diff options
Diffstat (limited to '41210.txt')
| -rw-r--r-- | 41210.txt | 24001 |
1 files changed, 0 insertions, 24001 deletions
diff --git a/41210.txt b/41210.txt deleted file mode 100644 index 54b481a..0000000 --- a/41210.txt +++ /dev/null @@ -1,24001 +0,0 @@ -The Project Gutenberg EBook of The life of Isambard Kingdom Brunel, Civil -Engineer, by Isambard Brunel - -This eBook is for the use of anyone anywhere 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/license - - -Title: The life of Isambard Kingdom Brunel, Civil Engineer - -Author: Isambard Brunel - -Release Date: October 28, 2012 [EBook #41210] - -Language: English - -Character set encoding: ASCII - -*** START OF THIS PROJECT GUTENBERG EBOOK THE LIFE OF I K BRUNEL *** - - - - -Produced by Chuck Greif and the Online Distributed -Proofreading Team at http://www.pgdp.net (This file was -produced from images available at The Internet Archive) - - - - - - - -[Illustration: IK Brunel Signature - -Painted by J. C. Horsley, R.A.--Engraved by T. O. Barlow.] - - - - -THE LIFE -OF -ISAMBARD KINGDOM BRUNEL, -CIVIL ENGINEER. - -BY - -ISAMBARD BRUNEL, B.C.L., -OF LINCOLN'S INN; -CHANCELLOR OF THE DIOCESE OF ELY. - -LONDON: -LONGMANS, GREEN, AND CO. -1870. - - - - -PREFACE. - - -I have not attempted to describe the events of my father's life in -chronological order beyond the end of Chapter III., which brings down -the narrative to the close of 1835, the year in which the Act was -obtained for the Great Western Railway. - -Chapter IV. contains a general account of my father's railway works, -with the exception of the Bridges, which are described in Chapter VII. -The history of the Broad Gauge and of the trial of the Atmospheric -System on the South Devon Railway is given in Chapters V. and VI. - -Chapters VIII.--XIII. contain an account of my father's labours for the -advancement of Ocean Steam Navigation. It will be noted that these -chapters cover the same period as Chapters IV.--VII., namely, from 1835, -the year of the commencement of the Great Western Railway and the 'Great -Western' Steam-ship, to 1859, the year of his death, in which the -Saltash Bridge and the 'Great Eastern' were both completed. - -Chapters VII. (on the Bridges) and XIV. (on the Docks) have been written -by Mr. William Bell, for many years a member of my father's engineering -staff; and in regard to Chapter V. (on the Broad Gauge), I have to -acknowledge assistance rendered me by Mr. William Pole, F.R.S. - -For the Note on the Carbonic Acid Gas Engine which follows Chapter I., I -am indebted to Mr. William Hawes; and for Chapter VI. (on the -Atmospheric System) to Mr. Froude, F.R.S. - -I have also printed letters, written to me at my request, relating to -various incidents in my father's life. - -The assistance I received in the preparation of the chapters on Steam -Navigation from my friend the late Captain Claxton, R.N., has been -referred to in the note to p. 234. - -I have throughout availed myself of my brother's professional knowledge. - -I have been compelled, in order to bring the work within the compass of -a single volume, to omit much that would otherwise have been inserted, -and I must therefore be held responsible for the general arrangement of -those parts which have been contributed by others, as well as for the -chapters which I have written myself. - -Lastly, I desire gratefully to thank those friends who, by supplying me -with materials and revising the proof sheets, have helped me in my -endeavour to make this book, as far as possible, an accurate record of -my father's life, written in the spirit of which he would have approved. - -I. B. - -18 DUKE STREET, WESTMINSTER: - -_November_, 1870. - - - - -CONTENTS. - -PAGE - -LIST OF REPORTS AND OTHER ORIGINAL DOCUMENTS xvii - -LIST OF ILLUSTRATIONS xxvii - - -CHAPTER I. - -_EARLY LIFE._ - -A.D. 1806--1828. - -Birth of Mr. Brunel, April 9, 1806--Sir Marc Isambard Brunel--The Block -Machinery--Mr. Brunel's School Life--The Thames Tunnel--Sinking of the -Rotherhithe Shaft--Description of the Shield--Extracts from Sir Isambard -Brunel's Journals from the Commencement of the Thames Tunnel to the date -of the Second Irruption of the River, January 12, 1828--_Note A_: The -Bourbon Suspension Bridges--_Note B_: Experiments with Carbonic Acid -Gas......1 - - -CHAPTER II. - -_THE CLIFTON SUSPENSION BRIDGE._ - -A.D. 1829--1853. AETATIS 24--48. - -Origin of the Undertaking--The First Competition, November -1829--Description of Mr. Brunel's Plans--Mr. Telford's Decision as -Umpire--Mr. Telford's Design--The Second Competition--Mr. Brunel -appointed Engineer, March 1831--Commencement of the Works, August -1836--Description of the Design--Abandonment of the Works, -1853--Formation of a New Company and Completion of the Bridge, -1864--_Note_: The Hungerford Suspension Bridge.....46 - - -CHAPTER III. - -_EARLY HISTORY OF THE GREAT WESTERN RAILWAY._ - -A.D. 1833--1835. AETATIS 27--30. - -Sketch of the History of Railways in England prior to 1833--The Stockton -and Darlington--The Liverpool and Manchester--The London and -Birmingham--Proposed Railway between London and Bristol--Mr. Brunel -appointed Engineer, March 7, 1833--Survey of the Line--Unsuccessful -Application to Parliament in 1834--Successful Application in -1835--Reminiscences of Mr. Brunel, 1833-1835--Extract from Mr. Brunel's -Diary, written at the close of 1835.....61 - - -CHAPTER IV. - -_RAILWAY WORKS._ - -A.D. 1835--1859. AETATIS 30--54. - -Construction of the Great Western Railway--The Box Tunnel--The Bath and -Bristol Stations--The Paddington Station--The Great Western -Hotel--Branches and Extensions of the Great Western Railway--The Bristol -and Exeter Railway--Railways in Devonshire and Cornwall--Railways to -Basingstoke, to Weymouth, and to Salisbury--In South Wales--In -Ireland--In Italy--In India--Supervision of Works--Mr. Brunel's -Engineering Staff--His Reputation as a Witness--Reminiscences of Mr. -Brunel, 1835-1838.....79 - - -CHAPTER V. - -_THE BROAD GAUGE._ - -Origin of the Ordinary Gauge of Railways--Adoption by Mr. Brunel of the -Broad Gauge on the Great Western Railway--Reasons for its Adoption--The -Permanent Way--Reports of Mr. Nicholas Wood and Mr. John Hawkshaw, -1838--_Extract from Report of Directors of Great Western Railway -Company_ (December 20, 1838)--Extension of the Broad Gauge System--Break -of Gauge--Royal Commission on the Gauge of Railways, 1845--_Letter of -Mr. Brunel on the Broad Gauge_ (August 6, 1845)--Gauge Act of 1846--The -Mixed Gauge--Report of Railway Commissioners, 1847--Northern Extensions -of the Great Western Railway--Advantages of the Broad Gauge--Partial -Abandonment of the Broad Gauge.....99 - - -CHAPTER VI. - -_THE ATMOSPHERIC SYSTEM._ - -A.D. 1840--1848. AETATIS 35--43. - -Preliminary Observations--The South Devon Railway--Description of the -Atmospheric System--History of its Introduction prior to 1844--_Report -by Mr. Brunel, recommending its Adoption on the South Devon Railway_ -(August 19, 1844)--Examination of this Report--Mr. Brunel's Evidence -before the Select Committee on Atmospheric Railways, 1845--History of -the Application of the System on the South Devon Railway, -1844-1848--_Report on State of Works_ (August 28, 1847)--_Report on -Causes of Failure_ (August 19, 1848)--Abandonment of the System, -September 1848--_Note_: Comparison of Stationary and Locomotive -Power.....131 - - -CHAPTER VII. - -_RAILWAY BRIDGES AND VIADUCTS._ - -1. Brickwork and Masonry Bridges--Hanwell Viaduct--Maidenhead -Bridge--Flying Bridges--_Letter from Mr. Brunel on Bridge Construction_ -(December 30, 1854)--2. Timber Bridges--Sonning Bridge--Bath -Bridge--Stonehouse Viaduct--Bourne Viaduct--St. Mary's Viaduct--Viaducts -on the South Devon Railway--Ivy-bridge--Viaducts on the South Wales -Railway--Newport--Landore--Viaducts on the Cornwall Railway--St. -Pinnock--Viaducts on the West Cornwall and Tavistock -Railways--Preservation of Timber--3. Cast-iron Bridges--_Letter on Use -of Cast Iron_ (April 18, 1849)--Hanwell Bridge--Experiments on Cast-iron -Girders--_Extract from Letter to Secretary of Commission on Application -of Iron to Railway Structures_ (March 13, 1848)--4. Wrought-iron -Bridges--Girder Bridges--Experiments on Wrought-iron Girder--Opening -Bridges--Trussed Bridges--Newport Viaduct--Windsor Bridge--Chepstow -Bridge--Method of Sinking the Cylinders--Description of the Main -Truss--The Floating Operations--The Royal Albert Bridge at Saltash--The -Centre Pier--Description of the Superstructure--The Floating and Raising -of the Trusses--Opening of the Bridge by H. R. H. the Prince -Consort--_Note_: Experiments on Matters connected with Bridge -Construction.....171 - - -CHAPTER VIII. - -_STEAM NAVIGATION. THE 'GREAT WESTERN' STEAM-SHIP._ - -A D. 1835--1847. AETATIS 30--42. - -Introduction to the Chapters on Steam Navigation--Formation of the Great -Western Steam-Ship Company--Commencement of the Building of the 'Great -Western'--_Report on Selection of the Builders of the Engines_ (June 18, -1836)--Statements of Dr. Lardner on the probable Failure of a line of -Steam-ships between England and America--Voyage of the 'Great Western' -to London--Completion of the Engines--Her return to Bristol--Fire on -Board, and Accident to Mr. Brunel--Voyage to New York--Comparison -between the Performances of the 'Great Western' and the -'Sirius'--Subsequent History of the 'Great Western'--_Note_: Dimensions -of the Ship and Engines.....231 - - -CHAPTER IX. - -_STEAM NAVIGATION. THE 'GREAT BRITAIN' STEAM-SHIP._ - -A.D. 1838--1847. AETATIS 33--42. - -Commencement of the building of the 'Great Britain'--_Report on the -Engines_ (June 13, 1839)--Experiments on the Screw Propeller--Its -Adoption in the 'Great Britain'--Completion of the Ship--Her Voyage -across the Atlantic--Stranding of the 'Great Britain' in Dundrum -Bay--_Letter to Captain Claxton on the Condition of the 'Great Britain' -and on the Means to be adopted for saving her_ (December 10, -1846)--_Report to the Directors on the same Subject_ (December 14, -1846)--Appointment of Captain Claxton to superintend the Execution of -Mr. Brunel's Plans--_Letter to Captain Claxton on the Difficulties to be -overcome_ (December 29, 1846)--_Report enclosing Captain Claxton's -Account of the Erection of the Breakwater_ (February 27, 1847)--_Report -on the Arrangements for Floating off the Ship_ (May 4, 1847)--Successful -Accomplishment of the Floating Operations--Subsequent History of the -'Great Britain'--_Note_: Dimensions of the Ship and Engines.....246 - - -CHAPTER X. - -_STEAM NAVIGATION. INTRODUCTION OF THE SCREW PROPELLER INTO THE ROYAL -NAVY._ - -A.D. 1841--1844. AETATIS 36--39. - -Appointment of Mr. Brunel to conduct Experiments for the Admiralty with -various Forms of the Screw Propeller, April 1841--Trials with the -'Polyphemus'--Opposition to Mr. Brunel's Experiments--Trials with the -'Rattler', October 1843--October 1844.....283 - - -CHAPTER XI. - -_STEAM NAVIGATION. THE 'GREAT EASTERN' STEAM-SHIP, FROM THE COMMENCEMENT -OF THE UNDERTAKING TO THE LAUNCH._ - -A.D. 1851--1857. AETATIS 46-52. - -Introductory Observations--The Australian Steam Navigation -Company--_Statement of Mr. Brunel's Project of a Line of large Ships_ -(June 10, 1852)--Adoption of his Plans by the Eastern Steam Navigation -Company--_Extract from a Letter describing the Scheme_ (July 1, -1852)--_Letter to J. Scott Russell, Esq., on the Form and Dimensions of -the Great Ship_ (July 13, 1852)--_Report on Mode of Proceeding_ (July -21, 1852)--_Report on Enquiries Relating to the Draught and Form of the -Vessel_ (October 6, 1852)--_Report on the Proceedings of the Committee -appointed to consider Mr. Brunel's Plans_ (March 21, 1853)--Tenders -invited for the Ship and Engines--_Report on Tenders_ (May 18, -1853)--Preparation of the Contracts and Specifications--_Extracts from -Mr. Brunel's Memoranda_ (A.D. 1852, 1853, 1854)--_Letter on his Position -and Duties as Engineer of the Company_ (August 16, 1854)--_Letter on an -Article in a Newspaper_ (November 16, 1854)--_Report on the Undertaking_ -(February 5, 1855)--Arrangements proposed for obtaining Astronomical -Observations--_Letter to G. B. Airy, Esq., Astronomer Royal_ (October 5, -1852)--Appointment of Mr. William Harrison to the Command of the -Ship--_Memorandum on the Management of the Great Ship_ (October -1855)--_Letter on the Duties of the Chief Engineer_ (March 19, -1857)--Suspension and Resumption of the Works.....289 - - -CHAPTER XII. - -_STEAM NAVIGATION. THE 'GREAT EASTERN' STEAM-SHIP. THE LAUNCH._ - -A.D. 1857, 1858. AETATIS 52. - -Determination that the Ship should be launched broadside to the -River--And that the Launch should be slow--_Extracts from Mr. Brunel's -Report of February 1855_--Reasons for the Adoption of Iron Sliding -Surfaces--Description of the Ways and Cradles--And of the Motive Power -provided for launching the Ship--_Memorandum on proposed Arrangements -for the Launch_ (September 26, 1857)--_Letter to Captain Harrison on -River Tackle_ (September 30, 1857)--_Letter on the Nature of the -Operations_ (October 23, 1857)--_Memorandum on general Arrangements and -intended Mode of Proceeding_ (October 30, 1857)--History of the Launch, -Nov. 3, 1857 to January 31, 1858--_Letter to the Directors_ (November -26, 1857)--_Report and Memorandum on the Launching Operations_ (December -17, 1857)--Floating the Ship--_Note A_: Experiments and Observations on -Friction--_Note B:_ Letter to W. Froude, Esq. (February 2, 1858).....340 - - -CHAPTER XIII. - -_STEAM NAVIGATION. THE 'GREAT EASTERN' STEAM-SHIP. COMPLETION AND -SUBSEQUENT HISTORY._ - -A.D. 1858, 1859. AETATIS 52-54. - -A.D. 1859-1870. - -Preparations for completing the Ship--Formation of the Great Ship -Company--Mr. Brunel's Absence from England--Progress of the Works from -his Return to his last Illness--Voyage to Weymouth--Explosion of -Water-Heater--Storm at Holyhead--Description of the Ship--Her first -Voyage to New York, June 1860--Second Voyage to New York, May -1861--Voyage with Troops to Quebec, June 1861--Fracture of Rudder Head -and Destruction of Paddlewheels, September 1861--Voyages in -1862--Accident off Montauk Point, August 27, 1862--Voyages in -1863--Formation of the Great Eastern Steam-Ship Company--Remarks on the -History of the 'Great Eastern' previous to her Employment in laying -Submarine Telegraph Cables--Telegraph Expeditions of 1865 and -1866--French Cable Expedition of 1869--Voyage to Bombay and Aden, 1869, -1870--Concluding Remarks--_Note_: Dimensions of the Ship and -Engines.....392 - - -CHAPTER XIV. - -_DOCK AND PIER WORKS._ - -A.D. 1831--1859. AETATIS 26--54. - -Monkwearmouth Docks, 1831--Bristol Docks--Floating Harbour, -1832--Proposed Works at Portishead--New Lock at Bristol, 1845--Bristol -Dock Gates--Plymouth Great Western Docks, 1847--Briton Ferry Docks, -1851--Brentford Dock, 1856--Pier at Milford Haven, 1857.....417 - - -CHAPTER XV. - -_MISCELLANEOUS WORKS._ - -The Great Exhibition of 1851--The Crystal Palace Water Towers, -1853--Polygonal Rifle, 1852--Gunnery Experiments, 1854--Floating -Gun-Carriage, 1854--Renkioi Hospital Buildings, 1855.....445 - - -CHAPTER XVI. - -_MR. BRUNEL'S PROFESSIONAL OPINIONS AND PRACTICE._ - -Scheme of the Chapter--Mr. Brunel's Position in relation to the -Companies of which he was Engineer--_Letter on the Direction of Railway -Works in Italy_ (March 4, 1845)--_Letter on the Position of Joint -Engineer_ (October 16, 1843)--_Letter on the Position of Consulting -Engineer_ (December 30, 1851)--_Letter on the Position of the Engineer -in relation to the Contractors_ (May 26, 1854)--_Letters on the Position -of the Engineer in relation to the Directors_ (April 15, 1850, December -6, 1851, January 22, 1857)--Mr. Brunel's Assistants--_Letters on -Interference of Directors with the Assistant Engineers_ (January 19, -1842, January 28, 1842, January 12, 1851)--Mr. Brunel's Pupils--His -Relations with other Engineers--Inventors--_Letter in reply to an -Inventor_ (September 17, 1847)--Mr. Brunel's Views as to State -Interference--_Letter on the Royal Commission on the Application of Iron -to Railway Structures_ (March 13, 1848)--_Letter on a Proposal to obtain -the Recognition in England of Decorations conferred at the Paris -Exhibition of 1855_ (February 9, 1856)--Mr. Brunel's Opinion on the -Patent Laws--_Memorandum for Evidence before the Select Committee of the -House of Lords on the Patent Laws, 1851_--_Extract from Observations on -the Patent Laws, made by Mr. Brunel at a Meeting of the Society of -Arts,_ March 26, 1856.....474 - - -CHAPTER XVII. - -_PRIVATE LIFE._ - -Reminiscences of Mr. Brunel's Private Life--Removal to 18 Duke Street, -Westminster--His Marriage, 1836--Special Constable in 1848--Mr. Brunel's -Love of Art--His Journey to Italy, 1842--Accident with the -Half-Sovereign, 1843--Purchase of Property in Devonshire, 1847--His life -at Watcombe--The Launch of the 'Great Eastern,' 1857--Mr. Brunel's -Failing Health--Journeys to Switzerland and Egypt, 1858--_Letter from -Philae_ (February 12, 1859)--His last Illness--His Death, September 15, -1859--Funeral--Address of Joseph Locke, Esq., M.P., at the Institution -of Civil Engineers, November 8, 1859.....499 - - -APPENDIX I. - -Report to the Directors of the Great Western Railway on the Broad Gauge, -&c. (August 1838).....525 - - -APPENDIX II. - -Report to the Directors of the Great Western Steam-Ship Company, -recommending the Adoption of the Screw Propeller in the 'Great Britain' -Steam-ship (October 1840).....539 - - -INDEX.....559 - - - - -LIST - -OF - -REPORTS AND OTHER ORIGINAL DOCUMENTS. - - - PAGE -1. Extract from Mr. Brunel's Diary (December 26, 1835).....78 - -2. Letter on the Box Tunnel (June 21, 1842).....81 - -3. Extract from Report to Directors of the Great Western Railway Company -on Break of Gauge (December 13, 1838).....105 - -4. Extract from Report to Directors of the Great Western Railway Company -on the Permanent Way (February 1837).....109 - -5. Letter on various Points relating to the Broad Gauge (August 4, -1845).....120 - -6. Extract from Letter on Atmospheric System (April 8, 1844).....137 - -7. Report to the Directors of the South Devon Railway Company, -recommending them to adopt the Atmospheric System (August 19, -1844).....138 - -The question had been frequently considered by him (p. 138)--Stationary -power is cheaper and otherwise better than locomotive power (p. -138)--The Atmospheric System is a good, economical mode of applying -stationary power (p. 138)--Reasons for considering it applicable to the -South Devon Railway (p. 139)--In the construction of the line (p. -140)--In the subsequent working (p. 141). - -8, 9. Letters on giving Evidence before the Select Committee of the -House of Commons on the Atmospheric System (March 31, 1845; April 3, -1845).....145 - -10. Report to the Directors of the South Devon Railway on the State of -the Atmospheric Apparatus (August 27, 1847).....149 - -Regret at postponement of working (p. 149)--Which has been caused by -delay in completion of the engines (p. 149)--Experimental trains have -run (p. 149)--Difficulties have exceeded all just anticipations (p. -150). - -11. Report to a Committee of the Directors of the South Devon Railway -Company on the Causes of the Failure of the Atmospheric System (August -19, 1848).....159 - -The first difficulty has been in the stationary engines, which have -consumed an excessive amount of fuel (p. 159)--The difficulties in the -working of the longitudinal valve have been more numerous (p. 161)--The -principal evil might be remedied in a new valve (p. 162)--An extension -of the system beyond Newton cannot be recommended (p. 162)--The delay in -obtaining the telegraph has been a great disappointment (p. 163). - -12. Letter on the Design of Engineering Works (December 30, -1854).....178 - -13. Extract from Letter on the Use of Cast Iron in Bridge Construction -(April 18, 1849).....190 - -14. Extract from Letter on the same Subject (March 13, 1848).....192 - -15, 16, 17. Extract from Letters on Bridges of Large Spans (January 31, -1852; December 1, 1852; May 30, 1854).....212 - -18. Extract from Report on the Cornwall Railway as to making the Saltash -Bridge for a Single Line (February 5, 1852).....214 - -19. Report to the Directors of the Great Western Steam-Ship Company on -the Selection of the Builders of the Engines for the 'Great Western' -Steam-ship (June 18, 1836).....235 - -Every means must be taken to secure the best engines possible in this -the boldest attempt yet made (p. 235)--The peculiar conditions required -in these engines (p. 235)--They must, as far as is possible, be perfect -in all their details from the moment of their completion (p. 235)--The -machinery required is by no means an ordinary steam-engine (p. -236)--Modifications necessary in designing engines of so large a size -(p. 236)--Reasons based on these considerations for preferring Messrs. -Maudslay and Field as builders of these engines (p. 236). - -20. Letter on the Engines for the 'Great Britain' Steam-ship (June 12, -1839).....249 - -Both the plans of Messrs. Maudslay and Field and Mr. Humphrys are -adapted to the case, and the choice will depend upon the relative cost -and advantages of forming an establishment to build the engines, and -that of having the skill of experienced manufacturers (p. 249). - -21. Letter to T. R. Guppy, Esq., on the Construction of Iron Ships -(August 3, 1843).....259 - -22. Extract from Letter on the 'Great Britain' Steam-ship (December 11, -1844).....261 - -23. Letter to Captain Claxton on the State of the 'Great Britain' -Steam-ship (December 10, 1846).....264 - -24. Report on the Condition of the 'Great Britain' Steam-ship when -stranded in Dundrum Bay (December 14, 1846).....267 - -The ship is, apart from mere local damage, perfectly sound, which would -not have been the case had she been built of timber (p. -267)--Description of her injuries (p. 268)--Consideration of the best -means of recovering the property invested in her--It would not be -profitable to break her up (p. 268)--How, then, is the vessel to be got -into port? (p. 269)--This question is secondary to that of how she is to -be preserved until she can be removed (p. 269)--A stiff timber -breakwater would not stand, even if it could be safely constructed (p. -269)--The best plan is to form under the stern and along the exposed -side of the ship a mass of fagots (p. 270)--And in order to preserve the -ship, this must be done without delay (p. 270)--As to floating her off, -she should be lifted and made water-tight (p. 271)--But she must first -be preserved (p. 272). - -25. Letter to Captain Claxton on the Breakwater (December 29, -1846).....272 - -26. Report enclosing Captain Claxton's Account of the Proceedings at -Dundrum (February 27, 1847).....273 - -Success achieved by Captain Claxton in constructing the breakwater of -fagots (p. 273)--Introduction by him of several important alterations -and improvements in the plans proposed (p. 274). - -27. Report on the proposed Means of Floating the 'Great Britain' -Steam-ship (May 4, 1847).....278 - -The ship has been successfully protected and lifted, and made -water-tight, so that the operation of floating by camels becomes more -practicable (p. 279)--The Directors would do well to call in Mr. Bremner -to advise them (p. 280). - -28. Extract from Letter relating to Proceedings at the Admiralty as to -the Screw Propeller (July 8, 1842).....283 - -29. Extract from Letter on the same Subject (August 6, 1842).....286 - -30. Statement of Project for a Line of large Steam-ships (June 10, -1852).....292 - -The principle advocated is that of making the vessel large enough to -carry her own coal for the voyage, just as the 'Great Western' -steam-ship did in 1838 (p. 292)--The size being limited only by the -extent of demand for freight, and by the circumstances of the ports to -be frequented (p. 292). - -31. Extract from Letter describing the Project of the Great Ship (July -1, 1852).....293 - -32. Letter to J. Scott Russell, Esq., on the Form and Dimensions of the -Great Ship (July 13, 1852).....294 - -33. Report to the Directors of the Eastern Steam Navigation Company on -mode of Proceeding (July 21, 1852).....296 - -34. Report on Enquiries relating to the Draught and Form of the Great -Ship (October 6, 1852).....297 - -35. Report on the Dimensions of the Great Ship (March 21, 1853).....299 - -36. Report on the Tenders for the Ship and Engines (May 18, -1853).....301 - -A short specification was drawn up for the engines, and detailed -drawings and specifications for the ship (p. 301)--Tenders have been -received for the engines from Mr. J. Scott Russell, Messrs. Watt and -Co., and Mr. Humphrys (p. 302)--After frequent communications with these -gentlemen, Messrs. Watt and Co.'s designs are preferred for the screw -engines, which will be the largest yet made, and on which will mainly -depend the performances of the ship (p. 302), and Mr. J. Scott Russell's -for the paddle engines (p. 302)--As regards a tender for the ship, after -communications with several parties, the result is a tender from Mr. J. -Scott Russell (p. 303). - -37. Extracts from Mr. Brunel's Memoranda relating to the 'Great Eastern' -Steam-ship (July 11, 1852, to November 18, 1853).....304 - -July 11, 1852: Dimensions of the ship (p. 304)--Division of power -between the screw and paddle engines (p. 305)--Every known means must be -adopted to ensure efficiency (p. 305)--Jacketing of steam pipes, &c. (p. -305). July 17, 1852: Conference with Mr. Field as to division of power -between the screw and paddle engines (p. 305)--Pressure of steam (p. -305)--Nothing uncertain must be risked (p. 305)--Jacketing (p. 305). -July 19, 1852: Strong bulkheads every 30 feet or thereabouts, and the -main ribs, and even at least two main deck beams, to be longitudinal, -instead of transverse (p. 305). February 2, 1853: Present views as to -the construction of the ship and engines (p. 306)--Boilers (p. -307)--Advantages of oscillating engines for both screw and paddle -engines (p. 307). February 21, 1853: Proper dimensions for the Calcutta -line (p. 308)--Gas (p. 308)--Ventilation (p. 308)--Steering (p. 308). -March 14, 1853: Dimensions now determined on (p. 308). March 22, 1853: -Various dimensions settled (p. 308). April 28, 1853: Tenders are being -sought for (p. 308)--Arrangements for measuring the coal (p. 309)--Use -of clean water (p. 309). August 7, 1853: Memoranda for engines (p. 309). -November 18, 1853: Governors (p. 309)--Auxiliary engine and boiler (p. -309). - -38. Extracts from Mr. Brunel's Memoranda relating to the 'Great Eastern' -Steam-ship (February 25 to March 10, 1854).....310 - -February 25, 1854: Thought and labour involved in the details of the -construction both of the ship and engines (p. 310)--Cabin arrangements -(p. 310)--Economy of material in the construction of the ship (p. -310)--A matter generally neglected in shipbuilding (p. 310)--All this -misconstruction forbidden (p. 311). March 3, 1854: Details of screw -engines (p. 311). March 10, 1854: Details of ship (p. 311). - -39. Letter to the Secretary of the Eastern Steam Navigation Company, on -Position as Engineer of the Company (August 16, 1854).....311 - -His unusual stake in the undertaking, and the heavy responsibility he -has incurred (p. 311)--The work is one which requires that it should be -entirely under his individual management and control (p. 312)--And -therefore there must be no other adviser or source of information on any -question connected with the construction or mode of carrying out the -work (p. 312). - -40. Letter to the same on an Article in a Newspaper (November 16, -1854).....313 - -His general rule is not to notice newspaper articles, but this one bears -the stamp of authority (p. 313)--Marked care is shown in depreciating -his former efforts in advancing steam navigation, and in representing -him, in the present case, as the passive approver of the project of -another (p. 313)--Whereas it originated solely with him, and has been -worked out by him with great thought and labour (p. 314). - -41. Report to the Directors of the Eastern Steam Navigation Company, -describing the Nature of the Undertaking (February 5, 1855).....315 - -Labour of preparing the preliminary designs for the ship (p. -316)--[Proposed arrangements for launching]--Principal peculiarities in -the construction of the ship (p. 316)--Water-tight compartments (p. -316)--Transverse bulkheads (p. 316)--Double skin (p. 317)--Longitudinal -bulkheads (p. 318)--Economy in materials (p. 318)--Engines (p. -318)--Boilers (p. 319)--The best advice has been sought on every point -(p. 319)--The position and design of the paddlewheels (p. 319)--The -screw propeller--(p. 320)--Protection from fire (p. 320)--Masts and -sails (p. 320)--Astronomical observations (p. 320)--Lightning conductors -(p. 321)--Adjustment of compasses (p. 321). - -42. Letter to G. B. Airy, Esq., Astronomer Royal (October 5, -1852).....321 - -As so much depends on perfect navigation, every means is to be taken to -ensure a constant determination of the ship's position and course (p. -321)--It is proposed to have an observatory and staff of observers to be -constantly engaged in taking observations (p. 322)--What should be the -nature of these observations and of the instruments required? (p. 322). - -43. Memorandum on the Management of the Great Ship (October -1855).....324 - -The principles to be followed in the use of this new machine, and the -qualifications of the commander, have long been a subject of anxious -consideration by him (p. 324)--This ship requires a totally different -management from that suited to ordinary vessels (p. 325)--Examples of -this proposition (p. 326)--Size of the great ship (p. 326)--By no -possibility must she be allowed to touch the ground (p. 327)--Probable -effects of the great size and mass of this vessel (p. 329)--And of her -speed (p. 330)--The proposed system of continuous observation (p. -330)--The exact course the ship is to take must be determined previously -to the voyage, and must be strictly adhered to (p. 331)--Economy of fuel -another consideration of the highest importance (p. 332)--Proper speed -of the engines (p. 332)--Use of the sails (p. 333)--Peculiarities of the -position of the commander (p. 333)--His attention must be devoted -exclusively to the general management of the system by which the ship is -to be made to go like a piece of machinery (p. 333)--His assistants (p. -334)--Four chief officers (p. 334)--A master at the head of a staff of -observers, who are to make continuous observations upon the position and -performances of the ship (p. 334)--The chief engineer (p. 335)--The -principles herein set out are to be adopted by the commander as the -guide of his conduct in working this machine (p. 335). - -44. Letter on the Responsibility of his Position (sent with -last).....324 - -45. Letter on the Duties of the Chief Engineer of the Great Ship (March -19, 1857).....335 - -The success of the ship as a steamboat will depend entirely upon the -amount of power developed by the engines in proportion to the fuel -consumed (p. 336)--The peculiar duties of the chief engineer will be to -obtain the largest amount of steam from the defined expenditure of fuel, -and the use of this steam so as to obtain the largest amount of power -and the largest amount of result (p. 337)--Accurate measurements -required of fuel expended and results obtained (p. 337)--Economy in -every department may make the difference between the success and failure -of the ship (p. 337)--The chief engineer should, if possible, -superintend the erection of the engines (p. 338). - -46. Extract from Report to the Directors of the Eastern Steam Navigation -Company, describing the proposed Arrangements for Launching (February 5, -1855).....341 - -Reasons for deciding to launch the ship sideways (p. 341)--And probably -gradually (p. 342). - -47. Extract from Memorandum as to Power required to move the Ship -(September 26, 1857).....352 - -48. Letter to Captain Harrison on the River Tackle (September 30, -1857).....354 - -49. Letter to the Directors of the Eastern Steam Navigation Company on -the Nature of the Launching Operations (October 23, 1857).....355 - -The date is uncertain (p. 355)--The ship is to be lowered down and -floated off by a slow and laborious operation (p. 355)--She may stop or -not move at all (p. 356). - -50. Memorandum on General Arrangements and intended Mode of Proceeding -in the Launching Operations (October 30, 1857).....356 - -51. Letter to the Directors of the Eastern Steam Navigation Company on -the State of the Operations (November 26, 1857).....366 - -52. Letter to the Directors, and Memorandum on the State of the -Operations (December 17, 1857).....377 - -53. Letter to W. Froude, Esq., describing the Floating of the 'Great -Eastern' (February 2, 1858).....389 - -54. Extract from Report to the Directors of the Bristol Dock Company on -the Condition of the Floating Harbour (August 31, 1832).....423 - -55. Extract from Report on the same subject (January 31, 1842).....424 - -56. Extract from Report on Portishead Pier (December 26, 1839).....427 - -57. Letter on the Distribution of Prizes, addressed to the Chairman of -the Committee of the Section of Machinery of the Exhibition of 1851 -(March 11, 1850).....445 - -58. Extract from Report of the Jury of Class VII. of the Exhibition of -1851 on Sir Joseph Paxton's Design for the Building.....447 - -59, 60, 61. Letters to Westley Richards, Esq., on the Polygonal Rifle -(October 25, 1852; February 7, 1853; November 26, 1858).....450-1 - -62. Extract from Letter to James Nasmyth, Esq., on the Construction of -Large Guns (April 2, 1855).....452 - -63. Extract from Letter to W. G. Armstrong, Esq., on the Wire Gun (June -8, 1855).....454 - -64. Memorandum on the Floating Gun-Carriage (December 20, 1855).....455 - -The principle is fixing a very heavy gun in a floating shot-proof -chamber (p. 455)--Mode of working the gun (p. 455)--Mode of manoeuvring -the vessel (p. 456)--Mode of attacking the Baltic forts with a fleet of -such vessels (p. 457)--Thickness of iron required to make the vessel -shot proof (p. 458)--Best manner of constructing the vessels (p. 458). - -65. Letter to the Secretary of the Admiralty on the Floating -Gun-Carriage (July 27, 1855).....459 - -66. Memorandum on Renkioi Hospital Buildings (March 1855).....463 - -Necessary conditions in designing these buildings (p. 463)--General -description of them (p. 463)--Closets and lavatories (p. 464)--External -and internal covering (p. 464)--Ventilation (p. 464)--Kitchens (p. -465)--Drainage (p. 466)--Officers' quarters (p. 466)--Transport of -materials (p. 466)--Portable baths (p. 467)--Cost of buildings (p. -467). - -67. Letter on the Direction of Railway Works (March 4, 1845).....475 - -68. Letter on the Position of Joint Engineer (October 16, 1843).....476 - -69. Letter on the Position of Consulting Engineer (December 30, -1851).....477 - -70. Letter on the Position of the Engineer in relation to the -Contractors (May 26, 1854).....477 - -71, 72, 73. Extracts from Letters on the Relations between the Engineer -and the Directors (April 15, 1850; December 6, 1851; Jan. 22, -1857).....478-481 - -74, 75, 76. Extracts from Letters on Interference of Directors with the -Assistant Engineers (January 19, 1842; January 28, 1842; December 12, -1851).....481-3 - -77. Extract from Diary (May 5, 1846).....485 - -78. Letter to an Inventor (September 17, 1847).....486 - -79. Letter on the Royal Commission on the Application of Iron to Railway -Structures (March 13, 1848).....486 - -80. Letter on a Proposal to obtain Recognition in England of Decorations -conferred at the Paris Exhibition of 1855 (Feb. 9, 1856).....489 - -81. Memorandum for Evidence before the Select Committee of the House of -Lords on the Patent Laws, A.D. 1851.....490 - -He has had large experience of the patent laws (p. 490)--Has never taken -out one, and is of opinion that the system is productive of immense evil -(p. 491)--Reasons for this belief (p. 491)--Conditions necessary for a -successful patent (p. 493)--Disadvantages of patents (p. -494)--Impediments in the way of improvements (p. 495). - -82. Extract from Observations on the Patent Laws made by Mr. Brunel at a -Meeting of the Society of Arts (March 28, 1856).....497 - -83. Letter from Philae, describing the Ascent of the Cataracts (February -12, 1859).....517 - -84. Report to the Directors of the Great Western Railway Company on the -Broad Gauge, &c. (August 1838).....525 - -He is desirous of combining his views into one report (p. 525)--The -difficulties have been overcome, or are gradually diminishing (p. -525)--And the result justifies the attempt which has been made (p. -526)--The gradients of the Great Western Railway are favourable (p. -526)--Advantages of the broad gauge (p. 527)--Reasons for adopting it -(p. 528)--Additional cost in construction is very slight (p. -529)--Weight of carriages (p. 530)--Freedom from accidents (p. -531)--Greater space for works of locomotives (p. 532)--The greater width -gives scope for improvement in every part (p. 532)--Speed obtained (p. -532)--Design of the engines (p. 533)--The continuous system of permanent -way is best adapted to high speeds (p. 535)--Calculations as to its cost -compared with that of a well constructed line with stone blocks (p. -537). - -85. Report to the Directors of the Great Western Steam-Ship Company, -recommending the Adoption of the Screw Propeller in the 'Great Britain' -Steam-ship (October 1840),.....539 - -This subject will be considered under two heads: 1. The efficiency of -the screw propeller, compared with the paddlewheel. 2. The advantages or -disadvantages attending its use (p. 539)--The first question involves -the consideration not merely of the effect produced, but also of the -proportionate power absorbed in producing that effect (p. -539)--Observations on the slip of the paddlewheel and screw in the -'Great Western' and 'Archimedes,' respectively (p. 540)--The result of -the comparison being, that with similar areas the screw will meet with -at least equal, if not a greater resistance, and will consequently slip -as little as or less than the ordinary paddle-board (p. 542)--Refutation -of the common error, that the action of the screw is a very oblique one, -and that it imparts a considerable rotatory motion to the water (p. -543)--Description of the action of the screw (p. 543)--The result of the -experiments is that, as compared with the ordinary paddlewheel of -sea-going steamers, the screw is, both as regards the effect produced -and the proportionate power required to obtain that effect, an efficient -propeller (p. 548)--Objections to the use of the screw propeller (p. -548)--Answered seriatim (p. 549)--Statement of the principal advantages -peculiar to the use of the screw (p. 552)--The result of these enquiries -is a strong and decided opinion in favour of the screw propeller being -adopted in the 'Great Britain' steam-ship (p. 557). - - - - - - -LIST - -OF - -ILLUSTRATIONS. - - -_ENGRAVINGS._ - -Portrait (engraved with permission of Messrs. Graves and Company by -T. O. Barlow, from a portrait by J. C. Horsley, R.A., in the possession -of Mrs. Brunel). ....._Frontispiece_ - - -PLATE. ....._to face_ PAGE - - I. The Clifton Suspension Bridge.....49 - - II. The Hungerford Suspension Bridge.....59 - -III. The Royal Albert Bridge at Saltash. General View......171 - - IV. The Newport, Windsor, and Chepstow Bridges. Elevations -and Sections.....206 - - V. The Royal Albert Bridge at Saltash. Elevations and Sections......218 - - -_WOODCUTS._ - -FIG. .....PAGE - -1. Maidenhead Bridge (longitudinal section).....174 - -2. Bourne Viaduct (outline elevation).....181 - -3. Ivybridge Viaduct (the same).....182 - -4. Landore Viaduct (the same).....184 - -FIG. PAGE - -5. St. Pinnock Viaduct (outline elevation, transverse section, and - plans of piers).....187 - -6. Experimental Girder (transverse section).....193 - -7. Girder on South Wales Railway (the same).....194 - -8. Girder on Eastern Bengal Railway (the same).....195 - -9. Cumberland Basin Swing Bridge (transverse section of girder).....196 - -10. Windsor Bridge (transverse section of truss).....200 - -11. Chepstow Bridge (the same).....208 - -12. Saltash Bridge (the same).....219 - -13. Transverse Section of the 'Great Britain' Steam-Ship.....256 - -14. Copy of a Sketch in a Letter on Iron Ships.....259 - -15. Transverse Section of the Cradles and the Launching Ways of - the 'Great Eastern' Steam-Ship.....347 - -16. Longitudinal Section, Plan, and Midship Section of the 'Great - Eastern' Steam-Ship.....397 - -17. Monkwearmouth Dock Gates.....421 - -18. Bristol Dock Gate.....430 - -19. Plymouth Great Western Dock Gates.....435 - -20. Briton Ferry Dock Gate.....439 - -21. Brentford Dock Gate.....441 - -22. Renkioi Hospital.....470 - - - - -LIFE - -OF - -ISAMBARD KINGDOM BRUNEL. - - - - -CHAPTER I. - -_EARLY LIFE._ - -A.D. 1806--1828. - - BIRTH OF MR. BRUNEL, APRIL 9, 1806--SIR MARC ISAMBARD BRUNEL--THE - BLOCK MACHINERY--MR. BRUNEL'S SCHOOL LIFE--THE THAMES - TUNNEL--SINKING OF THE ROTHERHITHE SHAFT--DESCRIPTION OF THE - SHIELD--EXTRACTS FROM SIR ISAMBARD BRUNEL'S JOURNALS FROM THE - COMMENCEMENT OF THE THAMES TUNNEL TO THE DATE OF THE SECOND - IRRUPTION OF THE RIVER, JANUARY 12, 1828--_NOTE A:_ THE BOURBON - SUSPENSION BRIDGES--_NOTE B:_ EXPERIMENTS WITH CARBONIC ACID GAS. - - -ISAMBARD KINGDOM BRUNEL was born on the ninth day of April, 1806, at -Portsmouth, and was the only son of Sir Marc Isambard Brunel.[1] - -Most biographies commence with an account of the parentage of the person -whose life is about to be written. If this be permitted in any case, no -apology can be needed for prefixing to a Life of Mr. Brunel some -particulars of his father's career, since he was indebted to him, not -only for the inheritance of many natural gifts, and for a professional -education such as few have been able to procure, but also for a bright -example of the cultivation of those habits of forethought and -perseverance, which alone can ensure the successful accomplishment of -great designs. - -Sir Marc Isambard Brunel was a native of Hacqueville, a village in -Normandy, where his family had been settled for several generations. He -was originally intended for the priesthood; but, as he showed no -inclination for that calling, and a very decided talent for mechanical -pursuits, he was permitted to enter the French Navy; and he served in -the West Indies for six years, namely, from 1786 to 1792. On his return -home, at the expiration of his term of service, his strong Royalist -sympathies made it unsafe for him to remain in France, and with great -difficulty he managed to escape to America. He landed at New York in -September 1793, and soon obtained employment as a civil engineer. A few -years afterwards he was appointed engineer to the State of New York; -and, while holding that office, he designed a cannon foundry and other -important public works. - -In January 1799, when Sir Isambard was in his thirtieth year, he came -over to England, and shortly after his arrival married Miss Sophia -Kingdom, a lady for whom he had formed an attachment some years -before.[2] - -The first great work undertaken by him in this country was the machinery -for making blocks, which he designed and erected for Government at -Portsmouth. - -The history of the invention and construction of this system of -machinery (for it consisted of _forty-three_ separate machines) need not -be given at length; but it may be permitted to extract the following -passage from Mr. Beamish's 'Life of Sir Isambard Brunel' (pp. 97, 99, -2nd edition), in which he points out the benefits which have resulted -from its introduction, and the position its inventor is entitled to hold -among those who have contributed to the progress of mechanical science. - - Where fifty men were necessary to complete the shells of blocks - previous to the erection of Brunel's machinery, four men only are - now required, and to prepare the sheaves, six men can now do the - work which formerly demanded the labours of sixty. So that ten men, - by the aid of this machinery, can accomplish with uniformity, - celerity, and ease, what formerly required the uncertain labour of - one hundred and ten. - - When we call to mind that at the time these works were executed, - mechanical engineering was only in its infancy, we are filled with - amazement at the sagacity and skill that should have so far - anticipated the progress of the age, as to leave scarcely any room, - during half a century, for the introduction of any improvement.... - - Beautiful as are the combinations and contrivances in the block - machinery, and highly deserving as the inventor may be of credit - for originating such labour-saving machines for the production of - ships' blocks, there is a far higher claim to the admiration and - gratitude of all constructors of machinery, and of all workers in - metal. In this block machinery exist the types and examples of all - the modern self-acting tools, without the aid of which the various - mechanical appliances of the present day could not be produced with - the marvellous accuracy which has been attained. It is true that to - the trades unions or combinations among the artisans, is in a great - measure directly due the introduction of self-acting machines; but - the types of all these tools existed in the machines and - combinations of Brunel's block machinery. The drilling, the - slotting, and the shaping machines, the eccentric chuck, and the - slide rest, with the worm wheel motion, are all to be found in his - machine. - -On the completion of the block machinery Sir Isambard Brunel removed to -London, and took a house in Lindsay Row, Chelsea, where he remained -until he was obliged to live nearer the works of the Thames Tunnel. - -Mr. Brunel's first recollections were of the house at Chelsea; and in -1814, when he was eight years old, he commenced his school life under -the Rev. Weeden Butler, who resided in the neighbourhood. Previously to -his going to Mr. Butler, he had been taught Euclid by Sir Isambard; and -he had also a great talent for drawing, for which he had been remarkable -even from four years old. His drawings were beautifully precise and -neat, but, when the subject admitted of it, full of vigour and -picturesque effect. - -After some time he was sent to Dr. Morell's school at Hove, near -Brighton. The following extract is taken from one of his letters home in -1820:-- - - I have past Sallust some time, but I am sorry to say I did not read - all, as Dr. Morell wished me to get into another class. I am at - present reading Terence and Horace. I like Horace very much, but - not as much as Virgil. As to what I am about, I have been making - half a dozen boats lately, till I have worn my hands to pieces. I - have also taken a plan of Hove, which is a very amusing job. I - should be much obliged to you if you would ask papa (I hope he is - quite well and hearty), whether he would lend me his long measure. - It is a long eighty-foot tape; he will know what I mean. I will - take care of it, for I want to take a more exact plan, though this - is pretty exact, I think. I have also been drawing a little. I - intend to take a view of _all_ (about five) the principal houses in - that great town, Hove. I have already taken one or two. - -In the intervals of his classical studies he seems to have employed -himself, not only in making a survey of Hove in its existing state, but -also in a critical examination of the works in progress for its -enlargement. It is told of him that one evening he predicted the fall, -before the next morning, of some houses which were building opposite the -school, and laid a bet on the subject, which his companions readily -accepted. He had noticed the bad way in which the work was done, and -that the stormy weather, which appeared to be setting in for the night, -would probably blow the walls down. In the morning he claimed the -wager, for the buildings had fallen in the night. - -Except from November 1820 to August 1822, when he was at the College -Henri Quatre at Paris,[3] Mr. Brunel was so very little absent from home -that he became thoroughly acquainted with all his father's undertakings. -Among these was the veneering machinery at Battersea, remarkable for the -great diameter of the saw, the steadiness of its motion, and the -mechanical arrangements for clearing the veneer from the saw; also the -works at the Government establishments at Woolwich and Chatham, and the -machinery for making shoes. They have been fully described by Mr. -Beamish; but the mere mention of their names is enough to show how great -were the advantages enjoyed by Mr. Brunel in receiving from his father -his early professional education. - -From the year 1823 Mr. Brunel was regularly employed in his father's -office. It was in the early part of this year that the project of the -Thames Tunnel first began to occupy Sir Isambard's attention; but he was -also engaged at that time in other works of great importance, among them -the suspension bridges for the Ile de Bourbon, and designs for bridges -of the same character over the Serpentine, and over the Thames at -Kingston.[4] Some account of the Bourbon bridges, and also of -experiments with carbonic acid gas, on which Mr. Brunel was engaged, -will be found in the notes to this chapter. - -The history of the Thames Tunnel will be told, as far as possible, in -Sir Isambard Brunel's own words, as given in his journals.[5] Although -these extracts do not relate to works for which Mr. Brunel was -personally responsible, they have been inserted in the belief that they -are valuable, not only as showing the nature and extent of his duties as -his father's assistant, but also as displaying, in the most interesting -and authentic form, Sir Isambard's character and genius at a time when -his son was brought into hourly contact with him, and under -circumstances which would cause the influence of his example to make a -deep and lasting impression. - -Previously to the year 1823 there had been several plans suggested for -the construction of a tunnel under the Thames; and it would seem that a -great demand was supposed to exist for some such means of communication -between the two sides of the river eastward of London Bridge; for after -the failure of the operations undertaken by Mr. Vasie in 1805, and Mr. -Trevethick in 1807,[6] a high level suspension bridge was proposed, -although it was not intended to be used for heavy traffic.[7] - -The first reference to the Tunnel in Sir Isambard's journals is dated -February 12, 1823. 'Engaged on drawings connected with Tunnel;' and on -the 17th and following days of the same month, 'Isambard was engaged on -Tunnel.' These entries become more and more frequent in the pages of his -diary, until it is evident that Sir Isambard's whole time and thoughts -were absorbed in this work. - -The spring of 1823 was occupied in preparing drawings and models of his -plans, and in enlisting the sympathy and assistance of various -influential persons. By the close of the year the designs were matured -sufficiently to enable the promoters of the scheme to commence the task -of organising a company for carrying it out; and in January 1824 they -resolved to call a general meeting of their friends, and invite public -subscriptions. - -On February 17, Sir Isambard explained his plans at the Institution of -Civil Engineers, and on the next day a meeting was held at the City of -London Tavern, under the presidency of Mr. William Smith, M.P., more -than a hundred persons being present. Resolutions authorising the -formation of a company were passed unanimously, and the share list was -opened. In the course of an hour one-third of the subscriptions was -filled up, namely, 1250 shares; and before the end of the day the number -of shares taken was 1381. - -Borings were then commenced in order to ascertain the nature of the -strata through which the Tunnel would pass. A bed of gravel was found -over the clay, which gave Sir Isambard great anxiety. A large pipe or -shaft was sunk on the side of the river, and in it the water rose to -within three feet of the surface of the ground, and fell about eighteen -inches with the tide. 'It is manifest (Sir Isambard writes) from this -that unless the Tunnel is enclosed in the stratum of clay, it would be -unsafe to drive through the bed of gravel. The Tunnel must, therefore, -begin with the substantial clay.' - -However, the result of thirty-nine borings in two parallel lines across -the river, to the depth of from 23 to 37-1/2 feet, seemed to prove that -there was below the gravel a stratum of strong blue clay of sufficient -depth to ensure the safety of the Tunnel.[8] - -A report to this effect was made to the shareholders at their first -general meeting in July, and it was also stated that the works would be -completed in three years. - -The first operation connected with the works, was the constriction of a -shaft; and for this purpose land was bought on the Rotherhithe bank, -about fifty yards from the river. On March 2, 1825, the ceremony of -laying the first stone of the shaft was performed. - - Mr. Smith, our chairman, attended by most of the members of the - Court of Directors, and a very numerous cortege of friends invited - on the occasion, proceeded from the Tunnel Wharf to the ground, - where they were received among the cheers of a great concourse of - people. Mr. Smith addressed the assembly in a very eloquent speech - suitable to the occasion, and performed the ceremony of laying the - first stone. From this day dates the beginning of the work.[9] - -The mode in which Sir Isambard decided to construct the shaft was one -not uncommonly adopted in the construction of wells; but to apply it to -sinking a shaft fifty feet in diameter was a novel and bold undertaking. -The brickwork intended to form the lining of the shaft was built on the -surface of the ground, and the earth being excavated from within and -underneath the structure, it sank gradually down to its final position. - -The brickwork was 3 feet thick, bound together by iron and timber ties, -and there were built into it 48 perpendicular iron rods, one inch in -diameter, fastened to a wooden curb at the bottom, and to another curb -at the top of the wall, by nuts and screws. - -When the shaft or tower of brickwork was completed up to the top, 42 -feet in height, the next step was to remove the blockings on which it -rested, and this being done the gravel was excavated and hoisted up, and -the shaft descended by its own weight. - -The Rotherhithe shaft was only sunk forty feet in this manner; the -remaining twenty feet, in order to leave the opening for the Tunnel, was -constructed by under-pinning, or underlaying, as it was then termed. The -underlaying was commenced in the beginning of June.[10] - -By July 4 they had got down to the level of the intended foundation of -the shaft, having passed into a stratum of gravel, black pebbles -embedded in greenish sand, with little or no water; from which -circumstance Sir Isambard was of opinion that it was unconnected with -the stratum of gravel above. - - _July 12._--Engaged on a general drawing for the great shield, and - in preparing some instructions for moving the same (a very - intricate operation!) - - _July 22._--Underlaying is a very laborious mode of proceeding. The - sinking of a wall well bound as the first, would evidently be the - best and cheapest mode for making another tower of 50 feet - diameter. - -On the 28th Sir Isambard enters in his journal the following additional -observations upon the success of his plans for sinking the shaft:-- - - Considering the great labour necessary for securing the ground for - the underlaying, the waste of planking, and of shores, and the time - necessarily taken up in moving about, in securing and in baling - out the water, and the many causes of interruption, and the - imperfect way that things are done in underlaying, it is quite - conclusive that the original plan of making a shaft, by sinking the - structure, is the safest and the most economical. What is done is - sound, and when once in place, may be secured with foundations in a - very easy manner. The brickwork of the shaft is remarkably hard. - Had it been made with brick facings and rubble stone, it would - certainly be water-tight, and almost impenetrable by ordinary ways. - The _vertical ties_ and the _circular wall bands_ are not to be - dispensed with in a structure destined to be moved as the present - has been. - -On August 11 the underlaying was completed, and preparations were made -for constructing a reservoir in the bottom of the shaft for receiving -the permanent pumps. This was finished on October 11, with great -difficulty, owing to the nature of the ground, which consisted of loose -sand containing a large quantity of water. - - _August 19._--Engaged at home in revising my plans for the manner - of carrying on the horizontal excavation, more particularly of - penetrating through the shaft. This part of the operation requires - _indeed_ very great attention, as it presents great difficulties, - arising from the wall to be broken through, and chiefly from the - angular opening that is to be made at each extremity. Then another - consideration is the uniting the brick arches to the brickwork of - the shaft. - - _September 16._--Engaged in the early part of the day on revising - my plans of future operations in the Tunnel work, and in adapting - them to the nature of the ground as it is found at the various - depths we have penetrated: namely, to about 73 feet. Went - afterwards to Maudslay to request that the great shield may be - completed. - - [Sidenote: Great shield.] - - _October 14._--Engaged in the early part of the morning in making - some arrangements for the working of the great shield. Too much - attention cannot be given to that subject at the early part; for, - when once in its place, it would be extremely inconvenient to make - any alteration. - - [Sidenote: Preparing for the frames.] - - _October 15._--The dome of the reservoir will be covered to-day - about noon; the bottom of the shaft will therefore be completed. - They are now preparing to apply two frames of the shield. The - ground now open in the front is remarkably hard; it consists of - pebbles imbedded in a chalky substance, with hard loose stones of - the nature of the Kentish rag. Everything is going on well. Devised - with Isambard how to make our wells for the descent of the - materials, &c. - -Thus at last the shaft was completed, and Sir Isambard was able to -commence the Tunnel itself, which he ultimately determined to construct -in the form of a rectangular mass of brickwork, 37-1/2 feet wide and 22 -feet high, pierced by two parallel horseshoe archways, each 14 feet wide -and 17 feet high. - -Before entering upon the history of this undertaking, some account must -be given of the machine which Sir Isambard Brunel devised for effecting -its accomplishment. - -In order to avoid a quicksand of considerable depth and extent, the -Tunnel had to be carried but a short distance below the bed of the -river; and, as in all tunnelling through soft soil,[11] the top and -sides of the excavation had to be supported until the brickwork was -built in; and the front or face had also to be held up as the miners -advanced. This support was given by means of a machine called 'the -shield,' described on one occasion by Sir Isambard as 'an ambulating -cofferdam, travelling horizontally.'[12] - -The main body of the shield consisted of twelve independent structures -or 'frames' made of cast and wrought iron. They were each 22 feet high, -and rather more than 3 feet wide; and, when placed side by side, like -books on a shelf, against the face of the excavation, they occupied the -whole area of the face, and also the top, bottom, and sides for 9 feet -in advance of the brickwork. Each frame stood on two feet resting on -the ground, and was divided in its height into three cells by cast-iron -floors. In these cells, of which there were thus thirty-six in all, the -miners stood, and worked at the ground in front of them. - -The duty which the shield had to perform was to support the ground until -the brickwork was built within the excavation; but it was essential that -this should be done in such a manner as to allow of the mining -operations being carried on; and it was also necessary that the machine -itself should be capable of being moved forward. - -The first point, therefore, which has to be explained in the action of -the shield is the manner in which the earth was supported by it. - -It has been already stated that each frame rested upon two feet, or -large iron plates. These two feet together covered the ground under the -frame to which they belonged, and thus the whole of the earth beneath -the frames was pressed down by the feet. - -The earth above was supported by narrow iron plates, called staves, laid -on the heads of the frames parallel to the line of the Tunnel, the ends -resting on the completed brickwork behind it. The earth at the sides was -kept up by staves resting against the outermost frames. - -The arrangement for holding up the earth at the face of the excavation -was necessarily of a more complicated character. Each frame supported a -series of boards called poling-boards, by means of small screw-jacks or -poling-screws, two to each poling-board, which abutted against the -frames, and pressed the boards against the earth. The boards were 3 feet -long, 6 inches wide, and 3 inches thick, and were arranged horizontally. -These poling-boards, more than five hundred in number, covered the whole -surface in front of the frames. - -To resist the backward thrust of the poling-screws against the frames, -each frame was held forward by two large screws, one at the top of the -frame, and the other at the bottom, abutting against the brickwork of -the Tunnel. The brickwork was completed close up behind the shield as it -advanced. - -The way in which the earth was excavated, and the shield moved forward, -has now to be explained. - -The plates or staves which supported the ground at the top and sides of -the shield were pushed forward separately by screw-jacks; but in order -to advance the poling-boards in front, it was necessary that that -portion of the ground against which they pressed should be removed. - -The miner, standing in his cell, took down one, or, at the most, two of -the poling-boards, commencing at the top of the cell, and having -excavated the earth a few inches in advance, replaced the poling-boards -against the newly-formed face, pressing them against it with the -poling-screws. Thus the excavation was carried on without depriving the -ground of the support it received from the shield, except at the point -where the miner was actually at work. - -The operation of advancing the frames was effected in the following way. -When everything was ready for a move, one of the feet which carried the -frames on jointed legs was lifted up, and advanced forward a few inches, -and then pressed down on to the ground, until in its new position it -again bore the weight of the frame. This done, the other foot was -lifted, moved forward, and screwed down in the same manner, and then the -frame itself was pushed ahead by means of the large abutting screws, -which kept it top and bottom from being forced back on the brickwork. - -It is, however, evident that these abutting screws would have been -unable to push on the frame, while the ground in front was pressing back -the poling-boards against it; therefore, during the process of moving a -frame, it had to be relieved from the thrust of its poling-screws. -Accordingly, when it was desired to advance any one of the frames, the -butts of the poling-screws of the tier of boards in front of it were -shifted sideways, so as to rest, not against the frame to which they -belonged, but against the frames next it on either side. This done, the -frame itself was advanced, and was then ready to receive again its own -poling-screws, and also those belonging to the adjoining frames, so that -they might in their turn be moved forward. It will thus be seen that the -whole shield was not moved forward at one time, but that the frames were -advanced alternately. - -There were many other ingenious arrangements in the design of the -shield, which need not be referred to in a description intended only to -give such a general idea of the machine as may make the history of its -operation intelligible.[13] - -When the frames had been completed in Messrs. Maudslay's factory, they -were conveyed to Rotherhithe, and lowered down the shaft. An opening had -been left at the bottom of the wall, about 37 feet wide by 22 feet high, -and against this the shield was erected. It was then ready to commence -its progress through the ground below the river. - -On November 25, 1825, the shield made its first start. Sir Isambard was -unfortunately unable to witness what was in fact the actual commencement -of the Tunnel, as he had three days before been seized with a sudden and -alarming attack of illness, which kept him at home till December 6. The -works were left under the direction of Mr. Brunel. - - _December 8._--The great shield is advancing very slowly, meeting - with much interruption by the water, which still runs within the - cells, and also by the difficulty of forming abutments for the - frames. [_Temporary abutments were necessary until the shield was - sufficiently advanced to allow of its being pushed forwards from - the brickwork built up behind it._] - - _December 29._--The frames are very much out of level in the - transverse line of the Tunnel. This would be attended with serious - inconvenience if I had not provided for the means of recovering any - irregularity that might take place, and which, as it appears, - cannot perhaps be prevented; but having foreseen this, I have - provided the remedy by being able to take down the top of each - frame, and to remove the top staves in parts, or the whole, at - pleasure--a very important provision it proves to be. - - _January 16, 1826._--Too much precaution cannot be taken, in the - management of the frames, to have the leg-screw particularly well - secured, as every foot-run of the arch of the Tunnel sustains 82 - tons. Each frame carries as follows:-- - - The two end frames each 65 tons = 130 - Ten others, each 52-1/2 " = 525 - --- - 655 tons. - - _January 21._--The ground at the top and sides very good; same in - the front. In breaking the ground out of the limits of the shield - on the right a great deal of ground fell in. This indicates that, - if it was not for the protection of the shield, nothing could be - done. This accounts also for the occasional breaking of the ground - in making the drift in 1809. - - [Sidenote: Tunnel begun.] - - The brickwork of the entrance being carried as far as directed, the - body of the Tunnel was begun to-day. - - [Sidenote: Water broke into the works.] - - _January 26._--Isambard went down to Rotherhithe; the water had - broken in in great abundance upon the work over Nos. 4 and 5. [_The - twelve frames were distinguished by numbers._] A 4-inch pipe was - driven over the shield from inside the shaft, but the water did not - follow it, and the stream augmented very rapidly. The frame No. 5 - was moved forward, and it checked the water for a moment, but it - came again with violence. A heading was immediately ordered by - Armstrong [_the resident engineer_] from the east well, in which - Isambard concurred. - -_February 3_.--Ordered a pit to be opened and made by sinking a curb 8 -feet diameter and 18 inches thick, well bound with bolts. [_This pit was -a well sunk from the surface to enable the gravel containing water, into -which the head of the shield had penetrated, to be removed, and clay -substituted_.] - -_February 6_.--The shaft begun last night, and was sunk 20 feet to-day, -and remarkably true. Had we known the ground as we now know it, we -might, by having opened a well contiguous to the great shaft, have sunk -the shaft in a week; but for that purpose we must have had two steam -engines, one for pumping the water, and the other for taking up the -ground. - -[Sidenote: Unremitted attention wanted.] - -_February 10_.--Went very early to the Tunnel for the purpose of giving -directions to prop up the back of the staves, which, for want of weight -at the new shaft, might be overbalanced by the pressure of the ground at -the back. I could not rest a moment until it was done, for the -consequences might have been fatal, at this moment in particular. What -incessant attention and anxiety! To be at the mercy of ignorance and -carelessness! No work like this. - -[Sidenote: Observations on the mode adopted to check the water.] - -_February 12_.--The ground having been opened carefully from under the -curb of the pit [_see above on date February 3_], the greater part of -the gravel was removed, and stiff clay substituted for it. This was done -by driving first some wrought-iron flat bars, which kept the ground up. -This shows that the shield is a most powerful protection, and would -enable us to penetrate through a bed of gravel. Though the breaking in -of the water had somewhat terrified the man in No. 5, he soon returned -to his post, and the others have acknowledged their full confidence in -the security afforded by the shield. The boring ahead had not yet been -attended to: it is owing to the want of this precaution that this -accident is chiefly to be ascribed; for had we known as much as we now -do, we might have passed through without the pit being opened. - -_March 1_.--Water at the back of the frames, but less than before. The -men show a great deal of spirit in overcoming the present difficulties. -Isambard was very busy yesterday and to-day in the frames, and about the -works. He was severely hurt in the leg by a piece of timber falling -against it. [_This accident prevented his attending again at the Tunnel -until the 24th_.] - -On March 6 the proprietors paid a visit to the Tunnel, and were highly -satisfied with what they saw. On that evening Sir Isambard writes:-- - - It is of absolute necessity _now_ to provide for everything that is - conducive to the more expeditious management of the frames, and to - a greater facility in getting up the brickwork. If these two points - are realized, then indeed we may soon expect to be moving at a good - rate--not less than I have held out, namely, 3 feet per 24 hours. - - [Sidenote: Water stopped as expected.] - - _March 11._--Received early in the morning a report from Armstrong - stating that the water was completely stopped--that it had been - stopped during the night. Aware that we had passed the gravel, it - was of course expected that we were under the clay; means were - therefore resorted to, to drive clay and oakum at the tail of the - top staves, which was productive of a very good effect. The great - shield was soon entirely free of water. This shows the efficiency - of the shield to oppose difficulties which could not have been - overcome without the complete protection it affords, under almost - any circumstances. Indeed this has been a tedious operation since - January 25, when the water first burst upon No. 5, at the front of - the shield. The miners as well as the bricklayers have worked with - great spirit and perseverance through the whole, during a period of - 44 days. The well that was made at the front of the shaft has been - of use in acquainting us with the extent of the open ground we had - to pass through. It will be made a useful opening for ventilating - the works. By means of this well we have been able to apply the - lead pipes with which the water has been diverted: it is not - therefore a useless expense. Things were put in better order to - prepare for a more expeditious way of working. Directions were - given to place the frames in a better condition. Isambard is still - too unwell to go to the Tunnel. - - [Sidenote: Considerable slip of ground: how to check it.] - - [Sidenote: Very dangerous.] - - _March 25._--Went to the Tunnel with Isambard. Found that a - considerable fall of ground had taken place again at the right - side. No one could account satisfactorily for it. I inspected it, - and directed that, after making it good, flat bars of iron be - driven at the head of the side staves, in order to pin it up, and - in order to enable the miners to get at the solid ground. It is - very bad and extremely dangerous; the ground is evidently the same - as that which, in the report of the first attempt, was found so - loose as to have dropped upon the works, leaving a large cavity - above, when it is said the man ascended and made good the hole. We - should be warned by this, lest we should meet another as fatal as - it ultimately was on that occasion. [_This observation refers to - the driftway of 1807._] - - _April 24._--By Armstrong's report the water is entirely out, and - the men at work in the morning in removing the dirt, &c. Isambard - engaged at the Tunnel, where I am not yet able to attend as often - as I could wish. Everything goes on well, much through his - exertions. - - _May 11._--One hundred feet will be completed to-night. - - _May 22._--The top plate over the frame No. 1 has been cracked - without any particular violence or stress. It appears that it is - nothing but the change of temperature that is the cause of that - rupture. The accident justifies the opinion I have of cast-iron not - being safe upon traction, and the precaution of having had - wrought-iron bolts at the back of the frames. [_These were vertical - rods which took the tensional strain._] Without these bolts what - would have become of the shield, if one casting was to break? The - fracture was accompanied with a loud report like that of a gun. - Isambard was in the works at the time of breaking: nothing could - have prevented it. - - [Sidenote: The shield being too much out, resolved to move it - bodily.] - - _May 25._--I observed that nothing whatever had been gained to - recover the deviation [_the shield had gradually worked 2 feet 3 - inches to the westward_], which subjects us to so much - inconvenience and loss of time. The only way to bring the shield - right is by taking the frames sideways. - - _June 3._--Finding it too laborious and almost fruitless to bring - the frames in the right way, I came to the determination of having - them brought bodily to the east by cutting the ground on the side. - I accordingly gave directions to Armstrong to proceed in making a - heading out of No. 12, and by securing the side staves to continue - downwards until the ground be clear. The working was accordingly - discontinued in front. - - _June 4._--The mode of proceeding by the common way of mining shows - the impracticability of carrying a large excavation anywhere, - particularly under a considerable body of water. The expense of - timbering would be too great, even if it could be sound. The ground - above the frames is remarkably good, but under it there is a - stratum of silt which breaks and falls in large masses. - - [Sidenote: Isambard's service very important and most efficient.] - - _June 5._--Isambard got into the drift, and gave the line for the - better disposition of the staves, which was afterwards done in a - proper manner. Isambard's vigilance and constant attendance were of - great benefit. He is in every respect a most useful coadjutor in - this undertaking. - - _June 10._--The last frame (No. 1) is brought close to the others, - and the brickwork brought up to fill the back. - - [Sidenote: Dangerous state of the ground. Precautions taken.] - - _June 15._--On inspecting the face of the ground this morning I - observed a breach in the front of Nos. 3, 4, and 5, where the - ground has given way in the lower cell. This was truly alarming. I - ordered iron staves to each floor in order to pin the ground, and - thereby to counteract the slipping which would immediately take - place. - - _June 19._--The bricklayers left off work, but, on enquiring into - the cause, I learned there was no other but to have a libation upon - the new arrangement of piece-work. - - _June 29._--Gave positive directions to cut only 4-1/2 to 5 inches - thick at a time at the front of the top cells, instead of 9 inches, - as they had done for some time. - - _July 3._--The great question is, does the clay undulate at its - surface? We should have some reason to apprehend that it does so, - because at the beginning we had not proceeded many feet into the - clay when we struck again into the gravelly stratum. The surface of - the clay must therefore have sunk at that particular spot; which - circumstance seems to warn one of the need of great vigilance and - great prudence in the progress of the enterprise. - - [Sidenote: Cofferdam burst at Woolwich.] - - [Sidenote: Warning for us.] - - _July 10._--A cofferdam burst yesterday at the works at Woolwich, - having blown up from the foundation. How cautious this should make - our men! The cofferdam may be repaired, and very easily too, but an - irruption into the Tunnel--what a difference, particularly at this - early period! - - [Sidenote: Carelessness of the miners.] - - _August 10._--Found the lowest cell of No. 1 left by the workmen - _without a single poling against the ground_. This is indeed a most - unjustifiable neglect. - - _August 12._--At six this morning completed 205 feet. - - [Sidenote: Observations on the bad effect and consequence of - driving on as is done.] - - _August 21._--This piece-work has not been productive of much - effect as to quantity of work. As to quality it is very - questionable. A work of this nature should not be hurried in this - manner. Fewer hands, enough to produce 9 feet per week, would be - far better than the mode now pursued _from necessity_, but not from - inclination on my part. Great risks are in our way, and we increase - them by the manner the excavation is carried on. The frames are in - a very bad condition. - - _September 5._--It is much to be regretted that such a work as the - Tunnel should be carried on by the piece. Obliged to drive on, no - time is left to make any repair, or to recover any lost advantage. - Isambard is most active. Mr. Beamish shows much judgment in his - exertions, and zeal in his attendance.[14] - - [Sidenote: Water breaking in at back of frames.] - - [Sidenote: How to check it. Isambard's exertions.] - - _September 8._--About 2 P.M. I was informed by Munday that water - was running down over No. 9. I went immediately to it. The ground - being open, and consequently unsupported, it soon became soft, and - settled on the back of the staves, moving down in a stream of - diluted silt, which is the most dangerous substance we have to - contend with. Some oakum was forced through the joints of the - staves, and the water was partly checked. Isambard was the whole - night, till three, in the frames. At three I relieved him. He went - to rest for about a couple of hours; I took some rest on the stage. - - [Sidenote: Things improving.] - - _September 9._--Towards noon the stream changed its character. The - clay, being loosened by the water, began to run, but it thickened - gradually. It was late in the evening before the loosened clay - acquired the consistency of a loose puddling, which covered the - staves, and made them a complete shield against further irruption, - or rather, oozings of mud. If we consider that at this place we - have at the utmost 9 feet between the top staves and the gravel, - over which the river flows, it is most satisfactory and most - encouraging to have this additional proof of the protection which - the shield affords. At nine o'clock at night Isambard sent me word - that 'tout va a merveille;' indeed it was so, for it was like a - stopper interposed between the river and the top-staves. Instructed - as the men were by the first accident, they went on as usual in the - irrespective occupations. Pascoe, junr., and Collins were - remarkably active and persevering, and some other men equally so; - while old Greenwell encouraged them by a speech of his own in high - commendation of the security of their situation. - - [Sidenote: Water more abundant. Is it from the river?] - - _September 12._--The water, bringing with it a sort of clay broken - in small particles, increased to an alarming degree. In consequence - of this continued displacement of the silt and clay, a cavity had - been formed above the staves. At about three, when I had gone to - the Court of Directors, the ground fell upon the staves with great - violence, causing a surge most alarming as to probable - consequences. Isambard was at that moment in the upper frames, and - he gave directions for increasing the means of security. On my - return I found things much worse than I left them, but every means - of security was judiciously applied. During the night in - particular things presented a very unfavourable appearance. The - men, however, were as calm as if there were no other danger to be - dreaded than wet clothes or the splashing of mud. I observed the - men in the lower cells were _sound asleep_. - - [Sidenote: Exertions by the men.] - - [Sidenote: Slight improvement.] - - _September 13._--Every means were resorted to in the course of the - night and during the early part of the day to stop the water. The - men have shown great zeal and good management in their respective - avocations, and above all the utmost confidence. Isambard has not - quitted the frames but to lay down now and then on the stage. I - have prevailed on him to go to his bed, or rather, used my - endeavours to induce him; but he has not since last Friday night - (the 8th). Things were rather better at the close of the day. - - _September 14._--Things upon the whole have assumed a more - favourable aspect. The situation is nevertheless very critical. - Nothing but the utmost precaution in following up what has begun - can bring us out of it. This has been a most eventful week! - - _September 18._--Isambard was the greater part of the night in the - works, and the benefit of his exertions is indeed most highly felt: - no one has stood out like him! Everything is quite safe, the water - is kept back, and the work proceeds in a most satisfactory manner. - - _October 22._--It is evident [_from a flow of silt which had taken - place on that day_] that with the shield we have passed close under - a body of collected water a few inches only above the staves. - Isambard is too unwell to stay long in the works. - - [Sidenote: The want of a drain subjects us to much inconvenience.] - - _October 24._--The want of the main drain which was originally - intended to carry the water to the main reservoir is felt - everywhere. This drain is in my original plan, but the committee - expressing on several occasions a wish that I should dispense with - it, I complied, most reluctantly however, to prove my earnest wish - to reduce the expenses. It will not, I apprehend, be found an - economy. - - [Sidenote: Effect of the shoes in keeping the ground dense.] - - _October 26._--Every step we take shows how much security is - derived from the shoes, supporting as they do the shield and the - superincumbent weight. They press down in the same proportion the - ground on which they bear. They keep it as dense as it originally - was, and fit it for the structure that is to come upon it. It is - evident, therefore, that what is wanted is that the ground should - be kept pressed. It is with this object in view that I have - holdfasts and jacks. What incessant vigilance is required, what an - incessant call on the resources of the mind, not only to direct, - but more particularly to provide for many things that may occur. - - _November 17._--At this date 307 feet 9 inches had been - completed.[15] - - _December 8._--The evil [_that of not having a proper drain_] is - going on with us, and without any remedy except the drain, or a - cesspool by way of expedient. How much anxiety must one feel at - being so circumstanced! Should any water break in, how should we - proceed? This is another source of great solicitude. We have no - command of the frames when they rest upon wooden legs, or when the - screws are bent; and what is worse is that the men drive on without - any consideration or any fear of consequences. This circumstance, - and the apprehension of the water breaking in, are matters of the - most dreadful anxiety. - - [Sidenote: Superincumbent weight varying daily, and still more - every fortnight. What stress on the frames. The shoes have never - yielded; a most important circumstance.] - - _December 12._--Little do others know of the anxiety and fatigue I - have to undergo day and night. Advanced as we are, we have only - gained somewhat more experience, but the casualties are just the - same. An accident now might be as fatal as it would have been 200 - feet back, or as it would be 200 feet forwards. We have not a - period when we can think ourselves safe except when we have - connected these arches with a shaft on the other side. Loaded as we - are with the weight of the river, we have to advance our shield and - build our structure under that weight, a weight which varies twice - a day, and twice a month to a much greater extent. _The shoes are - the great foundation of our security._ When once pressed down with - the greatest power that can be applied, they do not give in the - least afterwards. They have not yielded even upon loose gravel; we - must therefore congratulate ourselves that they have answered so - completely. We have now walked our frames upwards of 350 feet; we - have had to renew the legs and the heads, but it is not through - want of strength so much as from mismanagement. The first legs were - never injured so long as their action was limited to 3 inches, but - when it was increased to 6 inches, they immediately gave way one - after another, without however any damage to the structure or to - the shield. The heads gave way, or began to give way, from the - moment the legs did; because, when a leg gave way, it brought upon - the contiguous frame an increased weight which broke the heads one - after another. That the breaking of so important a part of our - shield should not have been attended with any bad consequences is a - proof that provision had been made for the casualty. The proof that - it had been foreseen and provided for is in the manner these heads - were adapted to the frames. By the way they were fixed they would - be easily taken down and replaced. Though the heads gave way, the - top staves were not materially affected by it, and the service - continued until new heads were substituted. Some have fancied that - the ground did not bear wholly upon the shield and the arches, but - supported itself in parts. Experience proves that the pressure is - rather more than that which rests artificially on the frames. The - ground is compressed all round by the increased weight of high - water: we might therefore conclude that the shield operates as a - pillar, that supports beyond the limits of its base or cap. It is a - great satisfaction to be able to say that so long as we followed - the original plan, nothing gave way except the back screws. These - again were damaged by being run out of the sockets. We may - therefore ascribe most of the evils and damages to the increased - range of action, and still more to the rude implements the men have - used, whenever they met with any difficulty in moving the frames. - If it is considered that we had no other men to train in the use of - this immense machine but excavators and miners, very great - allowance must be made for what has occurred. - - [Sidenote: Falling of three facings from neglect. Awful!] - - _December 20._--An accident of an alarming nature occurred. The - poling-screws of Nos. 10 and 12, being on No. 11, Moul, the miner - in that frame, removed his butting screw; the consequence was that - the frame started back, the polings and poling-screws fell down - with a tremendous crash, and the ground followed to a considerable - extent. This is the most formidable accident that has yet occurred - in the face of the work. The ground was fortunately unusually firm, - and no fatal consequences ensued. - - _December 31._--Isambard and nine friends sat down to a dinner - _under the Thames!_ Now a year is over since we began to make any - progress horizontally, for we had only 11 feet of arch when the - water broke in on January 24 last. We may therefore say that the - whole of what has been made of the Tunnel has been made in that - period. It is worthy of remark that until the end of April no - fracture whatever, no bending of the legs, had taken place, - notwithstanding that we had supported for a period of nearly three - months a greater weight than we ever had since. The ground nearly - 40 feet high _kept sinking upon us_ as we advanced, and yet no - stave, no top, no leg gave way. Each leg was capable of carrying - nearly 80 tons at the point of fracture, consequently the aggregate - strength of 36 legs was equal to 2,880 tons, which is six times - over the greatest effort that could be exerted by the - superincumbent weight. The heads, after they had given way, - remained in place, some--namely, Nos. 1, 8, 12--for seven months, - and the others from four to six months. It cannot be said therefore - that there was a want of strength, since the broken heads continued - to perform for so many months after being so much damaged; nor is - there any defect in the iron. If the frames were, as some have - fancied, lanky, which implies weakness in their sides, how could - they have supported the alternate stress to which they are put by - standing alternately on one leg? Not one single joint has yet - started. Every frame has been upwards of 2,000 times in that raking - posture, consequently the shield has been upwards of 24,000 times - strained under the weight that has broken the heads. One single - side has broken, and is now as good as the rest. Is such a machine - to be stigmatised as it has been, without looking more minutely - into its operations? - - [Sidenote: Observations on the responsibility attached to this - enterprise.] - - _January 4, 1827._[16]--A work that requires such close attention, - so much ingenuity, and carried on day and night by the rudest hands - possible--what anxiety, what fatigue, both of mind and body! Every - morning I say, Another day of danger over! - - _January 12._--It is astonishing how the silt resists the sliding - of the top staves. Assured as we were of having stiff clay from 33 - to 37 feet, with what confidence we might have looked to making 18 - feet per week. There would be no difficulty in having accomplished - it. We must not look back, but overcome all difficulties! - - [Sidenote: Isambard on duty several successive nights.] - - _January 16._--Isambard having been up several successive nights, - went to bed at ten, and slept till six the next morning. I am very - much concerned at his being so unmindful of his health. He may pay - dear for it. - - _February 2._--Work done to this day 405 feet 4 inches. - - _February 3._--I visited the works; and, being in the cabin, I - complained of the dust there. _Dust under the Thames!_ - - _February 26._--I went to the Tunnel. The arch being well lighted - up, and the whole walk completed, a few visitors were admitted. The - coup d'oeil was splendid. Mrs. Brunel, Emma, Sophia and her three - little children were the first. It gave me great pleasure to see - the whole of my family in the new scene. - - _March 21_.--There being no clay above us, there is much to - apprehend from the springs. It would be much better to work slower - than we do. It is indeed very hard to be under the necessity of - driving. Anxiety increasing daily. - - [Sidenote: No clay above head; should work slower.] - - [Sidenote: Water increasing daily.] - - _March 28_.--The top pumps failed; the water rose above the - abutting screws. The frames of some of them could not be advanced, - nor could the bottom brickwork be laid down--great source of - complaint. Isambard called the men in at 10 o'clock; they went on - cheerfully. It is surprising that the men are so steady. - - [Sidenote: Our situation is getting much worse daily.] - - _March 29_.--Things are getting worse every day by the influx of - water; by which the ground is softened, and the operation rendered - extremely complicated and slow. As to the ground, it is evident we - are now as Isambard found it by his borings of August last. We have - nothing above our heads but clayey silt, and it is of a nature to - be detached and run into mud by the action of water. - - _April 3_.--The pumping now requires forty hands. There is no - exaggeration in saying that the influx of water, and the badness of - the ground, cause an extra expense of 150_l_. a week. - - [Sidenote: Obstacles in every way.] - - _April 7_.--It may now be said that we are contending with the - elements above and around, gaining and disputing every inch that we - add to the structure. - - _April 9_.--Isambard's birthday, he being of age to-day. - - _April 14_.--Doing as well as can be expected from the nature of - the ground, and the difficulties that increase upon us. - - [Sidenote: To be obliged to drive too fast is a sad alternative.] - - _April 18_.--The faces are found extremely tender; but having - proceeded with great caution, no accident occurred. None, I feel - confident, would occur if all idea of piece-work were abandoned. It - always operates as a stimulant, a very dangerous one. Obliged to - drive on, on account of expense, we run imminent risks indeed for - it. That a work of this nature, under such circumstances, should be - thus carried on, is truly lamentable. It is obvious that the clay - we have above our heads has been broken, by the ground beneath it - running or breaking in upon us. We shall have to fight it out until - we have a stronger or thicker stratum of clay. Sad prospect indeed - it is for us! - - _April 20_.--The ground at No. 1 broke in again, and occasioned - great delay. Some bones and china came down. - - _April 22_.--The diving-bell being on the spot, and Isambard having - moored it over the shield, he and Gravatt[17] descended at thirty - feet water. They found the same substances which had come through - the ground into the Tunnel. When Isambard was in the bell, he drove - a strong rod into the ground. Nelson, who was in the frame, heard - the blows. - - [Sidenote: A dreadful panic.] - - _April 29_.--Ground improving as we advance; we are not, however, - free from danger: a dreadful alarm took place this morning. While - Isambard and Gravatt were at breakfast, the porter came running in, - and exclaiming, 'It is all over! The Tunnel has fallen in, and one - man only has escaped.' Gravatt was the first to get to the spot, - and found all the pumpers upon the floor of the shaft, all - stupefied with horror, though every one was there quite safe, and - no rush of water was heard. Gravatt and Isambard were soon in the - shield, where they observed that a small portion of clay had fallen - from the top on the top floor. - - _May 8_.--At half-past three in the morning, an irruption took - place, bringing down the deposits of the bottom of the river--lumps - of clay, stones, bones, wood, nails, &c., &c., with water. The - pumpers and men on the stage (Irish) all ran away, some exclaiming, - 'The Thames is in! The Thames is in!' Ball and Rogers stood to - their post, and soon stopped this most formidable attack. - - _May 10_.--Great difficulties present themselves, that oppose our - progress; the chief, however, is the lodgment of water above our - heads. There it loosens the silt or sand, and runs out, leaving - cavities that cause the clay above to break, and run down in lumps - and disturbed streams. This is very awful! This opens the way for - the river. - - [Sidenote: Consequences of want of care more terrific and - mischievous than any preceding ones.] - - _May 12_.--In moving No. 6, they left by some unaccountable neglect - the top staves behind, and in that state two top polings were taken - down. The ground being very bad, and high water at the same moment, - the ground began swelling. Attention was called to several points, - and Gravatt continued in No. 6. He drew out at the front of the top - staves a shovel, and also a hammer, that had come through the - ground above. They are the same which Isambard left at the bottom - of the river, when he went down in the diving-bell. - - [Sidenote: Triumph of the shield.] - - _May 13_.--Notwithstanding every prudence on our part, a disaster - may still occur. _May it not be when the arch is full of visitors!_ - It is too awful to think of it. I have done my part by recommending - to the directors to shut the Tunnel. My solicitude is not lessened - for that: I have indeed no rest, and I may say have had none for - many weeks. So far the shield has triumphed over immense obstacles, - _and it will carry the Tunnel through_. During the preceding night - the whole of the ground over our heads must have been in movement, - and that too at high water. The shield must have therefore - supported upwards of _six hundred tons_: it has walked for many - weeks with that weight twice a day over its head. What flippancy - and inconsistency in some individuals, who, without any knowledge - of the subject, without so much as examining the state of the work, - will without the least reflection and hesitation obtrude their - suggestions upon every case. What shallow conceit for such to - pretend they can know better than those that have already the - experience that must result from years of deep thought, from days - and nights of incessant attention; who have the advantage of the - combined talents of several ingenious men, who devote their - undivided study, the whole resource of their well-stored minds, to - the enterprise; and to add to this, the benefit of the skill of one - hundred miners and excavators. Among this class of men, some have - been employed in the most perilous enterprises, when each - individual must have acted upon his sole judgment, where, in fact, - there is no room for an engineer to instruct and direct their - efforts. How easy it is to attack everything, to detract from the - merits of the best plan. There is always some weak point which may - be open to the penetration of the shallowest mind. Then comes the - exulting expression, _That I always said would never do, &c.,_ and - all the consequences with it. - - [Sidenote: How easy to detract.] - - _May 15_.--The water increased very much at 9 o'clock. This is - _inquietant_! My apprehensions are not groundless. I apprehend - nothing, however, as to the safety of the men, but first the - visitors, and next a total invasion by the river. We must be - prepared for the worst. I have had no rest for many weeks on this - apprehension. Should it occur we must make the best of it, by - improving our situation. - - _May 17_.--There is no doubt of the ground having improved very - materially since last Saturday. Very cheering indeed. - - _May 18_.