
-unloading.</p>
-
-<p><a href="#fig421">Fig. 422</a> represents a rather larger shed, with the line of rails
-inside the building and cartway outside. With this type the railway
-trucks are entirely under cover, and can be unloaded or loaded more
-conveniently. It has also the additional advantage that the trucks and
-their contents can be left secure when the shed is locked up at
-closing time.</p>
-
-<p><!--291.png--><a name="Page_279" id="Page_279"></a><span class="pagenum">[Pg 279]</span>
-<a href="#fig421">Fig. 423</a> shows a shed with a line of rails down the centre, and a
-loading-bank on each side, the cartways being outside the building;
-one loading-bank is for inwards goods, and the other for outwards
-goods. On the arrival of a loaded railway truck, the door on one side
-is opened, and the contents unloaded on to one of the loading-banks.
-The door is then closed, and the opposite door opened for loading from
-the other loading-bank. By this method a railway truck can be unloaded
-and loaded again without changing its position.</p>
-
-<p><a href="#fig421">Fig. 424</a> represents a shed with two lines of rails down the centre and
-loading-banks on each side, the cartways being outside the building.
-One line of rails and corresponding loading-bank is for inwards goods,
-and the other line of rails and loading-bank for outwards goods. When
-the railway trucks on the arriving line are unloaded, they are either
-drawn out of the shed and shunted on to the opposite line to be loaded
-again, or transferred direct on to the opposite line by turn-tables,
-or traversers, placed at convenient distances between the columns
-supporting the roof.</p>
-
-<p><a href="#fig421">Fig. 425</a> illustrates a shed in which both the line of rails and
-cartway are placed inside the building. This is no doubt the most
-convenient type for transfer of general goods, as all the operations
-of transhipment are carried on entirely under cover; but it is the
-most costly, on account of the large building and roof area required.</p>
-
-<p><a href="#fig426">Fig. 426</a> shows a large double shed similar in general arrangement to
-the type represented in <a href="#fig421">Fig. 425</a>, but with three lines of rails down
-the centre. The line <strong>A</strong> may be used for inwards goods, and <strong>C</strong> for
-outwards. By means of turn-tables, or traversers, connecting the three
-lines at convenient distances in the length of the building, the
-unloaded trucks can be transferred on to the far line, <strong>C</strong>, for
-loading again, or on to the line <strong>B</strong>, to be drawn away out of the
-building. The lines <strong>A</strong> and <strong>C</strong> may both be used for inwards traffic,
-or both for outwards, and the line <strong>B</strong> used for taking away or
-bringing in empty trucks.</p>
-
-<p><a href="#fig426">Fig. 427</a> represents a shed with the line of rails and cartway inside the
-building, and both very nearly on the same level. This class of shed is
-often considered the most suitable for fruit, vegetables, and certain light
-goods which require prompt delivery and careful handling.</p>
-
-<p><a href="#fig426">Fig. 428</a> shows a form of shed with a raised loading-bank on
-<!--292.png--><a name="Page_280" id="Page_280"></a><span class="pagenum">[Pg 280]</span>
-one side
-of a line of rails, and a cartway on the other. With this arrangement
-the railway trucks may be loaded or unloaded, either from the raised
-loading-bank or direct from carts and drays drawn up alongside the
-trucks, according to the description of merchandise presented.</p>
-
-<p><a href="#fig426">Fig. 429</a> shows a type of umbrella roof sometimes erected over a narrow
-loading-bank outside of a goods-shed. It is simple and economical in
-construction, and provides good accommodation for loading and
-unloading under cover packages and goods of secondary importance.</p>
-
-<p>The above sketches illustrate some of the many arrangements for
-goods-sheds, and can be modified and extended in several ways. The
-leading dimensions, widths of loading-banks, cartways, and gauge of
-lines, will have to be adjusted to suit circumstances.</p>
-
-<p>Looking at a goods-shed merely as a medium for the convenient transfer
-of merchandise between the railway and the roadway, the inference is
-soon drawn that the removal of the goods into trucks or carts should
-be effected as speedily as possible, otherwise a large extent of
-shed-room will be required for carrying on a moderate amount of work.
-Every effort should be made to clear the goods from the loading-bank
-as soon as they have been properly unloaded and checked. Any laxity in
-this respect will cause an outcry for increased accommodation, which a
-little more energy and careful organization would have prevented.</p>
-
-<p>Timber plank floors are generally preferred for inside loading-banks.
-Inside cartways should be formed either of granite setts or
-wooden-block paving; the latter is better, being less noisy, and, if
-occasionally sprinkled with sand, will afford a good foothold for the
-horses. A macadamized roadway under cover is never satisfactory, as it
-is always dry, and never binds together into a compact even surface.
-Sliding or rolling doors are the best for goods-sheds, as they are
-more out of the way, and under better control during high winds.</p>
-
-<p>Cranes of appropriate strengths, and worked by hand or other
-motive-power, should be distributed in suitable positions throughout
-the shed. They should be placed so that they can, when required, lift
-direct out of a railway truck on the one side, and deposit into a cart
-or dray on the opposite side of the loading-bank.</p>
-
-<p><!--293.png--><a name="Page_281" id="Page_281"></a><span class="pagenum">[Pg 281]</span>
-Goods-sheds may be built of stone, brick, iron, or timber, or a
-combination of all of them. Where the requirements are well proved,
-and the traffic certain, it is better to build a substantial permanent
-structure. Iron sheds, with sides and roofs of galvanized corrugated
-iron sheets, will last for many years if not made of too light
-materials. There are many cases where it is more prudent to put up a
-goods-shed in timber than to incur the cost of one of more permanent
-character. Where the traffic is uncertain, or the foundations bad, or
-out in undeveloped districts abroad, a building of timber will serve
-the purpose for a number of years, or until the period of probation
-has passed, and the actual requirements are accurately ascertained. In
-a timber-built shed, the decay usually commences about the ground
-line, but if the nature of the soil will permit of the construction of
-a small dwarf foundation wall of masonry or concrete up to about nine
-inches above the ground line, the life of the building will be
-prolonged for several years.</p>
-
-<p>The best method of admitting daylight into a goods-shed is from the
-roof, and a liberal extent of roof-glazing should be provided for the
-full length of the building, and so distributed as to be well over the
-loading-banks. In tropical countries the amount of roof light must be
-reduced, on account of the great glare from the sunlight.</p>
-
-<p>An ample supply of artificial light will be necessary when working
-after dark or during the night. In some instances the goods-sheds in
-large and important business centres have one or more upper storys, in
-which goods are warehoused pending the owners’ instructions, the goods
-being transferred between the loading-banks and upper floors by lifts
-or cranes.</p>
-
-<p>A proper supply of weighing machines for carts, drays, railway trucks,
-and packages on the loading-banks will be necessary to facilitate the
-checking of the goods.</p>
-
-<p>There is always a large proportion of traffic which can be dealt with
-outside the goods-sheds, either on loading-banks or cartways alongside
-the sidings. Outside loading-banks should be of good width, with
-approach roads of easy gradient. In tropical countries a light shed,
-open on all sides, is frequently erected over a portion of these
-outside banks, to protect the goods and workmen from the heat of the
-sun. Fixed cranes or travelling cranes will be required for lifting
-the large packages, heavy castings, and logs of timber. Where there is
-a large cattle traffic,
-<!--294.png--><a name="Page_282" id="Page_282"></a><span class="pagenum">[Pg 282]</span>
-separate sidings, loading-banks, and approach
-roads should be set apart for the purpose, with suitable water-troughs
-and cleansing appliances. Horses can be unloaded at any loading-bank,
-but for the more valuable class of animals and for carriages it is
-usual to construct a special horse and carriage dock, as shown in <a href="#fig430">Fig.
-430</a>, the carriages being wheeled off the end of the carriage truck, as
-indicated in the section. Cartways alongside the sidings are very
-convenient for unloading coals, stone, bricks, sand, lime, and many
-other materials which have to be passed out of the trucks in small
-quantities at a time. To encourage and facilitate traffic at roadside
-stations, traders are frequently allowed to stack or store large
-supplies of some of the above materials on ground set apart for the
-purpose near some convenient siding, the stock being disposed of in
-detail to suit the local requirements. Coal-drops are sometimes
-adopted where there is a large trade in that commodity. They are
-constructed by carrying the line of rails on strong balks of timber or
-small girders placed across the top of walled-in coal-yards or divided
-areas. The coal is thrown out of the trucks, and falls a depth of 15
-or 20 feet into the yard below. In consequence of the height from
-rail-level to ground a large tonnage can be piled up, and stored in a
-small area, and the unloading of the trucks effected very rapidly,
-particularly so where special trucks with opening floors or hinged
-bottoms are used for the purpose. In many cases capacious roofed-in
-sheds are built for storing coals, lime, cement, grain, or other
-materials liable to deterioration from the weather. These sheds are
-built alongside a siding; the contents of the trucks are unloaded or
-thrown into the sheds through doors spaced to correspond to the
-railway-truck doors, and are carted away through doorways on the
-opposite side.</p>
-
-<p>It is customary to place <em>buffer-stops</em> of some form at the
-termination of dead-end sidings in a station, to bring to a stand such
-carriages or waggons as may be approaching with too much speed to be
-stopped without the interposition of some substantial barrier.</p>
-
-<p><a href="#fig430">Figs. 430, 431, 432, and 433</a> are sketches of some of the many kinds of
-buffer-stops, and will explain themselves. In <a href="#fig430">Fig. 430</a> the buffer-stop
-is made of flange rails, and is shown as fitted in a carriage-dock
-with wrought-iron plate landing, <strong>A</strong>, and plate-iron hinged flaps,
-<strong>B</strong>, <strong>B</strong>. The latter are turned over, and rest on the floor of the
-carriage-truck, to form a pathway when taking on or off a vehicle.</p>
-
-<div class="figcenter">
-<!--295.png--><a name="Page_283" id="Page_283"></a><span class="pagenum">[Pg 283]</span>
- <a name="fig430"></a>
- <img src="images/i283.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 430 through 433"
- title="Figures 430 through 433"
- />
-</div>
-
-<p><!--296.png--><a name="Page_284" id="Page_284"></a><span class="pagenum">[Pg 284]</span>
-<a href="#fig430">Fig. 431</a> shows a buffer-stop made of double-head or bull-head rails;
-and <a href="#fig430">Fig. 432</a> is a buffer-stop made of heavy timbers.</p>
-
-<p><a href="#fig430">Fig. 433</a> shows a very simple buffer-stop frequently adopted for
-sidings where there is not much traffic. It is made of good old
-sleepers bound together with old double-head rails, and the interior
-filled with earth or clay.</p>
-
-<p>In addition to the buildings alluded to in the foregoing description,
-the engineer has to design and construct very many others in
-connection with railways. These will include large running-sheds for
-stabling working locomotives; sheds for housing carriages; workshops
-for building and repairing engines, carriages, and waggons; foundries;
-large stores for materials; offices; dwelling-houses; mess-rooms,
-etc.; many of them involving questions of difficult foundations, and
-nearly all of them requiring special strength and stability to meet
-the heavy weights and vibrations to which they are subjected.</p>
-</div><!--end chapter four-->
-
-<div class="chapter">
-<!--297.png--><a name="Page_285" id="Page_285"></a><span class="pagenum">[Pg 285]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER V.</h3>
-
-<p class="center smaller">Sorting-sidings&mdash;Turn-tables&mdash;Traversers&mdash;Water-Tanks and Water-Columns.</p>
-
-<p class="p2"><strong>Sorting-sidings.</strong>&mdash;On many important long main lines it is necessary
-to establish special independent sidings for sorting or arranging
-waggons of merchandise and minerals. Where there are only two lines of
-rails to serve for the <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> service of a heavy
-passenger and goods traffic, it is imperative to restrict those lines
-as much as possible to the actual transit of trains, and not to block
-them by unnecessary occupation for shunting purposes. A goods train
-running a long distance collects waggons from many roadside stations,
-and at some of them several waggons will be taken on, to be forwarded
-to various and widely distant destinations. The accumulated train
-comprises waggons which must be divided out into groups, to be passed
-on either to distant sections of the same railway system, or on to
-neighbouring lines. To avoid interruption to the train-working, and
-the delay of complicated shunting operations at the roadside stations,
-the waggons are attached just as they are dicked up, and the work of
-sorting is allowed to stand over until the train arrives at the place
-assigned for the purpose. A site for sorting-sidings is generally
-selected where the ground and gradient are favourable, and where ample
-room can be obtained for a large number of short parallel lines, with
-space for future extensions. The arrangement that naturally suggests
-itself is that of a series of fan-shaped sidings leading out of main
-shunting lines, separate from the main-traffic lines. In some cases
-the sorting-sidings are laid down with dead-ends, as in <a href="#fig434">Fig. 434</a>, and
-in others they are made as through sidings, connecting at both ends
-with shunting lines and main-traffic lines, as in <a href="#fig434">Fig. 435</a>. Each of
-the sidings is usually made sufficiently long to hold a complete train
-of sorted waggons, and the number of
-<!--298.png--><!--299.png--><a name="Page_287" id="Page_287"></a><span class="pagenum">[Pg 287]</span>
-them will depend upon the number
-of sections to be served, and the amount of waggons to be sorted.
-Sometimes the sidings are laid with a slight falling gradient leading
-away from the main shunting lines, to facilitate the running out of
-the waggons into the respective sidings.</p>
-
-<div class="figcenter">
- <a name="fig434"></a>
- <img src="images/i286.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 434 and 435"
- title="Figures 434 and 435 "
- />
-</div>
-
-<p>An arriving goods train is first drawn out of the main-traffic lines
-into one of the shunting lines, and then handed over to the staff of
-men in charge of the sorting operations, who at once mark the waggons
-according to the number or designation of the particular siding into
-which they have to be placed. A suitable engine is generally set apart
-for this work, and in a very short time the entire train is divided
-out by one or more waggons at a time, and distributed into the various
-sidings, representing different sections of the line, or groups to be
-handed over to neighbouring railways. When one of these
-sorting-sidings contains a full complement of waggons, an engine is
-attached, and the train despatched to its destination, leaving the
-siding clear for another set of waggons. Where the trains to be sorted
-are very numerous, two or more shunting-engines may be engaged working
-at the same time on distinct sets of shunting lines and sidings.
-Sometimes it may be expedient to have one lot of sorting-sidings
-leading off the <span class="muchsmaller">UP</span> line, and another lot leading off the
-<span class="muchsmaller">DOWN</span> line, to meet the requirements of trains coming and
-going in both directions. With sidings well laid out, and fitted with
-ample facilities, a well-organized staff can carry out a very large
-amount of work both expeditiously and economically. There are several
-of these sorting-sidings stations in operation, where from one
-thousand to two thousand waggons are sorted and marshalled into trains
-every twenty-four hours.</p>
-
-<p>The above diagram sketches merely illustrate the general principle of
-the sorting-sidings, and may be modified and enlarged in many ways to
-suit the traffic requirements and local surroundings.</p>
-
-<p class="p2"><strong>Turn-tables.</strong>&mdash;Turn-tables revolving on fixed centres are made of
-various sizes according to their use for engines, carriages, or
-waggons. The carrying-beams may be made of cast-iron, wrought-iron, or
-steel, but the latter material is the most suitable for tables of more
-than 20 feet diameter. For small turn-tables, cast-iron beams will
-serve very well, for although more liable to fracture, they will not
-suffer so much from rust and oxidization as wrought-iron or steel.</p>
-
-<div class="figcenter">
-<!--300.png--><a name="Page_288" id="Page_288"></a><span class="pagenum">[Pg 288]</span>
- <a name="fig436"></a>
- <img src="images/i288.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 436 through 440"
- title="Figures 436 through 440"
- />
-</div>
-
-<p><!--301.png--><a name="Page_289" id="Page_289"></a><span class="pagenum">[Pg 289]</span>
-Opinions as to the most convenient position and use of turn-tables
-have undergone a considerable modification during the past twenty or
-twenty-five years. Circular and semi-circular running-sheds for
-engines, as in <a href="#fig436">Figs. 436 and 437</a>, are not so often adopted now as
-formerly. Although compact and accessible in theory, they possess the
-one great drawback that when the turn-table in the centre becomes
-deranged by wear or accident, none of the engines on the
-standing-lines inside the building can be taken out until the
-turn-table is again put into working order. A stock of from twenty to
-thirty engines might thus be put entirely out of the service for a day
-or more. This objection is considered to be of so serious a nature
-that running-sheds are now almost always constructed of rectangular
-form, of which <a href="#fig436">Fig. 438</a> is a type.</p>
-
-<p>With this description of shed, the lines of rails are laid down
-parallel to one another, and the engine turn-table is placed on a line
-separate and distinct from those lines forming connections with the
-shed.</p>
-
-<p>Where there is a large goods traffic, an endeavour is generally made
-to so lay down the goods-sheds and approach lines and sidings, that
-the full complement of waggons may be shunted in or out of the shed at
-one operation. This arrangement, which dispenses with turn-tables
-altogether, admits of the ready removal of a central or far-end
-waggon, without the necessity of taking out so many others in front
-one by one over the turn-table. At the same time, there are large
-numbers of these waggon turn-tables in use, and there are many cases
-where access to side sheds or detached stores can only be obtained by
-turn-tables.</p>
-
-<p>A goods-shed and lines laid down with turn-tables, as in <a href="#fig436">Fig. 439</a>,
-will always be more tedious and costly to work than one laid down with
-direct through lines, as in <a href="#fig436">Fig. 440</a>. Should either of the turn-tables
-shown on <a href="#fig436">Fig. 439</a> get out of order and become incapable of turning,
-then the entire side of the shed controlled by that table will be
-rendered useless until the defect be remedied.</p>
-
-<p>Engine turn-tables are rarely made with more than one road on the top.
-The most modern types generally consist of two strong wrought-iron or
-steel-plate girders well braced together and securely attached to a
-middle framework which rests on and revolves round a centre-piece
-fixed on a solid foundation
-<!--302.png--><a name="Page_290" id="Page_290"></a><span class="pagenum">[Pg 290]</span>
-To the ends of the girders are attached
-large roller wheels which travel round a solid iron or steel
-roller-path laid down along the circumference. These modern
-turn-tables are generally worked on the balancing principle, by
-bringing the engine and tender to a stand in such a position on the
-rails that the greater portion of the weight is thrown on to the
-cup-shaped steel centre, so that a small force applied to the long
-outrigged hand-levers at the ends is sufficient to turn one of the
-heaviest locomotives. <a href="#fig441">Figs. 441 and 442</a> give sketch plan and section
-of one of these steel-plate girder turn-tables, which has few parts,
-and very little to get out of order. The end rollers guide the table
-when making any portion of a revolution, and carry such part of the
-weight as may not be taken up by the centre. A recess is shown in side
-wall to facilitate the inspection of end rollers. In the earlier forms
-of engine turn-tables, the revolving movement was effected by
-attaching to the upper portion of the girders a strong winch, which
-acted upon gearing fixed either to the end rollers, or direct on to a
-toothed ring forming part of the roller-path. In cases where the
-engine turn-table was in constant use, as in connection with a large
-running-shed, the winch was sometimes driven by a small steam-engine
-to expedite the movement.</p>
-
-<p>The great increase in the lengths and weights of modern locomotives
-has necessitated the removal of many of the old small turn-tables, and
-replacing them with others of 45 or 50 feet, or more, in diameter.</p>
-
-<div class="figcenter">
- <a name="fig441"></a>
- <img src="images/i291.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 441 through 445"
- title="Figures 441 through 445"
- />
-</div>
-
-<p>An engine turn-table is a costly item in railway requirements, not
-only in the girder-work, but in the large amount of building in the
-side walls and centre pier, and an effort is always made to avoid the
-outlay unless the table can be placed where it may be of permanent
-use. In the construction of foreign railways, and in our colonies,
-where the lines are opened in sections as the work goes forward, the
-temporary arrangement shown in <a href="#fig441">Fig. 443</a> is frequently used instead of
-an engine turn-table. The sketch will almost explain itself. On the
-main line, <strong>A</strong>, <strong>B</strong>, <strong>C</strong>, <strong>D</strong>, switches are placed at <strong>B</strong> and <strong>C</strong>,
-from which turn out curved lines, uniting at the switches <strong>E</strong>. An
-engine proceeding from <strong>A</strong>, and passing round the curve <strong>B</strong>, <strong>E</strong>, <strong>G</strong>,
-then round curve <strong>G</strong>, <strong>E</strong>, <strong>C</strong>, and back along main line, <strong>D</strong>, <strong>C</strong>,
-<strong>B</strong>, <strong>A</strong>, will be turned round as efficiently as on a turn-table. The
-writer has used this arrangement abroad with great advantage. It
-involves very little work or expense beyond laying down the permanent
-way, and so soon as the
-<!--303.png--><!--304.png--><a name="Page_292" id="Page_292"></a><span class="pagenum">[Pg 292]</span>
-temporary terminus of the line has been advanced
-further ahead, the rails and sleepers can be lifted and used again
-elsewhere.</p>
-
-<p><a href="#fig441">Figs. 444 and 445</a> give sketch plan and section of a waggon turn-table
-which has been largely adopted. The centre should be securely fixed on
-a solid foundation of masonry, brickwork, or concrete. The deep outer
-cast-iron ring is made in segments, properly fitted and bolted
-together, and fastened down to the foundation course. The stop-checks
-are cast on to this outer ring. Two roads, at right angles to each
-other, are laid on the turn-table, so that waggons to or from the
-goods-shed have only to make one quarter turn of the table. The top is
-generally covered with either chequered iron plates or timber to give
-good foothold for the men and horses which have to pass over in moving
-the waggons. If properly balanced, the table is easily turned by men
-pushing at the opposite corners of the waggon, or by a horse and
-tail-rope, or by hydraulic power through a capstan. In many cases of
-bad or soft foundations these small turn-tables are erected on a
-strong framework of creosoted timber.</p>
-
-<p>Carriage turn-tables are now very rarely used. With the old short
-four-wheeled carriages the moderate-size turn-table was convenient for
-transferring an extra carriage to or from a spare carriage-line
-alongside the making-up train at a platform, but modern carriages are
-now so much longer, some of them twice the length, or more, than
-formerly, that nothing less than an engine turn-table would be large
-enough for them. Sometimes a carriage traverser is used for this
-station work, but much more frequently these long carriages are
-shunted on or off the making-up train by simply running them in or out
-through the nearest switches and cross-over road.</p>
-
-
-<div class="figcenter">
- <a name="fig446"></a>
- <img src="images/i293.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 446 and 447"
- title="Figures 446 and 447"
- />
-</div>
-
-<p><a href="#fig446">Fig. 446</a> is a sketch of a carriage-traverser, of length to suit an
-ordinary six-wheeled carriage. The length, however, may be extended to
-take on a bogie carriage or any other long carriage. The framing is
-made of wrought-iron or steel, well braced together. The carrying
-wheels, <strong>W</strong>, <strong>W</strong>, run upon rails laid at right angles to the
-running-line or siding, and the carriage is moved on to or off the
-traverser by means of the hinged ramps shown at <strong>R</strong>, <strong>R</strong>. A carriage,
-once on the traverser, may be moved across one or several lines of
-running road, according to the extent of traverser line laid down; and
-this appliance is very suitable for large terminal stations and
-carriage-repair shops. It
-<!--305.png--><!--306.png--><a name="Page_294" id="Page_294"></a><span class="pagenum">[Pg 294]</span>
-will be observed that the operations of the
-turn-table and the traverser are quite distinct. With the former a
-vehicle can be transferred from one line to another, and also turned
-completely round; but with the traverser the vehicles are simply moved
-in a parallel direction, from one line to another, and when it is
-necessary to turn or change a vehicle end for end, as in the case of a
-mail-bag-catching apparatus van or a special saloon, then resort must
-be had to a turn-table.</p>
-
-<p class="p2"><strong>Cranes.</strong>&mdash;A large portion of the merchandise conveyed on railways
-must be lifted into or out of the trucks by cranes. The position,
-description, and capacity of these will depend upon the materials to
-be handled. Large slow-working powerful cranes will be necessary for
-raising heavy castings, large logs of timber, or massive blocks of
-stone; while the small quick-acting cranes will be more suitable for
-dealing with the lighter packages, casks, and bales.</p>
-
-<p><a href="#fig446">Fig. 44</a>7 shows a gantry or overhead crane, used for lifting heavy
-weights out of an ordinary road-waggon, carrying them a short
-distance, and then depositing them in a railway truck, or <i lang="la">vice
-versâ</i>. Double-flanged rollers, attached to the ends of the platform
-<strong>C</strong>, <strong>C</strong>, run upon the rails <strong>R</strong>, <strong>R</strong>, which are fixed on
-the top of the beams <strong>B</strong>, <strong>B</strong>, secured to the verticals <strong>A</strong>, <strong>A</strong>.
-The working length of the gantry is only limited by the number of the
-verticals, and this, being the fixed portion of the work, may be
-extended out to any distance required. The travelling or carrying
-girders of the platform <strong>C</strong>, <strong>C</strong> may be made of wrought-iron, steel,
-or timber. They must be strongly framed and braced together as a
-platform to carry the lifting machinery and weight lifted, and have
-convenient gearing for effecting the transverse or side-to-side
-movement, as well as a horizontal movement along the line of rails on
-top of the verticals. Where the fixed portion of the gantry is of
-considerable length, two or more travelling platforms can be used. In
-the sketch given above, the entire gantry is shown as made of timber,
-but iron or steel can be equally well adopted, and continuous masonry
-or brickwork walls may be built to serve as verticals.</p>
-
-
-<div class="figcenter">
- <a name="fig448"></a>
- <img src="images/i295.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 448 through 450"
- title="Figures 448 through 450"
- />
-</div>
-
-<p><a href="#fig448">Fig. 448</a> is a sketch of a small handy crane for warehouse work; it is
-quick in action, and restricted to weights not exceeding twelve
-hundredweight. This form of crane may be strengthened to lift still
-greater loads, but in doing so the additional size of the parts, and
-the corresponding extra labour
-<!--307.png--><!--308.png--><a name="Page_296" id="Page_296"></a><span class="pagenum">[Pg 296]</span>
-in working, detract from its efficiency
-as a quick-acting crane for light weights.</p>
-
-<p><a href="#fig448">Fig. 449</a> shows an ordinary fixed three-ton jib crane, a very
-convenient size for general station work. The centre pillar is fixed
-into a bed of masonry or a solid block of concrete. The jib is of
-wrought-iron or steel, those materials being so much more reliable
-than timber, and very little more expensive. This crane must be fixed
-so that in one direction the jib may command the centre of a railway
-truck, while in the other it can conveniently raise the packages to or
-from the carts or loading-bank alongside. In the sketch the crane is
-shown as placed on the loading-bank, but it may be placed on the same
-level as the rails if preferred. Cranes of this type and strength are
-frequently found necessary for the inside work of goods-sheds, where
-packages of considerable weight have to be handled. A very similar
-class of jib-crane is constantly made for lifting weights of five or
-ten tons or more, the different parts being made stronger and heavier
-to correspond to the weights to be raised.</p>
-
-<p><a href="#fig448">Fig. 450</a> shows a five-ton travelling crane. Although more costly, it
-has the advantage over a fixed crane that it can be moved about from
-place to place. It is mounted on a very strong waggon framework, and
-provided with springs and spring buffers. Instead of moving round a
-long deep centre, the jib of the travelling-crane is arranged to work
-round a bevelled metal roller-path laid down on the platform of the
-waggon, and has a heavy counterweight loaded to correspond to its
-capacity. Before commencing to lift any weight strong oak blocks or
-filling pieces are inserted between the tops of the axle-boxes and the
-under side of main beams of waggon, to relieve the springs of the
-pressure which would arise from the weight lifted. From the four
-corners of the waggon are suspended chains carrying gripping-hooks to
-be attached or clipped round the rails. These gripping-hooks, when
-firmly secured to the rails, prevent the crane from tilting over, as
-the weight of the waggon and also of the rails and sleepers are
-brought into play to counteract any tendency to throw the crane off
-its proper balance. With the larger size travelling cranes, capable of
-lifting ten or fifteen tons or more, outriggers of joist or
-<strong>I</strong>-iron, moving in slides, are run out at right angles on either
-side, and can be loaded with bars of iron or other weights to form a
-counterpoise.</p>
-
-<p><!--309.png--><a name="Page_297" id="Page_297"></a><span class="pagenum">[Pg 297]</span>
-A medium-sized travelling-crane is a most useful appliance about a
-railway station; it has a much greater range of utility than a fixed
-crane, but it is not always appreciated as it should be. It merely
-requires a line of rails laid down parallel to the rails of siding,
-and may be placed either on the same level as the siding, or on the
-level of the loading-bank. Being laid flush with the roadway, the
-rails do not present any obstacle to the passage of carts or movement
-of merchandise. As one waggon on the siding is loaded or unloaded, the
-crane can be moved along its own line of rails, and be put to work at
-another without the necessity of moving or drawing out any of the
-railway waggons on the siding. Five, ten, or twenty, or more railway
-waggons can be dealt with in this way, according to the length of
-crane-line laid down. The crane can also be readily removed to another
-part of the station-yard, or to another station along the line. For
-stations with an intermittent or spasmodic traffic in heavy timber,
-large blocks of stone, or other unwieldy articles, a travelling-crane
-is particularly suitable, as it will meet all the wants so far as the
-lifting is concerned, and when the rush of traffic is over, it can be
-easily transferred to some other sphere of usefulness. The
-crane-siding itself is never very costly, as the rails are generally
-old rails taken out of the main line, and laid on good second-hand
-sleepers. They have little to do, and merely form a track for the
-moving crane.</p>
-
-<p><a href="#fig451">Fig. 451</a> is a sketch of an ordinary Goliath crane constructed of
-timber. The general arrangement and capabilities of this crane are
-somewhat similar to those of the gantry shown in <a href="#fig446">Fig. 447</a>. Both of
-them are designed to lift heavy weights, and move them sideways into,
-or out of, ordinary road waggons, but the methods of application are
-different. In the gantry the verticals are permanently fixed, whereas
-in the Goliath the verticals and overhead girders are all attached and
-braced together, forming a complete framework which is carried by
-double flanged rollers running on the lines of rails <strong>R</strong>, <strong>R</strong>. The
-winches or gearing for lifting the weights, or slinging them sideways,
-or for propelling the crane forward on the rails, are attached to the
-verticals as shown, and are worked from the ground-level instead of
-the overhead platform, as indicated in the gantry. As each Goliath
-crane is complete in itself, there is nothing to prevent two or three
-of them working at the same time on a long length of crane-line.</p>
-
-<div class="figcenter">
-<!--310.png--><a name="Page_298" id="Page_298"></a><span class="pagenum">[Pg 298]</span>
- <a name="fig451"></a>
- <img src="images/i298.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 451 and 452"
- title="Figures 451 and 452"
- />
-</div>
-
-<p><!--311.png--><a name="Page_299" id="Page_299"></a><span class="pagenum">[Pg 299]</span>
-<a href="#fig451">Fig. 452</a> shows an ordinary derrick crane, which, on account of the
-large and varying sweep of the jib, is found very convenient for
-certain classes of work. It occupies a considerable amount of room,
-and its adoption is therefore limited to situations where space is of
-secondary importance.</p>
-
-<p>All the cranes described above are shown as worked by hand-power, but
-they may be worked by steam, hydraulic machinery, or electricity.