--Visited by Lady Raffles and a numerous party. Having had - an intimation by Mr. Beamish of their intended visit, I waited to - receive and to accompany them, not only from the interest I felt at - being acquainted with Lady Raffles, but also from motives of - solicitude, knowing that she intended to visit the frames. Indeed, - my apprehensions were increasing daily. I had given some - instructions for enquiring where we could obtain clay, that we - should have some barges full of clay to be in readiness. I was most - anxiously waiting for the removal of the tier of colliers that was - over us, being convinced that we should detect some derangement - then. I attended Lady Raffles and party to the frames, most uneasy - all the while, as if I had a presentiment, not so much of the - approaching catastrophe to the extent it has occurred, but of what - might result from the misbehaviour of some of the men, as was the - case when the Irish labourers ran away from the pumps and the - stage. I left the works at half-past five, leaving everything - comparatively well: Mr. Beamish continued on duty.[18] - - Mr. Gravatt's account is as follows: I was above with I. Brunel - looking over some prints, Beamish being on duty. Some men came - running up and said to Isambard something I did not hear. He - immediately ran towards the works, and down the men's staircase. I - ran towards it, but could not get down. I leaped over the fence, - and rushed down the visitors' stairs, and met the men coming up, - and a lady, who I think was fainting. Met Flyn on the - landing-place, who said it was all over. I pushed on, calling him a - coward, and got down as far as the visitors' barrier. Saw Mr - Beamish pulled from it. He came on towards the shaft walking. I - went up to him to ask him what was the matter. He said it was no - use resisting. The miners were all upon the staircase; Brunel and I - called to them to come back. Lane[19] was upon the stairs, and he - said it was of no use to call the men back. We stayed some time - below on the stairs, looking where the water was coming in most - magnificently. We could still see the farthest light in the west - arch. The water came upon us so slowly that I walked backwards - speaking to Brunel several times. Presently I saw the water pouring - in from the east to the west arch through the cross arches. I then - ran and got up the stairs with Brunel and Beamish, who were then - five or six steps up. It was then we heard a tremendous burst. The - cabin had burst, and all the lights went out at once. There was a - noise at the staircase, and presently the water carried away the - lower flight of stairs. Brunel looked towards the men, who were - lining the staircase and galleries of the shaft, gazing at the - spectacle, and said, 'Carry on, carry on, as fast as you can!' Upon - which they ascended pretty fast. I went up to the top and saw the - shaft filling. I looked about and saw a man in the water like a - rat. He got hold of a bar, but I afterwards saw he was quite spent. - I was looking about how to get down, when I saw Brunel descending - by a rope to his assistance. I got hold of one of the iron ties, - and slid down into the water hand over hand with a small rope, and - tried to make it fast round his middle, whilst Brunel was doing the - same. Having done it he called out, 'Haul up.' The man was hauled - up. I swam about to see where to land. The shaft was full of casks. - Brunel had been swimming too. - - The first alarm, as I heard it, was as follows: Goodwin, in No. 11, - said to Roger, in the next box, 'Roger, come, help me.' Roger said, - 'I can't, I have my second poling down, and my face will run in.' - In a little time Goodwin said, 'You must come,' which Mr. Beamish - directed him to do. Roger turned round and saw Goodwin through a - sheet of water. Corps, a bricklayer, went to help Goodwin: he was - knocked down. Roger made his way alone, calling to Mr. Beamish, - 'Come away, sir, 'tis no use to stay.' Roger saw Corps fairly - washed out of his box like a lump of clay. - -Sir Isambard's journal continues:-- - - _May 19._--Relieved as I have found myself, though by a terrible - catastrophe, of the worst state of anxiety, that which I have been - in for several weeks past, I had a most comfortable night. Isambard - and Gravatt descended with the diving-bell, and stood upon the - tails of Nos. 10, 11, and 12. - - _May 20._--Having descended into the hole and probed the ground, I - felt that the staves were in their places, and that the brickwork - was quite sound. It is evident that the great hole has been a - dredging spot. A large mass of bags full of clay, and united - together with ropes, was let down. The Rotherhithe curate, in his - sermon to-day, adverting to the accident, said it was a fatal - accident, that it was but a just judgment upon the presumptuous - aspirations of mortal men, &c.! The poor man! - - _May 23._--Went with the diving-bell to examine the ground and the - bags, which do apparently well, but it is working rather in the - dark. It cannot, however, fail of making a much better stratum than - that we had before. The plan is therefore good. - -On the 30th a raft was sunk over the shield, and the water in the shaft -was brought so low that the last flight of steps was visible. However, -on the next day the river broke in again; and as it was found that the -raft was open at the west side, it was raised and towed on shore. - - _June 5._--There is much danger in getting out of the diving-bell, - the bags are so loose in some places. One might sink and be - swallowed, which had very nearly happened to-day. Isambard and - Pinckney being down, the latter lost his hold. The footboard being - accidentally carried away, he could not have recovered himself had - not Isambard stretched out his leg to his assistance. - - _June 17._--Visited by Charles Bonaparte. Isambard took him into - the arch with the yawl. Isambard fell overboard.[20] - -On June 19, a general meeting of the proprietors was held, to consider -the position of the company. Sir Isambard addressed the meeting, and -also presented a long report, in which he entered very fully into the -circumstances of the recent accident and the causes which led to it. He -then described the means he had taken to restore the works by sinking -bags of clay and gravel. He adds: 'I have already succeeded in closing -the hole through which the water first penetrated, and feel confident -that the second opening which afterwards appeared is also stopped, but a -short time is necessary to elapse for the new ground over the shield to -settle and consolidate. It has already supported a head of water of -thirty-five feet.' - - _June 25._--At 7 P.M. made preparations to re-enter the shield. - Isambard, mustering the men who had been the last to quit the - frames, told them they would be the first to take possession of - them again--a precedence due, as he said, to them. Rogers, Ball, - Goodwin, Corps, and Compton, were accordingly ordered to trim - themselves for the expedition, provided with a phosphorus box, and - dressed in light clothes, to be fit for a swim. - - At about ten o'clock, Isambard and Mr. Beamish, accompanied by Ball - and Woodward (miners), went down with the punt, and got to the - large stage, the head of the crane just emerging. It was found - impossible to get into the frames, as a mound of clay and silt - closed the entrance. The centering was in place and quite sound, - and of course the brickwork. Finding that they could not get - nearer, they gave three cheers, which were rapturously answered by - the men at the mouth of the Tunnel. Having placed candles upon the - ground that closed the entrance, and upon the head of the crane, - they returned. Isambard, having promised that the men who had left - the frames last should be the first to re-enter, returned with - them. This is a great day for our history! - - _June 27._--Mr. Beamish was able to get to the frames, which he - found firm and undisturbed. - -A small tarpaulin was now spread over the frames, and operations -commenced for cleaning them. This was a most difficult and dangerous -work, especially as the water was still so high that the frames could -only be approached by boats. The men, even the best hands, were at first -greatly alarmed at the danger they were in; but the example set by Mr. -Brunel and Mr. Beamish produced, as Sir Isambard notes, the best effect, -and they soon became reconciled to their situation. - - _July 7._--Very uncomfortable in the frames; the candles cannot - burn, the ventilation cannot act. Isambard went several times - to-day down in the diving-bell. On one occasion the chain slipped - through the stoppers, but most providentially it jammed itself - tight before being altogether run out. _The consequence might - indeed have been fatal._ Can there be a more anxious situation than - that which I am constantly in? Not one moment of rest either of - mind or body. Mr. Beamish always ready. Poor Isambard always at his - post too, alternately below, or in the barges, and in the - diving-bell. - -On July 11, Sir Isambard thought that matters had so far advanced that a -large tarpaulin, which it was proposed to sink over the frames, 'would -have its full effect.' It was accordingly sunk on the following day, -under the superintendence of Mr. Brunel. Sir Isambard adds to his -account of the operation--'This reflects great credit on Isambard, and -the apparent facility with which it was effected evinces his presence of -mind, for a single _faux pas_ would have spoilt the whole.'[21] - - - _July 21._--During the early part of the night an alarm was given, - by Fitzgerald calling for clay wedges, and exclaiming that the - whole of the faces were coming in altogether. Rogers collected a - quantity of wedges to go to the frames, but no boat was to be seen. - He called to the men in the frames, but received no answer. Taking - the small boat in the east arch, he reached the frames, but found - nobody, nor any appearance of derangement in the ground. - Conjecturing they might be drowned, he explored further, and saw - the four men stretched on the small stage, not drowned, but sound - asleep! - - _July 26._--Water nearly out of the arches. For the first time we - could walk to the frames--a most gratifying circumstance indeed! - _Two months and eight days._ - - _September 30._--How slow our progress must appear to others; but - it is not so, if it is considered how much we have had to do in - righting the frames and in repairing them; what with timbering, - shoring, shipping and refitting--all these operations being in - confined situations, the water bursting in occasionally, and the - ground running in: in short, it is truly terrific to be in the - midst of this scene. If to this we add the actual danger, magnified - by the re-echoing of the pumps, and sometimes (still more awful - warning!) the report of large pieces of cast iron breaking, it is - in no way an exaggeration to say that such has been the state of - things. Nevertheless, my confidence in the shield is not only - undiminished--it is, on the contrary, tried with its full effect, - and it is manifest now that it will soon replace us in good - ground, and in a safe situation. No top staves have given way. That - is our real protection. - - _October 17._--At 2.15 A.M. Kemble, having first called upon - Gravatt, came to Isambard in a hurry, and, quite stupefied with - fright, told him that the water was in. Says Isambard--'I could not - believe him. He said it was up the shaft when he came. This being - like positive, I ran without a coat as fast as possible, giving a - double knock at Gravatt's door in my way. I saw the men on the top, - and heard them calling earnestly to those whom they fancied had not - had time to escape. Nay, Miles had already, in his zeal for the aid - of others, thrown a long rope, and was swinging it about, calling - to the unfortunate sufferers to lay hold of it, encouraging and - cheering those who might not find it, to swim to one of the - landings. I immediately, I should say instantly, flew down the - stairs. The shaft was completely dark. I expected at every step to - splash into the water. Before I was aware of the distance I had - run, I reached the frames in the east arch, and met there - Pamphillon, who told me that nothing was the matter, but a small - run in No. 1 top, where I found Huggins and the _corps d'elite_. - They were not even aware that any one had left the frames. The - cause of the panic was one of the labourers; hearing the man in No. - 1 call for Ball, he ran away, jumping off the stage, crying, "_Run, - run, murder, murder; put the lights out._" His fellow-labourers - followed like sheep, making the same vociferations.' - - _November 10._--Isambard gave his entertainment to nearly forty - persons, who sat at table in the Tunnel. Nothing could exceed the - effect for brilliancy. About 120 men partook of a dinner in the - adjoining arch. - -As the year drew to a close, the difficulty of working the silt -increased, and with this difficulty increased also the expense of -maintaining the staff of men required. On December 18, Mr. Brunel, -writing for his father, who was absent from town for a few days, thus -describes the nature of the soil through which they were then passing. - - The state of the ground over Nos. 1, 2, and 3 top has caused - considerable delay, particularly this week, although not such as to - give any cause of anxiety as to our future rate of progress, or to - have any serious effect except the increased expense incidental to - this delay. My father desired me to describe to the Board the - causes of these difficulties. There is a considerable spring at - this point, and a corresponding soft part in the bed of the river, - which seems to indicate the rising of the spring. The ground in the - neighbourhood is affected by this spring in rather a peculiar - manner: at the half-flood tide the pressure is greatest: dry hard - clay oozes with great force through openings hardly observable, the - silt and water running by starts. At high-water the pressure and - quantity of water begin to diminish and on the ebb-tide the ground - is hard and dry, and can be worked with ease. On the flood-tide - there are as many as twelve and fifteen of the best hands, besides - myself (or one of my assistants) and the foreman, engaged entirely - at one face. - - -On January 1, 1828, Sir Isambard returned to London; and on the 12th, -when about 600 feet of the Tunnel had been completed, a second irruption -occurred, which put a stop to the works for seven years. - -The particulars of this accident are thus described by Mr. Brunel, in a -letter to the Directors of the Company:-- - - I had been in the frames (shield) with the workmen throughout the - whole night, having taken my station there at ten o'clock. During - the workings through the night, no symptoms of insecurity appeared. - At six o'clock this morning (the visual time for shifting the men) - a fresh set or shift of the men came on to work. We began to work - the ground at the west top corner of the frame: the tide had just - then begun to flow; and finding the ground tolerably quiet, we - proceeded by beginning at the top, and had worked about a foot - downwards, when on exposing the next six inches, the ground swelled - suddenly, and a large quantity burst through the opening thus made. - This was followed instantly by a large body of water. The rush was - so violent as to force the man on the spot, where the burst took - place, out of the frame (or cell) on to the timber stage behind the - frames. I was in the frame with the man, but upon the rush of the - water I went into the next box (or cell), in order to command a - better view of the irruption, and seeing that there was no - possibility of then opposing the water, I ordered all the men in - the frames to retire. All were retiring, except the three men who - were with me, and they retreated with me. I did not leave the stage - until those three were down the ladder of the frames, when they and - I proceeded about twenty feet along the west arch of the Tunnel. At - this moment the agitation of the air, by the rush of water, was - such as to extinguish all the lights, and the water had gained the - height of our waists. I was at that moment giving directions to the - three men, in what manner they ought to proceed in the dark to - effect their escape, when they and I were knocked down, and covered - with a part of the timber stage. I struggled under water for some - time, and at length extricated myself from the stage, and by - swimming and being forced by the water, I gained the eastern arch - where I got a better footing, and was enabled by laying hold of the - railway rope, to pause a little, in the hope of encouraging the men - who had been knocked down at the same time with myself. This I - endeavoured to do by calling to them. Before I reached the shaft - the water had risen so rapidly that I was out of my depth, and - therefore swam to the visitors' stairs, the stairs for the workmen - being occupied by those who had so far escaped. My knee was so - injured by the timber stage that I could scarcely swim, or get up - the stairs, but the rush of the water carried me up the shaft. The - three men who had been knocked down with me were unable to - extricate themselves, and I am grieved to say, they are lost; and I - believe also two old men, and one young man, in other parts of the - work. - -This statement Sir Isambard embodied in a report to the Directors of -January 28, which was circulated among the proprietors. - -As soon as the first excitement caused by the irruption had ceased, Mr. -Brunel directed the diving-bell to be prepared in order to ascertain the -state of the shield and the extent of the disturbance of the bed of the -river caused by the rush of water into the Tunnel. - -He was, however, so seriously injured that he could not actively -superintend the preparations, but his orders were given with his usual -clearness, calmness, and decision; and as soon as the barge containing -the diving-bell was properly moored over the Tunnel, he was carried out -and laid upon a mattress on the deck of the barge, that he might direct -what was to be done. - -As evening came on he became so much worse that he was taken into the -cabin; but everything which took place was reported to him. - -At length, the bell being ready, it was lowered early on the Sunday -morning, but the chain not being long enough, proceedings were delayed -until a longer chain could be obtained. - -As, however, a chain of the right size and length could not be obtained, -the strongest cable which could be procured in the neighbourhood was -substituted for the chain. A controversy then arose between the -assistant engineers and the foremen as to the sufficiency of the -strength of the cable; and it was agreed to consult and to abide by the -opinion of Mr. Brunel, who was then lying in great pain in the cabin. - -No answer could be obtained from him for some minutes, and then he only -said, 'Don't go down.' This not being satisfactory to the advocates of -the sufficiency of the cable, it was agreed to lower the bell empty, -which was done, and it was brought up safely; but just as it was swung -over the barge, the rope broke and the bell fell on to the stage. - -The next day Mr. Brunel was taken home, when it was found that, besides -the injury to his knee which he received while endeavouring to save the -lives of the three men who were with him,[22] he had received serious -internal injuries, which kept him under medical treatment for several -months. - -When he was able to return to Rotherhithe all hope of continuing the -works was for the time abandoned. When they were resumed, in 1835, he -was entirely engrossed in the independent pursuit of his profession; -and, with the exception of a few occasions when he acted for his father, -he had no further connection with the Tunnel. - -It is not, therefore, necessary to continue the narrative in detail; but -a brief summary of the subsequent history of the enterprise may be -interesting to those who are unacquainted with it. - -The Tunnel was cleared of water, and efforts were made, unfortunately -without success, to raise funds for the completion of the undertaking. -Great enthusiasm was exhibited by the general public and by many eminent -persons, including the Duke of Wellington; but the money was not -forthcoming, and nothing was left but to brick in the shield, and wait -for more favourable times. - -It was not till the beginning of 1835 that the Company was able, by the -aid of a loan from Government, to recommence the works. The old shield -was removed and a new one substituted, in which considerable -improvements were introduced. Slings connecting the frames were added, -which enabled each frame to support its neighbours when necessary, and -important alterations were also made in the arrangements for keeping the -frames at the right distance from one another, and for giving greater -facility of adjustment to the various parts. - -Before the Wapping side was reached there were three more irruptions of -the river, namely, August 23, November 3, 1837, and March 21, 1838; but -in October 1840 the shaft on the Wapping shore was commenced. It -differed from the Rotherhithe shaft, in being sunk the whole depth -without underpinning, and was made of a slightly conical form, to reduce -the friction in sinking, and had a larger quantity of iron hoops -introduced into the brickwork, in order to increase its strength. When -this structure had been sunk to the required depth (70 feet), the -excavation of the Tunnel was resumed, and at last the shield was brought -up to the brickwork of the shaft. The operation of making the junction -between the Tunnel and the shaft was one of much difficulty, but it was -at length satisfactorily accomplished, and the Tunnel was opened to the -public on March 25, 1843--eighteen years and twenty-three days after the -commencement of the work.[23] - -Sir Isambard Brunel, whose health had for some time been failing, now -retired altogether from his professional labours. After passing a few -years in peaceful and happy seclusion, surrounded by those he loved, and -watched over by their affectionate care, he died on December 12, 1849, -in his 81st year, having been spared to carry to completion his greatest -work, and to see his son following in his footsteps with a success which -must have exceeded his most sanguine expectations. - - * * * * * - -The education Mr. Brunel received from his father was well calculated to -form the foundation of his future career. During the later and more -arduous part of the contest, which was ended by the irruption of January -1828, he held both the nominal and actual post of Resident Engineer of -the Thames Tunnel; but from the commencement of the works, when he was -only nineteen years old, he had been, as stated by Sir Isambard, 'a most -valuable coadjutor in the undertaking.' While placed in this responsible -position he acquired habits of endurance and of self-reliance, and -learnt to act with promptitude and decision in the application of those -measures which experience had shown to be effective in each particular -class of emergency. But beyond all other advantages, he had before him -the example of his father's character, in which a rare degree of -gentleness and modesty of disposition was joined to unflinching energy, -and a determination to overcome all difficulties. - - -NOTE A (p. 5). - -_The Bourbon Suspension Bridges_.[24] - -The suspension bridges designed by Sir Isambard Brunel for crossing -rivers in the Ile de Bourbon were two in number. One of them had two -spans of 122 feet each in the clear, and 131 feet 9 inches between the -points of suspension of the chains. The second had but one span of the -same dimensions as those of the larger bridge. In the design of these -bridges one of the most important points to be attended to, was to -render them secure against hurricanes, which are both frequent and -severe in the Ile de Bourbon. - -In the larger bridge there was a pier of masonry, built in the middle of -the river up to the level of the roadway of the bridge. The suspension -chains of the bridge were in three groups, 9 feet 8 inches apart, so as -to leave room for two roadways, each about 8 feet 9 inches wide. Each of -these groups of chains consisted of two chains side by side. Each chain -was made with long links like those of the chain cables used for -moorings. - -These links, which were made of iron 1.36 inch in diameter, were 4 feet -8 inches long, inside measure, and were each connected together by two -short coupling links, 8-3/4 inches long, inside measure, of iron 1.36 inch -by 1 inch, and two pins, each two inches in diameter. - -The two chains of each group were placed side by side, with the links -upright; one of the pins at each joint was made long enough to serve for -both chains, and, in the middle of its length between the two chains, -was passed through an eye at the upper end of one of the suspending rods -of the bridge. Thus to every joint in each group of the main chains, or -at intervals of about 5 feet, there was a suspending rod. These rods -were 1-1/4 inch in diameter. - -The pins of the joints of the main chains had half heads at each end of -them. They could thus be easily inserted in erecting the bridge, but -once in place were quite secure. At every fourth joint in the main -chains one of the joint pins was made in two halves, with wedges -inserted between them for adjusting the length of the main chains. - -Thus there were six chains, and as the links of these had each two parts -of iron 1.36 inch in diameter, the total sectional area of the six -chains was 17.4 inches. - -Each group of the main chains was supported at a height of 25 feet 6 -inches above the roadway at the centre pier, and at a height of 5 feet 3 -inches at each of the side piers, the lowest portion of the curve of the -chain being about 1 foot below the points of suspension of the side -piers. - -The upright standards, carrying the chains both at the centre pier and -at the side piers, consisted for each group of chains of a triangular -framework of cast iron, strengthened by long bolts of wrought iron. -There were thus three of these triangular frames parallel to each other -at each of the piers, and those at the centre pier were braced together -over the carriage road. The main chains were not bolted to the -standards, but were slung from them by a vertical suspension link, which -thus allowed them to move a little lengthways. This link, in fact, -performed the function of the rollers now generally put under the -saddles of suspension bridges. - -The ends of the main chains were held by back stays, formed of bars 3 -inches broad by 1-1/4 inch thick, and 10 feet long, with joints made with -short links, and 2-3/8 inch pins. The ends of those back stays were -secured to holding down plates 3 feet in diameter, sunk deep in the -ground and well loaded. - -As there was a vertical suspension rod at each joint of the main chains, -there was a suspension rod hanging from each of the three groups of -chains at about every five feet of the length of the bridge. To each set -of these rods was attached a cross girder of cast iron of a =T= section, -with a large rounded bead at the lower edge of the upright web; and -connecting these under each of the main chains was a longitudinal timber -beam about 8 inches square. - -The cast-iron cross girders carried longitudinal teak planking, the -planks on which the carriage wheels ran being 12 inches wide and 4 -inches thick, protected at the top by wrought-iron plates running -longitudinally. The horse-path was protected by iron plates arranged -crosswise. - -Under each span of the bridge were four chains curved upwards and also -sideways. These chains were fastened at their ends into the piers, and -were connected to the roadway by ties drawn up tight and attached to the -main longitudinal bearers of the platform; the object being to stiffen -the platform. - -These under tie chains were made each of a set of rods 1-1/4 inch in -diameter with eyes at their ends, the ends being connected by short -joint links and 1-1/4 inch pins; and to these joint links were attached the -tie rods which connect these inverted chains with the platform of the -bridge, and so prevented its being lifted or blown sideways by the force -of the wind. - -In the smaller bridge, which, as has been said, consisted of one span of -131 feet 9 inches between the points of suspension, these points were 15 -feet 5 inches above the roadway, and the lowest part of the chain was 9 -feet 7 inches below the points of suspension. The details of this bridge -were similar to those of the larger one. - - -NOTE B (p. 5). - -_Experiments with Carbonic Acid Gas._ - -In 1823 Mr. Faraday made the important discovery that under certain -conditions of temperature and pressure many gases could be liquefied, -and that these liquids exerted great expansive force by slight additions -of temperature, returning quickly with regularity and certainty to their -original state upon the application of cold. - -The discovery of this new force appeared of such importance, that Mr. -Faraday lost no time in publishing it to the world; and Sir Isambard -Brunel very soon afterwards commenced a series of experiments to -determine the value of the liquid gas as a mechanical agent. - -The first experiments were made at Chelsea; but the prosecution of them -was soon transferred to the care of Mr. Brunel at Rotherhithe, where he -devoted all his spare time to the construction of his father's proposed -'Differential Power Engine.' - -That the progress of this discovery, and of the experiments made with a -view to the application of the liquid gas, as a motive power, may be -understood, it is necessary to state that in March 1823 Mr. Faraday -communicated to the Royal Society the results of his first experiments -on the liquefaction of gases. - -The fluid was then produced by the decomposition of the hydrate of -chlorine by heat in a closed tube, the amount of gas evolved being so -great as to produce a pressure in the tube sufficient to condense the -gas into a fluid of the same volume. - -This interesting experiment was followed by others with that rapidity -and success so remarkable in everything undertaken at that time in the -laboratory of the Royal Institution; and within a month another paper -was read before the Royal Society, in which the degrees of pressure and -temperature at which several gases could be liquefied were recorded, and -the means employed to produce and liquefy each gas accurately described. - -On April 17 a third paper was communicated by Mr. Faraday, 'On the -Application of Liquids produced by the Condensation of Gases as -Mechanical Agents.' - -The question is thus stated: 'The ratio of the elastic force dependent -upon pressure is to be combined with that of the expansive force -dependent on temperature; and the development of latent heat on -compression and the necessity of its reabsorption in expansion must -awaken doubts as to the economical results to be obtained by employing -the steam of water under very great pressures and very elevated -temperatures. - -No such doubt can arise respecting liquids, which require for their -existence even a compression equal to thirty or forty atmospheres, and -where slight elevations of temperature are sufficient to produce an -immense elastic force, and where the principal question arising is -whether the effort of mechanical motion is to be most easily produced by -an increase or diminution of heat by artificial means.' - -Difficulties were suggested by Mr. Faraday as to the possibility of -obtaining sufficient strength in the apparatus, but the small difference -of temperature required to produce an elastic force of many atmospheres, -he considered would render the risk of explosion small. - -To construct the machinery whereby this new force could be practically -applied as a substitute for steam, occupied the time of Sir Isambard -Brunel and his son at intervals for several years; for although Mr. -Brunel was satisfied at an early period of the enquiry that the -liquefied gases could only be advantageously employed where the cost of -motive force was secondary to economy of space and to the avoidance of -the cumbrous apparatus required for the use of steam, still he was so -impressed with the importance of the subject, if the difficulties he -foresaw in its application could be overcome, that he continued his -experiments for a long period with unflagging energy and perseverance. - -The facts relating to the liquefaction of the gases, their elastic force -when liquefied under different temperatures, the rapidity with which -they could be alternately expanded and condensed, and the best mode of -producing each gas, were determined by Mr. Faraday; and as Mr. Brunel -was at that time attending the morning chemical lectures at the Royal -Institution, he was in constant communication with him, and thoroughly -conversant with his experiments. - -After Mr. Brunel had made a few preliminary experiments, Sir Isambard -determined to employ liquefied carbonic acid gas for the motive power of -the proposed new engine, the facility and cheapness of its production, -its great expansive force, and its neutral character distinguishing it -from any other gas; but it was long before vessels were constructed, in -which gas could be produced in sufficient quantity and purity to exert -the force required to liquefy it in its own volume, for it was soon -found to be impossible to obtain the required pressure with pumps. - -Carbonate of ammonia and sulphuric acid were the elements used, and the -generator was so arranged that it could be charged, emptied of -atmospheric air, and the joints made perfect, before the commencement of -the formation of the gas which was to be liquefied. - -To the generator was attached a receiver, which could be surrounded with -a freezing mixture, so that the temperature of the gas in the cylinder -might be below that in the generator. - -The gradual formation of the liquid, the development of its elastic -force, and the regularity and rapidity with which it increased or -diminished by each degree of heat or cold, were carefully watched -through a glass gauge, and the receiver when filled with liquid could be -disconnected from the generator. - -The mechanical difficulties as they arose, one after the other, in the -construction and arrangement of the various parts of the generator and -receiver were at length overcome; and the receiver was not only filled -with liquid gas, but found to be capable of retaining it, whether -exerting an elastic force of 30 atmospheres at ordinary temperatures, or -of 100 atmospheres when subjected to a slight degree of heat. - -The receiver being satisfactorily completed, the next object of -attention was the design and construction of a working cylinder capable -of resisting at least 1,400 lbs. pressure on the square inch; a task -which was one of great anxiety, as any weakness might have caused a -serious accident. - -It was only after the trial of every known method of making joints to -resist high pressures had failed, that an arrangement was devised, -requiring the most perfect workmanship, by which packing of any kind was -dispensed with, and the cylinder fitted for use. - -With the improved tools of the present day it is not easy to realise the -difficulties, delays, and disappointments which forty-five years ago -occurred from the failure, first of one part of a joint, and then of -another; but the construction of vessels capable of producing and also -of retaining the gas in its liquid state, with the means of alternately -expanding and condensing it from thirty or forty to eighty or one -hundred atmospheres, having been accomplished, the object of the -expenditure of so much labour and inventive power appeared to be within -reach. - -The construction of the machinery to utilise the elastic force contained -in the cylinder was now proceeded with. Day by day new difficulties -arose, and each as it was successfully met seemed but to leave another -of greater importance to be surmounted. - -It is not necessary in this Note to describe the various arrangements -which were devised for transferring the great elastic force in the -cylinder of small diameter to a piston in another cylinder of much -larger dimensions; it is sufficient to say, that after the devotion of -much valuable time extending over several years, and a very large -expenditure of money, and after carefully considering the cost of the -liquid carbonic acid gas, the difficulty of preventing waste, and the -necessarily very expensive character of the machinery, Mr. Brunel was -satisfied 'that no sufficient advantage in the sense of economy of fuel -can be obtained by the application of liquefied carbonic acid gas as a -motive power'; but so thoroughly did he exhaust the subject before he -committed himself to this opinion, that no one has since renewed the -enquiry or attempted to make a machine to be moved by the elastic force -of liquefied gases, the construction of which, it was well known, had -baffled the inventive genius of Sir Isambard Brunel and his son. - - - - -CHAPTER II. - -_THE CLIFTON SUSPENSION BRIDGE._ - -A.D. 1829--1853. AETATIS 24--48. - - ORIGIN OF THE UNDERTAKING--THE FIRST COMPETITION, NOVEMBER - 1829--DESCRIPTION OF MR. BRUNEL'S PLANS--MR. TELFORD'S DECISION AS - UMPIRE--MR. TELFORD'S DESIGN--THE SECOND COMPETITION--MR. BRUNEL - APPOINTED ENGINEER, MARCH 1831--COMMENCEMENT OF THE WORKS, AUGUST - 1836--DESCRIPTION OF THE DESIGN--ABANDONMENT OF THE WORKS, - 1853--FORMATION OF A NEW COMPANY AND COMPLETION OF THE BRIDGE, - 1864. _NOTE_: THE HUNGERFORD SUSPENSION BRIDGE. - - -After Mr. Brunel had recovered from his accident in the Thames Tunnel, -he went for a trip to Plymouth, where he examined with great interest -the Breakwater and other engineering works in the neighbourhood. He -notes in his diary that he went to Saltash, and that he thought the -river there 'much too wide to be worth having a bridge.' This remark was -no doubt made in consequence of his father having some years before been -consulted as to the construction of a suspension bridge at this place, -which Mr. Brunel himself, eighteen years afterwards, selected for the -crossing of the Tamar by the Cornwall Railway, and built there the -largest and most remarkable of his bridges. - -For the remainder of the year 1828, and during the greater part of 1829, -Mr. Brunel kept himself fully employed in scientific researches, and in -intercourse with Mr. Babbage, Mr. Faraday, and other friends; but he was -without any regular occupation, until, in the autumn of 1829, he heard -that designs were required for a suspension bridge over the Avon at -Bristol, and he determined to compete. - -This project originated in a bequest made in 1753, by Alderman William -Vick, of the sum of 1,000_l._ to be placed in the hands of the Society -of Merchant Venturers of Bristol, with directions that it should -accumulate at compound interest until it reached 10,000_l._, when it was -to be expended in the erection of a stone bridge over the river Avon, -from Clifton Down to Leigh Down. Alderman Vick stated that he had heard -and believed that the building of such a bridge was practicable, and -might be completed for less than 10,000_l._ - - * * * * * - -The legacy was duly paid to the Society of Merchant Venturers, and -invested by them. The interest accumulated; and in 1829, when the fund -amounted to nearly 8,000_l._, a committee was appointed to consider in -what way it would be possible to carry out Alderman Vick's intentions. - -An estimate for a stone bridge was procured, but as it gave the cost at -90,000_l._, it was evident that this scheme must be abandoned. - - * * * * * - -The committee then advertised for designs for a suspension bridge. Mr. -Brunel, on hearing through a friend of the proposed competition, went to -Bristol; and, after examining the locality, he selected four different -points within the limits prescribed by the instructions of the -committee, and made a separate design for each of them. His plans were -sent in on the day appointed, Nov. 19, 1829, with a long statement, from -which the following description of them is taken. - -The first design was for a bridge of 760 feet span between the points of -suspension, the length of the suspended floor being 720 feet. In order -to obtain a height of 215 feet above high-water mark (which was the -least that the levels allowed of), towers 70 feet high would have had to -be built on the cliffs to carry the chains. The total length of chain, -including the land-ties, was about 1,620 feet. Mr. Brunel did not -approve of this design, as the situation was not favourable to -architectural effect, a point to which the committee attached great -importance; but he suggested it from its being somewhat more economical -in construction than his other plans. - -In another design, the situation being some way farther down the river -than that of the design last mentioned, towers would also have been -necessary. The distance between the points of suspension was 1,180 feet, -with a suspended floor of over 900 feet. It is probable that Mr. Brunel -only proposed this plan because the site came within the limits of -deviation, as he does not say anything in favour of it in his report. - -The two remaining plans are the most interesting of the series, as there -can be no doubt that, if Mr. Brunel had had his own way, he would have -adopted one of them for execution; and it appears from a little sketch -on the top of one of his earliest letters from Bristol, that his first -idea for the bridge was that which is carried out in these two designs. -The site selected was one where the rocks rise perpendicularly for a -considerable height above the proposed level of the bridge, and -therefore piers and land-ties were dispensed with, the chains being hung -directly from the rock. No masonry was required except for architectural -effect.[25] - -[Illustration: CLIFTON SUSPENSION BRIDGE. - -Plate I. - -Fig. 1. - -Elevation of Drawing Nº 3 of Mr. Brunel's Designs in the first -competition. AD. 1829 - -Fig. 2. - -H. Adlard So. - -Elevation of the Bridge according to the Design on which the works were -commenced. AD. 1836.] - -The principal difference between these two designs is that in the second -a short tunnel is avoided at one end. The style of architecture selected -for the tunnel-front and the face of the rock, as shown on the drawings -sent in to the committee, is Norman. There are also extant many -beautiful sketches made by Mr. Brunel for different parts of the -design.[26] - -In determining upon the mode of construction, which was the same in the -four designs, Mr. Brunel acted upon the principle which guided him in -all his subsequent undertakings, which was, as he states in his report, -'to make use of all that has been found good in similar works, and to -avail himself of the experience gained in them, and to combine with all -their advantages the precautions which time and experience had pointed -out.' - -He dismissed in a few words the plan of breaking the span into two or -three lengths. This was in his opinion unnecessary, and he computed that -the cost of a pier built up from the water's edge to sufficient height -above the bridge to carry the chains, would be at least 10,000_l._ For -this reason he recommended the adoption of spans, the smallest of which -far exceeded any up to that time constructed. - -In designing the chains, he dispensed with the short connecting links, -which had been previously adopted in suspension bridges, introducing -instead the method now universally used, of connecting each set of links -directly with the adjoining one by means of a pin passed through the -holes of both. The number of joints and pins was thus reduced one half, -and a considerable saving of expense, as well as diminution of weight, -effected. - -Another improvement, which diminished still further the weight of the -chains, was making the links in lengths of 16 feet, or nearly double -that of the longest links at the Menai bridge. The chief reason for this -alteration was to ensure a near approximation to equality in the strains -on the different links, should all the distances between the holes not -be exactly equal. This improvement was afterwards carried still further -in the Hungerford Suspension Bridge, the links of which were 24 feet -long.[27] - -Mr. Brunel also intended to introduce equalising beams in the supports -of the floor, so that each chain should bear an equal share of the load. -By this arrangement, there would have been comparatively few points of -suspension, and 'the view of the scenery would not be impeded from the -observer being surrounded by a forest of suspension rods.' - -The disturbance of the strains on the links arising from the greater -expansion of the metal of the outer links by the direct heat of the sun, -he proposed to obviate by sheet-iron plates placed on each side of the -chains, but separated from them by a small interval, and thus screening -them from the heat. He did not, however, use this protecting covering at -the Hungerford bridge. - -All the designs show a camber or rise in the centre of the platform of -the bridge, to the extent of two or three feet; and the main chains are -brought down almost to the level of the platform. To this last -arrangement, as tending to prevent undulation, Mr. Brunel attached some -importance; and he further intended to stiffen the bridge against the -action of high winds by a system of transverse bracing, and by the -addition of inverted chains, similar to those used with success by his -father in the Bourbon bridges.[28] - -Such, then, were the main features of the bold and carefully matured -designs placed by Mr. Brunel before the committee. Out of twenty-two -plans submitted, only those of Mr. Brunel and four other competitors -were deemed worthy of consideration. He and his friends were naturally -much gratified at this, and were full of hope for his ultimate victory. -But now, when he seemed to have a fair chance of success in a contest -which he justly deemed would have a most important bearing upon his -future professional career, an obstacle presented itself, which for the -time seemed almost insurmountable; for he met with an unexpected -opponent in Mr. Telford, the foremost engineer of the day, and the -designer of the famous suspension bridge over the Menai Straits. - -The committee of the Society of Merchants had, not unnaturally, found -themselves unable to decide upon the merits of designs for a suspension -bridge, and had asked Mr. Telford to act as their adviser in the matter. -Unfortunately for Mr. Brunel, Mr. Telford was of opinion that the -maximum span admissible was that of the Menai bridge, _i.e._ under 600 -feet, and that Mr. Brunel's proposed bridge, though very pretty and -ingenious, would most certainly tumble down in a high wind. - -This decision was, of course, fatal to the success of any design which -substituted one large span for two or more smaller ones, and dispensed -with pillars. Mr. Brunel therefore obtained permission to withdraw his -plans from the competition. - -Mr. Telford then reported to the committee that none of the remaining -designs were suitable for adoption without the introduction of such -material alterations as would, in fact, constitute a new design. -Whereupon the committee took the only course which, under the -circumstances, was open to them, and requested Mr. Telford to prepare a -design himself. - -Mr. Brunel was not a little disappointed at the turn matters had taken; -but, having, as he said,'smoked away his anger,' he took leave of his -friends at Bristol, and went for a visit to some of the principal -manufacturing towns in the north. - -Meanwhile Mr. Telford prepared his design, and it was exhibited in -Bristol in January 1830. It consisted of a suspension bridge of three -spans (the centre span 360 feet, and the side ones 180 feet each), the -chains being supported at the intermediate points by tall stone piers -rising from the river's banks at just sufficient distance apart to avoid -interfering with the roadways on either side of the stream. The style of -architecture was a florid Gothic; and, in order to display the peculiar -features of that style, the faces of the piers were covered with -elaborate panelling, and the chains ornamented with fret-work. - -This design was received with a flourish of trumpets; numerous -engravings were published, exhibiting the bridge from various points of -view, and 'thousands of copies were disposed of;' but, after a time, it -would appear that the captivating effect of the Gothic belfries wore -off, and that the more the citizens of Bristol looked at Mr. Telford's -plan, the less they were satisfied with it; for, although it was -deposited in the Private Bill Office, on application being made for an -Act of Parliament, the trustees who were appointed under the Act -determined to invite a second competition. - -On this occasion, Mr. Telford appeared as a competitor and not as a -referee, that office being filled by Mr. Davies Gilbert, sometime -President of the Royal Society. - -The site of the bridge was fixed, being that selected by Mr. Telford; -but the trustees expressly left it to the judgment of the competitors to -decide whether there should be intermediate piers or one unbroken span. - -Of the thirteen designs sent in, five, including those submitted by Mr. -Telford and Mr. Brunel, were reserved for further examination. On March -17, 1831, Mr. Davies Gilbert (who had been assisted by Mr. Seward) made -his report. Mr. Telford's design was put aside, 'on account of the -inadequacy of the funds requisite for meeting the cost of such high and -massive towers as were essential to the plan which that distinguished -individual had proposed.' - -Mr. Brunel's design was placed second.[29] Although Mr. Gilbert reported -that it presented every desirable strength and security, he saw -objections to many of the details, and therefore did not recommend it -for adoption. However, on the following day, March 18, he stated to the -trustees that he had seen Mr. Brunel, and that it gave him much pleasure -to state that the explanations made by Mr. Brunel had materially altered -his views as to the details of the plans, which he (Mr. Gilbert) was now -satisfied were quite equal to those which he had placed first, and that, -considering the superiority of Mr. Brunel's design in the essential -particular of strength, he should judge it preferable to any of the -others. - -Thereupon the trustees, 'having considered Mr. Davies Gilbert's report, -and referred to all the plans, including Mr. Telford's, unanimously gave -the preference to Mr. Brunel's,' and appointed him their engineer. - -Subscriptions came in but slowly, and it was not till 1836 that the -works were commenced. - -The first stone of the abutment on the Leigh woods or Somersetshire side -of the river was laid on August 27 by the Marquis of Northampton, -President of the British Association, which was then holding its meeting -in Bristol.[30] - -The span of the bridge is greater than that of Mr. Brunel's design for -the second competition, but much less than the spans of the earlier -designs, to which he had given the preference.[31] On this point, as -well as on the question of site, he had to conform to the wishes of the -trustees.[32] The span approved of by them necessitated the building of -a very large abutment on the Leigh woods side, the height of which, from -the surface of the rock to the level of the roadway, is 110 feet. Above -the roadway, the tower to carry the chains is built to a height of 86 -feet. On the Clifton side, the base of the tower is formed by one of the -boldest of the range of St. Vincent's rocks, which here rise almost -perpendicularly to a height of 230 feet above high water, and -consequently a very small abutment was required. The tower on this side -is 3 feet higher than that on the Leigh woods side, and the roadway has -a general inclination of about 1 in 233. Mr. Brunel thought that if the -roadway were level, it would have the appearance of falling towards -Clifton, owing to the ground there being precipitous, while on the -Leigh woods side it is sloping. - -He intended, in the construction of the bridge, to have followed out the -ideas embodied in his report of 1829, and would have preferred to have -had only one chain on each side of the bridge, and that much stronger -than was usually adopted; but, in deference to public opinion, he put -two chains, though he doubted if they would expand equally. 'A rigid -platform would in some degree prevent the unequal distribution of load -thus caused, but he endeavoured to lessen the effect of unequal -expansion by arranging a stirrup at the top of each suspending rod, so -as to hold equally at all times on both chains, and thus to cause each -to sustain its proportion of the load.' - -The road platform was to have had beneath it 'a complete system of -triangular bracing, which would render it very stiff.' - -In order to lessen the action of wind on the bridge, he brought down the -main chains in the centre nearly to the level of the platform, and -intended to apply the system of brace chains at a small angle to check -vibration. There were, moreover, to be two curved chains lying -horizontally, and attached underneath the platform, so as to resist the -lateral action of the wind.[33] - -He here introduced movable saddles to carry the chains on the top of the -towers, with rollers running on perfectly flat and horizontal roller -beds.[34] By this arrangement no pressure except a vertical one could -come on the towers. - -He also devised means, by levers and hydraulic presses, for relieving -the rollers and roller beds from pressure, in the event of their -requiring renewal. - -Mr. Brunel ultimately determined to adopt the Egyptian style of -architecture. His brother-in-law, Mr. John Callcott Horsley, R.A., gives -the following account of the proposed designs for the towers:-- - -'His conception of the towers or gateways at either end of the bridge -was peculiarly grand and effective, as may be seen from his sketches -still existing. They were to be purely Egyptian; and, in his design, he -had caught the true spirit of the great remains at Philae and Thebes. He -intended to case the towers with cast iron, and, as in perfect -accordance with the Egyptian character of his design, to decorate them -with a series of figure subjects, illustrating the whole work of -constructing the bridge, with the manufacture of the -materials--beginning with quarrying the iron ore, and making the iron, -and ending with a design representing the last piece of construction -necessary for the bridge itself. The subjects would have been arranged -in tiers (divided by simple lines) from top to bottom of the towers, and -in the exact proportion of those found upon Egyptian buildings. He made -very clever sketches for some of these proposed figure subjects, just to -show what he intended by them. I remember a group of men carrying one of -the links of the chainwork, which was excellent in character. He -proposed that I should design the figure subjects, and he asked me to go -down with him to Merthyr Tydvil, and make sketches of the iron -processes. We accomplished our journey, and all the requisite drawings -for the intended designs were made.' - -The works were commenced with the Leigh abutment, which was completed in -1840, great delay having been caused by the failure of the contractors. -This misfortune led to a large excess of expenditure over the original -estimates. In 1843 the whole of the funds raised (amounting to -45,000_l._) were exhausted, and there still remained to be executed the -ornamental additions to the piers (the cost of which was estimated at -about 4,000_l._), half of the iron work, the suspension of the chains -and rods, the construction of the flooring, and the completion of the -approaches, &c., the estimate for the execution of which was 30,000_l._ - -Unfortunately, all efforts to raise further subscriptions were -unsuccessful; and in July 1853, when the time limited for the completion -of the bridge had expired, the works were closed in, and the undertaking -abandoned.[35] - -Several proposals for completing the bridge were made in Mr. Brunel's -lifetime, and he took every opportunity of furthering this object, which -he had very much at heart. It was not, however, till about a year after -his death that the superstructure of the bridge was actually commenced. - -A company was formed in 1860 by some of the principal members of the -Institution of Civil Engineers, 'who had an interest in the work as -completing a monument to their late friend Brunel, and at the same time -removing a slur from the engineering talent of the country.'[36] Mr. -John Hawkshaw, F.R.S., and Mr. W. H. Barlow, F.R.S., were appointed the -engineers, and Mr. Brunel's old friend Captain Christopher Claxton, -R.N., the secretary. The works were carried on with vigour; and the -bridge was opened with much ceremony on December 8, 1864. - -The chains were brought from the Hungerford Suspension Bridge, then in -process of demolition. A description of the Hungerford bridge will be -found in the note to this chapter.[37] - -Although the Clifton bridge was not completed by Mr. Brunel, his -connection with it forms a very important passage in the history of his -life. Doubtless, if he had never heard of the proposed competition in -1829, or if he had been one of the disappointed competitors, he would -have found some other opportunity of making a name in his profession; -but, as a matter of fact, the Clifton bridge competition did give him -the opportunity he desired, and all his subsequent success was traced by -him to this victory, which he fought hard for, and gained only by -persevering struggles. He never forgot the debt he owed to Bristol, and -to the friends who helped him there; and he would have greatly rejoiced -to see the completion of his earliest and favourite work. - -[Illustration: HUNGERFORD SUSPENSION BRIDGE - -H. Adiard Sc.] - - -NOTE (p. 58). - -_The Hungerford Suspension Bridge._ - -The suspension bridge which spanned the Thames at Charing Cross, on the -site of the present railway bridge, was designed and constructed by Mr. -Brunel between the years 1841 and 1845. It consisted of a centre span of -676 feet, and two side spans of 343 feet each. Being intended for foot -passengers only, its width was 14 feet. The versed sine, or deflection -of the middle of the catenary, was 50 feet. The two river piers, which -still exist up to the level of the railway, and form piers of the -present bridge, were of brickwork, with large footings at the bottom, so -as to distribute the pressure over a considerable area. The whole -structure was made hollow and as light as possible. From the level of -the footway the piers were carried up as ornamental campanile towers, -the weight of the chains being taken by four solid pillars of brickwork, -7 feet 3 inches square, forming the angles. Mr. Brunel introduced here -many of the arrangements he had designed for the Clifton bridge. In -order that the pressure from the chains might be always vertical on the -piers, the saddles rested on rollers working in oil, on the level -surface of a large cast-iron bed-plate. By this arrangement it was -rendered possible for the chains of the land spans to leave the tower at -a greater inclination than those of the middle span, so that the chains -were made shorter, and as they were at a lower level where they met the -abutment, there was less change in their direction at that point, and -consequently less thrust on the brickwork. Freedom of horizontal motion -was also secured, so that, in the case of unequal loading of the spans, -the chains might accommodate themselves to the strains, and move -horizontally until equilibrium was restored. At each of the land -abutments the chains passed down over a fixed saddle, at an inclination, -to anchorages placed at the bottom of the abutment. The brickwork under -the fixed saddle was so disposed as to resist directly the thrust -resulting from the change of direction between the main chains and the -anchor chains. To resist any movement of the abutments, the piles on -which they rested were driven obliquely, with their heads inclined from -the river. These piles were very numerous, the abutments spreading out -so as to cover a large area at the foundations. Nearly all the spaces -between the longitudinal, cross, and outside walls were filled with -concrete, in order that the abutments might be as massive as possible. -The details of the brickwork in the piers and abutments showed Mr. -Brunel's skill in the economical employment of this material. The chains -were constructed so that the sectional area was proportional to the -strain; the total area at the centre was 296 square inches, while near -the piers it was 312 square inches. There were four chains, two on each -side of the bridge, placed one above the other, and consisting each -alternately of ten and eleven links. The links were 24 feet long and 7 -inches in depth, the thickness varying so as to give the requisite -sectional area. - -The relative diameter of pin, and proper form of the ends of the link, -were subjects of much consideration, and many experiments were made in -order to determine these points. The fact that two specimens of iron, -apparently identical in every respect, sometimes exhibit considerable -difference in their breaking weights, shows that an average of a great -number of experiments is required in order to test satisfactorily any -proposed refinements of construction. Mr. Brunel, however, convinced -himself by experiment that he had practically arrived at such a form of -link and diameter of pin that the chain would have no tendency to break -at one point rather than another. The links were forged with shoulders -near the eyes, in order that by means of clamps the pin could be taken -out and the links disengaged, if necessary. - -The efficient action of the rollers was demonstrated shortly after the -completion of the bridge. On the occasion of the opening of the Corn -Exchange by Prince Albert, one of the land spans was crowded with -people, while the centre span was nearly empty. In consequence of this -the land chains became depressed considerably below their normal -position; and the saddles on the top of the tower nearest to the loaded -span moved horizontally on the rollers to the extent of 3 inches; and, -when the crowd had dispersed, they returned to their original position. - -Many years after the completion of the bridge a proposal was made to -widen it for carriage traffic; but this was not carried out, and -eventually the superstructure was removed, to make way for the bridge of -the Charing Cross Railway. As the Hungerford Suspension Bridge has -ceased to exist, an engraving has been given of it (Plate II. p. 59), in -order that some record of its appearance may remain. - - - - -CHAPTER III. - -_EARLY HISTORY OF THE GREAT WESTERN RAILWAY._ - -A.D. 1833--1835. AETATIS 27--30. - - SKETCH OF THE HISTORY OF RAILWAYS IN ENGLAND PRIOR TO 1833--THE - STOCKTON AND DARLINGTON--THE LIVERPOOL AND MANCHESTER--THE LONDON - AND BIRMINGHAM--PROPOSED RAILWAY BETWEEN LONDON AND BRISTOL--MR. - BRUNEL APPOINTED ENGINEER, MARCH 7, 1833--SURVEY OF THE - LINE--UNSUCCESSFUL APPLICATION TO PARLIAMENT IN 1834--SUCCESSFUL - APPLICATION IN 1835--REMINISCENCES OF MR. BRUNEL, - 1833-1835--EXTRACT FROM MR. BRUNEL'S DIARY, WRITTEN AT THE CLOSE OF - 1835. - - -Before entering upon the history of the Great Western and the other -railways of which Mr. Brunel was the engineer, it may be useful to give -a brief sketch of the development of the railway system, previous to the -period when he first became engaged in works of this description. - -The first railway in England designed for the conveyance of general -merchandise and passengers, was the Stockton and Darlington. An Act of -Parliament authorising the construction of this line was passed in 1821. - -In 1823, a further Act was obtained, in which a clause was inserted, at -the request of Mr. George Stephenson, then the engineer of the company, -taking power to work the railway by locomotive engines, and to employ -them for the haulage of passengers. This railway, which consisted of a -single line with four sidings in the mile, was opened for traffic on -September 27, 1825. Its success led at once to the promotion of similar -works in other parts of the country. - -Next in order must be noticed the celebrated railway between Liverpool -and Manchester. A project for constructing a line of railway between -these important towns was discussed as early as the year 1822; but a -company for carrying it out was not formed till two years later. In -1825, the directors applied to Parliament for an Act; and after a long -contest before a committee of the House of Commons, the preamble -approving of the construction of the railway was carried by a majority -of one. The Bill was, however, withdrawn, as the first two clauses -empowering the company to make the line, and to acquire land for that -purpose, were lost.[38] In the following year the Act was obtained, and -the works were commenced under the direction of Mr. George Stephenson. -The line was opened for traffic on September 15, 1830. - -In 1824, Mr. George Stephenson wrote a report on a proposed line -connecting Liverpool and Birmingham. Surveys were made, and plans -deposited; but the Bill was thrown out on standing orders. A similar -fate attended the introduction of a Bill in 1826. In 1830, a new line -was surveyed by Mr. Joseph Locke and Mr. Rastrick, under the direction -of Mr. George Stephenson. The Act was obtained in 1833, and the railway, -which was called the Grand Junction, and is now a part of the London and -North-Western system, was constructed by Mr. Locke.[39] - -In 1830, surveys were commenced by Mr. Robert Stephenson for a line -between London and Birmingham, and a Bill was introduced into Parliament -in 1832. The Liverpool and Manchester Railway had now been opened for -some time, and the promoters of the Birmingham line had the advantage of -being able to give in evidence the results of the working of the earlier -undertaking. Those results, it is said, were such as to startle most of -those who heard them. It was shown that a speed had been attained double -that of the fastest stage-coach, that the cost of travelling had been -diminished by one half, and that out of 700,000 persons carried since -the opening of the railway, only one had met with a fatal accident. The -amount of travelling between Liverpool and Manchester had increased -four-fold, and the value of the shares of the railway had risen one -hundred per cent. Similar evidence was given as to the results of the -working of the Stockton and Darlington Railway, and the promoters -endeavoured to prove that advantages at least as great would arise from -the construction of a railway between Birmingham and London. They were -successful in the House of Commons; but, they failed to convince the -Upper House that the benefits which such a railway would confer on the -country traversed by it were sufficient to entitle its promoters to -receive for it the sanction of the legislature. The Bill was again -introduced in the following session (1833); and, strange to relate, it -passed both Houses almost without opposition.[40] - - * * * * * - -Meanwhile, the principal merchants of Bristol, who had in 1825 made an -attempt to get up a railway company, were urged forward, both by the -inadequacy of their communications with the metropolis, and by the -success of the Liverpool and Manchester Railway, to make another effort. -In the autumn of 1832 a committee was formed of members of the -corporation, and other public bodies of the city of Bristol, to carry -out the project of a railway to London. - -The first step taken by the committee was the appointment of an engineer -to make the preliminary surveys, and to prepare an estimate of the cost -of the undertaking. - -Among the candidates for the post was Mr. Brunel. He was well known in -Bristol as the engineer of the Clifton Suspension Bridge, and of the -works for the improvement of the Floating Harbour. He had made many -friends among the leading citizens, and they used their best exertions -to procure his election; but there were several other candidates in the -field who had great local interest, and the contest was a close one. - -While the issue was yet undecided, an unexpected difficulty arose. Some -members of the committee resolved to select their engineer by means of a -competition among the candidates, as to which of them would provide the -lowest estimate. Upon this being announced, Mr. Brunel declared that he -must withdraw his name, as he could not consent to become a party to so -objectionable a proceeding. 'You are holding out,' he wrote to the -committee, 'a premium to the man who will make you the most flattering -promises. It is quite obvious that the man who has either least -reputation at stake, or who has most to gain by temporary success, and -least to lose by the consequences of disappointment, must be the winner -in such a race.' Happily, this plan was abandoned; Mr. Brunel obtained a -majority of votes, and was appointed engineer on March 7, 1833. - -He commenced the survey without delay; and in addition to his strictly -professional duties, he assisted in forming a committee in London, and -took a leading part in the consultations which were held upon various -important matters connected with the general interests of the -undertaking. - -A hasty survey of the country between London and Bristol occupied him -till the middle of June; and as soon as it was completed, and the course -of the line settled on, preparations were made for placing the scheme -before the public. - -The first public meeting was held on July 30, 1833. Mr. Brunel thus -refers to it in his diary:--'Got through it very tolerably, which I -consider great things. I hate public meetings: it is playing with a -tiger, and all you can hope is, that you may not get scratched, or -worse.' The result, however, seems to have been successful, and in a -month's time a company was formally constituted, and the parliamentary -survey commenced. - -Mr. Brunel organised a staff of assistants, at that time rather a -difficult task, and set them to work on various parts of the line. His -own duty of superintendence severely taxed his great powers of work. He -spent several weeks travelling from place to place by night, and riding -about the country by day, directing his assistants, and endeavouring, -very frequently without success, to conciliate the landowners on whose -property he proposed to trespass. - -His diary of this date shows that when he halted at an inn for the -night, but little time was spent in rest, and that often he sat up -writing letters and reports until it was almost time for his horse to -come round to take him on the day's work. 'Between ourselves,' he wrote -to Mr. Hammond, his assistant, 'it is harder work than I like. I am -rarely much under twenty hours a day at it.' - -A great portion of this labour was for the time thrown away, for as -November 30 drew near, it became evident that subscriptions were not -coming in to the extent which would enable the directors to lodge a Bill -for the whole line in the session of 1834. - -The directors therefore determined to apply to Parliament for powers to -make a railway from London to Reading, and from Bath to Bristol, 'as a -means of facilitating the ultimate establishment of a railway between -London and Bristol;' postponing till a future session their application -for an Act to enable them to complete the undertaking by making the line -from Reading to Bath. - -The Bill was introduced into the House of Commons, and on March 10, Lord -Granville Somerset moved that it be read a second time. This motion was -seconded by the Earl of Kerry, and supported by several influential -members, amongst whom were Mr. Labouchere (the late Lord Taunton) and -Mr. Daniel O'Connell. - -The second reading was carried by a majority of ninety in a House of 274 -members. - -The Bill was then referred to a committee which met on April 16, Lord -Granville Somerset being in the chair. Evidence was called to prove the -advantages of the railway to the agricultural and trading community of -the country through which it would pass, even if only the two proposed -divisions of the line were constructed. - -The traffic in merchandise between Bristol and London was at this time -principally carried on by means of water carriage, consisting, first of -the river Avon navigation from Bristol to Bath, next of the Kennet and -Avon Canal from Bath to Reading, and lastly of the river Thames from -Reading to London. The evidence went to show that the distance between -London and Reading, which by railway would be thirty-six miles, amounted -by the river to nearly eighty; that the delays and impediments arising -from drought, flood, and frosts on the rivers, were such as sometimes to -detain barges for several weeks; and that so great were the consequent -uncertainties and inconveniences of this navigation, that goods which -came as far as Reading by the canal, were frequently sent thence to -London by road, although at a great increase of expense. Even under the -most advantageous circumstances, goods could not be conveyed from -Reading to London in less than three days, or in less than a day by the -river Avon from Bath to Bristol. It was therefore contended, that to -form a railway which should supersede, or at all events come in aid of, -the worst portions of the navigation between London and Bristol, would -be an important public benefit.[41] The various advantages of the -measure were most fully discussed in an investigation which lasted -during fifty-seven days. Against the Bill was arrayed every class of -opponent that a private Bill could possibly encounter. Those interested -in the canals, rivers, and stage-coaches, opposed it from the fear of -competition; the inhabitants of Windsor opposed it, because the railway -did not run so near to the town as they wished; the corporation of -Maidenhead opposed it, because they thought that all the traffic which -paid toll on their bridge over the Thames would be diverted to the -railway; landowners and farmers near town opposed it, because they -feared it would bring produce to London from a distance, as cheap as -that supplied by themselves. - -There was another very formidable class of opponents to the Bill, -consisting of landed proprietors and owners of houses in the immediate -neighbourhood of London. - -Many engineers were called by these several opponents, to show that a -more advantageous line of railway might have been selected; but, upon -sifting the merits of the various new lines proposed, it became apparent -that the one chosen by Mr. Brunel was the best. Indeed, although some -trifling deviations of his line were suggested, the opposing engineers -admitted that in all essential features the railway had been most -skilfully laid out. It was generally agreed that the line through the -valley of the Thames, and thence in a direction north of the Marlborough -Downs, was the only proper course for a railway between Bristol and -London, as the levels were much better, and communication could be made -with much greater ease with the northern and South Wales districts, than -if the route to the south of the Marlborough Downs had been selected. - -The plans proposed for entering London raised great opposition. In this -respect public feeling has greatly changed, for now no railway is -thought complete which has not a terminus in the heart of London; and it -is considered an advantage for houses to be within easy reach of a -railway station; but in 1834 such a neighbour was looked upon with -horror and dismay--a nuisance to be, if possible, absolutely prohibited. - -When Mr. Brunel commenced the survey for the London terminus, he had -some idea of bringing the railway in on the south side of the Thames; -but this was abandoned, as it was found to involve very heavy works, and -the line proposed in the first Bill was made to terminate on the north -side of the river at Vauxhall Bridge. It was to have been carried on a -viaduct 24 feet high, with a parapet 6 feet 6 inches high, to prevent -the passengers looking into the windows of the neighbouring houses. - -The owners of the land through which this part of the line would pass -were influential members of the Upper House, and therefore the directors -thought it useless to brave their opposition; accordingly, on the -thirteenth day of the hearing, they abandoned the last two miles of the -viaduct, and proposed to stop at the 'Hoop and Toy,' a public-house -near the site of the South Kensington Station of the Metropolitan -Railway. - -But although the opposition of some of the landowners was conciliated by -this concession, that portion of the line through Brompton which had not -been abandoned was attacked with unabated energy. The residents in -Brompton opposed the Bill from the apprehension that the railway would -interfere with their quiet and seclusion; Brompton being at that time -considered, at any rate by one of the counsel for the opposition, 'the -most famous of any place in the neighbourhood of London for the -salubrity of its air, and calculated for retired residences.' They could -not, indeed, be blamed for indulging in these apprehensions, if they -really believed in their counsel's statement that 'streams of fire would -proceed from the locomotive engines.' - -Others objected to the viaduct itself as being an undertaking of so -colossal a nature as hardly to be practicable; and the supposed increase -of traffic and consequent obstruction in Piccadilly and other leading -thoroughfares brought down upon the promoters the opposition of the -Commissioners of Metropolitan Roads. - -All these objections were made the ground of much argument in committee, -and doubtless had great influence over the minds of those who voted -against the Bill. - -The engineering evidence occupied, as might be expected, the greater -part of the forty-two days during which witnesses were examined before -the committee, and of these forty-two days no less than eleven were -taken up by the cross-examination of Mr. Brunel. So protracted a -cross-examination has probably never been heard in any court or -committee-room. One of those present thus describes it:-- - -'The committee-room was crowded with landowners and others interested -in the success or defeat of the Bill, and eager to hear Brunel's -evidence. His knowledge of the country surveyed by him was marvellously -great, and the explanations he gave of his plans, and the answers he -returned to questions suggested by Dr. Lardner, showed a profound -acquaintance with the principles of mechanics. He was rapid in thought, -clear in his language, and never said too much, or lost his presence of -mind. I do not remember ever having enjoyed so great an intellectual -treat as that of listening to Brunel's examination, and I was told at -the time that George Stephenson and many others were much struck by the -ability and knowledge shown by him.' - -In his evidence, Mr. George Stephenson stated that he did not know any -existing line so good as that proposed by Mr. Brunel. 'I can imagine (he -said) a better line, but I do not know of one so good.'[42] - -At length, on the fifty-fourth day of the sittings of the committee, Mr. -Harrison, K.C., rose to reply on behalf of the promoters, and on the -conclusion of his address the Bill was passed. - -In the House of Lords the second reading was moved by Lord Wharncliffe. -It was opposed, and on a division being taken, the motion was lost by a -majority of seventeen (30 content and 47 non-content). The Bill was -therefore thrown out. - -The directors, undaunted by their defeat, lost no time in making -preparations for bringing a Bill before Parliament in the session of -1835, with such improvements as the experience of the past campaign -suggested to them. Taking into consideration the various grounds on -which opposition had been raised to the plans they had proposed for -entering London through the Brompton district, they opened negotiations -with the London and Birmingham Railway Company, and arrangements were -concluded by which the traffic of the Great Western Railway was to be -carried upon the London and Birmingham line for the first four miles out -of London, the junction being made a little to the west of the Kensal -Green Cemetery. - -They had also during the autumn raised money enough to enable them to -apply to Parliament for powers to construct the whole of the line from -London to Bristol. They thus escaped all the sarcastic observations -which had been made upon the scheme of 1834, of which it had been said, -that it would be a head and a tail without a body, and neither 'Great' -nor 'Western,' nor even a 'railway' at all, but 'a gross deception, a -trick, and a fraud upon the public, in name, in title, and in -substance!' - -On March 9, the earliest day allowed by the standing orders, the Bill -was read a second time and committed. A division being taken on the -motion for committal, there appeared in favour of the motion 160, and -against it none but the tellers. - -Shortly after its first meeting, the committee, of which Mr. Charles -Russell, then member for Reading, was chairman, came to the resolution -that, inasmuch as the evidence given in the previous year as to the -public advantages of a Bristol railway had been referred to them by -order of the House, they needed no further evidence on that subject. -Counsel were therefore directed to confine their case as much as -possible to the merits of the line proposed. - -Evidence was called by the opponents chiefly with a view to show the -advantages of a proposed line from Basing to Bath, and the inexpediency -of granting an entirely new line of 115 miles in length to the Great -Western Railway Company, which involved the construction of a 'monstrous -and extraordinary,' 'most dangerous and impracticable, tunnel' at Box, -and this, when 44 miles of railway in a western direction--viz. as far -as Basingstoke, had already been sanctioned by the legislature in the -Southampton Railway Act, passed in the previous session. The promoters -of the Bill contended that the levels of the Basing and Bath line were -not so good as those proposed for their own, and that the Great Western -Railway would approach almost every town of importance situated on the -proposed Basing and Bath line, by means of short branches; whilst at the -same time it presented the great advantage of being capable of easy -extension to Gloucester and Wales, and to Oxford, an object wholly -unattainable by the other line. In reply to these assertions, the -opponents maintained that although the levels of the Basing and Bath -Railway presented greater inclinations than those of the Great Western, -yet that they were so balanced as that the rises and falls compensated -one for another, so as to render the line practically level. The -enunciation of this theory called forth a remark by the chairman that -according to this principle the Highlands of Scotland would be as good -as any other place for the construction of a railway. - -The preamble was voted proved, and the Bill passed the House of Commons -without further opposition, and on May 27 was read a first time in the -Lords. On June 10, the second reading was carried after a sharp debate, -the numbers being 46 contents, and 34 non-contents. - -Lord Wharncliffe was chairman of the committee.[43] The proceedings -began by an opposition on the standing orders, which, after much -skirmishing, were voted to have been complied with. The promoters, -however, judged from the nature of the first day's proceedings, that -they had to expect a contest of no inconsiderable duration; and the -result proved their anticipations to have been correct. For forty days -the battle was fought with a degree of earnestness and vigour on both -sides, almost unequalled in any similar proceedings. - -The committee soon came to the same decision as the House of Commons, -that, with regard to the advisability of a Bristol railway, they were -satisfied, and needed no further evidence. The case became then one of -mere comparison between the relative merits of the two lines proposed. - -The case in support of the Bill occupied eighteen days, and was closed -with a speech by the Hon. John Talbot. - -Mr. Serjeant Merewether, whom the opponents had chosen as their leader -in the House of Lords, was then heard on their behalf, and occupied no -less than four days in the delivery of his speech, in which certainly no -argument that ingenuity could devise was omitted to strengthen his case. -There was hardly any conceivable injury which, according to the learned -serjeant's notions, the Great Western Railway would not inflict. It was -said that the Thames would be choked up for want of traffic, the -drainage of the country destroyed, and Windsor Castle left unsupplied -with water. As for Eton College it would be absolutely and entirely -ruined: London would pour forth the most abandoned of its inhabitants to -come down by the railway and pollute the minds of the scholars, whilst -the boys themselves would take advantage of the short interval of their -play hours to run up to town, mix in all the dissipation of London life, -and return before their absence could be discovered. Moreover, while the -beauty of the country and the retirement of private dwellings would be -destroyed, the interests of the public would be far more effectually -served by the adoption of the Basing and Bath line, and a line from the -London and Birmingham Railway to Gloucester. This was in fact the point -at issue, and on this the result of the contest depended. The promoters -of the Bill had called, in support of their line, in addition to Mr. -Brunel, who being engineer to the company might be considered an -interested witness, Mr. Locke, Mr. Palmer, Mr. Price, Mr. George -Stephenson, and Mr. Vignoles. They expressed their unqualified -approbation of the line chosen by Mr. Brunel, and of the estimates he -had prepared. - -The preamble was proved, and after an unsuccessful opposition the Bill -was read a third time, on August 27. The Royal Assent was given on the -last day of that month.[44] - - * * * * * - -During this contest Mr. Brunel made among his fellow-labourers many deep -and lasting friendships. One of the most intimate of these friends, Mr. -St. George Burke, Q.C., has, in compliance with a request made to him, -furnished the following reminiscences of his intercourse with Mr. -Brunel during the progress of the Bill through Parliament. - - - March 9, 1869. - - 'My dear Isambard,--You wish me to supply you with reminiscences of - my old associations with your father, in order that, in your - biography of him, you may present a true picture of those features - of his character which so endeared him to his most intimate - friends. - - 'For many years it was my good fortune to enjoy his friendship, and - many of the pleasantest hours of my life were due to it. - - 'For a period of nearly three years, viz. during the contest for - the Great Western Railway Bill, I think that seldom a day passed - without our meeting, whether for purposes of business or pleasure, - both of which his buoyant spirits enabled him to combine in a - manner which I have seldom seen equalled. - - 'It would be wearisome to detail the many incidents which occurred - illustrative of the singularly facile manner in which, in the midst - of the heaviest and most responsible labours, he could enter into - the most boyish pranks and fun, without in the least distracting - his attention from the matter of business in which he was engaged; - but all who knew him as I did could bear testimony to this - characteristic of his disposition. - - 'I believe that a more joyous nature, combined with the highest - intellectual faculties, was never created, and I love to think of - him in the character of the ever gay and kind-hearted friend of my - early years, rather than in the more serious professional aspect - under which your pages will, no doubt, rightly depict him. - - 'In 1833 your father and I occupied chambers facing each other in - Parliament Street, and as my duties involved the superintendence, - as Parliamentary agent, of the compliance with all the Standing - Orders of Parliament, and very frequent interviews and negotiations - with the landowners on the line, we were of necessity constantly - thrown together. To facilitate our intercourse, it occurred to your - father to carry a string across Parliament Street, from his - chambers to mine, to be there connected with a bell, by which he - could either call me to the window to receive his telegraphic - signals, or, more frequently, to wake me up in the morning when we - had occasion to go into the country together, which, it is needless - to observe, was of frequent occurrence; and great was the - astonishment of the neighbours at this device, the object of which - they were unable to comprehend. - - 'I believe that at that time he scarcely ever went to bed, though I - never remember to have seen him tired or out of spirits. He was a - very constant smoker, and would take his nap in an arm-chair, very - frequently with a cigar in his mouth; and if we were to start out - of town at five or six o'clock in the morning, it was his frequent - practice to rouse me out of bed about three, by means of the bell, - when I would invariably find him up and dressed, and in great glee - at the fun of having curtailed my slumbers by two or three hours - more than necessary. - - 'No one would have supposed that during the night he had been - poring over plans and estimates, and engrossed in serious labours, - which to most men would have proved destructive of their energies - during the following day; but I never saw him otherwise than full - of gaiety, and apparently as ready for work as though he had been - sleeping through the night. - - 'In those days we had not the advantage of railways, and were - obliged to adopt the slower, though perhaps not less agreeable, - mode of travelling with post-horses. Your father had a britzska, - so arranged as to carry his plans and engineering instruments, - besides some creature comforts, never forgetting the inevitable - cigar-case among them; and we would start by daybreak, or sometimes - earlier, on our country excursions, which still live in my - remembrance as some of the pleasantest I have ever enjoyed; though - I think I may safely say that, pleasurable as they were, we never - lost sight of the business in which we were engaged, and for which - our excursions were undertaken. - - 'I have never known a man who, possessing courage which to many - would appear almost like rashness, was less disposed to trust to - chance or to throw away any opportunity of attaining his object - than was your father. I doubt not that this quality will be fully - exemplified in the details which you will have received of his - engineering experiments; but I speak of him also in the character - of a diplomatist, in which he was as wary and cautious as any man I - ever knew. - - 'We canvassed many landowners together, and I had plenty of - opportunities of judging of his skill and caution in our - discussions with them, though we had many a good laugh afterwards - at the arguments which had been addressed to us as to the inutility - and impolicy of the scheme in which we were engaged, and the utter - ruin it would be sure to entail on its promoters, as well as on the - country affected by it. - - 'I frequently accompanied him to the west of England, and into - Gloucestershire and South Wales, when public meetings were held in - support of the measures in which he was engaged, and I had occasion - to observe the enormous popularity which he everywhere enjoyed. The - moment he rose to address a meeting he was received with loud - cheers, and he never failed to elicit applause at the end of his - address, which was distinguished as much by simplicity of language - and modesty of pretension as by accurate knowledge of his subject. - - Yours very truly, - - ST. GEORGE BURKE. - - Isambard Brunel, Esq.' - -The following is an extract from Mr. Brunel's diary, written at the end -of the year 1835:-- - - - 53 Parliament Street, December 26. - - What a blank in my journal [_the last entry is dated January - 1834_], and during the most eventful part of my life. When last I - wrote in this book I was just emerging from obscurity. I had been - toiling most unprofitably at numerous things, unprofitably, at - least, at the moment. The railway was certainly being thought of, - but still very uncertain. What a change. The railway now is in - progress. I am thus engineer to the finest work in England. A - handsome salary, on excellent terms with my directors, and all - going smoothly. But what a fight we have had, and how near defeat, - and what a ruinous defeat it would have been. It is like looking - back upon a fearful pass; but we have succeeded. - - And it is not this alone, but everything I have been engaged in has - been successful. Clifton bridge--my first child, my darling, is - actually going on: recommenced work last Monday--glorious!! [_Here - follows a list of the undertakings on which he was then engaged._] - I think this forms a pretty list of real sound professional work, - unsought for on my part, that is, given to me fairly by the - respective parties--all, except the Wear Docks, resulting from the - Clifton bridge, which I fought hard for, and gained only by - persevering struggles.... And this at the age of twenty-nine. I - really can hardly believe it, when I think of it. I am just leaving - 53 Parliament Street, where I may say I have made my fortune, or, - rather, the foundation of it, and I have taken 18 Duke Street. - - - - -CHAPTER IV. - -_RAILWAY WORKS._ - -A.D. 1835--1859. AETATIS 30--54. - - CONSTRUCTION OF THE GREAT WESTERN RAILWAY--THE BOX TUNNEL--THE BATH - AND BRISTOL STATIONS--THE PADDINGTON STATION--THE GREAT WESTERN - HOTEL--BRANCHES AND EXTENSIONS OF THE GREAT WESTERN RAILWAY--THE - BRISTOL AND EXETER RAILWAY--RAILWAYS IN DEVONSHIRE AND - CORNWALL--RAILWAYS TO BASINGSTOKE, TO WEYMOUTH, AND TO - SALISBURY--IN SOUTH WALES--IN IRELAND--IN ITALY--IN - INDIA--SUPERVISION OF WORKS--MR. BRUNEL'S ENGINEERING STAFF--HIS - REPUTATION AS A WITNESS--REMINISCENCES OF MR. BRUNEL, 1835-1838. - - -In the extract from Mr. Brunel's diary given at the close of the last -chapter he refers to the successful issue of the contest for the Great -Western Railway Act as a very important event in his life. - -As the result proved, he did not take too hopeful a view of his future -prospects; for from that time to his death he was fully employed as the -engineer of railways which, in number and importance, were not inferior -to those of any of his contemporaries. Of the main lines he constructed, -one extends uninterruptedly from London to the Land's End, and another -to the extremity of South Wales, at Milford Haven, 285 miles from -Paddington. - - * * * * * - -It would be impossible to describe in detail all the engineering works -which are to be found on Mr. Brunel's railways, the aggregate length of -which is upwards of 1,200 miles; but in this chapter it is proposed to -give a brief sketch of the lines he constructed, omitting all that can -be more properly inserted in the three chapters which follow, relating -to the broad gauge, to the Atmospheric System, and to the bridges and -viaducts. - - * * * * * - -The Great Western Railway was opened to Maidenhead, a distance of nearly -twenty-three miles, in June 1838, and to Twyford, eight miles farther -on, in July 1839. A description of the Wharncliffe Viaduct at Hanwell -will be found at p. 172, and of the Maidenhead bridge at p. 173. - -The line from Twyford to Reading was opened in March 1840, and from -Reading to Chippenham by May 1841. Meanwhile the portion from Bristol to -Bath had been opened in August 1840. The last division, namely, that -from Chippenham to Bath, containing the Box Tunnel, was opened on June -30, 1841; and the railway was completed throughout its whole length. - - * * * * * - -A considerable part of the history of the Great Western Railway is -connected with the adoption on it of the broad, or 7-foot gauge, and -will be dealt with in the next chapter, in which is also given some -account of the longitudinal system of permanent way. - -The bridges are described in Chapter VII.; but some of the other works -may be noticed here. - -In laying out the line, Mr. Brunel endeavoured to make it as straight -and as level as possible throughout, and to concentrate those changes of -level, which could not be avoided, into short inclines, to be worked, if -necessary, by auxiliary power. - -Accordingly the line is thus divided:-- - - Miles Yards - - Level, or with an inclination not exceeding - 4 feet in the mile 67 88 - - Above 4 feet, and not exceeding 8 feet in - the mile 47 110 - - Steep inclines 3 1210 - -The steep inclines are two in number, of a gradient of 1 in 100, or -about 53 feet in a mile, and descend towards the Bristol end of the -line. - -The Wootton Basset incline, 85-1/2 miles from London, is 1 mile 550 yards -long. - -The second incline is at Box, 99 miles from London, and is 2 miles 660 -yards in length. An assistant engine is still occasionally used to work -heavy trains at this point. - -On this incline the line passes through the Box Tunnel. This tunnel is -the first out of London, and could only have been dispensed with by -taking a circuitous route several miles longer than that adopted by Mr. -Brunel. - -The tunnel is 1-7/8 mile in length, and is ventilated by six shafts. -They are 30 feet in diameter, and from 70 to 300 feet deep. - -The Box Tunnel had been the subject of much criticism before the works -were commenced; and during its actual construction it did not escape the -unfavourable notice of those who were ignorant of the difficulties which -presented themselves, and the means which had been taken to overcome -them. Indeed, for some time after the opening of the line, there were -travellers who used to avoid the terrors of the tunnel by posting along -the turnpike road in that part of their journey. - -Mr. Brunel never troubled himself about the ordinary gossip which is -always circulated concerning any remarkable work; but matters assumed a -different aspect when, a year after the completion of the tunnel, doubts -were expressed as to its safety by an eminent geologist, at a meeting of -the Institution of Civil Engineers. Mr. Brunel, who was on terms of -friendly intercourse with the speaker, addressed to him the following -letter:-- - - - June 21, 1842. - - I assure you, my dear Sir, that when my attention had been drawn to - the statements reported to have been made by you on this subject, - I refrained as far as possible from expressing any opinion. I - thought it my duty to read the notes taken, but I never said that I - thought your statements were correct. Indeed, I had hoped to have - avoided the necessity of making any observations upon these - statements; but as a letter to Mr. Saunders on such a subject is - almost the same thing as if it were addressed to myself, and as it - was shown to me, it would not be candid towards you if I now - refrained from saying, that the opinions you are reported to have - expressed with respect to the Box Tunnel are by no means considered - correct, either by myself or by those others who, from being - intimately acquainted with the rock as it was really found, and the - works as they were really executed, are capable of judging. - - In the notes shown to me the observations alluding to this work in - particular, as an illustration of the views you were explaining, - appear to have been curtailed, and the allusions rendered somewhat - less direct; but still the inference unavoidably to be drawn from - them is, that the back joints, as we call them, and other defects - which exist originally, or which show themselves after a time, in - this rock, are not well known, and tolerably well understood and - guarded against, by practical engineers, and even by our workmen. - In this opinion I assure you you are mistaken. Ignorant as I may - probably be myself of the science of geology, I cannot have been - engaged for several years in making very extensive excavations, - probably the largest hitherto made, in this particular rock, having - also the opportunity of examining very old and large quarries in - the same rock and close to the line, having among my assistants men - not meanly acquainted with this particular branch of geology, and - surrounded by workmen of considerable experience, I cannot have - gone through such a study without acquiring a very intimate and - practical knowledge of the structure and peculiarities of the - particular mass of rock which is now in question; and I will say - frankly what I feel upon this point, which is, that I ought now to - possess a more thorough and practical knowledge of this particular - rock and its defects, and the best mode of remedying them, than - even you yourself, with your immeasurably greater scientific - knowledge of rocks generally. - - The opinion you are said to have expressed of there being great - danger of some serious accident occurring in the tunnel is, I am - firmly convinced, erroneous; at all events the reason given - convinces me that you have not become acquainted with the means - which have been taken by me to examine and to ascertain the - security of every part of the rock, to remove or to support with - masonry any part not so ascertained to be secure, or with the - precautions taken to prevent any such accidents as those you have - imagined. And notwithstanding the heavy responsibility which rests - upon me, from all which you gentlemen of science are, happily for - yourselves, so free, I feel that as regards the works of the Box - Tunnel everything necessary has been done to render them secure, - and that the doubts and fears you have so easily raised, but which - it might be more difficult again to set at rest, are entirely - unfounded. - - In conclusion, I must observe that no man can be more sensible than - I am of the great advantage it would be to me as a civil engineer - to be better acquainted with geology, as well as with many other - branches of science, that I have endeavoured to inform myself on - the subject, and that I have not altogether thrown away the many - opportunities afforded me in my professional pursuits; but that if - from a conviction that you possessed information far more extensive - than mine, if from doubts of the sufficiency of my abilities or the - means I was likely to bring to bear upon the subject, if from a - fear of such consequences as you now anticipate, you had kindly, on - any one of the many occasions when I have had the pleasure of - meeting you, intimated that you had any suggestions to make to me, - I should have been anxious to have availed myself of your - assistance. But after the lapse of years, the first intimation I - have of such doubts is the very public expression of a very strong - opinion, which, if weight be attached to it, must tend to alarm the - public unnecessarily, and to injure the value of the property of - individuals who have embarked several millions in that property. - -Between Chippenham and Bristol the nature of the building stone enabled -Mr. Brunel, at moderate cost, to make the bridges, tunnel fronts, and -stations ornamental features in the picturesque scenery through which -the railway passes. - -He took great pleasure in finishing minutely the various designs, and -making them correct in their proportions and details. One tunnel front, -near Bristol, may be singled out for especial mention. During its -construction a part of the ground behind slipped away, and it became -unnecessary to complete the top of one of the side walls. It was -therefore left unfinished, and was planted with ivy so as to present the -appearance of a ruined gateway. - -The roofs of the Bath and Bristol stations are of large span, and are -handsome architectural structures. They are each in the form of a Tudor -arch; the Bristol roof is 72 feet span, and the Bath roof 50 feet span. -The framing is an example of a peculiar form of construction, somewhat -analogous to that adopted in the large shipbuilding sheds in the -dockyards. There are no cross tie-rods, but each principal of the roof -is formed of two frameworks, like cranes, meeting in the middle of the -roof; the weight being carried on columns near the edge of the platform, -and the tail ends of the frames held down by the side walls. As the two -frames do not press against each other at their meeting point at the -ridge of the roof, there is no outward thrust. The side walls being on a -viaduct could not without difficulty have been made to resist a -horizontal thrust. - -At the Bristol station Mr. Brunel introduced hydraulic machinery for -working lifts. By these the waggons were lowered to and raised up from -the goods shed, which was placed at the level of the ground, about 12 -feet below the railway. - -Although the works already described were completed in 1841, the -permanent terminus at Paddington was not commenced till the year 1849. -It was completed in 1854. Previously to that time a temporary station -had been used, the booking offices being under the arches of the -Bishop's Road bridge. - -As the level of the railway was lower than that of the surrounding land, -no exterior architectural effect could be produced; but Mr. Brunel took -this opportunity to carry out his views as to the proper structural use -of metal in works of this description. - -In the design of the ornamental details, he obtained the assistance of -Mr. (now Sir Matthew) Digby Wyatt. - -The interior of the principal part of the station is 700 feet long and -238 feet wide, divided in its width by two rows of columns into three -spans of 68, 102, and 68 feet, and is crossed at two points by transepts -50 feet wide, which give space for large traversing frames. The roof is -very light, consisting of wrought-iron arched ribs, covered partly with -corrugated iron and partly with the Paxton glass roofing, which Mr. -Brunel here adopted to a considerable extent. The columns which carry -the roof are very strongly bolted down to large masses of concrete, to -enable them to resist sideways pressure. - -This station may be considered to hold its own in comparison with the -gigantic structures which have since been built, as well as with older -stations. The appearance of size it presents is due far more to the -proportions of the design than to actual largeness of dimension. The -spans of the roof give a very convenient subdivision for a large -terminal station, dispensing with numerous supporting columns and at the -same time avoiding heavy and expensive trusses. The graceful forms of -the Paddington station, the absence of incongruous ornament and useless -buildings, may be appealed to as a striking instance of Mr. Brunel's -taste in architecture and of his practice of combining beauty of design -with economy of construction. - -The goods station was erected at about the same time as the passenger -station, and is remarkable for the completeness of its arrangements, and -for the great use made of hydraulic machinery. This is also applied in -the passenger station.