-Manual power will be the most economical where the use of a crane is
-only occasional, but it would be too slow and costly where there is
-constant heavy work.</p>
-
-<p class="p2"><strong>Water-tanks.</strong>&mdash;A supply of good water forms an important item in
-railway working, and ample provision must be made at all principal
-stations for the requirements of engines and general station purposes.
-According to the locality, the water may either be procured from the
-main of some established waterworks company, or be pumped from a well,
-or forced up from a stream by a ram, or brought down by gravitation in
-pipes from a spring or stream at a distance. Water thus obtained is
-conducted into tanks placed at a height of 18 or 20 feet, or more,
-above the level of the rails, and forms a storage supply from which
-deliveries can be made at a fair pressure and in large volume. The
-tanks may be made of cast-iron, wrought-iron, or steel, or even of
-wood. In the great timber-producing countries abroad, water-tanks,
-some of them of large capacity, are very frequently made of wood, the
-circular or half-cask form being preferred; but at home, and on
-European lines generally, wooden tanks are rarely used except for
-temporary purposes. Cast-iron being less liable to deterioration from
-rust than wrought-iron or steel, is much used for water-tanks.</p>
-
-
-<div class="figcenter">
- <a name="fig453"></a>
- <img src="images/i300.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 453 through 464"
- title="Figures 453 through 464"
- />
-</div>
-
-<p><a href="#fig453">Figs. 453 to 457</a> are sketches of a medium-sized cast-iron water-tank,
-to hold about 7800 gallons. The size may be varied both in length,
-width, and depth, without in any great measure altering the type. The
-lower portion, or tank-house, may be of stone, brick, wood, or iron
-framework, and may be utilized as a pump-room, store, or lamp-room. In
-the sketch given a row of cast-iron girders are placed across the top
-of the walls of the tank-house, to carry the tank, the plate-joints of
-the latter being made to coincide with the centre lines of the
-girders. The lower and upper edges of the tank-plates are shown curved
-in section, the former for appearance and facility of cleaning, and
-the latter to check the tendency of the water rippling or
-<!--312.png--><!--313.png--><a name="Page_301" id="Page_301"></a><span class="pagenum">[Pg 301]</span>
-splashing
-over the sides when disturbed during high winds. The large pipe, <strong>A</strong>,
-is securely bolted at the bottom of the tank, and forms a shield or
-funnel through which the supply pipe, <strong>B</strong>, passes upwards into the
-tank. <strong>C</strong> is an overflow, or waste pipe, to carry away any surplus
-which may find its way into the tank after the water has risen to its
-fixed maximum height. All the contact surfaces of the cast-iron
-tank-plates must be accurately chipped or planed, and fitted to ensure
-water-tight joints. Stay-rods must be placed at frequent intervals,
-connecting the vertical or outer plates to the horizontal or floor
-plates. When required to hold more than 20,000 gallons, it is better
-to make the tank in two parts, by placing a permanent plate <a
-name="partition"></a>partition
-across the middle, in reality making two separate tanks, which can be
-connected or disconnected at will. The double tank arrangement gives
-additional strength, and possesses the advantage that the one tank can
-be emptied and cleaned out while the other remains in service.</p>
-
-<p>Water-tanks constructed of wrought-iron or steel plates are usually
-made circular in form, with vertical sides. The floor-plates must be
-either carried on small girders, as in the cast-iron tank, or be
-strengthened internally with angle-irons, tee-irons, and tie-rods. The
-rivetting must be well done, all joints sound and watertight. This
-class of tank must be kept well painted, or oxidization will take
-place very rapidly. The arrangement of inlet, waste-pipe, and delivery
-pipe may be the same as for the cast-iron tank. Although frequently
-seen abroad, these circular wrought-iron tanks are not often adopted
-at home. By many the appearance of the circular tank is considered
-inferior to one of neat rectangular shape, and the form of the round
-tower does not lend itself so conveniently for use as a pump-room or
-store.</p>
-
-<p>There may be no practical difficulty in constructing a large circular
-wooden vat or water-tank, but there cannot be any great actual
-economy, except in those countries where suitable timber is very
-cheap, and iron very dear. The wooden tank must be made of selected
-materials, and by skilled workmen; but however carefully constructed
-it cannot be expected to last so long as an iron tank. In many parts
-of the United States of America there are excellent examples of the
-circular wooden tank, strongly put together, and covered with a light
-ornamental roof. Numbers of these wooden tanks have been erected there
-in places where the cost of carriage alone of an iron tank would
-<!--314.png--><a name="Page_302" id="Page_302"></a><span class="pagenum">[Pg 302]</span>
-have been a serious item, and where suitable timber was fortunately
-close at hand.</p>
-
-<p>In cases where engines are watered direct from a water-tank, a simple
-delivery-valve, as shown in the sketch (Fig. 458), will answer the
-purpose. This valve has to be pulled open by the chain and lever,
-<strong>D</strong>, and when released falls with its own weight, and is kept <a
-name="closed"></a>closed
-by the pressure of the water above. The delivery-pipe should not be
-less than 7 or 8 inches in diameter, to accelerate the filling of the
-tenders. Where water has to be delivered to engines at two or more
-places in a station-yard, and the supply derived from the same
-principal tank, the result may be obtained either by laying down 7 or
-8-inch main pipes from the principal tank to separate water-columns,
-or by erecting two or more pedestal water-tanks, similar to Figs. 459
-to 462, each of which holds a little more than the average quantity
-for one tender, and can be fed from the principal tank by a
-comparatively small pipe of 3 or 4 inches in diameter. It is simply a
-question of expense&mdash;whether it is cheaper to lay down a long length
-of 7 or 8-inch main pipe and ordinary water-columns, or to adopt the
-small pipes and pedestal tanks.</p>
-
-<p><a href="#fig453">Figs. 459 to 462</a> are sketches of a medium-sized pedestal water-tank to
-hold 1200 gallons. The supporting column must have a very wide base,
-bolted down to a solid foundation. The tank itself, made circular in
-plan, is generally constructed of light plates of wrought-iron or
-steel, the lower portion or floor of tank being very securely attached
-to the vertical column. Notwithstanding their top-heavy appearance,
-these pedestal tanks can be made very firm and steady if enough width
-be given to the base-plate, and the tank properly fixed to the column.
-Water is led into these pedestal tanks by a small pipe passing up
-inside the supporting column, and the delivery may be effected by a
-simple valve, as explained for <a href="#fig453">Fig. 458</a>.</p>
-
-<p>Fig 463 shows one type of water column for watering engines. The wide
-base-plate is bolted down on to a foundation of stonework, brickwork,
-or concrete, and the main supply pipe (not less than 7 or 8 inches in
-diameter) is carried up inside the column, and connected with the
-screw valve, <strong>A</strong>, which regulates the delivery to the tenders. The
-curved top, which forms the outlet, and carries a leather hose, works
-on a swivel joint, and can be swung round, either to the right or
-left, for convenience of supplying engines on one or two
-standing-lines. The delivery
-<!--315.png--><a name="Page_303" id="Page_303"></a><span class="pagenum">[Pg 303]</span>
-valve can be opened or closed by the
-small hand-wheel <strong>B</strong>, which is conveniently accessible to the man on
-the tender. On the above sketch (Fig. 463) the water column is shown
-placed at an ordinary normal distance from the rails; but in cases
-where there is considerable space between the two lines of rails, or
-where a platform intervenes, the swinging arm may be extended out to
-the necessary length, and counterbalanced as shown in <a href="#fig453">Fig. 464</a>.</p>
-</div><!--end chapter five-->
-<div class="chapter">
-
-<!--316.png--><a name="Page_304" id="Page_304"></a><span class="pagenum">[Pg 304]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER VI.</h3>
-
-<p class="center smaller">Comparative Weights of some Types of Modern Locomotives.</p>
-
-<p class="p2"><strong>Weights of Locomotive Engines.</strong>&mdash;The demand for higher speeds of
-passenger trains, with more conveniences, luxuries, and consequent
-increased weights in the carriages, has naturally led to greatly
-increased power and weight of the locomotives devoted to the passenger
-service. Although these engine weights have so largely increased
-during the past twenty-five years, there is nothing to indicate that
-they have yet reached the maximum. The tendency is still to increase,
-and will doubtless continue, so long as the permanent way can be made
-to sustain such enormous rolling loads. Locomotives for goods trains
-have also increased in power and size, but perhaps not in the same
-proportion as those for the passenger service. There is not the same
-disposition to expedite the transit of goods and minerals, which do
-not deteriorate during a long journey. Perishable articles, such as
-fish, fruit, and milk, are usually conveyed by passenger trains, or
-trains set apart specially for the purpose.</p>
-
-<div class="figcenter">
- <a name="fig465"></a>
- <img src="images/i305.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 465 through 467"
- title="Figure 465 - 467"
- />
-</div>
-
-<p>The heavier engine doubtless possesses greater tractive power, but
-apart from the question of tractive power is the all-important one of
-steadiness and safety on the rails. A locomotive passing round a
-curve, even at a moderate velocity, produces disturbances in
-proportion to the capability of the machine to adapt itself to the
-altered position, and if both the engine and permanent way are
-constructed so as to be almost unyielding, then destructive wear and
-tear and increased risk of derailment must ensue. The adoption of the
-four-wheel bogie truck to the locomotives on our home and continental
-lines&mdash;although very slow in coming&mdash;has contributed greatly to their
-improvement, enabling the weight to be distributed over a longer, yet
-more flexible wheel-base, affording greater facility and comparative
-safety in traversing curves; and rolling, or
-<!--317.png--><!--318.png--><a name="Page_306" id="Page_306"></a><span class="pagenum">[Pg 306]</span>
-passing over the rails,
-with as little injurious effect to them as possible. It is strange to
-find that the four-wheel bogie truck, originally designed in England
-in the early days of the railway era, should for so long have met with
-so little favour on this side of the Atlantic. The Americans, at all
-times prompt to recognize any appropriate mechanical arrangement,
-adopted the bogie truck upon its first introduction into the States.
-They have worked out many improvements in the details, and upon the
-thousands of locomotives on their vast network of railways, the bogie
-truck, in one form or another, has been universally adopted from the
-beginning.</p>
-
-<p>On our home and continental lines, the modern express locomotive, with
-a four-wheel bogie truck in front, is a much longer vehicle than its
-predecessors, and its total weight is distributed over a greater
-wheel-base; but the actual weight placed upon the driving-wheels, or
-on the coupled wheels, is now very much in excess of former practice,
-and must be taken into consideration when working out the details of
-girders and cross-girders of under-line bridges. Numbers of girder
-bridges have had to be taken down and replaced with stronger
-structures, not for reasons of wear or decay, but simply because they
-were incapable of carrying with safety the modern heavy rolling loads.
-Present experience points out the expediency of providing in all new
-under-line bridges a liberal margin of strength to meet future
-developments.</p>
-
-<p><a href="#fig465">Figs. 465</a> to <a href="#fig477">479</a> are diagram sketches of a few modern types of
-locomotives, giving leading dimensions and weights, and may be found
-useful for reference when working out the necessary strengths of the
-various portions of bridge-work. Upon comparing some of the principal
-particulars with those of the earlier class, it will be noted that in
-many of the modern types the piston area has been doubled, the
-boiler-pressure doubled, and the weight of the engine doubled also.</p>
-
-<p>The engines shown in <a href="#fig465">Figs. 465 and 467</a> have great weights placed on
-the single driving-wheels, and should only be used where there is a
-very strong permanent way. With the four-wheel coupled engines, the
-weight for adhesion can be distributed between the driving and
-trailing wheels.</p>
-
-
-<div class="figcenter">
- <a name="fig468"></a>
- <img src="images/i307.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 468 through 470"
- title="Figures 468 through 470"
- />
-</div>
-
-<div class="figcenter">
- <a name="fig471"></a>
- <img src="images/i308.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 471 through 473"
- title="Figures 471 through 473"
- />
-</div>
-
-<p><a href="#fig471">Fig. 473</a> represents a very excellent type of American engine which has
-been extensively adopted in the United States for many years. The six
-coupled wheels distribute the weight over
-<!--319.png-->
-<!--320.png-->
-<!--321.png--><a name="Page_309" id="Page_309"></a><span class="pagenum">[Pg 309]</span>
-a fairly long wheel-base,
-retaining their united weight for adhesion. The four-wheel bogie truck
-in front forms a valuable path-finder to the engine, both for passing
-round curves or on straight line. This class of engine is very
-serviceable for various kinds of traffic, and is particularly suitable
-for lines where the rails and fastenings are comparatively light. In
-the example shown, the flanges are turned off the centre pair of
-coupled wheels; but for lines where the curves are of small radius,
-the flanges may be turned off the leading pair of coupled wheels,
-instead of the centre pair, to reduce the length of rigid wheel-base.
-This type of engine has latterly been introduced on various European
-and foreign railways, and recently on the Highland Railway of
-Scotland, as shown in <a href="#fig468">Fig. 470</a>. The writer has had engines of this
-class under his charge abroad, and found them to be most useful for
-heavy passenger and goods-train service. They run very steadily, are
-easy on the permanent way, and light in repairs. As they become better
-known they will be more appreciated, and will doubtless before long
-supersede in many cases the rigid six-wheel-coupled goods engine. The
-principal objection of any importance that can be raised against them
-is that on many lines the present engine turn-tables are too small for
-such long engines; but it would be far more economical in the long run
-to enlarge a few turn-tables than to continue the adoption of rigid
-engines which from their form and arrangement tend to unnecessary wear
-to themselves and the permanent way.</p>
-
-<div class="figcenter">
- <a name="fig474"></a>
- <img src="images/i310.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 474 through 476"
- title="Figures 474 through 476"
- />
-</div>
-
-
-<div class="figcenter">
- <a name="fig477"></a>
- <img src="images/i311.jpg"
- width="auto" height="500"
- alt="Illustration: Figures 477 through 479"
- title="Figures 477 through 479"
- />
-</div>
-
-<p><a href="#fig474">Fig. 476</a> shows an average sample of the ordinary six-wheel-coupled
-goods engine in use on so many of our home railways. Where the curves
-are easy and the permanent way strong, the drawback of the long rigid
-wheel-base may not be so apparent; but for a line abounding in sharp
-curves, perhaps no more destructive machine could possibly be devised
-than the ordinary six-wheel-coupled goods engine. Without any
-flexibility, forced along with great power, and too often driven at
-unnecessary high speeds, engines of this type have too small a margin
-of safety when traversing the curved portions of the road. A slight
-unevenness in the rails, or a sharp flange on the wheel may supply all
-that is wanting to cause the engine to leave the track, and the
-probability that such risks are more common than is supposed, is far
-from satisfactory. The great weight of the engine doubtless tends to
-keep it on the track, but the rapid
-<!--322.png-->
-<!--323.png--><!--324.png--><a name="Page_312" id="Page_312"></a><span class="pagenum">[Pg 312]</span>
-wear of the tyres, and of the
-inside of the rail-heads clearly demonstrate the enormous amount of
-friction and abrasion that takes place.</p>
-
-<p><a href="#fig477">Fig. 477</a> represents a type of eight-wheel-coupled engine designed for
-hauling passenger or goods trains over long lengths of heavy mountain
-inclines. The engine is a large one in every way, and of great total
-weight, but the weight is distributed over a long wheel-base and
-without imposing a greater tonnage per pair of wheels than is done in
-some of the smaller and less powerful engines. The flanges are turned
-off the leading pair and third pair of coupled wheels reducing the
-rigid wheel-base for curves to 9 feet 8 inches. The four-wheel bogie
-truck in front carries only a moderate weight, being so close to the
-coupled wheels. Engines of this description require a strong permanent
-way, as there is a total weight of 60 tons on the four pairs of
-coupled wheels standing on a wheel-base of 15 feet 6 inches.</p>
-
-<p><a href="#fig477">Figs. 478 and 479</a> are types of tank-engines in use on some of the
-narrow-gauge (3 feet) railways. In general design they are somewhat
-similar to the modern class of engine on main lines of 4 feet 8½
-inches gauge, with four-wheel bogie truck in front, and four wheels or
-six wheels coupled, but with all the parts and weights smaller, to
-suit the narrow gauge and lighter permanent way.</p>
-
-<p>The extended use of the bogie truck is an admission of its advantage
-over the fixed-wheel arrangement, both for distribution of weight and
-facility in passing round curves; but although it is now so largely
-adopted for engines and carriages on our home and continental
-railways, it is somewhat of an anomaly to find it so very rarely used
-for tenders. In the United States all the locomotive tenders&mdash;and many
-of them of very large size and weight&mdash;are carried on two four-wheel
-bogie trucks, and traverse the curves as easily as the engines. On
-this side of the Atlantic, the prevailing custom is to mount the
-tender on six rigid wheels; and as many of these tenders weigh as much
-as from 35 to 40 tons in working order, and have a rigid wheel-base of
-15 feet, it will be seen at a glance that much unnecessary friction
-and wear and tear would be avoided by substituting two four-wheel
-bogie trucks for the fixed wheels.</p>
-</div><!--end chapter six-->
-<div class="chapter">
-<!--325.png--><a name="Page_313" id="Page_313"></a><span class="pagenum">[Pg 313]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER VII.</h3>
-
-<p class="center smaller">Signals&mdash;Interlocking&mdash;Block Telegraph and Electric Train Staff Instruments.</p>
-
-<p class="p2"><strong>Signals.</strong>&mdash;Railway tradition alleges that on one of the early lines
-opened for passenger traffic, the precautions for public safety were
-considered to have been fulfilled by providing a man on horseback to
-ride along the track between the rails in the front of the locomotive
-engine, to give warning to persons strolling on the line, and to check
-the advance of the train when necessary. A very short experience of
-this method of working proved that the full capabilities of the
-locomotive could not be obtained from a restricted speed of seven or
-eight miles an hour, and a more comprehensive system of signalling had
-to be devised. By fencing in on both sides of the line, the public
-were prevented from making a general highway or promenade along the
-railway, and the problem was reduced therefore to the signalling for
-the trains alone.</p>
-
-<p>Flags of different colours, held by flagmen stationed at suitable
-places, answered the purpose for a while, or so long as the authorized
-running speed did not prevent the train being brought to a stand after
-sighting a flag warning the engine-driver to stop. As speeds were
-increased, a longer or more distant view of signals became imperative,
-and tall posts, or semaphore signals, were introduced. Well-defined
-blades or discs placed on high posts were easily worked from the
-ground-level, and could be seen for long distances, thus enabling the
-trains to be controlled or brought to a stand before reaching the
-signal. The efficiency of the principle once recognized, improvements
-and additions were made from time to time, until we have the simple
-acting tall semaphore signal so universally in use at the present
-time. The position of the signal arms or blades in the daylight, and
-the colours shown by the lamps at night, form the code of signals for
-the proper working of the train service; and as the signal arms and
-lamps are both worked simultaneously by the same gearing, it
-<!--326.png--><a name="Page_314" id="Page_314"></a><span class="pagenum">[Pg 314]</span>
-is only
-necessary to light the lamps to put the signals in complete condition
-for night-working. For some years, when the traffic was small, with
-trains at low speeds and at considerable intervals, one double-arm
-semaphore signal-post at a station was made to serve for all purposes;
-but as the train service became more frequent and more rapid, it was
-found that another semaphore or tall post signal, was necessary to
-give warning to the engine-driver some distance back before reaching
-the station or <em>home signal</em>. More particularly was this necessary at
-those stations where it was not intended that every train should stop.
-This new signal, called the <em>distant signal</em>, very soon came into
-general use. It was placed at distances varying from 400 to 800 yards
-away back from the station or home signal, and was worked by a long
-strained wire extending from the distant signal to a ground-lever
-placed near the home signal, the levers for these distant signals and
-home signals being thus near together and under the control of one
-man. More recently it was found necessary to introduce another
-important wire-worked signal called a <em>starting signal</em>, which is
-placed at the outgoing or departure end of the passenger platforms,
-lines, or station sidings, to prevent any train or engine starting or
-proceeding on its journey until such starting signal is lowered to
-indicate that the line is clear.</p>
-
-<p>These simple, independent, hand-worked semaphore signals did good
-service for many years, but being independent and in no way physically
-connected with one another at junctions, or stations, or with the
-switches they were intended to control, it was quite possible for
-mistakes to arise where everything depended upon the accuracy and
-prompt decision of the signalman. The possibility that such mistakes
-could occur, and the certainty that they actually did occur, and too
-often with most disastrous results, led gradually to the grouping and
-interlocking of a large number of signal levers and switch levers
-together in one signal cabin. The advantages of the concentrating and
-interlocking of signals and switches are twofold. In the first place,
-one man in the signal cabin can work and control the levers for a
-large number of switches and signals, where formerly several men were
-required to be located at various places in the station-yard; but the
-second, and by far the most important advantage, is that with proper
-interlocking arrangements it is practically impossible to give
-conflicting signals.</p>
-
-<p><!--327.png--><a name="Page_315" id="Page_315"></a><span class="pagenum">[Pg 315]</span>
-With a modern interlocking frame, and assuming the normal position of
-all the signals to be at <em>danger</em>, then before a signal can be
-lowered for an approaching engine or train all the switches and
-corresponding signals, from any lines or sidings connecting with the
-line to be signalled <em>clear</em> must first be set so as to prevent
-any engine or train coming out of such connecting lines or switches on
-to the line to be made clear. In a similar manner, before the points
-and signals can be set to permit an engine or train to pass from a
-siding on to the main line all the necessary signals must first be set
-to <em>danger</em> to prevent the approach in either direction of any
-engine or train on the main line about to be occupied. The mechanical
-arrangements of the interlocking frame are so exact and complete as to
-effectually prevent any but the proper combination being made. An
-untrained or inexperienced signalman might inadvertently attempt to
-pull over a wrong lever, only to find it securely locked and immovable
-under the control of other levers. The proper sequence of levers must
-be made, and the accurately adjusted mechanism automatically prevents
-mistakes which formerly occurred with the old hand-worked signals from
-the oversight or confusion of the signalman.</p>
-
-<p>The interlocked switches or points are worked from the signal-cabin by
-light wrought-iron tubing (termed rodding) or channel-shaped iron bars
-supported on fixed iron rollers, and the signals by galvanized wires
-running over light pulleys. Modern signals are always weighted at the
-signal-post, so that in the event of the breaking of the pulling-wire
-they will fly back to their normal position of danger.</p>
-
-<p>The facility and precision secured by the interlocking machinery
-enabled other valuable accessories to be introduced for the more
-complete signalling and protection of train-working. Amongst these may
-be mentioned the facing-point bolt-lock and rocking-bar,
-signal-detectors at points, and throw-off or trap points.</p>
-
-<p>With the old-fashioned hand-worked switches the man standing alongside
-could see whether the sliding-rails were properly closed, and also
-when the last vehicle of the train had passed over them; but when
-important main-line-facing switches or points are worked by rodding
-from a signal-cabin some distance away, it is necessary to have some
-reliable means to ensure that the sliding-rails are actually brought
-close home, and also to prevent
-<!--328.png--><a name="Page_316" id="Page_316"></a><span class="pagenum">[Pg 316]</span>
-the switches being moved again until
-the entire train has passed over them. A set of switches may be
-carefully made and work well, but it is quite possible for some
-fracture or obstruction, to intervene and prevent them closing
-properly. If a train or engine were passing through them in a trailing
-direction, as indicated in <a href="#fig345">Fig. 345</a>, the wheels would most probably
-force the sliding-rail home, and no disturbance would arise. If,
-however, the train were coming in the opposite or facing direction,
-the chances are that some of the wheels would take one road and some
-the other, and cause a derailment. The same casualty would occur if
-the switches were moved during the passage of the train.</p>
-
-<p>To guard against the above contingencies, the facing-point bolt-lock
-and rocking-bar have been introduced. The system is applied in various
-forms, but the arrangement shown in <a href="#fig480">Fig. 480</a> will explain the
-principle generally.</p>
-
-<p>A strong casting, <strong>A</strong>, is securely bolted to the top of the sleeper
-carrying the chairs on which rest the point ends of the sliding-rails.
-This casting has an internal groove or chamber formed for its entire
-length from <strong>C</strong> to <strong>D</strong>, as indicated by the dotted lines, and in which
-slides the locking-bolt <strong>B</strong>. The point ends of the switch or
-sliding-rails are connected by the transverse rod <strong>E</strong>, which is forged
-into a vertical bar form for that portion of its length, which passes
-through the opening, <strong>F</strong>, prepared for it in the casting <strong>A</strong>. In this
-vertical bar a hole or slot is cut to correspond to the exact size of
-the locking-bolt <strong>B</strong>, and at a distance to suit the sliding-rails when
-pulled over to their properly closed position. This locking-bolt, <strong>B</strong>,
-will not pass through the hole in the vertical bar until the
-sliding-rails are quite close home, and when once through the hole the
-sliding-rails cannot be moved until the locking-bar is withdrawn. In
-some cases two holes or slots are cut in the vertical bar to enable
-the points to be bolt-locked for both directions.</p>
-
-<p>The rocking-bar is designed to prevent the withdrawal of the
-locking-bolt before all the vehicles have passed over the points.</p>
-
-<div class="figcenter">
- <a name="fig480"></a>
- <img src="images/i317.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 480 through 483"
- title="Figures 480 through 483"
- />
-</div>
-
-<p>This rocking-bar consists of an angle iron or tee-iron bar of a length
-equal to the longest wheel-base of the rolling-stock, and is carried
-on short pivoted arms working in cast-iron or wrought-iron brackets
-secured to the rails as shown in <a href="#fig480">Fig. 481</a>. The pivoted arms have a
-movement backward or forward, and when at either the one or the other
-extremity, the upper surface
-<!--329.png--><!--330.png--><a name="Page_318" id="Page_318"></a><span class="pagenum">[Pg 318]</span>
-of the rocking-bar is sufficiently below
-the top of the rail to be well clear of the flange of any passing
-wheel; but while changing from the one to the other position, and when
-the pivoted arms are vertical, or at half-stroke, the upper surface of
-the rocking-bar is about level with the top of the rail, and right in
-the pathway of the wheel-flange. It is evident, therefore, that when
-the pivoted arms are set in the forward or backward position, and one
-of the wheels of a train or vehicle has passed on to the rail over the
-rocking-bar, the latter cannot be changed or raised and pulled over to
-the opposite extremity so long as any one of the wheels of the train
-or vehicles remain over the rocking-bar.</p>
-
-<p>As the same ground-crank which pulls over the pivoted arms from
-backward to forward also withdraws the locking-bolt <strong>B</strong>, the latter is
-thus held securely in the hole or slot of the transverse rod, <strong>E</strong>,
-until all the wheels of the train have passed off the rocking-bar. The
-operation of changing the points from one road to another is very
-simple. By means of the rodding <strong>G</strong>, worked by a lever in the
-signal-cabin, the locking-bolt <strong>B</strong> is first withdrawn from the slot;
-the points are then pulled over into the reverse position by the
-rodding <strong>H</strong>, and the locking-bolt <strong>B</strong> is again set back into one of
-the slots by the rodding <strong>G</strong>. Sometimes, for economy, the points,
-bolt-lock, and rocking-bar, are all three worked by one lever in the
-signal-cabin, and one set of rodding on the ground, as shown in <a href="#fig480">Fig.
-482</a>; but the arrangement is neither so perfect nor so secure as that
-shown in <a href="#fig480">Fig. 480</a>. Where there are two sets of rodding and gearing,
-the failure or breaking of either of them prevents the complete
-combination being made, and indicates at once to the signalman that
-something is wrong; but when there is only one set of rodding a
-breakage may occur without giving any tangible evidence to the
-signalman of the defect, and he may proceed to pull over his signal
-lever in ignorance that the points have not been properly made and
-bolted. To avoid an accident taking place from the failure of either
-rodding or gearing, the signal-detector has been devised, so as to
-prevent the possibility of pulling over the signal wire until the
-points and locking-bar are both in their proper positions.</p>
-
-<p>The signal-detector is applied in several forms; the one shown in
-<a href="#fig480">Figs. 480 and 483</a> will explain the principle on which its efficacy
-depends. A transverse rod, <strong>I</strong>, attached to the sliding-rail,
-<!--331.png--><a name="Page_319" id="Page_319"></a><span class="pagenum">[Pg 319]</span>
-extends
-out beyond the rails, and is formed into a flat bar or plate, <strong>J</strong>,
-sliding through the guide-holes <strong>K</strong>, <strong>K</strong> in the casting <strong>L</strong>. Short
-upright levers, <strong>M</strong> and <strong>N</strong>, work on trunnions fixed in the casting,
-and to <strong>M</strong> and <strong>N</strong> are attached the wires leading from the
-signal-cabin and continuing on to the signal-posts, as shown in
-elevation in <a href="#fig480">Fig. 483</a>. Two slots are cut in the plate <strong>J</strong> to receive
-the curved arms of the levers <strong>M</strong> and <strong>N</strong> when they are drawn
-downwards to pull off the corresponding signals. Neither of the
-levers, <strong>M</strong> or <strong>N</strong>, can be drawn over unless there is a slot
-immediately under the curved arm into which it can enter. When there
-is solid plate under a curved arm, the short lever cannot be pulled
-over, and the signal therefore remains at danger. The slots in the
-plate <strong>J</strong> are spaced so that one will be brought into position for one
-of the curved arms, when the points are close home for the main line,
-and the other slot for the other curved arm, when the points are set
-for the branch line or siding. The two slots cannot be under the two
-curved arms at one and the same time, as one of the signals
-corresponds to the main line and the other to the branch line or
-siding.</p>
-
-<p>In some forms of signal-detector the transverse rod <strong>I</strong> is joined on
-to a vertical bar which slides through guide-holes in a casting
-something similar to the arrangement shown in the casting <strong>L</strong>.
-Longitudinal guide-holes, parallel to the line of rails, are made in
-the casting a little above the transverse rod-bar, and through the
-longitudinal guide-holes slide two vertical bars which are attached
-to, and form part of, the wire connections to the two signals. The
-wire bars have each a small tongue or rectangular fin forged on to the
-under side of the bar, and there is one corresponding channel cut in
-the transverse rod-bar. When the switches are properly closed in one
-position, the channel cut of transverse bar will be opposite one of
-the <a name="wire"></a>wire bar fins, and will allow one of the signals to be pulled over,
-but the other wire bar cannot be moved. The closing of the switches in
-the reverse position moves the channel cut so as to allow the other
-wire bar to be pulled through, but as there is only one channel cut in
-the transverse bar, only one signal can be pulled over for each
-position of the switches.</p>
-
-<div class="figcenter">
- <a name="fig484"></a>
- <img src="images/i320.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 484 through 497"
- title="Figures 484 through 497"
- />
-</div>
-
-<p>Throw-off or <em>trap points</em>, are introduced to throw an engine or train
-off the rails of a siding on to the ballast, and so avoid a collision
-with any other train which may be standing or passing on the line of
-rails with which such siding forms a connection.
-<!--332.png--><!--333.png--><a name="Page_321" id="Page_321"></a><span class="pagenum">[Pg 321]</span>
-<a href="#fig484">Fig. 484</a> is a diagram
-sketch of the arrangement, in which the
-main-line points are indicated by the letter <strong>A</strong>, and the trap points
-by the letter <strong>B</strong>; one series of rodding actuated by one lever in the
-signal-cabin works both the main-line points and the trap points at
-the same time and by the same movement. The connections are so made
-that when the points <strong>A</strong> are set for the passage of trains on the main
-line, the trap points <strong>B</strong> are set open to throw off on to the ballast,
-as shown in <a href="#fig484">Fig. 484</a>; and when the main-line points <strong>A</strong> are set to
-allow a train to pass from the siding on to the main line, the trap
-points <strong>B</strong> are closed, as shown on <a href="#fig484">Fig. 485</a>. A disc or other signal,
-worked or interlocked with the points, is placed near <strong>B</strong> to notify
-the engine-driver when he may pass out of the siding on to the main
-line; but should he from any cause proceed before the points are
-properly set and the corresponding signal given, his engine would run
-off at the ends of the rails <strong>C</strong>, <strong>C</strong>, and be derailed on to the
-ballast. The inconvenience caused by such derailment would be trifling
-compared with what might result from a collision with a train standing
-or passing on the main line. In some cases the siding is continued
-onwards for a considerable distance from the trap-point rails <strong>C</strong>,
-<strong>C</strong>, as indicated by the dotted lines <strong>D</strong> <strong>D</strong>, and terminates with a
-dead end. When this arrangement can be adopted, derailment is
-obviated, and the engine is brought to a stand by a buffer-stop at the
-end of siding. On no account should trap points be placed close to the
-top edge of a high embankment, or up to the abutment or wing walls of
-an under-line bridge, where an engine running through them
-accidentally might fall down a considerable height, and cause serious
-results. All sidings joining on to main lines should be trapped as
-above described, and when properly signalled and interlocked in the
-signal-cabin, the traffic-working can be carried on with increased
-facility and security.</p>
-
-<p><a href="#fig484">Fig. 486</a> is a sketch of an average sample of an ordinary single-arm
-wooden signal-post, with signal-arm, lamp, spectacles, ladder, and
-gearing complete for wire connection to signal-cabin. When the arm
-stands out in the horizontal position, representing the <em>danger</em> or
-stop signal, the red spectacles will be in front of the lamps, and
-will show a red light to an approaching train. When the arm is
-lowered, as indicated by the dotted lines, the second spectacle will
-be in front of the lamps, and will show either a white or green light
-(according to the accepted code) as
-<!--334.png--><a name="Page_322" id="Page_322"></a><span class="pagenum">[Pg 322]</span>
-an <em>all-right</em> signal for the
-train to proceed. For many years a white light was adopted for the
-all-right signal, but latterly, to prevent confusion with other white
-lights about a station, there has been an increasing disposition to
-use a green light as an all-right signal. Several railway companies
-have already effected the change, and others have arranged to follow
-their example. The counter-weight <strong>W</strong> keeps the signal-arm to the
-danger position, except when it is raised by the pulling over of the
-signal-wire from the signal-cabin working over the pulley <strong>P</strong>. Should
-the wire break when being pulled, the weight <strong>W</strong> falls down to the
-stop-plate, and the signal-arm rises to danger. The signal-posts may
-be of wood, wrought-iron, steel lattice-work, or cast-iron.</p>
-
-<p>The arms of <em>distant signals</em> should be cut to a fish-tail shape, as
-in <a href="#fig484">Fig. 487</a>, to distinguish them from other signals. Goods-line
-signals should have a thin sheet-iron ring, as in <a href="#fig484">Fig. 488</a>. Sometimes
-purple glass is used instead of red glass for the spectacles of goods
-signals. Letters or numbers may be attached to signal-arms to signify
-the lines or sidings to which they correspond. Special signals are
-sometimes made with the arm working on a centre pin, as in <a href="#fig484">Fig. 489</a>.</p>
-
-<p>At junctions or places where two or three signals have to be fixed
-near together, it is customary to carry them on a bracket signal-post,
-as in <a href="#fig484">Figs. 490 and 491</a>. The former represents the home signals at an
-ordinary junction, the taller signal being for the main line and the
-lower one for the branch line. <a href="#fig484">Fig. 491</a> shows the home signals at a
-junction where there is one line turning out of the main line to the
-left and another to the right. The taller signal in this case also
-serves for the main line and the two lower signals for the branch
-lines.</p>
-
-<p>In important station-yards, where there are a large number of lines
-and sidings running side by side, it is not always convenient or
-possible to place the respective signal-posts in suitable positions
-between the lines. To overcome the difficulty, the signals are erected
-on light overhead lattice girders, as shown in <a href="#fig484">Fig. 492</a>. In some
-cases, for want of a better position, or to obtain a more
-comprehensive view of the lines and signals, the signal-cabin is built
-on lattice girders, as in <a href="#fig484">Fig. 493</a>.</p>
-
-<p>Ground or <em>disc signals</em> are fixed at the ground-level, and are worked
-in conjunction with trap points or outlet switches from sidings. In
-some cases they are worked direct by a connecting-rod
-<!--335.png--><a name="Page_323" id="Page_323"></a><span class="pagenum">[Pg 323]</span>
-from the
-switches, and serve merely as indicators to show whether the switches
-are lying for or against an engine passing out of the siding. In other
-cases they are worked independently from the signal-cabin by a
-separate lever and wire connection, the interlocking being so arranged
-that the lever working the switches must be pulled over before the
-lever working the disc signal can be moved. In one type the disc
-signal is fixed to a short vertical axis, as shown in <a href="#fig484">Fig. 494</a>, and by
-means of a cranked arm is made to rotate a quarter of a circle, so as
-to exhibit either a stop or advance signal according to the position
-in which the switches are lying. In another type, the lamp is fixed,
-and the red disc, with a red glass in the centre, is made to assume a
-horizontal or vertical position by a rod and crank, as shown in <a href="#fig484">Fig.
-495</a>.</p>
-
-<p>A simple arrangement of rodding and rollers for switch connections is
-shown in <a href="#fig484">Fig. 496</a>, the number of sets of rodding being determined by
-the number of connections to be made. <a href="#fig484">Fig. 497</a> is a rodding
-compensator, to compensate or adjust for the difference in length of
-the rodding arising from variations in the temperature. The
-compensator may be used either vertically or horizontally, according
-to space or circumstances.</p>
-
-<p>Strong wrought-iron or steel cranks of different angles will be
-required when changing the direction of the rodding, or connecting to
-switches and facing point-locks. They must be firmly secured to strong
-timber framework well bedded in the ballast. For cranks working
-switches and bolt-locks, it is better to use extra long timbers under
-the rails instead of the ordinary sleepers. Cross-pieces can be bolted
-to the ends of the long timbers, and the cranks placed practically on
-the same timbers carrying the permanent way. By this means the rails
-and cranks can always be maintained in their proper relative positions
-as to distance, line, and level.</p>
-
-<p>Without a large series of diagrams it would be impossible to
-adequately describe the extent of signalling and interlocking required
-at large terminal stations and important roadside stations, but one or
-two simple examples may serve to illustrate the general principles.</p>
-
-<div class="figcenter">
- <a name="fig498"></a>
- <img src="images/i324.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 498 and 499 "
- title="Figures 498 and 499"
- />
-</div>
-
-<p><a href="#fig498">Fig. 498</a> represents the modern grouping of signals considered
-necessary at an ordinary double-line junction, showing all the signals
-at their normal or <em>danger</em> position. The numbers marked on each
-indicate the numbers of the levers in the interlocking
-<!--336.png--><!--337.png--><a name="Page_325" id="Page_325"></a><span class="pagenum">[Pg 325]</span>
-frame of the
-signal-cabin. Four distinct sets of trains have to be dealt with at
-this class of junction, and the interlocking must be so arranged that
-when the signals are lowered for the advance of any one train, no
-conflicting signals can be given to any other train.</p>
-
-<p>Assuming a train approaching from <strong>A</strong>, which has to continue on the
-main line past <strong>B</strong> on towards <strong>C</strong>, then the levers in the signal-cabin
-must first be pulled over to set the points 9 and bolt-lock 8 in
-proper position for the main line; and this operation will release the
-levers which have to be pulled over to lower the signals 5, 4, and 6,
-but at the same time will lock, and prevent the pulling over of the
-levers or lowering of the signals 2 and 1 for a train from <strong>A</strong> to <strong>B</strong>
-and <strong>D</strong>, or of the signals 14 and 15 for a train from <strong>D</strong> to <strong>B</strong> and
-<strong>A</strong>. The levers will, however, be free to pull over for setting the
-points 12 and lowering the signals 16, 17, and 13 for a train on the
-main line from <strong>C</strong> to <strong>B</strong> and <strong>A</strong>.</p>
-
-<p>In a similar manner, assuming a train approaching from <strong>D</strong>, which has
-to continue up to the main line at <strong>B</strong> and on towards <strong>A</strong>, then the
-lever in the cabin must first be pulled over to set the trailing
-points 12 in proper position; and this operation will release the
-levers which have to be pulled over to lower the signals 14 and 15,
-but at the same time will lock, and prevent the pulling over of the
-levers or lowering of the signals 5 and 4 for a train from <strong>A</strong> to <strong>B</strong>
-and <strong>C</strong>, or of the signals 16 and 17 for a train from <strong>C</strong> to <strong>B</strong>
-and <strong>A</strong>. The levers will, however, be free to pull over for setting
-the points 9 and bolt-lock 8 and lowering the signals 2 and 1 for the
-passage of a train on to the branch line from <strong>A</strong> to <strong>B</strong> and <strong>D</strong>.</p>
-
-<p>For a train from <strong>C</strong> to <strong>B</strong> and <strong>A</strong>, the levers 12, 16, 17, and 13 would be
-required, and these would lock levers 14 and 15, and prevent the
-approach of any train from <strong>D</strong> to <strong>B</strong>, but they would leave free the
-levers necessary either for a train from <strong>A</strong> to <strong>B</strong> and <strong>C</strong>, or for a train
-from <strong>A</strong> to <strong>B</strong> and <strong>D</strong>, but only one of them at a time, the setting of the
-one series locking the other series.</p>
-
-<p>A train from <strong>A</strong> to <strong>B</strong> and <strong>D</strong> would require the proper setting of the
-points 9, bolt-lock 8, and signals 2, 1, and 3; and these would lock 5
-and 4, but would leave free the levers necessary either for a train
-from <strong>C</strong> to <strong>B</strong> and <strong>A</strong>, or for a train from <strong>D</strong> to <strong>B</strong> and <strong>A</strong>, but only one of them
-at a time.</p>
-
-<p>The cross-over road from the <span class="muchsmaller">UP</span> to <span class="muchsmaller">DOWN</span> main line, near the
-<!--338.png--><a name="Page_326" id="Page_326"></a><span class="pagenum">[Pg 326]</span>
-letter <strong>B</strong>
-on sketch, is only intended for use in case of break-down or
-accidents, and the normal position of the points is to lie clear for
-the passage of trains on the main lines. To use the cross-over road,
-the whole of the signals must first be set to <em>danger</em> before the
-points 7 and 7 can be opened to permit the passage of an engine or
-train from the one main line to the other.</p>
-
-<p>The starting signals 6 and 3 should be placed sufficiently far away
-that the longest passenger or goods train may stand between them and
-the clearance points at <strong>G</strong> and <strong>E</strong>. These starting signals are of great
-service to train-working at junctions. Supposing a main-line train
-from <strong>A</strong> arriving at <strong>B</strong> before the section from <strong>B</strong> to <strong>C</strong> was clear, such
-train could be brought to a stand at signal 6, and remain there while
-another train from <strong>A</strong> was allowed to pass <strong>B</strong>, and proceed onwards
-towards <strong>D</strong>; or a branch-line train from <strong>A</strong> to <strong>D</strong> could be brought to a
-stand at 3, to allow a main-line train to proceed onwards from <strong>A</strong> to <strong>B</strong>
-and <strong>C</strong>. The starting signal 13 should be placed well in advance of the
-cross-over road to control anything passing from one line to the
-other.</p>
-
-<p><a href="#fig498">Fig. 499</a> shows the modern grouping of signals for an ordinary
-single-line junction. The arrangement is almost practically the same
-as for the double-line junction shown in <a href="#fig498">Fig. 498</a>, there being the
-same four distinct sets of trains to be controlled, but not any
-cross-over road. The signal-cabin is placed on the main line, a little
-in advance of the facing points, and a well-fenced-in gangway, the
-same height as the engine footplate, is carried out the proper
-distance from the rails, on which the signalman can stand to hand over
-or receive the train staff from the engine-driver when passing.</p>
-
-<p>At stations and places where there are several sidings and lines
-connecting with the main lines, at considerable distances apart, it
-will be necessary to have two or more signal-cabins placed in suitable
-positions, not only for expediting the working of the constant
-shunting movements, but also to insure that there is a signal-cabin
-within the regulation distance of all facing points on the main line.
-So far as the main line is concerned, the interlocking of these cabins
-must be connected, the one with the other, by slotting, or co-acting
-gearing, in such manner that the cabin in advance shall always be able
-to control the cabin in the rear in the lowering of the main-line
-signals for an approaching train. <a href="#fig376">Fig. 376</a> is a diagram sketch
-<!--339.png--><a name="Page_327" id="Page_327"></a><span class="pagenum">[Pg 327]</span>
-of a
-typical double-line roadside station with two signal-cabins. The <span class="muchsmaller">NORTH</span>
-cabin has to work the signals and points in connection with the
-goods-shed, goods-sidings, and market branch, and the <span class="muchsmaller">SOUTH</span> cabin,
-those in connection with the coal and cattle sidings; and each of the
-cabins to work the signals and points of that portion of the main line
-adjoining its own cabin. For siding working, each cabin is quite
-distinct and independent of the other, but for main-line working the
-lowering of the signals can only be effected by the joint operation or
-co-acting of both cabins.</p>
-
-<p>Assuming a train approaching from <strong>A</strong> to proceed in the direction towards
-<strong>B</strong>, then, before the signalman in the <span class="muchsmaller">NORTH</span> cabin can lower the
-<span class="muchsmaller">UP</span> home-signal <strong>C</strong>, the signalman in the <span class="muchsmaller">SOUTH</span> cabin must
-first pull over his lever and release the slot which retains the signal <strong>C</strong> at
-<em>danger</em>, and in doing so the levers in his own cabin will stand
-locked, and prevent the lowering of the signal <strong>D</strong>, or opening of points
-<strong>E</strong> to allow access from the sidings to <span class="muchsmaller">UP</span> main line. The cross-over
-road <strong>F</strong> <strong>G</strong> will also be locked for main line clear. When the slot has
-been released from signal <strong>C</strong>, the signalman in <span class="muchsmaller">NORTH</span> cabin can lower
-the <span class="muchsmaller">UP</span> home signal <strong>C</strong>, but before he can pull over the lever for this
-purpose he must first lock the points <strong>H</strong>, to prevent access from the sidings
-to the <span class="muchsmaller">UP</span> main line, and also the points <strong>K</strong> <strong>L</strong> of the
-cross-over road, to keep the main line clear. A similar operation has to be gone
-through for a train approaching from <strong>B</strong> to proceed in the direction towards
-<strong>A</strong>, when the signalman in <span class="muchsmaller">NORTH</span> cabin must first withdraw the slot
-from the <span class="muchsmaller">DOWN</span> home-signal <strong>M</strong> before the signalman in the
-<span class="muchsmaller">SOUTH</span> cabin can lower that signal. A small automatic disc is placed in the
-cabin to indicate to the signalman when the slot has been withdrawn by
-his colleague in the neighbouring cabin, and for facility of working,
-the two cabins are usually placed in communication with each other by
-telegraph or telephone.</p>
-
-<p>At some stations similar to the above, where there is a very frequent
-train service, with several of the trains running through without
-stopping, it is the practice to have a second or lower arm to the home
-signals <strong>C</strong> and <strong>M</strong>, as shown on the diagram, these lower arms being
-only <em>pulled off</em> for through or non-stopping trains, as an indication to
-the engine-driver that the line is clear in the section ahead.</p>
-
-<p>In addition to the leading signals shown in the sketches,
-<!--340.png--><a name="Page_328" id="Page_328"></a><span class="pagenum">[Pg 328]</span>
-there are
-shunting signals for the movement and marshalling of
-trains&mdash;setting-back signals in connection with the making up of
-passenger trains; taking on or off passenger carriages; or moving out
-empty passenger carriages; and many other special signals which become
-necessary for the working of a large and complicated train service.</p>
-
-<p>The above simple diagrams will explain some of the principal
-requirements to be kept in view when working out signalling
-arrangements. Where the lines and sidings are very numerous, as at
-important junctions and large terminal stations, the signalling
-becomes very intricate, and may require three or four cabins, slotted
-together in such manner that the necessary co-acting may be insured
-for the proper controlling of the mainline signals. Many of these
-signal-cabins contain a large number of levers, some of them having as
-many as a hundred, and a few of them two hundred and forty levers, or
-more, all of them so carefully arranged that no conflicting signal can
-be given. Not only has much skill to be exercised in the accurate
-adjustment of the interlocking machinery, but much study must be
-devoted to determine the exact duty of every lever, for the locking or
-releasing of other levers.</p>
-
-<p>Signal-cabins may be built of stone, brick, or wood. They should be
-roomy, well ventilated, and have abundance of light. Every
-signal-cabin should be placed in the position from which the signalman
-can obtain the best view of the signals and points under his charge.
-The height of the cabin floor will depend upon any obstacles that may
-intervene between the cabin and the signals, such as over-line
-bridges, station roofs, buildings, or other obstructions. Sometimes
-the floor has to be kept as low as five feet above rail-level, to
-secure a line of sight under the over-line bridges; and in others the
-floor has to be raised twenty, or even thirty feet above rail-level.</p>
-
-<div class="figcenter">
- <a name="fig500"></a>
- <img src="images/i329.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 500 through 502 and 506 - 508"
- title="Figures 500 through 502 and 506 - 508"
- />
-</div>
-
-<p><a href="#fig500">Figs. 500, 501, and 502</a> show plan, transverse section, and elevation
-of a signal-cabin suitable for a small roadside station. The lower
-story and chimney-stack are of brick, and the upper story of wood,
-with slated roof. There is room for an interlocking frame of twenty or
-twenty-five levers, and space at the end of the cabin for the
-block-telegraph instruments, or electric train-staff instruments. The
-roof-work is open up to the slateboards, to obtain as much air
-capacity as possible. In the transverse section a winch for working
-mechanical gates is
-<!--341.png--><!--342.png--><a name="Page_330" id="Page_330"></a><span class="pagenum">[Pg 330]</span>
-shown at the end of the interlocking frame. There
-is a liberal amount of glass, and two or three sliding windows, which
-the signalman can open to enable him to speak to the engine-drivers or
-others during shunting operations. The lower story of the cabin can be
-utilized for trimming lamps and keeping a small supply of coals and
-other stores. When working after dark the lamps in the cabins should
-be well protected by shades, to prevent the lights being seen by
-engine-drivers, and mistaken for signals.</p>
-
-<p class="p2"><strong>Interlocking.</strong>&mdash;There are several systems of interlocking, each of them
-varying considerably in the form and mode of application, but all of
-them having the same general object of securing or releasing the
-necessary levers for each combination of signalling movements. A brief
-description of one of the systems will explain the order in which the
-movements have to be made, and the security which can be obtained by
-the locking.</p>
-
-<p><a href="#fig503">Figs. 503, 504, and 505</a>, are sketches illustrating one of the types of
-wedge and tappet interlocking. Each lever works on a fulcrum or pinion
-as at <strong>A</strong>, and has a lower arm <strong>B</strong> for lifting the rods leading off to
-points or signals, and an arm <strong>C</strong> to carry a counterweight when necessary.
-Cast-iron braces <strong>D</strong> are placed at convenient distances between the series
-of levers to carry the top frame <strong>E</strong> on which the lever floor casing
-<strong>F</strong> is bolted. This casing is continuous from end to end of the locking
-frame, with the exception of the narrow openings through which the
-levers travel when moving backwards or forwards. The sleeve-block
-<strong>G</strong>, resting in the depressed portions of the arc, retains the lever in
-position. When taking hold of the main lever <strong>L</strong>, the signalman’s hand
-draws the small side lever <strong>M</strong>, close to the main lever, and raises the
-sleeve-block <strong>G</strong> sufficiently high to pass over the top of arc <strong>F</strong>, the
-lever <strong>L</strong> can then be pulled or pushed over, and the block <strong>G</strong> will fall
-into the depression at the end of the stroke when the hand is removed.
-<strong>N</strong> is a tappet or thin flat bar attached to the main lever, and which
-works backwards or forwards between the wedges in the wedge frame <strong>O</strong>.
-The wedges move horizontally between guide pieces, and work either
-singly or are connected by the lower slide bars to other wedges some
-distance away on the frame according to the position of the levers
-which have to stand or move in unison for the releasing or locking. A
-strong cover is placed over the wedge frame to keep out the dirt.</p>
-
-<div class="figcenter">
-<!--343.png--><a name="Page_331" id="Page_331"></a><span class="pagenum">[Pg 331]</span>
- <a name="fig503"></a>
- <img src="images/i331.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 503 through 505"
- title="Figures 503 through 505"
- />
-</div>
-
-<p><!--344.png--><a name="Page_332" id="Page_332"></a><span class="pagenum">[Pg 332]</span>
-<a href="#fig503">Figs. 504 and 505</a> show plan views of four levers in a signal cabin
-taken just above the level of the tappets. In <a href="#fig503">Fig. 504</a>, all the levers
-are in their <em>normal</em> or forward position, with the home and distant
-signals at <em>danger</em>, and the facing points leading into loop or siding
-lying for main line. Previous to the approach of a train on the main
-line, the home and distant signals have to be lowered, and will
-require the pulling over of levers 1 and 2; but these levers cannot of
-themselves be moved, as the wedges <strong>P</strong> and <strong>Q</strong> are locked by the straight side
-of lever 3. The operation would therefore be as follows:&mdash;points lever
-4 being set in its normal position for the main line would remain
-forward, lever 3 working the facing point bolt-lock would be pulled
-over, and in doing so would move the wedge <strong>R</strong> to the right into the
-recess of tappet of lever 4, locking that lever, and presenting the
-recess of its own tappet ready to receive the wedge <strong>Q</strong>. Lever 2 can
-then be pulled over, and will move the wedge <strong>Q</strong> to the right into the
-recess of tappet of lever 3, and present its own recess for wedge <strong>P</strong>.