[45] - -In connection with the Paddington station mention may be made of the -Great Western Hotel, which was built at the extremity of the land -belonging to the railway company. - -When, in 1854, no tenant could be found for it, a few of the -shareholders of the Great Western Railway, being unwilling that the -building should remain empty and be a loss to the proprietors, formed -themselves into a company to lease and work the hotel. Mr. Brunel became -a Director, and shortly afterwards (in December 1855) the chairman. He -occupied this post till his death, by which time the hotel had become -very prosperous. He found attendance at the meetings of the Directors -and the supervision of the management of the hotel a very agreeable -relaxation from the more important duties which took him to Paddington. - - * * * * * - -The branches and extensions of the Great Western Railway, as far as -their history affected the general interests of the company, are -referred to in the chapter on the broad gauge. Branches were opened to -Oxford in 1844, to Windsor in 1849, to Wycombe in 1854, to Uxbridge in -1856, to Henley in 1857, and to Brentford in July 1859. - - * * * * * - -The Bristol and Exeter Railway is a continuation of the Great Western -Railway, and was opened to Exeter in 1844. The two portions of it, from -Bristol to Taunton, and from Taunton to Exeter, are in marked contrast -to each other. The former part of the line is almost level, and has very -easy curves. Between Taunton and Exeter it passes over the high ground -on the borders of Devonshire, with the Whiteball Tunnel at the summit, -5/8 mile in length. On this part of the line there are long gradients of -from 1 in 80 to 1 in 120. Mr. Brunel resigned the position of engineer -in 1846, in consequence of differences having arisen between the Bristol -and Exeter and the Great Western Companies, which, in Mr. Brunel's -opinion, made it impossible for him to continue engineer to both -railways. - -The South Devon Railway, and the adoption on it of the Atmospheric -System, are described in Chapter VI. In connection with this line is the -important Torquay branch, and the railway in continuation of it to -Dartmouth. This was completed as far as Paignton during Mr. Brunel's -lifetime. - -The South Devon and Tavistock Railway branches off from the South Devon -Railway near Plymouth, and has several large viaducts. - -On the Cornwall Railway from Plymouth to Truro, and the West Cornwall -Railway from Truro to Penzance, the most remarkable works are the -viaducts, and the Royal Albert Bridge. - -In the case of the Cornwall Railway, it became necessary to reduce the -capital expenditure, even at the cost of increasing the charges for -maintenance. With this object the line was re-examined and modifications -introduced, principally by an increase in the extent of viaduct. These -lines pass through a very difficult country; involving the adoption of -steep gradients and sharp curves. Mr. Brunel, in a memorandum written in -1845, after having explained his reasons for considering that the -prejudicial effects of gradients and curves were commonly overrated, -gives the following opinion in reference to the proposed Cornwall -Railway:-- - - I must not be understood to argue against the advantage of straight - lines or large and easy curves, but I wish to show that where small - curves are unavoidable, they can in practice be so constructed as - not to be very prejudicial; and I consider that the character of - the country in Cornwall is such that no railway can be constructed - at any moderate expense without either sacrificing all - consideration for the interests of localities and the position of - the population to the mere choice of levels, or without steep - gradients and sharp curves. - -The principal lines branching off from the Great Western, and since -incorporated with it, are, on the south, the Berks and Hants, from -Reading to Basingstoke and Hungerford; and the Wilts and Somerset, to -Weymouth and Salisbury. On the north-west is the Cheltenham and Great -Western Union Railway, from Swindon to Cheltenham and Gloucester. This -line passes through the Cotswold Hills at Sapperton by a tunnel 1-3/8 -mile in length. The Gloucester and Dean Forest Railway runs from -Gloucester to Grange Court, and thence to Ross and Hereford. - -The South Wales Railway, which extends from Grange Court to Milford -Haven, contains a tunnel at Swansea 1/3 mile long, and some of Mr. -Brunel's most important works, including the Chepstow bridge and several -other bridges of considerable size, and the viaducts at Landore and -Newport. There are also on this line four opening bridges across -navigable channels. The works at the termination of the line at Neyland, -in Milford Haven, are described in Chapter XIV. Mr. Brunel considered -that Milford Haven, with its excellent harbour, which can be entered at -all times of tide by the largest vessels, would probably become a great -port for ocean steamers, and especially for the 'Great Eastern' and -ships of her class. - -There are also in South Wales the following railways: the Taff Vale, the -Vale of Neath, the Llynvi Valley, and the South Wales Mineral. The Taff -Vale, a line from Cardiff to Merthyr, was opened on the narrow gauge in -1841.[46] On this railway is the lofty masonry viaduct at Quaker's Yard. - -On the Vale of Neath Railway, from Neath to Aberdare and Merthyr, there -is a tunnel, near Merthyr, 1-1/4 mile long, and 650 feet below the summit -of the hill. - -Full advantage is taken on this railway of the facilities which the -broad gauge offers for heavy traffic. The line has long steep gradients, -and the locomotives used on it, of the class known as tank engines, are -of great power. One of these gradients is 4-1/2 miles long, with an -inclination of 1 in 50. Large quantities of coal are brought down by -this railway to the Swansea and Briton Ferry Docks. The coal of South -Wales is of a friable nature, and, in order to avoid the breakage -consequent on the ordinary mode of shipping coal, by tipping it down a -shoot, Mr. Brunel introduced on a large scale the use of trucks carrying -four iron boxes, each box about 4 feet 8 inches cube, and containing two -and a half tons of coal. At the docks machinery is provided by which -each box is lowered down into the hold of the ship, and the under side -being allowed to open, the coal is deposited at once on the bottom of -the vessel. - -The Llynvi Valley Railway is a short line, leading from the South Wales -Railway at Bridgend into the coal and iron districts. - -The South Wales Mineral Railway is another line of the same class. It -passes through a very heavy country, and has on it a self-acting incline -of 1 in 9, 3/4 mile long, worked by a rope, and a tunnel 5/8 mile long, -and 470 feet below the surface. - -In connection with the South Wales district is the Bristol and South -Wales Union Railway, a line running from Bristol to the banks of the -Severn, across which the traffic is carried by a steamer to a short -branch from the South Wales Railway on the other side. This railway had -been for a long time contemplated, and Mr. Brunel devoted much time to a -careful investigation of the Severn in order to determine the most -suitable point for the crossing. He decided that the best place would be -at what is known as the New Passage. The arrangements had to be made in -accordance with the requirements of the Admiralty. Trains run to the end -of timber piers extending into deep water, and there are staircases and -lifts leading to pontoons, alongside which a steamer can come at all -times of tide. The tide at this part of the Severn rises 46 feet. - -The three railways last mentioned were not completed during Mr. Brunel's -lifetime. - - * * * * * - -The Bristol and Gloucester Railway, on which is the tunnel at Wickwar, -3/4 mile long, was opened in 1844, and passed into the hands of the -Midland Company in 1846. - - * * * * * - -The northern extensions of the Great Western Railway are the Oxford and -Rugby, constructed as far as Fenny Compton; the Birmingham and Oxford -Junction; and the Oxford, Worcester, and Wolverhampton Railways. - -Mr. Brunel ceased to be engineer of the last-mentioned company in 1851, -and the works were completed by Mr. Fowler. The Oxford, Worcester, and -Wolverhampton line has since, under the title of the West Midland, -become a part of the Great Western Railway. - - * * * * * - -In Ireland Mr. Brunel was engineer of the line from Dublin to Wicklow, -round Bray Head, and of a line from Cork to Youghal. - - * * * * * - -He laid out two railways in Italy, the line from Florence to Pistoja, -and that across the Apennines from Genoa to Novi and Alessandria, in the -direction of Turin and Milan. He acted as engineer during the -construction of the former line; but the works of the latter were -carried out by the Sardinian Government. - - * * * * * - -One of the last of Mr. Brunel's important railways was the Eastern -Bengal Railway, a line of about 100 miles in length, in a north-easterly -direction from Calcutta. He took a great interest in the work and -devoted much time to the special arrangements and designs, and to the -best way of crossing the Ganges and its branches in the future extension -of the railway; but no part of it was opened during his lifetime. - - * * * * * - -It was impossible for Mr. Brunel to look after all his works to the same -extent as he had done in the case of the Great Western Railway; and he -was compelled to spend a very considerable amount of time in attendance -on Committees of the Houses of Parliament on behalf of the railways to -which he was engineer. Mr. Brunel frequently regretted this, and -considered it a great evil that engineers were prevented by their duties -during the session from attending properly to the construction of their -works. He endeavoured as far as possible to superintend the execution of -his different undertakings. He availed himself of every opportunity of -examining them, and was acquainted throughout with all the designs which -were prepared. He would take advantage of two or three free days to go -down to the distant works in South Wales or in Cornwall, looking after -details, such as the pickling tanks for timber, and the masonry of the -viaducts. - -He was fortunate in the selection of the members of his staff, and in -his organisation of it. He had a rare power of utilising the -capabilities of his different assistants; and although he had to deal -with a great variety of men, he managed that they should work in harmony -with him. From the complete personal supervision Mr. Brunel sought to -maintain over all his works, his assistants had not perhaps so many -opportunities of independent action as they might otherwise have -obtained, but they had, on the other hand, the advantage of constant -personal communication with their chief. - -After the time when Mr. Brunel's works became so numerous, and his time -so much occupied, that he could not exercise in person that general -supervision which he conceived to be necessary, he was ably assisted by -Mr. Robert Pearson Brereton, who, on the death of Mr. Hammond in 1847, -became the chief of his engineering staff. - -Mr. Brunel rarely made any changes in the _personnel_ of his office. Mr. -Brereton had become one of his assistants in 1836; and his secretary, -the late Mr. Joseph Bennett, came to him in the same year. - - * * * * * - -The Great Western Railway retained its early place in his affections, -and among his most valued friends were members of the Board of -Directors, Mr. Saunders the Secretary, and other officers of the -company. When in the last year of his life he was obliged to go to Egypt -for his health, it was a matter of deep anxiety to him lest his absence -from England should cause any alteration in his relations with the -Company, and it was a source of great pleasure to him that no such -consequences followed. - - * * * * * - -Mr. Brunel's position as confidential adviser of so large a number of -railway companies gave him frequent opportunities of acting as mediator -between contending parties; and his decisions were always received with -respect, for he was known to be scrupulously just. - -Besides the more friendly task of reconciling opponents he had a large -practice as a referee under Acts of Parliament and orders of the -superior courts; and displayed in these matters great judicial -abilities. - -In all the causes and parliamentary contests affecting the various -companies of which he was engineer, Mr. Brunel was a very important -member of the preliminary consultations, and during the proceedings -counsel relied with confidence on his suggestions. - - * * * * * - -One of the most arduous parts of his duty, as engineer of the Great -Western Railway Company, was connected with the conduct of the great -cases of Ranger and MacIntosh. To the former of these reference is made -in the letter printed below, at p. 478. The MacIntosh case, which was -commenced shortly after the opening of the line, was not concluded -before Mr. Brunel's death. He was compelled to devote a considerable -portion of his time to it, even after his return home in the evening, -during the launch of the 'Great Eastern.' - - * * * * * - -Mr. Brunel had a very high reputation as a witness. Mr. St. George -Burke, Q.C., has communicated a memorandum on this subject. - - 'As a witness he could always be relied on as a perfect master of - the case he had to support, and he had the rare quality of - confining his answers to a simple reply to the questions put to - him, without appearing as an advocate. He was, however, extremely - particular as to the questions which should be put to him in his - examination in chief, and was therefore never satisfied to entrust - the preparation of his proof to the solicitor, without revising it - himself. - - 'In his cross-examinations he was generally a match for the most - skilful counsel, and by the adroitness of his answers would often - do as much to advance his case as by his examination in chief. - - 'He was almost as much of a diplomatist as an engineer, and knew - perfectly well how to handle a case in the witness-box so as to - leave no loophole for his opponents to take advantage of. At the - same time he was a perfectly honest witness, and while he avoided - saying more than was necessary for the advancement of the cause in - which he was engaged, he would have scorned to say or imply - anything by his evidence inconsistent with strict truth. - - 'Although he had attained to great celebrity as a witness, the - committee room being crowded to hear him, he always declined to - engage in the very lucrative work of a professional witness. He - made a rule never to appear except on behalf of undertakings of - which he was the engineer, or with which his own companies were - interested. To help a friend, he occasionally but very rarely broke - through this resolve; but, whether he appeared in support of his - own plans or those of others, there were few, if any, professional - men whose evidence carried more weight than his did before - Parliamentary Committees.' - -The following memorandum from Mr. George T. Clark, of Dowlais, formerly -one of Mr. Brunel's assistants, contains his recollections of Mr. Brunel -during the construction of the Great Western Railway:-- - - 'I made your father's acquaintance, rather characteristically, in - an unfinished tunnel of the Coal-pit Heath Railway; and when the - shaft in which we were suspended cracked and seemed about to give - way, I well remember the coolness with which he insisted upon - completing the observations he came to make. Shortly afterwards I - became, at his request, his assistant; and during the - parliamentary struggle of 1835, and the subsequent organisation of - the staff, and commencement of the works of the Great Western, I - saw him for many hours daily, both in his office and in the field, - travelled much with him, and joined him in the very moderate - recreation he allowed himself. - - 'These two years, and the preceding year, 1834, were, I apprehend, - the turning points of his life. His vigour, both of body and mind, - were in their perfection. His powers were continually called forth - by the obstacles he had to overcome; and the result of his - examinations in the committee rooms placed him, in the opinion of - the members of the legislature, and of his own profession, in the - very first rank of that profession, both for talents and knowledge. - - 'I wish I could convey to you even a tolerable idea of your father - as he was in those years, during which I knew him intimately, and - saw him often under circumstances of great difficulty. - - 'He was then a young man, but in the school of the Thames Tunnel he - had acquired a close acquaintance with all kinds of masons' and - carpenters' work, the strength and cost of materials, bridge - building, and constructions under water, and with the working of - the steam engine as it then stood. It happened not unfrequently - that it was desirable to accept the tender of some contractor for - railway work whose prices upon certain items were too high, and - then it became the engineer's business to go into the details and - convince the contractor of his error. On such occasions Brunel - would go step by step through the stages of the work, and it was - curious to see the surprise of the practical man as he found - himself corrected in his own special business by the engineer. - Thus, I remember his proving to an eminent brickmaker who had - tendered for the Chippenham contract that the bricks could be made - much cheaper than he supposed. He knew accurately how much coal - would burn so many bricks, what it would cost, what number of - bricks could be turned out, what would be the cost of housing the - men, what the cartage, and how many men it would require to - complete the work in the specified time. The contractor was - astonished; asked if Mr. Brunel had ever been in the brick trade, - and finally took and made money by the contract at the proposed - figure. - - 'In the case of the Maidenhead bridge, the contractor being alarmed - at learning that the arch was the flattest known in brick, Brunel - pointed out to him that the weight which he feared would crush the - bricks, would be less than in a wall which he, the contractor, had - recently built, and he convinced him by geometry, made easy by - diagrams, that the bridge must stand. Knowledge of detail Brunel - shared with the carpenter, builder, or contractor for earthwork, - and he was their superior in the accuracy and rapidity with which - he combined his knowledge, and arrived at correct conclusions as to - the cost of the work and the time it would take to execute it. - - 'In talking to landowners and others whose opposition it was - important to overcome, I have often been struck by your father's - great powers of negotiation. The most absurd objections--and there - were many such--were listened to with good humour, and he spared no - pains in explaining the real facts, so that it sometimes happened - that he converted opponents into supporters of the railway. In the - course he took there was much skilful diplomacy, but there was no - dishonesty, no humbug. He was very frank and perfectly sincere. His - object was to impart his own convictions, and in that he often - succeeded. - - I never met his equal for sustained power of work. After a hard day - spent in preparing and delivering evidence, and after a hasty - dinner, he would attend consultations till a late hour; and then, - secure against interruption, sit down to his papers, and draw - specifications, write letters or reports, or make calculations all - through the night. If at all pressed for time he slept in his - armchair for two or three hours, and at early dawn he was ready for - the work of the day. When he travelled he usually started about - four or five in the morning, so as to reach his ground by daylight. - His travelling carriage, in which he often slept, was built from - his own design, and was a marvel of skill and comfort. This power - of work was no doubt aided by the abstemiousness of his habits and - by his light and joyous temperament. One luxury, tobacco, he - indulged in to excess, and probably to his injury. At all times, - even in bed, a cigar was in his mouth; and wherever he was engaged, - there, near at hand, was the enormous leather cigar-case so well - known to his friends, and out of which he was quite as ready to - supply their wants as his own. - - His light and joyous disposition was very attractive. At no time - was he stern, but when travelling or off work he was like a boy set - free. There was no fun for which he was not ready. On the old Bath - road, on a Wiltshire chalk hill-side, is cut a large horse, the - pride of the district, and only inferior in reputation to that of - the famous Berkshire vale. The people of the district, afraid to - lose their coach traffic, were violently opposed to the Great - Western Railway Bill. Talking over this one evening, some one - suggested turning the horse into a locomotive. Brunel was much - amused at the idea, and at once sketched off the horse from memory, - roughly calculated its area, and arranged a plan for converting it - into an engine. Ten picked men were to go down in two chaises, and - by moonlight to peg and line out the new figure, and then cut away - the turf, and with it cover up as much of the horse as might be - left. From the tube was to issue a towering column of steam, and - below was to be inserted in bold characters the offensive letters - G. W. R. It was, of course, not intended to carry this joke into - execution, but Brunel often alluded to it, and laughed over the - sensation it would have created. - - 'He possessed a very fine temper, and was always ready to check - differences between those about him, and to put a pleasant - construction upon any apparent neglect or offence. His servants - loved him, and he never forgot those who had stood by his father - and himself in the old Tunnel days of trouble and anxiety. - - 'No doubt the exertions of those three years, though they laid the - foundation, or rather built the fabric, of his reputation, also - undermined his constitution, and eventually shortened his life. - Everything for which he was responsible he insisted upon doing for - himself. I doubt whether he ever signed a professional report that - was not entirely of his own composition; and every structure upon - the Great Western, from the smallest culvert up to the Brent - viaduct and Maidenhead bridge, was entirely, in all its details, - from his own designs.' - -In the press of work and the altered circumstances under which he -superintended the construction of his later railways, many changes -inevitably followed. The open britzska gave place to a close travelling -carriage, which in its turn became useless; and no time was left for fun -or practical jokes; but the same energy of mind and the same kindliness -of heart remained uninfluenced by increasing occupations or advancing -years. - - - - -CHAPTER V. - -_THE BROAD GAUGE._ - - ORIGIN OF THE ORDINARY GAUGE OF RAILWAYS--ADOPTION BY MR. BRUNEL OF - THE BROAD GAUGE ON THE GREAT WESTERN RAILWAY--REASONS FOR ITS - ADOPTION--THE PERMANENT WAY--REPORTS OF MR. NICHOLAS WOOD AND MR. - JOHN HAWKSHAW, 1838--EXTRACT FROM REPORT OF DIRECTORS OF GREAT - WESTERN RAILWAY COMPANY (DECEMBER 20, 1838)--EXTENSION OF THE BROAD - GAUGE SYSTEM--BREAK OF GAUGE--ROYAL COMMISSION ON THE GAUGE OF - RAILWAYS, 1845--LETTER OF MR. BRUNEL ON THE BROAD GAUGE (AUGUST 6, - 1845)--GAUGE ACT OF 1846--THE MIXED GAUGE--REPORT OF RAILWAY - COMMISSIONERS, 1847--NORTHERN EXTENSIONS OF THE GREAT WESTERN - RAILWAY--ADVANTAGES OF THE BROAD GAUGE--PARTIAL ABANDONMENT OF THE - BROAD GAUGE. - - -The railways designed by Mr. Brunel were, with a few exceptions, -distinguished from those in all other parts of England by a peculiarity -in the width between the two rails forming each line of way, or in what -is called the _gauge_. In most railways, the distance between the -internal edges of the rails is 4 feet 8-1/2 inches, being what is termed -the _narrow gauge_; on Mr. Brunel's railways, it was seven feet, or what -is termed the _broad gauge_. - - * * * * * - -The gauge of the earlier railways, which were but a modification of the -old wooden tramway, was made that of the tram plates which they -superseded; and this had been originally fixed to suit the distance -between the wheels of the country carts in the north of England. - -When Mr. George Stephenson introduced the locomotive engine, the gauge -of the lines in the Northumberland district had been already fixed. In -laying out the Stockton and Darlington line (1821-1825) he saw no reason -to depart from the gauge he had previously adopted; and, indeed, some of -the waggons to be used on this line were brought from the -Northumberland collieries. In this way the first important railway in -England was made with the gauge of 4 feet 8-1/2 inches; not from a -deliberate choice of this width on the ground of any peculiar -advantages, but from the mere fact of its already being established -elsewhere. - -In the construction of the Manchester and Liverpool Railway, in 1826, -the same gauge was adopted as on the Stockton and Darlington; this -course was also followed by the Grand Junction and the London and -Birmingham Railways, and thus the 4 feet 8-1/2 inches gauge became -established in that part of the country. - - * * * * * - -Long experience appears to have determined the general type of wheeled -vehicles: the wheels being of somewhat large size, and the body placed -between them, so as to come down close upon the axle-tree. - -This type, which gives obvious advantages in a mechanical point of view, -appears to have been adhered to in all railway vehicles used before the -opening of the Liverpool and Manchester Railway; these, however, were -chiefly coal-waggons. But on the Liverpool and Manchester Railway it was -soon perceived that the great increase of carrying power which the -railway afforded must be met by a corresponding increase of space in the -rolling stock, as it was necessary to accommodate light bulky goods and -passenger traffic. The available width between the wheels was limited to -about 4 feet 6 inches, and to carry in this width any large amount of -cotton goods, or of passengers, would have required a train of an -inordinate length. To meet this difficulty a new form of vehicle was -designed; the wheels were made small, and the body was raised and -widened out, projecting on either side over the tops of the wheels. - -The earliest description of this form of waggon is contained in the -second edition of Wood's 'Practical Treatise on Railroads,' published in -1832, about two years after the opening of the Liverpool and Manchester -Railway. In Plate III., Mr. Wood shows a truck with a raised platform -overhanging the wheels, and adapted for carrying loose boxes of coals; -adding, in the description: - - Although the drawing shows only the form of boxes used for the - conveyance of coals, yet it will readily occur that the form can be - varied to suit the carriage of any kind of articles; the framework - or body of the carriage being raised above the wheels, the breadth - can be extended to any width which the distance between the - railways [i.e. between the up and down lines of road] will admit - (p. 75). - -Such was the state of matters when, in the year 1833, Mr. Brunel was -appointed Engineer of the Great Western Railway. With the view of -leaving the question of gauge open for future consideration, he procured -the omission in the Great Western Act of a clause defining it. He came -to the conclusion that it would be desirable to adopt a wider gauge, and -he recommended this measure to the Directors in a report dated October -1835.[47] - - * * * * * - -In October 1836 a Royal Commission, consisting of Mr. Drummond, -Under-Secretary for Ireland, Mr. R. Griffith, Colonel (now -Field-Marshal) Sir John Burgoyne, R.E., and Professor Barlow, of -Woolwich, was appointed to report on the establishment of railways in -Ireland. They considered carefully the question of gauge, and their -arguments in favour of an increase in the gauge were afterwards stated -by Mr. Brunel to be identical with his own. - -They drew attention to the advantage of large wheels, the use of which -would be facilitated by a wider gauge; and they thought it a matter of -importance to be able to place the bodies of the carriages between the -wheels, instead of over them. - - * * * * * - -It was the width of the carriages, and not the distance between the -rails, that determined the general dimensions, and therefore the cost, -of the works of a railway. Mr. Brunel saw many advantages to be gained -by an increase in the gauge, even while retaining the existing -dimensions of carriages; and he thought it unwise at the commencement of -a work of such magnitude as the Great Western Railway to retain a limit -the inconvenience of which had already become apparent. - -He says, in his evidence before the Gauge Commission: - - Looking to the speed which I contemplated would be adopted on - railways, and the masses to be moved, it seemed to me that the - whole machine was too small for the work to be done, and that it - required that the parts should be on a scale more commensurate with - the mass and the velocity to be attained. (Q. 3924.) - -The width between the rails being the fundamental dimension of 'the -whole machine,' on which its entire development must depend, Mr. Brunel -proposed to begin by the enlargement of this dimension, and recommended -that on the Great Western Railway the gauge should be seven feet. He -considered that the whole of the parts of the railway and of its rolling -stock would be susceptible of continual, though gradual improvement, and -that it was highly advisable to remove, in the outset, a great obstacle -in the way of this progress. - -He did not in the first instance propose any important change in the -details as consequent on the wider gauge; and in regard to one of the -principal points, the diameter of the wheels, he said:-- - - I am not by any means prepared at present to recommend any - particular size of wheel, or even any great increase of the present - dimensions. I believe they will be materially increased; but my - great object would be in every possible way to render each part - capable of improvement, and to remove what appears an obstacle to - any great progress in such a very important point as the diameter - of the wheels, upon which the resistance, which governs the cost of - transport and the speed that may be obtained, so materially - depends. (Report in Appendix I. p. 532.) - -Mr. Brunel also looked forward to the advantages which a wider gauge -would give for the construction of the locomotive engines. Difficulties -had been already experienced from the limited width between the wheels, -which cramped the machinery, rendering it difficult of access for -repairs; it also limited the size of the boiler and fire-box, on which -the power depended. For this reason Mr. Brunel considered that a wider -gauge would present great advantages, as it would allow the locomotives -to be constructed of greater power, and with their machinery arranged in -a more advantageous manner. He also thought that the greater width of -base for the carriages would give increased steadiness and smoothness of -motion, with greater safety, particularly at high speeds, and that there -would be the advantage of being able to use larger wheels for the -carriages. Moreover, he had in view the possibility which the broad -gauge would give of adopting wheels of a still larger diameter without -raising the centre of gravity, the body of the carriage being placed -between them, as in the original type of common road vehicles. - -The broad gauge was also considered by Mr. Brunel in prominent -connection with the peculiarly favourable circumstances of the Great -Western line, in regard to its gradients and curves. He thought that -'it would not have been embracing all the benefits derivable from the -gradients of the Great Western Railway, unless a more extended gauge was -adopted.' In the first place, it was evident that a diminution of the -frictional resistance would present the greatest advantage where the -gradients were flat. In regard to curves, the wider gauge was at that -time considered by him to be more advantageously applied where the -curves were of large radius than where they were sharp.[48] On the Great -Western Railway both gradients and curves were remarkably good; with the -exception of two inclines of 1 in 100, on which auxiliary power was -proposed to be used, there was no gradient between London and Bristol -steeper than 1 in 660, the greater part of the line being nearly level, -and except between Bath and Bristol there was no curve sharper than -about one mile radius. - -For these reasons Mr. Brunel thought that unusually high speed might -easily be attained for passengers, and great tractive power for goods. -He said:-- - - I shall not attempt to argue with those who consider any increase - of speed unnecessary. The public will always prefer that conveyance - which is the most perfect, and speed, within reasonable limits, is - a material ingredient in perfection in travelling. (Report in - Appendix I. p. 532.) - -In deciding that the distance between the rails should be seven feet, -Mr. Brunel seems to have been guided by the principle that the wheels -should be put sufficiently far apart to admit of an ordinary carriage -body being placed between them.[49] - -Mr. Brunel did not anticipate that the difference between the gauge he -proposed and that of other railways would lead to any important -inconvenience. The views he held on this subject were expressed fully by -him in a report of December 13, 1838. He says, speaking of the -difficulty of communication between the Great Western and other -railways:-- - - This is undoubtedly an inconvenience; it amounts to a prohibition - to almost any railway running northwards from London, as they must - all more or less depend for their supply upon other lines or - districts where railways already exist, and with which they must - hope to be connected. In such cases there is no alternative. - - The Great Western Railway, however, broke ground in an entirely new - district, in which railways were unknown. At present it commands - this district, and has already sent forth branches which embrace - nearly all that can belong to it; and it will be the fault of the - company if it does not effectually and permanently secure to itself - the whole trade of this portion of England, with that of South - Wales and the south of Ireland; not by a forced monopoly, which - could never long resist the wants of the public, but by such - attention to these wants as shall render any competition - unnecessary and hopeless. Such is the position of the Great Western - Railway. It could have no connection with any other of the main - lines, and the principal branches likely to be made were well - considered, and almost formed part of the original plan; nor can - these be dependent upon any other existing lines for the traffic - which they will bring to the main trunk. - -Mr. Brunel was not singular in holding the opinion that it would be -desirable to allot a given district to one railway, which might -conveniently serve it by means of a trunk line and branches of a special -gauge. In the Eastern Counties line, designed in 1836, by Mr. -Braithwaite, and opened in 1839, a gauge of 5 feet was adopted; and Mr. -Robert Stephenson, as engineer of another line, the Northern and Eastern -Railway, branching out from the Eastern Counties to the northward, -adopted the same gauge. It was not till the Northern and Eastern line -was extended, some years afterwards, that the rails of the whole system -were altered to the narrow gauge. - - * * * * * - -Mr. Brunel's recommendation was adopted by the Directors of the Great -Western Railway; and, in their report of August 25, 1836, after -observing that the generally level character of the line would greatly -facilitate the attainment of a higher speed of travelling, they pointed -out the advantages of the broad gauge, and stated that engines had been -ordered specially adapted to the nature of the line, which would be -capable of attaining with facility a rate of from thirty-five to forty -miles per hour. - -The line was opened between Paddington and Maidenhead on June 4, 1838, -and the performance of the engines was considered satisfactory, trains -of eighty tons and upwards being drawn at speeds of from thirty-eight to -forty miles per hour. - - * * * * * - -Notwithstanding these favourable results, the change in regard to the -gauge did not pass unquestioned. Attacks were made on it in various -quarters, and considerable excitement was caused among the shareholders -and the public. - -It was asserted that the width of 4 feet 8-1/2 inches was exactly the -proper width for all railways, and that a deviation from it was -tantamount to the abandonment of an established principle which -experience had proved to be correct. It was further alleged that the -cost of all the works connected with the formation of the line would be -greatly increased; that the carriages must be stronger and heavier, -that they would not run round the curves, and would be liable to run off -the rails, and particularly that the increased length of the axles would -render them liable to be broken. These were not advanced as difficulties -which, existing in all railways, might be somewhat increased by the -increase of gauge, but they were assumed to be peculiar to the broad -gauge, and fatal to it. Some urgent representations appear to have been -made to the Directors; for in their report of August 15, 1838, they -state, that as the gauge and the permanent way, which had also been the -subject of adverse criticism, had been sources of some anxiety to them, -they had applied to three of the most eminent authorities on the -construction and working of railways--Mr. James Walker, President of the -Institution of Civil Engineers, Mr. Robert Stephenson, and Mr. Nicholas -Wood, of Newcastle-on-Tyne--to undertake a thorough inspection of the -line, to investigate the working of it, and to give their opinion on the -plan adopted. - -Mr. Walker and Mr. Stephenson declined the task, on the ground that they -did not wish to become embroiled in professional controversy, but Mr. -Wood undertook it; and a similar commission was afterwards given to Mr. -Hawkshaw. - -In order to put the shareholders fully in possession of all the -information in their power, the Directors published a very complete -statement by Mr. Brunel on the arrangements adopted by him. It will be -seen that in this report, which is given in Appendix I. p. 525, he -states his original arguments, and answers the objections brought -against his plans; and he contends that the result of experience -establishes their success. In regard to the gauge, he says:-- - - Everything that has occurred in the practical working of the line - confirms me in my conviction that we have secured a most valuable - power to the Great Western Railway, and that it would be folly to - abandon it. - -But the two engineers, to whom the consideration of this matter had been -referred, differed materially in opinion from Mr. Brunel. The nature of -their investigations and reports, and of Mr. Brunel's replies, is stated -in the extracts given below from the report of the Directors in January -1839. - - * * * * * - -In addition to the question of gauge, another important matter referred -to the consideration of Mr. Wood and Mr. Hawkshaw was the construction -of the permanent way.[50] On the Great Western a construction had been -introduced by Mr. Brunel differing materially from that ordinarily used; -and as defects had shown themselves after the opening of the railway, -some anxiety was felt in reference to it by many of the shareholders. - -The subject of the permanent way adopted on the Great Western Railway -does not necessarily belong to the gauge question, and would, perhaps, -have been more properly considered in the chapter on Mr. Brunel's -railway works; but, as a matter of fact, the controversy concerning it -became so interwoven with that of the broad gauge, that in a historical -account it would be difficult to separate them. - -It appeared to Mr. Brunel that, with a view of applying the engine power -to the greatest advantage, particularly in attaining high speed, more -attention ought to be paid to the construction of the permanent way. He -says, in a report dated February 1837:-- - - It appears to be frequently forgotten that although lofty - embankments and deep cuttings, bridges, viaducts, and tunnels are - all necessary for forming the level surface upon which the rails - are to be laid, yet they are but the means for obtaining that end; - and the ultimate object for which these great works are - constructed, and for which the enormous expenses consequent upon - them are incurred, consits merely of four level parallel lines, not - above two inches wide, of a hard and smooth surface; and upon the - degree of hardness, smoothness, and parallelism (which last has - hitherto been very much neglected) of these four lines depend the - speed and cost of transport, and in fact the whole result aimed - at.... - - In forming all my plans I have looked to the perfection of the - surface on which the carriages are to run, as the great and - ultimate desideratum; and in the detail of construction of this - last operation, without which all the previous labour is - comparatively wasted, I have always contemplated introducing all - the perfection of materials and workmanship of which it is capable. - -With a view to improvement on this point, Mr. Brunel considered it would -be advantageous if two important changes were made. He proposed, in the -first place, to abolish the use of stone blocks for the rails to rest -on, and to substitute timber; and, secondly, to apply the support -uniformly and continuously along the whole length of the rails, instead -of only at intervals. - -The first of these changes, namely, the substitution of timber for -stone, was not wholly new, for transverse wood sleepers were often used -in exceptional situations; but it was the general opinion that stone, -where it could be applied, formed the best support for the rails,[51] -and the exclusive employment of timber was considered a great -innovation. - -The other principle, that of 'continuous bearing,' was similar to that -of the old wooden and stone tramways; and, even as applied to iron rails -it had been extensively used before, as Mr. Brunel mentions in his -report of August 1838 (see Appendix I. p. 535.) - -Mr. Brunel designed for this continuous bearing a peculiar shape of -rail, which, from the form of its section, acquired the name of the -'bridge rail.' The rail was bolted down to the longitudinal timbers, and -the timbers of the two rails were connected together at intervals by -cross-pieces, called transoms, bolted to them; these served to keep the -two rails at a proper distance apart. The longitudinal timbers lay on -gravel or other 'ballast,' which had been found to form the best -foundation, as being firm and solid, easy of adjustment, and allowing -free drainage.[52] - -Mr. Brunel, however, thought there would be difficulty in giving the -longitudinal baulks a sufficiently solid bearing on the gravel below -them. - -A similar difficulty had already been experienced with the heavy stone -blocks used on other railways. As a remedy for this, Mr. Stephenson -caused each block to be lifted and dropped several times on its place, -so as to consolidate the ballast below. - -The same thing could not be done with a long wooden baulk, and Mr. -Brunel therefore contrived another mode of overcoming the difficulty. -Piles were driven into the ground between the rails, and their heads -bolted to the cross-transoms, the object being to hold the timber -framework firmly down. The gravel was then rammed hard under the -longitudinal baulks, to give the consolidation desired. The result, -however, of this mode of construction was far from successful, and the -state of the road, when run over by the trains, was in many places very -defective.[53] - -In the course of his enquiry Mr. Wood tried a large number of -experiments on the Great Western and other lines. He was of opinion that -stone blocks afforded a permanently firmer base, and so caused less -resistance to the train, but that there was less noise with continuous -timber bearings, and that they gave a smoother and a more perfect road -for high rates of speed. He thought, however, that the piles were -objectionable, and that the weight of the trains would in the course of -time sufficiently consolidate the foundation. Mr. Brunel accepted Mr. -Wood's conclusions and abandoned the piling, adopting at the same time -larger timbers and heavier rails. - -The experience of the permanent way, as thus altered, fully justified -the favourable anticipations Mr. Brunel had formed of the continuous -timber bearing.[54] - - * * * * * - -After the reports of Mr. Wood and Mr. Hawkshaw, with Mr. Brunel's -replies to them, had been circulated among the shareholders, a special -general meeting was called in London, to receive and consider these -documents. It was convened for December 20, 1838, but was adjourned till -January 9, 1839. This meeting was of great importance, not only to the -Company, but to Mr. Brunel personally, as on the resolutions to be -passed depended whether or not his plans should be proceeded with. - -He had, however, the warm support of the Directors, as will appear from -the following extracts from their report. - - It may be here concisely stated, that Mr. Wood deduces from - experiments upon the performance of engines on the Great Western - and other lines, that although a higher rate of speed has been - attained on the former, it would appear only to have been - accomplished by the increased power of the engines, with a much - greater consumption of coke when calculated per ton per mile. He - ascribes this result principally to the resistance presented by the - atmosphere to the motion of railway trains, especially at high - rates of speed. His remarks on that subject are qualified, however, - by the expression of a doubt as to the value to be assigned to the - single set of experiments on each of two inclined planes, which are - quoted as the authority for the degree of atmospheric resistance - supposed to have been discovered. - - The reduction of friction by the employment of wheels of increased - diameter, and the benefit of lowering the carriages between the - wheels, are affirmed by Mr. Wood as incontrovertible. The increased - stability, and consequent increased steadiness of motion to - carriages on the wider base, are also admitted by him.... - - The various propositions of doubtful advantage from the wide gauge, - as well as of alleged objection to it, appear to have been - thoroughly considered in the report in question. The experiments on - the consumption of coke at high velocities were unfavourable, and, - in connection with the theory of atmospheric resistance, appear to - have influenced the mind of Mr. Wood to consider that a seven-feet - gauge was beyond the width which he would deem the best. At the - same time, upon a review of all the circumstances, and considering - that there are counteracting advantages, incidental to an increased - width of gauge, he does not think that the result of his enquiries - would justify a change in the dimensions adopted on this line, and - he recommends the present width should be retained. - - The advice thus given by Mr. Wood, upon mature reflection, being - directly at variance with the conclusion at which Mr. Hawkshaw had - previously arrived upon an investigation similarly delegated to - him, it became the duty of the Directors to consider most - attentively the train of reasoning and argument which led the - latter to urge such an opposite course. Naturally expecting from - that circumstance to find in his report a clear and definite - statement of the positive loss or disadvantages accruing from the - increased width of gauge, the Directors could not fail to remark - with some surprise that he enforces his recommendation, not upon - any ascertained injury or failure in the plan, but almost - exclusively upon the presumption that all railways, however - disconnected or locally situated, should be constructed of one - uniform width. While he appears to think that it might be an - improvement to have an addition of a few inches, five or six at the - most, he still questions the expediency of any variation from the 4 - feet 8-1/2 inches gauge. Mr. Hawkshaw, in his report, also considers - any additional expense upon the gauge, as well as upon the - improvement of gradients, to be undesirable, and assumes it at a - scale of augmentation far beyond the real difference of cost. His - estimates on that head are impeached in the engineer's - observations, and no doubt exists in the minds of the Directors, - that the subject, reduced to a mere question of figures, in its - present position, would undeniably show a pecuniary loss to be - borne by the Company by any such change of system as he advocates, - even if it were on other grounds deemed advisable. The objection - that the wide gauge might prevent a junction with other lines seems - both to Mr. Wood and the Directors to have but little weight, as - applied to the Great Western Railway. Already has the same width - been contemplated and provided for in the extension lines through - Gloucestershire to Cheltenham and from Bristol to Exeter. Any local - branches hereafter to be made would undoubtedly follow the same - course, and the proprietors, therefore, may be satisfied that no - apprehension need be entertained by them on that head. - - The advantage of following Mr. Wood's advice, in not making any - alteration in the width of way, has been since most forcibly shown - by more recent experiments, which have entirely changed the results - upon which the chief objections to the gauge were founded. The - performance of the engines, shown by Mr. Wood's experiments in - September, gave such a disproportionate result in their power upon - the attainment of high velocities, as to render it all but - impossible that the effect could be entirely produced by the action - of the atmosphere on the trains. All doubts were shortly removed by - its being ascertained that a different cause (a mere mechanical - defect in the engine itself) had been in operation. If Mr. Wood had - witnessed these recent performances of the engines, he must - unquestionably have changed his opinions as to the means and - practicability of carrying full average loads at a high speed, - without the great increased expense of fuel. The Directors have - satisfied themselves of this very important fact, by personally - attending an experiment (accompanied by several gentlemen, among - whom was a very eminent practical mechanic), on which occasion the - 'North Star' took a train of carriages, calculated for 166 - passengers, and loaded to 43 tons, to and from Maidenhead, at a - mean average speed of thirty-eight miles per hour, the maximum - being forty-five miles per hour, consuming only 0.95, or less than - 1 lb. of coke per net ton per mile, instead of 2.76, say 2-3/4 lbs., - as previously shown. This was accomplished by a mere altered - proportion in the blast pipe of the engine, in the manner explained - by Mr. Brunel, being a simple adaptation of size in one of the - parts, which admits a more free escape of steam from the cylinder, - after it has exerted its force on the piston, still preserving - sufficient draft in the fire.[55] - - It must be almost needless to point out to those who have perused - the reports, how importantly this change bears upon the subject in - almost every relation of the enquiry. It negatives the assumption - that the velocity can only be attained by a ruinous loss of power. - It establishes beyond doubt that the consumption of fuel as now - ascertained, in proportion to the load, is only one-third of that - which from the former experiments had been the basis of Mr. Wood's - arguments. An analysis in the report of the performance of the - Great Western engines, with heavy loads varying from 80 tons to 166 - tons, shows in every respect a peculiarly satisfactory result at a - small cost of fuel, and warrants the expectation of very great - benefit to the Company from the economical transport of goods on - the line. That the expenses of locomotive repairs, especially on - that heavy class of repair which arise from lateral strains on the - wheels and framing of the engines, have been materially less than - on other lines is ascertained by very detailed accounts, accurately - made and submitted to the Board by the superintendent of that - department. The experience of some months has now enabled the - Directors to witness the progressive improvement in the practical - working of the railway. A higher rate of speed has been generally - maintained than on other lines, and at the same time, with that - increased speed, great steadiness of motion has been found in the - carriages, with consequent comfort to the passengers. If speed, - security, and comfort, were three great desiderata in the original - institution of railway travelling, the Directors feel sure that the - public will appreciate and profit by any improvements in those - qualities, the Company deriving ample remuneration in the shape of - increased traffic. A saving of time upon a long journey, with - increased comfort, will necessarily attract to one line in - preference to another many travellers from beyond the ordinary - distance of local connection, and will thus secure a valuable - collateral trade which would not otherwise belong to it. It has - also a decided tendency to avert competition, which may with much - reason be regarded as the chief peril to which railway property is - subjected. - - The Directors, upon a deliberate reconsideration of all the - circumstances affecting the permanent welfare of the undertaking, - divesting the question of all personal partialities or obstinate - adherence to a system, unanimously acquiesce in the abandonment of - the piles, in the substitution of a greater scantling of timber, - and of a heavier rail, retaining the width of gauge with the - continuous timber bearings, as the most conducive to the general - interests of the Company. - -The views of the Directors were approved of by the majority of the -shareholders (the numbers being 7,792 for, and 6,145 against); and the -construction of the line was proceeded with according to Mr. Brunel's -plans. - - * * * * * - -By June 30, 1841, the whole length of the Great Western Railway was -opened from London to Bristol. Some of the Directors' reports mention -the fact that the speed uniformly maintained by the engines much -exceeded the ordinary rate of railway travelling, and allude to the -'general testimony borne to the smoothness and comfort of the line and -carriages.' - - * * * * * - -As has been before mentioned, extensions and branches on the same gauge, -to all of which Mr. Brunel was engineer, were projected and ultimately -carried out, in accordance with the original scheme of the undertaking, -to Exeter, Plymouth, and Cornwall, and to Gloucester, Hereford, and -South Wales, as well as to Oxford, Windsor, and other towns in the -immediate neighbourhood of the line. - -About 1844, the attention of the Company began to be directed to -projects involving extensions of a much more serious character, and -which were destined to have a powerful influence on the position of the -gauge question. During the railway mania, the Great Western Company -found it impossible to stand aloof from the contests which were going on -around them, and thought it necessary, in order to protect their own -interests, to extend their lines beyond the district to which they had -originally intended to confine themselves. - -At the general meeting in August, an extension from Oxford to Rugby was -determined on, as 'of the greatest importance to the Great Western -line.' About the same time a broad-gauge line was promoted from Oxford -to Worcester, and thence by Kidderminster and Dudley to Wolverhampton, -in order to open an immediate communication with the Staffordshire and -Worcestershire districts. There were also rival projects on the narrow -gauge, promoted by the London and Birmingham Company; and the competing -plans were referred, as was the custom at that time, for the examination -of the Railway Department of the Board of Trade. - -In regard to the communication from north to south, through Oxford, the -question was, where the break of gauge should be.[56] The Board of Trade -saw nothing in the relative merits of the gauges to determine this -question, and from commercial considerations, they recommended that the -change of gauge should be made at Oxford. On this and other grounds they -considered that the narrow gauge schemes to the north of Oxford were -preferable to those of the Great Western Railway. - -The rival schemes then went before Parliament, and after a protracted -enquiry, obstinately fought between the parties, the decision was given -in favour of the Great Western lines, contrary to the recommendation of -the Board of Trade. It was, however, stated by the chairman of the -Commons Committee that the decision had been founded on the local and -general merits of the respective lines, without any reference to the -comparative merits of the two gauges. On this account some peculiar -provisions were made in the Acts; for though the lines were sanctioned -on the broad gauge, the proprietors were bound also to lay down narrow -gauge rails upon them, if required to do so by the Board of Trade. At -the same time the House of Commons, on the motion of Mr. Cobden, passed -a Resolution praying her Majesty to refer the gauge question to a Royal -Commission. - -A Commission was issued in July; the Commissioners being three in -number--Sir J. M. Frederic Smith, R.E.; Mr. G. B. Airy, Astronomer -Royal; and Professor Barlow, of the Royal Military Academy, Woolwich. -They took a large amount of evidence, both oral and documentary, and -made some examinations of the working of the two gauges. Their report -was presented to Parliament early in the session of 1846. - -Of forty-eight witnesses, thirty-five were advocates of the narrow -gauge; and against these were arrayed but four champions of the broad -gauge, all officers of the Great Western Railway:--Mr. Charles Alexander -Saunders, the secretary; Mr. Seymour Clarke, the traffic superintendent; -Mr. (now Sir Daniel) Gooch, the locomotive superintendent; and Mr. -Brunel. - -The report was of considerable length, and in it the Commissioners -addressed themselves to three heads of enquiry, viz.:-- - -1. Whether the break of gauge was an inconvenience of so much importance -as to demand the interference of the legislature. - -2. What means could be adopted for obviating or mitigating such -inconvenience. - -3. Considerations on the general policy of establishing a uniformity of -gauge throughout the country. - -The general conclusions arrived at on these points were thus summed up -by the Commissioners:-- - - 1. That, as regards the safety, accommodation and convenience of - the passengers, no decided preference is due to either gauge, but - that on the broad gauge the motion is generally more easy at high - velocities. - - 2. That, in respect of speed, we consider that the advantages are - with the broad gauge; but we think the public safety would be - endangered in employing the greater capabilities of the broad gauge - much beyond their present use, except on roads more consolidated, - and more substantially and perfectly formed, than those of the - existing lines. - - 3. That, in the commercial case of the transport of goods, we - believe the narrow gauge to possess the greater convenience, and to - be the more suited to the general traffic of the country. - - 4. That the broad gauge involves the greater outlay, and that we - have not been able to discover, either in the maintenance of way, - in the cost of locomotive power, or in the other annual expenses, - any adequate reduction to compensate for the additional first cost. - - Therefore, esteeming the importance of the highest speed on express - trains for the accommodation of a comparatively small number of - persons, however desirable that may be to them, as of far less - moment than affording increased convenience to the general - commercial traffic of the country, we are inclined to consider the - narrow gauge as that which should be preferred for general - convenience, and therefore, if it were imperative to produce - uniformity, we should recommend that uniformity to be produced by - an alteration of the broad to the narrow gauge.... - -Guided by the foregoing considerations, the Commissioners recommended -that 4 feet 8-1/2 inches should be fixed by law as the standard gauge of -the country; and that as to the existing broad gauge lines, either they -should be altered to the narrow gauge, or some course adopted which -would admit of narrow gauge carriages passing along them.[57] - -This adverse report was a great surprise to the supporters of the broad -gauge system, as rumours had led them to hope for a different result. -Immediately after its appearance, several documents were published, -containing powerful and severe strictures on the proceedings and -opinions of the Commissioners. The most important of these was written -by Mr. Saunders, Mr. Daniel Gooch, and Mr. Brunel. It occupied fifty -closely printed folio pages, and was entitled, 'Observations on the -Report of the Gauge Commissioners, presented to Parliament.' To this, -'Supplemental Observations' were added, after the publication of the -Evidence and the Appendix to the Report. - -In the conclusion of the 'Observations' the writers gave a summary of -the points they considered to have been proved in the controversy, -namely-- - - * * * * * - -That the question of 'break of gauge' originated as a cloak to a -monopoly. - -That even if the gauge were uniform, through trains would be -impracticable. - -That the transfer would be of little inconvenience. - -That any advantage of small waggons was applicable to the broad gauge, -but that the advantage of large waggons was not applicable to the -narrow. - -That the competition between the two systems was advantageous. - -That the final recommendations of the Commissioners were at variance -with their separate conclusions. - -That it would be unjust to refuse to allow the broad gauge to be laid -down on lines for which it was already sanctioned by Parliament. - -That the enquiry before the Commissioners was not properly conducted, -and that consequently no legislation ought to be founded on it. - -That the data published by the Commissioners were often wrong, and in -some cases led to the reverse of their conclusions. - -That greater economy was proved on the broad gauge. - -That the broad gauge was superior in the points of safety, speed, and -conveyance of troops. - -That the experiments made in the presence of the Commissioners had -demonstrated beyond all controversy the complete success of the -broad-gauge system. - -For these and other reasons, a strong protest was made against any -legislative interference with the broad-gauge system. - -A reply was published to these arguments; and during the controversy a -large number of pamphlets, articles, and other publications appeared on -both sides. - - * * * * * - -Mr. Brunel's views on the whole question, about this time, are concisely -expressed in the following letter, written to a friend in France, who -asked for information on the subject of the broad gauge:-- - - - August 4, 1845. - - I am just off for Italy, but write a few hasty lines in reply to - Mons. ----'s queries, and which you must scold him for not - addressing direct to me. Nobody can answer such questions but - myself, and I am compelled to be very brief. - - In answer to the _first_, I send a drawing. - - _Secondly._ I see no reason why the ordinary construction of - rails, chairs, and sleepers should not be equally applicable to - the wide gauge as to the narrow. I have used them occasionally. I - should think 75 lbs. per yard heavy enough for any purposes. - - _Thirdly._ Within all ordinary limits, certainly in curves of more - than 250 metres [12-1/2 chains] radius, the gauge does not affect the - question of curves. The effect of a curve of larger radius than - this appears, both from much observation as from theory, to arise - merely from _two_ causes, the one centrifugal force, which is - easily neutralised, and is independent of gauge; the other from the - axles not being able to travel in the direction of the radius, and - consequently the wheels not running in a tangent to the curve. This - also is unaffected by the width of gauge. Practically I believe the - conditions are not altered. - - _Fourthly._ The expenses of construction are not dependent on the - breadth of gauge unless the total width allowed for the loads or - carriages is thereby or for other reasons increased, which is not a - necessary consequence of a seven-feet gauge. - - The wide gauge could be laid upon the London and Birmingham Railway - without altering any of the works, but in constructing the Great - Western Railway I thought it desirable to provide for carrying - larger bodies, and I placed the centres of the two railways 13 feet - apart, instead of 11 feet, and therefore my railway became _four_ - feet wider in total width. - - The increased cost of this, including the cost of land, will vary - from 300_l._ to 500_l._ per mile. - - _Fifthly._ The increase of width will not increase the weight of an - engine (of the same power) 500 lbs., but I avail myself of the - larger width to get more powerful engines, and they weigh, with - water in the boiler, 18 to 21 tons. I send a drawing of one; the - stroke is 18 inches. - - _Sixthly._ The passenger carriages are all on six wheels, and - excessively strong; at present the framework of carriages and the - whole of the waggons are made of iron. The first-class carriages - weigh, with wheels, &c., 7 tons 16 cwt. (17,472 lbs.), and carry 32 - passengers. Second-class about the same weight, and hold 72. - - _Seventhly_ and _Eighthly_. The comparison being on different - railways under different managements and totally different - circumstances, no strictly correct comparative results can be - given; and of course the most opposite opinions are entertained and - expressed. I believe we travel much quicker at the same cost and - with more ease, and certainly the wear and tear of engines and - carriages is _very much less_ with us than with the other lines; - but for the reasons above stated it cannot be made matter of exact - proof, but remains matter of opinion. - -The report of the Gauge Commission, on being presented to Parliament, -was referred by the House of Commons to the Board of Trade, who reported -on it in June 1846. They did not, however, concur with the Commissioners -to the full extent of their recommendations; for, while admitting the -break of gauge to be an evil, they could not, having regard to the -circumstances under which the broad gauge companies had been -established, and the interest they had acquired, recommend either that -the broad gauge should be reduced to narrow, or that rails should be -laid down for narrow gauge traffic over all their lines. Such measures -would involve great expense, and they were unable to suggest any -equitable mode of meeting it. - -This conclusion necessarily affected the opinion of the Board of Trade -in regard to the several lines under construction connected with the -Great Western Railway, which the Board recommended should be all made on -the broad gauge. - -In regard to the broad-gauge lines sanctioned by Parliament from Oxford -to Rugby, and from Oxford to Worcester and Wolverhampton, the Board -determined to exercise their powers in requiring the narrow gauge to be -laid down, in addition to the broad. - -The House of Commons adopted the recommendations of the Board of Trade, -and passed a series of resolutions in conformity thereto, and 'An Act -for regulating the Gauge of Railways' received the Royal Assent on -August 18, 1846. - -It was enacted that it should not be lawful to construct any new -passenger railway on any other gauge than 4 feet 8-1/2 inches in England, -and 5 feet 3 inches in Ireland. - -Exceptions, however, were made in favour of certain lines in the west of -England and South Wales. - -The provisions relating to the gauge in the Acts for the Oxford and -Rugby, and the Oxford, Worcester, and Wolverhampton Railways, were left -in force. - -The Act also generally excepted 'any railway constructed or to be -constructed under the provisions of any present or future Act containing -any special enactment defining the gauge or gauges of such railway or -any part thereof.' - -This Act, while it professed to establish the narrow gauge as the -standard throughout the kingdom, did so only nominally; in reality, by -the words 'present or future,' in the passage above quoted, it left the -question of the gauge of any new railway open for the consideration of -the committee on the particular bill; and it only obliged the promoters -of the undertaking to adopt the narrow gauge when no case could be -proved by them for the adoption of some other. This was equivalent to -the former state of things, so that all the agitation of the question -had ended in a mere expression of opinion, and the broad-gauge party -were not only left with all their former liberty, but were encouraged, -and almost compelled, to push their system still farther wherever they -could. - - * * * * * - -About the time of the passing of the Gauge Act, a Board of Commissioners -of Railways was established, to whom the powers formerly possessed by -the Board of Trade were transferred. - -One of the first duties of the Commissioners was to provide for the due -compliance with the order of the Board of Trade respecting the -introduction of the narrow gauge, in conjunction with the broad, on the -Oxford and Rugby Railway. - -It was proposed to effect this either by laying a narrow gauge line -concentrically between the two rails of the broad gauge, or by laying -down only one additional rail between the two broad-gauge rails, making -one of the latter serve for both broad and narrow gauges. Mr. Brunel -recommended the second of these plans to be adopted on the Oxford and -Rugby line. - -After a careful consideration of the question, the Commissioners -sanctioned the mixed gauge formed by the introduction of a third rail; -this was accordingly laid down, and none of the dangers which were at -the time prognosticated in reference to it were found to exist. It has -been the plan almost exclusively used in the many cases where the -combination of the two gauges has been required. - - * * * * * - -In 1846 the Great Western Railway Company had promoted a bill for a -branch to Birmingham from the Oxford and Rugby line at Fenny Compton. -The Act was obtained, but they were defeated on the question of the -gauge. However, after the passing of the Gauge Act, the Company again -attempted to carry the broad gauge to Birmingham. Their application was -backed by a strong memorial from the districts interested, and in June -1847 an order was passed by the House of Lords directing the Board of -Commissioners of Railways-- - - To inquire into the accommodation afforded by the several lines of - railway now open, or in the course of construction, or projected, - between London and Birmingham; and to report to this House, early - in the ensuing Session of Parliament in what manner they are of - opinion that the interests of the public may be most effectually - ecured in regard to such lines; and whether it is expedient that - the broad gauge should be extended to Birmingham; and if so, in - what manner such an arrangement can be carried into effect with the - least interference with existing interests.... - -This, of course, opened up again the whole question of the comparative -merits of the two gauges. - -The Railway Commissioners issued a series of queries addressed to the -officials of the Great Western and the London and North Western Railway -Companies, and others. On the part of the Great Western, answers were -given by Mr. Brunel and Mr. Daniel Gooch. Mr. Gooch also furnished the -results, with tables and diagrams, of a very comprehensive series of -dynamometrical experiments, made by him on a mile of straight and level -line on the Bristol and Exeter Railway. These experiments fully -demonstrated the advantages of the broad gauge, and are still the chief -authority on train resistances.[58] - -In their report the Commissioners adopted the opinion of the Gauge -Commissioners 'that a break of gauge was a most serious impediment in -the transport of merchandise, and that the broad gauge did not offer any -compensating advantage so far as that description of traffic was -concerned.' In regard, however, to passenger traffic, they found a case -for further enquiry. They said-- - - It is notorious that higher speeds, with larger and heavier - passenger trains, are regularly maintained on a part of the line of - the Great Western Railway than on any other railway in the country. - This fact is known and greatly appreciated by a very large portion - of the public; and no opinion respecting the extension of the - district within which the broad gauge should be adopted is likely - to be received with confidence which is not founded on a full - consideration of the circumstances to which the above fact is to be - attributed, and of the extent to which, under differing - circumstances, if attributable to the breadth of gauge, the gauge - of the Great Western Railway offers this advantage (p. 11). - -They assumed that the greater speed was due to greater engine power, and -they admitted that the increase of gauge allowed of an increase in the -size and power of the locomotive. They arrived at the result that the -broad-gauge engine 'can draw on a level an ordinary 'passenger train of -60 tons with as much facility at 'sixty miles an hour as the -narrow-gauge engines can at 'fifty,' the advantage, however, diminishing -with steep gradients. In their report the following passages are to be -found:-- - - Such appear to the Commissioners to be the advantages which the - broad gauge at present offers; and although they cannot consider - them sufficient to compensate the evils attendant on two gauges, if - it were now possible to obtain uniformity of gauge, yet, as two - gauges are established, it appears to them that it might be - expedient, and for the public interest, on account of those - advantages, to extend the broad gauge to Birmingham ... (p. 14.) - - By introducing the mixed gauge on the Birmingham and Oxford - Junction Railway, the line from Birmingham by Fenny Compton to - London would probably offer, as a broad-gauge railway, as rapid a - communication as the existing direct line;[59] and great as the - advantages which the public have received by the rivalry between - the gauges, in the rapid improvement in railway travelling, have - been, it might even be expected that these would be further - increased when the two systems are brought into direct competition, - which as yet they have not been (p. 16). - -The report of the Railway Commissioners was presented in May 1848. Their -decision was ratified by the passing of an Act in the same session for -extending the broad gauge from Oxford to Birmingham; and the line was -opened in October 1852. - -Beyond Birmingham the Great Western Company purchased existing railways -leading through Wolverhampton and Shrewsbury to Chester, and obtained -access to Birkenhead and Manchester. It thus secured a communication -with the great Lancashire towns and the manufacturing districts. - -But all the lines north of Wolverhampton had been constructed on the -narrow gauge, and therefore, unless the broad gauge had been laid down -on these lines, there was a break of gauge between the northern -districts and London. - -The break of gauge was found to be a much more serious evil than had -been anticipated by the Great Western Company when they were fighting -their great battle in 1845. For passengers the inconvenience was -unimportant; but for the goods traffic between the manufacturing towns -and London it was serious, partly on account of the expense, but more -especially in consequence of the loss of time. The delay of some hours -by change of waggons, where great competition existed, was fatal. - -For these reasons the abolition of the break of gauge became desirable. -The number of narrow-gauge lines had by the year 1861 been so increased -that there was no longer any hope of advantageously extending the broad -gauge in the north. Therefore the mixed gauge was completed to London. - -After the establishment of the narrow-gauge communication on the -northern lines of the Great Western, and its prolongation to London, -there was but little inducement to use the broad gauge north of Didcot. - - * * * * * - -So far as it extended, the broad gauge had exhibited in a marked degree -the advantages Mr. Brunel claimed for it, and which were neither few nor -unimportant. - -It may be desirable before concluding this chapter to sum up those -advantages:-- - -1. It gave the power of constructing more powerful engines, by which -greater speed for passenger trains and greater tractive power for heavy -goods trains were obtained.[60] - -2. It gave more space for the convenient arrangement and beneficial -proportions of the machinery, as well as for convenient access to it. In -all these points difficulties had been found on the narrow gauge; and -the compulsory restriction of so important a dimension as the width -between the rails has been a bar to any improvements of great magnitude -or comprehensive nature. - -3. It gave, even with the overhanging carriage, the facility for -obtaining large wheels, and consequently diminishing the axle friction -without sacrifice of stability. - -4. The greater width of base for the carriages to rest on gave increased -steadiness and smoothness of motion, particularly at high speeds. It was -the impulse given by the increase of speed and comfort obtained without -difficulty on the broad gauge, which had led to the chief improvements -introduced in railway travelling. - -5. Greater safety was secured, particularly at high speed, from the -greater stability of position due to the wider base, producing increased -steadiness and diminishing the chance under exceptional circumstances of -the derangement of any part of the train. - -6. While the broad gauge was but little more costly than the narrow, the -width of the works being determined not by the width of the rails, but -by the width of the carriages, and the extra cost of rolling stock -being very small,[61] the broad gauge could be worked more economically -under parallel circumstances than the narrow. - -7. It gave the facility of using broader vehicles with equal steadiness, -in cases where the extra breadth would be useful, though the extra -breadth was by no means an essential part of the scheme. - - * * * * * - -The truth of these assertions, as establishing the superiority of the -broad gauge, was of course vehemently denied by the advocates of the -narrow gauge. - -One objection urged by them, the inconveniences of the break of gauge, -has undoubtedly been proved by experience to be a very powerful one, so -powerful indeed as to compel the abandonment of the broad gauge on the -lines where any considerable quantity of goods traffic has to be carried -in competition with other companies. - -Had Mr. Brunel's original plan been carried out, and had the broad-gauge -companies taken possession of all the western portions of England, and -avoided extensions into the north, the points of contact would no doubt -have been so unimportant that no great inconvenience would have arisen, -or a few miles of double gauge would have removed any difficulty; but, -under the actual circumstances of the case, the Great Western Company -were forced to yield. - - * * * * * - -The advantages of the broad gauge were so much appreciated by the -districts it served, that its abandonment was viewed with considerable -displeasure, particularly in the neighbourhood of Birmingham; but the -inconvenience of double traffic arrangements far outweighed the -advantages derivable from the use of the broad gauge, to the limited -extent it could be applied on those outlying portions of the Great -Western system. For these reasons the Company came to the determination -to work their northern lines on the narrow gauge only. - -The broad gauge is therefore now confined to the district for which it -was originally intended. Even in this district there are many points of -contact with the narrow gauge; but the inconveniences of break of gauge -are by no means so important as they were in the north, and do not, at -present at least, menace the continued existence of Mr. Brunel's -design. - - - - -CHAPTER VI. - -_THE ATMOSPHERIC SYSTEM._ - -A.D. 1840--1848. AETATIS 35--43. - - PRELIMINARY OBSERVATIONS--THE SOUTH DEVON RAILWAY--DESCRIPTION OF - THE ATMOSPHERIC SYSTEM--HISTORY OF ITS INTRODUCTION PRIOR TO - 1844--REPORT BY MR. BRUNEL, RECOMMENDING ITS ADOPTION ON THE SOUTH - DEVON RAILWAY (AUGUST 19, 1844)--EXAMINATION OF THIS REPORT--MR. - BRUNEL'S EVIDENCE BEFORE THE SELECT COMMITTEE ON ATMOSPHERIC - RAILWAYS, 1845--HISTORY OF THE APPLICATION OF THE SYSTEM ON THE - SOUTH DEVON RAILWAY, 1844-1848--REPORT ON STATE OF WORKS (AUGUST - 28, 1847)--REPORT ON CAUSES OF FAILURE (AUGUST 19, - 1848)--ABANDONMENT OF THE SYSTEM, SEPTEMBER - 1848--_NOTE_--COMPARISON OF STATIONARY AND LOCOMOTIVE POWER. - - -In the year 1844 Mr. Brunel recommended the adoption of the Atmospheric -System of propulsion on the South Devon Railway, a line of 52 miles in -length, which he was then constructing between Exeter and Plymouth. This -system had, under the management of Messrs. Clegg and Samuda, been in -operation with success on the Dalkey line for some time before Mr. -Brunel adopted their apparatus on the South Devon Railway. After it had -been in use on the South Devon for about twelve months, it was -abandoned, and the railway worked throughout by locomotives. - - * * * * * - -It is therefore as important as it is interesting to examine the causes -of the failure of the Atmospheric System, and to consider the reasons -which induced Mr. Brunel in the first instance to adopt it, and -afterwards to recommend its abandonment. - - * * * * * - -Up to about the year 1843, the cost of railways, which was in a great -measure due to the conditions imposed by the limited capabilities of the -locomotive, had prevented their construction, except in cases where they -would secure a large traffic, and at the same time traverse what was -then considered a practicable country. - -A curvature of one mile radius was regarded as the maximum generally -admissible on a line where high speeds were aimed at, and auxiliary -locomotives were required to work heavy gradients. - -Nevertheless, by the growing wants of the public and the growing -boldness of engineers, the railway system was gradually being forced -into districts hitherto regarded as unsuitable for it; and no country -was held to be impracticable where the gradients could be surmounted by -the inconvenient and costly expedient of auxiliary power. - - * * * * * - -The south of Devon had for several years demanded railway accommodation, -and at the period now under review, Mr. Brunel projected what was called -the coast line. This line, while it best accommodated the population of -the district, passed through a very difficult country. If it was to be -constructed at a moderate cost, curves of a quarter of a mile radius had -to be admitted; and above 30 miles of its entire length traversed a -district involving the adoption of gradients steeper than had been -elsewhere used for such considerable distances. The Act for this railway -was obtained in the Session of 1844. - - * * * * * - -The South Devon Railway, on leaving Exeter, crosses the flat country on -the right bank of the river Exe, as far as Starcross, a village nearly -opposite to Exmouth. From this point it runs down to the coast and along -the sea-shore, by Dawlish, to Teignmouth; being protected by a sea-wall -for the greater part of the distance, and passing through several -headlands by short tunnels. Beyond Teignmouth it follows the left bank -of the river Teign, which it crosses a short distance before reaching -the station at Newton Abbott. The portion of the line from Exeter to -Newton--21-1/2 miles in length--is very nearly level, the steep inclines -for which the railway is noted being west of Newton. Between Newton and -Totness, for the first mile and a half the line is almost level, and in -the next two miles it rises 200 feet, with gradients of 1 in 100, 1 in -60, and nearly a mile of 1 in 43. At the summit is a short tunnel; and -thence the line descends 170 feet in a mile and three-quarters, with -gradients of 1 in 40 and 1 in 43 for about three-quarters of a mile, and -gradients of 1 in 57 and 1 in 88 for the rest of the incline. It then -runs with more moderate gradients and about a mile and a half of level -line to Totness. - -From the valley of the Dart at Totness the line rises at once by a rapid -ascent of 350 feet in four miles and a half, with gradients varying from -1 in 48 to 1 in 90, more than a mile and a half averaging 1 in 50. -Thence it runs, with easy up and down gradients, for a distance of 12 -miles along the skirts of Dartmoor, crossing by lofty viaducts the deep -valleys which penetrate the moor. It then descends to Plympton, in the -valley of the Plym, falling 273 feet in a little more than two miles, -with a gradient of 1 in 42-1/2. From Plympton the line for two miles is -level, and then rises on an incline of 1 in 80 for a mile and a half, -and descends by a similar gradient into the Plymouth station. - -The main characteristics of the railway are that, while it traverses a -very heavy country, its principal changes of level are concentrated into -four long and steep inclines. These four inclines were intended to be -worked by auxiliary power. - -Hitherto on gradients of unusual steepness a stationary engine with rope -traction had been generally regarded as the only available expedient; -but the special difficulties by which this system was encumbered -rendered it unsuitable for high-speed passenger traffic, and practically -inapplicable to an extended line. It had, however, been very -successfully employed by Mr. Robert Stephenson on the Blackwall Railway, -a line of about 3-3/4 miles in length. - -Messrs. Clegg and Samuda, the projectors of the Atmospheric System, -which was another mode of using stationary power, had, previously to -this period, laboured to attract the attention and win the favourable -opinion of engineers and the general public. - - * * * * * - -It is desirable, before proceeding further, to give a brief description -of this system of traction, upon the merits of which distinguished -engineers entertained widely different opinions. - -Between the two rails of the line of way was laid a cast-iron tube, -which on the Croydon and Dalkey railways and the completed or level -portion of the South Devon Railway was fifteen inches in diameter. On -the inclines it was proposed to use a twenty-two inch tube. - -At intervals of about three miles along the line were erected stationary -engines, working large air-pumps, by means of which air could be -exhausted from the tube, and a partial vacuum created within it. A -close-fitting piston was placed in one end of the tube, and the air -being exhausted from it, the pressure of the external air on the surface -of the piston which was towards the open end of the tube forced the -piston through the tube towards the end where the air-pumps were -working; so that if the piston were connected with a carriage running on -the rails, it would draw the carriage with it. The connection between -the piston and the carriage was arranged by Messrs. Clegg and Samuda in -the following way:[62] Along the top of the tube was a slit about 2-1/2 -inches wide; this slit was closed by a long flap of leather, which was -strengthened with iron plates, and secured to the tube at one side of -the slit. One edge of the leather thus formed a continuous hinge; the -other edge, where it closed on the tube, was sealed with a composition -of grease, to render it air-tight. This flap was known by the name of -the longitudinal valve. - -When the valve was closed, the air could be exhausted from the tube in -front of the piston, and a partial vacuum formed. Behind the piston, the -air being at atmospheric pressure both within and without the tube, -there was no objection to opening the longitudinal valve; and a bar, -extending downwards from the under side of the carriage, entered the -slit obliquely under the opened valve, and was connected to the rear end -of a frame about ten feet long, the front end of which carried the -piston. To allow the bar to pass along the slit, the valve was opened on -its hinge, being pressed upwards by a series of wheels carried by the -moving piston-frame inside the tube. The valve closed again after the -passage of the train; and the tube was ready to be exhausted in -preparation for the passage of the next train.[63] - -The Atmospheric System was first tried in 1840. An experimental tube was -laid down at Wormwood Scrubs on part of the short line now incorporated -into the West London Railway, and then known by the title of the -Bristol, Birmingham, and Thames Junction Railway. Its working was the -subject of eager discussion among engineers. - -In 1842 Sir Frederic Smith, R.E., and Professor Barlow, under an order -from the Board of Trade, reported so favourably on the system with -reference to the proposal for its application on the Dalkey branch of -the Dublin and Kingstown Railway, that it was adopted there. In 1843 Mr. -(afterwards Sir William) Cubitt determined to employ it on the Croydon -Railway; and about the same time Mr. Robert Stephenson was desired by -the Directors of the Chester and Holyhead Railway to report on the -propriety of introducing it on that line. - -Mr. Stephenson's report was based on a series of experiments on the -working of the system at Dalkey. The view he took was adverse to its -adoption, not only on the Chester and Holyhead, but on almost every -railway whatsoever; and this on the ground that, though it was quite -capable of being developed into a practical working system, yet on lines -with ordinary gradients the atmospheric traction must be considerably -more costly than locomotive traction, and on steep gradients than rope -traction; in other words, that, as a mechanical appliance it was, though -practicable, not economical. - -Mr. Stephenson's report had no sooner appeared than the correctness of -his conclusions was disputed on his giving evidence before a Committee -of the House of Commons, in the spring of 1844, on the Croydon and -Epsom Railway Bill. - - * * * * * - -Mr. Brunel also was summoned as a witness. Previously to this time he -had taken a great interest in the various attempts which had been made -to introduce the Atmospheric System, and he had himself conducted -experiments at Wormwood Scrubs and at Dalkey. As early as July 1840 he -had considered its applicability to the Box Tunnel incline on the Great -Western Railway. He had also considered it in reference to various -projected lines; and in 1843 he recommended it for adoption in a long -tunnel on one of the steep inclines of the Genoa and Turin Railway, the -success of the system being then (he wrote) sufficient to justify its -use on a part of the line protected from weather. It was not, however, -applied on this railway.