-The pulling over of lever 1 completes the series, by moving the wedge
-<strong>P</strong> over to the right into the recess of tappet of lever 2. <a href="#fig503">Fig. 505</a>
-shows the positions of the tappets and wedges with the levers 1, 2,
-and 3, pulled over to make the combination described. Upon
-examination, it will be seen that levers 2, 3, and 4, are all securely
-locked, the points cannot be moved, nor the facing point bolt-lock
-withdrawn, nor the home signal changed until the lever 1 is pushed
-over again into its normal or <em>danger</em> position. To restore the levers
-to their forward position, they must be set back in the reverse order
-to which they were pulled over. To simplify the explanation, only four
-levers are shown in the above sketches, but the principle is
-constantly extended out to a very large number of levers, and in many
-cases necessitates the introduction of several rows of wedges as
-indicated by the dotted lines. In some instances a combination is
-effected by pulling a certain lever only half over. In some systems
-the preliminary action or spring handle locking is adopted, in which
-the locking is actuated by the small side lever, similar to the one
-marked <strong>M</strong> on <a href="#fig503">Fig. 503</a>. The advocates of this arrangement claim
-increased security and precision in the interlocking, while on the
-other hand it is alleged that the mechanism is rendered more
-complicated without any corresponding advantage.</p>
-
-<p class="p2"><strong>Detached Lock.</strong>&mdash;Sometimes there is in the vicinity of a
-<!--345.png--><a name="Page_333" id="Page_333"></a><span class="pagenum">[Pg 333]</span>
-railway station,
-a siding which is too far away to be worked direct from a signal
-cabin, and not sufficiently used to warrant a separate cabin. Such
-sidings can be worked by a small ground frame opened or locked by a
-special key attached to the interlocking machinery in the adjoining
-signal cabin on a double-line railway, or attached to the train staff
-on a single line.</p>
-
-<p><a href="#fig500">Fig. 506</a> shows the arrangement applied to a double line with the
-outlying siding turning out of the <span class="muchsmaller">UP</span> main line, the points lying in a
-trailing direction for the running trains. Before the special and
-<em>only</em> key can be withdrawn from its seat in the interlocking frame of
-the signal cabin, all the <span class="muchsmaller">UP</span> main line signals must be set to
-<em>danger</em>, and cannot be moved from <em>danger</em> until the key is restored
-to its proper seat again. When the key is removed from the signal
-cabin, it can be taken to the ground frame at <strong>A</strong>, inserted in the key
-opening, and by turning it partly round, will release the bar which
-locks the levers of the facing point bolt-lock and the points. When
-these two levers are free the points can be opened, and vehicles moved
-into or out of the
-siding <strong>B</strong> <strong>C</strong>, but the special key cannot be withdrawn from the ground-frame
-<strong>A</strong>, until the points and facing point bolt-lock are put back again into
-their normal position for main line working. When the operations at
-the siding are completed, the special key can be removed, and taken
-back to its proper place in the signal-cabin, and ordinary working be
-resumed.</p>
-
-<p><a href="#fig500">Fig. 507</a> shows the application of the detached locks on a single line,
-and is a sketch of a portion of railway on which
-there is a small station <strong>B</strong>, with a goods siding <strong>F</strong> <strong>G</strong>, where the
-traffic is too small to require anything more than ground frames and
-detached locks. An engine-driver before leaving the station <strong>A</strong>,
-receives a train staff, which gives him possession of the line as far
-as <strong>C</strong>, including of course the intermediate station <strong>B</strong>, and this staff
-he must carry with him and hand over to the signalman on his arrival
-at the end of the section at <strong>C</strong>. At each of the points <strong>D</strong> and <strong>E</strong> is
-placed a two lever ground frame, similar to the one shown in <a href="#fig500">Fig. 506</a>,
-and attached to the train staff is a key, which will operate either of
-the two ground frames, but only one at a time, as the key must be
-inserted before the levers can be moved. When the train is proceeding
-in the direction from <strong>A</strong> to <strong>C</strong>, it will be more convenient to shunt
-vehicles into or out of the siding <strong>F</strong> <strong>G</strong>, by means of the points
-<strong>E</strong>, but when proceeding from <strong>C</strong> to <strong>A</strong>, the points <strong>D</strong> will be more convenient.
-<!--346.png--><a name="Page_334" id="Page_334"></a><span class="pagenum">[Pg 334]</span>
-Whichever of the points be used, they must be set, and bolt locked for
-the main line before the train staff and its key can be withdrawn from
-the ground frame and restored to the engine-driver. As the siding is
-<em>trapped</em> at <strong>F</strong> and <strong>G</strong>, it is impossible for any vehicles to be moved out
-on to the main line except through the medium of the train staff and
-key. The same arrangement of detached lock is equally available for a
-single siding with only one set of points.</p>
-
-<p class="p2"><strong>Electric Repeater.</strong>&mdash;It will sometimes occur that on account of a curve
-or other obstacle, the arms and back lights of a distant or other
-signal cannot be seen from the signal cabin, and it is necessary to
-introduce an electric repeater. This little instrument consists of a
-miniature semaphore signal fixed in a metallic box with a glass front,
-and placed on a stand about a foot above the floor level immediately
-in front of the signal lever for which it is intended to serve as an
-indicator. Like the signal proper, the normal position of the
-miniature semaphore is at <em>danger</em>, but when the signal lever is
-pulled over in the cabin, the rod that pulls down the arm on the
-signal post effects a contact with an electric circuit which lowers
-the arm of the miniature semaphore at the same moment that the signal
-arm proper is lowered, and gives visible indication in the cabin that
-the signal is working. <a href="#fig500">Fig. 508</a> is a sketch of one form of electric
-repeater.</p>
-
-<p class="p2"><strong>Detonators</strong> or fog signals are largely used in foggy weather and
-snowstorms, when the out-door signals cannot be seen from an
-approaching train. At such times the atmosphere is so dense, and the
-surrounding objects so obscured, that an engine-driver is totally
-unable to distinguish the usual landmarks which guide him on the
-approach to a station or semaphore, and he might easily pass by a
-signal unless he received an audible signal to indicate the position
-of the one that is invisible. Detonators are usually made in the form
-of a circular tin or metallic case about two inches in diameter, and
-three eighths of an inch thick, with soft metal clips on opposite
-sides for bending over and securing to the rails. The case is filled
-with detonating powder, which is crushed by the first wheel passing
-over it, and explodes with a loud report. It is customary to use these
-detonators in pairs placed a short distance apart in case one of them
-should fail to explode.</p>
-
-<p>Fog-signalling regulations vary on different railways, but
-<!--347.png--><a name="Page_335" id="Page_335"></a><span class="pagenum">[Pg 335]</span>
-the
-arrangements are generally carried out somewhat in the following
-manner. During the prevalence of a fog or snowstorm, a fog <a name="signal">signalman</a>
-is placed near each of the signal-posts to be protected, and is
-supplied with a hand signal-lamp, hand-flags, and a packet of
-detonators. So long as the arm of the signal-post at which he is
-alongside stands at <em>danger</em>, he must keep two detonators on the rail
-of that line which the signal controls, and also show a <span class="muchsmaller">RED</span>
-hand-signal (hand-flag by day, and hand-lamp after dark) to the
-approaching train. When the signal arm is lowered to show that the
-line is clear for the passage of the train, the fog signalman must
-remove the two detonators, and show a <span class="muchsmaller">GREEN</span> hand-signal (flag, or
-lamp) to the approaching train. When an engine driver hears the report
-of a detonator crushed by his engine, it is his duty to shut off steam
-immediately, and bring his engine to a stand, after which he must
-proceed very cautiously, until he receives further signals by hand or
-otherwise, or receives the line-clear signal to continue on his
-journey. Detonators are also of great service both in fine or bad
-weather, in cases of a wash away, a failure of works, or obstruction
-on the line, when a hand-signal may not be seen, but a detonator must
-be heard.</p>
-
-<p class="p2"><strong>Mechanical Gates.</strong>&mdash;Mechanical gates, worked and controlled from the
-inside of a signal-cabin, are now very largely adopted for public road
-level-crossings instead of ordinary hand-gates, opened and closed by a
-gateman walking from side to side of the line across the rails. Being
-worked from inside the cabin, they remove all possibility of the
-gateman being struck by a passing train; they move simultaneously, and
-can be opened or closed in very much less time than hand-worked gates,
-which have to be moved one by one, and being interlocked with the
-signals, the mechanical gates cannot be placed across the lines of
-rails until the train-signals in each direction are set at
-<em>danger</em>. When set for either train traffic or public road traffic,
-the gates are held firmly in position by metal stops, rising out of
-cast-iron boxes lying flush with the ground, and worked by a separate
-lever in the signal-cabin.</p>
-
-<p>Assuming the gates to be set for train traffic, and it is desired to
-open them for the public road traffic, the first operation will be to
-pull over the levers, and raise the signals in each direction to
-<em>danger</em>, and thus release the stop-lever, which can then be pulled
-over, to lower the gate-stops and allow the gate-winch to be turned,
-and the gates moved round into correct
-<!--348.png--><a name="Page_336" id="Page_336"></a><span class="pagenum">[Pg 336]</span>
-position. The stop-lever must
-then be set back to raise the stops and hold the gates secure. The
-train-signals will be retained at <em>danger</em> by the interlocking
-gearing, and cannot be lowered until the gates are set back again
-across the public road, and the gate-stops raised.</p>
-
-<p>It is frequently urged that the celerity with which mechanical gates
-can be swung round and closed across the public road, is in itself a
-source of danger, and that persons preparing to cross the line might
-be struck by a moving gate, unless they received a distinct warning
-that such closing was about to take place. There is no doubt persons
-have been struck by such gates when closing across the road, and heavy
-claims for injuries have been decreed against railway companies, who
-were unable to prove that the man in charge had called out or given
-warning before moving the gates. To ensure that due and undeniable
-warning shall always be given, a firm of signal-makers have patented
-an appliance by which a powerful electric gong, fixed on the top of a
-tall post close to the gates, is sounded automatically by the gate
-machinery itself, and before the gates actually commence to move. As
-previously described, the pulling over of the lever to lower the
-gate-stops is the first operation to be performed whenever it is
-necessary to change the position of the gates, and it is the pulling
-over of this lever which actuates the apparatus, by bringing two
-electric points into contact, and thus starting the ringing of the
-gong or alarm. The gong continues to sound until the gates are moved
-over, the gate-stops raised, and the stop-lever put forward again into
-its normal position. The arrangement is very simple and very
-effective, and being purely automatic must work as regularly as the
-stop-lever. The tone and volume of the gong can be varied to suit
-circumstances. The public soon become familiar with its sound, and
-recognize its meaning.</p>
-
-<div class="figcenter">
- <a name="fig509"></a>
- <img src="images/i337.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 509 and 510"
- title="Figures 509 and 510"
- />
-</div>
-
-<p><a href="#fig509">Figs. 509 and 510</a> give sketch plan and elevation of a set of
-mechanical gates for a public road level crossing on a double line of
-railway. The signal-cabin should be placed within a few yards of the
-gates, to enable the man in charge to have a good view of the persons
-and vehicles passing over the roadway. The underground gearing for
-working the gates and stops, must be protected by iron or wooden
-casing. The swinging portion of the wicket gates is closed, and held
-by a separate lever. The gates shown on the sketch are for a crossing
-on the square, but
-<!--349.png--><!--350.png--><a name="Page_338" id="Page_338"></a><span class="pagenum">[Pg 338]</span>
-they can be equally well arranged for an oblique
-crossing, and of widths to suit the locality.</p>
-
-<p class="p2"><strong>Block-Telegraph Signalling.</strong>&mdash;However complete the outdoor signals and
-interlocking at any station, they can only control the movement of
-trains within their range, and something more is requisite to ensure
-the safe working of the traffic over the long lengths of line between
-stations. For some years a time-interval was allowed for the working
-of trains following one another on the <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> lines of a
-double line railway, no train being allowed to leave a station sooner
-than a fixed number of minutes after a previous train had started in
-the same direction. With this system there was always the risk that
-the first train might be overtaken and ran into by the second, and
-especially in the night time, or when the atmosphere was at all foggy.
-The electric telegraph was then called in to assist in the
-train-working, and brief telegrams were passed between the stations
-announcing the departure and arrival of trains. The increased security
-and convenience thus obtained led to the introduction of special
-electric telegraph instruments, devoted to the exclusive duty of
-train-working. These instruments, termed block telegraph instruments,
-are now almost universally used on all double lines of railway, and
-have largely contributed to the safe and efficient working of an ever
-increasing traffic. They are made in various forms, but the object of
-each is to ensure that before any train is allowed to start from, or
-pass any station, the signalman at that station shall receive from the
-signalman in the cabin in advance a distinct visible signal that the
-line is clear, and free of any train up to the cabin in advance; and
-also that after the train has been despatched, the signalman in the
-rear shall be at once advised when the train has arrived at the
-signal-cabin in advance. <a href="#fig511">Fig. 511</a> is a sketch of one type of
-block-telegraph instrument, in which the leading feature is the
-miniature signal-post with its two arms, an arrangement which readily
-appeals to the eye of the signalman as being so similar in form and
-action to the fixed signals in the station. Each instrument is
-supplied with a bell or gong, by which the adjacent signalmen can
-communicate with each other, in accordance with a fixed code of
-signals which defines the relative numbers of strokes of the bell or
-gong, to represent certain regulation calls and answers. In the
-signal-cabins of the intermediate stations, two
-<!--351.png--><a name="Page_339" id="Page_339"></a><span class="pagenum">[Pg 339]</span>
-block-telegraph
-instruments are required, one for the section of the line to the left
-hand of the cabin, and the other for the section to the right. At the
-terminal stations only one instrument is required.</p>
-
-<p>In the instrument shown in <a href="#fig511">Fig. 511</a>, the upper arm of the miniature
-signal-post is coloured <span class="muchsmaller">RED</span>, and is moved by electricity through the
-medium of the block telegraph instrument in the signal-cabin in
-advance; and until this <span class="muchsmaller">RED</span> signal be lowered to the <em>line clear</em>
-position by the signalman in the cabin in advance, no train must be
-allowed to start from or pass the cabin in the rear. The lower
-signal-arm coloured <span class="muchsmaller">WHITE</span> is lowered by the plunger <strong>A</strong> on its own
-instrument by the signalman in charge, and at the same moment lowers
-by electricity the upper or <span class="muchsmaller">RED</span> arm of the block-telegraph
-instrument in the signal-cabin at the other end of the section. The lower or
-<span class="muchsmaller">WHITE</span> arm is thus restricted to the signals sent away from the
-signal-cabin, while the upper or <span class="muchsmaller">RED</span> arm is restricted to signals
-received in the signal-cabin. In the centre there is a round handle <strong>B</strong>,
-which rotates a circular disc inside the instrument, and on this disc
-are painted three distinct train inscriptions, only one of which can
-be seen at a time through the glazed opening. One inscription has the
-words <span class="muchsmaller">ALL CLEAR</span> painted in black letters on a <span class="muchsmaller">WHITE</span> ground;
-another has the words <span class="muchsmaller">TRAIN ON LINE</span> painted in white letters
-on a <span class="muchsmaller">RED</span> ground; and the third has the words <span class="muchsmaller">TRAIN OFF, BUT SECTION
-BLOCKED</span> painted in black letters on a <span class="muchsmaller">GREEN</span> ground. The instrument is
-considered to be in its <em>normal</em> position when the <span class="muchsmaller">GREEN</span> inscription
-is in view, and both the miniature signal-arms raised to <em>danger</em>.</p>
-
-<p><a href="#fig511">Fig. 512</a> represents a portion of double line divided out into sections,
-or working blocks, between the stations <strong>B</strong>, <strong>C</strong>, and <strong>D</strong>. Each station is
-provided with the necessary block-telegraph instruments, and the usual
-distant, home, and starting semaphore signals.</p>
-
-<div class="figcenter">
- <a name="fig511"></a>
- <img src="images/i340.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 511 through 513"
- title="Figures 511 through 513"
- />
-</div>
-
-<p><a href="#fig511">Fig. 513</a> is a diagram sketch showing the pair of instruments as they
-stand on the instrument-tables in the signal-cabins <strong>B</strong> and <strong>C</strong>, where
-<strong>B<sup>2</sup></strong> and <strong>C<sup>1</sup></strong> are the instruments which work together for the block
-section <strong>BC</strong>. Supposing a <span class="muchsmaller">DOWN</span> train proceeding from <strong>A</strong> in
-the direction of <strong>F</strong>, and approaching the signal-cabin of the block station
-at <strong>B</strong>, the <span class="muchsmaller">DOWN</span> starting signal standing at <em>danger</em>; then by the code
-of signals on the bell or gong the signalman at cabin <strong>B</strong> would
-communicate with the signalman
-<!--352.png--><!--353.png--><a name="Page_341" id="Page_341"></a><span class="pagenum">[Pg 341]</span>
-at cabin <strong>C</strong>, to obtain <em>line clear</em>, so
-as to allow the approaching train to proceed on to <strong>C</strong>. If the previous
-train in the same direction had already passed <strong>C</strong>, and there was not
-any obstruction on the line, the signalman at <strong>C</strong> would give <em>line
-clear</em> for the <span class="muchsmaller">DOWN</span> train, and to do so he would turn his circular
-disc to show the <span class="muchsmaller">WHITE</span> inscription <span class="muchsmaller">ALL CLEAR</span>, and then push in the plunger
-of his <strong>C<sup>1</sup></strong> instrument, lowering the <span class="muchsmaller">DOWN</span> or white arm, <strong>K</strong>, of his own
-instrument to the position shown by the dotted lines, which operation would at the same moment
-lower by electricity the <span class="muchsmaller">DOWN</span> or red arm, <strong>G</strong>, of the instrument <strong>B<sup>2</sup></strong> in
-cabin <strong>B</strong> to the position of the dotted lines. The signalman at <strong>B</strong> would
-then lower his starting signal, to allow the <span class="muchsmaller">DOWN</span> train to proceed
-on towards <strong>C</strong>, and immediately the train had passed the starting signal
-he would, by means of his bell or gong advise the signalman at <strong>C</strong> that
-the train had entered the section, or block <strong>BC</strong>, and the signalman at
-<strong>C</strong> would at once turn his circular disc to show the <span class="muchsmaller">RED</span> inscription
-<span class="muchsmaller">TRAIN ON LINE</span>, and use his plunger to raise to <em>danger</em> the <span class="muchsmaller">DOWN</span> or
-white arm, <strong>K</strong>, of his own instrument, and at the same time raise by
-electricity the <span class="muchsmaller">DOWN</span> or red arm, <strong>G</strong>, to danger in the instrument
-<strong>B<sup>2</sup></strong> in cabin <strong>B</strong>. The section <strong>BC</strong> would then remain blocked until
-the <span class="muchsmaller">DOWN</span> train had arrived, or passed the station <strong>C</strong>, when the
-signalman there would, by means of his bell or gong advise the
-signalman at <strong>B</strong> that the <span class="muchsmaller">DOWN</span> train had passed out of the section,
-and would turn his circular disc to show the <span class="muchsmaller">GREEN</span> inscription <span class="muchsmaller">TRAIN
-OFF, BUT SECTION BLOCKED</span>. Both instruments would then be in their <em>normal</em>
-positions, with the arms raised to danger, and ready for further train
-operations. In a similar manner for the <span class="muchsmaller">UP</span>-line trains on the
-section or block between <strong>C</strong> and <strong>B</strong>, the signalman in <strong>B</strong>
-cabin would turn his circular disc, and use his plunger to lower the
-<span class="muchsmaller">UP</span> or white arm, <strong>H</strong>, in his own instrument, <strong>B<sup>2</sup></strong>, and at the same
-moment lower by electricity the <span class="muchsmaller">UP</span> or red arm, <strong>I</strong>, of the instrument
-<strong>C<sup>1</sup></strong> in cabin <strong>C</strong>, the other operation for train on line and train off
-being carried out for the <span class="muchsmaller">UP</span> train in the same routine as for the
-<span class="muchsmaller">DOWN</span> train. The outdoor fixed signals, or distant home and starting
-semaphore signals, have all to be worked to correspond to the block
-telegraph signals, and as the latter are always received well in
-advance of an approaching train, it follows that when the line is
-clear, the outdoor signals can be lowered so as to allow a through or
-non-stopping train to pass a block-telegraph station at full speed.</p>
-
-<p><!--354.png--><a name="Page_342" id="Page_342"></a><span class="pagenum">[Pg 342]</span>
-Where the traffic is moderate, it may be sufficient to have
-block-telegraph instruments at each of the stations, but with a very
-frequent train service it will be found necessary to divide the line
-into shorter sections, and erect signal-cabins and block-telegraph
-instruments at intermediate points between stations.</p>
-
-<p>The code of bell or gong signals is extended to include various
-matters in connection with the train-working. For example, when a
-<span class="muchsmaller">DOWN</span> train is passing cabin <strong>B</strong> at full speed, the signalman may
-observe that there is something wrong&mdash;a carriage or waggon on fire, a
-tail-lamp missing, or other irregularity. It is too late to stop the
-train with his own signals, but by means of his bell or gong he can
-call upon the signalman in cabin <strong>C</strong> to stop and examine the train, and
-the <span class="muchsmaller">DOWN</span> distant and home signals at <strong>C</strong> can be raised to
-<em>danger</em> before the train reaches the cabin at <strong>C</strong>.</p>
-
-<p>In every block-telegraph signal-cabin there is a train-book in which
-the signalman has to write down the time and description of every
-arriving or passing train, and, as this book lies before him, he has a
-complete record of the train-working, with the particulars of the
-exact times when the <em>line clear</em> signals were given, and also when
-the train arrived or passed his signal-cabin.</p>
-
-<p>To guard against the possibility of a signalman inadvertently giving
-<em>line clear</em>, or allowing another train to pass his cabin before the
-previous train had reached the signal-cabin in advance, some railways
-have adopted the lock and block system. By this arrangement the
-starting signal at any cabin is electrically and mechanically locked
-from the cabin in advance, and can only be released or lowered by the
-action of the outgoing train itself when passing over a treadle or
-other appliance connected with the rails of the running-line at the
-signal-cabin in advance. This method practically gives the train the
-complete control of the section; and any signalman attempting, in
-error, to lower his starting signal would find it to remain fixed to
-<em>danger</em> and immovable, until released by the arrival of the
-train at the advance cabin.</p>
-
-<p class="p2"><strong>Train-staff for Single Line.</strong>&mdash;When there is only a single line of
-railway for both an <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> train-service, very definite
-precautions must be adopted to prevent the meeting or collision of
-trains travelling in opposite directions. Where the piece of
-<!--355.png--><a name="Page_343" id="Page_343"></a><span class="pagenum">[Pg 343]</span>
-single
-line is short, and can be worked by one engine in steam, or two
-coupled together, no collision can take place, as the train-service
-will be limited to the one train moving backwards and forwards over
-the section; but with a long length of single line, including a large
-number of stations, necessitating several trains, some clear and
-comprehensive regulations must be introduced. For a long time the
-simple train-staff was found to give the desired security; there was
-only one staff for each pair of adjoining staff-stations, and no train
-was authorized to run without the staff, and as the staff could only
-be on one train at a time, the precaution against collisions was
-looked upon as complete. These staffs, which were generally made of
-brass, or other metal, were sufficiently large to be conspicuous when
-placed in the stand prepared for them on the engine. They were
-lettered to correspond to the stations to which they belonged, and
-were made in different patterns to distinguish them for their
-respective sections. No train was allowed to start from a station
-until the engine-driver received from the station-master the proper
-staff to authorize him to proceed to the next station, and on his
-arrival there it was the duty of the engine-driver to hand over the
-train-staff to the stationmaster of that place, and wait for another
-train-staff to authorize him to proceed over the next section. So long
-as the train service could be evenly arranged, and that there was
-always an <span class="muchsmaller">UP</span> train to take back a train-staff which has been carried
-out by a <span class="muchsmaller">DOWN</span> train, the simple staff worked most efficiently; but
-as the traffic increased, and two or more trains had to be despatched in the
-<span class="muchsmaller">DOWN</span> direction before one had to run in the <span class="muchsmaller">UP</span> direction,
-some auxiliary arrangement had to be introduced. This was effected by
-issuing train tickets, kept in a locked-up box, which could only be
-opened by the key attached to the train-staff. A properly dated
-train-ticket was handed to the engine-driver of the first
-<span class="muchsmaller">DOWN</span> train, and, if necessary, a second train-ticket to the
-engine-driver of a second <span class="muchsmaller">DOWN</span> train, and then the train-staff
-itself was handed to the engine-driver of the third <span class="muchsmaller">DOWN</span> train.
-There were one or two serious drawbacks to this train-staff and
-ticket-working. As there was only a time interval between the starting
-of the trains, the one train might overtake and run into the other
-with disastrous results. Again, a second or third train, which was put
-down in the schedule, might be withdrawn at the last moment, and the
-staff left behind at a station when it
-<!--356.png--><a name="Page_344" id="Page_344"></a><span class="pagenum">[Pg 344]</span>
-was required at the opposite end of
-the section, thus causing much confusion and delay. The ordinary
-electric telegraph could have been utilized to assist in regulating
-these train movements, but it was felt that a mere telegraph message
-was not sufficient to ensure positive safety, and that something more
-tangible was required in the shape of a staff, or token, without which
-no train should be allowed to travel on a single line of railway. To
-meet this requirement, the electric train-tablet, and the electric
-train-staff instruments have been invented, each of them being so
-arranged that upon any one section, or pair of instruments, a tablet
-or train-staff may be taken out from the instrument at either end of
-the section, but when once taken out, no other tablet or train-staff
-can be withdrawn from either instrument until the first has been
-delivered and placed again in one or other of the two instruments.</p>
-
-<p><a href="#fig514">Figs. 514, 515, and 516</a> are sketches of an electric train-staff
-instrument which has been very largely adopted on single lines, both
-at home and abroad.</p>
-
-<p>In a similar manner to the block-telegraph instruments for double
-line, the electric train-staff instruments have each a bell or gong by
-which the adjacent signalmen can communicate their calls and answers
-in accordance with a regulation code. In the signal-cabins of the
-intermediate stations two instruments are required, one for the staffs
-belonging to the section to the left of the cabin, and the other for
-the staffs of the section to the right. At a terminal station only one
-instrument is required.</p>
-
-<div class="figcenter">
- <a name="fig514"></a>
- <img src="images/i345.jpg"
- width="auto" height="100%"
- alt="Illustration: Figures 514 through 517"
- title="Figures 514 through 517"
- />
-</div>
-
-<p>The head of the instrument contains the electrical and mechanical
-locking apparatus which controls the withdrawal of a train-staff, or
-is acted upon by its insertion. The circular name-plates and pointers,
-together with the galvanometer in the centre, serve as indicators to
-guide the signalmen in carrying out the various operations. The staffs
-usually consist of thin steel tubes, solid at the ends, with metal
-rings fixed upon them, as shown in the sketch, the number and position
-of the rings varying according to the section or pair of staff
-stations to which they belong; this difference in the rings
-effectually preventing the possibility of one set of staffs being used
-or inserted in either of the instruments of the adjoining sections.