[64] - -Mr. Brunel's views at this time are indicated in the following letter:-- - - - April 8, 1844. - - Any part I have taken in examining into the system has been purely - from the desire which I always feel to forward good inventions; and - when I have formed a decided opinion, no fear of the consequences - ever prevents my expressing it. My great anxiety, however, is to - see a line of railway and all its appurtenances made expressly for - the Atmospheric System, and worked accordingly; until this is done - the results will be comparatively unsatisfactory. - -Although unwilling to express general opinions, Mr. Brunel spoke -strongly before the Croydon and Epsom Railway Committee in favour of the -advantages of the Atmospheric System under certain circumstances, and -approved of its use on that line. - -A few months later Mr. Brunel recommended the Directors of the South -Devon Railway Company to adopt the Atmospheric System, and they resolved -to act on his advice. - -His report was as follows:-- - - - August 19, 1844. - - I have given much consideration to the question referred to me by - you at your last meeting--namely, that of the advantage of the - application of the Atmospheric System to the South Devon Railway. - - The question is not new to me, as I have foreseen the possibility - of its arising, and have frequently considered it. - - I shall assume, and I am not aware that it is disputed by anybody, - that stationary power, if freed from the weight and friction of any - medium of communication, such as a rope, must be cheaper, is more - under command, and is susceptible of producing much higher speeds - than locomotive power; and when it is considered that for high - speeds, such as sixty miles per hour, the locomotive engine with - its tender cannot weigh much less than half of the gross weight of - the train, the advantage and economy of dispensing with the - necessity of putting this great weight also in motion will be - evident. - - I must assume also that as a means of applying stationary power the - Atmospheric System has been successful, and that, unless where - under some very peculiar circumstances it is inapplicable, it is a - good economical mode of applying stationary power. - - I am aware that this opinion is directly opposed to that of Mr. - Robert Stephenson, who has written and published an elaborate - statement of experiments and calculations founded upon them, the - results of which support his opinion. - - It does not seem to me that we can obtain the minute data required - for the mathematical investigation of such a question, and that - such calculations, dependent as they are upon an unattained - precision in experiments, are as likely to lead you very far from - the truth as not. - - By the same mode M. Mallet and other French engineers have proved - the success of the system; and by the same mode of investigation - Dr. Lardner arrived at all those results regarding steam - navigation and the speed to be attained on railways, which have - since proved so erroneous. - - Experience has led me to prefer what some may consider a more - superficial, but what I should call a more general and broader - view, and more capable of embracing all the conditions of the - question--a practical view. - - Having considered the subject for several years past, I have - cautiously, and without any cause for a favourable bias, formed an - opinion which subsequent experiments at Dalkey have fully proved to - be correct; viz. that the mere mechanical difficulties can be - overcome, and that the full effect of the partial vacuum produced - by an air-pump can be communicated, without any loss or friction - worth taking into consideration, to a piston attached to the train. - - In this point of view the experiment at Dalkey has entirely - succeeded. A system of machinery which even at the first attempt - works without interruption and constantly for many months, may be - considered practically to be free from any mechanical objection. - - No locomotive line that I have been connected with has been equally - free from accidents. - - That which is true for one railway of two miles in length is - equally true for a second or third, although they may be placed the - one at the end of the other; the chances of an accident are only in - the proportion of the number, or in other words, the length, a - proportion which holds equally good with locomotives, except that a - locomotive may be affected by the distance it has previously run, - while a stationary engine and its pipes cannot in like manner be - affected by the previous working of the neighbouring engine and - pipes. - - In my opinion the Atmospheric System is, so far as any stationary - power can be, as applicable to a great length of line as it is to a - short one. - - Upon all these points I could advance many arguments and many - proofs, but I shall content myself with saying that, as a - professional man, I express a decided opinion that, as a mechanical - contrivance, the Atmospheric apparatus has succeeded perfectly as - an effective means of working trains by stationary power, whether - on long or short lines, at higher velocity and with less chance of - interruption than is now effected by locomotives. - - I will now proceed to consider the question of the advantage of its - application to the South Devon Railway. - - It will simplify the discussion of the question very much if it is - considered as a comparison between a double line worked by - locomotives in the usual manner, and a single line of railway - worked by stationary power, the only peculiarity of the present - case being that upon four separate portions of the whole 52 miles - stationary assistant power would under any circumstances have been - used, these four inclines forming together one-fifth of the whole - distance. - - It is necessary to consider it as a question of a single line on - account of the expense, the cost of the pipe for each line being - about 3,500_l._ per mile. - - An addition of 7,000_l._ per mile, or of about 330,000_l._, in the - first construction could not be counterbalanced by any adequate - advantage in the saving in the works on the South Devon Railway, - and probably not by any subsequent economy or advantage in the - working; but the system admits of the working with a single line, - without danger of collision, certainly with less than upon a double - locomotive line. And I believe also that, considering the absence - of most of the causes of accidents, there will even be less - liability of interruption and less delay in the average resulting - from accidents than in the ordinary double locomotive railway. - - By the modification of the gradients and by reducing the curves to - 1,000 feet radius where any great advantage can be gained by so - doing, and by constructing the cuttings, embankments, tunnels, and - viaducts for a single line, a considerable saving may be effected - in the first cost. - - In the permanent way and ballasting, the reduction will be about - one-half. I should propose to make the rails about 52 lbs. weight - and the timber 12 x 6; the quantity of ballast would probably be - rather more than half, but at the present prices of iron and timber - the saving could not be less than 2,500_l._ per mile. - - From a careful revision of the works generally, I consider that a - reduction may be effected in the following items, and to the amount - specified in each, viz., ballasting gradients and curves:-- - - L s. d. - - Reduction in earth work 16,500 0 0 - - " in length of principal tunnel 14,000 0 0 - -------------- - 30,500 0 0 - - _Saving by single line._ - - Earthwork 25,000 0 0 - - Tunnels 11,500 0 0 - - Viaducts 15,000 0 0 - - _Permanent way and ballast._ - - To allow for sidings, say 50 miles, 2,500_l._ 125,000 0 0 - --------------- - 207,000 0 0 - =============== - - _Per contra._ - - L - Pipe on 41-1/2 miles[65] 138,500 - Increase on inclined planes, 10-1/2 miles 6,500 L s. d. - 145,000 0 0 - Engines for the 41-1/2 miles 35,000 0 0 - Patent right, say 10,000 0 0 - --------------- - 190,000 0 0 - =============== - The difference in first cost therefore is 17,000 0 0 - To this must however be added the cost of the - locomotive power, with its attendant expenses - of engine-houses, &c., which cannot, I think, - be put at less than 50,000 0 0 - -------------- - Making a saving of 67,000 0 0 - - I have not included in the expense of the Atmospheric apparatus - that of the telegraph, because at its present reduced cost of - 160_l._ per mile I am convinced its use would repay the outlay in - either case. - - It would appear, then, that the line can be constructed and - furnished with the moving power, in working order, on the - Atmospheric System, for something less than the construction only - of the railway fitted for the locomotive power, but without the - engines; and that taking into consideration the cost of locomotive - power, a saving in first outlay may be effected of upwards of - 60,000_l._ - - But it is in the subsequent working that I believe the advantages - will be most sensible. - - In the first place, with the gradients and curves of the South - Devon Railway between Newton and Plymouth, a speed of thirty miles - per hour would have been, for locomotives, a high speed, and under - unfavourable circumstances of weather and of load, it would - probably have been found difficult and expensive to have maintained - even this; with the Atmospheric, and with the dimensions of pipes I - have assumed, a speed of forty to fifty miles may certainly be - depended upon, and I have no doubt that from twenty-five to - thirty-five minutes may be saved in the journey. - - Secondly, the cost of running a few additional trains so far as the - power is concerned is so small, the plant of engines, the - attendance of engine-men, &c., remaining the same, that it may - almost be neglected in the calculations; so that short trains, or - extra trains with more frequent departures, adapted in every - respect to the varying demands of the public, can be worked at a - very moderate cost. I have no doubt that a considerable - augmentation of the general traffic will be thus effected, by means - which with locomotive engines would be very expensive, and - frequently unattainable, particularly as regards one class of short - trains, whether for passenger or goods, which from the - inconvenience of working them by locomotives are hardly known--I - refer to trains between the intermediate stations. - - By many means, which the easy command of a motive power at any - time, at every part of a line, must afford of accommodating the - public, I believe the traffic may be increased. - - It appears to me also that the quality of the travelling will be - much improved; that we shall attain greater speed, less noise and - motion, and an absence of the coke dust, which is certainly still a - great nuisance; and an inducement will thus be held out to those - (the majority of travellers) who travel either solely for pleasure, - or at least not from necessity, and who are mainly influenced by - the degree of comfort with which they can go from place to place. - - Lastly, the average cost of working the trains will be much less - than by locomotives. - - With the gradients of the South Devon Railway, and assuming that - not less than eight trains, including mail and goods trains, - running the whole distance, and certainly one short train running - half the distance, be the least number that would suffice, I think - an annual saving of 8,000_l._ a year in locomotive expenses, - including allowance for depreciation of plant, may very safely be - relied upon. - - For all the reasons above quoted, I have no hesitation in taking - upon myself the full and entire responsibility of recommending the - adoption of the Atmospheric System on the South Devon Railway, and - of recommending as a consequence that the line and works should be - constructed for a single line only.[66] - -In this report Mr. Brunel rested his recommendation principally on two -assumptions, which he held to be indisputable--(1) That stationary -power, if freed from incumbrances such as the friction and dead weight -of a rope, was superior to locomotive power; and (2) That the -Atmospheric System of traction was theoretically a good and economical -method of applying stationary power, and that it was also a practical -and working system, as had been shown in its first and somewhat crude -application at Dalkey. - -The superiority of stationary as compared with locomotive power depends -on two principles--(a) That a given amount of power may be supplied by a -stationary engine at a less cost than if supplied by a locomotive. (b) -That the dead weight of a locomotive forms a large proportion of the -whole travelling load, and thus inherently involves a proportionate -waste of power--a waste which is enhanced by the steepness of the -gradients and the speed of the trains. - -A detailed examination of these principles is given in the note to this -chapter. - -It is there shown that at the time referred to stationary power could be -obtained for one farthing per horse-power per hour, while locomotive -power cost more than one penny per indicated horse-power per hour, the -cost of the locomotive power being more than four times that of the -stationary power. On a level line at a speed of 60 miles per hour, for -each horse-power usefully employed, a locomotive, in consequence of its -own dead weight and the friction of its machinery, is obliged to expend -more than one and a half horse-power; in this case, therefore, the -useful work done costs nearly seven times as much as if it had been -performed by a stationary engine. Again, on so moderate an ascent as one -in 75, for each horse-power usefully employed, the locomotive has to -expend at 40 miles per hour more than two horse-power, and at 60 miles -per hour three horse-power; so that the useful work done costs in the -one case nearly ten times, in the other thirteen times, as much as if -it had been performed by a stationary engine. - -This great advantage of stationary over locomotive power was a -sufficient justification for introducing a system which promised to -realise it to any considerable extent; although many difficulties might -have to be encountered. - -As has been already stated, Mr. Brunel had satisfied himself that the -Atmospheric System was theoretically economical, and that its trial at -Dalkey had shown that it was practically free from mechanical -objections. Mr. Stephenson, indeed, had admitted that the mechanical -details had been brought to a remarkable degree of perfection; but this -admission was not any qualification of the radical difference of opinion -which existed between him and Mr. Brunel, to which Mr. Brunel drew -attention in his report of August 1844. - -The subsequent abandonment of the Atmospheric System led many to believe -that Mr. Brunel had been rash in rejecting the detailed investigations -and conclusions of Mr. Stephenson, and that the adverse conclusions -which Mr. Brunel had refused to entertain were subsequently established. - -But, in fact, the failure of the Atmospheric System was due to failure -in some of its mechanical details, and was not due to those inherent -defects in its principle which Mr. Stephenson in his report considered -that his experimental data had established. - -Mr. Brunel's opinions were again brought prominently into notice in the -evidence given by him before a Select Committee of the House of Commons, -which was appointed in the Session of 1845, in consequence of the number -of projected lines which it was proposed to work by the Atmospheric -System. - -The following letter, written by Mr. Brunel to one of the members of the -Committee, explains what he considered to be his position at this -time:-- - - - April 3, 1845. - - I am summoned to attend your Committee on Friday, and as it is - known that I have expressed opinions favourable to the Atmospheric - System, and that I am actually applying it upon a line of some - length, it would be considered an absurd affectation, and would, - moreover, be useless to attempt, to avoid giving evidence when so - called upon; but I am a most unwilling witness. I think it rather - hard upon a professional man, who wishes to be cautious and - prudent, that he should be called upon to express general opinions, - which, if written even in the most studied and careful language, - cannot be so worded as to be applicable to every case that may - hereafter arise, or to be proof against the unfair and unscrupulous - attack of the paid writers on these controversies. I mention these - difficulties, which I feel that you may make some allowances for, - if my feelings should appear in my evidence, or if that evidence - should appear to fall very short of the opinions I am known to - entertain, and which I must entertain to induce me to apply the - system extensively, as I am doing. I find it difficult to define - the points upon which it would be desirable to examine engineering - witnesses, and I really believe that, entering freshly upon the - subject and feeling as one of the public, you are more likely to - elicit the useful points than one who, like myself, has been - turning his whole attention (lately, at least) solely to the - mechanical construction. However, I enclose a copy of a letter I - addressed to a party interested in the patent, which refers to my - opinions on the several points--opinions, however, expressed - without that caution to which I referred as so necessary. - -(_Enclosure._) - - - March 31, 1845. - - I object very much to giving evidence upon the abstract point of - the applicability of a particular system, and thus furnishing - general opinions which others are to apply as they may choose to - particular cases; and if I could, I would refuse to give evidence - at all before the present Committee, whatever might be the - consequence to the promoters of the Atmospheric System. - Circumstances, however, render such a refusal impossible; but I am - equally anxious not to be drawn into becoming an advocate of a - system. - - When I gave evidence last year,[67] although it was then very much - against my inclination, it was in support of a particular case; and - it was only incidentally that my opinion was advanced as to a - system. The evidence is now avowedly sought in support of a system, - and I do not, as I before stated, intend to become an advocate of - this or any other system. I mention these my views to prevent - disappointment. If the following facts and opinions are likely to - be of use to the Committee, I can give evidence on them. - - I made experiments upon the portion of railway laid on Wormwood - Scrubs. These experiments were made for my own private - satisfaction, and not made public in any way. - - They satisfied me of the mechanical practicability of the system. - - In 1843 and 1844 I made several experiments upon the Dalkey - railway. - - The result of my observations and of those experiments is an - opinion that the mechanical difficulties attending the application - of this system may be overcome, and the whole as a machine made to - work in a very perfect manner; that is, as a mechanical power for - locomotion it will generally, but not in every case, be more - economical than what is strictly called locomotive power, that high - speeds may be more easily attained, that, from the absence of the - locomotive engine, the rails may be constructed and maintained in - more perfect order, and as a consequence the carriages may be - constructed and worked in a more perfect manner, and so as to run - more smoothly, and that in all respects the travelling may be - rendered more rapid, more luxurious, and more safe. As regards the - last, viz. safety, collisions may be rendered altogether - impossible, or most remotely possible; while all other sources of - danger, now very small, may be almost entirely removed by the - increased perfection of the rails. - - As regards first cost, a single line may be made to answer all the - purposes of a double locomotive line for most railways, except main - lines in immediate connection with the metropolis, or forming trunk - lines for others with important branches not under the same - control; and a single Atmospheric line will generally cost as - little, often less, including the working power, than a double - locomotive line without the engines. I am now constructing a line - of 52 miles in length entirely for the Atmospheric System. I - already see many advantages to be attained in the setting out and - constructing of a railway, if originally designed for this system; - the principal advantages can only be attained, and, above all, the - principal difficulties in the system can only be properly provided - against, where the line is originally designed for the system; the - choice of gradients and curves and levels, the position, and, above - all, the arrangements of stations, will generally be totally - different in the two systems, and the difficulties to be avoided - will equally differ. - -It is unnecessary to give any extracts from Mr. Brunel's evidence,[68] -as it only repeats the opinions and calculations embodied in his report -of August 1844. - -The Committee, while they allowed that experience could alone determine -under what circumstances of traffic or of country the preference to the -Atmospheric or the Locomotive System should be given, reported very -strongly in favour of the general merits of the Atmospheric System. - -As soon as it had been decided that the South Devon was to be -constructed as an Atmospheric line, the dimensions of the cuttings, -embankments, and tunnels were arranged for a single line, except on the -long incline west of Totness, and on that east of Plympton. In the -approaches to the principal summits the gradients were made somewhat -steeper, so as to reduce the excavations. - -In December 1844, Mr. Brunel prepared a specification and drawing of a -steam-engine and vacuum pump, and a copy was sent to the most eminent -engine-builders, together with a letter inviting tenders for six pairs -of engines. The letter concluded as follows:-- - - Any party whose tenders may be accepted, shall, if required, - furnish forthwith a more detailed drawing and specification of the - engines as they propose to furnish them; the specification and - drawing now sent being expressly made very general, in order that - each manufacturer may, so far as is consistent with the general - requisites and conditions, adopt his own methods of construction, - or use any existing patterns. - -The economical character of the engines which Mr. Brunel desired to -obtain is sufficiently indicated by the requirement that they were to be -high-pressure condensing engines, fitted with double-seated expansion -valves, and having boilers proved to 100 lbs. per square inch, and -guaranteed to work with safety valves loaded to 40 lbs. per square inch. - -The tenders accepted were those of Messrs. Boulton and Watt, Messrs. -Rennie, and Messrs. Maudslay and Field. - -Mr. Brunel left it to the contractors to prepare their designs without -any interference on his part, deeming it best to rely on their -unfettered judgment. - -The task of manufacturing and fitting the cast-iron tube was one of some -difficulty, the longitudinal slit allowing of considerable distortion in -the casting. This work was undertaken by Mr. George Hennett, by the aid -of a set of very effective tools devised by Mr. T. R. Guppy. - -The tubes were supplied at the rate of one mile per week, and by the -middle of 1846 nearly the whole line was laid to Newton, and the valve -was ready to be fixed. - -In the autumn of 1846, Mr. Joseph Samuda went to Dawlish, taking with -him a staff of assistants trained in the working of the system at -Croydon; and every effort was made to advance the completion of the -engines and the other parts of the apparatus. - -Owing, however, to vexatious delays in the erection of the engine-houses -and engines, it was not until the commencement of 1847 that a -piston-carriage was able to traverse the first six miles out of Exeter. -And, though repeated experimental trains continued to be run, no -passengers had been conveyed by Atmospheric trains prior to the general -meeting of the shareholders, at the end of August. Mr. Brunel's report -on this occasion was as follows:-- - - - August 27, 1847. - - It is a subject of great regret, and to no one more than to myself, - that we have as yet been unable to open any portion of the line to - the public with the Atmospheric apparatus, although a considerable - distance has for some months been in a state to admit of frequent - experiments being made upon it. This delay has arisen principally, - if not entirely, in that part of the whole system which it might - have been expected would have been the least exposed to it--namely, - the construction and completion of the steam-engines. - - It is due to Mr. Samuda that I should say that, so far as regards - the mere pipe and valve, and other details which may be said to - constitute the Atmospheric apparatus, we might long since have - commenced. But the engines, although designed without any - interference with their plans, and furnished by the best makers of - the country, and although differing so slightly from the ordinary - construction of steam-engines, have proved sources of continued and - most vexatious delays, both in the unexpected length of time - occupied originally in their erection, and in subsequent correction - of defects in minor parts. While the engines were imperfect, it - would not only have been unwise to have commenced working the line, - even had it been practicable, but the frequent interruptions to the - continuous working of all the engines rendered it impossible to - complete and test the different portions of the Atmospheric - apparatus. There are still some defects to be remedied in one or - two of the engines, and I am using every endeavour, by persuasion - and by every other means in my power, to urge on the manufacturers - in their work of completion. Within the last week or two only have - we been able to work at all continuously between Exeter and - Teignmouth, so as to have the opportunity of trying the different - parts, and getting the various details requisite for actually - working trains tested and brought to sufficient perfection to - ensure efficiency and regularity. - - Since the beginning of last week, however, four trains per day have - been run regularly, stopping at the stations, and keeping their - time as if working for traffic. The tube and valve appear in good - order, and the whole has worked well, but the running in this - manner can alone show the deficiencies which may still exist in the - details necessary for stopping, and starting quickly from the - stations, and all the other minor operations incidental to working - the traffic in the ordinary course; and, until all these - arrangements are completed, and the engines in more perfect order, - I think it would be much better to defer at least the substitution - of the Atmospheric for the locomotive working. Trains, in addition - to those now running may perhaps be advantageously worked for the - public, after a further short continuance of the present - practising. - - The two engines completing the number to Newton are nearly ready - for trial, and it is to be presumed that, after the experience of - the past, the makers will be enabled to put them at once into an - efficient state. - - The delays and difficulties attending the bringing into operation - the Atmospheric System upon this portion of the railway have been - beyond all anticipation, and beyond what any previous experience - would have justified anybody in anticipating. The difficulties have - all been seriously aggravated by the necessity (consequent, - certainly, upon the original delays) of working the line with - locomotives during the construction and completion of the - Atmospheric apparatus. Not only has the constant occupation of the - line interfered with the progress of the work, but it has been - necessary to devise all the arrangements so as to admit stations, - sidings, and line being worked either by locomotive or by - Atmospheric in succession, or even at the same time. - - These difficulties, added to those always consequent upon the - introduction of any new system, have been most wearying and - incessant, and I am not surprised that the public and the - proprietors should have been impatient. I trust the ultimate result - will remove any grounds for disappointment. - -The stress of personal anxiety and personal fatigue, experienced by Mr. -Brunel and by all who were engaged in the work, was very severe, and -continued so to the end. Not only was the progress in the completion of -the work slow, but in spite of every exertion the results were -incessantly marred by unfortunate contingencies which involved further -delay, discouragement, and expenditure. Moreover, the reaction which -followed the railway mania had set in; calls were ill responded to, and -great difficulty was experienced in raising the money requisite for the -completion of the line. - -Under these circumstances it was resolved, on September 1, not to incur -any new expenses in relation to the Atmospheric System beyond Totness, -and to limit any expenditure already contracted for, until its working -between Exeter and Totness had been fairly tried, except to provide -assistant power up the two inclines. - -On September 8 the Atmospheric trains began to take their share in the -passenger duty of the line, four trains running each way daily; and, -except when occasional mishaps caused delay, the new mode of traction -was almost universally approved of. The motion of the train, relieved of -the impulsive action of the locomotive, was singularly smooth and -agreeable; and the passengers were freed from the annoyance of coke dust -and the sulphureous smell from the engine chimney. - -In other respects the record of progress is but a chequered one, and -exhibits, in spite of great and able efforts and brightening intervals -of occasional improvement, indications of growing difficulties deepening -into ultimate defeat. - -In examining the chronicle of events which correspondence and memoranda -supply, it is inevitable that references to failure and disaster should -be found relatively in far greater abundance than records of success; -and this for the simple reason that there was at that time great use in -taking note of the unfavourable incidents that occurred, almost none in -mentioning successful work. - -There is therefore some danger of falling into a mood of unjust -depreciation, such as Mr. Brunel had in energetic terms urged the -Directors to guard themselves against. He protested against their -requiring (as they once intended to do)-- - - continuous and detailed reports--if true and honest, of course - containing nothing but accounts of mishaps--of a system which (he - says) we are struggling to render perfect. Why, a daily account of - our locomotive mishaps would ruin the locomotive system, if it were - new! I will undertake to say that the mishaps of yesterday or - to-day on the Great Western Railway were as great as that of - Tuesday on the South Devon. - -The Atmospheric System was vaguely credited with every delay which a -train had experienced in any part of its journey; though, in point of -fact, a large proportion of these delays was really chargeable to that -part of the journey which was performed with locomotives. It often -happened that time thus lost was made up on the Atmospheric part of the -line, as is shown by a record of the working, which is still extant. In -the week, September 20-25, 1847, it appears that the Atmospheric trains -are chargeable with a delay of 28 minutes in all; while delays due to -the late arrival of the locomotive trains, amounting in all to 62 -minutes, were made up by the extra speed attainable on the Atmospheric -part of the line. - -Not unfrequently, however, casualties occurred; due indeed to remediable -causes, but yet of discouraging aspect in themselves, and deriving -additional weight from the manner in which they reacted on the cost of -working. Such, for instance, were the frequent and occasionally very -serious breakages in essential parts of the pumping-engines. Again, the -cupped leathers of the travelling-piston, which made it air-tight, were -often destroyed while it was passing the various inlet and outlet -valves. Improvements in the valves were introduced to meet this -difficulty; but the remedy could not be applied at once throughout the -line, and much inconvenience was thus experienced, and a considerable -expense incurred. Another source of inconvenience was the water which at -times accumulated within the tube. - - * * * * * - -In many respects the results which had been calculated on were realised, -and the new arrangements necessary to the working of the system were -successfully brought into operation. - -The speed of the trains corresponded fully with the degree of vacuum -obtained; that is to say, the train resistances proved to be what had -been anticipated.[69] - -After the trial of a great variety of air-pump valves, a form was -adopted which was found to answer exceedingly well.[70] - -In the Atmospheric tube, the system of self-acting inlet and outlet -valves, by which the piston was enabled to leave the tube on approaching -a station and enter it again on recommencing its journey, were, on the -whole, successfully adapted to their duty. - -Again, an arrangement for starting the train rapidly from the station, -without the help of horses or of locomotives, had been brought -practically into operation. This arrangement consisted of a short -auxiliary vacuum tube containing a piston which could be connected with -the train by means of a tow-rope, and thus draw it along till the -piston of the piston carriage entered the main Atmospheric tube. Some -accidents at first occurred in using this apparatus, but its defects -were after a time removed; and it is hardly to be doubted that the -various minor difficulties of the Atmospheric System could soon have -been effectually mastered. - - * * * * * - -It now remains to show how it was that, in spite of much that was -hopeful, a vigorously sustained contest ended in defeat, instead of -being prolonged into victory. - -In working the Atmospheric System on the South Devon Railway grave -difficulties were throughout encountered, for which to the last only -imperfect remedies could be found. - -As regards the power consumed, the engines of each pumping station -worked up to about 236 indicated horse-power, and their regulated duty -for each train, including the anticipatory pumping, was equivalent to -5.5 minutes of work for every mile of the length of tube they had to -exhaust. As the running speed averaged 40 miles per hour, or a mile in -1.5 minutes, the 236 horse-power during the 5.5 minutes of pumping must -be regarded as equivalent to 865 horse-power during the actual passage -of the train. Now, making full allowance for piston friction and extra -friction on curves, for the power expended in getting up speed, for the -excess of air-pump resistance due to the changes of temperature -experienced by the air under exhaustion, and even for the very large -actual amount of friction in the engines employed, the work done should -have been represented by an expenditure of 240 horse-power during the -passage of the train. If to this is added an allowance for leakage, such -as the experiments at Dalkey indicated would be amply sufficient with -the longitudinal valve in good condition, it may be said that Mr. -Brunel had a right to expect that the duty would be performed with an -expenditure of 300 horse-power; whereas it actually required 865 -horse-power, or nearly three times the amount. - -The explanation of this waste is simple. - -Serious and unexpected causes of failure developed themselves in the -longitudinal valve, and led to an excessive amount of leakage. A great -part of the normal duty of the engines was, as has been stated, to -exhaust the tube previous to the entry of the train; and when, owing to -leakage, the amount of air to be so pumped out was greatly increased, it -became necessary that the operation should be commenced much earlier. -There was thus a longer time during which the leakage could take place, -and a still greater amount of air to be pumped out. It therefore -followed that a large increase of leakage involved waste of power in an -enormously increased proportion. - -The length of time occupied by the anticipatory pumping was often -increased by the difficulty of arranging proper telegraphic -communication on the South Devon Railway, and by the absence of it on -the Bristol and Exeter Railway. The Electric Telegraph was in its -infancy, and though Mr. Brunel had been the first to apply it in -connection with railways, namely, between London and Slough on the Great -Western Railway in the year 1839, it was not brought into perfect -working order on the South Devon Railway till the Atmospheric System was -on the point of being abandoned. The result of the defects in the -telegraph was that, when a train was late, warning was not received at -the several engine-houses;[71] and thus, when this was the case, the -pumping-engines which had been started at the right interval of time -before the train was due, had to be kept at work for a needlessly long -period pumping out the air, which was all the while leaking in through -the deteriorated valve. This inefficiency of the telegraphic apparatus -would have been of trifling importance but for the defects of the valve. -Had the valve been as perfect as it was expected to be, the vacuum, -after it had been formed, could have been maintained by an expenditure -of power very moderate in comparison with that which was actually -required. - -As regards the relative cost of the power consumed, it appears that, -owing to imperfections in the engines, their expenditure of fuel per -indicated horse-power was more than double that of the best of the -Cornish pumping-engines, to which they were analogous; while the cost of -working was more than three times as great. - -The defects in the engines were for the most part such as might have -been remedied; and this would have been done, had not the excessive duty -imposed on them by the leakage of the longitudinal valve prevented their -being stopped for repairs and alterations. In this way the defects of -the different parts of the apparatus mutually aggravated each other. - -It appears then that, chiefly owing to the defective longitudinal valve, -the engines were expending nearly three times the power which they -should have done for a given tractive duty, according to previous -experience, and the results obtained on the Dalkey line, and that they -cost per horse-power at least three times as much as was expected. - -The cost of traction, nearly nine times as much as had been calculated -on, was between two and a half and three times what it would have been -with locomotive power; and this was on a level part of the line, where -the comparative advantages of the Atmospheric System were not exhibited -as they would have been in the part which had steep gradients. - -The imperfections of the longitudinal valve have now to be described. By -its condition the Atmospheric System had to stand or fall. With an -efficient valve, the defects of the other parts of the apparatus would -have been of minor importance, and time would have been given for -remedying them. When the leakage became considerable, the defects of the -telegraph and the defects of the engines alike assumed a formidable -aspect. - -The failure of the valve was due, partly to the composition which was -used to seal the joint where it opened, and partly to the material of -which the valve consisted. The difficulty of obtaining a suitable -composition was the first which had to be encountered. On the South -Devon a lime soap was eventually found to answer the purpose well. Its -surface, however, from exposure to light and air, formed into a hard -skin; and to remedy this a thinner and more fluid material, a compound -of cod-oil and soap, was laid on to keep it soft. This answered -satisfactorily, but it required frequent renewal, as it was apt to be -drawn into the tube by the rush of air when the valve was opened. The -renewal of the various compositions, and the careful examination and -repair which the valve constantly required, was a cause of great anxiety -and expense. - -But in the materials of the valve lay the source of the more serious -difficulty. - -The ready affinity of leather for oil and grease, and its suppleness and -closeness of grain when saturated with substances of that nature, had -long been known and utilised. It had not been anticipated how readily, -with air-pressure on one side and a partial vacuum on the other, the -oily matters with which the leather was charged would escape from it, -especially in the presence of water. Although, while the leather was -saturated with water, the valve was remarkably air-tight; when frost -supervened the water became frozen, and gave a fatal stubbornness of -texture, which rendered the valve incapable of closing properly. Again, -in long-continued drought the leather became intractable from its -dryness; and the stiffening, whether from frost or drought, rendered it -liable to be torn. An immediate application of seal-oil penetrated the -leather, and relaxed its stiffness; but the remedy often could not be -applied in time, and, moreover, was expensive. - -A still more grave defect was all the while becoming matured, and was -undermining every hope that a suitable dressing could be discovered, and -that the longitudinal valve might be made perfect. - -Under the joint action of water in the leather, and of the affinity of -iron for tannin--and on the enduring presence of tannin within its -texture the consistency of leather depends--a destructive decomposition -had long been at work; the oxide, established in the iron plates of the -valve by continued contact with damp leather, had been steadily -abstracting the tannin; thus the leather had become converted into an -ink-stained and comparatively decomposed tissue. Large portions of it -became torn, and incurably pervious to air. - -It was not until early in June 1848 that Mr. Brunel discovered the -condition which the valve had assumed. He then instituted a careful -examination throughout the line, and the extent of the disorder was -realised. - -The state of things which existed when this discovery was made in effect -involved the renewal of the valve the whole distance from Exeter to -Newton; so that, as the cost of the valve was 1,160_l._ per mile, an -immediate outlay of some 25,000_l._ became essential to the maintenance -of the system, and this at the time when the real difficulties of the -valve question had become most apparent. By galvanising the iron plates -of the valve the mutually destructive action of the iron and the leather -might have been prevented; but a remedy was also required for the other -serious defect which leather, as the material of the valve, was found to -exhibit, namely, its tendency to become permeable to air after -long-continued use under air-pressure, owing to the inward escape of the -material with which it had been dressed. - -These difficulties were not only such as had not been anticipated, but -such as no one was justified in anticipating. - - * * * * * - -It now became necessary for Mr. Brunel to consider what course, under -the circumstances, it was most advisable for the Company to adopt. - -A Committee of the Board was appointed to examine the whole question; -and, at their desire, Mr. Brunel made a report upon it, which was as -follows:-- - - - August 19, 1848. - - You have called upon me to report to you upon the present state of - the Atmospheric apparatus, and particularly upon the circumstances - connected with the partial destruction of the longitudinal valve - which has lately occurred, and the probability of remedying this - serious defect, and of keeping the valve in repair and in good - working order. - - Such a report involves necessarily the consideration of the whole - question of our experience of the working of the Atmospheric - System; because, to arrive at any clear appreciation of the present - state of the apparatus, I must refer to the circumstances which - have affected our working up to the present time, and particularly - to the several difficulties which we have had to encounter and - their effects. - - The first difficulty, and one which was as unexpected as it was - serious, was in the working of our stationary engines. Upon the - efficiency of these machines must of course ultimately depend the - economy and efficiency of the working of the whole system, however - perfect in itself might be the Atmospheric apparatus. Accordingly, - great precautions were taken--precautions which I still think such - as to justify the expectation that we should secure the best - engines that could be made. - - The three first manufacturers of the day were employed--Messrs. - Maudslay (who had had some experience in this particular branch, - having made the engines for the Croydon railway), Messrs. Boulton - and Watts, and Messrs. Rennie. They prepared their own designs; and - I know that they each bestowed much thought in the preparation of - these designs, and took considerable interest in the results. - - Mr. Samuda, a man of considerable mechanical abilities, having all - the experience that could be had upon the subject, and deeply - interested in the success of the engines, was also employed to - superintend their manufacture. - - Notwithstanding all these precautions, notwithstanding excellent - workmanship, these engines have not, on the whole, proved - successful; none of them have as yet worked very economically, and - some are very extravagant in the consumption of fuel, burning - nearly double the quantity of others, while the average is very - considerably more than it ought to be. - - The apparent causes of this excess are various in the different - engines, but all resulting more or less apparently from the want of - experience in this particular application of power, and from the - circumstance of the form of the engines being somewhat novel, and - involving slight differences in the proportion and arrangement of - the parts; and the consumption of steam being greater than was - calculated upon, it has been obtained by a more wasteful - expenditure of fuel, and the evil has been aggravated. - - The difficulty of remedying this state of things has been increased - by the consequence of defects in the Atmospheric apparatus, which, - causing a much greater demand upon the working of the engines, has - delayed, or has entirely prevented, our throwing an engine out of - work, to introduce the requisite improvements. - - Still, so far as this defect in the engines is concerned, there is - no doubt that it is susceptible of considerable, if not complete - remedy, and that a reduction of one-third may be effected in the - consumption of fuel. - - In the Atmospheric apparatus itself our difficulties have been more - numerous. - - We have suffered from extreme cold, particularly when it followed - quickly upon wet. - - We have suffered from extreme heat, and also from heavy falls of - rain. These difficulties have in turn been encountered and - gradually overcome, and I think the effects of all these causes - upon a valve in good condition may now be obviated, if not - entirely, yet so much so as to render their operation unimportant. - - The same remedy applies to all three--keeping the leather of the - valve oiled and varnished, and rendering it impervious to the - water, which otherwise soaks through it in wet weather, or which - freezes in it in cold, rendering it too stiff to shut down; and the - same precaution prevents the leather being dried up and shrivelled - by the heat; for this, and not the melting of the composition, is - the principal inconvenience resulting from heat. A little water - spread on the valve from a tank in the piston-carriage has also - been found to be useful in very dry weather, showing that the - dryness, and not the heat, was the cause of leakage; but a new - difficulty has arisen, and a new defect has been discovered, one - much more serious in its extent and its possible consequences, and - one which renders the operation of each of the previously mentioned - causes of difficulty much more powerful and mischievous. - - Within the last few months, but more particularly during the dry - weather of last May and June, a considerable extent of longitudinal - valve failed by the tearing of the leather, at the joints between - the plates; the leather first partially cracked at these points, - which causes a considerable leakage, particularly in dry weather; - after a time it tears completely through, and that part of the - valve is destroyed, and requires to be replaced. - - A considerable extent has thus been replaced, but the whole of the - valve is more or less defective from this cause; the amount of - leakage is considerable, and the working altogether inefficient. I - have examined carefully portions of the valve that have been - removed, and I find that at the part which has given way the - texture of the leather seems to be destroyed--it is black, and has - evidently been acted upon by the iron of the plates. - - Upon some parts of the line the injury seems to be more general - than upon others; but it is very difficult to examine the valve in - place, so as to form any correct opinion of the extent of the evil. - - As regards the cause of this defect, Mr. Samuda, who under his - contract is at present liable for the repair of the valve, urges - that the valve was kept for a length of time in cases after it was - delivered to the Company, and that, exposed to damp, and the oil - in the leather not being renewed on the surface, the iron may have - rusted, and the leather have been injured; and he refers to - instances lately observed, in which valves taken out of the top of - a case which had been exposed to wet do show similar signs of - injury. - - Supposing, however, this assumption to be correct, it would not - seem to affect the question of his liability. He suggests also, as - a cause, that the valve remained for a length of time in place - without been used and even worked over by locomotive engines, which - prevented its being properly oiled and attended to; that the evil - has been aggravated by an attempt to reduce too much the use of oil - to the leather; and, lastly, that the piston-gear has been allowed - to get out of adjustment, so that the leather of the valve has been - strained. - - I shall not, however, here enter into the discussion of this - question of liability, but confine myself to the consideration of - the evil, and the possibility of remedying it. - - Of the extent of the evil, for the reason I have given, it is - impossible to form any accurate opinion; it is impossible, - therefore, to say that it does not extend more or less over the - whole distance, excepting, of course, that which has been already - replaced. That which is injured cannot be repaired in place, but - must be removed, and the remedy can only be applied in the new - valve. - - It is quite possible that a valve made in the same manner as the - present, if properly attended to from the first, and with our - present experience, might not be subject to this destruction, and - Mr. Samuda states that such is the case at Dalkey; but I do not - think that I could rely upon this result. By painting, but, better - still, by zincing or galvanising the iron plates, and making them - overlap a short distance, both the chemical and the mechanical - action of the plate upon the leather appears to be prevented, and I - believe, therefore, that this evil may be remedied at a small - increased cost in any new or repaired valve that might be laid - down: but of the existing valve I can say no more than I have done. - It is not now in good working condition, and I see no immediate - prospect of its being rendered so. - - From the foregoing observations, it will be evident that I cannot - consider the result of our experience of the working between Exeter - and Newton such as to induce one to recommend the extension of the - system. - - I believe that if the longitudinal valve were restored, the working - expenses might be immensely reduced; that the quantity of fuel - consumed which is the great item of expense, may be diminished by - one-third; that the price of the fuel, which now costs 18s. per ton - at the engine-houses, ought to be reduced at least 12 per cent.; - and that the total cost may thus be brought down to a moderate - amount, such as I had originally calculated upon. But the cost of - construction has far exceeded our expectations, and the - difficulties of working a system so totally different from that to - which everybody, traveller as well as workmen, is accustomed, have - proved too great; and therefore, although, no doubt, after some - further trial, great reductions may be effected in the cost of - working the portion now laid, I cannot anticipate the possibility - of any inducement to continue the system beyond Newton. - - With respect to the future working of the apparatus between Exeter - and Newton, I feel in great difficulty as to expressing any - opinion, seeing that a very large expense has been incurred, and - believing, as I do, that the cost of working may be so very much - reduced; but that reduction can only be effected by the almost - entire renewal of the valve, and by some expenditure in the - engines. And unless Mr. Samuda or the patentees undertake the - first, and extend considerably the period during which they would - maintain it in repair, and unless they can offer some guarantee for - the efficiency of that valve, I fear that the Company would not be - justified in taking that upon themselves, or incurring the expense - attending the alteration of the engines. - - I believe that for the inclined planes, as an assistant power, the - apparatus will be found applicable and efficient; and as the - engines and the pipes are nearly ready at Dainton, it may be found - desirable to try it there, provided a satisfactory arrangement can - be entered into for the maintenance and efficiency of the valve. - - I have not referred to our great disappointment in not obtaining - the assistance of the telegraph in the working of the engines, and - the greatly increased consumption of coal consequent upon the - working the engines unnecessarily, because this evil is now nearly - removed; but some further reductions may still be made by using the - telegraph by night as well as day, which has not yet been in our - power to do, but which I trust will be commenced this week. - -The Committee to whom this report was made, and who had been also in -constant communication with Mr. Brunel, placed the result of their -investigation before the Board. The Directors, after carefully -considering the information given them, reported as follows:-- - - Your Directors, without pronouncing any judgment as to the ultimate - success of the Atmospheric System, and while they are prepared to - afford to the patentees and other parties interested in it the use - of their machinery for continuing their own experiments, have - arrived at the conclusion, with the entire concurrence and on the - recommendation of Mr. Brunel, that it is expedient for them to - suspend the use of the Atmospheric System until the same shall be - made efficient at the expense of the patentees and Mr. Samuda. - -At the meeting in August, the proprietors adopted the Directors' report, -and the line was worked throughout by locomotives on and after September -9. - -In the following November Mr. Thomas Gill, the chairman of the Board of -Directors, published an 'Address to the Proprietors,' in which he -strongly deprecated the abandonment of the Atmospheric System, and -proposed that the Company should embark on a further experiment. Mr. -Gill's pamphlet was referred to three of the Directors, Mr. Thomas -Woollcombe, Mr. Charles Russell, and Mr. James Wentworth Buller. With -Mr. Brunel's assistance, and to a great extent from memoranda written by -him, they prepared a statement which went very fully into all the points -raised by Mr. Gill. - -After combating Mr. Gill's propositions, they observe:-- - - Of the two men who are most deeply concerned in the further trial - of any reasonable experiment to perfect the Atmospheric System, we - find that one, Mr. Brunel, disapproves of the proposal for the - purpose as insufficient and unsatisfactory; the other, Mr. Samuda, - had not sufficient confidence in the result, or in Mr. Gill's - estimates for its accomplishment, to offer the only security which - would justify the Company in endeavouring to effect it. - -In conclusion they express an opinion that the suspension of the -Atmospheric System in the previous September was a prudent and necessary -step, and that nothing had since occurred to justify its resumption. - -The proprietors adopted the view taken by the Committee, and no further -attempt was made to work the railway on the Atmospheric System. - -Under these circumstances, it cannot be a matter of surprise that Mr. -Brunel was much censured for having advised the South Devon Railway -Company to work their line on the Atmospheric System. - -The reasons which led him to recommend the use of the Atmospheric System -on the South Devon, and the causes of its failure, have been very fully -described, and it has been also shown that the most important of these -were the defects of the pumping-engines, and the deterioration of the -longitudinal valve. - -When the formidable character of these difficulties had fully declared -itself, the South Devon Railway Company were not in a position to spend -any more money upon a system which, as the event had proved, was, in one -of its most important details, still in the experimental stage. - -There can be no doubt that the abandonment of the Atmospheric System was -the wisest step which, under the circumstances, could be adopted; and it -was recommended to the Directors by Mr. Brunel with a simple and -self-sacrificing disregard of every consideration except that which was -always paramount with him, the interests of those by whom he was -employed.[72] - - -NOTE (p. 143). - -_Comparison of Stationary and Locomotive Power._ - -In order clearly to set forth the reasons which justify the statement -made by Mr. Brunel,[73] that stationary power if freed from the weight -and friction of any medium of communication, such as a rope, must be -cheaper than locomotive power, it is desirable to consider, (1) the -waste of power which arises from the locomotive having to move itself as -well as the train; and (2) the excess of cost at which a given power was -supplied by a locomotive, as compared with that at which it could have -been supplied by a stationary engine. - -On the first point, the best information can be obtained from -experiments made by Mr. Daniel Gooch during the gauge controversy. The -results are very suitable for use in the present investigation, as the -South Devon was to be a broad-gauge railway. Moreover, as the -broad-gauge engine with which these experiments were tried was one of a -class more powerful for their weight not only than the contemporary -narrow-gauge engine, but also than the engines Mr. Brunel had experience -of when he wrote his report three years previously, the results may be -considered to represent very favourably the then existing case for the -locomotives. - -The engine employed in the experiments weighed, with its tender, about -fifty tons. The maximum power it was capable of delivering by the -pressure of steam in its cylinders was represented as a tractive force -of 4,900 lbs. at a speed of 60 miles an hour, equivalent to 784 -indicated horse-power; and at 40 miles an hour 5,200 lbs., equivalent to -555 indicated horse-power. - -It is next to be considered how this power would, when running at the -speeds mentioned, be employed in overcoming the elements of resistance. -These are:-- - -(1) The working friction of the machinery. - -(2) The rolling resistance of the engine and tender. - -(3) The air resistance due to the engine frontage. - -(4) The rolling resistance of the train. - -(5) The air resistance on the portion of the train unprotected by -the tender. - -(6) The resistance due to gradient. - -The following symbols and quantities may be conveniently made -use of to denote the various terms of the equation between force -and resistance. - -Total available tractive force in lbs. F - -Weight of engine and tender (superfluous load) in tons 50 - -Weight of train (useful load) in tons W - -The sum of the resistances of machinery, rolling resistance, -and air resistance of engine and tender R - -Rolling resistance of train in lbs. per ton K - -Gradient G - -Speed in miles per hour V - -Resistance of air (according to the received empirical formula) - - 1 - = --- (frontage area) x V^{2} - 400 - -Frontage area of train in square feet 63 - -Frontage area of portion of train unprotected by the tender, -in square feet 24 - -For a locomotive train therefore - 24 - F = R + WK + --- V^{2} + (50 + W) 2240 G. - 400 - -For a system that dispenses with the locomotive - - 63 - Tractive force = WK + --- V^{2} + W 2240 G. - 400 -Therefore - - W (K + 2240 G) + .1575 V^{2} - - = the useful tractive force, and - - R + 112000 G - .0975 V^{2} - - = the tractive force wasted by the use of the locomotive. - -Therefore - - F={R + 112000 G-.0975 V^{2}} + {W (K + 2240 G) +.1575 V^{2}} - -and the useful load - - (F- R - 112000 G - .06 V^{2}) - W = ----------------------------- - K + 2240 G. - - -The values which Mr. Gooch's experiments give for the two selected -speeds are as follows[74]:-- - - +---------------+---------+-----------------+----------+ - |Miles per Hour | R (lbs.)| K (lbs. per ton)| F (lbs.) | - +---------------+---------+-----------------+----------+ - | 40 | 1500 | 12.5 | 5200 | - | 60 | 2100 | 18.6 | 4900 | - +---------------+---------+-----------------+----------+ - -Using these values, the results in the following table are obtained, -being the conditions appropriate to the two speeds at successive -ascending gradients:-- - - +------+---------+-------+-------+------+-------+------+------+-----------+ - |Miles |Ascending|Useful |Super- | Gross|Useful |Waste |Gross |Ratio of | - |per |Gradient |Load | fluous| |Load |Horse-|Horse-|Horse-power| - |Hour | |in tons|Load in| |in tons| power| power|Waste to | - | | | | tons | | | | |Useful | - | | | | | | | | |Horse-power| - +------+---------+-------+-------+------+-------+------+------+-----------+ - | {| 0 | 288 | 50 | 338 | 411 | 144 | 555 | .35 | - | {| 1/200 | 128 | 50 | 178 | 352 | 203 | 555 | .58 | - | {| 1/100 | 71 | 50 | 121 | 292 | 263 | 555 | .90 | - | 40 {| 1/75 | 50 | 50 | 100 | 252 | 303 | 555 | 1.20 | - | {| 1/50 | 23.8 | 50 | 73.8| 173 | 382 | 555 | 2.21 | - | {| 1/40 | 11.7 | 50 | 61.7| 113 | 442 | 555 | 3.91 | - | {| 1/36.3 | 7 | 50 | 57 | 82 | 473 | 555 | 5.77 | - | | | | | | | | | | - | {| 0 | 139 | 50 | 189 | 504 | 280 | 784 | .56 | - | {| 1/200 | 68 | 50 | 118 | 415 | 369 | 784 | .89 | - | {| 1/100 | 35.7 | 50 | 85.7| 325 | 459 | 784 | 1.41 | - |60 {| 1/75 | 22.5 | 50 | 72.5| 265 | 519 | 784 | 1.96 | - | {| 1/52.3 | 7 | 50 | 57 | 160 | 624 | 784 | 3.90 | - +------+---------+-------+-------+------+-------+------+------+-----------+ - -Thus, on a level line, the engine, working up to 555 horse-power, could -just draw 288 tons of train at the rate of 40 miles per hour, wasting on -its own resistance only one-third of the power usefully employed on the -train; but when the speed was increased to 60 miles per hour, it could -not, though working up to 784 horse-power, draw more than 139 tons of -train, wasting on its own resistance more than half the power usefully -employed on the train. And again, at 40 miles per hour, though, as just -stated, it could draw on the level 288 tons, it could only draw 24 tons -of useful load at that speed up 1 in 50; while at 60 miles per hour, -though it could draw, as stated, 139 tons of train on the level, it -could only draw 23 tons of useful load up 1 in 75; and at the respective -speeds of 40 and 60 miles per hour, it could only take one carriage (7 -tons) up the respective gradients of 1 in 36, and 1 in 52. - -Hence to maintain a minimum speed of 40 miles per hour with locomotive -power on a line with long gradients of 1 in 40 involved on those parts -of the line a wasted power of nearly 4 times that usefully employed; and -if a minimum limit of 60 miles per hour were contemplated, a locomotive -of the most powerful class in existence three years subsequent to Mr. -Brunel's report advising the adoption of the Atmospheric System would -only have been able to take a single carriage up an incline of 1 in 52. -So heavily at high speeds on steep gradients is the performance of a -locomotive taxed by the resistance due to its own dead weight.[75] - - * * * * * - -A comparison has now to be made between the cost of power as developed -by a locomotive and as developed by a stationary engine. - -From the well-known experiments made for the information of the Gauge -Commissioners in December 1845, taking the high speed trials as the -basis of calculation, it appears that 4.5 lbs. of coke per horse-power -per hour may be taken as the average consumption of the engine.[76] - -It will be well, however, to allow for the improvement which was at the -time anticipated in locomotive working, and to assume an expenditure of -4 lbs. of coke per indicated horse-power per hour, as representing the -case then for the locomotive engine. - -Coke may be taken to have at that time cost 21_s._ a ton, or .0094_s._ -per lb. Moreover, a careful analysis of the Great Western Railway -half-yearly reports, for 1844 and 1845, shows that for every shilling -expended in coke, 1.44 shillings were expended on the average in wages, -oil and waste, repairs, etc. - -Putting the results together, it appears that for each single indicated -horse-power delivered by a high-speed locomotive, the cost per hour was -0.0915_s._ or 1.098_d._; that is to say, about 1-1/10_d._ per hour. - -Let this now be compared with the cost per horse-power per hour at which -the best Cornish pumping engines had long been known to perform the -work. This comparison is manifestly a rational one--with reference to -the kindred employment of engine power in atmospheric pumping-engines. - -The performances of nearly all the pumping-engines in Cornwall were for -many years so systematically and exactly reported, and the reports of -each were so critically scrutinised by the rival makers, that the data -they supply may be relied on without hesitation. It was well known that -the best of the engines continuously performed useful work with a -consumption of coal at the rate of 2.33 lbs. per delivered horse-power -per hour, or, counting coal at 16_s._ per ton (a fair price on the South -Devon), at the cost of .2_d._, or one-fifth of a penny per horse-power -per hour. - -But it was not in its consumption of fuel alone that stationary power -was the more economical; the expenditure in wages, oil, and tallow on -one of the pumping-engines above referred to, when doing 200 horse-power -of useful work, did not exceed 20_s._ for the twenty-four hours, or -one-twentieth of a penny per horse-power per hour, while the cost of -repairs was merely nominal. - -Thus if fuel, wages, oil, and tallow be brought into one item, it is -seen that the cost of one horse-power in stationary engines such as the -then existing Cornish engines was only .25_d._ per hour, or less than -one-fourth of its cost when developed by a locomotive, which has been -shown to have been 1.098_d._ per hour. - -[Illustration: PLATE III - -THE ROYAL ALBERT BRIDGE. - -H. Adlard. Sc.] - - - - -CHAPTER VII. - -_RAILWAY BRIDGES AND VIADUCTS._ - - 1. BRICKWORK AND MASONRY BRIDGES--HANWELL VIADUCT--MAIDENHEAD - BRIDGE--FLYING BRIDGES--LETTER FROM MR. BRUNEL ON BRIDGE - CONSTRUCTION (DECEMBER 30, 1854)--2. TIMBER BRIDGES--SONNING - BRIDGE--BATH BRIDGE--STONEHOUSE VIADUCT--BOURNE VIADUCT--ST. MARY'S - VIADUCT--VIADUCTS ON THE SOUTH DEVON RAILWAY--IVY-BRIDGE--VIADUCTS - ON THE SOUTH WALES RAILWAY--NEWPORT--LANDORE--VIADUCTS ON THE - CORNWALL RAILWAY--ST. PINNOCK--VIADUCTS ON THE WEST CORNWALL AND - TAVISTOCK RAILWAYS--PRESERVATION OF TIMBER--3. CAST-IRON - BRIDGES--LETTER ON USE OF CAST IRON (APRIL 18, 1849)--HANWELL - BRIDGE--EXPERIMENTS ON CAST-IRON GIRDERS--EXTRACT FROM LETTER TO - SECRETARY OF COMMISSION ON APPLICATION OF IRON TO RAILWAY - STRUCTURES (MARCH 13, 1848)--4. WROUGHT-IRON BRIDGES--GIRDER - BRIDGES--EXPERIMENTS ON WROUGHT-IRON GIRDER--OPENING - BRIDGES--TRUSSED BRIDGES--NEWPORT VIADUCT--WINDSOR BRIDGE--CHEPSTOW - BRIDGE--METHOD OF SINKING THE CYLINDERS--DESCRIPTION OF THE MAIN - TRUSS--THE FLOATING OPERATIONS--THE ROYAL ALBERT BRIDGE AT - SALTASH--THE CENTRE PIER--DESCRIPTION OF THE SUPERSTRUCTURE--THE - FLOATING AND RAISING OF THE TRUSSES--OPENING OF THE BRIDGE BY H. R. - H. THE PRINCE CONSORT--_NOTE_: EXPERIMENTS ON MATTERS CONNECTED - WITH BRIDGE CONSTRUCTION. - - -In Chapter IV. a general history has been given of the railways of which -Mr. Brunel was the engineer; but the bridges and viaducts designed by -him are so numerous and important that it has been thought advisable to -devote a separate chapter to their consideration. - -The bridges selected for mention have been grouped according to the -nature of the material used in their superstructure. This arrangement is -the most convenient one for giving a concise description of the most -remarkable of Mr. Brunel's bridges, and for stating the circumstances -which guided him in the determination of the particular form of -construction used in each case. - -The works are therefore divided into four groups, namely, brickwork and -masonry, timber, cast iron, and wrought iron.[77] - - -_Brickwork and Masonry Bridges._[78] - -The viaduct which carries the Great Western Railway over the valley of -the river Brent near Hanwell is the first of Mr. Brunel's important -railway works.[79] It is a handsome brickwork structure, 65 feet high, -with eight semi-elliptical arches, each 70 feet span and 17 feet 6 -inches rise. The spandrils of the arches are lightened by longitudinal -spandril-walls; the piers are also hollow, and the structure is -throughout made as light as possible. It is on this account interesting, -as showing the care taken by Mr. Brunel from the commencement of his -practice to distribute the material in the simplest and most effective -manner.[80] - -The great bridge over the Thames at Maidenhead contains two of the -flattest, and probably the largest arches that have yet been constructed -in brickwork. The river, which is about 290 feet wide, flows between low -banks; in the middle of the stream there is a small shoal, of which Mr. -Brunel took advantage in building the centre pier. - -It was originally intended that the foundation of the bridge should be -on the chalk, which was at a short distance below the surface; but it -was found to be very soft, and Mr. Brunel therefore decided to place the -foundations of the bridge on a hard gravel conglomerate overlying the -chalk. The main arches are semi-elliptical, each of 128 feet span and 24 -feet 3 inches rise. They are flanked at each end by four semicircular -arches, one of 21 feet span, and three of 28 feet span, intended to give -additional water-way during floods. The radius of curvature at the crown -of the large arches is 165 feet, and the horizontal thrust on the -brickwork at that point is about 10 tons per square foot. - -In the interior of the structure immediately landward of the large -arches, Mr. Brunel constructed flat arches loaded with concrete. The -centerings of these were struck, and an active thrust opposed to the -main arches before their centerings were eased.[81] The line of -pressure of each main arch was diverted downwards by the thrust of the -flat arch adjoining it without the necessity of employing a great mass -of brickwork in the abutment. - -The woodcut (fig. 1) shows the form of the main arches and the flat arch -referred to.[82] - -[Illustration: Fig. 1. Maidenhead Bridge. - -_Longitudinal Section._ - -_Scale of feet._] - -The Maidenhead bridge is remarkable not only for the boldness and -ingenuity of its design, but also for the gracefulness of its -appearance. If Mr. Brunel had erected this bridge at a later period, he -would probably have employed timber or iron; but it cannot be a matter -of regret that this part of the Thames, although subjected to the -dreaded invasion of a railway, has been crossed by a structure which -enhances the beauty of the scenery. - - * * * * * - -There are two other large brick bridges over the Thames, one at -Gathampton and another at Moulsford, that at Moulsford crossing the -river obliquely at an angle of 45 deg.. In each of these bridges there are -four arches, of 62 feet span on the square. - -Other good examples of brick bridges are the turnpike road bridge, 60 -feet high, with three arches, across the deep cutting at Sonning Hill, -and the bridge, with one opening of 60 feet and four side arches of 18 -feet span, over the river Kennet at Reading. - -The bridge over the Avon at Bathford, of 87 feet span, and the bridge -crossing the same river at Bath, with an arch of 88 feet span, are -handsome Bath-stone structures with semi-elliptical arches. Near Bristol -there is an ornamental bridge of masonry with three Gothic arches, the -centre arch having a span of 100 feet.[83] Another bridge of Gothic -design, with two arches of 56 feet span, carries the railway over the -Floating Harbour.[84] - - * * * * * - -The bridges which have hitherto been noticed are all on the Great -Western Railway. On the Bristol and Exeter Railway there is a large -stone bridge over the New Cut at Bristol, built in 1840, which has a -single segmental arch of 120 feet span, and 20 feet rise. Owing to some -imperfect workmanship in the interior masonry of the arch, and possibly -to some unequal yielding of the abutments, the crown sunk much more than -had been expected. - -On his later railways Mr. Brunel did not build large arches of brickwork -or masonry, though he constructed several lofty and extensive viaducts -of these materials with spans varying from 40 to 60 feet. - -Mr. Brunel seldom employed artificially piled foundations to support -masonry. When the ground was soft, he preferred to rely on a large -extent of bearing surface, and ensured uniformity of settlement by an -accurate distribution of the load. Several of his large viaducts and -bridges, standing on ground of a soft and spongy nature, were -constructed on this principle. - -A class of bridge of striking outline was used in the cuttings on the -Bristol and Exeter Railway, and on the other railways subsequently made. -Bridges of this class were called flying bridges. Instead of arches -resting on piers and abutments, the bridge has a single arch, reaching -from one side of the cutting to the other, and springing from the -slopes, which it helps in some measure to support. A flying bridge of -large dimensions near Weston-super-Mare carries a road across the -cutting at a height of 60 feet above the line of rails, with a clear -span of 110 feet. - -The quantity of masonry in these bridges is much less than in those of -the ordinary construction; and lofty and expensive centering is not -required, as the bridge can be built before the cutting is excavated to -its full dimensions. - -This class of bridge, by the avoidance of abutments and counterforts, -simplifies the construction of skew arches, while on sharp curves it -presents but little obstruction to the view along the line. - -A curious use of arches of this construction, as applied by Mr. Brunel, -may be seen on the South Wales Railway near Llansamlet, between Neath -and Swansea. A deep cutting through the coal measures showed a tendency -to slip, and a large amount of excavation would have been required to -flatten the slope, as a hill rose immediately above the side of the -cutting. Four of these flying arches were thrown across the cutting at -short intervals, and weighted with heavy copper slag, so that the sides -of the cutting are kept apart by the thrust of the loaded arches. - -Among the skew bridges on Mr. Brunel's railways, there are a few of -extreme obliquity. Of these may be mentioned two large road bridges near -Berkeley, over the Bristol and Gloucester Railway, one being 48 deg. and the -other 53 deg. off the square. Both the bridges are of brickwork, and in the -arch of the first one, which was set in Roman cement, hoop iron was -introduced in the manner successfully employed by Sir Isambard Brunel. -On the South Devon Railway, near Plympton, there is a skew bridge 63 deg. -off the square. - -On the Great Western Railway, in the neighbourhood of Bath and Bristol, -there are skew bridges of ashlar masonry built on the mechanically -correct principle of spiral tapering courses, the bed-joints in every -part of the arch being made at right angles to the lines of pressure. By -this method the arch does not depend for its stability on the friction -and cohesion of the materials, as it does to a great extent in very skew -bridges, built in the usual way with spiral parallel courses, especially -when the arches are semi-circular or semi-elliptical. - - * * * * * - -Mr. Brunel's bridges of masonry and brickwork were well known for the -comparatively small quantity of material used in them; and, though it -was requisite that the materials and workmanship should be of superior -quality, their cost was comparatively small. - -The specifications he prepared for all his works, and on which the -contracts were based, were noted for the completeness with which they -were drawn up, and for their not requiring a standard of perfection -higher than that which was actually to be carried out. The confidence -with which Mr. Brunel was regarded enabled him to insist with effect on -the work being executed according to his interpretation of the -contract. - -In connection with the design of engineering works, and especially of -brickwork and masonry bridges, the following letter from Mr. Brunel to -one of his assistants, who was abroad, will be found interesting:-- - - - December 30, 1854. - - Let me give you one general piece of advice--that while in all - works you endeavour to employ the materials used in the most - economical manner, and to avoid waste, yet always put rather an - excess of material in quantity. You cannot take too much pains in - making everything in equilibrio; that is to say, that all forces - should pass _exactly_ through the points of greater resistance, or - through the centres of any surfaces of resistance. Thus, in - anything resembling a column or strut, whether of iron, wood, or - masonry, take care that the surface of the base should be - proportioned that the strain should pass through the centre of it. - Consider all structures, and all bodies, and all materials of - foundations to be made of very elastic india-rubber, and proportion - them so that they will stand and keep their shape: you will by - those means diminish greatly the required thickness: _then add 50 - per cent_. So in trussed framework of wood or iron, experience - shows that you cannot refine too much upon the perfection of the - designing of every little detail by which all strains are carried - exactly through the centres of the rods or struts and the centres - of the bearing surfaces. And remember, always in retaining walls to - give plenty of batter; never build an upright wing-wall, or - retaining wall. To a man who has an instinctively mechanical - mind--and no other can be an engineer--the advice I have given you - above is all I need say; but this advice is the result of a good - deal of experience, purchased by failures of my own, and by looking - at those of others, and is, I assure you, valuable advice, to be - followed literally and strictly, and not to be considered as a mere - theoretical refinement, to be neglected in practice. Practically - too much attention cannot be paid to these precautions. I have - found that there is not a single substance we have to deal with, - from cast-iron to clay, which should not practically be treated - strictly as a yielding elastic substance, and that the amount of - the compression or tension, as the case may be, is by no means to - be neglected in practice any more than in theory. Bear in mind also - that which is too often neglected and involves serious - consequences, that masonry or brickwork has not half the strength - which is generally calculated upon until the mortar is hard, and - that you cannot keep centres or shores up too long. - - -_Timber Bridges and Viaducts._ - -Mr. Brunel's timber bridges and viaducts are remarkable on account of -the extensive scale on which he employed that material, and the simple -and efficient type of construction which he adopted in the largest -structure as well as in the smallest. - -In 1841 Mr. Brunel constructed a timber bridge of five spans to carry a -public road over the Sonning cutting of the Great Western Railway, a -short distance east of Reading. The total width of the space across -which the road had to be carried was 240 feet. The superstructure rests -on four tall frameworks or trestles of timber forming the piers. Two of -these piers are on either side of the railway, and the others are about -halfway up each slope. - -The road rests on a platform of timber planking, carried on three -longitudinal beams, which are supported at nearly equal distances by -timber struts radiating from points on the piers about 12 feet below the -level of the carriage road. The system of arrangement of these struts -will be best understood by a reference to the woodcut given below (fig. -5, p. 187) of one of the Cornwall viaducts, of which the Sonning bridge -may be regarded as in some measure the prototype.[85] - - * * * * * - -The skew timber bridge on the Great Western Railway near the Bath -Station, carrying the line over the river Avon, was constructed about -the same time as the Sonning bridge. It has two spans of 36 feet each on -the square, but the obliquity is so great that the span on the skew is -89 feet. Each opening has six laminated arched ribs parallel to the line -of the railway. These support the platform of the bridge, and are built -up in five layers of curved Memel timber, six inches thick, bolted -together. The thrust is counteracted by iron ties connecting the ends of -the ribs. The inner spandrils are filled in by cross-ties and braces, -and those of the outer ribs by ornamental cast ironwork. - - * * * * * - -The two bridges already described are almost the only timber bridges of -importance on the main line of the Great Western Railway from London to -Bristol. Shortly after the completion of this railway Mr. Brunel began -to make an extensive use of timber in his designs, and in so doing took -full advantage of the largeness of the material, in order to avoid -intricacy of construction. - -A well-known arrangement for forming beams of greater strength than -could be obtained by single pieces of timber was adopted by Mr. Brunel -after a careful investigation of its merits. This arrangement consists -in joining together two beams of timber placed one above the other, by -means of bolts and joggles, so as to form a beam nearly equivalent in -strength to a single piece of timber of the same depth as the two pieces -united.[86] By this plan, the length which could be spanned by simple -beams, without the introduction of trussed framework, was nearly -doubled. - -The distance between the piers of railway bridges is generally too great -to allow of the superstructure being constructed of simple beams, and in -such cases Mr. Brunel adopted forms of framing similar in the -arrangement of their parts to the common designs of king and queen -trusses employed in roofs. - - * * * * * - -One of Mr. Brunel's early timber viaducts was that erected in 1842 at -Stonehouse, on the Bristol and Gloucester Railway. It consisted of a -series of five openings of queen trusses 50 feet span, resting on piers -formed of timber trestles. - -[Illustration: QUEEN TRUSS.] - -[Illustration: KING TRUSS.] - -In the Bourne viaduct, across the Stroudwater Canal, on the Cheltenham -and Great Western Union Railway, there was a span of 66 feet, with three -timber trusses, for the two lines of way. Each of these trusses may be -described as a king truss with an internal queen truss. The inclined -timbers or principals rested in iron shoes upon the piers, and were -connected together by bolts and joggles. - -The upper horizontal or collar beam of the queen truss carried the -roadway planking, which was continued upon beams supported by the -principals. The timbers carrying the roadway received support from -struts radiating from the feet of the queen posts, which were connected -with the apex of the king truss by iron ties. The horizontal tie bars -were of wrought iron. The arrangement of the truss is shown in the -woodcut (fig. 2). - -[Illustration: Fig. 2. Bourne Viaduct. - -_Scale of feet._] - -The side openings consisted of four spans of 30 feet, with trusses of -the Stonehouse viaduct type, of one span of 25 feet and ten spans of 20 -feet, with double beams. - -The St. Mary's viaduct, across the canal in the Stroud Valley, was -constructed with one span of 74 feet, with trusses similar to those at -the Bourne viaduct.[87] - -In the year 1846 Mr. Brunel made an elaborate series of experiments on -the strength of large timber. Some account of these is given in the note -to this chapter. - -Fortified by the information thus obtained, he was able to proceed with -confidence to an extensive use of timber in the viaducts of the South -Devon, the Cornwall, and other railways. - -Between Totness and Plympton, the South Devon Railway, running along the -skirts of Dartmoor, crosses four deep valleys, by lofty viaducts, all of -the same design. - -Three of them can be seen at one time, and they form striking and -elegant features in the landscape. - -The viaduct at Ivybridge is the highest of these. It is on a curve, and -has eleven openings of 61 feet each; the extreme height is 104 feet. - -[Illustration: Fig. 3. Ivybridge Viaduct. - -_Scale of feet._] - -The piers are of masonry, each consisting of two slender and slightly -tapered shafts about 7 feet square, rising to the level of the rails. -The superstructure was originally designed for a railway on the -Atmospheric System, and was therefore only intended to bear the load of -a train of carriages. The framework was placed below the level of the -rails, and, as will be seen in the woodcut (fig. 3), it consists of a -polygonal frame, with a few subsidiary struts, the feet of the main -timbers being tied together by wrought-iron rods. There are two of these -frames, one at each side of the bridge, to support the planking of the -roadway. Before the construction of the viaducts was proceeded with, a -complete span of the superstructure, consisting of a pair of the frames -with the planking, was erected at Bristol, and tested to ascertain the -efficiency of every part. - -When it became necessary to strengthen the superstructure to enable it -to carry the weight of locomotives, a strongly trussed parapet was added -above the trusses, as shown in the woodcut. After the lapse of twenty -years, the timber having begun to decay, wrought-iron girders have been -inserted, which rest on the stone piers; the framing, however, has not -been removed. - - * * * * * - -Shortly after the completion of the viaducts on the South Devon Railway, -those on the South Wales Railway were constructed. The most important on -this line are those at Landore and Newport. - -The viaduct at Landore, near Swansea, is 1,760 feet long, as the railway -here crosses a wide valley. It has 37 openings, and there are a variety -of spans, one of 100 feet, two of 73 feet, two of 64 feet, two of 50 -feet, and the rest of about 40 feet each. Most of these consist of a -superstructure of queen trusses. The piers are of different materials, -some being almost entirely of masonry, some partly of masonry and partly -of timber, and others entirely of timber, according to the nature of the -foundation.[88] The chief feature is the centre span, with an opening -of 100 feet, the superstructure of which is a very fine piece of -timber-work.[89] It has four trusses, one on either side of the two -lines of rails, of the form shown in the woodcut (fig. 4). The truss -consists of a four-sided frame placed within a five-sided frame, the -angles of each polygon being connected by bolts and struts with the -middle of the sides of the other polygon. - -[Illustration: Fig. 4. Landore Viaduct. - -_Scale of feet._] - -The planking of the roadway rests on double beams, supported at several -points in the manner shown in the woodcut, each point having -suspension-rods to connect it with the nearest angles of the frames. The -arrangement of the double polygonal frame and of the tie-rods enables -the transverse strength of the timbers to exercise considerable -resistance to any distortion of the shape of the truss by a rolling -load. To prevent any tendency of the top of the frame to yield sideways -under the compressive strain, the tops of the trusses are connected by -transverse struts or braces, the two outside trusses being steadied by -raking ties attached to outriggers projecting from below the flooring of -the bridge. The thrust of the polygonal frames is resisted by -wrought-iron tie-bars at the level of the roadway beams. All the -tie-rods in this bridge are double, with one bar on each side of the -timbers, to avoid the necessity of making large bolt-holes.[90] - -The viaduct at Newport consists of eleven spans with queen trusses, -resting on piles. The main span, over the river Usk, is 100 feet, and -was constructed with timber trusses very similar to those at Landore. -Shortly before it was finished, the viaduct was burnt down. In -rebuilding it, wrought-iron trusses were employed for the main span. - - * * * * * - -The works of the Cornwall Railway were commenced in the year 1852. The -district through which the line passes is very deficient in the -materials requisite for the construction of a railway. The granite of -the country is for the most part only applicable for ashlar; and the -slate, which is flat-bedded and so far fit for rubble masonry, is -frequently inferior in quality. - -In consequence of the number of valleys that the railway had to cross, -the aggregate length of the viaducts, thirty-four in number, exclusive -of the Saltash bridge, is upwards of four miles on a line of sixty -miles. By the use of timber, a great saving was effected in the first -cost of the works; and though it is a material which in time requires -renewal, its use on the Cornwall Railway enabled the line to be made -with the capital at the command of the Company; while, allowing for the -cost of subsequent repairs, the total expenditure did not differ much -from what it would have been had the superstructure of the viaducts been -of more durable materials. The comparatively small cost of these -structures enables them to be, in certain places, economically -substituted for embankments, as was done on the Cornwall Railway. - -The viaducts are to be found over the whole length of the line, but they -are most frequent between the Liskeard and Bodmin Road stations, where -the railway crosses numerous branches of the Glynn valley. - -Most of these viaducts are of one type of construction. - -The piers are formed of plain walls, built up to thirty-five feet below -the level of the rails, those of the more lofty viaducts being -strengthened by buttresses. In the woodcut (fig. 5) is shown a portion -of the St. Pinnock viaduct, from which the form of these piers will be -understood. - -This viaduct is the loftiest on the Cornwall Railway, the rails being at -a height of 153 feet above the ground. A description of the -superstructure will serve to explain the design of the principal -viaducts on the line. - -The roadway planking rests on three beams, which run longitudinally -throughout the whole length of the viaduct. Each of these beams consists -of two pieces of timber, one above the other, fastened together by bolts -and joggles. The piers are 66 feet apart, centre to centre, and the -longitudinal beams are supported, at four nearly equidistant points in -this space, by straight single timbers radiating from the tops of the -piers. The feet of the timbers, which rest on the masonry in cast-iron -shoes, are connected together by wrought-iron tie-bars; and the -framework is made rigid by iron diagonals. - -[Illustration: _Scale of Feet_ _Transverse section_ - -_Plan of base of pier._ _Plan of top of pier._ - -Fig. 5. St. Pinnock Viaduct.] - -It will be observed in the transverse section (fig. 5) that the whole -weight of the superstructure is concentrated immediately over those -points in the piers where the three buttresses meet. The diagonal braces -which are attached to each set of the main timbers give transverse -stability to the superstructure.[91] - -It was desirable, both in first construction and in subsequent repairs, -to have a uniform dimension for the spans, and the subdivision of 66 -feet was determined on as being suitable for the economic construction -of the greater part of the work. The subdivision of this length was such -as to allow of single whole timbers being sufficient for the direct -supports of the longitudinal beams; and as these beams were supported at -intervals of 15 to 20 feet, no intermediate trussing was required. As -the inclined timbers met the tops of the piers at a moderate -inclination, the outward thrust caused by unequal loading of the spans -of the viaduct was inconsiderable, and was easily counteracted by light -iron ties. - -The stone for the piers was for the most part procured in the -neighbourhood, the design of the masonry being such as to enable stone -of the country to be used; and, as the timber superstructure was built -in pieces of moderate size,[92] and easily obtained, the expenditure was -probably not far from the minimum under the existing conditions.[93] - -On the South Devon and Tavistock Railway, the viaducts are six in -number, and from 62 to 132 feet in height. In these the piers were made -of a somewhat simpler form than those just described. At the lofty -viaducts, the buttresses were made with a uniform batter throughout -their height. The Walkham viaduct, near Tavistock, 132 feet high, with -fifteen openings of 66 feet span each, may be considered to exhibit the -most matured design of Mr. Brunel's timber viaducts. - -On the West Cornwall Railway a type of viaduct similar to that described -above was adopted; but as the general height was not so great, the spans -were 50 feet each, and the longitudinal beams were supported at three -points in each span, instead of at four as on the Cornwall Railway. In -consequence of the nature of the foundations, the piers of the nine -viaducts on this line were for the most part formed of upright timbers -well braced together, standing upon masonry footings. The viaduct at -Angarrack, 98 feet high, with 16 spans, which was constructed in 1851, -was remarkable for its light appearance, owing to the small number of -timbers in the superstructure and piers. - -Mr. Brunel paid great attention to the preservation of the material of -the timber bridges and viaducts. As early as 1835 he had been in -communication with Mr. Faraday as to the best method of testing the -extent to which the Kyanising solution penetrated into wood. Mr. Brunel -made a careful trial of all the different methods of preserving timber, -and employed the more successful of them on a very considerable scale. -He was so impressed with the importance of the preserving processes -being properly applied, that he on several occasions preferred to keep -the operation of preserving the timber in the hands of the Company, in -order that it might be done thoroughly, and under his own supervision. -He also minutely attended to the details by which timber structures may -be protected from decaying influences. - - -_Cast-Iron Bridges_. - -Mr. Brunel did not make an extensive use of cast iron for the -superstructure of bridges. His views as to the employment of this -material in girders are clearly expressed in the following extract from -a letter to one of the Directors of the Great Western Railway:-- - - April 18, 1849. - - Cast-iron girder bridges are always giving trouble--from such cases - as the Chester Bridge, and our Great Western road bridge at - Hanwell, which, since 1838, has always been under repair, and has - cost its first cost three times over, down to petty little ones, - which, either in frosty weather or from other causes, are - frequently failing. I never use cast iron if I can help it; but, in - some cases it is necessary, and to meet these I have had girders - cast of a particular mixture of iron carefully attended to, and I - have taught them at the Bridgewater foundry to cast them with the - flange downwards instead of sideways. By these means, and having - somebody always there, I ensure better castings, and have much - lighter girders than I should otherwise be obliged to have. The - number I have is but few, because, as I before said, I dislike - them, and I pay a price somewhat above ordinary castings, believing - it to be economy to do so. - - I won't trust a bridge of castings run in the ordinary way, and at - foundries where I have not a person always watching; and, even if I - did, the weight requisite in a beam of ordinary metal and mode of - running would more than make up for the reduced price. - -The bridge at Hanwell referred to in this letter was one on the main -line of the Great Western Railway, over the Uxbridge road. In 1847 the -planking caught fire, and the cast-iron girders were destroyed by the -heat. - -The researches of Mr. Eaton Hodgkinson had drawn attention to the -importance of a proper proportionment of the top and bottom flanges of -cast-iron girders, and Mr. Brunel now made some experiments on this -point. As part of this investigation, eight girders, 30 feet long and 16 -inches deep, were tested by weights until they gave way. The -comparative areas of the top and bottom flanges were varied until a -correct proportion between the two was arrived at. The general result of -these large-scale experiments showed a lower breaking-weight than that -deduced from Mr. Hodgkinson's formula. - -When Mr. Brunel afterwards had occasion to use cast-iron girders, which -was chiefly for road bridges over railways, they were made of the form -which his experiments had shown to be the best;[94] but he repaired the -Hanwell Bridge with wrought iron. - -At about the same time the necessity for spanning wide openings had led -to larger girders being required than could be manufactured in single -castings, and Mr. Brunel had a large cast-iron girder made, 46 feet long -and 4 feet deep, of five pieces bolted and keyed together. It was tested -until it gave way with a load of 92 tons on the middle. The result -showed that the several parts had been well connected, and that the -strength of the beam was not much less than the calculated strength of a -beam of the same size in a single piece. Mr. Brunel did not, however, -use girders of this construction, as the rapid introduction of wrought -iron rendered it unnecessary. - -Cast iron was introduced, though not for girders, in many of the brick -and stone bridges on the Great Western Railway. It was used in the form -of troughs sunk into the crown of the arch in bridges where the headway -was very limited. The rails were laid along the bottom of the trough -within a few inches of the soffit or underside of the arch. - -Although, after the careful experiments and investigations he had made, -and the experience he had obtained, Mr. Brunel did not make use of cast -iron for large girders, he looked forward to the possibility of such -improvements being introduced into the manufacture as would enable sound -castings of considerable size to be made of homogeneous material. - -He expressed this opinion in a letter to the Secretary of the Commission -on the Application of Iron to Railway Structures. This Commission (which -Mr. Brunel called 'The Commission for stopping further improvements in -bridge building') was appointed 'for the purpose of inquiring into the -conditions to be observed by engineers in the application of iron in -structures exposed to violent concussions and vibration.' Mr. Brunel, in -common with most engineers, thought it would be very inexpedient that -any _regles de l'art_ should be laid down, and took up the cudgels -boldly on behalf of the liberty of the profession:-- - - March 13, 1848. - - At present cast iron is looked upon, to a certain extent, as a - friable, treacherous, and uncertain material; castings of a limited - size only can be safely depended upon; wrought iron is considered - comparatively trustworthy, and by riveting, or welding, there is no - limit to the size of the parts to be used. Yet, who will venture to - say, if the direction of improvement is left free, that means may - not be found of ensuring sound castings of almost any form, and of - twenty or thirty tons weight, and of a perfectly homogeneous - mixture of the best metal? Who will say that beams of great size of - such a material, either in single pieces or built, may not prove - stronger, safer, less exposed to change of texture or to injury - from vibration, than wrought-iron, which in large masses cannot be - so homogeneous as a fused mass may be made and which when welded is - liable to sudden fracture at the welds?[95] - - -_Wrought-Iron Bridges._ - -Notwithstanding the cost of wrought iron, but a short time elapsed -between its introduction into bridge building and its use in structures -of great magnitude. Mr. Brunel had been long familiar with the -application of riveted wrought-iron work, and he was the first to -encourage its use on a large scale in shipbuilding by recommending its -adoption in the 'Great Britain' steam-ship in 1838. - - -_Girder Bridges._ - -The strains on girders made of homogeneous material have been carefully -and ably calculated by mathematicians; and the investigations thus made -have directed inquiry into the right channels for determining the nature -of the stresses on the several parts of the built-up structures now so -much in use. Principles have by degrees been laid down, and lines of -thought have been suggested and followed out which were unknown at the -time when wrought-iron girders were first introduced in the construction -of railway bridges.[96] - - * * * * * - -[Illustration: _Scale of feet_. - -Fig. 6. Experimental Girder. - -_Transverse Section_.] - -Shortly after Mr. Brunel began to use wrought iron for bridge girders, -he made an experiment in order to determine the weak points of a large -wrought-iron plate-girder. Mr. Edwin Clark, in his work on the -'Britannia and Conway Tubular Bridges,' vol. i. p. 437, gives a -description of what he justly terms 'this magnificent experiment.' The -girder was of the section shown in the woodcut (fig. 6), 70 feet in -length, and of 1/4-inch plate throughout. It was weighted gradually, and -gave way with a load of 165 tons on the centre, by the tearing apart of -the vertical web plate near the ends of the girder. When this portion -had been strengthened, and the girder again loaded, it gave way with a -load of 188 tons by the simultaneous failure of the top and bottom -flanges, that is to say, of the plates forming the triangles shown in -the woodcut.[97] - -The superior tensile strength of wrought iron to that of cast iron, and -the facility with which pieces could be joined together by riveting, -enabled girders of great size to be made. The thin wrought-iron plates -were arranged so as to form the top and bottom flanges of the girders as -well as the upright web connecting them. The metal in the top of a -girder being in compression, it was important so to dispose it that it -should resist the tendency to yield sideways under the strain. This -requirement was met in the experimental girder by the triangular section -of the top flange; and the convenience of this form for joining together -a number of plates, without difficulty or the use of long rivets, led -Mr. Brunel to use the triangular section also for the bottom flange. - -[Illustration: _Scale of feet._ - -Fig 7. Girder on South Wales Railway, 70 feet span. - -_Transverse Section._] - -Subsequent improvements in the facilities for bending wrought-iron -plates enabled him to use a form of cross section of wrought-iron -girder, the top flange of which was a nearly circular tube, the best -shape of strut to resist longitudinal compression. It is shown in the -woodcut (fig. 7), and was used in many of his bridges. - -This form was afterwards modified to that shown in fig. 8. The -semicircular top plate is stiffened by occasional cross diaphragms, and -while it was a good form to resist compression, it was more easily -painted than the closed-in top flanges shown in figs. 6 and 7. - -The forms of wrought-iron girder already referred to are those known as -plate girders, with continuous webs made of plates riveted together, and -therefore analogous to the beams of cast iron which they almost entirely -superseded. On Mr. Brunel's railways there are a great number of bridges -of these forms of girder, where the spans do not exceed 100 feet. For -larger spans he used wrought iron, in large and deep trussed frames, by -which means a great degree of economy was attained in the employment of -the material. - -[Illustration: _Scale of feet._ - -Fig. 8. Girder on Eastern Bengal Railway, 92 feet span. - -_Transverse Section._] - -The care which he had taken to satisfy himself of the action of the -strains in plate girders was of service in all the greater structures he -designed, as in all of them he employed wrought-iron girders to carry -the roadway, of a type somewhat similar to those already described, the -girders being supported at frequent intervals by the main framework or -truss. - - -_Opening Bridges._ - -The first large opening bridge which Mr. Brunel constructed was a -roadway swing bridge, 12 feet wide, across the new lock at the Bristol -Docks. The length of the overhanging end is 88 feet, and the other, or -tail end, which is 34 feet long, rests upon two wheels, which travel on -a circular rail. The weight of the overhanging end is rather more than -counterbalanced by large blocks of cast iron, forming part of the -pavement of the tail end. Almost the whole weight is borne on a centre -pivot, assisted by four wheels in fixed bearings, upon which runs an -inverted circular rail attached to the underside of the bridge. On the -pivot, which rests on a large cast-iron bed-plate, are two discs, one of -steel and the other of brass, which can readily be lubricated, or taken -out and renewed. - -[Illustration: _Scale of feet._ - -Fig. 9. Cumberland Basin Swing Bridge.] - -On the sides of the bridge are longitudinal wrought-iron plate-girders. -The top flange is pear-shaped, and the bottom flange triangular, having -three curved plates. The flanges are connected together by a vertical -plate web of wrought iron. The section is shown on the woodcut (fig. 9). -It admits of very simple riveting, without the use of angle irons. The -form of the bottom flange is suited to the compressive strain it has to -bear when the bridge is being moved. The top flange has also -wrought-iron tie-bars within the tube. When the bridge is across the -lock and open for traffic, the overhanging end rests on cams, which are -tightened up so as to lift and support the ends of the girders. As the -bridge rests almost entirely on a pivot of small diameter, it turns with -great ease. - -Near Gloucester there are two skew swing bridges somewhat similar to -each other in arrangement. Almost all the weight while turning is -supported on the piston of a hydraulic press, and the bridge therefore -turns round on the water in the cylinder. The first bridge is on the -main line of railway leading to South Wales, across a branch of the -River Severn, and is for two lines of way. It has three girders, 125 -feet long, of the form shown in fig. 7 (p. 194). The water pivot is in -the middle of the length of the bridge, which spans two openings of 50 -feet on the square. Before being turned the bridge was intended to be -lifted slightly off its bearings by the hydraulic press, and steadied by -four wheels, on which a portion of the weight was to be made to rest by -long springs within the girders, the range of which was to be limited in -one direction by a fixed stop. The central pier consists of five -cylinders of cast iron, each 6 feet in diameter, filled with concrete, -surmounted by a cast-iron ring or roller path. The railway company was -obliged to make this an opening bridge in order to provide for the free -navigation of the river should the old stone bridge lower down be -altered. This has not been done, and the railway swing bridge, -constructed in 1851, has not yet been opened. - -The other swing bridge at Gloucester is on the Dock branch, for one line -of way, with an opening of 50 feet on the square, the overhanging length -of the girders being 70 feet. While raised from its bearing and turning -on its water pivot it is steadied by two tail wheels, like the bridge at -the Bristol Docks. - -On the Bullo Pill branch of the South Wales Railway there is a small -wrought-iron drawbridge, for one line of way, of 30 feet span. It is a -lifting bridge on the _bascule_ principle, like many bridges over canals -in this country and in Holland. The opening part turns on a horizontal -axle, and is lifted by rods attached to the ends of two large beams or -levers, turning vertically, which are supported above the railway on a -timber framework. At the other ends of these beams is a counterbalance -weight. The bridge is opened or shut by pulling down either end of the -beams with a small chain. - -The other bridges are on the main line of the South Wales Railway, and -are four in number, each for two lines of way. - -One at Loughor is a wrought-iron swing bridge, of 30 feet opening, of -the ordinary construction, with girders 90 feet in length, resting upon -36 rollers, which are secured in a ring concentric with the pivot. The -opening and closing is effected by means of a crab, fixed clear of the -bridge, near the centre. A chain passes from the overhanging end of the -bridge to this crab, and taking one or two turns round the barrel, to -ensure a sufficient amount of friction, is led to the tail end. The -bridge can thus be opened or shut by turning the crab handle in opposite -directions. The overhanging end, when across the river, is raised -upwards to a small extent by weighted levers, and wedges are then drawn -in under it to give it a solid bearing. - -At Kidwelly and at Haverfordwest there are wrought-iron lifting bridges, -the former of 20 feet, and the latter of 30 feet span. Each of these -turns on a horizontal axle like the Bullo Pill bridge; but, instead of -being lifted by levers overhead, it has a narrow, heavily-weighted tail -end, beneath the planking of the viaduct, which is pulled down with a -chain worked by a crab. The portion which carries each line of way is -made to open independently. In this form of bridge no wedges or -adjusting arrangements are required for the bearings of the overhanging -end. - -Over the river at Caermarthen is a skew bridge of three girders, each -116 feet long, for a double line of way. It occupies two spans and rolls -back, so as to leave a 50-feet opening for the navigation. The swing -bridge at Bristol, already described, was at first intended to be a -rolling bridge, and to be furnished with wheels to run back on fixed -rails, but the difficulty of forming a good foundation for the wheel -path led to the design being altered. At Caermarthen the same difficulty -was overcome by putting wheels turning in fixed bearings on the pier and -abutment of the bridge. The undersides of the girders carry inverted -rails, and run back on the wheels. The bridge, when shut, is on an -incline of 1 in 50. When about to be opened it is made to assume a -horizontal position by turning a supporting cam to lower the overhanging -end, and the tail end then rises sufficiently to pass clear above the -part of the railway over which it runs back. - -By this arrangement the bridge, while in motion, moves along a level -path. It is opened and closed by hydraulic machinery. - -All these opening bridges have worked satisfactorily since they were -constructed. - - -_Trussed Bridges._ - -When the timber viaduct over the river Usk, at Newport, was burnt -down,[98] Mr. Brunel decided to form the new superstructure of the -centre opening with three iron trusses, for the two lines of way. - -These are bow and string girders, of 100 feet span, and were made of -considerable height, not only to reduce the strain on each of the -members of the framework, but also in order that the rib or upper -portion of each truss might be braced diagonally to the corresponding -portion of the other trusses, and headway left for the locomotive -chimneys to pass underneath. This bracing counteracts any tendency of -the ribs to bend sideways under the compressive strain. The form of the -trusses is shown in fig. 1, Pl. IV. (p. 206). Each truss is a -wrought-iron polygonal arch of triangular section, from which is -suspended a horizontal girder supporting the roadway. This girder also -forms the tie which connects the feet of the arch and counteracts its -thrust. The diagonal braces shown on the elevation of the bridge prevent -the arch from being distorted by the unequal loading caused by a -passing train. The middle truss is twice the strength of each of those -at the outside, being made so by increasing the thickness of the plates. -One of the outside trusses was tested with a distributed load of 1-1/2 tons -per foot-run of its length. - -[Illustration: _Scale of feet._ - -Fig. 10. Truss of Windsor Bridge. - -_Transverse Section._] - -At about the same time that the Newport viaduct was reconstructed, Mr. -Brunel designed the bridge over the Thames on the Windsor branch of the -Great Western Railway. This is a very large example of the bow and -string girder, the span being 202 feet, and the height of the truss 23 -feet. The trusses are three in number, for two lines of way, the middle -one being twice the strength of the outside trusses. The elevation of -the Windsor bridge is shown in fig. 2, Pl. IV. (p. 206). The bridge is -oblique to the river, being 20 deg. off the square. To steady the arched -ribs sideways a system of diagonal bracing extends over the whole of the -top of the trusses, except at the ends, where headway has to be left for -the trains. - -A section of the arched ribs and of the roadway girders in the centre of -one of the trusses is given in the woodcut (fig. 10). The arched rib, to -resist compression, is of triangular section.[99] - - * * * * * - -The borings to ascertain the nature of the ground at the foundations of -the piers were made in 1846, but it was not until 1848 that the works -were commenced. Each abutment consists of six cast-iron cylinders, 6 -feet diameter, which were sunk by excavating the gravel from their -interior by hand dredging and by placing weights on the top so as to -force them down. - -When each cylinder had been by this means sunk low enough to ensure a -good foundation, it was filled with concrete in the following manner. A -mixture formed of Thames ballast and Portland cement, in the proportions -of 8 to 1, was put into a canvas bag; this was lowered inside the -cylinder to the bottom, and, by pulling a rope, the mouth of the bag was -opened, and the concrete deposited under water in the bottom of the -cylinder. Whenever the work was interrupted, great care was taken before -recommencing it to clean off any deposit, in order that the new concrete -might adhere well to the old. When the cylinder had been filled to such -a height that there was no danger of its floating up when emptied, the -water was pumped out. The inside was then filled with concrete in the -ordinary manner. On the top were placed oak platforms, which support the -trusses of the bridge. - -One of the outside trusses was tested at Bristol in July 1849, by -loading it gradually with iron rails, beginning from one end, until the -whole truss was uniformly weighted with 270 tons, or 1-1/2 tons per -foot-run, observations on the deflection of different points of the -bottom girder being made both during the loading and unloading. The -results of this test were perfectly satisfactory. - -The superstructure of the bridge was erected on scaffolding, and the -line was opened on October 8, 1849. - - * * * * * - -It will be desirable here to notice one or two important features in -this as in almost all Mr. Brunel's bridges. - -The ordinary permanent way was laid over the bridges with ballast of -sufficient thickness to enable the road to be kept in repair in the same -manner as the other parts of the line. As there was no change in the -nature of the support given to the rails, no concussion was caused on a -train entering or leaving a bridge. The ballast took off from the -structure the vibration of the train; and, in the event of carriages or -even engines getting off the line, it helped in a great measure to -prevent their ploughing through the flooring. Where the flooring was of -timber the ballast protected it from fire. Also in long bridges there -was no necessity for any contrivance of sliding rails to allow for the -effects on the structure of changes of temperature. On the other hand, -the ballast added to the weight on the bridge. With the timber viaducts -this was an advantage, since it kept the various parts of the framework -in close contact, and prevented sudden jars being brought on them by the -rapidly applied load of a passing train. Even on the large bridges the -cost of the extra material requisite to support the weight of the -ballast was more than compensated for by the advantages above referred -to. - -Mr. Brunel employed timber flooring, as being the safest in the case of -carriages getting off the line, and also as being the cheapest. This -flooring in the iron bridges was generally laid diagonally on -wrought-iron cross girders, which were placed not at right angles to the -line, but obliquely, in order that the two wheels of the same axle of an -engine or heavy waggon might be on different cross girders at the same -time. By this arrangement the cross girders could be made of less -strength, and a saving effected in their cost and weight. - -The bridge over the Wye at Chepstow, and the Royal Albert Bridge over -the Tamar at Saltash, are the largest and most important of Mr. Brunel's -bridges. - -They are remarkable not only for their dimensions, but also for the -economical character of the designs, the form of their superstructures, -and the methods by which the foundations of the piers were made. - -At the part of the river Wye where it is crossed by the Chepstow Bridge, -a cliff of limestone rock rises on the left bank to a height of 120 feet -above the bed of the river, forming the precipitous edge of a broad -table-land; while on the right bank the ground slopes gently for a -considerable distance, rising only a little above high water, and is -composed partly of clay and partly of loose shingle interspersed with -large boulder stones. As it was necessary to leave a clear headway of 50 -feet above high water for the navigation, the line on one side of the -river is on an embankment of great height, and on the other side it -penetrates the cliff about 20 feet below the top. The whole space to be -bridged over, 600 feet wide, was divided into a river span of 300 feet, -and three land spans of 100 feet each (see fig. 3, Pl. V. p. 206.) At -one end of the great span a secure abutment was offered by the cliff of -limestone rock; but at the other end, and under the piers of the smaller -spans, the ground throughout was soft, and full of water. There was, -however, rock at a depth of 30 feet below the bed of the river. - -To reach this foundation with masonry, by means of a coffer dam, was -almost impracticable, as it was 84 feet below high water. - -The plan of building a stone pier on a foundation of piles was -considered, and abandoned on account of the expense. - -The method of sinking the cast-iron cylinders of the Windsor bridge has -been already described. The pneumatic process of sinking cylinders had -been introduced with great success at the Rochester bridge. - -In this process the cylinder is closed at the top and air forced in by -pumps until the water is expelled at the bottom. Workmen in the interior -excavate the ground and remove any obstacles which prevent the cylinder -from sinking, weights being added to force it down. As the air within is -at high pressure, the workmen enter, and the materials are passed in and -out, through an intermediate chamber, called an 'air lock,' fitted with -air-tight doors. The pneumatic method was ultimately employed at -Chepstow, to assist in sinking the cylinders. - -Before he decided on the plan for the foundations, Mr. Brunel had an -experimental cylinder made of cast iron, 3 feet in diameter, at the -bottom of which was an exterior screw flange 12 inches broad, and 7 -inches pitch, making one complete turn. This screw cylinder penetrated -the ground like an ordinary screw pile. In one instance it was rapidly -sunk to a depth of 58 feet, through stiff clay and sand, in 142 -revolutions;[100] yet, on another trial, when boulders were encountered, -there did not appear to be sufficient penetrating power. In one of these -trials, the screw, having got into a bed of running sand, had no hold, -and failed to descend. Mr. Brunel then had the cylinder partly raised, -and another screw added at some distance above the lower one. It was -then successfully screwed down. - -Mr. Brunel, however, ultimately decided on forming the piers of -cast-iron cylinders forced down by loading and afterwards filled with -concrete, and the work was commenced in the spring of 1849. - -With this form of construction all uncertainty of obtaining a secure -foundation was removed, as the pneumatic method was in reserve, in case -of excessive influx of water, to sink the cylinders to the rock, if it -could not be reached by simpler means; and additional cylinders could be -added, so as to obtain any amount of area of base that might be thought -necessary. - -The land piers for the 100 feet spans consist each of three cylinders, -which are 6 feet in diameter, joined together in lengths of 7 feet. The -main pier, which supports one end of the great truss, consists of a -double row of cylinders, six in all, the lower parts of which are 8 feet -in diameter, joined together in lengths of 6 feet. The bottom of each -cylinder was made with a cutting edge, so as to penetrate the ground -easily. - -Most of the cylinders were sunk by the process of excavating the ground -within them and weighting the top, the water being kept down by pumping. -As the ground consisted chiefly of wet sand and shingle, danger was -apprehended from its tendency to run in from the outside, while the -excavation was in progress. This would have diminished the lateral -stability of the cylinders; and great care was taken not to excavate too -near the bottom, but merely to loosen the ground round the cutting edge -and to force the cylinder down by weights. Stiff clay was sometimes used -to prevent the wet sand and gravel from being squeezed in from the -outside. When the cylinders had been sunk to the rock, and it had been -dressed off to form a level foundation, they were filled with concrete -in the same manner as at the Windsor bridge. - -In sinking the cylinders of the main pier, much greater difficulties -were encountered than with those of the land piers, owing to large -boulders and pieces of timber being met with near the bottom. When still -at some distance from the rock, a length of one of these large -cylinders cracked, from its having met with an obstruction. Timber -struts were then fixed within it, until the obstacle was passed, when it -was strengthened by a strong wrought-iron hoop, and forced down to the -rock. - -In April 1851, when the greater number of the cylinders had been sunk, -it was apparent that, from delays due to the influx of water and other -causes, some of them could not be completed by the time that the -superstructure would be ready. Mr. Brunel then decided to employ the -pneumatic method, and by means of this apparatus some of the remaining -cylinders were sunk. In the main pier four auxiliary columns, formed of -7-feet cylinders, were placed close to the others. They were connected -to the 8-feet cylinders by strong brackets, and supplied a great -additional bearing surface. Any slight inaccuracy of position in the -cylinders was corrected by adjusting cones at the level of the ground; -on these cones 6-feet cylinders were built up to the level of the -railway. - -The depth to which the cylinders were sunk and their position are shown -in fig. 3, Pl. IV. From this drawing also the general form of the -superstructure will be understood. - -The bridge is for two lines of way; each line is carried between two -longitudinal girders 7-1/2 feet deep, of the section given in the woodcut, -fig. 11 (p. 208). Each girder has a triangular top flange with a plate -iron vertical web, and a slightly curved plate for the bottom flange. -The roadway girders over the three land spans of 100 feet are in one -piece, and are therefore continuous girders, 300 feet long, supported at -two intermediate points. Those across the main span are also 300 feet -long, and are supported by the main truss. - -[Illustration: IRON BRIDGES] - -The truss for each line of way consists of two suspension chains, one on -each side of the roadway, hung from either side of the ends of a -horizontal circular tube, arched slightly for the sake of appearance, -which rests on piers rising about 50 feet above the level of the rails. -The pier at the land end is of masonry, and the upper part of the middle -pier is of cast iron, resting on the cylinders already mentioned. Each -pier has two archways for the trains to pass through. The chains carry -the roadway girders at four points, and the tube is supported at two -intermediate points in its length by upright standards resting on the -chains. Thus, while the weight of the structure is supported somewhat in -the same manner as in a suspension bridge, the inward drag of the chains -is resisted by the tube. To prevent the framework from being distorted -by unequal loading, it is made rigid by diagonal chains connecting the -upper and lower ends of the two upright standards. - -The main truss may be described as an inverted queen truss. The tube -which has to resist the compressive strain due to the inward pull of the -chains is 9 feet in diameter, and is made of boiler plate 3/4 and 5/8 of -an inch thick, stiffened at intervals by diaphragms. The chains are like -those of suspension bridges, each formed of 12 and 14 links alternately, -these being 10 inches deep, and varying from 3/4 to 11/16 of an inch -thick.[101] - -At the ends of the tube, where the chains are connected to it, there are -several thicknesses of plate, between which the links of the chains are -introduced, and a round pin, 7 inches in diameter, passes through both -plates and links. The strain is thus conveyed from the chains to the -ends of the tube. - -Though the trusses for the two lines of way are completely distinct, -the tubes are braced together horizontally, to increase their stiffness -sideways. - -The woodcut (fig. 11) represents a transverse section of the truss for -one line of way, and shows the circular tube with the internal -diaphragms, the upright standards which support it, the roadway girders, -and the chains. - -[Illustration: _Scale of feet._ - -Fig. 11. Truss of Chepstow Bridge. - -_Transverse Section._] - -In consequence of the great depth of the truss, which is about 50 feet, -or one-sixth of the length, the strains on the several parts are -comparatively small for such a large span. - -The weight of wrought-iron work in each of the trusses of the main -opening is 460 tons, inclusive of the longitudinal and cross girders, -which weigh 130 tons. - -At the points where the roadway girders are intersected by the inclined -chains, they are not fixed to the chains, but rest upon them, rollers -and saddles being placed between; and at the ends of the short -horizontal links, in the middle of the span, there are screws for -adjusting the level of the girders. - -These arrangements were made in order that the roadway girders might not -be strained by the slight alteration in the form of the truss which -takes place when a load comes on the bridge. - -The continuous roadway girders were, in the case of the large span, -supported at six points, and in those over the three land spans at four -points. As the strains on continuous beams, supported at so many points, -had not at that time been fully investigated, Mr. Brunel had the -subject carefully enquired into both by calculation and experiment, and -was thus enabled to proportion the section of the girders to the strains -at each point in their length. Some account of this investigation is -given in the note at the end of this chapter. - -As soon as the ironwork for the first truss was completed, it was put -together parallel to the river bank close to the site of the bridge. The -ends were supported on temporary piers, and the structure was uniformly -weighted with a load of 770 tons, or 2-3/4 tons per foot run. In unloading -it, the weight was taken off from one end of the truss, so as to test -its strength when unequally loaded. The testing having been -satisfactorily completed, the truss was taken to pieces, and -preparations were made for erecting it. - -It was necessary that the river traffic should not be interrupted for -any long period; this circumstance materially influenced the nature of -the design of the superstructure, which was such that no scaffolding was -required in its erection, nor was there any interference with the -navigation for more than a single tide. The truss was made so that it -could be divided into parts, each of which could be lifted separately -and quickly. For the operation of lifting Mr. Brunel determined to use -chain purchases worked by crabs.[102] The tube was temporarily stiffened -by portions of the main chains, arranged so as to form a truss. With -this assistance it was able to carry its own weight when suspended by -the two ends. - -The preliminary operation of slewing the tube to its position on a -platform at right angles to the river, was a work requiring a good deal -of careful contrivance. When this had been accomplished, a pontoon, -consisting of six wrought-iron barges, was placed opposite the end of -the tube, and all was ready for floating it across the river. - -The floating took place on Thursday morning, April 8, 1852. The tube had -been rolled forward on two trucks till its end overhung the pontoon; -and, as the tide rose, the pontoon floated with the end of the tube -resting on it. In order to guide it in a straight line across the river, -hawsers were attached to points on the bank up and down the stream, and -were led to crabs on the pontoon, so that by hauling on either hawser -the tube was kept in its right course. As spring tides at Chepstow rise -40 feet, there is a rapid current except for a very short time. - -The operation of drawing the tube across was commenced at a little after -nine o'clock, and by a quarter to ten the pontoon had reached the other -side safely, and the tube spanned the river. All proceeded with perfect -quiet and regularity under the management of Mr. Brunel, who was -assisted by Mr. Brereton and Captain Claxton. As soon as the pontoon -reached the further shore, the chains of the lifting tackles were -attached to the tube. The tube was lifted in the course of the day to -the level of the railway, and afterwards to its place on the top of the -piers, when the suspension chains and the rest of the truss were -attached to it. The bridge was opened for a single line of way on July -14, 1852. The second tube was floated in a similar manner to the first, -and the bridge was completed shortly afterwards. - -The total cost of the Chepstow bridge was 77,000_l_.[103] - - * * * * * - -The Royal Albert Bridge, which carries the Cornwall Railway across the -River Tamar at Saltash, is the last and greatest of Mr. Brunel's railway -works. - -A railway into Cornwall, crossing the river Tamar, was proposed as early -as 1844. Mr. Brunel at one time thought of carrying the trains across on -a steam ferry similar to those which had been successfully introduced by -Mr. Rendel. - -In 1845 a company was formed and an application made for an Act to -construct the railway either with a steam ferry at Torpoint or by a -bridge at Saltash. The latter plan was sanctioned by Parliament. - -The height of the line shown on the section at the crossing of the Tamar -was 80 feet above high water. The Admiralty, however, required that this -height should be increased. No further steps were taken till the -beginning of 1847, when some preliminary borings and sections were made, -in order to prepare definite plans for the bridge. The facts then -ascertained were so encouraging as to strengthen Mr. Brunel in his -opinion that the difficulties to be encountered would not be found -greater than had been anticipated. - -The river at Saltash is 1,100 feet wide, with a depth in the middle of -about 70 feet at high water. It had at first been intended to construct -the bridge with one span of 255 feet, and six of 105 feet, with -superstructures of timber-trussed arches.[104] In compliance with the -requirements of the Admiralty, the design was altered to two spans of -300 feet, and two of 200 feet, with a clear headway of 100 feet. This -arrangement would have required three piers in deep water. Mr. Brunel -subsequently decided to have only one pier in deep water, and to have -two spans of 465 feet each. It was afterwards found that these could be -reduced to 455 feet.[105] - -Twenty years before, while engaged with his father on the Thames Tunnel, -he had conceived the idea of working under a diving-bell of great -dimensions. Sir Isambard approved of the suggestion, and thought of -applying it in sinking the shafts of the Tunnel. Drawings were prepared, -but the circumstance of a patent for a similar idea having been taken -out by Lord Cochrane partly deterred him from carrying out the project, -though some sketches were afterwards made for constructing a lighthouse -by means of this arrangement. When the construction of the Cornwall -Railway had to be considered, Mr. Brunel thought that his old idea would -be applicable to the difficulties to be encountered at Saltash. - -Although the plan of using a large diving-bell was one which was nearly -certain to be successful, Mr. Brunel thought it probable that a large -cylinder of wrought iron could be constructed to serve as a coffer-dam, -and that after sinking it through the mud, the bottom edge might be -sufficiently water-tight to admit of the water being pumped out, and the -masonry of the pier built in the ordinary manner. - -A trial cylinder, 6 feet diameter and 85 feet long, was made, partly to -ascertain whether or not this plan was practicable, but mainly for the -purpose of thoroughly examining the site of the centre pier, where the -surface of the rock was 80 feet below high water. - -A strong framework was fitted on two gun-brig hulks, with powerful -tackle for lowering and raising the cylinder. After it had been lowered -to the bottom, five borings were taken within it, reaching through the -mud to the rock. The cylinder was then shifted and similar borings made. - -The positions of the borings, one hundred and seventy five in all, were -carefully recorded; and thus a minute and accurate survey was obtained -of the surface of the rock. The site of the pier was afterwards -determined by means of a model constructed from these observations. In -January 1849, when sufficient information had been obtained, the water -was pumped out of the trial cylinder, and the mud excavated down to the -rock. A short piece of masonry was then built, to demonstrate the -practicability of building a pier in such a situation. - -The expenditure of the Company for works of all kinds was shortly -afterwards curtailed as much as possible, and no further progress was -made for upwards of three years. However, information had been gained -which proved that a masonry pier could be built in the middle of the -river, on a good rock foundation which was there covered by a thickness -of about 16 feet of mud. - -During the suspension of the works, all the plans were revised, with the -view of reducing the first cost wherever practicable; and Mr. Brunel -decided not to make the bridge for a double line, even if there were -money forthcoming to do so. His reason for this is given in the -following report to the Board of Trade, made in 1852:-- - - This bridge had been always assumed to be constructed for a double - line of railway as well as the rest of the line. In constructing - the whole of the line at present with a single line of rails, - except at certain places, the prospect of doubling it hereafter is - not wholly abandoned, but with respect to the bridge it is - otherwise. - - It is now universally admitted that when a sufficient object is to - be attained, arrangements may easily be made by which a short piece - of single line can be worked without any appreciable - inconvenience.... This will make a reduction of at least - 100,000_l._ - -In the summer of 1852 the designs of the bridge were matured, and by the -beginning of 1853 the Admiralty had approved of them; the work of -constructing the great cylinder for the centre pier was then commenced. - -It was determined to provide for the possibility of having to employ the -pneumatic process. The cylinder had a diameter of 35 feet at the -bottom, and about 20 feet above the lower end of it a dome was made to -form the roof of the diving-bell; from the centre of the dome rose a -tube 10 feet in diameter to the level of the top of the great cylinder. -As a diving-bell of this size, under 80 feet of water, might have proved -unmanageable, an annular space, forming a gallery or jacket of 4 feet in -width and 20 feet high, was formed round the inner circumference of the -bottom of the cylinder below the dome. This annular space was divided by -radial vertical partitions into eleven compartments, and was connected -at the top by an air-passage with a 6-foot cylinder, which was placed -eccentrically inside the 10-foot cylinder already mentioned, and served -as a communication between the outside and the annulus. On the top of -the 6-foot cylinder were placed the air-locks of the pneumatic apparatus -which had been used at Chepstow. Thus air might be pumped into the -annular space, the water expelled, and the work carried on without -having to use air pressure under the whole of the dome. In that part of -the 10-foot cylinder which was not occupied by the 6-foot cylinder a -powerful set of pumps were fixed to keep down the water in the central -space, and diminish the pressure under which the men worked, thus -utilising whatever advantage could be gained from the great cylinder -acting as a coffer-dam. As it had been ascertained that the surface of -the rock dipped to the south-west to the extent of about 6 feet in the -width of the pier, the bottom of the cylinder was made oblique, so as to -fit the surface of the rock. These arrangements are represented in the -transverse section of the great cylinder (Pl. V. p. 218).[106] - -The great cylinder, having been constructed on the river-bank, was moved -down to low water on launching-ways, and floated off by the rising tide. -Guided between four pontoons, it was finally sunk in correct position in -June 1854. - -Some delay in penetrating the mud was caused by a bed of oyster shells, -which had to be cut through by one edge of the cylinder. In consequence -of some irregularities of the surface of the rock, the cylinder at first -deviated considerably from an upright position; and it was necessary to -use the pneumatic apparatus to gain access to the rock, and excavate it. -The height of the annulus below the dome was such that it was not quite -filled by the mud when the cylinder rested on the bottom. The work of -getting the mud out of the annular space was much facilitated by the -division of it into compartments. - -By February 1855, the cylinder had been sunk to its full depth in an -upright position, and it then rested everywhere on the rock, its lowest -point being 87 feet 6 inches below high water. - -Much trouble was given by a spring of water issuing out of a fissure in -the rock, in one of the compartments, but the flow was stopped by -driving close sheet piles into the fissure. The rock in the annulus was -dressed, and the space filled by a ring of granite ashlar masonry which -was built to a height of about 7 feet all round. The state of the work -at this time is that represented in the section of the cylinder, (Pl. V. -p. 218). - -The rock consisted of greenstone trap, so hard that tools could with -difficulty be got to work it. When the ring of masonry was completed, it -was expected that the bottom might be sufficiently water-tight to act as -a coffer-dam, and allow of the mud being taken out from the central part -of the cylinder, below the dome. But the pumping power was not at first -sufficient for this purpose, and it was thought that it would be -necessary to employ the pneumatic process in this space also. - -However, by rapid and incessant pumping the water was lowered so as to -allow of the mud and rock being excavated, and the masonry in the -central space built without having again recourse to the use of air -pressure. The leakage water was conveyed to two wells, formed of -cast-iron pipes built into the masonry, from which the water was pumped. -The inner plates of the annulus were cut out, and the work in the centre -which consisted of granite ashlar set in cement was thoroughly bonded -into the ring of masonry already built. When the work was carried up to -the level of the dome, both the dome and the internal 10-foot cylinder -were cut out and removed. When the building had been carried up some -height, the pump wells were filled with cement concrete, and the influx -of water stopped. Finally, about the end of 1856, when the masonry was -completed to the cap of the pier, the upper part of the great cylinder -was unbolted and taken ashore, it having been made in two halves with -that object. Thus the most difficult part of the undertaking was -successfully completed.[107] - -The centre pier of the Saltash bridge is, like many great engineering -works, out of sight, and little regarded by any but professional men. -The rest of the bridge forms a striking feature in a beautiful -landscape, and its appearance is well known. - -The whole length of the bridge is about 2,200 feet, and is divided into -two great spans over the river of 455 feet each and seventeen side -spans, varying from 70 to 90 feet, which are on sharp curves. The piers -of the side spans, as well as the two large piers carrying the land ends -of the main trusses, are of masonry. The masonry of the centre pier is -35 feet in diameter, and is carried up about 12 feet above high water -level. On it stand four cast-iron octagonal columns, rising up to the -level of the railway. The piers which support the ends of the great -trusses are constructed with arched openings, through which the trains -pass. - -The transverse elevation of the centre pier (Pl. V.) shows the octagonal -columns connected by cast-iron open-work, and the arched opening. The -upper part of the centre pier is a cast-iron standard, and that of the -land piers is of masonry cased with cast iron.[108] - -The elevation shows the great height of the structure, the rails being -190 feet and the highest part of the truss 260 feet above the lowest -point of the foundations. - -The railway is carried over each of the smaller openings between two -longitudinal girders, and over the main spans it is carried between -similar longitudinal girders, which are suspended at intervals from the -main truss. - -[Illustration: THE ROYAL ALBERT BRIDGE] - -Each truss consists of a wrought-iron oval tube, which forms an arch, -and of two suspension chains,[109] one on either side of the tube, -connecting its two ends. The rise of the arched tube above its -abutments on the top of the piers is the same as the fall of the -suspension chains below the same level. At eleven points in the length -of the truss the chains are connected to the tube by upright standards, -which are braced together by diagonal bars, in order to resist the -strains due to unequal loading. The roadway girders are suspended from -the truss at the upright standards already mentioned, and at an -intermediate point between each of them. - -The truss has the great depth of 56 feet in the centre; this conduces -materially to the economy of the construction, as it diminishes the -strain upon the principal parts, the tube and the chains, and so enables -them to be made of smaller dimensions. - -[Illustration: Fig. 12. Truss of Saltash Bridge. - -_Transverse section._ - -_Scale of feet._] - -The woodcut (fig. 12) is a transverse section in the centre of the -truss, showing the oval tube, the chains, the upright and standards, the -roadway girders. - -The tube is made oval in section with the greater diameter horizontal, -in order that it may have stiffness sideways under the compressive -strain, and that the main chains may hang vertically at such a distance -as to leave room for the roadway between them. The tube is 16 feet 9 -inches broad and 12 feet 3 inches in height. Each chain consists of two -tiers of links, each tier formed of 14 and 15 links alternately. These -are 7 inches deep and about 1 inch thick. The arrangements of the -ironwork of the tube and its connections with the main chains are -generally similar to those at Chepstow. - -The truss may be described as a combination of an arch and a suspension -bridge, half the weight being placed on the one and half on the other, -the outward thrust of the arch on the abutments being counterbalanced by -the inward drag of the chains. - -The mechanical arrangement of the Saltash truss is similar to that of -the one at Chepstow.[110] The tube, resting on standards, the railway -passing beneath, the suspension chains hung from either side of the -tube, the upright standards, and the diagonal bracing are common to the -two structures. - -The difference in the form of the two trusses is principally the result -of the difference in the circumstances attending the construction of the -bridges at Chepstow and Saltash. The design of the Chepstow truss was -chiefly determined by the necessity of lifting up the separate parts of -it under conditions of peculiar difficulty; while at Saltash the mode of -floating and lifting the superstructure had great influence in the -preparation of the design. - -On Plate V. (p. 218) is given an elevation of one span of the Saltash -bridge, and a general elevation on a smaller scale of the whole bridge. - -The total weight of wrought ironwork in the superstructure of each span -is 1,060 tons.[111] - -The trusses at Saltash were not lifted in parts, as at Chepstow; for, -as the river was divided by the centre pier into two openings, one of -them could be left clear for the navigation, and each truss, with its -roadway girders attached, could be raised to its position slowly and in -one piece. The trusses were constructed parallel to the river on the -Devonshire side, close to the site of the bridge. When the truss for the -Cornwall or western span was completed, temporary piers were erected to -support the ends, and the scaffolding having been removed, the roadway -was loaded with 1,190 tons, uniformly distributed.[112] - -This test having proved satisfactory, preparations were made for -floating the truss. Docks were made underneath it near the two ends, and -in each of these docks two iron pontoons were placed. Valves were then -opened to admit water, and the pontoons were allowed to sink on timbers -prepared to receive them. - -Upon each pair of pontoons was erected an elaborate framework of timber -to carry the weight of half the truss, or between 500 and 600 tons. The -framework consisted of stout timber props, some of them 40 feet long, -extending from the pontoon to the arched tube, and was attached to the -tube by iron suspension rods, so that when the operation of floating was -completed, the pontoons would be free to pass from underneath the truss. - - * * * * * - -Mr. Brunel had previously taken part in operations of this nature. When -Mr. Robert Stephenson was about to undertake the floating of the tubes -of the Conway and Britannia bridges, he asked his friends Mr. Brunel -and Mr. Locke to give him their assistance. They were present at all, or -nearly all, these difficult operations, and Mr. Brunel had an active -share in the work, especially in the floating of the first Conway tube. -By Mr. Brunel's advice Mr. Stephenson had obtained the services of -Captain Claxton to superintend the nautical part of the work; and -Captain Claxton was, as a matter of course, with Mr. Brunel in a similar -capacity at Chepstow and Saltash. - -At Saltash fortunately there was not so swift a tide as there had been -at the Britannia and Conway floatings. - -In order to haul the truss out, warps were laid from the pontoons to a -gun-brig hulk near the centre pier, and to a barge higher up the river. -On this barge were also placed ready for use the ends of four warps, -leading to capstans and crabs on board vessels moored at various points. -To keep the truss from being drifted up or down the river while being -moved out, radius lines were laid from the pontoons to moorings, with -arrangements for hauling in on them if required. - -In order to ensure his directions being clearly understood and promptly -attended to, Mr. Brunel assembled a number of his assistants, one of -whom was placed as 'Captain' in each of the vessels containing the -hauling capstans, to superintend the men, and to execute orders. These -orders were given by signals. - -It was most important that the attention of the captain should not be -diverted by looking out for the signals, and that there should be no -chance of a signal not being seen by him because he was attending to -some other of his duties. There was, therefore, in each vessel an -assistant whose sole duty it was to watch for the signals, to give the -appropriate interpretation to the captain, and to acknowledge the signal -by a flag corresponding to that by which it was given. - -Mr. Brunel directed the operations from a platform in the centre of the -truss. The signals were given from a smaller platform immediately above, -and were made by red and white flags, held in front of black boards, -which were turned towards the vessel signalled to. Printed papers -containing instructions were distributed to all engaged; the signalling -was carefully rehearsed, as also was every other part of the operations -which could be tried beforehand. - - * * * * * - -September 1, 1857, was the day fixed for the floating. During the -morning, the men, about 500 in number, assembled at their stations on -the vessels and pontoons. Captain Claxton had command of the -arrangements afloat, and as a reserve force to act in any emergency -several boats were lent from H.M.S. 'Ajax' and the Dockyard. With Mr. -Brunel were Mr. Brereton and Captain Harrison, the commander of the -'Great Eastern.' Mr. Robert Stephenson was expected, but a serious -attack of illness prevented him from being present. - -At about one o'clock in the afternoon signals from the tops of the -temporary piers on which the truss rested, showed that the ends had been -lifted three inches clear. Mr. Brunel then gave the signal for the men -in the pontoons to haul on the warps, and the great structure glided -slowly out to the centre of the river. A pause was then made, while the -warps which were to swing the truss round into its place were being -attached to the pontoon which was farthest from the centre pier. When -this was done, the different ropes were hauled upon in obedience to -signals, so as to keep the other pontoon close to the centre pier, upon -which, as a pivot, the truss swung round in a quarter circle till it -occupied the whole of the western half of the river, and was brought -close to its appointed resting-place. It was finally adjusted to its -exact position by strong tackles attached to the piers. Water was then -admitted into the pontoons; and, as the tide fell, they were allowed to -drift away, leaving the truss resting on the piers, the roadway girders -being but a few feet above the water. - -The whole operation was conducted with the most perfect order and -regularity. The beauty of the scenery and the changing effect produced -by the truss in the various positions it assumed as it was being moved -forward and swung round into its place, rendered the operation as -interesting to the spectators as its results were satisfactory to Mr. -Brunel and to those who assisted him.[113] - - * * * * * - -In the task of lifting the truss, as well as in that of floating it, Mr. -Brunel had the great advantage of the experience gained at the Britannia -Bridge. There the piers were built first, and the tubes hauled up with -link chains by hydraulic presses placed on the tops of the towers. The -design of the piers at Saltash did not allow of this plan being adopted, -and they were built up under the truss as it was lifted. Under each end -of the truss were three hydraulic presses; the two outside presses -combined, or the middle one by itself, were sufficient to lift the -weight. Mr. Brunel had also at first intended to have strong -screw-jacks, which were to be kept screwed up underneath the truss, and -so to support the weight, if by any accident the presses failed. A -modification of this plan was adopted; the rams of the presses had a -screw thread cut on them, and a large nut on each was kept screwed up -hard against the top of the press as the ram emerged from it. As an -additional precaution, timber packing, in thin layers, was placed in the -space between the completed portion of the pier and the end of the truss -as it was lifted. Great care was thus taken to guard against any mishap. - -The tube was lifted 3 feet at a time at each end. The operation went on -slowly, in order to allow the masonry of the land pier to set after it -had been built up underneath the truss. The work was carried on with -great system and care under the immediate superintendence of Mr. -Brereton. Mr. Brunel was only able to be present during one of the -lifting operations, as he was then engaged in the launch of the 'Great -Eastern.' - - * * * * * - -By July 1858, the first truss had been lifted to its full height, and -the second truss was ready for floating. The arrangements were generally -similar to those on the previous occasion; the course, however, to be -traversed by the pontoons was more intricate than on the previous -occasion, as the land pier on the Devonshire side of the river, over -which the first truss had passed, had been built up to receive the end -of the second. - -This truss had, therefore, to be moved first outwards till the pontoons -were clear of the docks, then it had to move endways up the river, and -to swing round into position. Mr. Brunel was obliged to remain abroad -from ill-health, and Mr. Brereton conducted the operations. Although the -weather was not favourable, and the wind high, the truss was safely -landed on the piers; and was afterwards raised in the same manner as the -first one.[114] - -The general elevation, Plate V., shows the proportions of the bridge. On -the Devonshire side, the side spans pass over fields, and on the -Cornwall side over the town of Saltash. - -The general effect of the bridge is in no way heightened by an -expenditure of money on architectural ornament; for, with the exception -of a few unimportant mouldings, the bridge is absolutely unadorned. The -total cost was 225,000_l._--a very moderate expenditure, especially when -the difficult work at the centre pier is taken into account. This result -is due not only to the careful manner in which all the details of the -design were prepared, but also to the great attention given throughout -to the construction. - -His Royal Highness the Prince Consort, as Lord Warden of the Stannaries, -permitted the bridge to be called the Royal Albert Bridge, and consented -to open it in person. The ceremony was performed on May 3, 1859. Mr. -Brunel was compelled to be absent on the Continent, for the sake of his -health, and was represented on the occasion by Mr. Brereton. - -After Mr. Brunel's return to England, he paid a hurried visit to the -Cornwall Railway, and, for the first and last time, saw in its completed -state the great work on which he had expended so much thought and care. - - -NOTE, (pp. 182, 194, 209). - -_Experiments on Matters connected with Bridge Construction._ - -No account of the structures designed by Mr. Brunel would be complete -without a reference to the elaborate care he always took, wherever it -was practicable, to satisfy himself by experiment of the qualities of -the materials employed, and of the correctness of the principles -followed. It would not here be possible to give a detailed record of all -his experiments, but an account of some of the methods employed by him -will be interesting. - -Some of the larger of Mr. Brunel's experiments on cast and wrought-iron -girders have already been mentioned.[115] He scarcely ever made any -large girder or framework without having it fully tested, and he made -extensive and elaborate experiments, most of them on a very large scale, -on the strength of some of the materials and component parts of his -different structures. - -Among the large scale experiments tried by Mr. Brunel, were those on the -compressive strength of yellow pine-timber, which were made at Bristol -in 1846, and were on specimens from 10 to 40 feet in length, and from 6 -to 15 inches square. A framework of four upright pieces of whole timber, -nearly 50 feet high, contained four strong bars of wrought iron, placed -vertically, and attached at their lower ends to the cylinder of a -hydraulic press. Along these bars, a casting could be moved, and -fastened at different heights by keys, in such a manner as to have its -under-surface, which was planed, perfectly horizontal. The ends of a -specimen having been made exactly square to its length, it was put in -this apparatus, with the upper end bearing against the lower surface of -the movable casting, and the lower end resting on the top-surface of the -ram of the hydraulic press, which was also planed and adjusted so as to -be horizontal. The keys, which attached the movable casting to the bars, -were now driven tight, and the pump of the press worked, weights being -placed on the end of the lever, to correspond with increments of -pressure on the ram. These weights were added gradually, until the -specimen gave way. The accuracy of this mode of measuring the pressure -was tested by direct loading of the ram with rails, which was repeated -several times during the course of the experiments, so as to guard -against any change in the amount of friction of the press. For each -increment of weight, the compression of the specimen was measured on its -four faces, and its deflection, or amount of bending, on two adjacent -faces. The transverse stiffness of long specimens was also tried, by -supporting them at each end, and loading them in the middle. The -deflection in the middle thus observed corresponded very closely with -what might have been expected from the observations on the direct -compression; and from the constants so obtained, the strength of those -specimens, whose length was very great as compared with their transverse -dimensions, could be obtained by Euler's theory, but for the stouter -specimens the strength per square inch was found to be nearly constant. -From these experiments, a complete practical knowledge of the properties -of yellow pine timber, when subjected to end pressures, was obtained, -knowledge new at the time, and almost essential to Mr. Brunel in -designing the many viaducts which he afterwards constructed. - -Mr. Brunel also made experiments on the strength of pine timber when -exposed to pressure on the side or at right angles to the fibre. By this -means he determined the area which it was desirable to provide for the -washers of bolts, and the weight which might safely be placed on -transverse timbers or sills of viaducts. - -Mr. Brunel's experiments on riveting were also important. Most of these -were made with specimens 20 inches wide, and half an inch thick. They -were compared with specimens of solid iron, of the same quality and -thickness as the riveted specimens, and also the same width minus the -rivet holes, so as to have equal efficient sectional areas. Double -covering plates and double riveting were used in all cases, the -variation being in the widths of the covering plates, and the number and -arrangement of the rivets. The experiments were continued until thirty -in all had been made, and the strongest form of joint was considered to -have been arrived at. - -In connection with the lifting of the parts of the Chepstow Bridge, an -elaborate series of experiments was made on ropes, chains, and -wire-rope, so as to ascertain which of these it was desirable to employ, -as possessing the greatest advantages. The experiments made were of two -kinds, one to determine the absolute strength of the specimen when -subjected to a straight pull, and the other to observe what took place -when it was worked over a sheave. In the first set the specimen was held -at each end in the jaws of a pair of wrought-iron clamps, which were -tightened up by means of screws. One of the clamps was attached to a -fixed beam, and from the other was suspended a large cylindrical tank, -which was gradually filled with water until the specimen gave way, the -breaking strain being the weight of the tank and water. This weight was -ascertained by actual weighing with a steelyard when the water in the -tank was at different heights. Observations on the extension, shrinkage -of the circumference, and change in the pitch of the spiral of the rope -were made with different loads, and the strength of a sufficient number -of the yarns of which the rope was composed was tried to ascertain the -loss of strength by combining the yarns into a rope. In the second set -the specimen, clamped as before, was passed over a sheave, the axle of -which rolled horizontally on planed cast-iron plates, in order to -diminish friction. To each clamp was attached a cylindrical iron tank. -Water being admitted to the highest tank until downward motion -commenced, its influx was stopped, and the tank descended, the other one -rising. Water was then admitted to the now highest tank until motion -again commenced, and this process was repeated until the specimen gave -way, the tanks getting fuller of water at each movement, at which times -the difference of weight of the two tanks was observed. This, minus the -slight friction of the apparatus, represented the rigidity of the rope. -The extensions were observed as in the first set of experiments. - -The specimens consisted of hemp, manilla, shroud laid and hawser laid -ropes, from 8 to 10 inches in circumference, round and flat wire ropes, -and chains of different sizes of about the same strength as the ropes. -The sheaves also were of different diameters. These experiments resulted -in Mr. Brunel deciding to use chains for lifting the bridge, and this -mainly from the circumstance that chains work more satisfactorily over a -sheave than either hemp or wire ropes. - -Some small scale experiments made by Mr. Brunel are deserving of notice. -These were made to verify calculations on the longitudinal girders of -the Chepstow truss, which are virtually continuous beams of five unequal -spans. It was desirable to test the results of analysis by experiment, -in order to be assured that no errors had been committed in its -application. Mr. Brunel accordingly devised the following simple form of -experiment for this purpose. A deal rod, exactly half an inch square and -38 feet long, quite free from knots, was supported on props of equal -height, above the perfectly horizontal and planed surface of a large -beam of timber. The props were placed so as to correspond relatively to -the actual spans, and the rod was loaded uniformly by means of a chain. -It was thus bent into an elastic curve, the ordinates of which were very -carefully measured, at every foot along the length, by a finely divided -scale and magnifier. The pressure on each prop was also determined, by -removing any particular one, and suspending the point of the rod -immediately over it to a steel-yard, the weight being observed when the -point of the rod was exactly at the same level as before the prop was -removed. The obvious condition, that the sum of the pressures on the -props should be equal to the weight of the rod and its load, furnished a -satisfactory means of testing the results of these weighings. The rod -being turned over on each of its four sides, the experiments were -repeated, and the average taken, in order to eliminate the effects of -initial curvature, or of unequal elasticity. Diagrams of the elastic -curves were then made, showing the correspondence of theory with -experiment, and this was so close as to leave no doubt that a true -knowledge of the nature of the strains had been arrived at. One of these -diagrams is given by Mr. Edwin Clark in his work on the 'Britannia and -Conway Tubular Bridges,' vol. i. p. 462. - -By modifications of the plan Mr. Brunel adopted in this experiment, the -strains on continuous beams of varying section may be ascertained with -considerable accuracy. - - - - -CHAPTER VIII. - -_STEAM NAVIGATION. THE 'GREAT WESTERN' STEAM-SHIP._ - -A.D. 1835--1847. AETATIS 30--42. - - INTRODUCTION TO THE CHAPTERS ON STEAM NAVIGATION--FORMATION OF THE - GREAT WESTERN STEAM-SHIP COMPANY--COMMENCEMENT OF THE BUILDING OF - THE 'GREAT WESTERN'--REPORT ON SELECTION OF THE BUILDERS OF THE - ENGINES (JUNE 18, 1836)--STATEMENTS OF DR. LARDNER ON THE PROBABLE - FAILURE OF A LINE OF STEAM-SHIPS BETWEEN ENGLAND AND - AMERICA--VOYAGE OF THE 'GREAT WESTERN' TO LONDON--COMPLETION OF THE - ENGINES--HER RETURN TO BRISTOL--FIRE ON BOARD AND ACCIDENT TO MR. - BRUNEL--VOYAGE TO NEW YORK--COMPARISON BETWEEN THE PERFORMANCES OF - THE 'GREAT WESTERN' AND THE 'SIRIUS'--SUBSEQUENT HISTORY OF THE - 'GREAT WESTERN'--NOTE: DIMENSIONS OF THE SHIP AND ENGINES. - - -It will readily be conceded that Mr. Brunel's railway works, which have -formed the subject of the five preceding chapters, would have given him -ample employment for the thirty years of his professional life. - -Nevertheless, during almost the whole of that period--namely, from 1835, -the year of the passing of the Great Western Railway Bill, to his death -in 1859--he was also engaged in the accomplishment of undertakings which -had for their object the systematic development of Ocean Steam -Navigation.[116] - -The 'Great Western,' the first steam-ship which made regular voyages -across the Atlantic, the 'Great Britain,' the first large iron -steam-ship, and the first large ship in which the screw propeller was -used, and, lastly, the 'Great Eastern,' were Mr. Brunel's works, built -under his direction, in the midst of his other engrossing occupations, -and at the sacrifice of his health and life. - -The history of these projects will contain records of many -disappointments as well as of success; for no great and novel -undertaking can be perfected at once and without changes of plan and -arrangement. As engineer to the Companies which built these steam-ships, -Mr. Brunel advised the adoption of measures strongly in opposition to -current popular opinion, and far bolder and more daring than even his -recommendation of the broad gauge and the atmospheric system. The -results obtained have verified his calculations, and the conclusions he -sought to establish are now so generally accepted that it is difficult -to believe that they were ever questioned. No one now has any doubt that -large vessels can with safety be built of iron, or that the screw -propeller can be advantageously employed in ships of war and the -mercantile navy; no one can now deny that it is practicable for -steam-ships to make long voyages across the ocean with regularity and -speed. - - * * * * * - -A detailed account will now be given of the ships whose performances -first demonstrated the truth of these propositions. - -Although the 'Great Western' was the first steamer which was built for -regular voyages between Europe and America, the first attempt to use -steam in the direct voyage across the Atlantic was made by an American -ship of 300 tons burden, called the 'Savannah,' and built at New York. -Her engines were of small power, with paddles made to ship and unship. -She made only two voyages to and from Europe: in the first of these she -left the port of Savannah on May 25, and anchored at Liverpool on June -20, 1819. - -No further advance in Ocean Steam Navigation seems to have been -attempted until 1835. In the October of that year, at a meeting of the -Directors of the Great Western Railway Company, at Radley's Hotel, in -Bridge Street, Blackfriars, one of the party spoke of the enormous -length, as it then appeared, of the proposed railway from London to -Bristol. Mr. Brunel exclaimed, 'Why not make it longer, and have a -steamboat to go from Bristol to New York, and call it the "Great -Western?"' This suggestion was treated as a joke by most of those who -heard it; but at night Mr. Brunel and Mr. T. R. Guppy, one of the -Directors, talked it over, and afterwards consulted three of the leading -members of the Board--Mr. Scott, Mr. Pycroft, and Mr. Robert Bright. -They took up the idea warmly, and a committee was formed to carry out -the project. - -As a preliminary measure, Mr. Guppy and Captain Christopher Claxton, -R.N., made a tour of the great ship-building ports of the kingdom, in -order to collect information. The results of their inquiries were -embodied in a report, dated January 1, 1836, which describes at great -length the advantages to be gained in large vessels. The manuscript was -submitted to Mr. Brunel previously to its publication, and he inserted -the following passage:-- - - The resistance of vessels in the water does not increase in direct - proportion to their tonnage. This is easily explained; the tonnage - increases as the cubes of their dimensions, while the resistance - increases about as their squares; so that a vessel of double the - tonnage of another, capable of containing an engine of twice the - power, does not really meet with double the resistance. Speed - therefore will be greater with the large vessel, or the - proportionate power of the engine and consumption of fuel may be - reduced. - -This was an important addition to the report, for it enunciates the -principle which governed Mr. Brunel in determining the dimensions and -power, not only of the 'Great Western,' but also of the 'Great Britain' -and 'Great Eastern' steam-ships. - -Immediately after the publication of this report a Company was formed in -Bristol called 'The Great Western Steam-Ship Company,' Mr. Peter Maze -being the Chairman, and Captain Claxton the Managing Director. Captain -Claxton's exertions in the service of the Company from its formation to -its dissolution were unremitting and invaluable. He was also, from the -date of Mr. Brunel's first connection with Bristol, one of his most -intimate friends, and his confidential adviser on all points on which -nautical experience was of value.[117] - -Mr. Patterson (an eminent ship-builder of Bristol) was selected to -superintend the building of the first ship, under the direction of a -'Building Committee' consisting of Captain Claxton, Mr. Guppy, and Mr. -Brunel. Whenever railway business called Mr. Brunel to Bristol, which at -this time was at least once in every week, the Committee and Mr. -Patterson used to meet at the office, or at Captain Claxton's or Mr. -Guppy's house, and often sat far into the night discussing the details -of the design of the ship.[118] - -One of the most important questions which occupied Mr. Brunel's -attention was the selection of the builders of the engines. Tenders were -invited; and on receiving them, he addressed the following report to -Captain Claxton, the Managing Director:-- - - - June 18, 1836. - - In considering the three tenders for the supply of marine engines - for your first vessel, which you have submitted to me for my - opinion, I have assumed that the interests of the company are - paramount, and that all feelings of partiality towards any - particular manufacturer or any local interest must yield to the - absolute necessity, in this the first and the boldest attempt of - the kind yet made, of not merely satisfying yourselves that you - will obtain a good engine, but also of taking all those means of - securing the best which in the eyes of the public may be - unquestionable. In this view of the case, if you agree with me, I - think you will consider that, provided the prices are fair - individually, the relative amount of the tenders is a secondary - consideration. - - I assume, also, that the high respectability of all these parties - would ensure equally from either the best materials and - workmanship, and I shall confine myself simply to pointing out a - few of the conditions peculiar to the engines which you require, - and the means which the different parties have of complying with - these conditions. - - I need hardly remind you that, owing to the lateness of the season, - you will require that the vessel should be prepared to run her - first voyage almost immediately after the engines are fixed. You - will remember, also, that it will be the longest voyage yet run; - that in the event of unfavourable weather a total failure might be - the result of the engine not working to its full power, or - consuming too great a quantity of coals--a very common occurrence - with engines apparently well made, after six or eight days' - constant work; and, lastly, that the future success of the boat as - a passenger ship--nay, even of the company's boats generally, and, - to a great extent, and for some time, the reputation of Bristol as - an American steamboat station, may depend upon the success of this - first voyage. It is indispensable, therefore, to secure as far as - possible a machine which shall be perfect in all its details from - the moment of its completion. There may be time for a few trials - for ascertaining the fact of its completion, but there will be none - for effecting any alterations should they be found necessary, or - for making any experiments. The machinery which you require to be - so perfect is by no means an ordinary steam-engine. - - Marine engines of 80 or 90, and even some of 100 horse-power, are - mere models on a large scale of the ordinary-sized engines. Engines - of 160 or 180 horse-power each would be unmanageable without many - material modifications in the details; the arrangement must be - different, and, as the strength of materials remains the same, the - proportionate dimensions of the parts must be modified. Many - contrivances of this description have been introduced into the - large engines of 110 horse-power each made for the Navy. From 110 - to 160 is still another and a very great stride. Those who have led - the way in the first step are certainly the most likely to be aware - of the difficulties of the second, and to be able to appreciate - them better, and be more prepared to overcome them than those who - have as yet only manufactured, however successfully, engines of the - ordinary class. Of three parties tendering.... Messrs. Maudslay - have made by far the largest number, and have for some years led - the way in the introduction of the largest armed steamboats; and - there can be no question as to the fact that they are the oldest - manufacturers of marine engines, that they are themselves the - originators of the greatest number of the improvements of the day, - that they have made the largest engines yet made, and the greatest - number of large engines of all sizes; and, lastly, that they have - the principal supply of engines for the large war ships now used - for the Navy, and have had hitherto the sole supply of all above 70 - horse-power. With these facts before you, it remains only for you - to consider how far you agree with me in the conclusion I have come - to, and which I have no hesitation in expressing--that I think you - will be safest, in the peculiar case of the first ship, in the - hands of the parties who have had most experience, and that Messrs. - Maudslay are those persons. Their price is, I think, moderate. - -This report was read by Mr. Brunel at a meeting of the Board, summoned -at his request; the Directors adopted his advice, and accepted the offer -of Messrs. Maudslay & Field, of Lambeth.[119] - -The 'Great Western,' for so the ship was called, had not been long -commenced when a somewhat celebrated controversy arose, in which the -correctness of Mr. Brunel's views was questioned by the late Dr. -Dionysius Lardner. - -The circumstances which led to this discussion were as follows:-- - -The British Association for the Advancement of Science held its sixth -meeting at Bristol in August 1836; and, as Dr. Lardner was announced to -lecture on Transatlantic Steam Navigation, great interest was felt in -Bristol on the occasion. - -After some postponement, he delivered his lecture on August 25, to a -crowded meeting of the Mechanical Section. The proceedings of the -Association unfortunately do not give any report of Dr. Lardner's -observations; but, as in his latest work on the subject[120] he speaks -in commendatory terms of the report given in the 'Times' newspaper, that -account may be relied on as correct. - -In the 'Times' of August 27, 1836, it is stated that in the course of -his lecture Dr. Lardner said,-- - - Let them take a vessel of 1,600 tons, provided with 400 horse-power - engines. They must take 2-1/3 tons for each horse-power, the vessel - must have 1,348 tons of coal, and to that add 400 tons, and the - vessel must carry a burden of 1,748 tons. He thought it would be a - waste of time, under all the circumstances, to say much more to - convince them of the inexpediency of attempting a direct voyage to - New York, for in this case 2,080 miles was the longest run a - steamer could encounter: at the end of that distance she would - require a relay of coals. - -There is no detailed report remaining of the animated discussion which -followed the lecture, and in which Mr. Brunel took part. He exposed -several errors in Dr. Lardner's calculations, but failed to produce any -effect upon the majority of those present, who were powerfully impressed -by the lecturer's dogmatic assertions. - -Those assertions seem to have had a wide circulation beyond the walls of -the lecture-room; and if Dr. Lardner's arguments were sound, and if -transatlantic steamers ought to have taken their departure from 'the -most western shore of the British Isles,' the enthusiastic advocate of a -railway scheme in Ireland might well exclaim,-- - - The promoters of this vast object stand forewarned of defeat. Dr. - Lardner, who has bestowed a great deal of pains in arguing the - bearings of this undertaking, has pronounced it impracticable; and - I entirely agree with him in his conclusions. The effort, - nevertheless, will be made; the genius of English enterprise will - hazard the consequences; and every honest spirit that shall hear of - the brave British crew which will embark upon that perilous - expedition will feel his heart beating high for the - merchant-sailor, whom nothing can deter. He will sail; but, though - dangers will encompass him, and destruction appear, there is yet a - hope for his ultimate success. Let us cheer ourselves with the - expectation that, as the exhausted mariner returns, he will fall in - with the western shores of Ireland; that, worn out and hopeless of - home and comfort upon earth, the Shannon will win him to her bosom; - that, invited by the graceful sinuosities of that noble stream, and - the rich and fertile lands around, he will advance to this - convenient and improving city; and as he rests within its walls - that he will exclaim, 'This is the place from which I ought to have - set out, for here have I returned with ease and safety!'[121] - -Dr. Lardner's views are repeated in an article in the 'Edinburgh Review' -for April 1837 (vol. lxv.); and in the report of the proceedings of the -British Association for 1836 (p. 130 of the proceedings of the -sections), the reader is referred to this article, apparently as a -substitute for an abstract of the lecture. - -The following _resume_ is there given of the lecture:-- - - The conclusions at which he arrived were briefly these: that, in - the present state of the steam-engine as applied to nautical - purposes, he regarded a permanent and profitable communication - between Great Britain and New York by steam-vessels making the - voyage _in one trip_ as in a high degree improbable; that since the - length of the voyage exceeds the present limits of steam-power, it - would be advisable to resolve it into the shortest practicable - stages; and that, therefore, the most eligible point of departure - would be the most western shores of the British Isles, and the - first point of arrival the most eastern available parts of the - western continent; and that, under such circumstances, the length - of the trip, though it would come fully up to the present limit of - this application of steam-power, would, nevertheless, not exceed - it, and that we might reasonably look for such a degree of - improvement in the efficiency of marine engines as would render - such an enterprise permanent and profitable. (P. 119.) - -Among other objections to long voyages the reviewer enumerates the -incrustation of boilers, and the choking of smoke flues; and then, with -reference to the quantity of fuel required, he proceeds:-- - - In proportion as the capacity of the vessel is increased, in the - same ratio or nearly so must the mechanical power of the engines be - enlarged, and the consumption of fuel augmented.... It is therefore - demonstrable that, in the present state of steam navigation, if - this voyage shall be accomplished in one uninterrupted trip, the - vessel which performs it must, whatever may be her power and - tonnage, be capable of extracting from coals a greater mechanical - virtue, in the proportion of three to two, than can be obtained - from them by the combined nautical and mechanical skill of Mr. - Lang, the builder of the 'Medea,' and Messrs. Maudslay and - Field.... That the passage from Liverpool to New York cannot on any - occasion be made in one run by a steam-ship we do not maintain.... - The average time of the outward voyage to New York is thirty-six - days, and we say that when the circumstances of wind and water are - such that a sailing vessel would require that time to make the - passage, a steamer cannot make it without an intermediate supply of - fuel. (Pp. 127, 139, 143.) - -To sum up Dr. Lardner's views in his own words written at about this -time,[122] 'We have as an extreme limit of a steamer's practicable -voyage, without receiving a relay of coals, a run of about 2,000 -miles.'[123] - -It will be seen from these extracts that the proposition Dr. Lardner -laid down as the basis of his 'demonstration' was, that the power of the -engines must be increased as the size of the vessel. Were this true his -conclusion would also be true--namely, that the capacity of a given -vessel regularly to accomplish a given voyage does not increase with the -increase of size, since the consumption of fuel is augmented in about -the same ratio. - -This assumption is directly opposed to the opinion held by Mr. Brunel, -and acted on by him in his recommendations to the Steam-Ship -Company--namely, that while the tonnage of a ship is increased as the -cube of her dimensions, the resistance is increased only about as the -square. - -This question was the main point at issue between Dr. Lardner and Mr. -Brunel; and the proposition which Mr. Brunel then asserted is at the -present time the basis of the calculations which determine the -proportion between the tonnage of a steam-ship and the length of voyage -she has to perform without a relay of fuel. - - * * * * * - -The history of the 'Great Western' steam-ship has been interrupted by -this examination of Dr. Lardner's propositions. The weight at one time -attached to his opinions, the sinister influence they exercised over the -early efforts of those who differed from him, and the great and enduring -importance of the points at issue, have made it necessary to refer to -them at length. - -The ship had been steadily proceeded with, notwithstanding the adverse -criticism of philosophers, and she was launched on July 19, 1837. On -August 18 she left with a tug-boat for London to take her engines on -board, and arrived in the Thames after a passage of four days, -four-fifths of the way under sail. - -When anchored in the river she was crowded with visitors, who, according -to the newspapers of the day, were astonished at 'her magnificent -proportions and stupendous machinery.' - -The engines were at length completed, and received in every detail Mr. -Brunel's constant supervision. - -Extraordinary efforts were made to get the ship back to Bristol and to -start her on her voyage across the Atlantic before the departure of the -'Sirius'--a vessel of about 700 tons and 320 horse-power, bought by the -St. George's Steam Packet Company in order to anticipate the 'Great -Western.' - -At length the 'Great Western' left Blackwall for Bristol, at 6.10 A.M. -on Saturday, March 31, 1838, having on board Captain Claxton, Mr. Guppy, -Mr. Brunel, and many other persons interested in her success. All went -well at first, but at about half-past eight o'clock a very alarming fire -broke out. The felt which covered the boilers had been carried up too -high, and the red lead which fastened it became hot; oil gas was -generated, and it burst into a fearful flame, setting fire to the beams -and under part of the deck. The ship was immediately run ashore on a -mud-bank not far from the Chapman Beacon, while Captain Claxton, Captain -Hosken (the commander), and Mr. Pearne (the chief engineer) endeavoured -to extinguish the fire. - -Captain Claxton went below through the engine-rooms, and forward between -the boilers to the fore-hatch, and in a stifling atmosphere of burning -paint and felt he directed the nozzle of the fire-hose against the -flames. While he was at work, something heavy fell on him from above. On -recovering from the blow, he stooped down, and found the body of a man, -who was lying insensible, with his head covered to the ears with the -water which had collected on the floor. Captain Claxton called for a -rope, and the almost lifeless body was hauled up. It was not till he -went on deck some time afterwards that he learnt that the person who had -fallen on him was Mr. Brunel, and that he had saved the life of his -friend. - -It appeared that Mr. Brunel was going down to Captain Claxton's -assistance by the long ladder which reached from the fore-hatch to the -keelson, and put his foot on a burnt rung. He fell about 18 feet, -striking an iron bar in his descent. Had he not fallen on Captain -Claxton he must have struck the keelson or floor and been killed, and -had not his head been raised at once he would have been suffocated by -the water into which he fell. He was so severely hurt that he could not -move, and he was laid on a sail on deck until the fire was extinguished, -and then lowered into a boat, and landed on Canvy Island, where he -remained some weeks. Although his sufferings were very great, he was -able, within three days of the accident, to dictate a long letter to -Captain Claxton on the state of the ship and engines. - -The fire was soon got under, the ship resumed her voyage to Bristol, and -anchored at Kingroad in the afternoon of Monday, April 2, to the great -surprise of the good people of Bristol, who had heard that she had been -burnt in the Thames. Their astonishment was increased by finding no -outward signs of the disaster; but, as a fact, the deck above the boiler -was charred a fourth of its thickness, and so remained till the ship was -broken up. - -The 'Great Western' started on her first voyage to New York on Sunday, -April 8, at 10 A.M.,[124] and struck soundings off Newfoundland on the -ninth day. She arrived at New York at 2 P.M. on Monday, the 23rd, having -consumed three-fourths of the coal she had taken on board. - -She found that the 'Sirius' had arrived before her; but under all the -circumstances the palm was due to the 'Great Western,' for the 'Sirius' -had left Cork eight hours before the 'Great Western' left Bristol (which -lies a whole day's run further from New York), and had only arrived at -New York in the morning of the day in the afternoon of which the 'Great -Western' came in; and, what is after all the most important point for -comparison, the 'Great Western' had nearly 200 tons of coal left, while -the 'Sirius,' when she dropped her anchor at Sandy Hook, had not only -consumed all her coal, but also all the combustible articles which -could possibly be thrown on the fire, including (to repeat the -well-known anecdote) a child's doll! - -The 'Great Western' was received at New York with well-deserved honour. -According to the journal of one of her passengers, 'Myriads were -collected, boats had gathered round us in countless confusion, flags -were flying, guns were firing, and cheering rose from the shore, the -boats, and all around loudly and gloriously, as though it would never -have done. It was an exciting moment, a moment of triumph.' - -The ship started on her return home on May 7, 1838, with sixty-eight -passengers on board. She made the voyage in fourteen days, although -twenty-four hours were lost by a stoppage at sea. - -After this she ran regularly between Bristol and New York till the end -of 1846. In April 1847 she was sold to the West India Mail Steam Packet -Company, and became one of their best vessels. - - * * * * * - -At length in 1857 she was broken up by Messrs. Castle, of Vauxhall. -Among those who went there to take a farewell of her before she finally -disappeared was Mr. Brunel; thus he saw the last of his famous ship. - - -NOTE (p. 235). - -_Dimensions of the 'Great Western' Steam-Ship._ - - Feet Inch - Length from fore-part of figurehead to after-part - of taffrail 236 0 - Length between the perpendiculars 212 0 - Length of keel 205 0 - Breadth 35 4 - Breadth over paddle-boxes 59 8 - Depth of hold 23 2 - Draught of water 16 8 - Length of engine-room 72 0 - Tonnage by measurement 1,340 tons - Displacement at load draught 2,300 " - -_Dimensions of Engines, &c._ - - Diameter of cylinders 73-1/2 inches - Length of stroke 7 feet - Weight of engines, wheels, &c. 310 tons - Weight of boilers 90 " - Water 20 tons to each boiler 80 " - Diameter of wheel 28 feet 9 inches - Width of floats 10 feet - - - - -CHAPTER IX. - -_STEAM NAVIGATION. THE 'GREAT BRITAIN' STEAM-SHIP._ - -A.D. 1838--1847. AETATIS 33--42. - - - COMMENCEMENT OF THE BUILDING OF THE 'GREAT BRITAIN'--REPORT ON THE - ENGINES (JUNE 13, 1839)--EXPERIMENTS ON THE SCREW PROPELLER--ITS - ADOPTION IN THE 'GREAT BRITAIN'--COMPLETION OF THE SHIP--HER VOYAGE - ACROSS THE ATLANTIC--STRANDING OF THE 'GREAT BRITAIN' IN DUNDRUM - BAY--LETTER TO CAPTAIN CLAXTON ON THE CONDITION OF THE 'GREAT - BRITAIN,' AND ON THE MEANS TO BE ADOPTED FOR SAVING HER (DECEMBER - 10, 1846)--REPORT TO THE DIRECTORS ON THE SAME SUBJECT (DECEMBER - 14, 1846)--APPOINTMENT OF CAPTAIN CLAXTON TO SUPERINTEND THE - EXECUTION OF MR. BRUNEL'S PLANS--LETTER TO CAPTAIN CLAXTON ON THE - DIFFICULTIES TO BE OVERCOME (DECEMBER 29, 1846)--REPORT ENCLOSING - CAPTAIN CLAXTON'S ACCOUNT OF THE ERECTION OF THE BREAKWATER - (FEBRUARY 27, 1847)--REPORT ON THE ARRANGEMENTS FOR FLOATING OFF - THE SHIP (MAY 4, 1847)--SUCCESSFUL ACCOMPLISHMENT OF THE FLOATING - OPERATIONS--SUBSEQUENT HISTORY OF THE 'GREAT BRITAIN'--_NOTE_: - DIMENSIONS OF THE SHIP AND ENGINES. - - -The Directors of the Great Western Steam-Ship Company, encouraged by the -success of the 'Great Western,' determined shortly after her first -return to England to lay down a second ship of not less than 2,000 tons -burden. As they did not at that time contemplate the use of iron, a -portion of the timber was purchased, and drawings were put in hand for a -wooden ship. The proposed vessel was intended to be in all respects a -companion ship to the 'Great Western;' only she was to be of larger -dimensions, as it was found that additional cargo space would be -remunerative. - -In October 1838, Mr. Guppy (one of the Directors) communicated to the -Board the results of some calculations Mr. Brunel had made relative to -the cost and efficiency of iron vessels as compared with wooden ones. -Mr. Brunel then suggested that Captain Claxton and Mr. Patterson, -accompanied by one of his assistants, should make a voyage to Antwerp -and back in the 'Rainbow,' an iron steam-boat of 407 tons burden, and -report on the subject. On receiving their report, which was revised by -Mr. Brunel, and which was strongly in favour of the adoption of iron, -the Directors resolved to build their ship of that material, and of not -less than 2,000 tons measurement, the same size as that which they had -intended for their wooden ship. They also determined to erect the shops, -and provide the tools for building her themselves. - -As in the case of the 'Great Western,' the details of construction were -settled by the Building Committee--Captain Claxton, Mr. Guppy, and Mr. -Brunel--who were assisted by Mr. Patterson. - -The preparation of the design occupied some time. In each succeeding -drawing an increased size was proposed; at length the fifth design, -showing a ship of 3,443 tons burden, was finally approved of. On July -19, 1839, the flat keel plates were laid, and the construction of the -hull was commenced. - -It will be necessary to enter with some detail into the history of the -construction of the engines of the 'Great Britain,' as it has often been -stated that it was on Mr. Brunel's recommendation that the Company built -their own engines. It appears, however, that Mr. Brunel repeatedly urged -upon the Directors the utmost caution and economy, and that they -ultimately acted 'against his suggestion.' - -When the Directors determined, in May 1838, to build a second ship, -they did not entertain any idea of undertaking so great a responsibility -as the manufacture of the engines; nor had they any intention of doing -so, even when, towards the end of the same year, they resolved to build -the ship themselves, and to construct her of iron. - -The dimensions of the proposed paddle engines (for at this date the use -of the screw propeller was not contemplated) were sent, in November -1838, to Messrs. Maudslay and Field, Messrs. Hall, and Messrs. -Seaward.