-The staffs rest normally in the long vertical slot <strong>A</strong>, with the rings
-fitting in vertical grooves, which prevent the removal of any staff
-except by passing it along the curved slot <strong>BC</strong>, and out by the
-<!--357.png--><!--358.png--><a name="Page_346" id="Page_346"></a><span class="pagenum">[Pg 346]</span>
-opening
-<strong>D</strong>, of large diameter. The electrical and mechanical locking apparatus
-is placed at the curved slot, and until the locking-bolt, which stands
-across the passage of the curved slot, be lifted by the joint
-operations of the signalmen and their instruments at both ends of the
-section, no staff can be withdrawn. When the instruments are standing
-in their <em>normal</em> position of “staffs in,” the signalmen can arrange
-between them to withdraw a staff&mdash;say either from the <span class="muchsmaller">NORTH</span> cabin
-instrument or from the <span class="muchsmaller">SOUTH</span> cabin instrument of the section, but
-only from one of them; and the act of taking out that staff
-automatically locks both instruments, and prevents the possibility of
-taking out any other staff from either instrument until the staff
-already removed is restored and inserted in one or other of the
-instruments. From the above description it will be seen that the
-electric train-staff instrument provides for the safe working of two
-or more trains proceeding, one at a time, in the same direction over a
-section of single line, each one being supplied with a train-staff,
-which must be handed over at the end of a section before another staff
-can be issued for a following train. Should the train-staffs
-accumulate in one instrument, in consequence of more trains running in
-one direction than another, a re-distribution of staffs is effected by
-the authorized persons according to fixed regulations.</p>
-
-<p>In the diagram sketch, <a href="#fig514">Fig. 517</a>, a piece of single line is shown
-divided into sections or blocks, with loops or passing-places at the
-stations. At the station <strong>E</strong> a train-staff taken out of the instrument
-<strong>F</strong> serves for the section up to the instrument <strong>L</strong> at the station <strong>H</strong>; and
-on the train-staff is a key which will open the detached locks on the
-points of the small intermediate station, <strong>G</strong>, as described in <a href="#fig500">Fig. 507</a>,
-in connection with the working of detached locks. At the station <strong>H</strong> the
-engine-driver receives another staff from the instrument <strong>M</strong>, which
-takes him to the instrument <strong>N</strong> at station <strong>K</strong>, and in like manner
-on this staff is a key which will open the detached lock on the
-colliery siding points at <strong>I</strong>. At stations <strong>H</strong> and <strong>K</strong> are shown loops, or
-short pieces of double line, with platform to enable an <span class="muchsmaller">UP</span> train to
-cross or pass a <span class="muchsmaller">DOWN</span> train. The distance apart of the electric
-train-staff stations will depend greatly upon the number of the
-trains, and for a frequent train-service it may be necessary to have
-the instruments at every station, whether large or small. The electric
-train-staff is of great advantage in the working of
-<!--359.png--><a name="Page_347" id="Page_347"></a><span class="pagenum">[Pg 347]</span>
-ballast or construction
-trains, as a staff may be taken out of the instrument <strong>F</strong> at station <strong>E</strong>,
-which will give possession of the section as far as station <strong>H</strong>, and
-when the ballasting operations&mdash;which may be very near to <strong>E</strong>&mdash;are
-completed, the train can return to <strong>E</strong>, and deliver the staff again to
-the instrument <strong>F</strong>, instead of having to run the entire distance to
-station <strong>H</strong>. Although carrying a train-staff, the engine-driver must
-approach stations cautiously, and obey the fixed signals in the usual
-manner.</p>
-</div><!--end chapter seven-->
-<div class="chapter">
-
-<!--360.png--><a name="Page_348" id="Page_348"></a><span class="pagenum">[Pg 348]</span>
-
-<p class="smaller"><a href="#top">[Contents]</a></p>
-<h3 class="p4">CHAPTER VIII.</h3>
-
-<p class="hanging smaller">Railways of different ranks&mdash;Progressive improvements&mdash;Growing
-tendency for increased speeds, with corresponding increase in weight
-of permanent way and rolling-stock&mdash;Electricity as a motive-power.</p>
-
-<p class="p2">Looking at railways in their present stage of development, they appear
-to be divided into three ranks, each one distinct from the other as
-regards its importance, capability, and prospects.</p>
-
-<p>In the first rank are the great trunk lines, which, at home or abroad,
-pass through thickly populated districts, rich in manufactures,
-minerals, or shipping industries, with their enormous movement of
-materials and people, and consequently requiring the most ample works,
-equipment, and appliances for security.</p>
-
-<p>In the second rank may be classed those railways which run through
-ranges of country where the population is moderate, or where the
-manufacturing industries are few in number and of minor importance.
-Although of the utmost value to the community of the long series of
-small towns and agricultural districts through which they pass, and
-forming the only great commercial highway, or connecting link, with
-some distant seaport, or leading business centre, the traffic returns
-upon such lines are too small to permit of the introduction of the
-more complete appliances and luxuries to be met with on the richer
-railways. In newly opened-out countries, and in distant colonies, such
-lines have often to struggle on for years against financial returns so
-small as to barely enable them to maintain a condition of efficiency;
-but where there are natural advantages in soil and climate, combined
-with a judicious development of all the available resources, the
-result will be the raising of the standard of the railway itself, and
-the enrichment of the entire district through which it passes. When
-laying out lines of this description, it may be necessary to curtail
-as much as possible the expenditure on works and equipment, but there
-should be no hesitation in obtaining liberal quantities of land for
-future
-<!--361.png--><a name="Page_349" id="Page_349"></a><span class="pagenum">[Pg 349]</span>
-enlargement of stations, or for constructing additional
-stations on promising sites. The value of the land may be small in the
-outset, but will be enhanced enormously as the benefits of the
-undertaking become appreciated.</p>
-
-<p>In the third rank may be grouped those branch lines which, starting
-from a main passenger or goods line, are laid down to some outlying
-town, seaport, or mining centre, which, although small, is considered
-of sufficient importance to be brought into railway communication. In
-general, these lines are laid to the same gauge as the line with which
-they connect, and the transfer of merchandise waggons is readily
-effected at the point of junction. Others, from motives of economy,
-have been laid down to a narrow gauge, involving the transhipment of
-all goods and cattle at the station where the break of gauge takes
-place. Most of these branch lines are laid out through the open
-country, like an ordinary standard railway, but with a minimum of
-works and appliances. Others are laid down partly on level public
-roads, and partly through the fields, and are in consequence subject
-to a statutory low rate of speed when travelling over those portions
-on the public roads.</p>
-
-<p>In many cases the construction of second and third rank railways, both
-at home and abroad, has been largely assisted by state or provincial
-aid. Such assistance must always be valuable to poor or undeveloped
-districts, but judgment should be exercised so as not to encourage the
-introduction of any scheme which would interfere or become competitive
-with any existing undertaking constructed by public enterprise. So
-long as capitalists invest their money more from commercial motives
-than from feelings of philanthropy, it would, to say the least, be
-unjust and impolitic for any country to adopt a course of competition
-by national funds, and so check the flow of public money into public
-undertakings. Ordinary public commercial competition may be business,
-as each party can value and compare their own prospects; but the
-competition of a scheme enjoying national aid and free money grants is
-very apt to become one-sided.</p>
-
-<p>There is every indication that even what may be termed a fourth-rank
-type of railway is destined to play a very important part in the
-industrial enterprises of many countries, and that in the form of
-little lines, made to any convenient gauge, and laid either along
-public roads or open country, or both, the produce from isolated
-manufactories, forests, quarries, and large farms will be
-<!--362.png--><a name="Page_350" id="Page_350"></a><span class="pagenum">[Pg 350]</span>
-conveyed to
-the nearest railway stations with greater facility and at much less
-expense than by carting along the public highway. Such little lines
-are available in places where the most sanguine promoter would
-hesitate to suggest an ordinary railway, and may be found to supply
-what is felt to be the missing link in the economical transport of a
-long list of materials of everyday use. As they would be almost
-exclusively intended for merchandise purposes, the statutory
-requirements would be on the most moderate scale, and as they would be
-generally constructed at the cost of the parties who had to operate
-them, the outlay would be restricted to the actual works necessary for
-convenience and efficiency. Similar little lines have been in use for
-many years in the busy yards of large ironworks, shipbuilders, and
-many other localities, where weighty masses of materials have to be
-moved from place to place in the course of manufacture, and it would
-be merely carrying out the same idea to a more extended range. The
-principal inducement for their introduction is the great advantage,
-both in convenience and cost, that is obtained by hauling a ton of
-materials over a pair of rails as compared with carting the same
-weight along an ordinary road; and as the fact becomes more and more
-proved by experience, these little fourth-rank lines will become more
-general. Numbers of them are in use at the present time, and some of
-them, even of only 2-feet gauge, are doing good service, the little
-trucks conveying manufactured goods to the nearest railway station and
-returning loaded with coals and other materials. By making suitable
-arrangements for passing places and junctions, the system could be
-carried out to considerable distances in thinly populated districts,
-and be made available by means of local sidings, to several places
-along the route. With a narrow-gauge type there would, of course,
-always be the time and expense of transhipment to or from the ordinary
-railway trucks in the same way as with the road carts, but the time
-and expense may be lessened by so constructing the little narrow-gauge
-trucks that the bodies may be readily lifted off the frames and
-wheels, and be placed like packing-cases in the railway waggons.</p>
-
-<p>It is natural to look to the railways of the first rank for the latest
-advances in construction, appliances, and equipment, and it is
-generally there they are found. Great trunk lines, crowded with
-traffic of all kinds, have not only the opportunity and means, but all
-the strong inducements to try or adopt any
-<!--363.png--><a name="Page_351" id="Page_351"></a><span class="pagenum">[Pg 351]</span>
-arrangement which promises
-greater facilities for dealing with the ever-increasing demands made
-on their carrying powers.</p>
-
-<p>Passenger and goods traffic are so dissimilar in their requirements
-that when both of them are steadily increasing it becomes difficult,
-if not impossible, to work the two classes over an ordinary double
-line. In some cases much assistance has been obtained by shortening
-the lengths of the working sections and introducing intermediate
-electric telegraph block stations between the ordinary stations. Long
-refuge-sidings have also been introduced at many of the signal-cabins
-or stations, into which goods trains can be shunted out of the way to
-allow fast passenger trains to pass through without stopping. Up to a
-certain extent this arrangement works fairly well, but where there is
-a very frequent service of fast and slow passenger trains, combined
-with a heavy and constant service of goods and mineral trains, the two
-lines of way are practically incapable of accommodating such a number
-of mixed trains without causing serious detentions. The goods trains
-must shunt out of the way some time before a passenger train is due,
-and this frequent shunting into sidings results in hours of delay in
-the transit of the goods and cattle traffic; and when one of such
-trains is allowed to proceed again on its way up to another station,
-dove-tailed as it may be between two fast passenger trains, there is
-always the tendency to run at a much higher rate of speed than is
-prudent for the class of rolling-stock of which the goods train is
-composed. To overcome this difficulty some railways have introduced
-additional <span class="muchsmaller">UP</span> and <span class="muchsmaller">DOWN</span> lines on the busiest part of their system,
-making four lines of way in all, two of these being reserved for the
-fast passenger and through trains, and the other two for slow trains,
-goods, and mineral trains. This arrangement of the four lines has
-afforded great relief to the traffic of all kinds, and has enabled the
-service to be worked with much greater facility and punctuality. The
-goods trains being restricted to their own separate lines, can proceed
-regularly in their order, at their uniform working speed, without
-having to resort to the spasmodic fast running too often expected from
-them when passing over some parts of an ordinary double line.
-Doubtless this four-line system, or rather the principle of laying
-down two additional lines of way, will go on extending, and will be
-accelerated in its accomplishment by the growing demand for still
-higher speed of our fast passenger trains, and still longer distances
-to be traversed
-<!--364.png--><a name="Page_352" id="Page_352"></a><span class="pagenum">[Pg 352]</span>
-without stopping. High-speed long-distance through
-trains can only perform their journeys with punctuality, when the
-route is kept clear of all other trains or obstructions which might
-interfere with their free running. Any check or stoppage in their
-course would cause loss of time and prestige.</p>
-
-<p>It is to be regretted that in so many of the cases where two
-additional lines of way have been laid down, more space was not left
-between the sets of rails for the fast traffic and those for the slow.
-In many instances the dividing space is not more than 7 or 8 feet. It
-would have been better and safer if it could have been made 20 feet.
-An ordinary goods train is made up of several kinds of trucks, some
-empty, some loaded, many of them unequally loaded, all of them subject
-to heavy work and rough handling, and more likely to give trouble than
-the higher class vehicle, the passenger carriage. The breaking down or
-derailment of one or two goods trucks on a line of rails close
-alongside the fast passenger rails, would in all probability so foul
-and obstruct the passenger line as to cause a very serious accident to
-an express train which could not be stopped in time. The greater width
-would not only provide more clearance in case of breakdowns, but would
-afford increased safety to the platelayers and other workmen engaged
-on the line. The permanent-way men have to be very watchful to keep
-out of danger on an ordinary busy double line, but they must be very
-much more on the alert where there are four lines of way close
-together side by side.</p>
-
-<p>In the neighbourhood of large cities and important manufacturing
-centres, railways have created a distinct traffic for themselves by
-providing means for a large portion of the population to reside in
-convenient suburbs. Local trains running at suitable business hours
-have induced people of all classes to select homes a few miles away
-from town, and the gradual growth of this suburban traffic has
-produced its own advantages and requirements. At the large terminal
-stations platform after platform has been added to accommodate the
-increased number of trains which arrive in the busy parts of the
-morning or depart in the evening. Every facility has to be provided to
-permit of the expeditious ingress and egress of the large crowds
-forming the respective trains&mdash;ample platforms, over-line
-foot-bridges, subways, convenient booking-offices, waiting-rooms, and
-left-luggage rooms.</p>
-
-<p><!--365.png--><a name="Page_353" id="Page_353"></a><span class="pagenum">[Pg 353]</span>
-The enormous train service on some of these first-rank lines demands
-the highest efficiency in the signalling and interlocking
-arrangements, and the use of any devices which will ensure increased
-facility and safety in the working of the traffic. With a crowd of
-trains passing a signal-cabin in both directions, and often over four
-lines of way, it is quite possible for a signalman to make a mistake
-which cannot be rectified in time to prevent an accident. To obtain
-increased security many railways have adopted the lock and block
-system previously described, or some adaptation of the same principle,
-and this method of working will go on extending as the traffic
-increases. These additional appliances entail additional care and
-inspection, for although automatical machinery may be exempt from the
-human frailty of preoccupation of mind or forgetfulness, it is
-somewhat delicate in its organization, and requires constant
-supervision to maintain its efficiency.</p>
-
-<p>On many of the large lines, much has been done to give improved
-carriage accommodation. Carriages have been made longer, easier on the
-road, loftier, better furnished, and better lighted; but there is
-still a very great deficiency in those conveniences so essentially
-necessary, especially on trains running long distances without
-stopping. Drawing-room cars and dining-room cars are no doubt
-attractive, and may contribute considerably to the popularity of
-certain routes; but it is questionable whether many of the lines at
-home and abroad which have adopted such luxuries, have not in doing so
-commenced at the wrong end, and whether it would not have been more to
-the public satisfaction to have begun by first providing those
-conveniences which are found in every carriage on every line in the
-United States. It is satisfactory to find that there is a steadily
-growing tendency to so construct passenger carriages that their
-occupants may, by passages or corridors, communicate with all parts of
-the same carriage or with the adjoining carriages; and there is every
-reason to assume that the carriage of the future, either by
-legislation or consent, will combine both the items of conveniences
-and intercommunication, and will confer not only greater comfort to
-the passengers, but also increased protection against those outrages
-which, unfortunately, too frequently occur under the system of
-isolated compartments.</p>
-
-<p>It will be instructive to watch the results of the passenger
-<!--366.png--><a name="Page_354" id="Page_354"></a><span class="pagenum">[Pg 354]</span>
-receipts
-on those lines where only first and third-class carriages are used.
-The elimination of the second class may at first sight appear an
-innovation; but if there is not any pecuniary loss sustained, there
-must be a gain in the reduction of unoccupied seats to be hauled. It
-is customary to provide in every train a liberal number of spare seats
-of each class to meet contingencies; and the omission of one class may
-mean the saving of two or three carriages&mdash;a very important item in
-locomotive power.</p>
-
-<p>On important through lines high-speed running has become a leading
-feature, and compels a very efficient standard of perfection in works
-and rolling-stock to effect its attainment. There is no indication of
-remaining contented with what has been already accomplished; on the
-contrary, the spirit of restlessness is always urging to do something
-more. The travelling public speak as calmly now of a speed of seventy
-miles an hour as they did of thirty-five a few years ago; they
-thoroughly recognize the value of railways, and they merely desire to
-travel still faster. The incentives of emulation and competition are
-ever present to encourage further and further reduction of the running
-time, and the railway that offers a special fast through service for
-some of its passenger and mail trains, reasonably expects its
-popularity and patronage to be in the ascendant. Much has been done in
-permanent way and equipment to make the present high speeds possible,
-but more will be required if the speeds are to go on increasing. The
-passenger carriages for such work must be very substantial, and
-naturally heavy. The locomotives to haul a long train must have
-increased power and weight, and will necessitate stronger rails to
-carry the greater rolling loads. With the present system of
-motive-power, the heaviest item is the locomotive, and its weight must
-always determine and regulate the character of the works and permanent
-way. Rails weighing 90 pounds per yard are becoming common, and there
-is clear indication that before very long sections weighing from 100
-to 120 pounds, or more, per yard will be brought into use on many
-lines. There will be no difficulty in making a permanent way strong
-enough for rolling loads very far in excess of anything in the present
-practice; but it will be costly, and the extra expense per mile,
-extended over a few hundred miles, will represent a sum so large as to
-raise the question in many cases whether the probable advantages and
-additional remuneration to be obtained will warrant the outlay.</p>
-
-<p><!--367.png--><a name="Page_355" id="Page_355"></a><span class="pagenum">[Pg 355]</span>
-To some extent the increased speed may be attained by dividing the
-present long trains into two shorter trains, with a fair interval of
-time between them. There are many splendid locomotives now running,
-which on a fairly level line can reach a speed of considerably over
-seventy miles an hour with a short train, but would be quite incapable
-of doing so with a long train. At the same time it is possible that if
-passengers increase in the same proportion as the inducements
-provided, the short train might not be sufficient for the numbers
-presented, and there would be no other alternative but to resort to
-still greater rolling loads and stronger hauling power.</p>
-
-<p>Perhaps electricity, which has already achieved so many marvels, is
-destined to take a still more prominent part as a motive-power in the
-working of ordinary railways, and may help out of the difficulty by
-inaugurating still higher speeds without the necessity of incurring
-stronger works or heavier permanent way. In addition to its success in
-the telegraph, in the telephone, and in its brilliant light,
-electricity is every day coming more and more to the front as a
-motive-power. At present many tramways and short lines, some of them
-in tunnel, some above ground, and many of them with very steep
-gradients, are successfully worked by electricity; but these, being of
-modern construction, were specially designed and equipped for that
-method of working, and none of them as yet resort to high speeds. Such
-rapid strides have, however, been already made in the progress of this
-system of haulage, as to promise that both increased power and speed
-will be forthcoming when the demand for them is made manifest. Various
-modes of application are being tried: overhead wires, underground
-wires, conductors on the level with the rails, storage batteries or
-accumulators, and self-contained electric motors, each and all of them
-being carefully tested to ascertain the comparative cost and
-efficiency. Much will depend upon the localities and advantages to be
-obtained for the respective generating stations. In places where a
-large, constant, and unutilized water supply is available, a great
-saving may be effected in the most expensive item of electric working,
-but in the greater number of cases steam-power will have to be adopted
-for driving the generating machinery. The main question will be
-whether electricity in its most approved form of application can haul
-a ton of paying load for one mile at a less average cost, and at as
-great or greater speed
-<!--368.png--><a name="Page_356" id="Page_356"></a><span class="pagenum">[Pg 356]</span>
-than the ordinary locomotive. Until there is
-very clear evidence that electricity is cheaper, there will not be any
-great inducement for its general use as a motive-power on ordinary
-railways.</p>
-
-<p>Experiments have been made on some existing railways to ascertain how
-far this new motive-power can be made serviceable under special
-circumstances. In one case, a powerful electric motor-car has been
-introduced for working frequent and heavy trains through a long
-tunnel, where the atmosphere with ordinary steam locomotives became
-foul almost to suffocation, and the result has shown that the traffic
-can be hauled efficiently by electricity, and the air in the tunnel
-maintained pure and clear. In this instance, the question of cost was
-of secondary importance, the primary object being to avoid the
-asphyxiating gases emitted from the ordinary locomotives.</p>
-
-<p>In other cases, specially designed electric motor-cars have been
-constructed with a view to obtain a higher speed for passenger trains
-than is at present attained with the locomotives, and the trials made
-have proved that these cars could reach a high speed, but so far only
-with limited loads. Experiments are still going on with larger and
-improved machines, from which it is expected to obtain both high speed
-and much increased hauling power.</p>
-
-<p>It is more than probable that amongst the earliest practical
-applications of electric motive-power on existing railways will be its
-introduction as an auxiliary on the steep gradients of some of the
-mountain railways abroad. In many of these regions there are millions
-of gallons of water running to waste down the ravines, a portion of
-which could be utilized in working powerful generating plant, to drive
-strong electric motor-cars for assisting the ordinary locomotives up
-the steep inclines. In such localities, with free water-power, the
-cost of the electricity would be at a minimum, while the cost of the
-ordinary locomotive would be at a maximum.</p>
-
-<p>In whatever form the electric motor-car may be designed, we are
-brought face to face with the old axiom, that there must be a certain
-amount of weight to obtain a certain amount of adhesion; but there
-will be one important point in favour of the motor-car, that whereas
-in the ordinary locomotive the weight for traction can only be
-distributed over a few working wheels, the electric arrangement may
-distribute it over a much greater number, and so diminish the
-insistent weight of each wheel upon
-<!--369.png--><a name="Page_357" id="Page_357"></a><span class="pagenum">[Pg 357]</span>
-the rails. There would also be the
-saving of the dead weight of the tender, the fuel, water, and other
-minor accessories, as well as the advantage that the active power
-would be applied in a rotary form instead of reciprocating.</p>
-
-<p>There are important interests at stake in the perfecting of this new
-system of haulage, and day by day new developments are being made to
-add to its efficiency and reduce its cost. Existing railways will,
-however, naturally require some very convincing proof of the all-round
-superiority of electricity before adopting that power generally in
-place of their present locomotives. The latter, with their
-corresponding workshops and appliances, represent so large an amount
-of invested capital, as to demand most thorough trials and
-investigation of the new power before they are superseded;
-nevertheless, if further experience proves that electrical power is
-better and cheaper than the ordinary steam locomotives, then the
-change will undoubtedly be made.</p>
-
-<p>Under whatever system of haulage the acceleration of trains be
-obtained, the increased speed will call for increased precautions in
-the selection and proving of the materials to be used in such service.