[125] - -Messrs. Maudslay declined to tender, and the negotiations seem to have -fallen through at the time; but they were renewed in April 1839, when -estimates for engines (with cylinders of 100 inches diameter and seven -feet stroke) were again invited from several makers. - -The contest lay eventually between Messrs. Maudslay and Mr. Humphrys -(whose patent for trunk engines was worked by Messrs. Hall). At Mr. -Brunel's desire they prepared designs for engines with cylinders of 120 -inches diameter. He twice induced the Directors to postpone coming to a -decision on the subject, in order that Messrs. Maudslay might mature -their new patent for double-cylinder engines. - -When their tender was placed before the Board, the Directors were of -opinion that it largely exceeded the estimate of Mr. Humphrys. Mr. -Humphrys' estimate, however, had been more than once sent back to him -for revision, at the suggestion of Mr. Brunel, who expressed doubts as -to the possibility of Mr. Humphrys being able to construct his engines -within the sum named by him. - -Messrs. Hall stated that if they tendered for the supply of engines on -Mr. Humphrys' plan, large tools would have to be purchased by them, and -the cost charged on the one pair of engines; they therefore strongly -recommended the Company to become their own engine makers. - -Influenced by these considerations, the Directors determined to adopt -the plan of Mr. Humphrys, and to construct their own engines; and they -appointed him the superintending engineer of their works. - -It appears from a report by the secretary, Captain Claxton, dated March -23, 1840, that 'previous to coming to this decision, Mr. Brunel -succinctly laid before the Directors his views of the matter, and his -opinion of the great responsibility they would incur if they made their -own engines; and doubtless the Directors would have yielded to his -suggestions, but for the report of Mr. Humphrys, showing the utter -hopelessness of getting the engines made piecemeal in Bristol.' - -The following is the report of Mr. Brunel on the subject:-- - - - June 12, 1839. - - At the request of Mr. Maze and Mr. Scott, whom I had the pleasure - of meeting on Saturday last, I send you the following observations - on the two plans and the estimates of Messrs. Maudslay, and of our - Mr. Humphrys. - - I have a copy of Messrs. Maudslay's letter of the 29th ult. - containing their tender, and a subsequent letter of the 11th inst. - in reply to some enquiries of mine respecting their tender and Mr. - Humphrys' estimates, according to which the total cost of a pair of - engines of 110 inches diameter and 8 feet stroke, upon his plan, - and I presume modified as last recommended by Mr. Guppy and myself, - including boilers and fixing on board, would be 29,296_l._, or, as - stated by Captain Claxton in a letter to me of the 1st inst., - 30,700_l._ - - First, as to the comparative merits of the plans, I consider them - both excellently adapted to our particular case, and that the - choice will depend upon other circumstances than the construction - of the engines, and these circumstances, I consider, would be, the - relative cost and the advantages of forming an establishment which - will eventually become necessary for the repair and maintenance of - our engines, contrasted with all the advantages to be derived from - the responsibility and experience in all the details of a - first-rate manufacturer, and to which I attach very great value, - particularly in the early proceedings of a Company like ours. As - regards the cost, I understand Messrs. Maudslay's tender to be for - an engine of four 75-inch cylinders, which is equal to a pair of - ordinary engines of about 106 inches. - - Engine, boiler, and paddle-wheels, fixed on board, supposing the L - vessel in London, and with reduced size of boiler, 41,400 - - Deduct allowance for coal-boxes and combings for hatchways as proposed - by Messrs. Maudslay, 500 - - 40,900 - - Additional expense incurred by Messrs. Maudslay in consequence of - the engines being fixed on board at Bristol instead of London, I - estimate at, 250 - - Total amount to be paid Messrs. Maudslay, 41,150 - - In addition to this will be the freight and insurance, which we are to - pay, and also the unloading at Bristol and placing in the vessel, - which I take at Captain Claxton's estimate, 2,000 - - Making a total of 43,150 - - It is to be observed that this includes Mr. Field's apparatus for - changing water, Kingston's cocks, casing the cylinders, and all - those extras which were applied to the 'Great Western,' and also - the paddle-beams and paddle-wheels. Without these latter the nett - cost of the engine, fixed in place, and including all other extras, - would appear to be about 40,000_l._ or 40,500_l._ If the cylinders - be increased to 77-3/4, which would be equivalent to the pair of 110 - inch, and supposing the cost of the engines to increase in the same - ratio as the power resulting from this increase, but which ought - not to be the case, the total cost, according to Messrs. Maudslay's - estimate, will be 46,500_l._, and deducting the paddle-beams or - framework for carrying the paddles, which do not, I think, form - part of Mr. Humphrys' estimate, probably about 45,500_l._ as - compared with Mr. Humphrys' estimate of 30,700_l._ With respect to - this latter estimate, I cannot help expressing the fears I - entertain that Mr. Humphrys is over-sanguine, and that the cost - would greatly exceed the sum named. The items seem to me to be - moderate prices only for each article named, and I see no allowance - for those alterations, damages, and waste of parts, and a variety - of other contingencies, which in a piece of machinery of this - magnitude and novelty is certain to amount to a very large sum. - - In his estimate of the fittings and smaller parts, I think also he - has greatly underrated them. - - The outlay for tools and tackle would, I think, also be greater - than he seems to anticipate, and on the whole I cannot but come to - the conclusion in my own mind, and I should not act rightly if I - did not communicate that opinion to you, that the first outlay will - be fully as large and probably larger by adopting the plan of - making our own engines than by employing a manufacturer. It is true - we shall have some valuable and costly tools and shops included in - this outlay, and a fine establishment formed, which may be rendered - fully competent in point of means to continue the manufacture of - engines for others, and to keep up the repairs of any number of - engines which the Company are likely to have at work. My only fear - would be that of the risk of the undertaking being too great for a - newly-formed establishment. The making of the vessel itself is no - mean effort, and to superadd the construction of the largest pair - of engines and boilers yet made, and upon a new plan, is - calculating very much upon every effort being successful, and - particularly upon the continued assistance of those who have - hitherto attended to the subject; as it must be well known to the - Directors that if Mr. Guppy, for instance, should be prevented from - giving his time as he has hitherto done, or if Mr. Humphrys should, - from illness or other causes, leave us, the manufactory would be - brought to a stand, and the loss would be serious. I have no wish - to deter the Company from becoming their own manufacturers--I think - it a course which must ultimately be adopted if the Company - thrive--but I should have much preferred that it had been adopted - gradually, that we had commenced with a vessel, and then proceeded - with boilers and repairs; and, as our establishment became formed - and matured, and when we might no longer depend entirely upon the - engineering talents and assistance of one Director, who may be - unable to attend to it, or upon the health of one superintendent - who, as yet, is alone in possession of all our plans and ideas, and - at present is alone capable of carrying them out, we might then - have ventured upon making the engines perhaps for the third vessel. - Circumstances may, however, render it necessary that we should - proceed more expeditiously, and I am only anxious that the - Directors should be aware of the difficulties that we may have to - encounter, and that they should not form expectations as regards - economy in which they may be disappointed. The result of the best - consideration I have been able to give to it is, that the question - does not seem to be one of cost. In that respect, according to my - view, the two modes of proceeding would be nearly balanced, but it - resolves itself into the following question:--Is it better in our - present position to enter at once upon the manufacture of the - engines and boilers, in doing which we shall in part repay the cost - of tools and shops, which must eventually be required, and by which - we shall be more independent, and more capable of expediting the - works, should it become desirable to incur any additional expense - for that purpose, or to throw all the responsibility and risk on - another party or contractor--the vessel, for which we could not - easily contract, being still made in the Company's yard? - - I have thus reduced the question to that state in which I can offer - no further opinion or advice; it is now for you to determine. The - question is one which has frequently to be decided upon by the - Directors of public works; it is very much a matter of feeling, but - it is simplified in the present instance by the circumstance that - the expense in either case will be, to my view at least, about the - same, and the work, I have no doubt, equally good in either case. - - Upon this point, as perhaps upon the subject of cost, I have no - doubt there will be some difference of opinion. It will be said - that the work done under our own superintendence can be more relied - upon than the work of a manufacturer, and that even in the engines - of the 'Great Western' steam-ship, coming from one of the most - experienced manufacturers, many defects may be pointed out. - - I should agree fully with both these arguments, but I think these - advantages are fully counterbalanced by that of the experience in - all the details which is brought into operation in an - old-established manufactory, and the great relief from - responsibility and risk obtained by contracting for the whole work. - -The Directors having determined to make the engines, erected shops and -fitted them up with proper tools. The services rendered to them by Mr. -Brunel at this period were fully acknowledged at the next meeting of the -shareholders.[126] - -Mr. Brunel's attention was now anxiously devoted to the consideration of -the numerous questions involved in the construction of the ship and her -engines; and, in order to obtain reliable information on many points, he -sent one of his assistants, Mr. Berkeley Claxton, in the 'Great -Western.' His sole occupation during six voyages was to note the amount -of rolling and pitching, and the exact performance of her engines, with -the effect of the use of the expansion valves on her speed, and on the -consumption of fuel. These reports furnished Mr. Brunel with information -which was of great value, especially when, shortly afterwards, he -advised the Directors to adopt the screw propeller instead of -paddlewheels. - -The circumstances which led to the adoption of the screw propeller in -the 'Great Britain' instead of paddlewheels were as follows:-- - -In the early part of the year 1840, the performances of the 'Archimedes' -steamer began to attract the attention of scientific men. This vessel, -which was fitted with the screw propeller patented by Mr. Francis -Pettitt Smith, arrived at Bristol in May. A few trips were made up and -down the Float, but the advantages of the screw propeller were not fully -appreciated by those to whom they were explained. - -But Mr. Guppy, who had attended some of these trials, went round in the -ship to Liverpool. On his return he made a report to the Building -Committee, and the Directors, on Mr. Brunel's advice, passed a -resolution delaying the progress of the engines of the 'Great Britain,' -and of those parts of the frame which would be affected by any change of -plans. Mr. Brunel was also requested by them to give his attention to -the question of the adoption of the screw, and to report thereon. - -During the next three months experiments were made by Mr. Brunel, -assisted by Mr. Guppy and Captain Claxton, on the screw propeller in the -'Archimedes.'[127] These experiments afforded ample opportunity of -trying the performances of several forms of screws.[128] - -On October 1, Mr. Brunel attended a special meeting of the Board, and -read and explained a report he had drawn up, in which he laid before the -Directors at great length the results of the different experiments he -had made, and the advantages which he believed would attend the use of -the screw propeller.[129] A resolution was passed adopting it for the -'Great Britain.' - -Mr. Brunel at first thought that he would be able to retain the form of -engines which had been originally determined on for working the paddle -wheels; but, on consideration, this was found impracticable. As the -Company had by this time erected complete engine works, there could now -be no question as to their undertaking the construction of the new -description of engines required for working the screw propeller.[130] - -Mr. Humphrys resigned the post of superintendent of the works, and Mr. -Harman was appointed assistant engineer under Mr. Guppy, to whom the -Directors, on the advice of Mr. Brunel, entrusted the supreme control of -their manufacturing establishment. - -The duties and responsibilities which devolved on the Building -Committee--Captain Claxton, Mr. Guppy, and Mr. Brunel--were most -arduous. To design and construct a steam-ship larger than any that had, -up to that time, been launched, to make this ship of a material which -had but lately been introduced into shipbuilding, and which had never -before been employed on a large scale, to adapt to this ship a novel -form of propeller which had not previously been used save in a merely -experimental steamer, and to build in a newly opened manufactory marine -engines of a much greater size than any that had hitherto been -contemplated, and of a totally different character, was indeed a bold -enterprise. Mr. Brunel had, as has been shown, recommended the Company -not to undertake one part of the work, that, namely, of the manufacture -of the engines, which he thought would have been better entrusted to the -most experienced engine builders. But although the Directors had acted -contrary to his advice, this circumstance in no way diminished the zeal -with which he and his coadjutors entered upon their task. - -A short statement of the principal dimensions of the vessel and engines -is given in a note to this chapter; but some of the more remarkable -features in the design may be mentioned here. - -In the construction of the 'Great Britain,' the same care which had been -spent in securing longitudinal strength in the wooden hull of the 'Great -Western,' was now given to the suitable distribution of the metal. Over -the transverse angle iron ribs at the bottom of the ship were laid ten -deep longitudinal beams (see woodcut, fig. 13, _a_), which, over the -greater part of the bottom of the ship, were covered with an iron deck -(_b_) riveted to their upper edges by angle irons, thus forming a -cellular structure which added greatly to the strength of the ship. It -does not appear that this deck was designed to be watertight, so that it -did not form the same security against accident as the inner skin of -the cellular structure which Mr. Brunel afterwards adopted in the 'Great -Eastern.' - -The upper part of the sides of the ship, in the middle of her length, -were carefully designed so as to give her longitudinal strength. The -side plates were thickened, and were riveted to iron shelf-plates three -feet broad (_c_); and two bands of iron, six inches wide and one inch -thick, with the joints strengthened, ran along the top of the ship's -side. There were bands of iron riveted to the shelf-plate, and iron deck -beams crossed diagonally under the planking of the upper and main decks. -Also at the junction of the ship's side with the shelf-plate there ran -longitudinally a tie of Baltic pine timber, 340 square inches in section -(_d_); this being well secured to the shelf-plate and ribs, added -considerably to the strength of this portion of the hull. - -The ship had five watertight bulkheads, and was thus separated into six -compartments. - -[Illustration: _Scale of feet_. - -Fig. 13. 'Great Britain' Steam-Ship. - -_Transverse Section._] - -She had no keel, as there did not appear to be sufficient advantage -gained by such an appendage to make up for the increase of the ship's -draught by the amount of the depth of the keel. There were two side or -bilge keels (_e_), reaching down to the level of the keel plate of the -ship, so that when grounded in dock she might rest on three points in -her width. - -The 'Great Britain' had what is termed a balanced rudder, a portion of -the rudder (in this case about one third) being in advance of the pivot -on which it turned. The result of this arrangement was that, the -pressures on either side of the pivot nearly balancing one another, -there was no difficulty in putting the helm over rapidly. This rudder -was knocked away when the ship ran ashore at Dundrum, and was -subsequently replaced by an ordinary rudder.[131] - -In the construction of the hull of the ship, instead of a mere imitation -of the arrangements of the timber in wooden ships, the proper -distribution of the material to receive the strains that would come upon -it was carefully considered. In the result, the ship contained, in the -structure of her bottom, bulkheads, deck shelves, and longitudinal -kelsons, the longitudinal principle of construction which Mr. Brunel -afterwards so fully developed in the 'Great Eastern.' - -Apart from their size, the design of the engines of the 'Great Britain' -necessarily presented many peculiarities. The boilers, which were six in -number, were placed touching each other, so as to form one large boiler -about thirty-three feet square, divided by one transverse and two -longitudinal partitions. This boiler, which was fitted in between the -longitudinal bulkheads of the ship, had a double set of furnaces, and -therefore of stoke-holes, one at the fore end, and the other at the -after end, next the engine room. - -It would seem that the boiler was only worked with a pressure of about -eight pounds on the square inch. - -The feed water for the boiler was passed through a casing surrounding -the funnel, in which it was heated before passing into the boiler. This -casing was open at the top, and the water flowed thence into the boiler -by gravitation. A similar arrangement was adopted by Mr. Brunel in the -'Great Eastern.' - -The condensers were made of wrought iron, being in fact part of the -frame of the ship. The main shaft of the engine had a crank at either -end of it, and was made hollow, a stream of water being kept running -through it so as to prevent heating in the bearings. An important point -in the design was the method by which the motion was transmitted from -the engine-shaft to the screw-shaft, for the screw was arranged to go -three revolutions to each revolution of the engines. Where the engines -do not drive the screw directly, this is now universally effected by -means of toothed gearing; but, when the engines of the 'Great Britain' -were made, it was thought that this arrangement would be too jarring and -noisy. After much consideration, chains were used, working round -different-sized drums with notches in them, into which fitted -projections on the chains. The greater part of the length of the -screw-shaft consisted of a hollow wrought-iron boiler-plate tube, the -metal being thus very advantageously placed for taking torsional strain, -and the shaft was in this way made very light. The engines were designed -to work expansively, the steam being cut off at one-sixth of the stroke. - -The completion of the 'Great Britain' was delayed many months, owing to -the financial difficulties in which the Great Western Steam-Ship -Company had become involved; the profit on working the 'Great Western' -having been seriously diminished in consequence of the competition of -the Cunard steamers. - -At length, however, the ship was finished; and she was floated out of -dock into the Floating Harbour on July 19, 1843, in the presence of His -Royal Highness Prince Albert. - -This seems a fitting place to insert the following letter from Mr. -Brunel to Mr. Guppy, written at the beginning of August 1843:-- - - I have been thinking a great deal of your plans for iron-ship - building, and have come to a conclusion which I believe agrees with - your ideas; but I will state mine without reference to yours. At - bottom and at top I would give _longitudinal_ strength and - stiffness, gaining the latter by the former, so that all the metal - used should add to the _longitudinal tie_, while in the neutral - axis and along the sides, and to resist swells from seas, I would - have vertical strength by ribs and shelf-pieces, thus: the black - lines being sections of longitudinal pieces, the dotted lines - vertical and transverse diagonal plates, throwing the metal as much - as possible into the outside bottom plates, and getting the - strength inside by form, that is, depth of beams, &c., the former - being liable to injury from blows, &c., the latter being protected. - - [Illustration: [Fig. 14.]] - - And now for the screw of which I am constantly thinking, and in the - success of which for the 'Great Britain,' remember, I am even more - deeply interested than you. - - If all goes well we shall all gain credit, but '_quod scriptum est - manet_,' if the result disappoint anybody, my written report will - be remembered by everybody, and I shall have to bear the storm--and - all that spite and revenge can do at the Admiralty will be done! - The words 'better sailing qualities than could be given to the - "Polyphemus,"' which I used in my first report to the Admiralty, I - believe have never been forgotten. - - Well, the result of all my anxious thoughts--for I assure you I - feel more anxious about this than about most things I have had to - do with--is first that we must adopt as _a principle not to be - departed from_, that all mechanical difficulties of construction - must give way, must in fact be lost sight of in determining the - most perfect form--if we find that the screw determined upon - _cannot_ be made (but what cannot be done?), then it is quite time - enough to try another form; though even then _my_ rule would be to - try _again_ at making it.... - -The 'Great Britain' was built wider than the locks through which she -would have to pass, as it was supposed that the Dock Company would allow -them to be temporarily widened.[132] - -After a good deal of discussion, negotiations were satisfactorily -concluded, and the requisite alterations were made: the ship passed -through into Cumberland Basin, and the upper lock was restored to its -original state in a few days. - -On December 10, everything was ready for her passing into the Avon -through the lower lock. A steam-tug commenced towing her at high water, -but, before she had moved half her length in the lock, it became evident -to Captain Claxton, who was on board the tug, that there was not an inch -to spare; she was touching the lock walls on either side--in fact, she -had stuck between the copings. Upon this he gave orders to haul her back -again as quickly as possible. This was hardly effected before the tide -began to fall; a few minutes later, and the ship would have remained -jammed in the entrance. - -As the tides had passed their highest, it was necessary immediately to -widen the lock, in order not to lose the spring tide; and this was -accomplished under Mr. Brunel's superintendence, just in time to get the -vessel through that night. - -Mr. Brunel described this occurrence in the following letter, written to -excuse himself from keeping an important engagement in Wales:-- - - - December 11, 1844. - - We have had an unexpected difficulty with the 'Great Britain' this - morning. She stuck in the lock; we _did_ get her back. I have been - hard at work all day altering the masonry of the lock. To night, - our last tide, we have succeeded in getting her through; but, being - dark, we have been obliged to ground her outside, and I confess I - cannot leave her till I see her afloat again, and all clear of her - difficulties. I have, as you will admit, much at stake here, and I - am too anxious about it to leave her. - -The 'Great Britain,' after making several experimental trips, sailed for -London on January 23, 1845, and, although she experienced very severe -weather, made an average speed of 12-1/3 knots an hour. - -The excitement caused by her arrival at Blackwall was very great. -Thousands of persons flocked to see her, and she was honoured by a visit -from Her Majesty and His Royal Highness Prince Albert. - -She left Liverpool on her first voyage on August 26, and arrived at New -York on September 10, having made the passage out in fourteen days and -twenty-one hours. She made her return passage in fifteen days and a -half. - -She started again in October, taking sixteen days and a half across. On -her homeward passage, she broke her screw, and got home under canvas -after eighteen days of rough weather which fully tested her sailing -qualities. - -The experience of these voyages showed that the supply of steam from the -boilers was defective; the necessary alterations were carried out -during the winter months, and the ship was fitted with a new screw. - -In the beginning of 1846, everything seemed to promise well for the -success of the 'Great Britain.' She started on May 9, with her full -complement of passengers and cargo, but again an accident happened, -which prevented this passage from affording a trial of her steaming -power. On May 13, the guard of the after air-pump broke; but up to that -time her speed had averaged eleven and three-quarters knots. - -She returned from New York in thirteen days and six hours, against -adverse winds for ten days, with a speed varying from eight and a half -to twelve knots. On one day of her voyage, June 13, she ran 330 knots in -the twenty-four hours, or nearly sixteen statute miles an hour. This was -said to have been the quickest passage which had, up to that time, been -made under similar circumstances of wind and weather. - -She left Liverpool again at the beginning of July, and arrived at New -York in thirteen days and eight hours, or, deducting stoppages, in -twelve days and eleven hours--the shortest passage then and for some -time afterwards recorded. Her homeward passage was accomplished in -thirteen days, including a stoppage of eighteen hours to repair the -driving chains which had been damaged. - -She started again from Liverpool on her outward voyage on the morning of -September 22, 1846, having on board 180 passengers (a larger number than -had ever before started to cross the Atlantic in a steamer), and a -considerable quantity of freight. A few hours after her departure, and -at a time when it was supposed that she was rounding the Isle of Man, -the ship ran ashore, and all immediate efforts to get her off were -unavailing. When daylight came, the captain found, to his surprise, -that she was in Dundrum Bay, on the north-east coast of Ireland. The -passengers were landed safely when the tide ebbed. - -Captain Claxton, the managing Director of the Company, went at once to -the ship. He found her lying at the bottom of a deep and extensive bay; -the ground on which she rested had an upper surface of sand, but -underneath this were numerous detached rocks. The ship had settled down -upon two of them, and had knocked holes in her bottom. Her head lay NW., -leaving her stern and port quarter exposed to a heavy sea, which, at -Dundrum, always accompanies southerly gales. - -When Captain Claxton got to the ship, he made arrangements for trying to -get her off at the next spring tides, which were on the following Monday -(September 28); but on the Sunday, a gale of wind from the southward -sprung up, and at the night flood-tide the water broke over her; nothing -remained to be done but to drive the ship higher up the beach into a -position of greater safety. Sails were therefore set, and she was driven -forward a considerable distance. - -Mr. Patterson was sent by the Directors to Dundrum with Mr. Alexander -Bremner (who had had considerable experience in floating stranded -ships), and they endeavoured to protect the vessel by breakwaters. -These, however, were soon carried away; and, after this misfortune, the -Directors seem for a time to have lost all hope of saving their ship. - -On December 8, when the immediate pressure of Parliamentary work was -over, Mr. Brunel went to Dundrum, having some time before been requested -by the Directors and underwriters to examine and report on the ship. He -was delighted, he said, in spite of all the discouraging accounts he had -received, to find the 'Great Britain' 'almost as sound as the day she -was launched, and ten times stronger and sounder in character,' though -at the same time he was grieved to see her 'lying unprotected, deserted, -and abandoned.' - -Whatever may have been the misgivings of others, he felt no doubt as to -the possibility of saving the ship, by at once protecting her by a -breakwater made of fagots; and before he left Dundrum he set Captain -Hosken at work at the new arrangements, and he guaranteed the immediate -expense in the event of the Directors not sanctioning the measure. - -Immediately on his return to town, he wrote the following somewhat -vigorous letter to Captain Claxton:-- - - - December 10, 1846. - - I have returned from Dundrum with very mixed feelings of - satisfaction and pain, almost amounting to anger, with whom I don't - know. I was delighted to find our fine ship, in spite of all the - discouraging accounts received, even from you, almost as sound as - the day she was launched, and ten times stronger and sounder in - character. I was grieved to see this fine ship lying unprotected, - deserted and abandoned by all those who ought to know her value, - and ought to have protected her, instead of being humbugged by - schemers and underwriters. Don't let me be understood as wishing to - read a lecture to our Directors; but the result, whoever is to - blame, is, at least in my opinion, that the finest ship in the - world, in excellent condition, such that 4,000_l._ or 5,000_l._ - would repair all the damage done, has been left, and is lying, like - a useless saucepan kicking about on the most exposed shore that you - can imagine, with no more effort or skill applied to protect the - property than the said saucepan would have received on the beach at - Brighton. Does the ship belong to the Company? For protection, if - not for removal, is the Company free to act without the - underwriters? If we are in this position, and if we have ordinary - luck from storms for the next three weeks, I have little or no - anxiety about the ship; but if the Company is not free to act as - they like in protecting her, and in preventing our property being - thrown away by trusting to schemers, then please write off - immediately to Hosken to stop his proceeding with my plans, because - I took the pecuniary responsibility of the cost of what I ordered - until he could hear from you, and of course I do not want to incur - useless expense, but still more I do not wish any proceeding taken - as from me to be afterwards stopped. I will now describe as nearly - as I can what I have seen, and what I think. - - As to the state of the ship, she is as straight and as sound as she - ever was, as a whole. She is resting and working upon rocks, which - have broken in at several places, and forced up perhaps 12 to 18 - inches many parts of the bottom, from the fore stoke-hole to about - the centre of the engines, lifting the boilers about 15 inches and - the condenser of the fore engine about 6 or 8 inches; the - after-condenser, perhaps, half an inch. The lifting of the - fore-condenser has broken that air-pump, the connecting rod having - been unwisely left in, and the crank being at the bottom of the - stroke. Of course the air-pump could not help being broken; except - this, the whole vessel, machinery, &c., are perfect. I told you - that Hosken's drawing was a proof, to my eye, that the ship was not - broken: the first glimpse of her satisfied me that all the part - above her 5 or 6 feet water line is as true as ever. It is - beautiful to look at, and really how she can be talked of in the - way she has been, even by you, I cannot understand. It is - positively cruel; it would be like talking away the character of a - young woman without any grounds whatever. - - The ship is perfect, except that at one part the bottom is much - bruised, and knocked in holes in several places. But even within - three feet of the damaged part there is no strain or injury - whatever. I think it very likely that she may have started leaks - where she has been pounding away upon the rocks, but nothing more; - and as I said before, all above her 5 or 6 feet water line is - uninjured, except her overhanging stern; there is some slight - damage to this, not otherwise important than as pointing out the - necessity of some precautions if she is to be saved. I say 'if,' - for really when I saw a vessel still in perfect condition left to - the tender mercies of an awfully exposed shore for weeks, while a - parcel of quacks are amusing you with schemes for getting her off, - she in the meantime being left to go to pieces, I could hardly help - feeling as if her own parents and guardians meant her to die there. - - Why, no man in his senses can dream of calculating upon less than - three months for the execution of any rational scheme of getting - her off; and no man in his senses, I should think, would dream of - taking her across the channel in the winter months, even if he had - got the camels or floats fast. Of this I don't feel so competent to - form an opinion, though I think I can judge, and I should consider - it a wanton throwing away of my shares if the Directors allowed - her to be taken out, even if afloat; but at all events I am - competent to judge of the probable time occupied in getting means - to float her, and I maintain that it would be absurd to calculate - upon less than two or three months. It is not therefore the mode of - getting her off that we ought to have been all this time thinking - of, but how to keep her where she is. I feel so strongly on this - point that I feel quite angry. What are we doing? What are we - wasting precious time about? The steed is being quietly stolen - while we are discussing the relative merits of a Bramah or a - Chubb's lock to be put on at some future time! It is really - shocking. - - Having expended a little of my feeling, I will tell you what I have - done, and what I should recommend. - - First, instantly to disconnect the engines and air-pumps, and - remove all the working gear, so at least to leave the mischief to - the lower part. By the bye, the cylinders are not disturbed or hurt - in any way at present, but with the engines exactly at the bottom - of the stroke, and the connecting rods on, it is a wonder they are - not. If the air-pump had been disconnected it would not have been - broken. I have taken upon myself to order this. - - Secondly, I suggested to Hosken, in which he quite agreed with me, - to take off all strain from her extreme stern. At present she has - cables out from this prodigious mass overhanging nearly 30 feet - from any part capable of bearing the strain. - - I recommend his taking the chain cables through the ship's side, - and making them fast with a spar or timber outside the starboard - side, about as far forward as the capstan. At present she is canted - seaward. - - I thought she was better so than presenting the hollow lines of her - quarter to the sea, and both Hosken and Bremner came round to my - opinion. - - Thirdly, there is a stream of water which now washes away the sand - from her bottom. I think it essential this should be diverted, and - kept so. - - Fourthly, my plan for protecting her is totally different from any - that have been proposed, and if we have not such excessively bad - weather as would prevent anything being done, I believe it may - easily be done. And if done will, I am convinced, be perfectly - good; while any solid timbering, even if made, would, I think, be - most likely the cause itself of tremendous damage, if once beat by - the sea. I will only premise by saying that both Hosken and - Bremner came to the conclusion that it was the best thing that - could be done. - - I should stack a mass of large strong fagots lashed together, - skewered together with iron rods, weighted down with iron, - sandbags, &c., wrapping the whole round with chains, just like a - huge poultice under her quarters, round under her stern, and half - way up her length on the sea side. - - The detail of the mode, and the precautions of detail, I have not - time now to describe. I am as certain as I can be of anything that, - once made, such a mass of fagots would stand any sea for the next - six months, and the chances of making it (after one or two - failures, no doubt) are so good, that if properly taken in hand, I - look upon it as certain. I will write more fully to-morrow--in the - meantime I have ordered the fagots to be begun delivering. I went - myself with Hosken to Lord Roden's agent about it, and I hope they - are already beginning to deliver them. Write and stop them or - not--if not, of course my responsibility ceases. I will write again - to-morrow, but let me know by train how we stand with the - underwriters. - -This letter was a few days later supplemented by the following formal -report to the Directors, which was printed and circulated amongst the -proprietors. - - - December 14, 1846. - - According to your request I have, as soon as my engagements would - allow of my leaving London, paid a visit to the 'Great Britain,' - and I now beg to report to you the state in which I found the - vessel, and my opinion of the best means to be taken for recovering - the largest possible amount of the property invested in her. If I - state these opinions concisely, and without any qualifications, you - will not suppose that I have the presumption to think them - infallible, but merely that I am compelled, by the shortness of the - time left me to write to you, to avoid all circumlocution, and to - give you as simply and briefly as possible the opinions I have - formed--at the same time I am bound to say that I have not formed - them hastily, and that my convictions upon the several points upon - which I may express my feelings are very strong. - - First, as regards the present state of the vessel, I was agreeably - disappointed, after the reports that had reached me, to find her as - a whole, and, independently of the mere local damages of which I - will speak presently, perfectly sound, and as strong and as - perfect in form as on the day she was launched. - - In receiving this statement you must bear in mind the great - difference between an iron vessel and a timber-built ship. In the - former, parts may be considerably damaged or even destroyed, and - the remainder may not only be untouched, but may be left unstrained - and uninjured. In a timber ship this can hardly be the case; if any - considerable portion of a ship's bottom is stove in, the timbers or - ribs completely across the ship and the planking longitudinally, - cannot fail to be strained to a very considerable distance in both - directions. You must therefore remove from your minds all - impressions derived from your experience of damages sustained by - timber-built ships in order to understand my statement, which is - strictly correct:--that, except the parts actually damaged, the - extent of which is comparatively small, the ship is perfectly - sound, and as good as at the hour when she struck. This soundness - and freedom from any damage extends from about the 5 feet water - line to the top (with the exception of the injury sustained by the - knocking away of the rudder post and a blow under the stern); - nearly the whole of the vessel is therefore sound: the principal - injury is in her bottom under the boilers and engines. The vessel - has evidently been thumping upon the rocks, and almost entirely - upon this part of the bottom from the first few days after she - grounded; and at present in all probability her whole weight is - resting upon this part; yet notwithstanding this she is perfectly - straight, and has not broken nor even sprung an inch in the whole - length. The boilers have been forced up about 15 inches, and one of - the condensers has been lifted about 8 inches, breaking the - air-pump. At present this is nearly the extent of the damage done; - all of which could easily be repaired if the vessel were in dock. - - I will now state my opinion of the best means of recovering the - largest possible amount of the property which has been invested in - her. In this view I can only imagine two alternatives--the one to - break her up on the spot and make the most of the materials; the - other to get her afloat and into port, and restore her into good - condition, or sell her to those who would so restore her. - - The first alternative may I think be discarded at once; the plates - and ribs of an iron vessel are difficult enough to convert into - useful materials for any other purposes, even in the midst of - workshops and with tools and appliances at hand. In such a place as - Dundrum Bay I do not believe the materials would pay the expense of - cutting up; the masts, spars, chains, &c., in fact the stores and - perhaps a few of the lighter part of the engines, might repay the - cost of removal, but the whole would certainly not amount to many - thousands; probably hundreds would be a safer estimate of the - amount to be realised clear of all expenses. To remove the vessel - and take her into port, and either restore her or sell her, is then - the only means of recovering any part of the whole of the capital - invested in this ship. If she is so brought into port she may be - worth, unrepaired, 40,000_l._, 50,000_l._, or 60,000_l._, according - to the opportunities that may offer themselves of employing her - usefully or selling her. The only question is, then, how at the - least expense, and at the smallest risk, is the vessel to be got - into port? But, as I will now endeavour to prove to you, the mode - of getting the vessel off the shore and into port is again quite - secondary to the consideration of how to preserve her where she is - so that she may be in a condition to be removed, _and to be worth - removing_, when the means of doing this are ready, and the proper - time is arrived for attempting it. - - In the first place I assert unhesitatingly, that no man in his - senses and who thoroughly understands the circumstances of the - case, the weight and position of the vessel, the amount of the rise - and fall of the tide, and the draught of water around her, and the - extraordinarily exposed situation, would dream of calculating upon - completing the requisite means for floating her under three months. - - _In the meantime the ship must be protected._ Even if it were - practicable to construct the necessary apparatus, and to float the - vessel to-morrow, it would be little short of madness to go to sea - with her at this time of the year; but I am doing wrong to discuss - a case which cannot arise. The vessel cannot, according to any - rational calculation of chances, be got off under three months, and - it is equally against all probability that, if left unprotected, - there would be anything worth taking off at that time. It is - useless, therefore, at this moment discussing the best mode of - floating the vessel; and I think, under such circumstances, it - would be most unwise hastily to determine upon any plan. The first - thing is to know whether there are any means of preserving the - vessel, and whether any such plans can be carried into effect at - some reasonable cost, which it may be worth incurring. I have - looked at the vessel, and considered the very exposed situation in - which she is placed (and a more exposed one could hardly be found), - and I am convinced that no fixed breakwater of ordinary - construction could be made at any reasonable expense, or in time to - prevent mischief. There is no depth of sand into which to drive - piles, and the rock is too uneven and broken to allow of any - framing being constructed and secured to it; and any framework - would be liable to be destroyed during the progress of its - construction, as that already attempted has been, and the timber - might be the cause of serious damage to the ship. The plan I should - recommend would at least be free from these objections, would be - comparatively inexpensive, and I am firmly convinced would be - perfectly effectual as a protection. At the same time few persons - who have not seen the effect of a sea beating against fagots will - share in that conviction; what I recommend is, to form under the - stern and along the exposed side of the vessel a mass of fagots - made of strong and long sticks, and used in the manner which has - been so successfully practised in Holland and elsewhere, for the - repair and protection of banks against the sea. The fagots should - be packed closely, and for a considerable thickness against the - ship's side and up to the level of the decks, and secured with rods - run vertically through the mass, and chains laid horizontally and - binding the whole tightly to the ship. The heaviest sea has no - effect upon such a mass, and I believe the vessel would remain as - uninjured and indeed as unaffected by the sea as if in dock; 8,000 - or 10,000 fagots, 300 or 400 fathoms of 1 inch or 3/4 inch - second-hand chain cable, none of which need be lost, 300 or 400 3/4 - inch rods sharpened at the ends, 1,000 bags to fill with sand, with - what stores you have on board, would suffice; and, if next coming - springs and the gales which have hitherto accompanied them are - safely passed, I cannot foresee any difficulty whatever in the way - of completing the protection I propose. Of course, in all works - dependent upon wind, weather, and tides, certainty cannot be - obtained; but of one thing I am quite certain, that no other plan - offers the same chance of success, or at so small a cost. I have - communicated to Captain Claxton the steps which I took, in - conjunction with Captain Hosken, for procuring the fagots before I - left Dundrum; I have also communicated to him the directions which - I gave with respect to the engines, &c., and it is unnecessary - therefore that I should repeat them. I will only recapitulate in a - few words the substance of the advice I have above given, and of my - reasoning. You have a valuable piece of property lying on a most - exposed shore; if preserved for a few months that property will in - all probability be worth 40,000_l._ or 50,000_l._; if neglected for - a few weeks longer it will probably be worth nothing. Can you, as - men of business, under such circumstances, waste your time at this - moment in discussing what you will do in three months hence, and - what plan you will then adopt to take your property to market, but - will you not rather first and immediately adopt decisive steps for - preserving that property, and then consider what you had best do - with it? - - I have no wish to escape the responsibility of advising you, as you - request me to do so, as to my opinion of the best plan to be - adopted hereafter for removing the ship; but adhering to the - principle that I have laid down, I should decline to do so at - present, did I not see reason to fear that you might be losing time - and money by relying upon expectations which I am convinced would - be disappointed. I would strongly urge upon you not to place your - reliance upon any plan which depends upon floating the vessel by - camels, and taking her to sea unrepaired, and therefore entirely - dependent upon those camels. The immense breadth of these floating - camels, and the risk of taking such an unmanageable floating - ill-connected mass to sea, cannot have been correctly or - sufficiently estimated; and the certainty of the whole going to the - bottom, in the event of even a very moderate gale of wind or a - slight swell, has been apparently quite lost sight of. I am also of - opinion that the difficulty of lifting the vessel at all by - auxiliary floats has been underrated. The vessel has worked herself - about 5 or 6 feet into the solid rock and sand, and may very - probably get a little deeper before the time for lifting arrives. - She must therefore be lifted, say at least 4 feet to 4 feet 6 - inches, before she could be got out of the dock she has made; and - the floating power must therefore be calculated at least to raise - her 5 feet 6 inches, so as to be quite sure of moving her. Now - there is not more than 10 feet water around the vessel even at high - water of ordinary springs, and it would be impossible to calculate - upon more than 9 feet as a certainty. No floating power worth - having can be got in the vessel, and the floating vessels must - therefore be capable of sustaining the whole weight, with a draught - when the vessel is lifted of only about 4 feet. The weight to be - sustained is 2,000 tons, and to do this with vessels drawing only 4 - feet would require that they should be upwards of 30 feet in - breadth on each side, forming with the ship a total width of - upwards of 100 to 120 feet, and upwards of 300 feet in length. I do - not say that this operation is impracticable, but it is at least a - very difficult one, and must be almost entirely dependent upon - weather, and, unless in perfectly smooth water, a very hazardous - one. My belief and conviction is that the safe mode of proceeding, - and by far the cheapest, will be to lift the vessel by mechanical - means, to lay ways under her, and to haul her up sufficiently far - for her to be safe from the sea; to repair her just sufficiently to - make her water-tight, then launch and bring her to Liverpool or - Bristol. But, as I have before stated, there is time to consider - these points, if in the meantime we take steps to preserve the - ship. If the property is not even now worth protecting, it will - indeed be waste of money to be preparing at some considerable - expense to remove what will in all probability be only then a - valueless carcase. - - If the Directors should determine upon adopting the course I have - recommended, I must remind them that the plan is one depending - entirely on the skill, the vigour, the aptitude for expedients, and - possibly, if bad weather should come on, and day after day the work - be destroyed, on the unwearying perseverance and determined - confidence in the plan of the person directing it, and the - sufficiency of means at his command. - - I cannot conclude without doing justice to Mr. Bremner, whom I met - on board, and acknowledging the friendly and liberal manner in - which he discussed the various means to be adopted, and assisted me - with his valuable advice; and, although I may have somewhat - differed with him as to the advisability of attempting to float the - vessel away to sea without first repairing her, yet upon most - points we were perfectly agreed; and I firmly believe that if any - man could take her off (and if it would be prudent to let him do - so), Mr. Bremner's great experience and sound practical knowledge - and good sense in devising any plan, and his energy and skill in - carrying it out, would ensure every chance of success which the - circumstances admit of.[133] - -The Directors adopted Mr. Brunel's suggestions; and, at his urgent -request, they appointed Captain Claxton to superintend the execution of -his plans. - -Captain Claxton thereupon went to Dundrum, where he took sole charge of -all the subsequent operations. - -The following is selected from the many letters written by Mr. Brunel to -Captain Claxton at this time. - - - December 29, 1846. - - You have failed, I think, in sinking and keeping down the fagots - from that which causes nine-tenths of all failures in this world, - from not doing quite enough. Two and a half hundredweight of - sandbags, weighing barely one hundredweight [_in water_], would not - of course keep quiet a large fagot of five bundles, and two and a - half hundredweight of fire-bars, I should think, would only barely - do. The load must always be excessive, to make sure of a thing.... - I would only impress upon you one principle of action which I have - always found very successful, which is to stick obstinately to one - plan (until I believe it wrong), and to devote all my scheming to - that one plan, and, on the same principle, to stick to one method, - and push that to the utmost limits before I allow myself to wander - into others; in fact, to use a simile, to stick to the one point of - attack, however defended, and if the force first brought up is not - sufficient, to bring ten times as much; but never to try back upon - another point in the hope of finding it easier. So with the - fagots--if a six-bundle fagot wont reach out of water, try a - twenty-bundle one; if hundredweights wont keep it down, try tons. - -The able manner in which Captain Claxton carried out Mr. Brunel's plans, -and suggested important modifications of them, is acknowledged by Mr. -Brunel, in a report to the Directors, written after the successful -completion of the breakwater. - - - February 27, 1847. - - I beg to enclose Captain Claxton's account of the proceedings at - Dundrum Bay during the time that he has been engaged in forming the - breakwater or protection to the ship in the manner recommended by - me. - - Notwithstanding the great difficulties he has had to contend with - from almost incessant bad weather, with the wind blowing dead on - shore nearly the whole of the month of January, and consequently - preventing the tides from ebbing sufficiently out to allow of the - work being properly proceeded with, and notwithstanding the - occurrence of more than one storm at the most critical period of - the work, he has, as I fully relied upon his doing, succeeded in so - far protecting the ship, that she has been comparatively unaffected - by violent seas, which, there is no doubt whatever, would otherwise - have seriously damaged her. We may now calculate with tolerable - certainty upon preserving her without further injury until the - finer or at least more settled weather sets in. - - In the work which Captain Claxton undertook, and has so - successfully completed, he has been compelled to vary very - materially the mode of proceeding first laid down; he has, in fact, - been obliged to adapt his plans to his means of execution, and - almost from day to day to devise modes of proceeding with only the - experience of the past day to guide him. Numerous unforeseen - difficulties have occurred, upon which he kept me daily informed; - and simple as my plan might have appeared to others, it required - much skill, contrivance, and unwearying perseverance to carry out - so many alterations and improvements as it progressed. I had relied - confidently on success when my friend Captain Claxton undertook the - work, and the result has fully confirmed my expectations. - - It is now necessary to turn our attention to the best mode of - removing the ship. I hope in about a fortnight from the present - time to be able to give you some opinion upon this point, but it is - one requiring much consideration; and until I had the opportunity - of conferring with Captain Claxton on the subject, and also had - before me all the measurements and data which he has collected, it - was useless to attempt it. - - * * * * * - -The construction of the breakwater will be understood by the following -extracts from a report made by Captain Claxton to the Admiralty. - - - 'Great Britain,' July 16, 1847. - - ...Mr. Brunel's instructions to me were principally by word of - mouth; the difficulty to be got over, in his opinion, being the - foundation upon sand, varying in depth according to the points or - hollow of a substratum of rock, and according to the quarter from - which the wind blew. - - The foundation could only be made at low water, and as fast as a - layer of fagots was laid, it was rapidly pinned down with iron - rods, bent at the heads, varying from 9 to 6 feet in length, and - driven to the rock under, loaded with stones quarried from the - nearest reefs, and upon these, the last thing as the flood came in, - chain cables, air-pump covers, fire-bars in large bundles, and the - ship's guns were dropped, care being always taken to have the ends - of the chains, and the slings of other heavy matters, fast to the - ship. As the tide in smooth water began to recede, or in heavy seas - began to lose effect in striking, these iron weights were lifted, - and the fagots which were ready were ... placed; and the same - process followed tide after tide when the water ebbed sufficiently, - which upon the neaps it never did at all, and upon the springs it - only did for about an hour, unless there was either no wind at all, - or unless the wind blew off the land, or from the West round by the - North to ESE. It is necessary, to a proper understanding of the - nature of this really large work, to describe a bundle of fagots, - lest an idea should be formed that it is a small thing and easily - handled. They averaged 11 feet in length, and 5 feet in - circumference near the butts, which all pointed one way. When tied - in Lord Roden's wood, many were 13 feet long, and none were taken - under 10 feet. A cart of the country with one horse could carry - about ten bundles when well lashed, and as they came down there was - rarely more than the head of the horse to be seen. Sixpence per - bundle, and sixpence for delivery, was the contract; the distance - at high water nine miles, at low water six miles; and our sailors - made them into large bundles of twos, threes, and fours; now and - then we experimented with bundles of eight or even ten, in the - middle of which were bags of sand (old guano bags), varying in - number, of 2 cwt. each, and sometimes as many as amounted to a ton - in weight. These large bundles stood if the water remained smooth; - but if, before we could build up to their height with smaller - bundles, and, as it were, prop or shoulder them fore and aft, we - were caught by a breeze and sea, we found them rolled up to high - water mark, or on spring tides four hundred yards; while some are - now being hove out of the sand entire, and with the sand bags and - sand complete.... - - Having got the foundation, on which, I may mention, we placed one - of the ship's iron life-boats, 30 feet long, 8 feet wide, and 5 - feet deep, and loaded her with stones, and which also, although - over bundles of fagots, went bodily down, until only the gunwale - was above the level of the strand, we began to build the part which - was to save the ship from the blows of the sea, and which I was - instructed by Mr. Brunel to bring up to a point to the ship's - gunwale in the form of a large poultice, occupying the whole space - under her counter, the whole of the exposed quarter (the port - quarter), and inclining inwards from the outside, and declining - from the top to the same point forward, to the after end of the - bilge keel. I was to be, and was, as careful as I could be to - secure as well as to weight down as we built. Chains were secured - in many places to the lower bundles of fire-bars sunk in the sand - outside all, and these were brought into the arms of the screw, and - to ring bolts let into the ship; and rarely were two layers placed - without a repetition of the securing and weighting process all the - while we had chains to use.... - - We were frequently beaten; whole masses were capsized, but it was - found that even the foundation broke the ground swell, which, - instead of having a fair run as it has over the strand, seemed - stopped, and to break differently; and certainly the ship was daily - eased of the blows of the sea.... Finding the wind keeping on - shore, the fagots we placed shrinking, sinking, or settling down, - and, notwithstanding the weights and lashings, commonly breaking - away, I proposed to try spars. Mr. Brunel acceded, and recommended - my trying four long ones, to the heels of which were to be attached - chains with a spread of eight feet, the spars being pointed at the - heels, the slack of the chains, and the height at which they were - stopped to the spars, being intended to be sufficient to embrace - about a dozen bundles of fagots, the points of the spars sticking - through the foundation below the level of the sand. After placing - the first pair of spars at an angle from the gunwale of about 70 - degrees, and before the second pair with its fagots could be got in - place, and after heaving them down tight with a tackle to each from - the head to the gunwale, a heavy sea came with the flood dead on, - and although the spars were seven inches square, they stood the - blows of the sea, bending in the middle full five feet when heavily - struck. This gave me the idea of green trees: firs being the first - that occurred to me; first because of their height, and next - because in Lord Downshire's grounds at Dundrum the castle wood - consisted of them only, and lastly, because they were cheap and at - hand. The spars we fortunately placed, and which stood so well, - were American elm, a large balk of which had been sawed in four - lengths of 42 feet for framing, for Mr. Bremner's breakwater.... - The lengths required to allow the application of a tackle to the - head to heave them tight down to the gunwale, or to the - scuttle-holes of the ship, were from 45 to 50 feet. I found that - the firs of this length were scarce, and too fine at the head; but - on looking in Lord Roden's wood, a better substitute was offered in - the form of beech trees of any size, and a contract was speedily - made, and as speedily completed; the carts of the country bringing - in one tree at a time, until about eighty were placed at the most - exposed point, the quarter, in three rows, the outside row at an - angle of 45 degrees. Beech-trees were found decidedly better than - firs, or, I believe, than any other description of tree, as their - weight was soon found sufficient to keep them in place without the - heaving down tackles. They can be got of great length, without - being so large and (carting, pointing, and handling considered) so - unwieldy a butt as firs, and they are of greater diameter aloft, - consequently stronger, and altogether tougher than firs. Having got - the whole stern surrounded, and having continued them at from 4 to - 5 feet apart up to the bilge keel, or about 80 feet of the ship - from the screw, I applied smaller spars (easily and economically - obtained from the Tyrella domain, or within half a mile of the - ship) laterally and diagonally, and about a foot apart in the - former case, and 3 or 4 feet in the latter; the number about 300, - of all or any lengths between 15 and 30 feet. While this was about, - the fagot process was going on; and before that was completed, I - found the foundation with the boat, and its 40 tons of stones, and - even the spars, although pointed at the angles, indicated an - inclination to move forward through the sheer force of the rollers. - To check this, tackles were made fast to three warps out to - seaward, with two anchors to each, and brought to the spars with - four spans to the inner block. Thus twelve of the largest spars - were grappled, the falls taken on board, and all hove tight; the - whole of the spars having first been attached to one another by a - round turn of a half-inch chain with strong staples, and of course - by the lateral spars or spreaders, and their innumerable seizings. - Suffice it to say, as regards the spars, that when struck by - violent seas from half-flood to half-ebb, they bend in a body from - 3 to 4 feet, and spring back after the blow; and this is, I - believe, the whole secret of the efficiency of the spar part of the - breakwater, which has stood the whole winter, only one having - broken, and that because the head took against the topsail yard, - lashed along stanchions of the rails as a hold-down for the tackles - attached to their heads. As a proof that this is the probable cause - of its standing so well, I may refer to Mr. Bremner's breakwater, - which went with the first heavy gale and sea, although made of - balks of from 17 inches to 13 inches thick: also to our having - ourselves placed a pine spar 9 inches diameter down by the side of - the outside tree on the starboard quarter, and which broke in two - right in the middle with the first sea that struck it. The sea - struck very hard against the spars and framework, from which it was - received by the fagots without any shock to the ship worth speaking - of. With respect to the fagots, I could not find materials to go on - weighting down as we went on piling up.... I therefore ran the - remaining fagots up light. No sooner, however, was this done, and a - gale came on, than we were compelled to let go the lashings, and to - help some of the top ones to escape, as the whole of the unloaded - body rose and fell full three feet with the sea, and would have - done mischief to the spars and to the ship, by shouldering her - quarter, and twisting her. About 200 bundles broke away in this - gale. They were, however, all recovered, and placed further forward - and low down, and then loaded with stones; about one third of the - top space having after this been left open, or one third down from - the apex levelled. Shrinkage did much towards this, and breaking - in pieces a good deal; so it was not deemed advisable to fill that - space again. - - About the 1st of May the progress made in lifting the ship by - tightening her from the inside, and by lightening her of everything - moveable, led me to believe that we should be about getting her off - towards the end of this month. I therefore felt that it was time to - begin removing the fagot portion of the breakwater.... The process - of levelling went on for about three weeks, when all above the - loaded portion was taken away. We commenced on that portion from - necessity, and found that by no contrivance of purchases and levers - could our ten men get up or out more than four or five bundles per - tide. This became, and even now is, a serious matter. We have got - up all our chains and weights, and nothing remains but the fagots - and stones, which are so embedded in sand as to form a mass which - is more difficult to move than granite rock would be, as we cannot - blast. Twenty labourers have been twenty-one tides at work, by - contract, and certainly they have made an impression; but it is not - lowered over two feet. The lower portion was made of furze bundles, - here called whins, and they are great collectors of sand, and only - come up at all by being cut to pieces. I mention this to show that - furze and fagots loaded with stones on sand 500 yards from - high-water mark, exposed to the sea, will form a foundation on - which a building of any weight might be erected.... - - Mr. Brunel informed me, when I undertook to carry out his views, - that there was nothing new in using fagots to stop breaches in - sea-walls, as in Holland; and that he saw no reason why they should - not stop the force of the sea in protecting ships as well, provided - they could be secured, and a foundation got. They were to be made - of alders, ash, holly, laurel, oak, or anything tough, to be cut - down, and made up green, to be placed with all their leaves on, to - be pointed to the sea at their butts; and inside the walls of them, - if I may so speak, whin (furze) bundles were to be weighted down, - the fagots placed in steps or rows of about 4 feet from the outside - to the ship's gunwale. - - * * * * * - -As the summer came on, the mode of lifting and floating the ship had to -be decided. On this point Mr. Brunel wrote to the Directors:-- - - - May 4, 1847. - - You have heard from time to time from Captain Claxton of the result - of the means adopted by him for protecting the 'Great Britain' from - the effects of the sea, and which, I am happy to say, have been - quite successful; and you will have heard also generally from him - of the steps which we have since taken, preparatory to getting off - the ship. - - I will now explain to you the object I have kept in view in these - preparations, and the course I should now advise you to follow. - - After completing the works for the protection of the ship, and - before determining upon any mode to be recommended to you for - getting her off, I thought it would be desirable to lighten her of - all that could be easily removed, and to ascertain how much of the - vessel could be made water-tight, and what extent of buoyancy could - be obtained in the vessel herself, as, in my opinion, upon our - success in this would depend altogether the practicability of - lifting the ship by camels. If no great extent of buoyancy could - have been obtained, I should certainly have recommended lifting the - vessel by mechanical means, as I do not consider that, with the - draft of water which could be calculated upon around her on - ordinary tides, sufficient floating power by camels could be - obtained in an easy practicable manner. It was also quite possible - that we might succeed in making the vessel alone sufficiently - buoyant to lift high enough on the spring tides; and by shifting - her position, or by other means, to maintain the lift thus got, to - allow of getting under her bottom to repair her. - - By great exertion nearly the whole of the compartments forward and - aft of the engine space, and part of the coal bunkers, have been - made tight; and if the tides had ebbed as low as usual, the other - bunkers and the boilers, fireplace and flues, would also have been - made water-tight by these last springs. - - Unfortunately, from the direction of the wind and other causes, - these tides have neither ebbed nor flowed to their full extent; - still, the vessel has been lifted, and some of this lift has been - maintained, and if we were fortunate, it is evidently quite - possible that our utmost expectations might be realized, and - possibly the vessel might be lifted sufficiently to be made tight - without any external assistance. This, however, would be too much - to calculate upon, and the weight to be lifted having been reduced - to one-half what it was, and being capable of still further - reduction, the operation of lifting by camels becomes a much more - practicable undertaking. - - I should now therefore recommend that application be made to some - parties who have had the most experience in such work, to lay their - proposals before the Directors; and that in the meantime we should - continue to make every effort to add to the buoyancy of the - ship.... - - I believe that, in such a case, quiet, sober consideration, - assisted by experience, and by careful examination of all the - circumstances on the spot, will be infinitely more valuable than - the most ingenious and brilliant schemes. And I believe we are most - likely to obtain these conditions by calling in a man like Mr. - Bremner, and leaving him to confer with Captain Claxton, and that - he should have the benefit of our advice and assistance, and then - lay his plans and proposals before the Directors. - -Mr. Bremner and his son, assisted by Captain Claxton, made preparations -for releasing the ship. The system followed was that sketched out by Mr. -Brunel--namely, that of lifting the ship by mechanical arrangements, and -then making good the leaks. The difficulties they had to contend with -are graphically described in the reports which were sent almost daily by -Captain Claxton to Mr. Brunel, and which were afterwards printed by the -Directors at Mr. Brunel's suggestion.[134] - -The principal leak was stopped, and the ship's head raised 8 feet 7 -inches by ramming wedges and stones under her at high water. At last, on -August 27, the ship was floated, and Captain Claxton wrote to Mr. -Brunel:-- - - Huzza! huzza! you know what that means.... I made up my mind to - stop her at the edge of low water, and then examine and secure all - that might discover itself. The tide rose to 15 feet 8 inches. She - rose therefore easily over the rock, but was clear of it by only - just five inches, which shows how near a squeak we had--it was a - most anxious affair, but it is over. I marked 170 yards in the sand - and on our warp, and at that extent I stopped her.... I have no - doubt that to-morrow we shall see her free. - -The following day they started for Liverpool. One hundred and twenty -labourers were hired to work at the pumps, but only thirty-six came on -board, and their services were unavailable, as they spent their time in -discussing how much they were to be paid. Consequently, when the ship -was taken in tow at 4 A.M. on the 28th there was 6 feet of water in the -engine room and 5 feet in the fore hold, and she was making 16 inches an -hour. Men from Her Majesty's ships 'Birkenhead' and 'Victory,' which had -been sent by the Admiralty to assist, were drafted on board, and the -influx of water was reduced to four inches an hour. It was evident that -Liverpool could not be attempted, so they made for Strangford Lough. A -dense fog came on when they were off the entrance, and they pushed on to -Belfast Lough, where the ship was grounded. During the night she was -cleared of water, and the next day she started for Liverpool. The -landsmen who had been hired the previous night to work the pumps were -incapacitated by sea-sickness; and the ship was only kept afloat by the -exertions of Captain Claxton and the dockyard hands who had been sent to -assist in navigating her across. When she arrived at Liverpool she was -placed over a gridiron, on which she sank when her pumps were stopped. - -Notwithstanding the successful result of the efforts made for her -rescue, the stranding of the 'Great Britain' in Dundrum Bay led to the -ruin of the Company; and she was some time afterwards sold to Messrs. -Gibbs, Bright, & Co., of Liverpool, by whom she was repaired, and fitted -with auxiliary engines of 500 nominal horse-power. On a general survey -being made, it was found that she had not suffered any alteration of -form, nor was she at all strained. She was taken out of dock in October -1851, and since that time she has made regular voyages between Liverpool -and Australia. - -She is known as one of the fastest vessels on that line; and remains to -testify to the ability and wisdom of those who, more than thirty years -ago, were daring enough to build so large a ship of iron, and to fit her -with the screw propeller. - - * * * * * - -NOTE (p. 255). - -_Dimensions of the 'Great Britain' Steam-Ship._ - - feet inches - - Total length 322 0 - - The length of keel 289 0 - - Beam 51 0 - - Depth 32 6 - - Feet of water 16 0 - - Tonnage measurement 3,443 tons. - - Displacement 2,984 " - -_Dimensions of original Engines, &c._ - - Number of cylinders 4 - - Diameter of cylinders 88 inches - - Length of stroke 6 feet - - Weight of engines 340 tons - - Weight of boilers 200 " - - Water in boilers 200 " - - Weight of screw-shaft 38 " - - Diameter of screw 15 ft. 6 in. - - Pitch of screw 25 ft. - - Weight of screw 4 tons - - Diameter of main drum 18 feet - - Diameter of screw-shaft drum 6 " - - Weight of coal 1,200 tons - - - - -CHAPTER X. - -_STEAM NAVIGATION._ _INTRODUCTION OF THE SCREW PROPELLER INTO THE ROYAL -NAVY._ - -A.D. 1841--1844. AETATIS 36--39. - - APPOINTMENT OF MR. BRUNEL TO CONDUCT EXPERIMENTS FOR THE ADMIRALTY - WITH VARIOUS FORMS OF THE SCREW PROPELLER, APRIL 1841--TRIALS WITH - THE 'POLYPHEMUS'--OPPOSITION TO MR. BRUNEL'S EXPERIMENTS--TRIALS - WITH THE 'RATTLER,' OCTOBER 1843-OCTOBER 1844. - - -Soon after Mr. Brunel had taken the bold step of recommending the -adoption of the screw propeller in the 'Great Britain,' he was asked to -send a copy of his report to the Admiralty. He did so; and in the course -of a few months was invited to attend the Board on the subject of some -experiments their Lordships proposed to make. - -An interview took place on April 27, 1841; of which Mr. Brunel gives the -following account:-- - - I attended the Board: Lord Minto stated that he wished a complete - experiment to be made on the applicability of the screw to - Government boats, and he proposed to place the conduct of the - experiments in my hands as a professional man. I stated that I - should have great pleasure in doing it, and should take great - interest in it, provided they intended to make a good experiment - and would place it entirely in my hands, without the intervention - of any Government officers, but that I should communicate direct - with the Lords, and of course with Sir E. Parry.[135] He said he - proposed to build a vessel and engines on purpose, and that he - particularly wished it to be left entirely in my hands, and took me - apart to the window to impress this last condition on me. - -Within a fortnight of his appointment, Mr. Brunel invited Messrs. -Maudslay and Field and Messrs. Seaward to send him designs for the -engines: they were to have been of 200-horse power, with a stroke of 4 -feet. The engines were to make a smaller number of revolutions than the -screw, the motion being communicated from the engine shaft to the screw -shaft by drums and straps. This arrangement was adopted in preference to -tooth-gearing, in order to facilitate the variation of the number of -revolutions, in the experiments with different screws. - -The designs ultimately sent to Mr. Brunel for his approval were those of -Messrs. Maudslay and Messrs. Forrester. He reported to the Admiralty in -favour of Messrs. Maudslay's engines. - -Before drawing up the detailed specifications, Mr. Brunel was desirous -of procuring data for estimating the surface of the screw required to -obtain the same resistance as that offered by the paddles of a ship -similar to the new vessel. With this object he applied to the Admiralty -for permission to make an accurate trial of the performances of the -paddle steamer 'Polyphemus' at various speeds. This permission was -granted; the trial, however, was fixed for such an early day that Mr. -Brunel had barely time to make the preliminary arrangements, with the -assistance of his friend Captain Claxton. - -When Captain Claxton arrived at Southampton, the day before the trial, -he found that there was no measured mile set out. He immediately hired -men, got chains, staffs, and flags, and set out both a nautical mile and -a statute mile. They made half a dozen runs each way with the -'Polyphemus,' noting carefully all particulars of speed, revolutions, -&c.; and the results obtained were considered very satisfactory. - -On October 1, Mr. Brunel received information from the Admiralty (now -under the administration of the Earl of Haddington) that Messrs. -Maudslay and Field's tender was accepted. The engines were immediately -put in hand, under Mr. Brunel's supervision. - -When they were approaching completion, he became anxious to learn -something about the progress of the ship which was to have been built -for them. Nowhere could she be found. The minutes were searched at the -Admiralty, and it was ascertained that the ship was ordered, but that no -ship had been laid down. This discovery, as might be supposed, excited -considerable surprise. Mr. Brunel was sent for to the Admiralty to see -Sir George Cockburn, the First Naval Lord. Almost the first words to him -were: 'Do you mean to suppose that we shall cut up Her Majesty's ships -after this fashion, sir?'--Sir George at the same time pointing to a -model of the stern of an old-fashioned three-decker, in which large -slices were taken off to give room for the screw, and the whole of the -lower deck exposed to view, thus making the application of the screw -look very ridiculous. On the model was written, 'Mr. Brunel's mode of -applying the screw to Her Majesty's ships.' Mr. Brunel smiled, and -denied its being his idea at all; he had never seen it before, and knew -nothing about it. 'Why, sir, you sent it to the Admiralty.' This also -Mr. Brunel denied having done. While an enquiry was being made as to -where the model came from, Mr. Brunel employed himself in effacing the -inscription with his knife. When the messenger returned, he reported -that the model had come from the office of the Surveyor of the Navy. He -was sent for, but did not appear. Mr. Brunel, to terminate this awkward -interview, pleaded business, and bowed himself out. - -Mr. Brunel often told this anecdote, and spoke of the adverse influence -which had been exerted in some department of the Admiralty to prevent -the successful issue of these experiments. - -Soon afterwards Mr. Brunel was informed that the 'Acheron' would be -prepared for the screw. He thereupon represented to their Lordships that -the 'Acheron' could not, from her full after-body and other defects, be -converted into such a ship as the Board had originally determined to -construct for trying the screw; and, indeed, her unfitness was admitted -by the authorities themselves. - -To a letter on this subject, in which he stated that the attempt to -apply the screw propeller to the 'Acheron' would not answer any of the -objects which their Lordships had in view, Mr. Brunel received no reply, -and for the next four months was kept quite in the dark as to what was -going on. At length he made enquiries as to the cause of a treatment -which, he said, he had never before experienced from any public body. - -These enquiries proving fruitless, he at last wrote to the Admiralty, -declining further interference, as it had appeared on investigation that -the condition on which he had accepted his position from Lord -Minto--namely, that he should have the entire superintendence of the -experiments--had not been observed. - -On the receipt of his resignation, Mr. Brunel was summoned to the -Admiralty. He thus described his interview in a letter to a friend:-- - - Not a word was said about my complaint of the past, but they said - they wished me to continue the experiments, and that my screw was - to be tried first. I said that was not at all what would suit me; - that I would, if they wished it, conduct an experiment as - originally proposed; that I had no screw, that I was no competitor, - but an arbitrator in whom the Admiralty had perfect confidence; - that I was this or nothing. Then commenced a tedious fencing.... - However, it ended in all parties being written to, and told that - they were to follow my directions, and that I was to proceed to - give such instructions as should enable a full experiment to be - made of all screws generally. I then requested that this time I - might have my instructions in writing. - -In a few days Mr. Brunel received an official intimation that the -'Rattler' was to be adapted for the screw, under his directions. - -The 'Rattler' was a vessel of 888 tons burden, 176 feet 6 inches between -the perpendiculars, and 32 feet 8-1/2 inches beam.[136] She had been -commenced for a paddle-wheel steamer shortly before, and was of nearly -the same tonnage and midship section as the 'Polyphemus,' but she had -not the fine lines aft which were so important for the use of the screw. - -She was not launched until April 13, 1843, just two years after Mr. -Brunel's first interview with Lord Minto; and she was then delivered to -Messrs. Maudslay in the roughest possible state. - -Except during the time that Mr. Brunel was prevented from attending to -business by the half-sovereign accident, he was in constant -communication with the dockyard authorities on matters relating to the -construction of the ship, with Messrs. Maudslay as to the -multiplying-gear and engines, and with Mr. F. P. Smith as to the forms -of the various screws to be tried. - -The engines and screw were fitted in the ship, after considerable delay; -and, on October 24, 1843, Mr. Brunel reported on them in their completed -state. On the 30th, the experiments were commenced. - -More than twenty trials were made between that date and the following -October, when the 'Rattler' went to sea, and Mr. Brunel could not of -course any longer personally superintend the experiments; but, except -on one or two occasions when his place was supplied by an assistant, all -the trials that were made during the first year were conducted in his -presence, and he transmitted the results from time to time to the -Admiralty.[137] - -The performance of the 'Rattler' was found to be satisfactory; and the -position of the engines and screw being below the water line was so -pre-eminent an advantage, that in 1845 the Lords of the Admiralty -ordered more than twenty vessels to be fitted with the screw;[138] and -since that time it has gradually superseded the paddlewheel for ships of -war. - -The services which Mr. Brunel rendered to the country during the whole -of these proceedings were given entirely without pecuniary recompense, -and in the face of opposition and discouragement; but he had the -satisfaction of knowing that he had been mainly instrumental, not only -in introducing the screw propeller into the mercantile navy, but also in -securing its adoption in Her Majesty's fleet. - - - - -CHAPTER XI. - -_STEAM NAVIGATION--THE 'GREAT EASTERN' STEAM-SHIP, FROM THE COMMENCEMENT -OF THE UNDERTAKING TO THE LAUNCH._ - -A.D. 1851--1857. AETATIS 46--52. - - INTRODUCTORY OBSERVATIONS--THE AUSTRALIAN STEAM NAVIGATION - COMPANY--STATEMENT OF MR. BRUNEL'S PROJECT OF A LINE OF LARGE SHIPS - (JUNE 10, 1852)--ADOPTION OF HIS PLANS BY THE EASTERN STEAM - NAVIGATION COMPANY--EXTRACT FROM A LETTER DESCRIBING THE SCHEME - (JULY 1, 1852)--LETTER TO J. SCOTT RUSSELL, ESQ., ON THE FORM AND - DIMENSIONS OF THE GREAT SHIP (JULY 13, 1852)--REPORT ON MODE OF - PROCEEDING (JULY 21, 1852)--REPORT ON ENQUIRIES RELATING TO THE - DRAUGHT AND FORM OF THE VESSEL (OCTOBER 6, 1852)--REPORT ON THE - PROCEEDINGS OF THE COMMITTEE APPOINTED TO CONSIDER MR. BRUNEL'S - PLANS (MARCH 21, 1853)--TENDERS INVITED FOR THE SHIP AND - ENGINES--REPORT ON TENDERS (MAY 18, 1853)--PREPARATION OF THE - CONTRACTS AND SPECIFICATIONS--EXTRACTS FROM MR. BRUNEL'S MEMORANDA - (A.D. 1852, 1853, 1854)--LETTER ON HIS POSITION AND DUTIES AS - ENGINEER OF THE COMPANY (AUGUST 16, 1854)--LETTER ON AN ARTICLE IN - A NEWSPAPER (NOVEMBER 16, 1854)--REPORT ON THE UNDERTAKING - (FEBRUARY 5, 1855)--ARRANGEMENTS PROPOSED FOR OBTAINING - ASTRONOMICAL OBSERVATIONS--LETTER TO G. B. AIRY, ESQ., ASTRONOMER - ROYAL (OCTOBER 5, 1852)--APPOINTMENT OF MR. WILLIAM HARRISON TO THE - COMMAND OF THE SHIP--MEMORANDUM ON THE MANAGEMENT OF THE GREAT SHIP - (OCTOBER, 1855)--LETTER ON THE DUTIES OF THE CHIEF ENGINEER (MARCH - 19, 1857)--SUSPENSION AND RESUMPTION OF THE WORKS. - - -Mr. Brunel's earlier labours in connection with the progress of Ocean -Steam Navigation have been described in the chapters on the 'Great -Western' and 'Great Britain' steam-ships.[139] The 'Great Eastern' is -but the result of the application, under different circumstances, of the -same principles which had guided him in his previous under-takings, the -practical working out of the 'idea which he had frequently entertained, -that, to make long voyages economically and speedily by steam, required -the vessels to be large enough to carry the coal for the entire voyage -at least outwards; and, unless the facility for obtaining coal was very -great at the out port, then for the return voyage also; and that vessels -much larger than had been previously built could be navigated with great -advantage from the mere effect of size.'[140] - -In 1851, four years after the release of the 'Great Britain' from -Dundrum Bay, Mr. Brunel became again connected with the construction of -steam-ships. In that year he was consulted by the Directors of the -Australian Mail Company upon the class of vessels which it would be -advantageous for them to purchase, in order to carry out their contract -for the conveyance of the mails to Australia. He advised them to have -ships of from 5,000 to 6,000 tons burden, in order that they might only -have to touch for coal at the Cape. - -Some of the Directors would not hear of so startling a proposition; but -they nevertheless asked Mr. Brunel to become their Engineer; and he -retained the post till February 1853. Two ships were built under his -direction by Mr. J. Scott Russell--the 'Victoria' and the 'Adelaide.' - -It was, no doubt, his connection with the Australian Mail Company that -led Mr. Brunel to work out into practical shape the idea of 'a great -ship' for the Indian or Australian service, which had so long occupied -his mind; and it appears that in the latter part of 1851 and the -beginning of 1852 he devoted much time and thought to the subject. He -collected facts relating to the trade with India and Australia which -demonstrated the advantages to be gained by a rapid and direct -communication for the conveyance of passengers and troops, as well as of -merchandise. It was with these enlarged views that Mr. Brunel entered -upon the construction of the 'Great Eastern.' He writes in February -1854, 'In February and March 1852 I matured my ideas of the large ship -with nearly all my present details, and in March I made my first sketch -of one with paddles and screw. The size I then proposed was 600 x 70, -and in June and July I determined on the mode of construction now -adopted of cellular bottom; intending then to make the outer skin of -wood for the sake of coppering.' - -In the spring of 1852 he communicated the results at which he had -arrived to Mr. John Scott Russell, Captain Claxton, and other scientific -friends, and also to several Directors of the Eastern Steam Navigation -Company. - -This Company had been formed in January 1851 for the purpose of -establishing an additional line of steam communication by the overland -route, for the conveyance of mails, passengers, &c., between England, -India, and China, with a branch to Australia. However, in March 1852 the -Government determined to grant the contract for the whole service to the -Peninsular and Oriental Company. The Directors of the Eastern Steam -Company were therefore obliged to report to their shareholders that the -object for which the Company had been incorporated could not be carried -out. - -At about this time Mr. Brunel's scheme was brought before the Directors, -and he submitted to them a detailed statement of his project. - -After describing the size and capacities of the vessels then used on the -route between England and the East, and the amount and cost of the coals -they consumed, he continued:-- - - - June 10, 1852. - - The same amount of capital and the same expenditure in money for - fuel now required for a line of ships of the present dimensions - would build and work ships to carry in the year double the number - of passengers, with far superior accommodation, and in about half - the time, and two or three times the amount of cargo; the whole - difference being produced simply by making the vessel _large enough - to carry its own coal_, exactly as when the 'Great Western' was - projected for the New York line, the passage had been considered an - impossible one for steamboats, or, if possible, only at a total - sacrifice of all return for the cost. Certainly, no steamboat then - built could get across except by a chance fair weather passage, and - then only by being completely filled with coals and leaving no room - for passengers or cargo. Simply by building a ship of the size - necessary to take the coal, over and above the accommodation - required for a due number of passengers and a reasonable quantity - of cargo, the passage was rendered perfectly easy and certain, and - has since become a mere matter of course, and an ordinary and - profitable trading voyage. - - The increased size, instead of being a disadvantage, was found, as - predicted by the projectors, to be a great benefit, and gave - increased speed, even beyond that proportionate to the power; and - this steamboat, built in 1836, is still as good as any of her size - afloat. - - Nothing more novel is proposed now, but again to build a vessel _of - the size required to carry her own coals for the voyage_. The use - of iron, which has since 1836 become common, removes all difficulty - in the construction, and the experience of several years has - proved, what was believed before by most unprejudiced persons, that - size in a ship is an element of speed, and of strength, and of - safety, and of great relative economy, instead of a disadvantage; - and that it is limited only by the extent of demand for freight, - and by the circumstances of the ports to be frequented. - -A Committee was appointed to confer with Mr. Brunel and with Mr. Scott -Russell, 'who was fully acquainted with all Mr. Brunel's plans, and had -ably assisted him in maturing them.'[141] - -The Committee reported to the Directors that they had met on the day -after their appointment, when, Mr. Brunel being unavoidably absent, Mr. -Russell had attended and entered into a very full explanation of Mr. -Brunel's plans, and that a long investigation of his proposition had -taken place; that a few days later they had met again, when Mr. Brunel -attended, and that after a further and most satisfactory investigation, -they had come to an unanimous decision in favour of the scheme. This -resolution was adopted, and Mr. Brunel was appointed Engineer to the -Company. - -The following extracts from his reports and correspondence carry on the -narrative till the date of the next meeting of the shareholders -(December 1, 1852), when the details of the project were laid before -them:-- - -_Extract from a Letter describing the Scheme._ - - - July 1, 1852. - - The principle is, as I explained to you, a very simple one--that of - building ships to carry their own coals, instead of incurring large - expenses and great delay in coaling at numerous intermediate - stations; and the result is a large vessel certainly, but one - which, at the same cost of fuel as is now required for small ones, - has, besides that room, for 4,000 or even 5,000 tons (measurement) - of cargo, and as many passengers as offer. Thus the capital - embarked in the one vessel is not so great in proportion to the - tonnage space for cargo as the capital embarked in several smaller - vessels carrying the same amount; while the current expenses are - greatly less, and the speed, and economy of time by that speed and - by avoiding tedious stoppages, greatly in favour of the large one. - Practical men concur with me, not merely in the practicability of - constructing the vessel, but in the great advantage as regards - speed, seaworthiness, and safety resulting merely from the - increased size; while all the mercantile men concur in the opinion - that if goods can be carried direct in thirty to thirty-five days, - the certainty of freight ensures a return far beyond all present - proportion of return to cost.... On these points, of course, I - quote only the opinions of the Directors. On the mechanical part I - offer my own opinion, and may quote those of the first practical - men of the day--Messrs. Maudslay, Messrs. Watt and Co., and J. - Scott Russell, all of whom have assisted me in the project, and are - prepared to join in it. - -_Letter to J. Scott Russell, Esq., on the Form and Dimensions of the -Great Ship._ - - - July 13, 1852. - - The adoption of this plan being now determined upon, we must - proceed to determine the details, and the first step unquestionably - is the determination of the size and form of the ship. Now, in - preparing the general design, I think the following conditions - should be strictly complied with. If any of them appear to involve - any great sacrifice in cost, or to involve any other peculiar - difficulties, these difficulties can be considered afterwards; but - the wisest and safest plan in striking out a new path is to go - straight in the direction which we believe to be right, - disregarding the small impediments which may appear to be in our - way--to design everything in the first instance for the best - possible results strictly according to the principles which theory, - so far as it is supported by practice, teaches us, and without - yielding in the least to any prejudices now existing unsupported by - theory and practice, or any fear of the consequences; we can then - afterwards weigh and balance deliberately the advantages of - adhering to or giving up this or that particular part, or modifying - dimensions, either from motives of economy, or as yielding to - public opinion from motives of policy. - - In determining the lines of the ship, for instance, I should adopt - that which we have reason to believe the best possible without any - concession, or any compromise or regard to any assumed difficulties - of construction, or regard to assumed opinions; these difficulties - will very likely vanish afterwards if disregarded in the first - instance, as in the case of the continuous curve, in which my fresh - ideas had the advantage even of your much greater knowledge, - hampered by a little preconceived idea. With respect to the size, - to arrive at it by constructive calculations from the fixed - conditions that we can lay down is perhaps possible, but rather - difficult, and I think we know sufficiently nearly now what the - minimum size must be to work upon; that, and a trifling alteration - afterwards in the scale, will suffice to bring it to the exact - required capacity. - - The positive conditions, then, are a maximum draught of water of 24 - feet, when leaving the Hooghly with the coals for the voyage home; - and the capacity must be at least 21,000 tons of displacement at - this draught of 24 feet. - - I think you will find that to effect this comfortably you must give - a length of 650 feet at least, and an extreme breadth of 80 feet, - but this beam of 80 feet requiring no fuller entrance than you - would make with a beam of 70 feet, the 80 feet being obtained - entirely by continuing a gentle curvature throughout the whole - length, instead of having any parallel lines. - - If the experiments upon the friction of surfaces turn out as I - hope, and give us reason to expect a very much less resistance from - a copper surface than that now created by painted iron, I suspect - we may be led rather to increase our length and diminish the - proportion of beam; but this is a very serious question, not - entirely dependent on the consideration of the form of least - resistance including friction, but also materially affected by the - consideration of the advantages of the extreme steadiness of motion - which length seems to give. It is a subject which must be well - discussed and well considered, with the assistance of all those - whose opinions and experience are likely to be of use to us. My own - impressions, I confess, derived from considering the cases which we - have, even after the striking result of the 'Ocean Queen,' are that - positive length, independently of relative length, has much to do - with it. When I see that the 'Great Britain,' although with a beam - of about one-sixth of her length at the water line, and a midship - section favourable to rolling, is nevertheless steady, I must - conclude that positive length may compensate very greatly for a - relatively wide beam. Now, we shall unquestionably have abundance - of positive length. We must then be careful not to sacrifice much - to keep a small beam, without being very sure that there are very - great advantages; and, except for the assumed advantages of the - long parallel or equal bearings, the form of least resistance, - including friction, with a draught limited to 24 feet, and a - required displacement of 21,000 tons, would, I apprehend, give us a - beam nearer 90 feet than 70 feet. I should like to know exactly - what the proportion would be without regard to the theory of the - long narrow parallel forms; and then let us consider how much, if - anything, should be sacrificed to attain the advantage assumed to - be attained by relative length. - - Let us therefore have at once the draft of a vessel of 21,000 tons - displacement at the 24 feet water line, and of such form as will in - your opinion give the greatest speed in smooth water, without - seeking to make it narrow. - - We must, of course, also bear in mind the comparative weakness of - form caused by length, and the consequent increased thickness of - material required, besides an actual increase of surface, involving - a very considerably greater quantity and weight of material in the - ship, which last consideration is very greatly in favour of breadth - of beam; for I think you will find that the quantity of iron in - two ships of 600 and 700 feet in length respectively, with the same - displacement and the same ultimate strength to resist strains, will - be fully in the ratio of their length. - - -_Report to the Directors on Mode of Proceeding._ - - - July 21, 1852. - - Since the adoption by the general meeting of the plan recommended - by the Directors, I have been engaged very constantly in maturing - the details of that plan, and considering the course which it would - be necessary to follow in order to carry them out in the surest, - safest, and most efficient manner. - - The steps which are about to be taken are unquestionably in the - right direction, but they are considerable ones, and must be taken - with deliberation and certainty, and without leaving anything - doubtful; and, when determined upon, they must be followed up with - decision. - - Although you will probably determine upon constructing not less - than two vessels in the first instance, yet they must both be - proceeded with at once, and must in fact be exact duplicates of - each other. The success of the two, therefore, depends upon that of - each; there can be no average struck in such a case, but the two - ships must be designed and executed on such principles and with - such perfection that no doubt can exist of the result. - - By well considering all that has been done, by selecting all that - has been most successful, and by a judicious application of such - results to the peculiar circumstances of our case, all this - certainly can, I think, be assured, but it can be assured only by - proceeding with the caution and the decision which the - circumstances demand. - - In the first place, as to the designing of the whole, the principle - being determined upon, much may be ascertained by mere calculation, - but for these calculations data are required, which nothing but - experience can furnish. I have, therefore, availed myself of the - assistance of those most competent to afford the required - information. I have called in to my assistance the gentlemen whom I - had already named to you as best able to give strength to our - position by the value of their opinions, and best able to execute - the various parts of the work with that experience and perfection - which are essential to our success. - - With respect to the form and construction of the vessel itself, - nobody can, in my opinion, bring more scientific and practical - knowledge to bear than Mr. Scott Russell. As to the proportion of - power to be adopted, the form and construction of the engines, - screw, and paddles, besides Mr. Scott Russell, I have had the - benefit of the deliberate consideration and advice of Mr. Field, of - the firm of Maudslay and Field, and of Mr. Blake, of the firm of - Watt and Co. I have written also to my friend Mr. F. P. Smith, to - whom the public are indebted for the success of the screw, for his - advice on the subject. With such assistance I think we may rely - upon the certainty of being able to design and to execute all that - is best in the mechanical and ship-building department. In the - naval department I have had the opportunity also of consulting two - gentlemen, Captain Claxton and Captain Robert Ford, who possess - special knowledge and experience on the subject. I have had several - conferences with all these gentlemen, I have explained fully my - views, and, with their assistance, settled preliminarily some of - the principal points of detail. What I should propose to the - Directors now is, that with that assistance I should proceed to - prepare in detail the design of the ship, and the exact dimensions - and form of the engines; that, in the meantime, I should obtain - information upon certain points which will govern you as to the - mode of contracting for the construction of the ships, and also - that I should be authorised to adopt some means of determining one - or two most important points which must govern some of the - principal dimensions.