-Rails must be made more uniform in quality, and must be free from the
-imputation of fracture under regular wear. Notwithstanding the great
-improvements made in the preparation of the steel, and in the rolling,
-there are still far too many steel rails which break under traffic to
-allow rail-makers to rest satisfied with their work. Something is
-still wanting in the manufacture to effectually remove this
-disposition to fracture. The safe rail, the rail of the future, must
-be one that may bend and may wear, but will never break under ordinary
-use in the road. Axles must be stronger and tougher, as they will have
-to bear greater torsional strains than are now imposed upon them; and
-the wheels, of whatever type they are made, must be incapable of
-collapsing or falling to pieces upon the sudden and severe application
-of the brake-blocks. A train, rushing along at a speed of 70 or 80
-miles an hour, may on an emergency have to be brought to a stand in
-the shortest distance possible, and the failure of either axles or
-wheels in the endeavour to avert one form of accident would inevitably
-initiate another.</p>
-
-<p>To permit of unchecked high-speed running, many sharp curves will have
-to be flattened, bridges will have to be built at busy level
-crossings; and points, crossings, and junctions on the
-<!--370.png--><a name="Page_358" id="Page_358"></a><span class="pagenum">[Pg 358]</span>
-main lines will
-have to be reduced to the smallest possible number.</p>
-
-<p>It would be difficult to form an opinion as to how far passenger
-traffic will go on expanding, but if it continues to increase at the
-same rate as at present, some railways may find it expedient, and even
-absolutely necessary, to construct new lines altogether separate and
-apart from the existing routes, and for the sole use of their fast
-through traffic. As roadside or intermediate traffic would not form
-any part of the scheme, such lines could be laid out so as to keep
-away from the populous districts, where property would be costly, and
-pass instead through those parts of the open country where the most
-direct course and easiest gradients could be obtained. Stations would
-only be required at the very large and important places, and at long
-distances from each other. Lines of this description, reserved for
-through traffic only, taken alone, might not pay, but taken in
-conjunction with the existing lines, of which they would form a part,
-they might prove to be the best solution of the problem of dealing
-with a crowded train service, the remunerative earnings of which,
-placed together, might yield a rich return over the entire system. A
-project for a separate through line might at first appear a little
-startling, but we have well-known precedents in the vast expenditure
-already incurred in the constructing of enormous viaducts and
-connecting lines to avoid long detours on certain through routes. The
-widening out of an ordinary double line into a four-line road was at
-first considered as a rather venturesome departure; and it must always
-be costly because, in addition to the earthworks and permanent way,
-there is the doubling of all the over and under bridges and waterways,
-besides the great and expensive alterations at stations. Practically
-it is almost like making a second railway, and yet the constant
-extension of the principle is an admission that the working results
-have proved satisfactory, in spite of the large outlay. A little later
-the question will force itself more prominently into notice, whether
-the four-line track or the separate fast through traffic lines, will
-best answer the purpose. The former possesses certain advantages, but
-the latter would give more freedom for high-speed running.</p>
-
-<p>Engineers have brought railways to their present stage of perfection,
-and the public will expect them to devise and carry out still further
-improvements as the march of development
-<!--371.png--><a name="Page_359" id="Page_359"></a><span class="pagenum">[Pg 359]</span>
-moves onward. It is a simple
-matter to arrange the traffic on a railway when all the works and
-appliances are appropriate for the service to be performed; but the
-advances which are made follow one another so rapidly as to
-necessitate constant study and organization to effect the structural
-alterations and additions requisite to maintain an up-to-date standard
-of efficiency. The traffic manager on a railway receives his
-instructions from the directors or controllers of the company as to
-the working out of the train service, rates, charges, and other items
-of his department, but the engineer has to stand alone, and his
-technical knowledge and professional skill must enable him not only to
-design and construct works suitable in character, extent, and strength
-to the duty for which they are intended, but also to decide when
-structures are no longer capable of properly sustaining the increasing
-loads brought upon them, and must be taken down and replaced with
-others of a stronger description. For this reason the engineer must
-carefully consider every circumstance and local feature which may
-influence the design to be prepared; he must thoroughly investigate
-the nature of the ground for foundations, as the description when
-ascertained will frequently determine the class of work to be erected,
-whether in viaducts, bridges, or buildings; and in his selection of
-materials and calculations for strength, he must allow ample margin to
-meet further increased weights, as well as for natural deterioration.</p>
-
-<p>He should, indeed, go a little further, and as his perceptive ability
-and training will always enable him the more readily to foreshadow the
-direction in which improvements or changes are tending, he should
-study out and be prepared with his schemes to meet the new departures
-as the requirements gradually arise.</p>
-
-<p>Strength and efficiency are the leading points which must be always
-kept in view, and the engineer must never forget that he is solely
-responsible for the safety of the line and works, and of the public
-passing over the same.</p>
-</div><!--end chapter eight-->
-
-<div class="chapter">
-<p class="p4"><!--372.png--><!--373.png--><a name="Page_361" id="Page_361"></a><span class="pagenum">[Pg 361]</span></p>
-
-<h3>INDEX</h3>
-
-<ul class="IX none">
-<li class="indent">A</li>
-</ul>
-<ul class="IX none">
-  <li>Accommodation works,&nbsp;<a href="#Page_12">12</a></li>
-  <li>Air-lock,&nbsp;<a href="#Page_119">119</a></li>
-  <li>Air-pump,&nbsp;<a href="#Page_120">120</a></li>
-  <li>Allowances for sinkage on embankments,&nbsp;<a href="#Page_70">70</a></li>
-  <li>Alteration of gradients,&nbsp;<a href="#Page_12">12</a>
-     <ul class="IX none">
-     <li>of roads,&nbsp;<a href="#Page_6">6</a>, <a href="#Page_10">10</a></li>
-     </ul></li>
-  <li>American hand-brake,&nbsp;<a href="#Page_46">46</a></li>
-  <li>Analysis of steel rails,&nbsp;<a href="#Page_193">193</a></li>
-  <li>Approach roads to stations,&nbsp;<a href="#Page_249">249</a></li>
-  <li>Arch culverts,&nbsp;<a href="#Page_76">76</a></li>
-  <li>Automatical gate-alarm,&nbsp;<a href="#Page_336">336</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">B</li>
-</ul>
-<ul class="IX none">
-  <li>Ballast,&nbsp;<a href="#Page_225">225</a></li>
-  <li>Bascule bridge,&nbsp;<a href="#Page_85">85</a></li>
-  <li>Battering-rule,&nbsp;<a href="#Page_72">72</a></li>
-  <li>Bearing-weights of various materials,&nbsp;<a href="#Page_129">129</a></li>
-  <li>Beater,&nbsp;<a href="#Page_239">239</a></li>
-  <li>Bench marks,&nbsp;<a href="#Page_66">66</a></li>
-  <li>Bissell truck,&nbsp;<a href="#Page_58">58</a></li>
-  <li>Block crossing, cast steel,&nbsp;<a href="#Page_235">235</a>
-     <ul class="IX none">
-     <li>telegraph signalling,&nbsp;<a href="#Page_18">18</a>, <a href="#Page_338">338</a></li>
-     </ul></li>
-  <li>Board of Trade requirements,&nbsp;<a href="#Page_18">18</a></li>
-  <li>Bog-cutting,&nbsp;<a href="#Page_65">65</a></li>
-  <li>Bogie carriage,&nbsp;<a href="#Page_54">54</a>
-     <ul class="IX none">
-     <li>engine,&nbsp;<a href="#Page_56">56</a>, <a href="#Page_306">306</a></li>
-     </ul></li>
-  <li>Booking-hall,&nbsp;<a href="#Page_249">249</a>, <a href="#Page_260">260</a></li>
-  <li>Book of reference,&nbsp;<a href="#Page_8">8</a></li>
-  <li>Borings for foundations,&nbsp;<a href="#Page_129">129</a>
-     <ul class="IX none">
-     <li>for tunnel work,&nbsp;<a href="#Page_164">164</a></li>
-     </ul></li>
-  <li>Borrowed earthwork,&nbsp;<a href="#Page_61">61</a></li>
-  <li>Bottom-pitching,&nbsp;<a href="#Page_225">225</a></li>
-  <li>Bracket signals,&nbsp;<a href="#Page_20">20</a>, <a href="#Page_322">322</a></li>
-  <li>Brake-power on gradients,&nbsp;<a href="#Page_45">45</a></li>
-  <li>Brakes for goods waggons,&nbsp;<a href="#Page_46">46</a></li>
-  <li>Brick-well foundations,&nbsp;<a href="#Page_123">123</a></li>
-  <li>Bridges,&nbsp;<a href="#Page_79">79</a>
-     <ul class="IX none">
-     <li>over public roads,&nbsp;<a href="#Page_10">10</a></li>
-     </ul></li>
-  <li>Broken stone ballast,&nbsp;<a href="#Page_225">225</a></li>
-  <li>Buffer-stops,&nbsp;<a href="#Page_282">282</a></li>
-  <li>Bull-head rail,&nbsp;<a href="#Page_191">191</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">C</li>
-</ul>
-<ul class="IX none">
-  <li>Cab-rank,&nbsp;<a href="#Page_251">251</a></li>
-  <li>Caisson foundations,&nbsp;<a href="#Page_121">121</a></li>
-  <li>Cant of rail,&nbsp;<a href="#Page_230">230</a></li>
-  <li>Carriage accommodation,&nbsp;<a href="#Page_353">353</a>
-     <ul class="IX none">
-     <li>bogie,&nbsp;<a href="#Page_54">54</a></li>
-     <li>dock,&nbsp;<a href="#Page_282">282</a></li>
-     <li>traverser,&nbsp;<a href="#Page_292">292</a></li>
-     </ul></li>
-  <li>Cast-iron column piers,&nbsp;<a href="#Page_97">97</a>
-     <ul class="IX none">
-     <li>in bridges,&nbsp;<a href="#Page_27">27</a></li>
-     <li>saddles,&nbsp;<a href="#Page_224">224</a></li>
-     <li>sleepers,&nbsp;<a href="#Page_214">214</a></li>
-     <li>tram-plates,&nbsp;<a href="#Page_184">184</a></li>
-     <li>tube tunnels,&nbsp;<a href="#Page_179">179</a></li>
-     <li>water-tanks,&nbsp;<a href="#Page_299">299</a></li>
-     </ul></li>
-  <li>Catch-siding,&nbsp;<a href="#Page_26">26</a></li>
-  <li>Centre line of railway,&nbsp;<a href="#Page_32">32</a></li>
-  <li>Chairs,&nbsp;<a href="#Page_206">206</a></li>
-  <li>Channelling ballast,&nbsp;<a href="#Page_231">231</a></li>
-  <li>Check-rails on sharp curves,&nbsp;<a href="#Page_29">29</a>, <a href="#Page_51">51</a></li>
-  <li>Cinder ballast,&nbsp;<a href="#Page_227">227</a></li>
-  <li>Circular running-shed,&nbsp;<a href="#Page_289">289</a></li>
-  <li>Clay puddle,&nbsp;<a href="#Page_127">127</a></li>
-  <li>Clocks at stations,&nbsp;<a href="#Page_26">26</a></li>
-  <li>Coal-drops,&nbsp;<a href="#Page_282">282</a></li>
-  <li>Coffer-dams,&nbsp;<a href="#Page_127">127</a></li>
-  <li>Comparison of bull-head and flange rails,&nbsp;<a href="#Page_199">199</a></li>
-  <li>Compound rails,&nbsp;<a href="#Page_190">190</a></li>
-  <li>Concrete foundations,&nbsp;<a href="#Page_114">114</a></li>
-  <li>Continuous brakes,&nbsp;<a href="#Page_30">30</a></li>
-  <li>Cost of permanent way,&nbsp;<a href="#Page_241">241</a>, <a href="#Page_242">242</a>
-     <a name="Page_362" id="Page_362"></a><span class="pagenum">[Pg 362]</span></li>
-  <li>Covered-way tunnels,&nbsp;<a href="#Page_178">178</a></li>
-  <li>Crab bolts,&nbsp;<a href="#Page_223">223</a></li>
-  <li>Cranes,&nbsp;<a href="#Page_280">280</a>, <a href="#Page_294">294</a></li>
-  <li>Creosoted sleepers,&nbsp;<a href="#Page_211">211</a></li>
-  <li>Cross-over road,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Crossings made of rails,&nbsp;<a href="#Page_237">237</a></li>
-  <li>Cross-sections,&nbsp;<a href="#Page_33">33</a></li>
-  <li>Culverts and drains,&nbsp;<a href="#Page_74">74</a></li>
-  <li>Curve alterations,&nbsp;<a href="#Page_12">12</a></li>
-  <li>Curves,&nbsp;<a href="#Page_49">49</a></li>
-  <li>Cutting rails on curves,&nbsp;<a href="#Page_229">229</a></li>
-  <li>Cylinder foundations,&nbsp;<a href="#Page_116">116</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">D</li>
-</ul>
-<ul class="IX none">
-  <li>Datum line,&nbsp;<a href="#Page_8">8</a></li>
-  <li>Deck or floor of girder bridges,&nbsp;<a href="#Page_133">133</a></li>
-  <li>Deposited plans,&nbsp;<a href="#Page_4">4</a>, <a href="#Page_6">6</a></li>
-  <li>Depths of cuttings,&nbsp;<a href="#Page_10">10</a></li>
-  <li>Derrick crane,&nbsp;<a href="#Page_299">299</a></li>
-  <li>Detached lock,&nbsp;<a href="#Page_332">332</a></li>
-  <li>Detonator or fog signals,&nbsp;<a href="#Page_334">334</a></li>
-  <li>Detours on mountain-sides,&nbsp;<a href="#Page_3">3</a></li>
-  <li>Deviation, limits of,&nbsp;<a href="#Page_6">6</a>
-     <ul class="IX none">
-     <li>of centre line,&nbsp;<a href="#Page_12">12</a></li>
-     <li>of levels,&nbsp;<a href="#Page_12">12</a></li>
-     </ul></li>
-  <li>Diagram sketches of bridges,&nbsp;<a href="#Page_149">149</a></li>
-  <li>Diamond crossing,&nbsp;<a href="#Page_237">237</a></li>
-  <li>Disc or ground signals,&nbsp;<a href="#Page_322">322</a>
-     <ul class="IX none">
-     <li>wheels,&nbsp;<a href="#Page_48">48</a></li>
-     </ul></li>
-  <li>Distant signal,&nbsp;<a href="#Page_18">18</a>, <a href="#Page_314">314</a>, <a href="#Page_322">322</a></li>
-  <li>Diversion of roads, etc., <a href="#Page_6">6</a></li>
-  <li>Dobbin-cart,&nbsp;<a href="#Page_67">67</a></li>
-  <li>Dock platforms,&nbsp;<a href="#Page_251">251</a></li>
-  <li>Double-line junction,&nbsp;<a href="#Page_231">231</a>
-     <ul class="IX none">
-     <li>slip points,&nbsp;<a href="#Page_233">233</a></li>
-     </ul></li>
-  <li>Dry stone backing,&nbsp;<a href="#Page_162">162</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">E</li>
-</ul>
-<ul class="IX none">
-  <li>Earthworks,&nbsp;<a href="#Page_60">60</a></li>
-  <li>Edge rails,&nbsp;<a href="#Page_185">185</a></li>
-  <li>Electric motive-power,&nbsp;<a href="#Page_355">355</a>
-     <ul class="IX none">
-     <li>repeater,&nbsp;<a href="#Page_22">22</a>, <a href="#Page_334">334</a></li>
-     <li>train-staff instrument,&nbsp;<a href="#Page_344">344</a></li>
-     </ul></li>
-  <li>Embankment on bog,&nbsp;<a href="#Page_71">71</a></li>
-  <li>Engine bogie,&nbsp;<a href="#Page_53">53</a>, <a href="#Page_56">56</a>, <a href="#Page_304">304</a>
-     <ul class="IX none">
-     <li>triangle,&nbsp;<a href="#Page_290">290</a></li>
-     </ul></li>
-  <li>Engine turntables,&nbsp;<a href="#Page_27">27</a>, <a href="#Page_289">289</a></li>
-  <li>Enlargements on parliamentary plans,&nbsp;<a href="#Page_16">16</a></li>
-  <li>Entrances to tunnels,&nbsp;<a href="#Page_176">176</a></li>
-  <li>Estimate,&nbsp;<a href="#Page_14">14</a></li>
-  <li>Expansion of rails,&nbsp;<a href="#Page_228">228</a></li>
-  <li>Extract from Government Standing Orders and Regulations,&nbsp;<a href="#Page_6">6</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">F</li>
-</ul>
-<ul class="IX none">
-  <li>Facing-bolt lock,&nbsp;<a href="#Page_315">315</a>
-     <ul class="IX none">
-     <li>points,&nbsp;<a href="#Page_20">20</a>
-       <ul class="IX none">
-       <li>distance,&nbsp;<a href="#Page_20">20</a></li>
-       </ul></li>
-     <li>point locks,&nbsp;<a href="#Page_22">22</a></li>
-     </ul></li>
-  <li>Fang clips,&nbsp;<a href="#Page_224">224</a></li>
-  <li>Fastenings,&nbsp;<a href="#Page_218">218</a></li>
-  <li>Fences enclosing line,&nbsp;<a href="#Page_14">14</a>, <a href="#Page_73">73</a>
-     <ul class="IX none">
-     <li>on bridges,&nbsp;<a href="#Page_10">10</a></li>
-     <li>on road approaches,&nbsp;<a href="#Page_10">10</a></li>
-     </ul></li>
-  <li>Fish bolts,&nbsp;<a href="#Page_203">203</a>, <a href="#Page_220">220</a>
-     <ul class="IX none">
-     <li>plates,&nbsp;<a href="#Page_188">188</a>, <a href="#Page_203">203</a></li>
-     <li>plate liners,&nbsp;<a href="#Page_206">206</a></li>
-     </ul></li>
-  <li>Flag signals,&nbsp;<a href="#Page_313">313</a></li>
-  <li>Flag-top culverts,&nbsp;<a href="#Page_76">76</a></li>
-  <li>Flange rail,&nbsp;<a href="#Page_191">191</a></li>
-  <li>Floor or deck of girder bridges,&nbsp;<a href="#Page_133">133</a></li>
-  <li>Floors for goods-sheds,&nbsp;<a href="#Page_280">280</a></li>
-  <li>Flying junction,&nbsp;<a href="#Page_231">231</a></li>
-  <li>Fog or detonator signals,&nbsp;<a href="#Page_334">334</a></li>
-  <li>Footbridges,&nbsp;<a href="#Page_26">26</a>, <a href="#Page_147">147</a>, <a href="#Page_149">149</a></li>
-  <li>Footings of foundations,&nbsp;<a href="#Page_111">111</a></li>
-  <li>Foundations,&nbsp;<a href="#Page_111">111</a></li>
-  <li>Four-line system,&nbsp;<a href="#Page_351">351</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">G</li>
-</ul>
-<ul class="IX none">
-  <li>Gantry crane,&nbsp;<a href="#Page_294">294</a></li>
-  <li>Gate-alarm,&nbsp;<a href="#Page_336">336</a></li>
-  <li>Gates for level crossings,&nbsp;<a href="#Page_74">74</a></li>
-  <li>Gauge of railways,&nbsp;<a href="#Page_37">37</a>, <a href="#Page_38">38</a></li>
-  <li>Girder bridges,&nbsp;<a href="#Page_110">110</a></li>
-  <li>Glazed roofs over platforms,&nbsp;<a href="#Page_272">272</a></li>
-  <li>Goliath crane,&nbsp;<a href="#Page_297">297</a></li>
-  <li>Goods-sheds,&nbsp;<a href="#Page_273">273</a></li>
-  <li>Government grants to railways,&nbsp;<a href="#Page_349">349</a>
-     <ul class="IX none">
-     <li>Standing Orders,&nbsp;<a href="#Page_4">4</a>, <a href="#Page_6">6</a></li>
-     </ul></li>
-  <li>Gradient alterations,&nbsp;<a href="#Page_12">12</a></li>
-  <li>Gradients,&nbsp;<a href="#Page_42">42</a>
-     <ul class="IX none">
-     <li>influencing loads,&nbsp;<a href="#Page_43">43</a></li>
-     <li>in tunnels,&nbsp;<a href="#Page_166">166</a></li>
-     </ul></li>
-  <li>Gravel ballast,&nbsp;<a href="#Page_225">225</a>
-     <ul class="IX none">
-     <li>foundations,&nbsp;<a href="#Page_113">113</a></li>
-     </ul></li>
-  <li>Guard-rails,&nbsp;<a href="#Page_51">51</a></li>
-  <li>Guide-piles,&nbsp;<a href="#Page_127">127</a></li>
-</ul>
-
-<p><a name="Page_363" id="Page_363"></a><span class="pagenum">[Pg 363]</span></p>
-<ul class="IX none">
-<li class="indent">H</li>
-</ul>
-
-<ul class="IX none">
-  <li>Half-round sleepers,&nbsp;<a href="#Page_211">211</a></li>
-  <li>Hand-brakes on trucks,&nbsp;<a href="#Page_46">46</a></li>
-  <li>Headings in tunnels,&nbsp;<a href="#Page_169">169</a></li>
-  <li>Headway and span of public-road bridges,&nbsp;<a href="#Page_10">10</a></li>
-  <li>Height of platforms,&nbsp;<a href="#Page_24">24</a></li>
-  <li>Heights of embankments,&nbsp;<a href="#Page_10">10</a></li>
-  <li>High-level viaduct,&nbsp;<a href="#Page_81">81</a>, <a href="#Page_83">83</a></li>
-  <li>High-speed running,&nbsp;<a href="#Page_354">354</a></li>
-  <li>Home signals,&nbsp;<a href="#Page_18">18</a>, <a href="#Page_314">314</a></li>
-  <li>Houses of labouring classes,&nbsp;<a href="#Page_10">10</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">I</li>
-</ul>
-<ul class="IX none">
-  <li>Inclination of ramps,&nbsp;<a href="#Page_26">26</a></li>
-  <li>Inside keys for chairs,&nbsp;<a href="#Page_207">207</a></li>
-  <li>Inspection of new line,&nbsp;<a href="#Page_18">18</a>
-     <ul class="IX none">
-     <li>of tunnel work,&nbsp;<a href="#Page_176">176</a></li>
-     </ul></li>
-  <li>Interlocking of signals,&nbsp;<a href="#Page_22">22</a>, <a href="#Page_314">314</a>, <a href="#Page_330">330</a></li>
-  <li>Iron-tube tunnels,&nbsp;<a href="#Page_179">179</a></li>
-  <li>Island-platform station,&nbsp;<a href="#Page_258">258</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">J</li>
-</ul>
-<ul class="IX none">
-  <li>Jack-arches of brickwork,&nbsp;<a href="#Page_145">145</a>
-     <ul class="IX none">
-     <li>of concrete,&nbsp;<a href="#Page_139">139</a></li>
-     </ul></li>
-  <li>Jib crane,&nbsp;<a href="#Page_296">296</a></li>
-  <li>Jim Crow,&nbsp;<a href="#Page_239">239</a></li>
-  <li>Junction signals,&nbsp;<a href="#Page_20">20</a>, <a href="#Page_323">323</a>
-     <ul class="IX none">
-     <li>with existing line,&nbsp;<a href="#Page_6">6</a></li>
-     </ul></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">K</li>
-</ul>
-<ul class="IX none">
-  <li>Keys for chairs,&nbsp;<a href="#Page_207">207</a></li>
-  <li>Kinsua Viaduct,&nbsp;<a href="#Page_97">97</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">L</li>
-</ul>
-<ul class="IX none">
-  <li>Lavatories and conveniences,&nbsp;<a href="#Page_260">260</a></li>
-  <li>Laying permanent way,&nbsp;<a href="#Page_225">225</a></li>
-  <li>Level crossings,&nbsp;<a href="#Page_10">10</a></li>
-  <li>Life of steel rails,&nbsp;<a href="#Page_193">193</a></li>
-  <li>Lift-bridge,&nbsp;<a href="#Page_87">87</a></li>
-  <li>Light railways standard gauge,&nbsp;<a href="#Page_41">41</a></li>
-  <li>Limits of deviation,&nbsp;<a href="#Page_6">6</a>, <a href="#Page_16">16</a></li>
-  <li>Loa Viaduct,&nbsp;<a href="#Page_102">102</a></li>
-  <li>Loads of locomotive engines,&nbsp;<a href="#Page_44">44</a></li>
-  <li>Location of railway,&nbsp;<a href="#Page_1">1</a></li>
-  <li>Lock and block signals,&nbsp;<a href="#Page_342">342</a>, <a href="#Page_353">353</a></li>
-  <li>Longitudinal sleepers,&nbsp;<a href="#Page_210">210</a></li>
-  <li>Low viaduct arching,&nbsp;<a href="#Page_129">129</a></li>
-  <li>Low-level viaduct,&nbsp;<a href="#Page_81">81</a>, <a href="#Page_83">83</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">M</li>
-</ul>
-<ul class="IX none">
-  <li>Made ground,&nbsp;<a href="#Page_111">111</a></li>
-  <li>Marking steel rails,&nbsp;<a href="#Page_195">195</a></li>
-  <li>Mechanical drills,&nbsp;<a href="#Page_172">172</a>
-     <ul class="IX none">
-     <li>gates,&nbsp;<a href="#Page_335">335</a></li>
-     </ul></li>
-  <li>Mile-posts,&nbsp;<a href="#Page_30">30</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">N</li>
-</ul>
-<ul class="IX none">
-  <li>Names of stations,&nbsp;<a href="#Page_24">24</a></li>
-  <li>Narrow-gauge railways,&nbsp;<a href="#Page_40">40</a></li>
-  <li>Natural features of country,&nbsp;<a href="#Page_1">1</a>
-     <ul class="IX none">
-     <li>ground,&nbsp;<a href="#Page_111">111</a></li>
-     </ul></li>
-  <li>Navigable rivers,&nbsp;<a href="#Page_81">81</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">O</li>
-</ul>
-<ul class="IX none">
-  <li>Occupation bridges,&nbsp;<a href="#Page_110">110</a></li>
-  <li>Ordinary crossing,&nbsp;<a href="#Page_235">235</a></li>
-  <li>Ordnance maps,&nbsp;<a href="#Page_3">3</a></li>
-  <li>Outside guard-rails,&nbsp;<a href="#Page_53">53</a>
-     <ul class="IX none">
-     <li>keys for chairs,&nbsp;<a href="#Page_207">207</a></li>
-     </ul></li>
-  <li>Over-line arch bridges,&nbsp;<a href="#Page_103">103</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">P</li>
-</ul>
-<ul class="IX none">
-  <li>Parapets on viaducts,&nbsp;<a href="#Page_28">28</a></li>
-  <li>Parliamentary estimate,&nbsp;<a href="#Page_14">14</a>
-     <ul class="IX none">
-     <li>plan and section,&nbsp;<a href="#Page_6">6</a>, <a href="#Page_8">8</a></li>
-     </ul></li>
-  <li>Pedestal water-tanks,&nbsp;<a href="#Page_302">302</a></li>
-  <li>Piers of cast iron,&nbsp;<a href="#Page_97">97</a>
-     <ul class="IX none">
-     <li>of masonry,&nbsp;<a href="#Page_95">95</a></li>
-     <li>of timber,&nbsp;<a href="#Page_102">102</a></li>
-     <li>of wrought-iron and steel,&nbsp;<a href="#Page_97">97</a></li>
-     </ul></li>
-  <li>Pile foundations,&nbsp;<a href="#Page_114">114</a></li>
-  <li>Plate-iron troughing,&nbsp;<a href="#Page_143">143</a></li>
-  <li>Platform roofs,&nbsp;<a href="#Page_264">264</a></li>
-  <li>Platforms (requirements of), <a href="#Page_24">24</a></li>
-  <li>Plenum system of sinking,&nbsp;<a href="#Page_119">119</a></li>
-  <li>Pneumatic process of sinking,&nbsp;<a href="#Page_129">129</a></li>
-  <li>Points, or switches,&nbsp;<a href="#Page_235">235</a></li>
-  <li>Portage viaduct,&nbsp;<a href="#Page_102">102</a></li>
-  <li>Power to purchase land,&nbsp;<a href="#Page_6">6</a></li>
-  <li>Preservation of timber,&nbsp;<a href="#Page_211">211</a></li>
-  <li>Private-road bridges,&nbsp;<a href="#Page_110">110</a></li>
-  <li>Provincial grants to railways,&nbsp;<a href="#Page_349">349</a></li>
-  <li>Public-road bridges,&nbsp;<a href="#Page_10">10</a>, <a href="#Page_103">103</a>
-     <ul class="IX none">
-     <li>level crossing,&nbsp;<a href="#Page_8">8</a></li>
-     </ul></li>
-</ul>
-
-<p><a name="Page_364" id="Page_364"></a><span class="pagenum">[Pg 364]</span></p>
-<ul class="IX none">
-<li class="indent">R</li>
-</ul>
-
-<ul class="IX none">
-  <li>Radial axle-boxes,&nbsp;<a href="#Page_58">58</a></li>
-  <li>Rails,&nbsp;<a href="#Page_182">182</a></li>
-  <li>Railway bills,&nbsp;<a href="#Page_16">16</a>
-     <ul class="IX none">
-     <li>Clauses Act,&nbsp;<a href="#Page_6">6</a></li>
-     <li>fences,&nbsp;<a href="#Page_14">14</a></li>
-     <li>slope,&nbsp;<a href="#Page_61">61</a>, <a href="#Page_66">66</a>, <a href="#Page_72">72</a></li>
-     </ul></li>
-  <li>Railways of different ranks,&nbsp;<a href="#Page_348">348</a></li>
-  <li>Ramps to platforms,&nbsp;<a href="#Page_24">24</a></li>
-  <li>Recommendations as to working of railways,&nbsp;<a href="#Page_30">30</a></li>
-  <li>Rectangular running-sheds,&nbsp;<a href="#Page_289">289</a></li>
-  <li>Reduced speed on curves,&nbsp;<a href="#Page_50">50</a></li>
-  <li>Refuge sidings,&nbsp;<a href="#Page_31">31</a>, <a href="#Page_351">351</a></li>
-  <li>Relative costs of narrow-gauge and light railways,&nbsp;<a href="#Page_41">41</a></li>
-  <li>Renewal of under-line bridges,&nbsp;<a href="#Page_151">151</a></li>
-  <li>Repeater signal,&nbsp;<a href="#Page_22">22</a>, <a href="#Page_334">334</a></li>
-  <li>Requirements of Board of Trade,&nbsp;<a href="#Page_18">18</a></li>
-  <li>Retaining walls,&nbsp;<a href="#Page_159">159</a></li>
-  <li>Reverse curves,&nbsp;<a href="#Page_51">51</a></li>
-  <li>Roadside station,&nbsp;<a href="#Page_253">253</a></li>
-  <li>Rock foundations,&nbsp;<a href="#Page_113">113</a></li>
-  <li>Rocking-bar,&nbsp;<a href="#Page_316">316</a></li>
-  <li>Roof-principals,&nbsp;<a href="#Page_264">264</a></li>
-  <li>Roofs over roadside platforms,&nbsp;<a href="#Page_272">272</a></li>
-  <li>Rope-haulage,&nbsp;<a href="#Page_49">49</a></li>
-  <li>Route of railway,&nbsp;<a href="#Page_1">1</a></li>
-  <li>Royal assent,&nbsp;<a href="#Page_16">16</a></li>
-  <li>Runaway points,&nbsp;<a href="#Page_233">233</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">S</li>
-</ul>
-<ul class="IX none">
-  <li>Safety-points,&nbsp;<a href="#Page_24">24</a>, <a href="#Page_319">319</a></li>
-  <li>Sandy foundations,&nbsp;<a href="#Page_113">113</a></li>
-  <li>Scales for Parliamentary plans,&nbsp;<a href="#Page_6">6</a>, <a href="#Page_16">16</a></li>
-  <li>Scissors cross-over,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Screw piles,&nbsp;<a href="#Page_114">114</a></li>
-  <li>Semaphore signals,&nbsp;<a href="#Page_313">313</a></li>