[142] - - -_Report to the Directors on Enquiries relating to the Draught and Form -of the Vessel._ - - - October 6, 1852. - - Since the date of my last letter to you, recommending that certain - enquiries and investigations should be set on foot to determine - several points which would materially influence the plans I should - have to submit to you, many circumstances have occurred to delay - these investigations. Not having sent any competent person - expressly to Calcutta to ascertain with certainty the draught of - water that might be adopted, I have endeavoured to obtain as much - information as possible upon this point from persons capable of - affording it, who might be in England. - - Several very competent men, captains of long experience in that - particular navigation, and even local pilots of the first standing, - happened to be within reach, and I have had personal communication - with these gentlemen. Notwithstanding, however, these fortunate - opportunities of obtaining information from the best existing - authorities, we are left in pretty nearly the same state of doubt - as to the maximum depth as we should be by a mere inspection of the - charts, the opinion of very competent men varying so much as to fix - this maximum as low as 21 and as high as 23-1/2 and even 24 feet. They - all concur, however, in fixing Diamond Harbour as the point in the - Hooghly which may easily be reached, but beyond which it would be - almost impossible to go. - - A question as to the extent of swell which in so large a ship might - be given to the sides, increasing the capacity without materially - increasing the resistance, involved one of the experiments to which - I referred in my former letter; these experiments have been made, - and the result, such as it was, of the enquiries before referred to - as to the navigation of the Hooghly, led me to direct the - preparation of draughts of three different models of ships, and - upon further consideration of these three, and under the - circumstances, I have come to the conclusion of recommending one - which will have the following dimensions:--namely, 670 feet in - length, 85 feet beam, and a deep water draught of 30 feet. - - Such a vessel would be able to carry her own coal for the voyage - home out of the Hooghly with about 23 feet draught; but if between - now and the period when the exact arrangement must be determined, - it is found expedient not to attempt so great a draught in the - Hooghly, the same vessel will, by coaling at Trincomalee on the - return voyage, be exactly adapted to work out of the Hooghly with a - good cargo of goods and coals for Trincomalee with only 20 to 21 - feet draught. - - I have been in communication with the eminent engine builders whose - names I have mentioned on a former occasion, and with Mr. F. P. - Smith, the inventor of the screw propeller. Some trials and - investigations are still in progress to determine the relative - advantages of a copper and iron bottom, on which question may - depend the arrangements which may be requisite to provide for - docking or rather laying up for cleaning, and when these points are - determined I shall be prepared to lay before you a complete design - of ship and engines for your consideration. - -Efforts were made to induce the public to assist in carrying out the -project. In February 1853, the Chairman (the late Mr. Henry Thomas Hope) -and several of his colleagues formed themselves into a committee for the -purpose of communicating with Mr. Brunel on the subject of his plans, -and reporting to the Board thereon. - -The results of this conference were embodied in the following report -which Mr. Brunel addressed to the Directors:-- - -_Report on the Proceedings of the Committee._ - - - March 21, 1853. - - To enable the Committee to arrive at a correct conclusion on this - difficult question, I had gone through rather lengthy calculations - of the minimum dimensions and the comparative estimated cost of the - ships which would in each case answer the purpose under the several - different circumstances which might be assumed; and the results of - these calculations were laid before the Committee, and the relative - advantages and disadvantages of each assumed case discussed....[143] - - After much discussion, and comparing the probable receipts with the - estimated expenditure, and allowing fully for interest of capital - embarked, I think it appeared to the Committee that as a mere - mercantile transaction, and with reference only to the Australian - trade, the larger vessel would be the most economical, showing not - merely the means of securing the largest return, but involving an - actual diminution of annual expenditure.... - - The Committee were unanimously of opinion that the largest size of - the first class would be the best, and would in every way answer - the objects of the Company. - - The dimensions arrived at by calculation for this ship would be in - round numbers, 670 feet long, 80 feet beam. - - This sized vessel would combine most of the advantages which we - seek to obtain. It would carry coal to Diamond Harbour and back to - Trincomalee; it would afford room for about 800 separate cabins - larger than those now fitted up in packet ships, with large - saloons, capable of accommodating 1,000 or 1,500 first and - second-class passengers; and would carry 3,000 tons weight of - cargo, without making any allowance for that increase of speed - proportionate to the mere increase of size of which we see every - day fresh proofs; the average speed of the ship, with the proposed - power of engine and calculated consumption of coal, would be 14 - knots at the average, making the passage out in 34-1/2 days, say 36; - but with that increased speed which has been shown to take place - with increased dimensions, we may speculate upon the voyage being - performed in 30 days. - - This same vessel, fitted up for the Australian voyage, and loaded - deeper, would carry coals to Australia and back, would take out - 3,000 passengers easily, and a small amount of cargo only, but - could bring back any amount that could be conveniently collected, - or if provision were made for taking in 3,000 or 4,000 tons of coal - in Australia, that additional amount of cargo might be taken in the - passage out. The passage out to Port Philip should be made easily - in 36 days, and home by Cape Horn in the same time. - - The Committee having come to the conclusion that this class of - vessel would best fulfil the several conditions which the - circumstances imposed, I have been engaged in determining the - several details consequent upon this selection of size, and have - put in hand drawings of the ship, which will enable me to arrive - more correctly at the cost, and will enable us to obtain tenders - for the construction. These details involve a great deal of study - and consideration, and the making of the drawings alone requires - some considerable time, so that I do not think much advance can be - made under three weeks from the present date, but I will endeavour - to expedite the work as much as possible. - -Mr. Brunel was authorized to continue his communications with -engine-makers and ship-builders, and to invite tenders. - -After very detailed and careful calculations of the smallest capacity -that would secure the attainment of the objects sought for, the -dimensions of the vessel and the power of the engines were finally -determined; tenders were received from Mr. Scott Russell, Messrs. Watt -and Co., and Messrs. Humphrys and Co. for both sets of engines, and from -Mr. Russell for the construction of the hull of the ship and for placing -her afloat. - -A meeting of the Directors was held on May 18, when Mr. Brunel submitted -the various tenders he had received. The Board agreed to adopt his -recommendations, and to accept the tenders of Mr. Scott Russell for the -ship and paddle engines, and that of Messrs. James Watt and Co. for the -screw engines. - -The following report, which Mr. Brunel placed before the Directors, -gives a detailed account of the steps he had taken to procure the -tenders, and the grounds on which he had formed his judgment of them:-- - -_Report on Tenders._[144] - - - May 18, 1853. - - According to your instructions, I applied to the several parties - with whom I had previously been in communication on the subject of - the engines and ship, for tenders for their supply. As regards the - engines, I drew up a short specification, defining generally what - was required, and leaving the parties to make their own designs and - propose to me the form of engine they would adopt. - - With respect to the ship, where no such variation could be - permitted, I have had very detailed drawings and specifications - prepared. - - Copies of the specifications are annexed. - - In defining the power of the engines and boilers, I have, in - conformity with my own views and of those of several of the - Directors, who have expressed themselves strongly on the subject, - required a very full amount of power, without naming the nominal - horse-power, which is a very vague mode of defining anything but - the cost which by custom is made dependent upon that nominal power; - but I have defined dimensions of parts and surface of boilers which - will ensure the means of exerting a very large amount of power. - - As regards the ship, I have not spared strength of materials, and - have required the best workmanship. - - The result of this application for designs and tenders is, upon the - whole, very satisfactory, although two of the parties from whom I - had hoped to have received proposals have not been able to send - any.... - - Mr. Blake, of the firm of Watt and Co., and Mr. J. S. Russell and - Mr. Humphrys, have, as I had before reported, devoted much - attention to the subject: from these gentlemen I have received - distinct well-considered designs of the screw and paddle-engines. - - I have been in frequent communication with these gentlemen, and - have seen their plans while in progress, and have made my - suggestions upon them, and assisted more or less in maturing them, - and at all events in preventing the adoption of any principle or - arrangement that I should afterwards object to. Notwithstanding - this, the three designs, particularly for the screw engines, are - totally dissimilar, and I am placed in the difficulty of having to - choose between three totally different plans, each designed by - skilful and experienced men, and each possessing many known and - acknowledged advantages. - - I should also observe that, although I have known the general - arrangement which each would adopt, I did not receive the plans or - the tenders which I now forward until last evening, and that of Mr. - Humphrys as late as 10 o'clock this morning, and that I have not - therefore had time to draw up any very detailed report upon them. - - The following are, however, the principal considerations which - influence me in the selection which I am disposed to recommend. - - It must be borne in mind that the screw engines will be the largest - engines that have yet been made. The principal part of the - propelling power of the ship will be thrown upon the screw; and - upon these engines therefore will mainly depend the performance of - the ship, and particularly upon their constant never-failing - working, probably for thirty or forty days and nights, must depend - the certainty of the ship's performance.[145] Under all these - circumstances, the compactness and stiffness of framing, the - greatest possible simplicity of construction, and the fewest - possible number of parts, and, finally, the absence of any novelty, - however promising, that can introduce any unforeseen difficulties, - are conditions which would outweigh in my mind many advantages that - might, and I think would, be attained by several arrangements which - have been suggested. - - All the designs now submitted comply with these conditions to a - very considerable extent ... but the extreme simplicity of Mr. - Blake's engine leads me to prefer it. - - As regards the paddle engine, I unhesitatingly give the preference - to that proposed by Mr. Russell. I believe it to be as simple an - arrangement as can be adopted for engines with such a slow motion - and so long a stroke as these must have, and the single crank in - the centre I consider a great advantage.... - - As regards a contract for the ship, I have found it more difficult - to proceed in the ordinary course. The conditions which we must - ensure of quality of workmanship and execution, under close - inspection and within reach of one's own supervision, are not - easily attained; and, though as a matter of course readily promised - and undertaken by all ship-builders, they are rarely secured. It is - essential also that the ship should be built where the engines can - be readily fixed on board before launching, and in a yard which can - be devoted to the purposes of the ship, and whence the launching - can be effected with the engines and boilers on board. - - All these are conditions not easily secured. I have been in - communication with one or two parties, and the result is a tender - from Mr. J. Scott Russell, which I enclose, and which has in fact - been framed upon my calculations. Owing to the recent rise in iron - it is somewhat, but not materially, above the amount at which I had - originally estimated the vessels; but the tender, founded upon the - supposition of two such vessels being ultimately ordered, is as - nearly as may be the same as my original estimate, and upon the - whole I consider the tenders both for engines and ships very - satisfactory and confirming fully our previous calculations. - - These tenders do not include, in the case of the engines, either - the screw itself or the paddle wheels, nor, in the case of the - vessel, the cabin fittings, masts, and rigging, boats, or stores. I - should estimate these roughly at 50,000_l._ more,--at least such an - allowance ought to be ample; but these details will require a great - deal of consideration, and could not be included in the original - contracts; while at the same time they can mostly be better and - more economically supplied by competition or by arrangement with - the special makers of the respective articles.... - -During the next six months Mr. Brunel was engaged in preparing the -formal contracts and specifications. These documents were settled with -much care, and after frequent communications with the contractors, who -consented to the insertion of clauses which gave the full control and -supervision over every part of the work to the Engineer, with very large -powers of interpretation. They required, however, that, should Mr. -Brunel cease to act as Engineer, any disputed point should be settled by -arbitration, and not by his successor. - -Besides the delay occasioned by the magnitude and novelty of the -undertaking, there were other difficulties which helped to postpone the -commencement of the works. The Directors were unable, under their -charter, to enter into any contracts until a certain amount of their -capital was actually paid up; and, as several shareholders had retired -when the change of plans was determined upon, it was no easy work to get -the shares taken. That this was eventually accomplished was due mainly -to the exertions of Mr. Brunel and Mr. Charles Geach, one of the -Directors.[146] 'Could I have foreseen,' Mr. Brunel writes, 'the work I -have had to go through, I would never have entered upon it; but I never -flinch when I have once begun, and do it we will.' - -Several times they nearly broke down, but at length the contracts were -signed, and on the same day, December 22, Mr. Brunel gave the formal -notice to the contractors to proceed with the works. 'After two years' -exertions (he wrote), 'we are set going, the contracts entered into, and -the work commenced.' - - _Extracts from Mr. Brunel's Memoranda_, A.D. 1852-1853. - - _July 11, 1852._--The dimensions I commenced with in March last, of - 650 x 70 x 30 appear after all to be not far wrong, according to - present views. I make them now 700 x 70 x 24 about; but much - depends upon the last dimension, the draught. If another foot or - two can be safely taken it will be of great advantage.... With this - size of vessel, having a midship section of about 1,800, and a - length of 700, I assume a nominal horse-power of about 2,500. The - first question of importance is, in what proportion shall this be - divided between the screw and paddles?... My present impression is - to halve the power between the two. - - In both the engines every known means must be adopted to secure - efficiency:--1, An excess of boiler power; 2, expansion - permanently, say at 1/3; 3, steam of not less pressure than 20 - lbs., and I should prefer 25 lbs.; 4, that cylinders, particularly - top and bottom, slide chest, and steam pipes, be all jacketed, and - the jacket supplied with steam from an auxiliary boiler of at least - 10 lbs. more pressure than that of main boilers; and it would be - very desirable to make some experiments to determine whether it is - not worth having a heating apparatus to heat the steam immediately - before it enters the cylinders.[147] - - _July 17._--After a long conference with Mr. Field, I continue of - the opinion that it would be well to apply about three-fifths of - the power to the screw and two-fifths to the paddles, and probably, - as the vessel gets light, diminishing a little the expenditure of - power on the paddles, and keeping up the full power on the screw. - Mr. Field is not in favour of increasing the pressure of steam - beyond 12 lbs. or 15 lbs., on the ground that all the mechanical - difficulties increase rapidly without a corresponding advantage, - particularly where size and weight are not so important. There - seems much truth in this.... The possible advantages of a slight - increase are not sufficient to justify the risk of the possible new - difficulties in a work on so large a scale. Nothing uncertain must - be risked. These arguments do not apply to the jacketing and - heating, which Mr. Field also deprecated, or rather discouraged, - simply on the ground of the trouble and difficulty of effecting it, - but he admitted that all experience went to show the advantages of - it; and as to the difficulties, which I could not see, they involve - no other risk than that of being useless: they cannot do mischief. - The heating of the top and bottom of the cylinders, I think, must - be particularly important in a short-stroked engine working - expansively. In a cylinder of 80 inches diameter and 40 inches - stroke, having regard to the _time_ of contact, the area of the - bottom will be nearly equal in effect to the surface of the - cylinder. - - _July 19._--After much consideration, I think I feel satisfied that - the best construction will be to have strong bulkheads every 30 - feet or thereabouts, this distance being dependent on what is - required for one set of boilers and its stock of coals; these - bulkheads being carried right up wherever practicable--I think - every alternate one may be--and then place the main ribs of the - ship, and even at least two main deck beams, _longitudinal_ instead - of _transverse_. - - _February 2, 1853._--Several drafts of ships have been made and - much consideration given to the subject, and frequent discussions - with various parties. The result of all is that my present views - are as follows:-- - - The ship, all iron, double bottom, and sides up to water line, with - ribs longitudinal like the Britannia tube. I have not been able to - devise any good mode of determining the relative amount of friction - of a copper and an iron surface; and, although I believe in copper, - it would not do to act on mere belief. I therefore at present - settle iron, the surface being carefully made smooth. Doubts have - come across me also as to whether with a very long surface the - difference between the smoothness will so much affect the total - resistance. Is not a film of water, after a certain distance, - carried with the body? and, if so, its greater or less roughness, - if not producing currents, is almost unimportant. Would there be - any difference in the resistance of a fine file or a rough one - drawn through tallow, if they both covered themselves with grease? - Is there any similarity? As to size, if we are to go round the - world,[148] I do not think we can do with less than--length, 730; - beam, 85; draught deep, 34; and I assume a nominal horse-power of - engines equal to 1-1/4 of the sectional area at 30 feet; but, taking - consumption as a better measure, and assuming that every possible - economy is practised, and every refinement introduced that can - produce economy, I shall assume 7-1/2 lbs. per hour per nominal - horse-power, or say 0.08 ton per day per horse-power; and as I - assume the horse-power to be 1-1/4 sectional area, it makes the - consumption =0.1 ton per day per foot of sectional area. And this - is a very large allowance and ought to ensure a very high speed. In - order to effect the utmost economy, I should work up to 20 lbs. - steam (calling it 16 lbs.), cutting off certainly at 1/3 the - stroke, and adopting every precaution to keep the steam hot and the - condenser cool. The latter depends, I believe, solely upon the - perfect dispersion of the injection water, so that the condensation - of the steam may take place suddenly, otherwise the same amount of - water may condense the steam _in time_, the same amount of heat be - given off, the same quantity of injection water used, and yet the - condenser be always full of steam at a good pressure. It might be - well worth the experiment to try the effect of a large injection at - the moment of the exhaust port being opened; but above all things I - believe the heating of the steam to be important; and for this - purpose I should jacket the steam pipes and cylinders top and - bottom, and heat with high pressure steam, say at 60 lbs.--I have - increased this pressure the more I think of it; 60 lbs. would be - above 300 degrees, and 20 lbs. not quite 260 degrees; therefore - there would be a full 40 degrees of surplus to ensure the - temperature. I have a great tendency to believe in the advantage of - further heating even, which might be done by a Perkins' arrangement - of hot water; but possibly the new conditions, as regards oiling, - &c., might involve difficulties not desirable to introduce in this - case. In the boilers it will also be necessary to adopt every - refinement which has been found really to answer, although not - always adopted; above all, every means of keeping them clean--scum - pans, and Field's exchanging apparatus. But what would be even more - effectual would be some easy means of removing a whole bundle of - tubes and replacing them by clean ones; and surely this would not - be difficult, the tubes being large and with plenty of space, so - that a man could pass his arm between. A rather important addition - to boilers would also be a means of blowing off without noise. - Several modes would seem to be possible, but whatever plan is - adopted, it should be one which is completely self-acting, and - perfectly effectual when used suddenly and without any preparation, - and at a moment of confusion and alarm. Blowing through a wire - gauze pipe would probably be as likely a way as any.[149] - - The more consideration I give to the subject the more disposed I am - to adopt oscillating engines for both screw and paddles. The - extreme simplicity and small number of parts, and compactness, and - the direct action of every resistance to the force which it is - wanted to resist, seem to leave nothing to be desired, and would - seem to make it a better and more mechanical arrangement of a - cylinder and crank than any other, quite independently of the - object for which it was originally designed, which was simply - 'stumpiness.' - - _February 21._--The original line (to Calcutta) seems likely, after - all, as usual with most original ideas, to be the best; at all - events, so good that the vessel must be built to be able to go - there. The dimensions best fitted for this would seem to - be--length, 700 feet; beam, 85 feet; depth of hold, 58 feet; screw, - 24 feet; paddle 60 feet. If arranged for Calcutta, we must arrive - there on an even keel, and therefore, to maintain the most equal - level for the paddles, they must be kept well forward, and the - change principally at the stern. Engines indicated horse-power - 8,000; steam at 25 lbs.; auxiliary steam at 60 lbs. - - The ship to be lighted with gas, to be thoroughly ventilated by - mechanical means, having large air trunks, with small pipes and - valves to each cabin, with the means of warming this air in cold - latitudes and seasons, and cooling it in the more frequent cases of - hot climates. The ship must be steered from the forecastle, whence - a perfect look-out must be kept with fixed telescope, &c., and - speaking pipes and bells to the engine rooms. - - _March_ 14.--At a meeting of the Committee, held this evening here, - the several costs and qualities of four different sizes of ships, - of which all the calculations had been made by me, namely:-- - - No. Length Breadth Mid. Sec. Draught - 1 663 79.9 1,646 24 - 2 634 76.39 1,640 25 - 3 609 73.5 1,639 26 - 4 730 87 2,090 28 - - were discussed, and the No. 1 determined upon as the best under all - the circumstances. I should propose, therefore, to make the - dimensions of No. 1:--length, 680 feet; beam, 81 feet, to be - swelled to 83 feet; extreme draught, 30 feet; mean, 24 feet; daily - consumption, say 200 tons. - - This ship can carry her coal to Calcutta, and arrive and leave with - only 21 feet 6 inches draught, having 9 days' coal and 3,000 tons - cargo; or she could first go to Australia and back, without or with - very little cargo out, and consequently would take out as much - cargo as you might choose to send coal for her to Australia.... - - These dimensions are worked out in the design No. 5 (April 9, - 1853), but they would be better for a slight increase, if the 83 - feet were made 85 feet, and the 680 feet were made 700. We should - have an increase in capacity of 83 x 680=56,440 to 85 x 700=59,500, - or 6 per cent. of displacement. This would bring the displacement - at 32 feet draught up to 31,250 tons. - - _March_ 22.--Settled the various dimensions of scantlings with S. - Russell to enable him to direct drawings of all details to be got - out. - - _April_ 28.--We are now seeking tenders for engines and ship of - the following dimensions:--Length, 680 feet; beam, 83 feet; mean - draught, about 25 feet; screw engine, indicated horse-power 4,000; - nominal horse-power, 1,600; paddle, indicated horse-power, 2,600; - nominal horse-power, 1,000; to work with steam 15 lbs. to 25 lbs.; - speed of screw, 45 to 55 revolutions; paddle, 10 to 12. - - Among the details of improvements still to be considered are the - receiving through measures the coal from the bunkers, and running - it on tramways and waggons to the front of the fires, thus at the - same time measuring out accurately the hourly consumption, and - saving labour; but a still more important object, the use of clean - water--that is, using the same water over again--is well worth - considering; and it is well worth the experiment, whether cooling - down the water of condensation to use again is not in fact the - easiest way. With an unlimited supply of cooling water this ought - to be easy. - - _August 7._--Memoranda for engines.--Very sensitive governors to be - applied to both engines to prevent running away. - - _November 18._--It is curious that the above should be the last - memorandum, as I now open the book to make the same in consequence - of the accident to the 'Agamemnon.'[150] - - There can be no reason why a sensitive governor should not act in - less than one revolution of the crank, and act upon a tumbler which - should shut off instantly the expansion valve. There should be two - such governors, one to each end of the crank shaft, and they should - work direct from a spur wheel from the shaft without any - intermediate shafting, to give elasticity, or to risk breaking. - (Query, hydraulic governors?) - - The auxiliary engine and boiler to be at least 20 feet from bottom, - and, better still, above load water line, or so boxed as to be out - of reach of water; so that if the ship grounded and filled, this - engine would remain serviceable for pumping or anything else. - -The history of the 'Great Eastern' has now been traced up to the date of -the contracts for the construction of the ship and her engines. - -The following selections from Mr. Brunel's memoranda illustrate the -progress of the design during the early months of the year 1854:-- - - _February 25, 1854._--The details of construction, both of engines - and ship, involve an immense amount of thought and labour. I have - devoted a great deal of time to it already, and yet even the - preliminary details either of engines or ship are far from being - satisfactorily settled. I have no record of the many consultations - hitherto held on the subject, but shall hope to keep one hereafter. - On the 6th inst., some of the drawings of the ship and of parts of - the engines, having been several times revised and altered, being - ready, I spent the greater part of the day at Millwall[151] in - going again into them, and settled some parts, such as the - dimensions, &c., of cranks, and bearings, general form of engine - frame, and some of the general principles of framing and plating of - the ship. Some other consultations have been held, and again to-day - (February 26) I have spent some hours at Millwall.... Discussed the - details of a midship section, the drawings of which were in a - forward state; directed that the cabins should positively be made 6 - feet 6 inches each in the clear, and the bulkheads made subordinate - to this; found that it could be done without difficulty, and - without causing any mechanical objections in construction. I am - anxious to have some approximate estimates of weights. - - It is evident that large weights may most easily be wasted or saved - by a careless or close consideration of the best application of - iron in every single detail. I found, for instance, an unnecessary - introduction of a filling piece or strip, such as is frequently - used in ship-building to avoid bending to angle irons; made a - slight alteration in the disposition of the plates that rendered - this unnecessary; found that we thus saved 40 tons weight of iron, - or say 1,200_l._ of money in first cost, and 40 tons of cargo - freight--at least 3,000_l._ a year. The principle of construction - of the ship is in fact entirely new, if merely from the rule which - I have laid down, and shall rigidly preserve, that no materials - shall be employed on any part except at the place, and in the - direction, and in the proportion, in which it is required, and can - be usefully employed for the strength of the ship, and none merely - for the purpose of facilitating the framing and first construction. - - In the present construction of iron ships the plates are not - proportioned to the strength required at different parts, and - nearly 20 per cent, of the total weight is expended in angle irons - or frames, which may be useful or convenient in the mere putting - together of the whole as a great box, but is almost useless, or - very much misapplied, in affecting the strength of the structure as - a ship. - - All this misconstruction I forbid, and the consequence is that - every part has to be considered and designed as if an iron ship had - never before been built; indeed I believe we should get on much - quicker if we had no previous habits and prejudices on the subject. - - _March 3._--Mr. Blake [_of the firm of Messrs. James Watt and - Co._], called, and went fully into the general drawings which he - brought. On the necessity of large surfaces he quite concurred with - me. The extent to which such a general principle should be carried - is of course very difficult to determine; my idea is that it has - never yet been approached.... - - _March 10._--Engaged all the afternoon at Millwall.... Settled and - signed the drawings of crank and piston rods. Went into many - details of ship.... - -The extracts from Mr. Brunel's correspondence which follow, have been -selected as containing a definition in his own words of the position he -held as Engineer to the Company by which the great ship was built. - - _Letter to the Secretary of the Eastern Steam Navigation Company._ - - [This letter was written in consequence of a resolution of the - Directors, asking Mr. Brunel to recommend them a resident engineer, - in order that constant supervision might be exercised over the - works, and frequent reports made to the Board. - - The Directors rescinded their resolution; but this letter is - inserted as showing, in clear and forcible language, Mr. Brunel's - view of the nature of his duties and responsibilities, and as - laying down what in his opinion ought to be the relations between - the Directors of a Company and their Engineer.] - - - August 16, 1854. - - ...It surely cannot be necessary to remind the Directors that the - very unusual stake which as a professional man I have been willing, - perhaps imprudently, to risk on the success of this project--I mean - stake of professional character, not mere pecuniary risk--must - secure a much greater amount of attention to any step, and - supervision of any detail on my part, than any ordinary - professional engagement would obtain; the heavy responsibility of - having induced more than half of the present Directors of the - Company to join, and the equally heavy responsibility towards the - holders of nearly half of the capital, must ensure on my part an - amount of anxious and constant attention to the whole business of - the Company which is rarely given by a professional man to any one - subject, and, as it seems to me, ought to command a proportionate - degree of confidence, or rather command entire confidence, in me, - if any at all, for in such a case there can hardly be any medium. - The fact is, that I never embarked in any one thing to which I have - so entirely devoted myself, and to which I have devoted so much - time, thought, and labour, on the success of which I have staked so - much reputation, and to which I have so largely committed myself - and those who were disposed to place faith in me; nor was I ever - engaged in a work which from its nature required for its conduct - and success that it should be entrusted so entirely to my - individual management and control.... - - The Directors have a right to expect, and will ever receive, from - me the fullest information and the most unreserved communication - upon all points as they arise, as from one who feels the - responsibility of being their sole professional adviser in a very - important and serious business, in which we are all embarked, and - all deeply interested; but I cannot act under any supervision, or - form part of any system which recognises any other adviser than - myself, or any other source of information than mine, on any - question connected with the construction or mode of carrying out - practically this great project, on which I have staked my - character; nor could I continue to act if it could be assumed for a - moment that the work required to be looked after by a Director, or - by anybody but myself or those employed directly by me and for me - personally for that purpose. - - If any doubt ever arises on these points I must cease to be - responsible, and cease to act. - -_Letter to the Secretary of the Eastern Steam Navigation Company._ - - [In explanation of the following letter it need only be stated that - an elaborate article on the great ship appeared in one of the - London newspapers of November 1854. Mr. Brunel's name was only once - mentioned throughout the whole of it, and in these words: 'Mr. - Brunel, the Engineer of the Eastern Steam Navigation Company, - approved of the project, and Mr. Scott Russell undertook to carry - out the design.'] - - - November 16, 1854. - - Since I wrote to you I have taken the trouble to read through the - long article in the----, and am much annoyed by it. I have always - made it a rule, which I have found by some years' experience a safe - and profitable one, to have nothing to do with newspaper articles; - but then, if on the one hand the works I have been connected with - have rarely been puffed (never by me), they have also been rarely - affected by misstatements; as such notices, when not inserted by - interested parties, are always slight and unauthentic, and drop - without producing any effect. This article in the----, however, - bears rather evidently a stamp of authority, or at least it - professes to give an amount of detail which could only be obtained - from ourselves; and if, as I think is the case, copies of it have - been circulated by us, it may acquire the character of being an - authorized statement; and, as such, I am individually much annoyed - by a great deal that is in it, and by the omission of much that - might with propriety have been introduced. - - What is constantly repeated or implied, and remains uncontradicted, - is at last received almost unconsciously as fact even by those who - have the means of knowing it to be incorrect, if they thought about - it; and, although from system I have never interfered with - newspaper statements, it has not been from any affected or real - indifference to public opinion, perhaps it was more from pride than - modesty, and therefore I am by no means indifferent to a statement - which would lead the public, and perhaps by degrees our own - friends, to forget the origin of our present scheme, and to believe - that I, happening at the time to be the consulting Engineer of this - Company, which I was not, and having had no peculiar connection - with previous successful improvements in steam navigation, allowed - them to adopt some plan suggested by others, who I suspect, if even - such were the case, would never appear to share with me the - responsibility if any failure should result. Of this certainly I - have no fear, but at the same time I am desirous of something more - than mere immunity from blame. - - I not only read this article once, but I was so struck by the - marked care shown in depreciating those efforts which I had - successfully made in advancing steam navigation, and mainly on the - strength of which no doubt I originally obtained the confidence of - the Directors, which induced them to enter upon our present bold - undertaking, that I read the paper a second time, and for the very - reason that I have for so many years shunned public writings, - namely, to escape misstatements, I feel compelled on the present - occasion to take some steps publicly to correct those erroneous - impressions, which must be created by a document having the - appearance of emanating from ourselves.... - - The objectionable points that I refer to evidently did not strike - you, and that is a strong proof how easily incorrect impressions - insinuate themselves unawares; but I feel strongly that a judicious - friend would not have failed to do justice to the spirited - merchants of Bristol, who, in spite of the strongest condemnation - of the plan by the highest authorities, and the ridicule of others, - persevered in building and starting the first transatlantic - steamer. The circumstances as regards the 'Sirius' are coloured so - as to be quite incorrect; and the same friendly hand would not have - thrown ridicule, and that by a positive false statement, upon that - which he at the same time admits to have been the means of almost - introducing two of the greatest improvements in steam navigation. A - writer wishing success to our enterprise would not have omitted to - mention that I had a claim to public confidence on this occasion, - for the reason that I was at least the principal adviser in those - previously successful attempts. - - And lastly, I cannot allow it to be stated, apparently on - authority, while I have the whole heavy responsibility of its - success resting on my shoulders, that I am a mere passive approver - of the project of another, which in fact originated solely with me, - and has been worked out by me at great cost of labour and thought - devoted to it now for not less than three years.... - -The works had been commenced in the spring of the year 1854, and the -progress of the ship towards completion was eagerly watched, both by -scientific men and by the general public. - -The newspapers and periodicals of the day frequently contained -descriptions of the work, and statements of the anticipated performances -of the ship, often very much exaggerated. The writers seem to have been -quite at a loss how to convey to their readers any idea of her size, and -they generally attempted to do so by comparing her dimensions with those -of some of the well-known streets and squares in London.[152] - -In the beginning of the year 1855, the longitudinal and transverse -bulkheads, which formed the main framework of the ship, were completed -for nearly 400 feet of the centre portion, and the plating was being -fixed in place. - -As the general design was now settled, it was thought that the time had -arrived when it would be desirable for Mr. Brunel to describe at some -length the nature of the undertaking, and the manner in which it was -being carried out. - -_Report to the Directors of the Eastern Steam Navigation Company._ - - [This Report was published at the time and excited much - attention.[153] The paragraphs which describe the arrangements - proposed for launching the ship have been omitted, as they will - more conveniently be inserted in the following chapter.] - - February 5, 1855. - - * * * * * - - Although the simple description of the present state of the works - of the ship and engines, and of what has been done during the last - six months, may be summed up in a few words, I shall, in compliance - with the request of the Directors, embody in this the substance of - the several other reports which I have from time to time made to - the Court of Directors during this half year, and take this - opportunity of laying before the proprietors the fullest - information upon our plans and proceedings. In doing this it may be - difficult to avoid some appearance of repetition of statements - previously made; but I have thought it better, even at the risk of - this, to refer to the objects we have had in view, and explain - fully the nature of the works we have undertaken, and the manner in - which we are carrying them out. - - The construction of the vessel is the portion of our work which, - without being actually novel, involved in all its details the - greatest amount of special consideration and contrivance. - - The unusual dimensions, the general form and the mode of - construction of all the parts involved by these dimensions, the - necessity of studying each part in detail, so as to obtain, by - judicious mode of construction alone, the greatest amount of - strength with the minimum amount of material; all these - circumstances, and particularly the last, have rendered necessary a - very large, though unseen, amount of labour in the preliminary - plans and stages of the work; and, although I had for nearly two - years before the contracts were entered into, devoted a great deal - of time and thought to the subject, yet of course until the exact - size of the vessel, and the general plans of the Company, had been - finally determined upon none of these matters could be entered into - in detail. Much time has consequently been required to mature and - prepare these plans; and as I have made it a rule from the first - that no part of the work should be commenced until it had been - specially considered and determined upon, and working drawings in - full detail prepared, and, after due deliberation, formally settled - and signed, the work did not make at the onset that display of - progress which might have been made, if less regard had been paid - to establishing a good system which would prevent delays hereafter, - and ensure a more perfect and satisfactory result. I am not - prepared to say that the work is in that state of progress which - will ensure its completion within the period fixed in the contract; - but I am quite certain that if we had proceeded with less system we - should have considerably delayed the final completion. - - I shall now refer to a few of the principal peculiarities in the - construction of the ship. - - In the preparation of the detailed plans, I have carried out fully - those principles which I originally described as leading features - of the construction. - - The whole of the vessel is divided transversely into ten separate - perfectly water-tight compartments by bulkheads carried up to the - upper-deck, and consequently far above the deepest water lines, - even if the ship were water-logged, so far as such a ship could be; - and these are not nominal divisions, but complete substantial - bulkheads, water-tight, and of strength sufficient to bear the - pressure of the water, should a compartment be even filled with - water; so that if the ship were supposed to be cut in two, the - separate portions would float; and no damage, however great, to the - ship's bottom, in one or even two of these compartments would - endanger the floating of the whole, or even damage the cargo in the - rest of the ship, or above the main-decks of the compartment in - question, and all damageable cargo would be stowed above that deck. - Besides these principal bulkheads there is in each compartment a - second intermediate bulkhead, forming a coal bunker, and carried up - to the main-deck, which can, on an emergency, also be closed. - There are no openings under the deep-water line through the - principal bulkheads, except one continuous gallery or pipe near the - water line, through which the steam pipes pass, and which will be - so constructed as to remain closed, the opening being the - exception, and the closing again being easy, and the height being - such that, under the most improbable circumstances of damage to the - ship, ample time would be afforded to close it leisurely, and to - make it perfectly water-tight. I have also adopted the system, to - be followed rigidly and without exception, of making no openings - whatever--even by pipes and cocks--through the ship's bottom, or - through the inner skin below the load water line, and I attach much - importance to this system. - - In the majority of cases in which steamboats are compelled to put - into port from failure of bilge-pumps and other really trifling - defects, no such serious consequence would have resulted, but from - the difficulty and almost impossibility of remedying at sea any - defects in the numerous pipes and openings now carried through the - ship's bottom, wherever convenient, and without much regard to the - danger of doing so. - - I have found no great difficulty in carrying out this system - completely, and the advantages, both as regards safety and the - facility of remedying defects without delaying the ship on her - voyage, must be obvious. - - Independently of the security attained by the perfect division of - the ship into really water-tight compartments of a sufficient - number, so that the entire filling of one or even two of them will - not endanger the buoyancy of the whole, the chances of any such - damage as can cause the filling of one of them are greatly - diminished by the mode adopted in the construction of the ship's - bottom. The whole of the vessel (except the extreme stem and stern, - the whole buoyancy of which is comparatively unimportant from the - fineness of the lines), up to a height considerably above the - deepest water line, is formed with a double skin, with an - intervening space of about three feet. This arrangement resulted - originally from the system of construction I adopted, in which the - bulkheads, placed at intervals of twenty feet, form the main - transverse frames or ribs of the ship, and in the intermediate - space the material is disposed longitudinally in webs connecting - the two skins, giving to the whole much greater strength with the - same amount of material; but one of the most important results has - been the great increased security attained, as the outer skin may - be torn or rent against a rock without causing the ship to leak. - - The space between these two skins is thus divided, by the - longitudinal beams or webs and the principal bulkheads, into some - fifty separate water-tight compartments, any one or more of which - may be allowed to fill without materially affecting the immersion - of the ship. - - Besides the main transverse bulkheads, at about 60 feet intervals, - there are two longitudinal bulkheads of iron running fore and aft, - at about 40 feet in width, adding greatly to the strength of the - whole, and forming, with the transverse bulkheads, being all - carried up to the upper deck, fire-proof party walls, cutting up - the whole into so many separate parts, that any danger from fire - may be almost entirely prevented. - - The transverse bulkheads being perfect, there being only one - door--and that of iron--in each, at one of the upper decks, all - currents of air or means of communicating fire may be completely - cut off; and with an additional precaution, which I will refer to - afterwards, besides the most ample means of supplying water, I - believe that all possibility of danger from fire may be completely - prevented. - - All these principles of construction being kept in view, the - details of construction--that is, the arrangement and due - apportionment of the strength and sizes of all the plates, and the - mode of fastening them--having been determined separately, the - plates have been made at once of the required dimensions, and the - work has proceeded systematically. This system is the most - important, as securing not only good work, but affecting, to a much - greater extent than might at first be supposed, the total weight of - the ship; which, although the terms of the contract protect the - Company against any excess of expenditure beyond a certain fixed - sum, is yet of the greatest importance, as will be easily - understood when I mention the fact that several merely trifling - alterations in the modes of arranging the plates and other details - have caused an economy of 20 to 50 tons each, and that the vessel - may thus be made capable of carrying 200 to 300 tons more of coal, - cargo, or provisions; or iron to the same amount may be usefully - applied to strengthen other parts or effect useful additions. - - The details of the engines have all been settled; and the principal - parts, as already stated, are in an advanced state of completion. - - In considering the plans of those engines, the largest that have - yet been manufactured, I have endeavoured to ascertain what may be - termed the weak points of the best engines hitherto constructed by - the same or by other makers--those points in which experience has - pointed out deficiencies--and to provide fully against similar - defects in our case. - - Before commencing the boilers, I have taken every means in my power - of profiting by the experience of others, and have collected all - the evidence and opinions as to the precise form and proportions - which have been found most efficient; and particularly such as have - been found best suited to the combustion of anthracite coal. A very - great difference is found to exist in the useful and economical - results of boilers, even of good manufacture. Some are noted for - the power of producing rapidly abundance of steam, at the cost of - great consumption of fuel; others have the opposite qualities, and - some combine successfully both those qualities which are desirable. - It might have been supposed that all points of such a simple - subject would have been long since settled, and that no boiler - would be made inferior to the best. Such is not, however, the case; - and although the differences of construction are in themselves - slight, the difference of result is often considerable. - - I have taken some pains to satisfy myself on these points, and have - endeavoured to select and to copy the most successful boilers; and - in order to remove all doubts as to their fitness for the use of - anthracite, I have made an experimental boiler, and, after numerous - trials, determined upon the form and dimensions to be adopted. - - In the consideration of these details, as indeed on all other - points affecting the success of this undertaking, I have not - hesitated to consult everybody whose opinions I considered - valuable, and to bring the result of their opinions in aid of my - own and the manufacturer's experience. - - I have only to add, that after giving much consideration to the - question of the diameter of the paddle-wheels and screw, I have - determined them sufficiently for fixing the position of the shafts, - and am now engaged in considering the best form and construction of - the propeller itself, and also the construction of the stern-frame - and rudder of the ship. - - The position of the paddle-shaft, and the diameter of the paddles, - have been questions of some difficulty. It being necessary to - provide for a considerable variation in the draught of water, - though not proportionably so great as with many existing large - steamers, and to balance well the relative advantages of securing - the highest average speed, at all the various draughts, or the - highest speed at a light draught, and to combine as far as possible - the two, so that the vessel may be as well adapted to perform - comparatively short and very quick passages to ports not affording - a great draught of water, as long voyages, heavily laden, at a - more moderate maximum, but still a large average rate of speed. - Although the full advantage of the great capacity of the vessel for - carrying coal for long voyages would not be felt in a voyage, for - instance, to New York, or in other short voyages, yet, - unquestionably, she would exceed all other vessels in speed and - extent of accommodation; and if it should be found desirable to - make such voyages, your vessels ought to be able to command almost - a monopoly by their superior capabilities, and I have therefore - endeavoured so to place the paddle-shaft, and so to construct the - wheels, that they may be adapted to the convenient application of - the full power of the engine at a light draught of water and at - very high speed. - - As regards the screw, the same points have to be considered, and a - choice made amongst the various forms and proportions more or less - successfully adopted at the present time. I have always found the - reports made upon the results of various forms of screws and - propellers, and the performance of different vessels, so little to - be depended upon, even when apparently made in good faith, and the - results obtained from good authority, that I have been long since - compelled to adopt no conclusion, unless from results witnessed by - myself or by persons observing for me. I have for some time past - availed myself of every opportunity that offered of observing and - obtaining something like accurate results upon the various points - affecting immersion of paddles or screw, and I am engaged in - considering those results. - - I have referred to the subject of protection from fire; it is one - of considerable importance, and I have some hopes that a process, - which has been recently patented by Lieutenant Jackson, may be - successfully applied to rendering wood uninflammable. Some door - panels have been already experimented upon with results which have - induced me to pursue the experiments, and I am about to try the - comparative inflammability of various qualities of wood, both - prepared and unprepared; and if we can succeed in preventing the - wood producing a flame, and thus communicating the fire; with the - numerous metallic subdivisions we shall have in the ship, the - spreading of fire, even from cargo or furniture, would become - impossible. I am also engaged in determining the character and - extent of mast and sail to be carried, as provision must now be - made in the construction of the ship for receiving the masts. - - The Directors are aware that I have been in communication with - Professor Airy as to the instruments which may be used in such a - ship, to ensure more accurate and frequent observations, and as to - the nature of these observations; an enquiry into which he has - entered with that liberality and desire to assist all improvements, - in navigation especially, for which he is so well known. Several - new instruments are now making for trials. - - Sir W. Snow Harris has promised to turn his attention to the - subject of the lightning conductors; and as soon as the iron work - is a little more advanced, and while the form and position of all - the principal masses are visible, the subject of local attraction - and the adjustment of the compasses will be considered by those - most competent to advise; and I am not without hope that the means - of correction may be rendered much more certain and perfect than - usual. I mention these, as some of the numerous points which - require and are receiving attention. - -In the last paragraph but one of this report Mr. Brunel mentions that he -proposed to adopt a system for obtaining continuous observations in -order to determine the position of the ship.[154] - -His first letter to the Astronomer Royal, which is dated as early as -October 1852, explains the object with which he began his -investigations:-- - - - October 5, 1852. - - You may possibly have heard of a project in which I am engaged, of - building some _very large_ steamboats.... Among the several - requirements, which it appears to me are involved in such a large - project, is one in which I hope for your advice and assistance, and - I trust you will consider the subject worthy of your attention. In - such a voyage, where so much depends upon perfect navigation, and - with such a capital at stake, no means can be too perfect and no - expense or trouble must be spared to ensure the constant - determination, with the greatest attainable accuracy, of the ship's - position and course. The determination of her speed, the effect of - winds and currents, and the variation of her compasses, together - with meteorological observations, are all involved in this; and I - propose to have an observatory and establishment of observers, - whose duty it will be to be constantly engaged, day and night, at - any moment when anything can be visible in the heavens, in taking - such observations as will determine more or less accurately, - according to the nature of the observations that the state of the - weather or other circumstances may admit of, the several points to - be ascertained. Now, the questions to be determined are, what is - the nature of the various observations that can best be made under - all the different, and the favourable and unfavourable - circumstances that may daily arise? what the instruments required, - and what the character and extent of the staff of observers - required; and even whether any, and if any what, new tables might - be useful for such a purpose? The primary object being to be - _constantly_ determining either correctly or approximately the - ship's true position, and in like manner _constantly_ checking the - compasses and giving her true course. I will not unnecessarily - expose my ignorance in such matters by stating what I have assumed - to be practicable. I will only remind you that experience proves - that in a vessel of such size there will be great steadiness of - motion, and therefore unusual facilities for accurate observation. - -Mr. Airy entered very warmly into the subject, as did also Professor -Piazzi Smyth, the Astronomer Royal for Scotland; and a long and -interesting correspondence passed between them and Mr. Brunel. -Experiments were conducted, principally with the view of obtaining a -stand for astronomical instruments by means of the contrivance known as -the gyroscope, the principle of which had been already adopted by Mr. -Brunel in a level designed by him in 1829. - -In connection with the observers' department, Mr. Brunel paid much -attention to designs of sounding apparatus and means for accurately -measuring the speed of the ship. He also intended to have a stream of -surface water constantly pumped up through the observers' cabin, which -should, by its change of temperature, immediately indicate the presence -of icebergs, instead of the plan of an occasional bucketful being hauled -up on to the deck according to the humour of the officer of the watch. - -Mr. Brunel made a very curious contrivance for enabling the man on the -look-out to keep his eyes open in a gale of wind. This consisted of two -sets of vertical plates of tin placed one behind another, diverging from -the direction of the wind, with a clear wide passage between the two -sets of plates. The wind, entering at the end of the apparatus, became -separated by the first two inclined plates, and the residue that passed -on in the direct line was again subdivided, so that at the end of the -last set of plates there was no rush of air between them, and a man -looking through the aperture, with his face to the wind, was in a -perfect calm. This was a useful arrangement, the look-out man's eyes -being as well protected as though behind a glass. A glass would not -answer the purpose, as it would become obscured with spray. - -The unfortunate circumstances which attended the completion of the ship -prevented the introduction of these and many other arrangements which -Mr. Brunel had originally proposed.[155] - -In November 1855, the Directors proceeded to appoint a commander to the -ship; and their choice fell upon Mr. William Harrison, one of the most -distinguished of the captains of the Cunard Company's steamers. - -This appointment gave Mr. Brunel great satisfaction; he found in Captain -Harrison a warm and faithful friend, and an able adviser on all matters -connected with the completion and equipment of the ship.[156] - -Before they came to a decision, the Directors asked Mr. Brunel to -communicate to them his views on the considerations which ought to -influence them in their choice. - -The memorandum he drew up on the management of the great ship, and a -letter on the duties of the chief engineer, are inserted at length, as -forming a complete record of the principles which, in his opinion, -should be followed 'in the use of this new machine,' while employed on -the voyages which she was specially designed to make. - - -_Memorandum on the Management of the Great Ship._ - - - October, 1855. - - The question of the principles to be followed in the use of this - new machine, for such it must be considered, and the character and - the qualifications of the man to whom it is to be entrusted, and - the points to which his attention must be particularly devoted, - have long been subjects of deep and serious consideration with - me.[157] - - And the difficulties are complicated by the consideration that - public opinion, and those established and universally received - opinions which, being the result of experience, cannot be called - prejudices, have to be considered, and must be yielded to to a - great extent, even when somewhat opposed to sound reasoning, or to - conclusions deliberately formed upon a due consideration of the - novel circumstances under which we have to act; but, while - conceding much to past experience, and to preconceived opinions, - the real requirements of the case must have the first - consideration. - - Thus, as it is a ship that we have to navigate, public opinion, if - nothing else, requires that we should have a sailor of undoubted - experience and skill to command her; but although seamanship may be - one of the essential conditions or qualifications for the - commander, I think we shall find, upon examination, that the work - we have to do, and the duties to be performed, and the - qualifications we consequently require in the man who is to conduct - this work, are so peculiar that mere seamanship, in the ordinary - sense of the term, if it were to be solely relied upon, would be - even a disadvantage rather than otherwise, and that we require much - that is not necessarily found in the most perfect specimen of a - seaman, and much that is far more difficult to find than the - ordinary qualifications. - - I wish particularly to impress this upon you: the subject has - occupied long, frequent, and serious deliberations. I have come to - the conclusion which you will no doubt readily acquiesce in, that - our first practical mechanical success, upon which so much of our - financial success hangs (although others might reap the benefit - even of our failure in the first instance), will depend mainly upon - the skilful management in our earliest voyages of the machine we - are about to set afloat; but I have also come to the conclusion, - the correctness of which may not be so immediately apparent to you, - that this machine, though nominally a ship, not only admits of, but - requires, a totally different management from that which may have - successfully navigated ordinary ships, and that most of the habits, - feelings, and sensations, amounting to instinct, possessed by a - good sailor, and the peculiar power of skilful adaptation of - expedients to emergencies, which constitute the merits of a - first-rate sailor, have to be put aside for a time rather than - applied in the first instance to make a successful commander of the - vessel. - - In navigating a small vessel, a man has to study the appearance of - the weather, the direction of the wind, and that of the seas; to - consider the probabilities of change; to vary his course more or - less with reference to any of these causes, and according not only - to the then state of all these operating causes, but also with - reference to the probabilities of change; and with their - consideration his mind is principally occupied, and it is in the - exercise of judgment and foresight in these points that he shows - his skill. - - Steam navigation, and the gradual increase in the size of vessels, - have no doubt materially modified this, but much still remains to - occupy the mind of the commander of a steamer, with which not only - we shall have nothing to do, but too much attention to which, from - previous habits, would divert his attention from that which, under - the different circumstances, will become much more important. - - In the same manner, in manoeuvring such a vessel in harbour, the - ordinary modes would be totally inapplicable; whereas, by entirely - discarding all previous practices, and keeping in his mind and - making use of the peculiar powers which are at command in this - vessel, and judiciously attending to the immense effect of the _vis - inertiae_, or momentum of such a mass, so far beyond that of - anything now afloat that it becomes a totally _new_ influence, this - machine may be managed by a skilful man with a facility which is - not attainable with small craft; while such a mass would be - destruction to itself or to anything that comes in contact with it, - if treated at all in the same manner as even the largest steamers - are now handled. - - Another peculiarity to be attended to in the management of this - mighty mass is that by no possibility must she be allowed to touch - the ground. - - Our ship will be found, I believe, if tried, to possess unusual - strength: no combination of circumstances within the range of - ordinary probabilities can cause such damage to her as to sink her, - even if she were to be run on sharp rocks with deep water around; - and I believe she might remain for months aground, exposed to the - heaviest seas without serious damage. The lives of the passengers, - and even the cargo generally, will be safe, almost perfectly safe, - and so far she will be very different from and very superior to any - vessel now afloat; but there will also be another great difference, - although she may remain safely aground, she will probably remain so - for a long time. - - If she were to ground at high water or where there is a little - tide, and when she happens to be rather light of coal, and should - take in any water so as to deepen her, no ordinary appliances in - the power of the crew will get her off, or, at all events, not - without great loss of time, and at very heavy sacrifices. Such an - event in the first year of her career would probably ruin our - Company, as the grounding of the 'Great Britain' did the Great - Western Steam-Ship Company, although it proved the good qualities - of that ship, and thus advanced iron ship-building. A sailor will - no doubt receive with disgust and as an insult the suggestion of - the possibility of his running his ship ashore. We cannot afford, - however, to rest contented with this expression of feeling, natural - and praiseworthy as it may be: our circumstances are totally - different; and that which is considered certainly as a serious - evil, but still only an evil more or less serious, would be to us - fatal; it is no longer a question of degree of injury--it is death. - I have had some costly experience; I have had to do with many - steamers--several remarkable for their size and their value, - according to the ideas of the time, and two of them each in their - day considered Leviathans, more wondered at than even ours, and - exciting much more anxiety on the part of their promoters, and - there was as much care taken in the selection of commanders as I - ask you to take now; nevertheless both of these, to the ruin of the - Company in one case, and almost every other steamer I have had - anything to do with, has not merely touched, but been aground. Not - a season hardly passes without a case of even a Queen's ship going - ashore, although navigated by men educated for the purpose, with - the advantage of every appliance hitherto thought necessary and - sufficient, and with fearful responsibility attached to them. All - these are published cases known to the world; and if the log books - of all the steamers were searched, I believe the result would be a - list in which the ships that had not been aground would form the - exceptions, and, in the majority of cases, the blunder is so gross, - that the most far-fetched excuses of errors of compass and unknown - currents, although in well-known channels, are obliged to be - invented. - - The real explanation is a simple one. Ships are navigated with far - too reckless a confidence in the mere personal instinct and skill - of those in command, and in their ability to get out of a scrape in - time. Methodical systems and mechanical means of ensuring accuracy - are far too much neglected, or rather have not kept pace at all - with the great improvements in speed and the power of locomotion - which science has introduced, whether in the construction of steam - vessels or even of sailing ships, and which the advance of the day - now calls for. There are no means at present used of taking - soundings worth having while a ship is going fast through the - water, or in time to be of any use if the soundings shoal rapidly; - the trouble is so great and the operation so slow that it is not - resorted to sufficiently often. The steering by compass is so rough - and so coarse, that no real accuracy is attained. Good observations - to determine position are taken at too long intervals of distance - run, and consequently are subject to be interrupted for too long a - period by what is called and supposed to be continual bad weather; - although it would rarely happen, if persons were continually on the - watch, who had nothing else to do or to think of, that twenty-four - hours would pass without some glimpses of a star or of the sun. - Thus with a speed of ten or fifteen knots, and cloudy weather, and, - above all, with that unfortunate confidence of seamen to which I - have referred, there is never any certainty just at the time when - it is really required. No doubt, skilful seamen do generally arrive - at an astonishing approximation in their estimates, and the results - on the average are most successful, and remarkable proofs of the - skill brought into action. But the instrumental means of attaining - accuracy are lamentably in rear of the improvements that have been - made in the means of locomotion, and have not at all kept pace with - the vast increase of capital embarked in each individual case. - - All these deficiencies are, however, easily remedied; the means do - exist, or can be devised, and might be applied if we insisted on - their application. We have seen numerous instances where the - difficulties are admitted and grappled with systematically, and - with what patience and skill a fleet has been piloted up unknown - rivers full of shoals in China, and through intricate channels with - covered rocks in the Baltic. In our case, the object to be attained - is a vital one to us; and what I most dread is the confidence of - our commander resulting from his previous experience preventing his - appreciating the peculiarities of the case, and applying that - greatly increased amount of method and system which is essential to - change that, which is now rendered only highly probable by the - skill of man, into mechanical certainty. The man who takes charge - of such a machine, in which is embarked so large a capital, must - have a mind capable of setting aside, without forgetting, all his - previous experience and habits, and must be prepared to commence as - an observer of new facts, and seize rapidly the results. A man of - sense and observation, with a good mechanical head, and with - decision and courage, would succeed without much previous nautical - knowledge; but, unquestionably, a man familiar with all that is - going on around would be much more competent, provided he does not - allow his habits derived from former experience to induce him to - neglect any of the new means of information in his power, to all - which his former knowledge should be made subservient. - - If much has to be unlearnt, or rather carefully set aside for the - time, as generally inapplicable in its present shape, there is also - much to be learnt in the navigation of such a vessel; and one of - the most essential qualifications of the commander would be a - belief in his want of experience, and a readiness to see the - novelty of his position, and a cautious and sound but quick - perception of the new and powerful influences and _new_ effects of - those same causes with which he may have been familiar under very - different circumstances. - - The great mass and size of this vessel must necessarily render it - so much less affected by the ordinary disturbing causes of wind and - sea, that, practically, little attention ought to be paid to these, - at least not as expecting the ordinary results; but other effects - may be produced which must be carefully studied and learnt in the - early voyages, so that they may be met and counteracted as they - have been by experienced men under the present system. Thus, as an - example of this class of effects to which I would refer, there is - reason to believe that this vessel, although apparently unaffected - by a wind on the beam, or a cross sea, which would be very - noticeable even with the largest of the present steamers, would - nevertheless have a steady and rather strong tendency to come up to - the wind. A certain direction of a cross sea is not unlikely to - produce a contrary effect. It is quite possible also that the - apparent lee-way, or the deviation of the axis (or keel) of the - ship from the line of the course, will be greater with the wind on - the beam than with smaller vessels, although the actual drift or - lee-way may be less; and all these effects will result from her - great length (unless counteracted by causes I do not now foresee), - and will probably be totally different in degree from any similar - effects now felt. These effects must be carefully studied, and with - a mind prepared to consider them as new, for they will be new and - distinct from anything now experienced. In the same manner, and to - a much greater degree, the effects of the speed which we must hope - to attain will upset all the usual methods of determining - accurately the position and the course of the vessel, and still - more the precautions to be taken in approaching land. A 24 hours' - run, at 20 miles per hour, without a good observation, and with a - possible error of estimate, or a doubt, at all events, of the exact - effect of the set of currents, or of the speed of the ship through - the water, or of the precise amount of lee-way, may easily make an - error of 20 or 30 miles in position at the end of the day's run. - - On the other hand, by almost abandoning the present modes, and - adopting measures which I shall point out presently, adapted to the - new circumstances, a much greater degree of certainty and accuracy - may be attained than is now even sought for. I have had the best - advice on these points, both astronomical and nautical: the - Astronomer Royal, Mr. Airy, who both as a man of science and a - practical man, and by his official position, is the first authority - on such matters, and Professor Smyth, of the Edinburgh Observatory, - Captain Beecher of the Admiralty, and several other scientific - naval men, have assisted me; and, under their advice, instruments - are being constructed, and a system devised, which will admit of - continuous observations being made with great accuracy at all times - of the day, and particularly at night, and by means of which also a - continuous correction of the ship's compasses with the most minute - accuracy can be kept up, and her position be ascertained with - almost the same accuracy as a point on land; and I have their - authority for saying that such improved means are desirable, and - are attainable. - - The importance and advantage of continuous observation throughout - the twenty-four hours, whenever a glimpse can be obtained of any - object which will answer the purpose, and even when the horizon is - invisible, may not at first be evident, but it cannot be - over-estimated. An exact knowledge of the ship's movements will be - soon acquired that would almost replace observation, and the - average of numerous observations secures an accuracy which cannot - be approached by any other method. - - By a careful and continuous comparison of the exact distances run, - with accurate records of the speed of the engine and of the ship - through the water, registered by good instruments (the performance - of which has been tested, and which are being made), and having - proper reference to the varying draught of water of the vessel, the - most precise measure of the speed of the vessel through the water - can be learnt; and by careful observation of the force and - direction of the wind, the effect of any given wind, and an - accurate measure of her drift or lee-way, may be obtained; and - then, by adhering strictly, without regard to wind or weather, to a - course previously laid down on good charts, having upon them the - sets of currents, as already observed, the true position of the - ship may be determined at any moment, and there need never be the - slightest hesitation, or any time or distance lost by doubts. - - In addition to the instruments above named, I hope to be able to - provide the means of sounding at moderate depths while the ship is - going her full speed. - - Having the means, then, of determining the ship's course and - position with much greater accuracy than is now practised, we must - seek to make that course, or the distance to be run, the shortest - possible, that is to say, the course which will occupy the least - time. - - The exact course to be taken by such a vessel must be determined - upon and laid down upon the charts after a due consideration of all - the circumstances which can possibly affect the time occupied in - the voyage between any two points, and particularly by examining - and considering well all the information which scientific observers - have collected and recorded as to the currents, probabilities of - fogs, or of ice, and other impediments, the chances of meeting - vessels, which must be avoided as much as possible, the average - direction of prevailing winds, varying such course, perhaps, in - certain latitudes with the season of the year, but certainly not - with the temporary direction or force of the winds or state of - weather at the moment; for the speed which we shall attain renders - these causes of secondary consideration, and would interfere with - all ordinary calculations derived from present experience of the - probable state of the wind in the new position which the ship would - attain after a few hours' run. The business of the commander would - be, therefore, to adhere rigidly to the exact course previously - deliberately determined upon, and not to be tempted to deviate - except slightly, and even then only according to rules which he - shall have previously laid down for himself. - - The importance of adhering strictly to this rule cannot be - over-estimated. The period occupied in a voyage will be materially - influenced by the exact course followed, and as such course must - be determined upon only by a calm and somewhat laborious study of - documents, it cannot be safely determined upon except in the - closet, that is, _before the voyage_, and uninfluenced by the - excitement of hopes or by disappointments caused by difficulties. - - The safety of the ship and of the enterprise may also mainly depend - upon the rigid adherence to this rule. - - With the means at his disposal for checking that course, and with - the method and regularity involved by a rigid adherence to it, and - a correction at once of any departure from it, a degree of - certainty will be attained as to the ship's position which will - almost preclude the possibility of an accident, and which I - consider practically invaluable as affecting the safety of our - vessel. This rigid adherence to an exactly prescribed course will - prevent any risk of that which is the cause of the greater number - of losses. No inducement of fine weather, or a happy state of mind - and body of the captain, or a desire to save time, or to show the - beauties of a coast, or any other temporary cause, will lead to a - nearer approach to dangerous points than had been previously - determined upon as safe. The shortest and best route, the safest - from all dangers, and giving the widest berth to all shores or - shoals, having been laid down, must be kept to against all - temptations. - - Economy of fuel is another consideration of the highest importance. - The engines are of power sufficient, if fully worked, to consume - considerably more than the cargo provided. Large as may be the - supply which the ship is capable of carrying, it is no more than - that which is calculated as necessary for the voyage intended, with - a moderate allowance for contingencies; and it must be borne in - mind that the ordinary means of making up any deficiencies would be - totally inapplicable in our case, since no supply capable of being - drawn in an emergency from other sources would be sufficient. - - The precise quantity calculated and provided must be made - sufficient, or the consequences would be serious. The usual - practice, therefore, of going ahead as fast as the engines will - take the ship must be entirely abandoned. Careful observations, - systematically pursued, will show the speed which, under different - states of immersion, can be attained without a disproportionate - expenditure of power, and to this speed the engines must be - limited. A little experience will probably show that, under certain - circumstances of immersion of the ship, or of the state of the sea, - it may be economical to force the screw or the paddle engine, the - one more than the other. This can only be determined by somewhat - delicate and very precise and accurate observations. These must be - made. It is not merely a question of degree, but our whole success - depends upon the application, not of one, but of all these - refinements. - - A close study of the relative speed of the ship, as ascertained by - the self-registering logs, and by continuous astronomical - observations, compared with the expenditure of power in the engines - as indicated by the number of revolutions constantly registered, - and the power expended as measured and recorded by the chief - engineer, will be necessary for some time to come, and until indeed - the management of such large ships becomes as much a matter of rule - as it is now, or perhaps ought to be more than it is, with smaller - ones. - - As to the use of the sails, while the engines are nevertheless in - full action, it must be entirely a matter of experiment, and an - experiment in which, again, all previous habits and prejudices must - be set aside. - - Whether a sail steadies such a ship usefully or not can be, and - must therefore be, positively determined by measurement with proper - instruments, and not by the sensations; and the result upon the - speed of the vessel as compared with the power expended must, in - like manner, be ascertained by positive observations and - measurements. No past experience can do other than mislead. It is - quite possible that the same means which improve the rate of the - present large steamers may be prejudicial to our performance. - - The commander must appreciate the necessity of all this study and - attention to what is rather mechanical than nautical, or our voyage - will be a failure. The difference between the peculiar qualities of - such a floating mass as compared with those of the largest steamer - now afloat, is likely to be as great as between the last and a - 100-ton cutter; and the most prejudiced believer in the acquired - skill of an old sailor who had learnt to manage the small vessel in - the most perfect and masterly manner, would not expect him to be - able to handle one of the present large steamers, still less to - elicit the best performance out of her. In the same degree the man - who takes the command of our ship must, if he is to succeed, enter - upon his duties with a belief that he has nearly all to learn, at - the same time that this feeling is perfectly consistent with a - proper confidence in his own powers to master the new - circumstances, and to succeed with this as he may have done with - other vessels. - - Finally, the commander's attention must be devoted exclusively to - the general management of the whole system under his control, and - his attention must not be diverted by frivolous pursuits and - unimportant occupations. I believe that even in the present large - steamers much advantage would result from relieving the captain - from all care of the passengers and cargo; but in our case, where - we may have to provide for thousands instead of hundreds, and - arranged in different classes, and living in completely separate - saloons and compartments, the present system of a captain dining at - the table and associating with the passengers would be - impracticable, even if it were desirable. But for much more - important reasons, and on general grounds, I think that while the - commander is of course supreme over every department, he should not - be embarrassed by undertaking any one, still less should he have - his mind occupied with the troublesome and frivolous concerns of a - vast hotel, nor should he be hampered by the necessity of attending - to the hours and the forms of a large society. Moreover, I consider - it essential that he should by his presence and control keep up the - position and the sense of responsibility of the chief officers - under him, by living and messing with them; the commander and those - acting immediately under him must occupy a more dignified position - than they now do. - - The result of all these general views is, that the command of this - ship must be considered to consist mainly in the superintending and - keeping up in a high state of order the perfect working of a highly - methodical pre-arranged system, by means of which the ship is to be - made to go like a piece of very accurate machinery, precisely in - the course which has been pre-arranged, and precisely at the speed, - and with the consumption of power, which has been ascertained to be - the highest attainable with the requisite economy; and there must - be a proper establishment of assistants, competent to control each - department of this system. As regards the constitution of this - establishment, I consider the commander should have a staff of - chief officers or captains. I believe three will be necessary, with - a fourth performing general duties and ready to take the place of - any one of the three; that one of them should always be in command - of the ship (under the commander); that, besides these chief - officers, there should be a master, corresponding to a master in a - Queen's ship, who would have assistants and calculators or clerks, - whose duties would be to keep the ship's reckoning, to keep up - perfect and continuous observations, to calculate with precision - and set from hour to hour the exact course by compass which has to - be followed, to keep in the course determined upon by the captain, - to keep a series of accurate observations and records of all - matters that can affect the ship's movements--duties involving an - amount of science and practical astronomical and mathematical - knowledge which requires a superior education, and which is found - only in this class of men. The duty of the master would be - therefore to supply the science necessary for the conduct of the - ship, and to be the commander's cyclopaedia and book of reference, - to be able at any moment to report to the commander the exact - position of the ship and her course, and the variation of her - compasses, and take the soundings, if any, to note the fact of a - change in the temperature of the water, indicating approach of ice, - and any other symptom or fact which can affect the ship's - movements--all which should be determined by continuous - observations methodically and mechanically made, and not be - dependent upon the chance of the commander's anxiety or greater or - less forethought. The chief engineer should also be a superior man, - selected more for his general qualifications as a good director of - men and machinery, than as a mere marine engineer. These should - form a staff, and be of a standing to live and mess with the - commander; so that each department should thus be furnished with a - chief competent for the special duties of his department, and - reporting to and acting under the general control of the commander. - - That the principles thus laid down as to following exactly a - prescribed and predetermined course, and as to regulating exactly - the consumption of power and consequently of fuel, and the keeping - up a system of what may be termed scientific observation for the - purpose of ensuring this regularity, I submit should be rigidly - enforced; and the commander should be required to adopt these - principles as the guide of his conduct, and to use the measures - that are placed at his disposal for working this machine in the - manner and with the precision pointed out. - - -_Letter on the Duties of the Chief Engineer._ - - - March 19, 1857. - - The duties which I apprehend will devolve upon the chief engineer - of our ship will be, firstly, the supreme direction and management - of both the principal engines, and all the auxiliary engines and - machinery worked by them in the ship; and as the construction of - such a ship, and of many of its adjuncts, such as the iron masts - and yards, steering apparatus, and other parts, are strictly of an - engineering character, and such as in the event of repairs, - particularly at sea or in foreign ports, would require a mechanical - engineer rather than a shipwright, I think it must be made part of - your duty, as the most competent officer, to make yourself - thoroughly acquainted with the construction of the ship and all its - parts, and all mechanism within it, so as to be prepared to take - such share of responsibility as to the state of the structure of - the ship as it may be found desirable to throw upon you as chief - engineer, and at all events to be prepared to be the captain's - chief authority and responsible adviser on all matters of - mechanical engineering. - - The principal duty, however, will of course be the management of - the engines, including the care of the paddle, screw, and other - machinery immediately connected with the engines, or worked by - them; and as the success of the ship as a steamboat will depend - entirely upon the amount of power developed by the engines, in - proportion to the fuel consumed, there is no limit to the degree of - attention, of judgment, and of skill, that not only may be usefully - applied, but that must be applied to ensure success. - - I have no wish to alarm you as to the amount of work or - responsibility that will devolve upon you; my object is rather to - show you the opportunity afforded of displaying judgment, skill, - and assiduous attention, and thus, as I hope, to excite your - ambition, when I seek to draw your attention very strongly to the - peculiarities of this case. - - In ordinary steam navigation, whatever perfection has as yet been - sought for or attained, the business of the engineer has been - mainly to keep the engines in perfect order, and to develope the - greatest amount of power possible, and, secondly, to effect as - great economy as possible in the consumption of fuel; but the - latter has been merely a question of economy in a pecuniary point - of view, and not of necessity, and has been entirely secondary to - the first condition, so much so that the most successful ships have - not been by any means the most economical, on the contrary, they - have been rather extravagant consumers. - - In the present case, the circumstances are totally different, and - it will be essential that you should change altogether your - accustomed views on this subject. - - This ship is built to go round the world with a defined and limited - amount of fuel, which you have no power to exceed, or rather, if - you exceed it, at any part of the voyage, the whole is a failure. - The circumstances are therefore reversed, with this additional - condition, that there is no medium or partial success. In the - ordinary cases you have a limited power of engine and an excess of - fuel, in which it is desirable but not essential that you should - effect economy; in the present case you have a limited and defined - quantity of fuel to consume, with an excess of engine power, and - the art will be to obtain the largest total amount of power from - this fuel, expending it progressively, and in such a manner as to - reach a given point. To effect this, and obtain the best possible - results, will require of course that the engines should be kept in - the best possible order; but this, although a preliminary - condition, is an ordinary one, requiring no peculiar duties or - exercise of judgment, and must be assumed, as on all occasions, a - matter of course. The peculiar duties in our case will be the - continuous study in every trifling detail that can effect the - result of the means of obtaining the largest amount of steam from - the defined expenditure of fuel and the use of this steam, so as to - obtain the largest amount of power, and the largest amount of - result. - - The mere study of this question must necessarily occupy some time, - and for several voyages it will be a subject of experiment; but the - more rapidly positive information can be obtained, the more prompt - and certain will be our success. To attain success will require a - degree of attention to every minute detail, which it has never yet - been necessary or profitable to devote to this branch. - - The continuous weighing out of coals and measure of the products of - each boiler (for which means will be provided), the continual - observation of the extent to which blowing-off is desirable, the - continuous measure by indicator of the performance of the engines - under different pressures and degrees of expansion, so that you can - at all times furnish the captain with the exact performances of the - two engines, and the cost of fuel required to produce given results - in each; so that he may have the means of comparing your - expenditure with the results he obtained in the speed of the ship, - and of learning the relative beneficial effects of employing more - or less the paddle or the screw in different states of weather, or - different immersions of the ship, will be required; and every - method of increasing the performance of each gang of stokers, and - of stimulating their skill and care, and every refinement in each - separate branch of the work, to effect economy of fuel, or rather, - development of power with a given amount of fuel, will be - necessary. We all know full well how, if every effort is - continuously made and every possible care is continuously bestowed - in each department, 4 or 5 per cent. can be saved or gained in many - points, and at many times in the 24 hours, between the drawing of - the coals from the bunkers and the development of power at the - paddle board or the screw blades; and if only 1 per cent. can be - thus gained in a few points, the aggregate will soon amount to 10 - per cent., which with us may make the difference between success - and failure. All these things will require judgment, thought and - attention, rather than labour, and, above all, close watching and - method, and good management of men. - - Besides these more than ordinary duties during the voyage, the only - peculiarity in the service will be that, with such a costly - machine, the mere interest of money and fixed expenditure upon - which will not be short of 200_l_. a day, and the perfect state of - which is so essential, you will be required to give more attention - to the machinery when in port than is usually required. - - I trust that this strong but not exaggerated statement of what - would be expected of the chief engineer, will excite your desire to - undertake the duties, rather than deter you from seeking the post; - and that, if the Directors should accept the offer of your - services, you will enter upon the duties with confidence, though - with a sense of their serious importance. In the event of your - appointment, it will be a necessary condition that you should be - able to commence at once the supervision of the erection of the - engines. This work is already much farther advanced than I should - have wished it to be before the chief engineer had taken charge of - it. I attach great importance to his having that familiar knowledge - of all the parts and their condition, which no study of drawings - can give so well as actual inspection during erection, and I wish - also that he should satisfy himself of the perfect truth of every - adjustment. - -It will be seen from the documents which have been printed in this -chapter how 'deeply and seriously' Mr. Brunel had considered all the -conditions which were, in his opinion, necessary for the economical -construction, and the successful employment, of the great ship; but it -is hardly possible, by means of extracts from his correspondence, to -convey an adequate impression of the amount of labour he expended--from -the year 1852 to the last days of his life--on the supervision of every -detail of the work. 