-  <li>Semi-circular running-sheds,&nbsp;<a href="#Page_289">289</a></li>
-  <li>Separate lines for through traffic,&nbsp;<a href="#Page_358">358</a></li>
-  <li>Service roads,&nbsp;<a href="#Page_69">69</a></li>
-  <li>Shafts in tunnels,&nbsp;<a href="#Page_167">167</a></li>
-  <li>Sheeting-piles,&nbsp;<a href="#Page_127">127</a></li>
-  <li>Side-cutting,&nbsp;<a href="#Page_61">61</a></li>
-  <li>Side recesses in tunnels,&nbsp;<a href="#Page_176">176</a></li>
-  <li>Sidings,&nbsp;<a href="#Page_24">24</a></li>
-  <li>Signal-cabins,&nbsp;<a href="#Page_328">328</a></li>
-  <li>Signal-detector,&nbsp;<a href="#Page_315">315</a>, <a href="#Page_318">318</a></li>
-  <li>Signals,&nbsp;<a href="#Page_313">313</a>
-     <ul class="IX none">
-     <li>at junctions,&nbsp;<a href="#Page_20">20</a>, <a href="#Page_323">323</a></li>
-     </ul></li>
-  <li>Signals (requirements of), <a href="#Page_20">20</a></li>
-  <li>Six-wheeled carriage,&nbsp;<a href="#Page_54">54</a></li>
-  <li>Sleepers,&nbsp;<a href="#Page_209">209</a></li>
-  <li>Slip-points,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Slope of cutting,&nbsp;<a href="#Page_61">61</a>
-     <ul class="IX none">
-     <li>of embankment,&nbsp;<a href="#Page_66">66</a></li>
-     </ul></li>
-  <li>Slotted signals,&nbsp;<a href="#Page_326">326</a></li>
-  <li>Snake-heads,&nbsp;<a href="#Page_184">184</a></li>
-  <li>Soft deep bog,&nbsp;<a href="#Page_70">70</a></li>
-  <li>Soiling earthwork,&nbsp;<a href="#Page_66">66</a></li>
-  <li>Sorting-sidings,&nbsp;<a href="#Page_285">285</a></li>
-  <li>Span and headway of P. R. bridges,&nbsp;<a href="#Page_10">10</a></li>
-  <li>Spans of large railway bridges,&nbsp;<a href="#Page_158">158</a></li>
-  <li>Spikes,&nbsp;<a href="#Page_222">222</a></li>
-  <li>Spirals,&nbsp;<a href="#Page_35">35</a></li>
-  <li>Spoil-bank,&nbsp;<a href="#Page_60">60</a></li>
-  <li>Sprags,&nbsp;<a href="#Page_46">46</a></li>
-  <li>Square crossing,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Standing orders,&nbsp;<a href="#Page_4">4</a>, <a href="#Page_6">6</a></li>
-  <li>Starting-signal,&nbsp;<a href="#Page_18">18</a>, <a href="#Page_314">314</a></li>
-  <li>Station buildings,&nbsp;<a href="#Page_260">260</a>
-     <ul class="IX none">
-     <li>roofs,&nbsp;<a href="#Page_264">264</a></li>
-     </ul></li>
-  <li>Stations,&nbsp;<a href="#Page_248">248</a>
-     <ul class="IX none">
-     <li>near viaducts,&nbsp;<a href="#Page_24">24</a></li>
-     <li>on gradients,&nbsp;<a href="#Page_26">26</a></li>
-     </ul></li>
-  <li>Steel and wrought-iron sleepers,&nbsp;<a href="#Page_217">217</a>
-     <ul class="IX none">
-     <li>rails,&nbsp;<a href="#Page_190">190</a></li>
-     </ul></li>
-  <li>Steps for side-lying ground,&nbsp;<a href="#Page_70">70</a>
-     <ul class="IX none">
-     <li>of staircases,&nbsp;<a href="#Page_26">26</a></li>
-     </ul></li>
-  <li>Stone sleepers,&nbsp;<a href="#Page_210">210</a></li>
-  <li>Strain on steel,&nbsp;<a href="#Page_27">27</a>
-     <ul class="IX none">
-     <li>on wrought-iron,&nbsp;<a href="#Page_27">27</a></li>
-     </ul></li>
-  <li>Suburban traffic,&nbsp;<a href="#Page_352">352</a></li>
-  <li>Subways,&nbsp;<a href="#Page_26">26</a></li>
-  <li>Super-elevation of rail,&nbsp;<a href="#Page_230">230</a></li>
-  <li>Supervision of tunnel-work,&nbsp;<a href="#Page_176">176</a></li>
-  <li>Swing-bridges,&nbsp;<a href="#Page_83">83</a>, <a href="#Page_87">87</a></li>
-  <li>Switches or points,&nbsp;<a href="#Page_235">235</a></li>
-  <li>Syphon culverts,&nbsp;<a href="#Page_79">79</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">T</li>
-</ul>
-<ul class="IX none">
-  <li>Tamping-bar,&nbsp;<a href="#Page_239">239</a></li>
-  <li>Terminal station,&nbsp;<a href="#Page_253">253</a></li>
-  <li>Tests for steel rails,&nbsp;<a href="#Page_194">194</a></li>
-  <li>Three-throw switches,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Thrust-girders for retaining walls,&nbsp;<a href="#Page_161">161</a></li>
-  <li>Tie-bars,&nbsp;<a href="#Page_224">224</a></li>
-  <li>Timber bridges,&nbsp;<a href="#Page_95">95</a></li>
-  <li>Timbering of tunnels,&nbsp;<a href="#Page_170">170</a></li>
-  <li>Timber-pile foundations,&nbsp;<a href="#Page_114">114</a></li>
-  <li>Time for construction,&nbsp;<a href="#Page_18">18</a></li>
-  <li><a name="ixtip"></a>Tip head, <a href="#Page_67">67</a>
-     <a name="Page_365" id="Page_365"></a><span class="pagenum">[Pg 365]</span></li>
-  <li>Tip-waggon,&nbsp;<a href="#Page_69">69</a></li>
-  <li>Tools for permanent way,&nbsp;<a href="#Page_239">239</a>
-     <ul class="IX none">
-     <li>for tunnel-work,&nbsp;<a href="#Page_172">172</a></li>
-     </ul></li>
-  <li>Trailing-points,&nbsp;<a href="#Page_20">20</a></li>
-  <li>Train-staff on single line,&nbsp;<a href="#Page_342">342</a></li>
-  <li>Train-tickets,&nbsp;<a href="#Page_343">343</a></li>
-  <li>Tramplates of cast-iron,&nbsp;<a href="#Page_184">184</a></li>
-  <li>Tramway rails,&nbsp;<a href="#Page_199">199</a></li>
-  <li>Trap-points,&nbsp;<a href="#Page_319">319</a></li>
-  <li>Travelling-crane,&nbsp;<a href="#Page_296">296</a></li>
-  <li>Traversing bridge,&nbsp;<a href="#Page_85">85</a></li>
-  <li>Trimming slopes,&nbsp;<a href="#Page_72">72</a></li>
-  <li>Trough girders,&nbsp;<a href="#Page_135">135</a></li>
-  <li>Tunnel faces, or entrance,&nbsp;<a href="#Page_176">176</a>
-     <ul class="IX none">
-     <li>headings,&nbsp;<a href="#Page_169">169</a></li>
-     <li>sections,&nbsp;<a href="#Page_176">176</a></li>
-     <li>shafts,&nbsp;<a href="#Page_167">167</a></li>
-     </ul></li>
-  <li>Tunnels,&nbsp;<a href="#Page_6">6</a>, <a href="#Page_10">10</a>, <a href="#Page_162">162</a>
-     <ul class="IX none">
-     <li>composed of cast-iron segments,&nbsp;<a href="#Page_179">179</a></li>
-     <li>drainage of,&nbsp;<a href="#Page_166">166</a></li>
-     <li>through cities,&nbsp;<a href="#Page_178">178</a></li>
-     <li>under rivers,&nbsp;<a href="#Page_181">181</a></li>
-     </ul></li>
-  <li>Turn-out,&nbsp;<a href="#Page_233">233</a></li>
-  <li>Turntables,&nbsp;<a href="#Page_287">287</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">U</li>
-</ul>
-<ul class="IX none">
-  <li>Under-line arch bridges,&nbsp;<a href="#Page_103">103</a>, <a href="#Page_129">129</a></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">V</li>
-</ul>
-<ul class="IX none">
-  <li>Vacuum system of sinking,&nbsp;<a href="#Page_119">119</a></li>
-  <li>Verandah on platform,&nbsp;<a href="#Page_261">261</a></li>
-  <li>Viaduct parapets,&nbsp;<a href="#Page_28">28</a></li>
-  <li>Viaducts of timber,&nbsp;<a href="#Page_95">95</a>
-     <ul class="IX none">
-     <li>over rivers,&nbsp;<a href="#Page_83">83</a></li>
-     </ul></li>
-  <li>Viaducts over valleys,&nbsp;<a href="#Page_91">91</a>
-     <ul class="IX none">
-     <li>to be shown on section,&nbsp;<a href="#Page_10">10</a></li>
-     </ul></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">W</li>
-</ul>
-<ul class="IX none">
-  <li>Waggon turn-table,&nbsp;<a href="#Page_292">292</a></li>
-  <li>Waiting-rooms,&nbsp;<a href="#Page_251">251</a></li>
-  <li>Warehouse crane,&nbsp;<a href="#Page_294">294</a></li>
-  <li>Water-column,&nbsp;<a href="#Page_302">302</a></li>
-  <li>Water-jet piles,&nbsp;<a href="#Page_116">116</a></li>
-  <li>Water-tables,&nbsp;<a href="#Page_227">227</a></li>
-  <li>Water-tanks,&nbsp;<a href="#Page_299">299</a></li>
-  <li>Wear of fish-plates,&nbsp;<a href="#Page_205">205</a></li>
-  <li>Wear of steel rails,&nbsp;<a href="#Page_193">193</a></li>
-  <li>Weeping-holes,&nbsp;<a href="#Page_161">161</a>, <a href="#Page_174">174</a></li>
-  <li>Weights of locomotive engines,&nbsp;<a href="#Page_304">304</a></li>
-  <li>Well foundations,&nbsp;<a href="#Page_123">123</a></li>
-  <li>Wheel-base of engine bogie,&nbsp;<a href="#Page_59">59</a></li>
-  <li>Wheel-guards on viaducts,&nbsp;<a href="#Page_28">28</a></li>
-  <li>Widths of public-road bridges,&nbsp;<a href="#Page_10">10</a></li>
-  <li>Winding engines,&nbsp;<a href="#Page_185">185</a></li>
-  <li>Wind-pressure,&nbsp;<a href="#Page_28">28</a></li>
-  <li>Wooden-centre wheels,&nbsp;<a href="#Page_48">48</a></li>
-  <li>Wooden culverts,&nbsp;<a href="#Page_76">76</a>
-     <ul class="IX none">
-     <li>screws,&nbsp;<a href="#Page_223">223</a></li>
-     <li>tramway,&nbsp;<a href="#Page_182">182</a></li>
-     <li>water-tanks,&nbsp;<a href="#Page_301">301</a></li>
-     </ul></li>
-  <li>Working plans and sections,&nbsp;<a href="#Page_32">32</a></li>
-  <li>Wrought-iron column piers,&nbsp;<a href="#Page_97">97</a>
-     <ul class="IX none">
-     <li>and steel sleepers,&nbsp;<a href="#Page_217">217</a></li>
-     <li>piles,&nbsp;<a href="#Page_116">116</a></li>
-     <li>rails,&nbsp;<a href="#Page_186">186</a></li>
-     <li>water-tanks,&nbsp;<a href="#Page_301">301</a></li>
-     </ul></li>
-</ul>
-
-<ul class="IX none">
-<li class="indent">Z</li>
-</ul>
-<ul class="IX none">
-  <li>Zigzags,&nbsp;<a href="#Page_35">35</a></li>
-</ul>
-
-<hr class="p4" />
-<p class="center muchsmaller">PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, LONDON AND BECCLES.</p>
-</div><!--end of index-->
-
-<!--383.png--><!--384.png-->
-
-<div class="chapter">
-
-<p class="p4 center"><strong>ENGINEERING, STRENGTH OF MATERIALS, ETC.</strong></p>
-
-<p class="hanging">
-THE STRENGTH OF MATERIALS AND STRUCTURES: the Strength of Materials as
-depending on their Quality and as ascertained by Testing Apparatus. By
-Sir <span class="sc">J. Anderson</span>, C.E., LL.D., F.R.S.E. With 66 Illustrations. Crown
-<abbr title="octavo">8vo</abbr>, 3<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-
-<p class="hanging">
-RAILWAY APPLIANCES: a Description of Details of Railway Construction
-subsequent to the completion of the Earthworks and Structures. By Sir
-<span class="sc">John Wolfe Barry</span>, K.C.B., F.R.S. With 218 Illustrations. Crown <abbr title="octavo">8vo</abbr>,
-4<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-
-<p class="hanging">
-MECHANICS APPLIED TO ENGINEERING. By <span class="sc">John Goodman</span>, Wh.Sch.,
-M.I.C.E., M.I.M.E., Professor of Engineering in the University of
-Leeds. With 714 Illustrations and numerous Examples. Crown <abbr title="octavo">8vo</abbr>, 9<i class="money"><abbr title="shillings">s.</abbr></i>
-net.</p>
-
-<p class="hanging">
-RAILWAY APPLIANCES AND OPERATIONS. For the Use of Railway Employés. By
-<span class="sc">Edward S. Hadley</span>, the Great Western Railway’s Divisional
-Superintendent’s Office, Newport, Monmouth. [<i>In the press.</i></p>
-
-<p class="hanging">
-ENGINEER’S VALUING ASSISTANT: being a Practical Treatise on the
-Valuation of Colleries and Other Mines, etc. By <span class="sc">H. D. Hoskold</span>. With
-an Introductory Note by <span class="sc">Peter Gray</span>. <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">
-PRACTICAL HYDRAULIC (WATER SUPPLY AND DRAINAGE) TABLES AND DIAGRAMS.
-By <span class="sc">C. E. Housden</span>. With 6 Plates and 7 Diagrams in the Text. Crown
-<abbr title="octavo">8vo</abbr>, 3<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-PRACTICAL EARTHWORK TABLES. By <span class="sc">C. E. Housden</span>. With 9 Plates. Crown
-<abbr title="octavo">8vo</abbr>, 2<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-A POCKET-BOOK FOR MECHANICAL ENGINEERS. By <span class="sc">David Allan Low</span>
-(Whitworth Scholar), M.I.Mech.E., Professor of Engineering, East
-London Technical College. With over 1,000 specially prepared
-Illustrations. Fcp. <abbr title="octavo">8vo</abbr>, gilt edges, rounded corners. 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-MECHANICS FOR ENGINEERS: a Text-book of Intermediate Standard. With
-200 Diagrams and numerous Examples. By <span class="sc">Arthur Morley</span>, M.Sc.,
-Professor of Mechanical Engineering in University College, Nottingham.
-Crown <abbr title="octavo">8vo</abbr>, 4<i class="money"><abbr title="shillings">s.</abbr></i> net.</p>
-
-<p class="hanging">
-STRENGTH OF MATERIALS. By <span class="sc">Arthur Morley</span>, M.Sc., Professor of
-Mechanical Engineering in University College, Nottingham. With 248
-Diagrams and numerous Examples. <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">
-LIGHT RAILWAY CONSTRUCTION. By <span class="sc">Richard Marion Parkinson</span>, Assoc.
-M.Inst.C.E. With 85 Diagrams. <abbr title="octavo">8vo</abbr>, 10<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">
-GRAPHICS; or, the Art of Calculation by Drawing Lines, applied
-especially to Mechanical Engineering. By <span class="sc">Robert H. Smith</span>, formerly
-Professor of Engineering, Mason College, Birmingham. Part I. With
-separate Atlas of 29 Plates containing 97 Diagrams. <abbr title="octavo">8vo</abbr>, 15<i class="money"><abbr title="shillings">s.</abbr></i></p>
-<!--385.png-->
-
-<p class="hanging">
-THE THEORY OF STRESSES IN GIRDERS AND SIMILAR STRUCTURES; with
-Practical Observations on the Strength and other Properties of
-Materials. By <span class="sc">Bindon B. Stoney</span>, LL.D., F.R.S., M.I.C.E. With 5
-Plates and 143 Illustrations in the Text. Royal <abbr title="octavo">8vo</abbr>, 36<i class="money"><abbr title="shillings">s.</abbr></i></p>
-
-<p class="hanging">
-THE TESTING OF MATERIALS OF CONSTRUCTION. A Textbook for the
-Engineering Laboratory and a Collection of the Results of Experiment.
-By <span class="sc">W. Cawthorne Unwin</span>, F.R.S., B.Sc. With 5 Plates and 188
-Illustrations and Diagrams. <abbr title="octavo">8vo</abbr>, 16<i class="money"><abbr title="shillings">s.</abbr></i> net.</p>
-
-<p class="hanging">
-ENGINEERING CONSTRUCTION IN IRON, STEEL, AND TIMBER. By <span class="sc">William
-Henry Warren</span>. With 13 Folding Plates and 375 Diagrams. Medium
-<abbr title="octavo">8vo</abbr>, 16<i class="money"><abbr title="shillings">s.</abbr></i> net.</p>
-
-<p class="hanging">
-THE SEA COAST: Destruction, Littoral Drift, Protection. By <span class="sc">W. H.
-Wheeler</span>, M.Inst. C.E. With 38 Illustrations and Diagram. Medium <abbr title="octavo">8vo</abbr>,
-10<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">
-A PRACTICAL MANUAL OF TIDES AND WAVES. By <span class="sc">W. H. Wheeler</span>, M.Inst.
-C.E. With 19 Illustrations. <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="p2 center"><strong>MACHINE DRAWING AND DESIGN.</strong></p>
-
-<p class="hanging">
-AN INTRODUCTION TO MACHINE DRAWING AND DESIGN. By <span class="sc">David Allan Low</span>,
-M.I.Mech.E. With 153 Illustrations and Diagrams. Crown <abbr title="octavo">8vo</abbr>, 2<i class="money"><abbr title="shillings">s.</abbr></i>
-6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-A POCKET-BOOK FOR MECHANICAL ENGINEERS. By <span class="sc">David Allan Low</span>,
-M.I.Mech.E. Fcp. <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-THE DIAGRAM MEASURER. An Instrument for Measuring the Areas of
-Irregular Figures, and specially useful for determining the Mean
-Effective Pressure from Indicator Diagrams from Steam, Gas and other
-Engines. By <span class="sc">David Allan Low</span>, M.I.Mech.E. With full instructions,
-1<i class="money"><abbr title="shillings">s.</abbr></i></p>
-
-<p class="hanging">
-A MANUAL OF MACHINE DRAWING AND DESIGN. By <span class="sc">David Allan Low</span> and
-<span class="sc">Alfred William Bevis</span>. With over 700 Illustrations. <abbr title="octavo">8vo</abbr>, 7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-MACHINE DESIGN, CONSTRUCTION AND DRAWING: a Textbook for the Use of
-Young Engineers. By <span class="sc">Henry J. Spooner</span>, C.E., M.I.Mech.E., F.G.S.,
-etc., Director and Professor in the Polytechnic School of Engineering.
-With 86 Tables and numerous Exercises. Illustrated by over 1,400
-Drawings and Figures. <abbr title="octavo">8vo</abbr>, 10<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">
-MACHINE DRAWING AND DESIGN FOR BEGINNERS: an Introductory Work for the
-Use of Technical Students. By <span class="sc">Henry J. Spooner</span>, C.E., M.I.Mech.E.,
-F.G.S., etc., Director and Professor in the Polytechnic School of
-Engineering. Crown 4to, price 3<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i></p>
-
-<p class="hanging">
-THE ELEMENTS OF MACHINE DESIGN. <span class="sc">Part I.</span> General Principles; Strength
-of Materials; Rivets, Bolts, and other Fastenings; Journals and
-Shafting; Couplings; Pedestals; Transmission of Power by Gearing,
-Belting, Ropes, and Chains. By <span class="sc">W. Cawthorne Unwin</span>, LL.D., F.R.S.,
-B.Sc., M.I.C.E., Hon. Mem. Inst. Mech. E., Hon. Mem. Am. Soc. Mech.
-E., Foreign Hon. Mem. Am. Academy of Arts and Sciences. With 387 Figures. <abbr title="octavo">8vo</abbr>,
-7<i class="money"><abbr title="shillings">s.</abbr></i> 6<i class="money"><abbr title="pence">d.</abbr></i> net.</p>
-
-<p class="hanging">&ensp;<span class="sc">Part II.</span> Chiefly on Engine Details. With 259 Diagrams, etc. Crown <abbr title="octavo">8vo</abbr>, 6<i class="money"><abbr title="shillings">s.</abbr></i></p>
-
-<p class="p4 center smaller">LONGMANS, GREEN, &amp; CO.</p>
-
-<p class="center muchsmaller">LONDON, NEW YORK, BOMBAY, AND CALCUTTA.</p>
-</div><!--end book-->
-
-<div class="p4 chapter tnote">
-<h4>Transcriber’s Note:</h4>
-
-<p>Added unprinted punctuation, where appropriate. In screen view,
-page numbers for the text portions of the book are displayed in the
-right margin.</p>
-
-<p>For handheld devices, wide tables were split into two tables for
-easier viewing.</p>
-
-<p>Removed hyphen:</p>
-  <ul>
-  <li>page 69, <a href="#earth">earth-waggon</a> and <a href="#tiphead">tip-head</a></li>
-  <li>page 331, <a href="#wire">wire-bar</a></li>
-  <li>page 335, <a href="#signal">signal-man</a></li>
-  <li>index, <a href="#ixtip">tip-head</a></li>
-  </ul>
-<p>Added hypen:</p>
-  <ul>
-  <li>page 30, <a href="#half">half-mile</a></li>
-  <li>page 66, <a href="#chain">chain-peg</a></li>
-  <li>pages <a href="#water5">65</a>, <a href="#water6">66</a> and <a href="#water7">78</a>, water-table</li>
-  </ul>
-<p>Other changes:</p>
-  <ul>
-  <li>page 41 ‘transhipment’ to <a href="#trans">‘transshipment’</a></li>
-  <li>page 45 ‘steepier’ to <a href="#steeper">‘steeper’</a></li>
-  <li>page 48 ‘guage’ to <a href="#gauge1">‘gauge’</a></li>
-  <li>page 193 ‘guage’ to <a href="#gauge2">‘gauge’</a></li>
-  <li>page 193 ‘breaks’ to <a href="#brakes">‘brakes’</a></li>
-  <li>page 301 ‘petition’ to <a href="#partition">‘partition’</a></li>
-  <li>page 302 ‘close’ to <a href="#closed">‘closed’</a></li>
-  </ul>
-</div><!--end transcriber note-->
-
-
-
-
-
-
-
-<pre>
-
-
-
-
-
-End of Project Gutenberg's Railway Construction, by William Hemmingway Mills
-
-*** END OF THIS PROJECT GUTENBERG EBOOK RAILWAY CONSTRUCTION ***
-
-***** This file should be named 50696-h.htm or 50696-h.zip *****
-This and all associated files of various formats will be found in:
-        http://www.gutenberg.org/5/0/6/9/50696/
-
-Produced by Chris Curnow, Carol Brown, and the Online
-Distributed Proofreading Team at http://www.pgdp.net (This
-file was produced from images generously made available
-by The Internet Archive)
-
-
-Updated editions will replace the previous one--the old editions will
-be renamed.
-
-Creating the works from print editions not protected by U.S. copyright
-law means that no one owns a United States copyright in these works,
-so the Foundation (and you!) can copy and distribute it in the United
-States without permission and without paying copyright
-royalties. Special rules, set forth in the General Terms of Use part
-of this license, apply to copying and distributing Project
-Gutenberg-tm electronic works to protect the PROJECT GUTENBERG-tm
-concept and trademark. Project Gutenberg is a registered trademark,
-and may not be used if you charge for the eBooks, unless you receive
-specific permission. If you do not charge anything for copies of this
-eBook, complying with the rules is very easy. You may use this eBook
-for nearly any purpose such as creation of derivative works, reports,
-performances and research. They may be modified and printed and given
-away--you may do practically ANYTHING in the United States with eBooks
-not protected by U.S. copyright law. Redistribution is subject to the
-trademark license, especially commercial redistribution.
-
-START: FULL LICENSE
-
-THE FULL PROJECT GUTENBERG LICENSE
-PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK
-
-To protect the Project Gutenberg-tm mission of promoting the free
-distribution of electronic works, by using or distributing this work
-(or any other work associated in any way with the phrase "Project
-Gutenberg"), you agree to comply with all the terms of the Full
-Project Gutenberg-tm License available with this file or online at
-www.gutenberg.org/license.
-
-Section 1. General Terms of Use and Redistributing Project
-Gutenberg-tm electronic works
-
-1.A. By reading or using any part of this Project Gutenberg-tm
-electronic work, you indicate that you have read, understand, agree to
-and accept all the terms of this license and intellectual property
-(trademark/copyright) agreement. If you do not agree to abide by all
-the terms of this agreement, you must cease using and return or
-destroy all copies of Project Gutenberg-tm electronic works in your
-possession. If you paid a fee for obtaining a copy of or access to a
-Project Gutenberg-tm electronic work and you do not agree to be bound
-by the terms of this agreement, you may obtain a refund from the
-person or entity to whom you paid the fee as set forth in paragraph
-1.E.8.
-
-1.B. "Project Gutenberg" is a registered trademark. It may only be
-used on or associated in any way with an electronic work by people who
-agree to be bound by the terms of this agreement. There are a few
-things that you can do with most Project Gutenberg-tm electronic works
-even without complying with the full terms of this agreement. See
-paragraph 1.C below. There are a lot of things you can do with Project
-Gutenberg-tm electronic works if you follow the terms of this
-agreement and help preserve free future access to Project Gutenberg-tm
-electronic works. See paragraph 1.E below.
-
-1.C. The Project Gutenberg Literary Archive Foundation ("the
-Foundation" or PGLAF), owns a compilation copyright in the collection
-of Project Gutenberg-tm electronic works. Nearly all the individual
-works in the collection are in the public domain in the United
-States. If an individual work is unprotected by copyright law in the
-United States and you are located in the United States, we do not
-claim a right to prevent you from copying, distributing, performing,
-displaying or creating derivative works based on the work as long as
-all references to Project Gutenberg are removed. Of course, we hope
-that you will support the Project Gutenberg-tm mission of promoting
-free access to electronic works by freely sharing Project Gutenberg-tm
-works in compliance with the terms of this agreement for keeping the
-Project Gutenberg-tm name associated with the work. You can easily
-comply with the terms of this agreement by keeping this work in the
-same format with its attached full Project Gutenberg-tm License when
-you share it without charge with others.
-
-1.D. The copyright laws of the place where you are located also govern
-what you can do with this work. Copyright laws in most countries are
-in a constant state of change. If you are outside the United States,
-check the laws of your country in addition to the terms of this
-agreement before downloading, copying, displaying, performing,
-distributing or creating derivative works based on this work or any
-other Project Gutenberg-tm work. The Foundation makes no
-representations concerning the copyright status of any work in any
-country outside the United States.
-
-1.E. Unless you have removed all references to Project Gutenberg:
-
-1.E.1. The following sentence, with active links to, or other
-immediate access to, the full Project Gutenberg-tm License must appear
-prominently whenever any copy of a Project Gutenberg-tm work (any work
-on which the phrase "Project Gutenberg" appears, or with which the
-phrase "Project Gutenberg" is associated) is accessed, displayed,
-performed, viewed, copied or distributed:
-
-  This eBook is for the use of anyone anywhere in the United States and
-  most other parts of the world at no cost and with almost no
-  restrictions whatsoever. You may copy it, give it away or re-use it
-  under the terms of the Project Gutenberg License included with this
-  eBook or online at www.gutenberg.org. If you are not located in the
-  United States, you'll have to check the laws of the country where you
-  are located before using this ebook.
-
-1.E.2. If an individual Project Gutenberg-tm electronic work is
-derived from texts not protected by U.S. copyright law (does not
-contain a notice indicating that it is posted with permission of the
-copyright holder), the work can be copied and distributed to anyone in
-the United States without paying any fees or charges. If you are
-redistributing or providing access to a work with the phrase "Project
-Gutenberg" associated with or appearing on the work, you must comply
-either with the requirements of paragraphs 1.E.1 through 1.E.7 or
-obtain permission for the use of the work and the Project Gutenberg-tm
-trademark as set forth in paragraphs 1.E.8 or 1.E.9.
-
-1.E.3. If an individual Project Gutenberg-tm electronic work is posted
-with the permission of the copyright holder, your use and distribution
-must comply with both paragraphs 1.E.1 through 1.E.7 and any
-additional terms imposed by the copyright holder. Additional terms
-will be linked to the Project Gutenberg-tm License for all works
-posted with the permission of the copyright holder found at the
-beginning of this work.
-
-1.E.4. Do not unlink or detach or remove the full Project Gutenberg-tm
-License terms from this work, or any files containing a part of this
-work or any other work associated with Project Gutenberg-tm.
-
-1.E.5. Do not copy, display, perform, distribute or redistribute this
-electronic work, or any part of this electronic work, without
-prominently displaying the sentence set forth in paragraph 1.E.1 with
-active links or immediate access to the full terms of the Project
-Gutenberg-tm License.
-
-1.E.6. You may convert to and distribute this work in any binary,
-compressed, marked up, nonproprietary or proprietary form, including
-any word processing or hypertext form. However, if you provide access
-to or distribute copies of a Project Gutenberg-tm work in a format
-other than "Plain Vanilla ASCII" or other format used in the official
-version posted on the official Project Gutenberg-tm web site
-(www.gutenberg.org), you must, at no additional cost, fee or expense
-to the user, provide a copy, a means of exporting a copy, or a means
-of obtaining a copy upon request, of the work in its original "Plain
-Vanilla ASCII" or other form. Any alternate format must include the
-full Project Gutenberg-tm License as specified in paragraph 1.E.1.
-
-1.E.7. Do not charge a fee for access to, viewing, displaying,
-performing, copying or distributing any Project Gutenberg-tm works
-unless you comply with paragraph 1.E.8 or 1.E.9.
-
-1.E.8. You may charge a reasonable fee for copies of or providing
-access to or distributing Project Gutenberg-tm electronic works
-provided that
-
-* You pay a royalty fee of 20% of the gross profits you derive from
-  the use of Project Gutenberg-tm works calculated using the method
-  you already use to calculate your applicable taxes. The fee is owed
-  to the owner of the Project Gutenberg-tm trademark, but he has
-  agreed to donate royalties under this paragraph to the Project
-  Gutenberg Literary Archive Foundation. Royalty payments must be paid
-  within 60 days following each date on which you prepare (or are
-  legally required to prepare) your periodic tax returns. Royalty
-  payments should be clearly marked as such and sent to the Project
-  Gutenberg Literary Archive Foundation at the address specified in
-  Section 4, "Information about donations to the Project Gutenberg
-  Literary Archive Foundation."
-
-* You provide a full refund of any money paid by a user who notifies
-  you in writing (or by e-mail) within 30 days of receipt that s/he
-  does not agree to the terms of the full Project Gutenberg-tm
-  License. You must require such a user to return or destroy all
-  copies of the works possessed in a physical medium and discontinue
-  all use of and all access to other copies of Project Gutenberg-tm
-  works.
-
-* You provide, in accordance with paragraph 1.F.3, a full refund of
-  any money paid for a work or a replacement copy, if a defect in the
-  electronic work is discovered and reported to you within 90 days of
-  receipt of the work.
-
-* You comply with all other terms of this agreement for free
-  distribution of Project Gutenberg-tm works.
-
-1.E.9. If you wish to charge a fee or distribute a Project
-Gutenberg-tm electronic work or group of works on different terms than
-are set forth in this agreement, you must obtain permission in writing
-from both the Project Gutenberg Literary Archive Foundation and The
-Project Gutenberg Trademark LLC, the owner of the Project Gutenberg-tm
-trademark. Contact the Foundation as set forth in Section 3 below.
-
-1.F.
-
-1.F.1. Project Gutenberg volunteers and employees expend considerable
-effort to identify, do copyright research on, transcribe and proofread
-works not protected by U.S. copyright law in creating the Project
-Gutenberg-tm collection. Despite these efforts, Project Gutenberg-tm
-electronic works, and the medium on which they may be stored, may
-contain "Defects," such as, but not limited to, incomplete, inaccurate
-or corrupt data, transcription errors, a copyright or other
-intellectual property infringement, a defective or damaged disk or
-other medium, a computer virus, or computer codes that damage or
-cannot be read by your equipment.
-
-1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right
-of Replacement or Refund" described in paragraph 1.F.3, the Project
-Gutenberg Literary Archive Foundation, the owner of the Project
-Gutenberg-tm trademark, and any other party distributing a Project
-Gutenberg-tm electronic work under this agreement, disclaim all
-liability to you for damages, costs and expenses, including legal
-fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT
-LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE
-PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE THAT THE FOUNDATION, THE
-TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE
-LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
-INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH
-DAMAGE.
-
-1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a
-defect in this electronic work within 90 days of receiving it, you can
-receive a refund of the money (if any) you paid for it by sending a
-written explanation to the person you received the work from. If you
-received the work on a physical medium, you must return the medium
-with your written explanation. The person or entity that provided you
-with the defective work may elect to provide a replacement copy in
-lieu of a refund. If you received the work electronically, the person
-or entity providing it to you may choose to give you a second
-opportunity to receive the work electronically in lieu of a refund. If
-the second copy is also defective, you may demand a refund in writing
-without further opportunities to fix the problem.
-
-1.F.4. Except for the limited right of replacement or refund set forth
-in paragraph 1.F.3, this work is provided to you 'AS-IS', WITH NO
-OTHER WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
-LIMITED TO WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PURPOSE.
-
-1.F.5. Some states do not allow disclaimers of certain implied
-warranties or the exclusion or limitation of certain types of
-damages. If any disclaimer or limitation set forth in this agreement
-violates the law of the state applicable to this agreement, the
-agreement shall be interpreted to make the maximum disclaimer or
-limitation permitted by the applicable state law. The invalidity or
-unenforceability of any provision of this agreement shall not void the
-remaining provisions.
-
-1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the
-trademark owner, any agent or employee of the Foundation, anyone
-providing copies of Project Gutenberg-tm electronic works in
-accordance with this agreement, and any volunteers associated with the
-production, promotion and distribution of Project Gutenberg-tm
-electronic works, harmless from all liability, costs and expenses,
-including legal fees, that arise directly or indirectly from any of
-the following which you do or cause to occur: (a) distribution of this
-or any Project Gutenberg-tm work, (b) alteration, modification, or
-additions or deletions to any Project Gutenberg-tm work, and (c) any
-Defect you cause.
-
-Section 2. Information about the Mission of Project Gutenberg-tm
-
-Project Gutenberg-tm is synonymous with the free distribution of
-electronic works in formats readable by the widest variety of
-computers including obsolete, old, middle-aged and new computers. It
-exists because of the efforts of hundreds of volunteers and donations
-from people in all walks of life.
-
-Volunteers and financial support to provide volunteers with the
-assistance they need are critical to reaching Project Gutenberg-tm's
-goals and ensuring that the Project Gutenberg-tm collection will
-remain freely available for generations to come. In 2001, the Project
-Gutenberg Literary Archive Foundation was created to provide a secure
-and permanent future for Project Gutenberg-tm and future
-generations. To learn more about the Project Gutenberg Literary
-Archive Foundation and how your efforts and donations can help, see
-Sections 3 and 4 and the Foundation information page at
-www.gutenberg.org Section 3. Information about the Project Gutenberg
-Literary Archive Foundation
-
-The Project Gutenberg Literary Archive Foundation is a non profit
-501(c)(3) educational corporation organized under the laws of the
-state of Mississippi and granted tax exempt status by the Internal
-Revenue Service. The Foundation's EIN or federal tax identification
-number is 64-6221541. Contributions to the Project Gutenberg Literary
-Archive Foundation are tax deductible to the full extent permitted by
-U.S. federal laws and your state's laws.
-
-The Foundation's principal office is in Fairbanks, Alaska, with the
-mailing address: PO Box 750175, Fairbanks, AK 99775, but its
-volunteers and employees are scattered throughout numerous
-locations. Its business office is located at 809 North 1500 West, Salt
-Lake City, UT 84116, (801) 596-1887. Email contact links and up to
-date contact information can be found at the Foundation's web site and
-official page at www.gutenberg.org/contact
-
-For additional contact information:
-
-    Dr. Gregory B. Newby
-    Chief Executive and Director
-    gbnewby@pglaf.org
-
-Section 4. Information about Donations to the Project Gutenberg
-Literary Archive Foundation
-
-Project Gutenberg-tm depends upon and cannot survive without wide
-spread public support and donations to carry out its mission of
-increasing the number of public domain and licensed works that can be
-freely distributed in machine readable form accessible by the widest
-array of equipment including outdated equipment. Many small donations
-($1 to $5,000) are particularly important to maintaining tax exempt
-status with the IRS.
-
-The Foundation is committed to complying with the laws regulating
-charities and charitable donations in all 50 states of the United
-States. Compliance requirements are not uniform and it takes a
-considerable effort, much paperwork and many fees to meet and keep up
-with these requirements. We do not solicit donations in locations
-where we have not received written confirmation of compliance. To SEND
-DONATIONS or determine the status of compliance for any particular
-state visit www.gutenberg.org/donate
-
-While we cannot and do not solicit contributions from states where we
-have not met the solicitation requirements, we know of no prohibition
-against accepting unsolicited donations from donors in such states who
-approach us with offers to donate.
-
-International donations are gratefully accepted, but we cannot make
-any statements concerning tax treatment of donations received from
-outside the United States. U.S. laws alone swamp our small staff.
-
-Please check the Project Gutenberg Web pages for current donation
-methods and addresses. Donations are accepted in a number of other
-ways including checks, online payments and credit card donations. To
-donate, please visit: www.gutenberg.org/donate
-
-Section 5. General Information About Project Gutenberg-tm electronic works.
-
-Professor Michael S. Hart was the originator of the Project
-Gutenberg-tm concept of a library of electronic works that could be
-freely shared with anyone. For forty years, he produced and
-distributed Project Gutenberg-tm eBooks with only a loose network of
-volunteer support.
-
-Project Gutenberg-tm eBooks are often created from several printed
-editions, all of which are confirmed as not protected by copyright in
-the U.S. unless a copyright notice is included. Thus, we do not
-necessarily keep eBooks in compliance with any particular paper
-edition.
-
-Most people start at our Web site which has the main PG search
-facility: www.gutenberg.org
-
-This Web site includes information about Project Gutenberg-tm,
-including how to make donations to the Project Gutenberg Literary
-Archive Foundation, how to help produce our new eBooks, and how to
-subscribe to our email newsletter to hear about new eBooks.
-
-
-
-</pre>
-
-</body>
-</html>
diff --git a/old/50696-h/images/cover.jpg b/old/50696-h/images/cover.jpg
deleted file mode 100644
index 5ca4737..0000000
--- a/old/50696-h/images/cover.jpg
+++ /dev/null
diff --git a/old/50696-h/images/estimate_form.jpg b/old/50696-h/images/estimate_form.jpg
deleted file mode 100644
index f2fbf6d..0000000
--- a/old/50696-h/images/estimate_form.jpg
+++ /dev/null
diff --git a/old/50696-h/images/frontis.jpg b/old/50696-h/images/frontis.jpg
deleted file mode 100644
index 9a41c38..0000000
--- a/old/50696-h/images/frontis.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i005.jpg b/old/50696-h/images/i005.jpg
deleted file mode 100644
index 141ee7e..0000000
--- a/old/50696-h/images/i005.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i007.jpg b/old/50696-h/images/i007.jpg
deleted file mode 100644
index 7be40a5..0000000
--- a/old/50696-h/images/i007.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i009.jpg b/old/50696-h/images/i009.jpg
deleted file mode 100644
index 6620b48..0000000
--- a/old/50696-h/images/i009.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i011.jpg b/old/50696-h/images/i011.jpg
deleted file mode 100644
index 85ebbbb..0000000
--- a/old/50696-h/images/i011.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i013.jpg b/old/50696-h/images/i013.jpg
deleted file mode 100644
index 443702b..0000000
--- a/old/50696-h/images/i013.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i015.jpg b/old/50696-h/images/i015.jpg
deleted file mode 100644
index f6ba772..0000000
--- a/old/50696-h/images/i015.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i017.jpg b/old/50696-h/images/i017.jpg
deleted file mode 100644
index 203bba1..0000000
--- a/old/50696-h/images/i017.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i019.jpg b/old/50696-h/images/i019.jpg
deleted file mode 100644
index a1d6b75..0000000
--- a/old/50696-h/images/i019.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i021.jpg b/old/50696-h/images/i021.jpg
deleted file mode 100644
index 412ab3b..0000000
--- a/old/50696-h/images/i021.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i023.jpg b/old/50696-h/images/i023.jpg
deleted file mode 100644
index 973b326..0000000
--- a/old/50696-h/images/i023.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i025.jpg b/old/50696-h/images/i025.jpg
deleted file mode 100644
index 4500e11..0000000
--- a/old/50696-h/images/i025.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i034.jpg b/old/50696-h/images/i034.jpg
deleted file mode 100644
index 0f0fb0e..0000000
--- a/old/50696-h/images/i034.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i036.jpg b/old/50696-h/images/i036.jpg
deleted file mode 100644
index 2d9625d..0000000
--- a/old/50696-h/images/i036.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i052.jpg b/old/50696-h/images/i052.jpg
deleted file mode 100644
index 0a19f5f..0000000
--- a/old/50696-h/images/i052.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i055.jpg b/old/50696-h/images/i055.jpg
deleted file mode 100644
index 7f2244a..0000000
--- a/old/50696-h/images/i055.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i057.jpg b/old/50696-h/images/i057.jpg
deleted file mode 100644
index 41e6b21..0000000
--- a/old/50696-h/images/i057.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i062.jpg b/old/50696-h/images/i062.jpg
deleted file mode 100644
index 8d871eb..0000000
--- a/old/50696-h/images/i062.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i064.jpg b/old/50696-h/images/i064.jpg
deleted file mode 100644
index a32574b..0000000
--- a/old/50696-h/images/i064.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i068.jpg b/old/50696-h/images/i068.jpg
deleted file mode 100644
index 5b3f65c..0000000
--- a/old/50696-h/images/i068.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i077.jpg b/old/50696-h/images/i077.jpg
deleted file mode 100644
index e82a719..0000000
--- a/old/50696-h/images/i077.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i080.jpg b/old/50696-h/images/i080.jpg
deleted file mode 100644
index 3f5c941..0000000
--- a/old/50696-h/images/i080.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i082.jpg b/old/50696-h/images/i082.jpg
deleted file mode 100644
index 75db6e2..0000000
--- a/old/50696-h/images/i082.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i084.jpg b/old/50696-h/images/i084.jpg
deleted file mode 100644
index 1a9a9c3..0000000
--- a/old/50696-h/images/i084.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i086.jpg b/old/50696-h/images/i086.jpg
deleted file mode 100644
index aecba09..0000000
--- a/old/50696-h/images/i086.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i088.jpg b/old/50696-h/images/i088.jpg
deleted file mode 100644
index 953061e..0000000
--- a/old/50696-h/images/i088.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i090.jpg b/old/50696-h/images/i090.jpg
deleted file mode 100644
index dbbb6e3..0000000
--- a/old/50696-h/images/i090.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i092.jpg b/old/50696-h/images/i092.jpg
deleted file mode 100644
index 22b1732..0000000
--- a/old/50696-h/images/i092.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i094.jpg b/old/50696-h/images/i094.jpg
deleted file mode 100644
index 42a4c1b..0000000
--- a/old/50696-h/images/i094.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i096.jpg b/old/50696-h/images/i096.jpg
deleted file mode 100644
index 8ef376f..0000000
--- a/old/50696-h/images/i096.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i098.jpg b/old/50696-h/images/i098.jpg
deleted file mode 100644
index 7f04fcd..0000000
--- a/old/50696-h/images/i098.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i099.jpg b/old/50696-h/images/i099.jpg
deleted file mode 100644
index 7bc09ac..0000000
--- a/old/50696-h/images/i099.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i100.jpg b/old/50696-h/images/i100.jpg
deleted file mode 100644
index ca590f9..0000000
--- a/old/50696-h/images/i100.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i101.jpg b/old/50696-h/images/i101.jpg
deleted file mode 100644
index 16c6adb..0000000
--- a/old/50696-h/images/i101.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i104.jpg b/old/50696-h/images/i104.jpg
deleted file mode 100644
index 69422b7..0000000
--- a/old/50696-h/images/i104.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i105.jpg b/old/50696-h/images/i105.jpg
deleted file mode 100644
index 8e1ae79..0000000
--- a/old/50696-h/images/i105.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i106.jpg b/old/50696-h/images/i106.jpg
deleted file mode 100644
index 7f5ba5f..0000000
--- a/old/50696-h/images/i106.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i107.jpg b/old/50696-h/images/i107.jpg
deleted file mode 100644
index fc4bfb9..0000000
--- a/old/50696-h/images/i107.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i108.jpg b/old/50696-h/images/i108.jpg
deleted file mode 100644
index a4fce71..0000000
--- a/old/50696-h/images/i108.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i109.jpg b/old/50696-h/images/i109.jpg
deleted file mode 100644
index 6d77128..0000000
--- a/old/50696-h/images/i109.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i112.jpg b/old/50696-h/images/i112.jpg
deleted file mode 100644
index 3122c63..0000000
--- a/old/50696-h/images/i112.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i115.jpg b/old/50696-h/images/i115.jpg
deleted file mode 100644
index dd93307..0000000
--- a/old/50696-h/images/i115.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i117.jpg b/old/50696-h/images/i117.jpg
deleted file mode 100644
index dd6bf7f..0000000
--- a/old/50696-h/images/i117.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i118.jpg b/old/50696-h/images/i118.jpg
deleted file mode 100644
index 15e4327..0000000
--- a/old/50696-h/images/i118.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i124.jpg b/old/50696-h/images/i124.jpg
deleted file mode 100644
index b480cb8..0000000
--- a/old/50696-h/images/i124.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i125.jpg b/old/50696-h/images/i125.jpg
deleted file mode 100644
index e72b214..0000000
--- a/old/50696-h/images/i125.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i130.jpg b/old/50696-h/images/i130.jpg
deleted file mode 100644
index 44abbf2..0000000
--- a/old/50696-h/images/i130.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i132.jpg b/old/50696-h/images/i132.jpg
deleted file mode 100644
index 1bb4d0f..0000000
--- a/old/50696-h/images/i132.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i134.jpg b/old/50696-h/images/i134.jpg
deleted file mode 100644
index b97bded..0000000
--- a/old/50696-h/images/i134.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i136.jpg b/old/50696-h/images/i136.jpg
deleted file mode 100644
index 724783e..0000000
--- a/old/50696-h/images/i136.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i138.jpg b/old/50696-h/images/i138.jpg
deleted file mode 100644
index ed3d6f7..0000000
--- a/old/50696-h/images/i138.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i140.jpg b/old/50696-h/images/i140.jpg
deleted file mode 100644
index 87e29f5..0000000
--- a/old/50696-h/images/i140.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i142.jpg b/old/50696-h/images/i142.jpg
deleted file mode 100644
index 0c89e39..0000000
--- a/old/50696-h/images/i142.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i144.jpg b/old/50696-h/images/i144.jpg
deleted file mode 100644
index 9cab3d1..0000000
--- a/old/50696-h/images/i144.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i145.jpg b/old/50696-h/images/i145.jpg
deleted file mode 100644
index a6e2c80..0000000
--- a/old/50696-h/images/i145.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i146.jpg b/old/50696-h/images/i146.jpg
deleted file mode 100644
index 15464ee..0000000
--- a/old/50696-h/images/i146.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i148.jpg b/old/50696-h/images/i148.jpg
deleted file mode 100644
index c6ba821..0000000
--- a/old/50696-h/images/i148.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i150.jpg b/old/50696-h/images/i150.jpg
deleted file mode 100644
index e589702..0000000
--- a/old/50696-h/images/i150.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i152.jpg b/old/50696-h/images/i152.jpg
deleted file mode 100644
index 2cbe2a3..0000000
--- a/old/50696-h/images/i152.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i153.jpg b/old/50696-h/images/i153.jpg
deleted file mode 100644
index c6ad767..0000000
--- a/old/50696-h/images/i153.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i154.jpg b/old/50696-h/images/i154.jpg
deleted file mode 100644
index ea7b5e7..0000000
--- a/old/50696-h/images/i154.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i155.jpg b/old/50696-h/images/i155.jpg
deleted file mode 100644
index 3bfbb3d..0000000
--- a/old/50696-h/images/i155.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i156.jpg b/old/50696-h/images/i156.jpg
deleted file mode 100644
index 19c06b0..0000000
--- a/old/50696-h/images/i156.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i157.jpg b/old/50696-h/images/i157.jpg
deleted file mode 100644
index f4ea5b3..0000000
--- a/old/50696-h/images/i157.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i160.jpg b/old/50696-h/images/i160.jpg
deleted file mode 100644
index 9c23d6a..0000000
--- a/old/50696-h/images/i160.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i171.jpg b/old/50696-h/images/i171.jpg
deleted file mode 100644
index 2f0b778..0000000
--- a/old/50696-h/images/i171.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i173.jpg b/old/50696-h/images/i173.jpg
deleted file mode 100644
index 08a97fd..0000000
--- a/old/50696-h/images/i173.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i175.jpg b/old/50696-h/images/i175.jpg
deleted file mode 100644
index a7e8983..0000000
--- a/old/50696-h/images/i175.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i177.jpg b/old/50696-h/images/i177.jpg
deleted file mode 100644
index 5a0527b..0000000
--- a/old/50696-h/images/i177.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i180.jpg b/old/50696-h/images/i180.jpg
deleted file mode 100644
index 2fb1e28..0000000
--- a/old/50696-h/images/i180.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i183.jpg b/old/50696-h/images/i183.jpg
deleted file mode 100644
index fc40193..0000000
--- a/old/50696-h/images/i183.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i187.jpg b/old/50696-h/images/i187.jpg
deleted file mode 100644
index 6223fe8..0000000
--- a/old/50696-h/images/i187.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i189.jpg b/old/50696-h/images/i189.jpg
deleted file mode 100644
index 3185c4a..0000000
--- a/old/50696-h/images/i189.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i198.jpg b/old/50696-h/images/i198.jpg
deleted file mode 100644
index 7863dee..0000000
--- a/old/50696-h/images/i198.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i201.jpg b/old/50696-h/images/i201.jpg
deleted file mode 100644
index 4d3da8f..0000000
--- a/old/50696-h/images/i201.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i204.jpg b/old/50696-h/images/i204.jpg
deleted file mode 100644
index fbfeb09..0000000
--- a/old/50696-h/images/i204.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i208.jpg b/old/50696-h/images/i208.jpg
deleted file mode 100644
index fe9c3c4..0000000
--- a/old/50696-h/images/i208.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i215.jpg b/old/50696-h/images/i215.jpg
deleted file mode 100644
index ad11574..0000000
--- a/old/50696-h/images/i215.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i219.jpg b/old/50696-h/images/i219.jpg
deleted file mode 100644
index f03d1f1..0000000
--- a/old/50696-h/images/i219.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i221.jpg b/old/50696-h/images/i221.jpg
deleted file mode 100644
index 4b12178..0000000
--- a/old/50696-h/images/i221.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i226.jpg b/old/50696-h/images/i226.jpg
deleted file mode 100644
index b650810..0000000
--- a/old/50696-h/images/i226.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i232.jpg b/old/50696-h/images/i232.jpg
deleted file mode 100644
index 67beaa1..0000000
--- a/old/50696-h/images/i232.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i234.jpg b/old/50696-h/images/i234.jpg
deleted file mode 100644
index 05331dd..0000000
--- a/old/50696-h/images/i234.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i236.jpg b/old/50696-h/images/i236.jpg
deleted file mode 100644
index cadc6a5..0000000
--- a/old/50696-h/images/i236.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i238.jpg b/old/50696-h/images/i238.jpg
deleted file mode 100644
index 21b67c5..0000000
--- a/old/50696-h/images/i238.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i240.jpg b/old/50696-h/images/i240.jpg
deleted file mode 100644
index 2242d76..0000000
--- a/old/50696-h/images/i240.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i250.jpg b/old/50696-h/images/i250.jpg
deleted file mode 100644
index c4112d8..0000000
--- a/old/50696-h/images/i250.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i252.jpg b/old/50696-h/images/i252.jpg
deleted file mode 100644
index ec030d9..0000000
--- a/old/50696-h/images/i252.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i254.jpg b/old/50696-h/images/i254.jpg
deleted file mode 100644
index 6175e5a..0000000
--- a/old/50696-h/images/i254.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i255.jpg b/old/50696-h/images/i255.jpg
deleted file mode 100644
index b3bcda8..0000000
--- a/old/50696-h/images/i255.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i256.jpg b/old/50696-h/images/i256.jpg
deleted file mode 100644
index f777cb0..0000000
--- a/old/50696-h/images/i256.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i257.jpg b/old/50696-h/images/i257.jpg
deleted file mode 100644
index 8627e79..0000000
--- a/old/50696-h/images/i257.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i262.jpg b/old/50696-h/images/i262.jpg
deleted file mode 100644
index 07c1eec..0000000
--- a/old/50696-h/images/i262.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i263.jpg b/old/50696-h/images/i263.jpg
deleted file mode 100644
index 994fb75..0000000
--- a/old/50696-h/images/i263.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i265.jpg b/old/50696-h/images/i265.jpg
deleted file mode 100644
index 181360b..0000000
--- a/old/50696-h/images/i265.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i266.jpg b/old/50696-h/images/i266.jpg
deleted file mode 100644
index 1853bca..0000000
--- a/old/50696-h/images/i266.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i267.jpg b/old/50696-h/images/i267.jpg
deleted file mode 100644
index 88df6a1..0000000
--- a/old/50696-h/images/i267.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i268.jpg b/old/50696-h/images/i268.jpg
deleted file mode 100644
index 04569a0..0000000
--- a/old/50696-h/images/i268.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i269.jpg b/old/50696-h/images/i269.jpg
deleted file mode 100644
index b41388b..0000000
--- a/old/50696-h/images/i269.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i270.jpg b/old/50696-h/images/i270.jpg
deleted file mode 100644
index eb7e706..0000000
--- a/old/50696-h/images/i270.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i274.jpg b/old/50696-h/images/i274.jpg
deleted file mode 100644
index 4f21b8c..0000000
--- a/old/50696-h/images/i274.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i275.jpg b/old/50696-h/images/i275.jpg
deleted file mode 100644
index 0639635..0000000
--- a/old/50696-h/images/i275.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i276.jpg b/old/50696-h/images/i276.jpg
deleted file mode 100644
index 0d2b3bf..0000000
--- a/old/50696-h/images/i276.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i277.jpg b/old/50696-h/images/i277.jpg
deleted file mode 100644
index e2190d6..0000000
--- a/old/50696-h/images/i277.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i283.jpg b/old/50696-h/images/i283.jpg
deleted file mode 100644
index 14fd241..0000000
--- a/old/50696-h/images/i283.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i286.jpg b/old/50696-h/images/i286.jpg
deleted file mode 100644
index c320589..0000000
--- a/old/50696-h/images/i286.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i288.jpg b/old/50696-h/images/i288.jpg
deleted file mode 100644
index 776ce18..0000000
--- a/old/50696-h/images/i288.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i291.jpg b/old/50696-h/images/i291.jpg
deleted file mode 100644
index ed3d140..0000000
--- a/old/50696-h/images/i291.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i293.jpg b/old/50696-h/images/i293.jpg
deleted file mode 100644
index 7273672..0000000
--- a/old/50696-h/images/i293.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i295.jpg b/old/50696-h/images/i295.jpg
deleted file mode 100644
index 0cfa215..0000000
--- a/old/50696-h/images/i295.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i298.jpg b/old/50696-h/images/i298.jpg
deleted file mode 100644
index a8212d7..0000000
--- a/old/50696-h/images/i298.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i300.jpg b/old/50696-h/images/i300.jpg
deleted file mode 100644
index ae55188..0000000
--- a/old/50696-h/images/i300.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i305.jpg b/old/50696-h/images/i305.jpg
deleted file mode 100644
index 655ab7f..0000000
--- a/old/50696-h/images/i305.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i307.jpg b/old/50696-h/images/i307.jpg
deleted file mode 100644
index 23a403a..0000000
--- a/old/50696-h/images/i307.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i308.jpg b/old/50696-h/images/i308.jpg
deleted file mode 100644
index 2e74057..0000000
--- a/old/50696-h/images/i308.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i310.jpg b/old/50696-h/images/i310.jpg
deleted file mode 100644
index 27b102d..0000000
--- a/old/50696-h/images/i310.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i311.jpg b/old/50696-h/images/i311.jpg
deleted file mode 100644
index 669f7b1..0000000
--- a/old/50696-h/images/i311.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i317.jpg b/old/50696-h/images/i317.jpg
deleted file mode 100644
index 82a3146..0000000
--- a/old/50696-h/images/i317.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i320.jpg b/old/50696-h/images/i320.jpg
deleted file mode 100644
index 3709939..0000000
--- a/old/50696-h/images/i320.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i324.jpg b/old/50696-h/images/i324.jpg
deleted file mode 100644
index ca7c879..0000000
--- a/old/50696-h/images/i324.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i329.jpg b/old/50696-h/images/i329.jpg
deleted file mode 100644
index d25329b..0000000
--- a/old/50696-h/images/i329.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i331.jpg b/old/50696-h/images/i331.jpg
deleted file mode 100644
index ae94878..0000000
--- a/old/50696-h/images/i331.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i337.jpg b/old/50696-h/images/i337.jpg
deleted file mode 100644
index 15bdb8e..0000000
--- a/old/50696-h/images/i337.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i340.jpg b/old/50696-h/images/i340.jpg
deleted file mode 100644
index 0c04c00..0000000
--- a/old/50696-h/images/i340.jpg
+++ /dev/null
diff --git a/old/50696-h/images/i345.jpg b/old/50696-h/images/i345.jpg
deleted file mode 100644
index cd62718..0000000
--- a/old/50696-h/images/i345.jpg
+++ /dev/null
diff --git a/old/50696-h/images/logo.jpg b/old/50696-h/images/logo.jpg
deleted file mode 100644
index 852e2f7..0000000
--- a/old/50696-h/images/logo.jpg
+++ /dev/null