'The fact is,' he said, 'I never embarked in any one -thing to which I have so entirely devoted myself, and to which I have -devoted so much time, thought, and labour, and on the success of which I -have staked so much reputation.' - -Heavy as Mr. Brunel's duties were in October 1854, when he wrote these -words, a far greater amount of labour was subsequently imposed upon him. - -During the year 1855 financial difficulties arose which interfered with -the progress of the ship; and at last, in February 1856, although Mr. -Brunel had done everything in his power to prevent the necessity of such -a step, the works were suspended; and they were not resumed till the end -of May, after which date they were carried on by the Company under the -supervision of the existing staff. It was greatly against Mr. Brunel's -wishes that this was attempted, except as a temporary measure, as he -considered it impossible for a company to carry on such a work -efficiently and economically. - -Notwithstanding all these difficulties, that which seemed at first only -a confused mass of iron assumed by slow degrees the graceful proportions -of a 'great ship'; and the hull of the vessel was completed by the end -of the summer of 1857, so far as it was desirable to proceed before the -commencement of the launching operations. - - - - -CHAPTER XII. - -_STEAM NAVIGATION--THE 'GREAT EASTERN' STEAM-SHIP. THE LAUNCH._ - -A.D. 1857--1858. AETATIS 52. - - REASONS FOR DETERMINATION THAT THE SHIP SHOULD BE LAUNCHED - BROADSIDE TO THE RIVER--AND THAT THE LAUNCH SHOULD BE - SLOW--EXTRACTS FROM MR. BRUNEL'S REPORT OF FEBRUARY 1855--REASONS - FOR THE ADOPTION OF IRON SLIDING-SURFACES--DESCRIPTION OF THE WAYS - AND CRADLES--AND OF THE MOTIVE POWER PROVIDED FOR LAUNCHING THE - SHIP--MEMORANDUM ON PROPOSED ARRANGEMENTS FOR THE LAUNCH (SEPTEMBER - 26, 1857)--LETTER TO CAPTAIN HARRISON ON RIVER TACKLE (SEPTEMBER - 30, 1857)--LETTER ON THE NATURE OF THE OPERATIONS (OCTOBER 23, - 1857)--MEMORANDUM ON GENERAL ARRANGEMENTS AND INTENDED MODE OF - PROCEEDING (OCTOBER 30, 1857)--HISTORY OF THE LAUNCH, NOVEMBER 3, - 1857-JANUARY 31, 1858--LETTER TO THE DIRECTORS, NOVEMBER 26, - 1857--REPORT AND MEMORANDUM ON THE LAUNCHING OPERATIONS (DECEMBER - 17, 1857)--FLOATING THE SHIP--_NOTE A_: EXPERIMENTS AND - OBSERVATIONS ON FRICTION.--_NOTE B_: LETTER TO W. FROUDE, ESQ. - (FEBRUARY 2, 1858). - - -The mode in which, the great ship was to be launched had necessarily to -be determined before she was commenced. In May 1858, when the contract -for her construction was entered into, the question was left open, and -the contractor was either to launch her, or to build her in a dock 'if -it be found preferable.' With Mr. Brunel's full concurrence, Mr. Russell -determined to build the ship on the river-bank, broadside to the river. - -The reasons which led to this determination were fully described by Mr. -Brunel in his report of February 5, 1855. This report has, with the -exception of the parts relating to the launching operations, been -printed above, p. 315. The passages there omitted are as follows:-- - - One of the first points to be decided was the mode of launching the - vessel, which of course would determine the position in which it - was to be built; and I wish to take this opportunity of explaining - my reason for adopting the plan I have decided upon, which, being - unusual, might be supposed to be unnecessary. - - Vessels are generally built above the level of high water, and then - allowed to slide down an inclined plane into the water; - occasionally, as in the case of the 'Great Britain,' they are built - in a dry dock, into which the water is afterwards admitted, and - they are floated out. - - Both plans were well considered in the present case; but the size - of the dock required, the difficulty of finding a proper site for - such a dock, the depth required for floating a ship with her - engines and boilers, which it was most desirable to introduce while - building the hull, and the depth of channel required to communicate - between such a dock and the deep water of the river, all combined - to render the dock plan a very expensive, and, considering the - nature of the soil in which it would have to be formed, a somewhat - hazardous proceeding. Launching seems to offer the fewest - difficulties and the greatest certainty; but the dimensions of the - vessel required some modifications of the usual modes of - proceeding. - - Launching is generally effected by building the ship on an inclined - plane, which experience has determined should be at an inclination - of about 1 in 12, to 1 in 15, the keel of the ship being laid at - that angle, and the head consequently raised above the stern, say - one fifteenth of the whole length of the ship. In the present case - this would have involved raising the fore part of the keel, or the - fore-foot, about 40 feet in the air, and the forecastle would have - been nearly 100 feet from the ground; the whole vessel would have - been on an average 22 feet higher than if built on an even keel. - - The inconvenience and cost of building at such a great height above - ground may be easily imagined; but another difficulty presented - itself which almost amounted to an impossibility, and which has - been sensibly felt with the larger vessels hitherto launched, and - will probably, ere long, prevent launching longitudinally vessels - of great length. The angle required for the inclined plane to - ensure the vessel moving by gravity being, say 1 in 14, or even if - diminished by improved construction in ways to 1 in 25, is such - that the end first immersed would become water-borne, or would - require a very great depth of water before the forepart of the ship - would even reach the water's edge. Vessels of 450 or 500 feet in - length would be difficult to launch in the Thames unless kept as - light as possible; but our ship could not be so launched, the heel - of the sternpost being required to be, as I before said, about 40 - feet below the level of the fore-foot. Some mitigation of the - difficulty might be obtained by an improved construction of the - ways; but the great length of ways to be carried out into the river - would, under any circumstances, be a serious difficulty. - - These considerations led me to examine into the practicability of - launching or lowering the vessel sideways; and I found that such a - mode would be attended with every advantage, and, so far as I can - see, it involves no countervailing disadvantages. This plan has - been accordingly determined upon, and the vessel is building - parallel to the river, and in such a position as to admit of the - easy construction of an inclined plane at the proper angle down to - low-water mark. - - In constructing the foundation of the floor on which the ship is - being built, provision is made at two points to ensure sufficient - strength to bear the whole weight of the ship when completed. At - these two points, when the launching has to be effected, two - cradles will be introduced, and the whole will probably be lowered - down gradually to low-water mark; whence, on the ensuing tide, the - vessel will be floated off. The operation may thus be performed as - slowly as may be found convenient; or, if upon further - consideration more rapid launching should be thought preferable, it - may be adopted. - - I have entered at some length into an explanation of all the - reasons which led to the adoption of this plan; as I am anxious - that they should be known, and particularly that it should be well - understood by the proprietors and those interested in our success, - that I am not adopting any novelties; unless, so far as those - modifications of the more usual practices which experience points - out as necessary to meet the peculiarities of a particular case may - be deemed such. - - I should add that the necessity, arising from the same causes, of - launching transversely has been felt with long vessels of another - description, namely, pontoons, or floating piers; one of 300 feet - in length, which I have built at Plymouth, was so launched, and - previously to this, one of 400 feet in length by Mr. Fowler on the - Humber.[158] - - I hope to be able to arrange that the machinery, which is to be - provided by the contractor, for lowering the vessel down the ways - will be also fitted to form a 'patent slip' arrangement for hauling - the ship up for repairs; so that, if it should be found desirable - to do so, such apparatus may be purchased for that purpose, and - fitted up at the port which the ship will frequent. With the view - of facilitating such an operation, or the grounding of the ship on - a gridiron for examination at low water, a sufficient extent of the - floor of the ship is formed perfectly flat, and is so strengthened - as to allow the ship when loaded to be grounded without being - unduly strained. - -After it was determined that the ship should be built on the river-bank -instead of in a dock, and parallel to the river instead of at right -angles to it, the next point for consideration was, whether the ship -should be lowered gradually to low-water mark, or whether a free launch -should be attempted. - -In a free launch the ship is allowed by the action of the force of -gravity to run down the ways at a considerable velocity. In the case of -the 'Great Eastern' there were insurmountable objections to this plan. -Some of them might have been overcome by mechanical appliances; but -these would have introduced complication and additional elements of -risk. - -In accordance with the opinion which he had from the first entertained, -Mr. Brunel determined to move the ship slowly down the ways. - - * * * * * - -Subsequently to his determination to launch slowly, Mr. Brunel decided -to employ sliding-surfaces of iron instead of greased wood. - -In ordinary launches the ways are thickly greased, so that there is -between the ways and the cradles a thick stratum of grease, which -renders the friction very small. The conditions, however, do not remain -the same throughout the passage of a ship down the ways; for, when she -has moved some distance, the cradle has been rubbing away and squeezing -out the grease; and therefore the part of the cradle which supports the -middle and bows of the ship meets with increasing resistance from -friction. Another and more serious cause of the destruction of the -lubrication arises from unevenness in the ways. - -The result of the action of the friction between the wooden surfaces -after the destruction of the grease is sometimes so great that they -become mutually imbedded, the fibres of the wood being rolled up -together to such an extent that it has been found difficult afterwards -to separate the timbers. The increased friction due to the deterioration -of the sliding-surfaces of grease does not often produce failure in -ordinary ship launches, because the vessel, while still on the fresh -grease, acquires a momentum sufficient to carry it over the lower part -of the ways, notwithstanding the retardation resulting from increased -friction. - -It was from a legitimate fear of the development of a retarding force -due to the destruction of the grease, that Mr. Brunel hesitated to -employ wooden sliding-surfaces. The ground was far from solid; and the -use of piles as a foundation for the ways would not have prevented the -possibility of excessive local pressure being brought on parts of the -surfaces. The heat produced by undue pressure at any point under the -great area covered by the cradles would tend to spread and aggravate the -evil; and, had any considerable portion of the sliding-surfaces become -wood-bound, the difficulty would have been far less remediable than in -the case of an ordinary launch, where the cradles and ways are -throughout accessible. But in the case of the 'Great Eastern' the space -between the ship and the ways, over a considerable portion of the area -covered by the cradles, was very confined, and it would have been a -most tedious, if not a hopeless, task to get at the injured part so as -to repair it properly. - -At the end of the year 1856, when the construction of the ways had to be -commenced, Mr. Brunel acted upon his views as to the dangers attendant -on the use of wooden sliding-surfaces, and adopted iron. By this step, -although there might be some fresh difficulties to be encountered, the -disastrous consequences were avoided which might have followed from -employing wooden surfaces. - - * * * * * - -Under two places in the length of the ship the ground had been prepared -for the reception of the launching ways. These ways or inclined planes -were two in number, and reached to low-water mark. They were placed at -such positions as best to carry the weight of the ship without straining -her. The ways, as originally designed by Mr. Brunel, were each 80 feet -wide; but, with the desire of spreading the weight of the ship over a -still larger area, he decided to add 20 feet to each side of each way, -thus increasing their breadth to 120 feet. The ship's head pointed down -the river; 180 feet of the bow projected beyond the forward way, 110 -feet were unsupported between the two ways, and 150 feet of the stern -projected beyond the after way. The distance from the starboard side, -the side next to the river, down to low-water mark, was about 240 feet; -and the actual length of the ways, including the portion under the ship, -was about 330 feet. - -At the same time that he decided to use iron as the sliding-surface, Mr. -Brunel adopted means for ensuring, as far as possible, the even -distribution of the weight upon the ways. With this object he did not -attempt to make them unyielding, but allowed them to yield slightly, so -that, like a cushion, they might adapt themselves to the under surface -of all parts of the cradles with a sufficient upward pressure. The ways -rested on the river-bank, and piles were used to prevent the earth under -the edges of the ways from swelling out at the sides, and yielding more -than the ground under the middle portion. - -The ground having been prepared to the slope of 1 in 12, a layer of -concrete of about two feet in thickness was laid over the area of the -ways. On the concrete were placed timbers running at right angles to the -ship. These timbers, which were imbedded in the concrete, were 1 foot -square, with a space of 2 feet 6 inches between them. Across these -timbers, and parallel to the ship, were placed other timbers, with -intervals of 2 feet between them; and upon these again were laid rails -18 inches apart, parallel to the ways, and at right angles to the ship. -The rails were of the ordinary kind used on the Great Western Railway. - -Thus the ways consisted of a network of timber resting on a thin bed of -concrete; and on the top of the timber network were placed the rails -which formed the actual sliding-surface. - - * * * * * - -The under side of the cradles consisted of iron bars, which were laid -parallel to the ship, and therefore across the rails of the ways. These -bars were each 1 inch thick and 7 inches broad, with an interval of 11 -inches between the bars. Upon these bars was fixed 6 inches of hard wood -planking (see fig. 15, _a_), and on this again came the framing of the -cradles. Tapered timbers (_b_) were driven in, so as to fill up the -wedge-shaped space between the hard wood over the bars and the flat -bottom of the ship. On the side next the river, between these timbers -and the rounded part of the under side of the ship, were driven in -separate wedge-shaped pieces (_c_), which were secured to the timbers -below by long bolts, arranged so as to allow the removal of the -wedge-pieces when required. The means of unbolting the wedge-pieces was -an essential provision for floating off the ship, as they had to be -removed before she could move sideways off the cradles. Resting on the -lower timbers of the cradle were stout props (_d_), which pressed -against the ship's side higher up than the wedge-pieces, and took part -of the weight, and spread it over the outer part of the cradle. There -were similar props (_e_) on the landward side of the cradles. - -[Illustration: Fig. 15. Transverse Section of Ship, showing Ways and -Cradles. - -_Scale of feet._] - -There were 80 rails on each of the ways, and nearly 60 transverse bars -under each cradle; so that there were 9,000 intersections of the bars -and rails. As the ship and the cradles weighed 12,000 tons, each -intersection carried on the average a weight of 1-1/3 tons. - - * * * * * - -After the construction of the ways was settled, the amount of power -required to move the ship down had to be determined. - -The motive power was not simply the chains, tackle, presses, &c.; but -there was also the action of gravity. One motive power, then, was not -only available, but was inevitably present; and, as the ways were at an -inclination of 1 in 12, the motive power of gravity upon the weight of -12,000 tons was 1,000 tons. The question to be decided was, whether the -1,000 tons of motive force was sufficient to overcome the friction; and, -if not, then what additional force would be required to do so. - - * * * * * - -In January 1857, immediately upon the adoption of iron sliding-surfaces, -an experiment was arranged on a considerable scale, in order to form -some idea on this important point. Two rails were laid at an inclination -of 1 in 12, and upon them an experimental cradle was placed, weighing -some 8 tons, and representing a small portion of the actual cradle. - -The effect of the friction of iron sliding-surfaces may be summed up -very simply. It appeared that the motive power need not, at most, be -more than would have been given by placing the ways at an inclination of -1 in 8, and that restraining power could not have been safely dispensed -with if the ways had been placed at a greater inclination than 1 in 16; -as it was observed that, contrary to received notions, the friction -became less as the velocity increased, and that, in case any -considerable velocity were attained, a great force would be required -merely to overcome the motive power of gravity down the incline, -independently of that required to destroy the velocity.[159] - -The task of getting the ship from the place where she was built to her -moorings in the river divided itself naturally into two parts--the -moving of the ship down the ways, and the floating her from off her -cradles. - -This subdivision of the whole undertaking of the launch into two almost -distinct operations is of great importance in considering the manner in -which Mr. Brunel conducted them; especially when it is borne in mind -that one, the moving down the ways, was capable of being, by careful -precautions, rendered almost safe; whereas the other, the floating the -ship off, was dependent on the successful issue of various minor -operations, in the management of which the fallible human element had a -greater share, and where small accidents, though, in their primary -effects, productive only of delay, might cause irretrievable disaster. - - * * * * * - -In the operation of lowering the ship, there had to be provided both -power to move her and power to check her motion. In floating, but one -force was necessary, namely, that required to pull the ship off if she -got jammed on the cradles. - - * * * * * - -With a desire to provide for the possibility of an extreme amount of -resistance on the ways, Mr. Brunel designed a complete hydraulic -apparatus, which would have been sufficiently powerful to move the ship -down without interruption or delay. It is much to be regretted that he -did not persist in carrying out his original intention. - -In the operation of floating, chains and tackle were the best means of -supplying the tractive force that might be required; and Mr. Brunel -decided to have a very large amount of available power. If the weather -were fine, and the tide at its calculated height, if no part of the -cradles got disarranged, if the calculations as to the ship's draught of -water were correct--if everything went right, there would be no -necessity for any great hauling power; a few tug-boats would suffice to -take the ship to her moorings. But Mr. Brunel determined that in this -critical operation of floating he would not trust to good fortune, when -the absence of it might produce grave injury. The power which he thought -it desirable to provide in chain purchases for the floating was very -considerable, being equal to a pull of 500 tons. - -As it seemed probable that the ship would not require much force to move -her down the ways, it seemed also probable that the river tackle (as the -chains and appliances for hauling the ship off were called) would be -sufficient for both purposes. This being the case, it at the time -appeared right, in the embarrassed state of the Company's finances, to -dispense with the more powerful and costly apparatus which Mr. Brunel -had proposed for moving the ship down; there being no fatal consequences -to be apprehended from a defect of power. - -Influenced by these considerations, Mr. Brunel resolved to trust to the -river tackle alone. - -He referred to this decision in a letter to the Secretary of the Company -written during the launch:-- - - - November 26, 1857. - - My original intention, the right one, was to fit up properly such - an hydraulic apparatus as should be fitted to move the ship the - whole length of the ways, and to depend upon the whole river tackle - only in the event of her moving very easily, and for getting her - off the ways at the end. From an unwise attempt to economise I - determined to dispense with the immediate costly apparatus for - pushing, and by sufficient power merely to move the ship at - starting or in the event of sticking,[160] and to depend upon the - same river tackle to keep her moving down the ways. - -The experiments made with the trial cradle had shown the necessity of -providing a certain amount of restraining force. As will be seen in the -description of the launch, it was only used once, but it must not -therefore be supposed that there was no necessity for providing it.[161] - -The arrangement of the checking gear was the same at each of the ways. -Attached to the land side of the cradle, by means of bolts, was a strong -iron framework which held two large horizontal wheels or sheaves. At the -upper end of the ways another sheave was fixed in a strong timber -framing; and opposite the middle of the upper end of the ways was placed -a large windlass or drum. - -This drum was a cylinder, about 20 feet long and 6-1/2 feet in diameter, of -solid timbers, strongly bolted together, and secured at each end in a -broad cast-iron disc, 12 feet in diameter. - -To a point in the framing was attached one end of a 2-5/8-inch chain -cable; this chain was passed round one of the sheaves attached to the -cradle, then round the sheave attached to the upper end of the ways, -then round the second sheave attached to the cradle; and its end was -coiled round the drum. Thus, as one end of the chain was secured, it was -necessary, before the ship could move down the ways, that the drum -should revolve, and slacken the end of the chain coiled round it. - -Round the discs of the drum were wrought-iron straps; these, when -tightened by levers, formed brakes by which the revolution of the drum -could be retarded. Gearing was provided with a train of toothed wheels, -so that the drum could be turned round by handles, and the chain wound -on to it. - -The following paragraph is from the commencement of a memorandum by Mr. -Brunel on the launching arrangements, written about five weeks before -the launch began:-- - - - September 26, 1857. - - It is expected that, with the present construction of the ways, the - friction and the tendency to descend by gravity will be about - balanced; so that when once in motion no very great amount of power - (at least, in proportion to the mass to be moved) will be required - to keep the vessel in motion, or to check it if disposed to move - too quick, or quicker at one end than at the other; still the - forces which may be required either to help it on or to check it, - though relatively small as compared with the mass to be operated - upon, will be very large as compared with forces usually obtained - by the ordinary means of rope or chain purchases, and at the first - start, or after any accidental or intentional stoppage, a still - larger power may be required. - -The apparatus which Mr. Brunel prepared for performing the double duty -of moving the ship down the ways and hauling her off the cradles was as -follows:--At each end of the ship was a powerful chain tackle. One end -of a chain cable was secured to a mooring in the river, and it was -passed round a large sheave attached to the ship, then round a sheave -fixed on a barge about 300 feet from the ship, and the end brought on -shore, where it was hauled on by a chain tackle worked by a steam crab. -The sheave attached to the ship at the bow was slung by chains about 80 -feet from the stem. The sheave at the stern was fixed on the end of the -screw shaft. These purchases were intended to be good for 80 and 100 -tons respectively, and were to be able to follow up the ship quickly if -she moved. - -In addition to these purchases, Mr. Brunel desired to have 'the means of -bringing a considerable strain to bear in the event of the ship sticking -at starting, or at any subsequent time, and particularly at the last;' -and he considered that 'nothing under 250 or 300 tons would be of any -use for the purpose.' This power he desired to apply to the centre of -the ship between the two cradles by means of double crabs and treble -purchase blocks on four barges. - -One of the double crabs was mounted on each of the four centre barges, -and was placed on a platform, elevated so that the blocks of the chain -tackle could pass underneath it. This tackle was made fast to a chain -attached to the ship; and the mooring chain extending across the river -was hauled on by the tackle. - -Each of these four crabs and tackle was to be capable of working up to a -strain of 80 tons. The strain which Mr. Brunel intended to be able to -put on the ship by the river tackle, in the form of a good continuous -pull, was in all 500 tons. - -Two hydraulic presses were also provided, one at each of the cradles, to -overcome adhesion in first moving the ship. Each of these presses should -have been able to exert a strain of 300 tons. Therefore, including the -force of gravitation, the power which Mr. Brunel hoped to have to start -the ship was 2,100 tons, or more than one-sixth of the weight to be -moved; and for a continuous steady pull to keep her moving, 1,500 tons, -or one-eighth of the weight. - - * * * * * - -It was at one time thought possible that the launch might be effected in -October. But it was found that it would be impossible to be ready before -the spring-tides at the beginning of November; and even then, when the -time came, there was considerable hurry, and important matters were, as -will be seen, insufficiently attended to. - -The cradles were put together and wedged up under the ship, and every -effort was made at low water to extend the ways as far as possible; so -that, by moving her further down the slope, a greater margin might be -obtained, to allow for any falling off in the expected level of the -tide, or for any miscalculation in the ship's draught. - -In the memorandum already referred to on the launching arrangements Mr. -Brunel instructed Captain Harrison to superintend the moorings for the -river tackle, and to satisfy himself of their sufficiency. A few days -afterwards he wrote to Captain Harrison on the subject:-- - - - September 30, 1857. - - I fancy (I may be wrong) that you hardly estimate sufficiently - highly the forces that we may require to get the ship down if she - sticks at all, or to drag the cradle from under her, or to force - her off the cradle at the last. She _may_ move down pretty easily, - and the cradles _may_ possibly not stick; but if she does stick at - all, it is as likely to require a dead pull of 500 tons as not, and - we must not shut our eyes to the real exact amount of strain which - may and will come upon purchases and moorings, &c., if this force - is required and is exerted; but we must provide for it. The several - moorings must really be good for the 80 and 100 tons respectively - mentioned in the memorandum--and we must not rest satisfied with - the feeling that the moorings are stronger than any generally sold - or than common tackle will effect, but must apply purchases that - will produce the strain, and if necessary we must strain them to - it; and our moorings ought to be beyond a doubt. - - We are going to move 11,000 tons, a far greater weight than ever - was moved before, and we must not hesitate at providing a clear - pull of 500 tons; but bear in mind that 500 tons clear pull is - something much beyond what one is accustomed to. The power usually - brought to bear with purchases, chain cables, &c., is never - measured, but is very small; and we must take care and not be - misled by comparison with them. 80 tons is a heavy pull, and - nothing under 2 or 2-1/4 chain will be safe.... - - These are great strains we have to deal with, but they must be had, - and therefore we must meet them boldly. - -Frequent enquiries were now made relative to the time of launching; and -the number of applications which poured in for admission to the yard led -Mr. Brunel to write the following letter to the Directors of the -Company, and it was published by them in the newspapers. In it he not -only removed current misapprehensions as to the nature of the proposed -operations, but he also took the opportunity of pointing out that there -would be no risk to the ship in the mode of launching adopted, and that, -although it might at first be unsuccessful, further power could be -applied, and the ship safely launched. - - - October 23, 1857. - - The difficulty of replying to the numerous enquiries made - respecting the period at which the ship will be launched seems to - render it desirable that some means should be taken of giving the - information generally, that it may be uncertain, up to the end of - next week, whether the ship will be launched on the 3rd proximo or - the 2nd of December, and also of correcting the erroneous - impressions which exist as to the nature of the operation, which - can only lead to the disappointment of those who are erroneously - anticipating a display, on an unusually large scale, of that which - is a beautiful spectacle with ships of ordinary dimensions. - - As regards the period of the launch I have, for some time past, - calculated upon being ready by the first tides of next month, and - by the unwearied exertions of those on whose assistance I have - depended, with the advantage of unusually fine weather, the - principal works required are so far advanced that there seems every - prospect of success; but a change in the weather is threatening, - the time remaining is short, and comparatively small causes may - create such delay as to render it more prudent, if not unavoidable, - to postpone the operation until the following available tide, - namely, that of December 2. As no mere desire to launch on the day - supposed to have been fixed will induce me to hurry an operation of - such importance, or to omit the precaution of a careful and - deliberate examination of all the parts of the arrangements after - all the principal works of preparation shall have been completed, - should such postponement prove necessary or be adopted from - prudence, everything having been now prepared, the launch would be - on December 2. - - As regards the nature of the operation, it has frequently been - stated, but it seems necessary to repeat it, that the ship will not - be 'launched,' in the ordinary sense of the term, but merely - lowered or drawn down to low-water mark, to be thence floated off - by a slow and laborious operation, requiring two and possibly three - tides, and very probably effected partly in the night, and at no - one time offering any particularly interesting spectacle, or even - the excitement of risk; as I am happy to feel that, even assuming - accidents to occur or miscalculations to have been made, rendering - the operation unsuccessful--the ship may stop halfway or not move - at all, more power or other remedies may have to be applied--but no - injury to the ship can result from any failure in the course of - proceeding in this mode of launching. - -Throughout October an immense amount of work had to be done, and the -multiplicity of matters to be attended to pressed heavily on Mr. Brunel -and his assistants. - -With the check tackle he had reason to be content. The chains, which -were the ship's cables, had been very carefully made; and, in addition -to the usual tests, pieces had been taken at hazard, and were found to -bear a good breaking-strain. - -The river tackle was not so satisfactory. In operations that have to be -conducted afloat unexpected delays arise, and all the work may be -suspended by bad weather, and it is moreover frequently dependent on -tides. In the present case the work to be done was not easy. Heavy chain -cables had to be laid out, and moorings picked up and connected to the -tackles; one work having often to wait for the completion of another. - -Mr. Brunel had determined that each purchase should be tested by being -strained to the utmost stress for which it was intended; but, owing to -the delays which had occurred in preparing the river tackle, this was -not done. - - * * * * * - -A few days before the launch Mr. Brunel addressed the following -memorandum to all who were to take part in the operation:-- - -_General Arrangements and intended Mode of Proceeding._ - - - October 30, 1857. - - It is desirable that all engaged in directing any part of the work - should understand the general course of proceeding which it is - intended to pursue, so far as may be found practicable; - circumstances may modify these pre-arranged plans, and may compel a - total departure from them, but every endeavour will be made to - adhere to them. - - - GENERAL COURSE OF PROCEEDING. - - [Sidenote: To start about noon of Tuesday.] - - I propose to commence operations about two hours before high water, - or about noon, and to endeavour to get the ship down as quickly as - I can into the water, and down to within about 36 feet of the - bottom of the ways. - - My object in starting at this particular time of tide would be to - get the ship into the water, and waterborne to some extent as soon - as I could. - - [Sidenote: Stop short of end of ways.] - - I propose to stop short of the end, in order to avoid the necessity - of having to knock away all the shores, and clear the cradle at the - evening tide, when it would be dark, and to float on the morning - tide, when it would be also dark. - - I should propose then to stop about 36 feet short of the end.[162] - - [Sidenote: _Evening._ Clear away shores of the 20-feet cradles.] - - At low water, although dark, I shall endeavour to knock away the - shores of the 20-feet cradles, or as many of them as possible, and - clear all from these cradles except the unbolting of the - filling-pieces. - - [Sidenote: Under favourable circumstances clear away also _all_ the - shores on the port side.] - - If the operations have proceeded easily, and the ways not sunk - much, I shall also knock away all the long shores on the inshore or - port side of the ship, so as to leave less to do on the following - day. - - [Sidenote: Prepare for a further pull at the night's high water.] - - I shall then prepare at leisure to place the barges to get one pull - of 36 feet, or as much more as I can (as I shall not hesitate to - pull the cradles 20 feet off the ways) after high water of that - night. - - [Sidenote: Last move at 4 A.M.] - - Soon after the high water of that night, and when the water has - fallen sufficiently to prevent any risk of floating, but while the - ship is still waterborne, probably about 4 or half-past 4 A.M., I - shall make the last pull; and although it will be in the dark, yet - having only one pull to make, and plenty of time to prepare, and no - expedition required in the operation, I think it may be easily - done. - - [Sidenote: Float on high water, Wednesday afternoon.] - - The ship will then be left till low water, when we shall clear away - everything we can from the cradles, and get all ready for floating - at high water on the afternoon of Wednesday. - - Provided the mechanical arrangements should prove efficient, the - success of the operation will depend entirely upon the perfect - regularity and absence of all haste or confusion in each stage of - the proceeding and in every department, and to attain this nothing - is more essential than _perfect silence_. I would earnestly - request, therefore, that the most positive orders be given to the - men not to speak a word, and that every endeavour should be made to - prevent a sound being heard, except the simple orders quietly and - deliberately given by those few who will direct. - -In a memorandum of 'Particular Instructions,' dated the next day, -October 31, there is the following passage:-- - - _Starting_.--A strain being brought upon all the purchases, and the - holding-back purchase being slack, if the ship does not move, the - two presses will then be worked; if she does not then move, or if, - when moved, she stops and each time requires the presses, the - attempt will be postponed, and more moving power applied for the - next time. - - If, after being started by the presses, the river purchases are - found sufficient to move her, the operations will proceed. - -In another part of these 'Instructions' Mr. Brunel again shows that he -was not, as has sometimes been supposed, under the impression that the -friction would be so small that the only important thing to be thought -of was to check the ship from rushing too fast. - -On the contrary, he foresaw the possibility of her not moving at all, -even with the presses, that is to say, with a force of 1,100 tons over -and above the action of gravity. If after moving she stopped, and then -required the presses again to move her, this would show that the -operation could not be properly carried out, and that the work must be -suspended till more motive power was applied. If, again, the river -tackle were sufficient to move her, then the work was to proceed, but -the friction might even then be so great as to render it desirable to -remove all retarding force. He says, in another passage in his -'Instructions:'-- - - It is very likely that no checking whatever at the drums will be - found necessary, but that, on the contrary, it will be found - desirable to get rid of any resistance by overhauling the heavy - chains through the sheaves. - -The best day on which to begin the launch was Tuesday, November 3, as it -left two or three days of the high full moon spring-tides for the -operations, should they be prolonged. - -On Monday, November 2, the chief work remaining to be done was stowing -kentledge or iron ballast on the cradles, to prevent the timbers -floating when the ship should be moved off them. All the appliances were -ready, and, except the river tackle, had been carefully examined. This, -as has been already said, had not been tested. - -It was now for Mr. Brunel to consider whether, in consequence of the -river tackle not having been properly tested, he should postpone the -launch till the following month. - -It was most important for the Company that the ship should be afloat as -soon as possible; and, as any defects which might exist in the river -tackle would almost certainly declare themselves in the earlier part of -the operation, when nothing worse than delay could be apprehended, Mr. -Brunel, after a careful review of all the circumstances, determined to -attempt the launch. - - * * * * * - -On the morning of November 3, the work of putting kentledge on to the -cradles was completed by firelight, and the rails were rubbed over with -a mixture of oil and black-lead. All the shores and props which -supported the weight of the ship had been removed, and she was now -resting entirely on the cradles. - -Later on in the morning the brakes of the drums were tightened down, and -the dogshores were removed from the ways in front of the cradles. Mr. -Brunel, who had been engaged from an early hour in examining all the -preparations, superintended this operation, and, having satisfied -himself that all was clear and ready, returned to the upper part of the -yard. - -By this time it was crowded with people. The Directors, contrary to Mr. -Brunel's expressed wish, and without informing him of their intention, -had issued a large number of tickets of admission. A few days before, -Mr. Brunel had suggested that four policemen should be obtained, -thinking that all they would have to do would be to contend with -trespassers. The police force actually present were ignorant of the -portions of the yard to be kept clear, and Mr. Brunel had himself to go -and assist in ordering visitors away from the neighbourhood of the path -prepared for the tackle of the stern hauling gear. The crowd soon became -so great that it was almost impossible for the men in charge of the -hauling-engine at the stern to see the signals given from the middle of -the yard, or for those in the middle of the yard to see what was -happening at the stern. - -At about half-past 12 o'clock the fastenings of the ship at the bow and -stern were let go, and Mr. Brunel ordered a small amount of slack to be -given off from each drum. This was done by men turning the handles of -the gearing which had been provided for winding the chain on to the -drums. The order was then given to haul on the bow and stern tackle, and -to pump at the hydraulic presses. It is doubtful what amount of strain -was put on by the tackle and the presses, but it was probably not very -great. - -Presently a shout from the forward cradle announced that it was moving, -and almost immediately the stern cradle also started with what appeared -to be a considerable speed. The men who had been engaged in turning the -handles of the gearing had remained leaning against them. As soon as the -ship had moved a few inches, she took up all the slack chain. This made -the drum revolve, and the handles of the gearing spun round very -rapidly, striking the men, and throwing them into the air. The men who -were at the brake-handle next to the gearing ran away. Mr. Brunel, who -was standing near the drum when the accident happened, shouted to the -men to hold on to the brakes, and ran to the spot. The men who had -remained at the other brake-handle hauled it down with the tackle. A -great restraining force was thereby brought upon the ship, and her -progress ceased; the forward cradle having moved 3 feet, and the after -cradle 4 feet 3 inches. - -Five men were injured. On the death of one of them it was stated at the -inquest, by the foreman of the drum, that, after the slack had been paid -out, he had ordered the men to stand clear. Be this as it may, it cannot -be denied that the handles should not have been used after the securing -chains had been let go; and indeed Mr. Brunel said at the inquest, 'I -may blame myself, for I did not anticipate that the handles would have -revolved so rapidly.' - -After this accident, Mr. Brunel determined to wait till high water -before recommencing the operations. In the meantime the gearing was -removed from both drums. - -A more important change was also made in the arrangements. When the ship -moved, the men on the four middle barges became frightened, thinking she -was about to overwhelm them; a rush was made, and one man, jumping into -a small boat, shoved off, leaving the rest to their fate. A report was -at once sent to Mr. Brunel that the men were untrustworthy, and that -they would not remain; and that, as the barges would be of no use -without the men, the chains had better be dropped and the barges -removed. To this Mr. Brunel consented. - -It would, however, have been sufficient to take the men off, leaving a -tug-boat and a few steady men to keep the barges out of the way of the -ship; they would then have been available if required. Mr. Brunel, a -short time after he had given the order, ran round the bow with Captain -Harrison to countermand it; but it was too late, as it had been already -acted upon. As events turned out no harm was done, as the centre barges -alone would not have been sufficient to go on with, after the rest of -the tackle failed. - -The result of these changes was that when the operations were -recommenced, the only hauling gear was the bow and stern purchases; the -hydraulic presses were also available to start the ship. - -At a little after 2 o'clock the signal was given to haul on the bow and -stern tackle, the presses being at the same time pumped up. The brakes -of the drums were slackened, but kept all ready for tightening. - -Not long after the strain had been brought on the tackle, several of the -teeth of one of the wheels of the bow steam crab gave way, and the chief -anchor at the stern began to drag, so that no efficient strain could be -obtained. On this being reported, the operations were discontinued; and, -as there was no possibility of getting things ready by the next day, the -launching operations were postponed till December 2, the next full moon -spring-tides. - - * * * * * - -As soon as this was known the visitors rushed in on the works, crowding -about the cradles and ways; and Mr. Brunel had to postpone those -investigations which he wished to make at once.[163] The whole yard was -thrown into confusion by a struggling mob, and there was nothing to be -done but to see that the ship was properly secured, and to wait till the -following morning.[164] - - * * * * * - -The next day was devoted to an examination of what had gone wrong, and -to the consideration of what should be altered before another attempt -was made. - -At the stern mooring the anchor was bedded into the ground on the -further side of the river. - -The difficulty with regard to the four centre barges was got over by -placing the four crabs with their tackles in the yard, on the landward -side of the ship. The four chains attached to the ship, which had before -been hauled on directly from the barges, were now passed round sheaves -on the barges, and brought back under the ship's bottom to the tackles -in the yard. - -The chief alteration, however, was in the arrangement of the hydraulic -presses. On November 3, there were, as has been said, two presses. Two -additional presses were now provided; each of these consisted of two -7-inch cylinders, and was equivalent to a 10-inch press. - -With the object of being able to employ the presses continuously during -the descent of the ship, they were arranged to point down the ways at an -inclination of 1 in 12. The four presses were placed one on either side -of the check tackle at the two ways, and were supported by abutments of -timber-work. These abutments each consisted of four rows of piles, one -behind the other at intervals of about 8 feet. The press abutted against -the row of piles nearest to the ship, which were connected by wooden -struts to the piles behind them. Long balks of timber of various lengths -were prepared to transmit the pressure to the cradles.[165] - -The four presses might be considered equivalent, at their full power, to -a force of 800 tons; this was so much in excess of the small force that -had moved the ship on November 3, that, even making every allowance for -the advantage of the fresh lubrication in the first instance, it seemed -reasonable to suppose that with this force the ship could be moved down -easily. - - * * * * * - -As the process of moving the ship with the presses would naturally be a -slow one, Mr. Brunel determined to proceed with the operations as soon -as everything was ready. On November 19 the work was commenced.[166] The -bow tackle was hauled upon first, as the forward cradle was more than a -foot behind the after one, and the men at the forward presses were set -to work. After a short time the timber backing of the presses began to -crack and 'cry out'; and, without much stress on them, the abutments -were forced back some 3 or 4 inches. The mooring chain of the bow -tackle also gave way, although there was not any excessive strain on it. -On examining the abutments, Mr. Brunel saw the cause of their failure, -and ordered the strain to be taken off. The number of piles was -sufficient, but the way in which the strain was communicated to them did -not enable them to exert the proper amount of resisting power. - -This defect was cured by tying the heads of the rearward piles with -bolts to the foremost piles. The ship being secured, each press was -tested to a full strain, and the adequacy of its abutments ascertained. - -It was different, however, with the river tackle. The chain which had -parted was an old river mooring-chain of great size. Much delay in -replacing it was caused by dense fogs, which made it almost impossible -to work on the river. Moreover, there seemed a fatality about every -attempt to get a regular trial of any part of the tackle. When, at last, -a trial took place, and a strain was put on, a mooring-chain gave way; -then this had to be fished up from the bottom of the river, and pieced -together, the accident being ascribed to a defective link in the chain. -The trials were, therefore, so few that it was only proved by degrees -that all the regular moorings were worthless; although they had large -chains which ought to have been good for three times the strain put on -them. - - * * * * * - -The stubbornness of the ship on November 19 gave Mr. Brunel great -anxiety; not from any fear of being unable to apply sufficient power to -move her, but because, on continued consideration of the subject, he -apprehended that a serious difficulty might arise, if there should be a -prolonged delay at a particular part of the ship's progress. - -It has been explained that Mr. Brunel, with a view of obtaining -uniformity of bearing over the surface of the ways, had not attempted to -support them rigidly on piles, but had rested them on the river-bank. -As, however, the foundation of the building slip was comparatively -rigid, he feared lest an unequal subsidence might cause injury to the -ship, if she were stopped for any length of time before she had -completely left the ground on which she was built. He thought that if -the ways sank at this point they would assume a slightly convex form, -and tend to force upwards the flat bottom of the ship. The main part of -the ship's bottom, between the longitudinal bulkheads, could bend in -slightly under a heavy upward pressure; but this action could not take -place at the transverse bulkheads, as they would not yield without -injury. Mr. Brunel shrank from proceeding with the launch without having -in reserve such an amplitude of power as would prevent the ship's being -stopped at this critical point. This consideration, together with the -continued failure of the river tackle under such tests as were applied -to it, led him to address the following communication to the -Directors:-- - - - November 26, 1857. - - We proved two of the presses yesterday afternoon up to the full - pressure. A third, the largest, was proved partially; it required - some additions, which are nearly completed, and will be in a few - hours. The fourth may, I think, also be relied on to the same - extent, nevertheless, after a careful examination of the effects of - these strains and other circumstances, I have, after a night's - consideration, come to the conclusion that our means are too - imperfect to justify my moving the ship with them in their present - form. The presses would start the ship, but it is evident that if - required to be used constantly, that is repeatedly, the piles would - become loosened so as to draw and rise; this again might be - remedied by loading, but clumsily, and with other contingencies, - which I will report, combine to render it hazardous to depend upon - them. My original intention, the right one, was to fit up properly - such an hydraulic apparatus as should be fitted to move the ship - the whole length of the ways, and to depend upon the whole river - tackle only in the event of her moving very easily and for getting - her off the ways at the end. From an unwise attempt to economise I - determined to dispense with the immediate costly apparatus for - pushing, and by sufficient power merely to move the ship at - starting or in the event of sticking, and to depend upon the same - river tackle to keep her moving down the ways. The power originally - calculated upon for the river tackle has gradually, step by step, - failed us; the moorings supposed to be sufficient for certain - strains have failed us at one-third of those strains, another has - parted since our last attempt, and, instead of full 350 tons of - power from this source, we cannot now depend upon 200, and this, - added to the inefficiency of the pushing power, would risk the - sticking of the ship, which might occur exactly at a point which - would involve serious difficulty to remedy. I am assuming a - combination of adverse circumstances, perhaps not likely to occur, - but quite possible; and the conclusion I am compelled to come to is - that our apparatus is too defective, and that the original plan of - a proper and sufficient hydraulic apparatus, arranged in a complete - well-constructed mechanical manner, to push the ship continuously - down the ways, ought to have been followed out, and is now the only - mode of doing the work safely, that is, without the risk of being - involved in a difficulty much greater and more costly. - - I have only to add that bad as this report of our condition is, it - is at any rate the worst that can be made of it, that nothing - whatever has occurred to show that any new difficulty has arisen or - anything whatever to create any new difficulty. We could move the - ship now if it were wise to do so, but with great doubts whether - our pushing apparatus in its present form, imperfect and - unmechanical, would continue effective if repeatedly used, and the - certainty that our river tackle is far inferior to what is - required, and also of doubtful and more than doubtful permanency - for repeated strains, it would not be right to commence.... - -Mr. Brunel at the same time determined to obtain, on a large scale, a -measure of the deflection that might be expected from the weight of the -ship coming on the ways. More than 100 tons of kentledge was piled on a -portion of the ways 10 feet square, in such a manner as to give a -pressure thereon of about double that which would be produced by the -weight of the ship. - -It was necessary that this test should not be tried on too small a -scale, as a weight resting on an isolated patch would receive support -from the surrounding ground, which it could not of course do if that -ground was equally loaded. The ways sunk so little under the test as -completely to reassure Mr. Brunel, and to show that no serious evil need -be contemplated in the passage of the ship from off the place where she -was built on to the newly made ways, even though she might be again -stopped for some time. He therefore determined to go on at once with the -launching operations. - -The result of the test was very satisfactory to him, and it enabled him -to carry on the work with the same confidence as he had at the first -felt--'that the ship may stop halfway or not move at all ... but no -injury to the ship can result from any failure in the course of -proceeding in this mode of launching.' - -Shortly before the second attempt to move the ship, on November 19, the -experimental cradle had been again put up with a view of obtaining some -additional data as to the hauling strain that might be required. The -deductions made from them were the same as those obtained in the -commencement of the year, and encouraged the hope that the motive power -required would not be excessive.[167] - - * * * * * - -By Saturday, November 28, the four presses had been got ready; and the -river tackle, though still far from being beyond reproach, had been got -into place, and partly tested. - -The brakes were eased, and a small amount of slack was overhauled on -the check-tackle chains by the men stationed on the ways for that -purpose. As on the previous occasion, the pressure was to be first put -on the presses at the foremost cradle. - -Arrangements were made for promptly following up the ship if she moved -freely. A black board was placed on each cradle for recording the -progress of the ship. - -Mr. Brunel stood on a low platform in the centre of the yard, as a -convenient position from which to watch and command the operations. A -little before ten he gave the order to commence pumping, and the men at -the hydraulic presses got to work. When the pressure came on the timber -framing which formed the abutments, there was considerable noise of -creaking and crushing as the several parts subjected to strain came in -to their proper bearing. The men soon changed from the large plunger -handle to the small one which put on the full pressure; the timbers of -the abutments kept on crying out, but it was evident that they were not -yielding as they had done before. Presently, while the noise of the -timber-work was still attracting attention, the man in charge of the -measuring apparatus recorded on his black board a movement of one inch; -the ship was again in motion. - -She moved steadily, but slowly, under the force of the presses, at a -rate of about one inch a minute, and as soon as the forward cradle had -been moved about a foot in this way, the presses at the after-ways were -set to work, and the river tackle was put into operation, first the bow -and stern tackle, and then the four middle purchases. All went well with -the presses, but the strain had not been put on long, when the stern -mooring-chain and one of the two chains at the bow broke; an anchor at -the bow had also begun to drag. - -Later in the day part of the moorings of the centre barges also gave -way. Captain Harrison set to work to repair these defects as fast as -they occurred; in no way dismayed that, as he was at work remedying one -mishap, the news of another was brought to him. Barges had to be got -into place, the broken ends of cables fished up or under-run and pieced -together, and this often in the dark; for it must be remembered that the -work was going on at the end of November, when the sun rose, invisible -for fog, at half-past seven, and set at half-past four. - -With the exception of the river tackle, all had gone well; the presses -and their abutments had acted efficiently, and the ship had been moved -easily down the ways about 14 feet before work was suspended at night. - - * * * * * - -Though the progress had not been great, there still seemed a reasonable -hope that, by pushing on, the ship might be got down to the bottom of -the ways in time for floating her off at the next spring-tides, namely, -on December 2. Mr. Brunel therefore decided to go on with the operation -on the Sunday. Early in the morning the presses and crabs were again set -to work. The river tackle soon gave way; and, indeed, there was no -reason why it should be superior to that used the day before, as almost -all that could be done in the night was to piece together the broken -chains, and to replace the anchors. The moorings at the bow and stern -began at once to drag, and two of the mooring-chains amidships parted. -The hydraulic presses were then the only available power; and, although -the full pressure was put on, the ship did not move. This was very -disheartening; it was, however, thought that the resistance was due to -some exceptional adhesion. Every effort was therefore made to get -together the means of giving the ship a first start. - -It was not till the afternoon that a large number of screw-jacks and -hydraulic jacks which had been procured were got into place; they were -then screwed up hard, and the hydraulic presses being set to work, the -ship began to move in a manner very similar to that of the day before. -There was not, however, much daylight left; and, when night came on, the -distance traversed was only about 8 feet. The comparative facility with -which the ship moved when once started gave hopes that good progress -might be made the next day. - - * * * * * - -On Monday morning the ship moved without more difficulty than when she -had stopped the evening before, and the work went on quite -satisfactorily. She continued to move slowly, and by dinner-time had -gone about 8-1/2 feet. Three feet an hour was not much, but still if it -could be kept up it would suffice to get the ship down by the next -spring-tides. Arrangements were therefore commenced for lighting up the -ways and pumping machinery, so that the work might be continued through -the night. The repairs of the river tackle were pushed on, the ship's -anchors, which had just been finished and tested, were laid down for -part of the moorings, and some of the chains were replaced with chains -lent by the Government and by Messrs. Brown and Lenox. - -When work was recommenced after dinner the ship made a short slip of -about 7 inches. On pressure being again applied the 10-inch press at the -forward cradle burst. This put an end to all work for the day, and it -was then determined to replace the broken press and to add two more -presses to each cradle, before proceeding with the launch. - - * * * * * - -The preparations for the new presses were pushed on vigorously, but it -was not till the afternoon of Thursday, December 3, that things were -again ready for a start. - -The pumps were set to work and the tackle hauled upon. The ship made -several short slips of a foot or so, and then moved more than 5 feet at -one slide. When darkness set in she had moved about 14 feet, in slips of -greater or less length.[168] - -On Friday, December 4, all was ready early, and during the morning -everything went as well as on the day before; but in the afternoon -increased difficulty was found in getting the ship to move, and the -14-inch press at the after cradle burst, as did also a 7-inch cylinder -of one of the coupled presses. - -Notwithstanding the delay due to the bursting of the presses, the ship -was moved some 30 feet; but there was no longer any chance of getting -her afloat at the spring-tides, and the increased adhesion gave cause -for the fear that still more power would have to be applied. - - * * * * * - -On the next day, Saturday, December 5, the ship made a short slip; but, -although the pressure was kept constantly on, no further advance was -made until late in the afternoon. Mr. Brunel then tried suddenly letting -go the strain on the stern tackle. The sudden relief of the side-way -strain on the end of the ship sent a tremor through the hull, which -served to destroy the adhesion, and she slid several inches. This -operation was several times repeated, and although there were a number -of vexatious delays from pushing-pieces giving way and other mishaps, -she was moved by the evening a distance of about 7 feet, the resistance -due to adhesion being very great. - - * * * * * - -On Sunday some of the presses farthest from the cradles were moved down -the ways nearer to the ship, so as to avoid the necessity of using long -pushing-pieces, which required much attention to prevent their bulging -sideways. The river tackle now consisted of the bow and stern -steam-engine purchases, and two crabs and tackle, one at each end of the -ship. The moorings opposite the centre of the ship having proved -worthless, it was necessary to lay down new moorings, and it was found -more convenient to lay them opposite the ends of the ship. - - * * * * * - -The next day, Monday the 7th, after the commencement of operations, -considerable delay was caused by the failure of some of the feed pipes -of the presses. These defects were not cured till after dinner-time, -when the operations were resumed, and before dark the ship was moved -about 6 feet. - -On the following morning several short slips were made, and the ship had -been moved about 4-1/2 feet; but, at 10 o'clock, a dense fog came on, and -rendered it impossible to proceed. The next day was occupied in -re-arranging the tackle and presses. - - * * * * * - -These were not ready till the morning of Thursday, December 10; when, on -the presses being again set to work, and one of the chains being as -before suddenly slackened, the ship made one slip of a little over a -foot; but, on the strain being again applied, two of the anchors began -to drag. As it was now essential to have the river tackle, in order by -shaking the ship to destroy the adhesion, and by the drag of the -catenaries to increase the length of the slides, Mr. Brunel determined -to dispense with the anchors, and to attach the chain cables to piles -connected by framework. These abutments or pulling points for the chains -were now constructed on the other side of the river, opposite the bow -and stern of the ship. - - * * * * * - -The launching operations last described, namely, from December 3 to -December 10, were full of incident. Nor was the scene wanting in that -animation which agreeably interests a bystander, the more so if he is -not thoroughly conversant with the meaning of all he sees and hears, so -that he mistakes a loudly spoken word, loudly spoken merely that it may -be plainly heard, for a prompt and urgent command. - -The labourers at the pumps relieved the monotony of their work, and -shook off the cold, by taking a lively and talkative interest in the -progress of the launch, and echoed the orders given them to pump with -the 'big plunger,' or 'little plunger' of the pumps, or to 'fleet' the -press. This and the singing of the gangs, which were constantly at work -moving chains for the repair of the river tackle, or rolling logs of -timber on to the ways to serve as pushing-pieces for the presses, gave -plenty of life to the operations; and then when the pressure had been -got on the presses, and shouts from the bow and stern of the ship passed -the word that the river tackle was hauled taut, the order would be given -to 'let go' the chain at one end of the ship. Immediately the rattling -noise announced that this had been done, and, after a second or two of -anxious watching, the ship slid off, the timbers, abutments, and -pushing-pieces creaking and groaning as the strain was suddenly -relieved. While the ship was in motion, the whole of the ground forming -the yard would perceptibly shake, or rather sway, on the discharge of -the power stored up in the presses and their abutments. The appearance -of the ship moving sideways in these short slips, when seen from the -ways, was very imposing. - -All these somewhat striking surroundings of the operations were -naturally heightened in effect, when the work was being carried on in -the early morning or late in the afternoon; and when the timber-framing -and the groups of men at work were illuminated by the glare from the -open fires which were kept burning near the pumps and presses. - - * * * * * - -The preparations already described were not completed till December 15. -In the meantime Mr. Brunel had been joined by his friend Mr. Robert -Stephenson. Mr. Stephenson had not been aware of many vexatious -circumstances which had even prevented Mr. Brunel from making full use -of his own staff of assistants. Mr. Stephenson expressed to a common -friend his regret that Mr. Brunel had not invited him down to the ship, -and said that he should have gone down uninvited, but that he thought -Mr. Brunel had reasons for not wishing it. On the state of affairs being -explained to him, Mr. Stephenson said, 'I'll go down to him at once;' he -did so, and his arrival at Millwall was very welcome to Mr. Brunel.[169] - -Mr. Stephenson agreed with Mr. Brunel as to the expediency of -suspending operations until an ample excess of power was applied. -Fortified by the support of Mr. Stephenson, Mr. Brunel was prepared to -advise the Directors to adopt this course; but, as the preparations for -recommencing the work were just completed, it was determined to make a -trial on the afternoon of December 15. The presses were all pumped up, -and the river tackle hauled on; but, although the force applied was at -least 300 or 400 tons greater than that which had last moved her, the -ship did not yield, and the attempt was abandoned. After a careful -consultation on the depressing result of this day's work, it was -determined to make another attempt the next morning, in order to see if -any new form of difficulty had arisen; and that after this operations -should be suspended, and an ample number of additional presses provided. - - * * * * * - -The following day, December 16, as soon as Mr. Brunel and Mr. Stephenson -had arrived, the pressure was again put on the presses, and the river -tackle having been hauled taut, the chains at the bow were let go, and, -to the great satisfaction of all present, the ship made a short slide. -The record of her movement showed that, although the adhesion was much -greater, the retarding force of friction was about the same as before, -and that therefore there was no reason to assume the existence of any -special obstacle. Another short slip was made; but, in getting up the -pressure again, a press was burst, and the work was then stopped.[170] - -Mr. Brunel's decision to suspend the launching operations at this point -was approved at a meeting of the principal shareholders held the next -day. His report to the Directors, and a memorandum of a verbal statement -which he made to the meeting, are as follows:-- - - - December 17, 1857. - - In my letter of October 23, which was published at the time in the - daily papers, I referred to the possible contingency of the power - provided to move the vessel down the ways proving insufficient, and - the operation then about to be attempted being so far unsuccessful; - and, referring to what I considered a countervailing advantage in - the absence of risk, I stated, 'the ship may stop half-way, or may - not move at all, more power may have to be applied, but no injury - to the ship can result from any failure in the course of proceeding - in this mode of launching.' - - The result has been that after moving the vessel nearly half the - distance to low water, it has become necessary to increase very - considerably the power which has effected this much, although it - had already been much added to during the operation. - - This will unavoidably be attended with some expense and delay, but - not considerable, as the requisite hydraulic presses can be - obtained ready made, and their application is simple, and the - result cannot, I apprehend, be doubtful. - - I do not mean to imply that I contemplated any such great increase - of resistance as probable, such experiments as could be made before - moving the ship having given me good reason to hope for a different - result; but the possibility of it was contemplated, and I refer to - this merely as explaining the statement I now make, that the - difficulty is simply one of degree, of more or less power being - required, and that nothing whatever has occurred to create any new - class of difficulty. The launching ways, about which anxiety had - been expressed, and not unnaturally, have stood perfectly and - without any settlement or any derangement by being passed over. - There is no change of gradient or inclination in the ways capable - of producing any effect, as has been supposed; the upper part of - the ways having an inclination of 1.025 inches per foot, and the - lower part, where the ship now is, one of 1.000 per foot, a - difference too small to be appreciable, but which possibly by some - mistake of figures may have led to the erroneous impression - referred to. - - The amount of resistance upon the ways in their present condition - and inclination has now been positively ascertained, and an ample - excess of power being applied, there can be no reason to doubt the - result. I propose to apply that excess by going considerably beyond - the amount which the calculation founded upon the results actually - obtained would give as the maximum, and to double the power which - has last moved the vessel. - - -_Memorandum of a verbal Report made to the Directors, and a small -Meeting of the Principal Proprietors._ - - - December 17, 1857. - - That after full consideration of all the circumstances, and - assisted by the best advice I could call in to my aid, namely, that - of my friend Mr. Robert Stephenson, I considered that the only mode - of proceeding, and one which there appeared no reason to doubt - would succeed, was to apply considerably more press power; that I - proposed to double what we had; that I believed I was able to put - my hands upon the requisite presses; that the river tackle so far - as it went might now be considered good, but that unfortunately we - were obliged to take up the principal part of the chains, which - with great kindness and liberality Messrs. Brown and Lenox had lent - us, and were now peremptorily called upon to deliver up; but that - with their assistance I could replace them.... - -A large number of presses were obtained, the owners for the most part -lending them free of charge. Among these presses was the large one, with -a 20-inch cylinder, which had been used for lifting the tubes of the -Britannia Bridge. - -On each of the ways were placed nine presses. The total sectional area -of the cylinders at the forward cradle was 1,066 circular inches, and -that of the cylinders at the after cradle was 1,358 circular inches; -but the Britannia press was not to be worked to its full power, so the -total area of the cylinders may be taken as 2,300 circular inches, or -1,800 square inches. The presses might be considered as good for at -least 2-1/2 tons on the square inch; this gave a power of 4,500 tons, -which, with the 1,000 tons due to gravity, gave 5,500 tons, or equal to -nearly half the weight of the ship. The presses were now coupled -together in groups, in order to ensure that an equal pressure should be -brought on them; and to each of these groups an accurate pressure gauge -was attached. - - * * * * * - -All the presses having been tested, it was determined to recommence the -actual operation of launching on Tuesday, January 5. - -So much of the water in the pipes had been frozen that it was eleven -o'clock before the order was given to the men to pump. When at one group -after another the pressure was shown to be one ton on the circular inch, -the pumps were stopped. As the backing of the presses continued to yield -slightly, a stroke or two of the handles had to be made from time to -time, to keep up the required strain. For six minutes there was perfect -silence, and then the ship moved, sliding down about 3 inches. - -The same process was repeated at the stern cradle once or twice, and -then at both cradles. After this the order was given that the pumps -should be kept going till she moved. This was accordingly done, and when -the pressure amounted to 1-1/4 ton on the circular inch the ship made a -slide of about 4 inches. In this manner she was moved about 5 feet -before work was stopped in the evening.[171] - -On January 6, there was a singular change in the behaviour of the ship. -During the whole of the forenoon she moved gradually, yielding to the -pressure at a rate of about an inch in four minutes. In the afternoon, -however, she moved in short slides. - -During this and the three following days her progress was about 10 feet -each day. After this the ship, being to a considerable extent -waterborne, was moved with greater ease, and on Tuesday, January 12, 20 -feet was accomplished in less than four hours. - - * * * * * - -By Thursday, the 14th, the ship had traversed a distance of 197 feet at -the forward cradle, and 207 feet at the after cradle. It was thought -unwise to advance further till the coming spring-tides on the 19th of -the month were past, lest an exceptionally high tide might come -unexpectedly, and partially float her. As soon as the spring-tides had -passed, she was moved on cautiously, a short distance at a time, and the -depression of the ways was carefully observed. This was found to be -inconsiderable, and the cradles were gradually pushed 25 feet off the -ways. As the spring-tides came on, water was run into the ship, to -prevent her from floating prematurely. - - * * * * * - -The upright struts of the cradle on the side next to the river were all -removed, and the wedge-pieces had chains fastened to them, with the ends -brought on deck; so that, if any of the wedge-pieces got jammed and did -not come out when the ship floated, they might be hauled out by the -chains. - -The river tackle now consisted of two purchases at the bow and two at -the stern. To keep the ship, when she floated, from being drifted by -the tide or wind, chains were carried from the bow and stern to -moorings, by which her movement up and down stream might be regulated. -Four tugs were in attendance to tow the ship to her berth, and a -floating fire-engine was also ready to pump water into her, should this -be necessary owing to any sudden postponement of the launch. - -Nothing now remained but to watch carefully for a suitable tide. - - * * * * * - -It was determined that, if the weather were favourable, the floating -should be effected on Saturday, January 30. The tides had been below the -average, and on the Friday matters did not look promising; the tides had -continued low, and the weather was bad. A careful watch was kept on the -tide, observations being taken every half hour, and plotted on a diagram -so as to show at a glance the probable height to which it would rise. - -The tides showed signs of improvement, and they commenced to pump water -out of the ship on Friday night; but, as time went on, the weather did -not mend, and the wind was blowing from the south-west against her -broadside; therefore in the early morning Mr. Brunel, who was in person -attending each turn of affairs, ordered water to be pumped in by the -fire-engine. There was hard rain and strong wind; and telegrams which, -according to arrangement, were being frequently sent from Liverpool and -Plymouth, showed similar weather. This continued throughout the -Saturday, and the tide was low; but, when it began to rise in the -evening, it gave indications of being a very high one. As soon as the -tide reached the Kingston valves, Mr. Brunel had water run into the -ship. Although she rested uneasily on the cradles, she remained safely -in her position. - -In the evening the rain came down in torrents; nevertheless, after -midnight the weather mended, and the wind went round to the north-east. -As the telegraph gave the same report from Liverpool, Mr. Brunel, -encouraged by every sign of fine weather, and having the good promise -given by the high tide of the night before, determined early on the -morning of Sunday, January 31, to float the ship on that day. - -The pumps were immediately started to discharge the water from the ship. -The bolts securing the wedge-pieces of the cradles were unfastened at -daybreak, and the ship was then ready. - -The morning broke with great splendour after the gloom of the previous -days, and the tide, as soon as it had turned, began to rise with unusual -rapidity. It had been arranged that all the men should be at their posts -at the presses and crabs by eleven o'clock; but the tide was not only -very high, but exceptionally early; and, although a considerable margin -had been allowed, it was not sufficient. Mr. Brunel and his assistants -hurried the men to their places, the presses were set to work, and the -ship was put in motion down the ways for the last time. - -At a little before one o'clock observations taken by levels showed that -the ship had ceased to descend, although she was still being pushed -forward. Shortly afterwards Captain Harrison, who had gone on board, -sent Mr. Brunel word that all the wedge-pieces had floated up on the -outer side of the ship; and at twenty minutes past one the stern was -seen to be afloat. Mr. Brunel had been loath to haul out the ship by the -river tackle, lest the wedge-pieces might get jammed; but, as soon as he -was informed that they had floated up, he sent orders for a strain to be -put on the bow tackle. This was at once done, and by twenty minutes to -two the bow rose from the cradle. - -Mr. Brunel then ordered the checking gear to be secured, that the ship -might be sooner hauled clear of the cradles, and he went on board. He -had scarcely done so when a serious difficulty arose. It has been -already said, that in order to keep the ship from moving up or down -stream, cables had been carried out to moorings ahead and astern; and -both these chains had been hauled up tolerably taut, at least the slack -had been taken out of them, so that if required they might be at once -available. Now when Mr. Brunel had given the order for the bow out-haul -tackle to be hauled upon, Captain Harrison, in order to supplement it, -ordered the tug-boats to haul the bow off. This order was by some one -conceived to have been given with the object of hauling the ship ahead; -and to facilitate this the stern mooring-chain was let go. - -By this time, though the tide was still running up the river, its -strength was much diminished; and the drag of the chain at the bow of -the ship was sufficient to pull her forward against the tide. The -paddlewheel on the shore side then came in contact with the upright -timbers of the forward cradle. Mr. Brunel ran down from the ship into a -boat and examined the place where the wheel was fouled. He then hurried -back on board, where, as through some blunder the stern outhaul had also -been let go, he had now little but the tug-boats to depend upon. They -were of course of but small value for a dead pull as compared with the -chain tackle. He had the bow chain veered out and the tugs all set to -work, assisted by the tide, to haul the ship up the river. - -In about twenty minutes time, the paddlewheel was got clear of the -cradle, and this great difficulty was overcome. Fortunately, the tide -was an extraordinarily high one, and the time of available high water -was long. - - * * * * * - -The ship had not been moved far towards her berth when another mishap -delayed her progress. The barge of the bow purchase came foul of the -starboard paddlewheel, and the only way of freeing the ship was to -scuttle the barge. When this was done it sank away clear of the wheel, -and the ship proceeded to her berth on the Deptford side of the -river.[172] - - * * * * * - -By about seven o'clock she was safely moored; and the cheers of the men, -as Mr. Brunel went down her side, announced that the launch of the -'Great Eastern' was at length accomplished. - - -NOTE A (pp. 348, 368, 372). - -_Experiments and Observations on Friction._ - - In January 1857, Mr. Brunel took steps to form an estimate of the - amount of hauling or of retarding force that would probably be - required in the launch. - - Two rails were laid at an inclination of 1 in 12, and upon them an - experimental cradle was placed, with three cross-bars similar to - those which were to form the under surface of the cradles. The - three cross-bars therefore made six intersections on the two rails, - and the small cradle was loaded with about 8 tons, so that the - weight on each intersection was about equal to that which would - come on each of the intersections of the actual cradle. This - arrangement was not therefore a model, but a correct representation - of a part of the cradles, and which might, with an exception to be - noted presently, be taken to exactly represent, by its conduct, the - conduct of every similar part of the actual cradles. Experiments - were made with one or two kinds of unguents, and, what was a more - correct representation of what was likely to occur, with the rails - and bars clean but not bright, and without lubrication. - - The experiments with lubrication were useful rather as comparing - the various lubricants one with another than as representing, by a - mere process of multiplication, what would be the behaviour of the - ship on her cradles, because, for the reason already pointed out in - the case of wooden sliding-surfaces, the lubrication would be more - and more rubbed away as more of the cradle passed over it; thus the - experimental cradle, when tried with lubrication, represented - rather the behaviour of the front part of the cradle than that of - the whole. Had the ship herself been moved uninterruptedly down the - ways, the state of things would have been something between good - lubrication and none at all. As the under sides of the bars were - lubricated, any motion of one end of the ship before the other - would tend to move the bars sideways over the rails, and so to - spread the lubrication, and to pick it up and re-deposit it. Mr. - Brunel thought but little of the black-leading of the ways, - considering that it would be rubbed off by the leading bars of the - cradles; but a very little lubrication on metal surfaces is - sufficient; and doubtless, had the ship been moved continuously - down the ways, considerable assistance would have been derived from - the lubrication which was applied. - - The results of the experiment were curious. The generally received - notion is, that friction between rubbing surfaces is independent of - the velocity; that is to say, that whether a body be moving fast or - slow within reasonable limits, the retardation due to friction is - the same; that if a body be sliding at a given velocity, whether - that velocity be great or small, a drag of a certain number of - pounds will keep it moving at that velocity. It was, however, - always understood that a greater force was necessary to start a - body from rest, to overcome adhesion. The experiments made with the - experimental cradle distinctly showed that any rule as to friction - being constant at different velocities was untrue. It was evident - that, as the speed increased, the power required to overcome the - friction became less. No exact records are extant of the - experiments made with this experimental cradle before the launch; - they were, however, repeated during the launch with great care, and - the results very carefully analysed. The experiments showed - generally that the tractive force, including the action of gravity, - was never more than 1/8, or less than 1/15, of the weight. - - Although the experiments showed that the amount of friction in the - case of the actual launch would lie between the limits above - mentioned, they at the same time indicated that it would not - probably approach either of those limits. - - * * * * * - - Shortly after the commencement of the launch, Mr. Brunel had the - experimental cradle and ways re-erected. A very simple arrangement - was fitted up, by which the forces at work at each period of the - progress of the cradle in each experiment might be deduced. The - results of these experiments, which, as may be supposed, were - similar to those obtained in the commencement of the year, were - most instructive; they showed quantitatively the decided diminution - in friction which took place as the velocity increased, and the - amount of that diminution. The apparatus was very simple. The - experimental cradle, which has already been described, was made to - slide down its ways by a chain attached to a suspended weight. The - weight employed was generally about 5 cwt. After the cradle had run - a certain distance, the weight reached the ground and the cradle - proceeded with the momentum it had obtained. The velocity given to - the cradle down the ways was measured in the following manner. A - long piece of tape was coiled round a reel placed at the top of the - inclined rails or experimental ways, so that it could revolve - freely and pay out the tape as required. One end of this tape was - attached to the cradle, so as to be drawn after it as it ran down - the rails. The tape, as it ran off the reel, passed over a guiding - board over which swung transversely a pendulum arranged to swing - once every quarter of a second. At the lower end of this pendulum - was attached a brush which was filled with paint; and as soon as - the model cradle moved, the pendulum was set oscillating by a - self-acting trigger arrangement. The pendulum in its oscillations - made marks on the tape as it ran out at every quarter of a second - of time. Thus, by an examination of the tape, could be determined - the exact distance which had been passed over by the cradle during - each quarter of a second of the time during which it was moving. - The rate of progress being thus known, and the actuating force - (gravity acting on the cradle and on the suspended weight) being - also known, it will be understood that the exact amount of the - resisting force, namely, friction, could be calculated exactly, and - this for each moment and position of the descent of the - experimental cradle. - - The following results of these experiments were recorded in terms - of the corresponding amounts of tractive force that would be - required to produce similar results in the case of the ship and - cradles, a weight of 12,000 tons. - - - +------------------------------+-----------------------------+ - | | Force in tons required | - | | to move or restrain ship on | - | | incline of 1 in 12 | - +------------------------------+---+------+---+--+---+-------+ - |Velocity, feet per second | 0 |0 to 1|.75| 1|1.5| 2 to 3| - +------------------------------+---+------+---+--+---+-------+ - | RAILS AND CRADLE BARS. | | | | | |Retard-| - | | | | | | | ing | - | | | | | | |{ 110 | - |No. 1. Ample lubrication | | .. | ..|60| 0 |{ to | - | | | | | | |{ 200 | - |No. 2. Medium lubrication | | 120 | ..|..| 0 | 60 | - |No. 3. Very little lubrication|400| |200|..| 0 | .. | - | {| | 560 | | | | | - |No. 4. No lubrication {| | to | ..|..| 0 | .. | - | {| | 400 | | | | | - +------------------------------+---+------+---+--+---+-------+ - - +------------------------------+--------------------------------------+ - | | Force in tons required to move | - | | a weight equal to the ship on | - | | similar ways, but on the level | - +------------------------------+-----+------+-----+-----+-----+-------+ - |Velocity, feet per second | 0 |0 to 1| .75 | 1 | 1.5 | 2 to 3| - +------------------------------+-----+------+-----+-----+-----+-------+ - | RAILS AND CRADLE BARS. | | | | | | | - | | | | | | | | - | | | | | | |{ 890 | - |No. 1. Ample lubrication | | .. | .. |1,060|1,000|{ to | - | | | | | | |{ 800 | - |No. 2. Medium lubrication | | 1,220| .. | .. |1,000| 940 | - |No. 3. Very little lubrication|1,400| .. |1,200| .. |1,000| .. | - | {| | 1,560| | | | | - |No. 4. No lubrication {| | to | .. | .. |1,000| .. | - | {| | 1,400| | | | | - +------------------------------+-----+------+-----+-----+-----+-------+ - - In every case where a velocity approaching to 3 feet per second was - attained, whether the ways were lubricated or were quite dry, the - model, though there was no tractive force acting on it other than - that of gravity down the incline of 1 in 12, rapidly increased its - speed till it reached the end of the ways. - - These experiments are worthy of note for the contradiction, already - referred to, which they gave to the received rules relative to - friction. It will be seen by these experiments, and as will - hereinafter appear from the results of the movements of the ship - herself during the launch, that with different degrees of velocity - very great variation in the friction was apparent, amounting to a - difference of about thirty per cent. in the case of unlubricated - surfaces, according as the velocity was nearly _nil_ or was 1.5 - feet per second, which is a comparatively small velocity. The - friction in this case was, on a weight of 12,000 tons, 1,500 tons - at a very low velocity, and but 1,000 tons at a velocity of 1.5 - feet a second or about one mile an hour, the friction at the very - low velocity being fifty per cent. greater than that at one mile an - hour. - - As soon as the ship began to move by slides, the recording - apparatus of tape and pendulum was applied to record the nature of - the ship's movements. This apparatus was similar to that already - described. The tape was attached to the bottom of the ship under - her centre of gravity, and recorded the rate of retardation of the - ship when left to herself after the motive appliances had, with the - exception of gravity, ceased to act; and the amount of friction - acting to retard the ship was determined with a very considerable - amount of accuracy. - - The best experiments made were on December 7, 8, and 10; and the - results are very interesting. The dirt and rust of the sliding - surfaces had increased the adhesion very much, and a considerable - force was necessary to start the ship. There being no good pressure - gauges to the presses, it was impossible to decide exactly what was - the force required to start the ship, for of course the tape record - gave no information on this point; but there is no doubt it was - considerable, probably 800 or 1,000 tons in addition to gravity, - and was thus far greater than the force to start that had been - observed with the experimental cradle. - - But the remarkable fact was that, notwithstanding the deterioration - of the sliding-surfaces as evinced in the increased difficulty in - starting, the friction, when once motion was established, was - proved not to be very largely in excess of that which had been - exhibited in the experiments. - - In the various experiments tried, it was shown that when the ship - had a velocity of between 6 and 8 inches per second, the amount of - friction was only about 100 tons in excess of the action of gravity - down the incline; while as the velocity became less, the friction - became greater, till, as the velocity became smaller, the friction - increased from 200 to 300 tons in excess of the action of gravity. - - The results obtained by the observations made on the motion of the - ship having shown that its behaviour when in motion accorded with - that of the experimental cradle, there is every reason to believe - that if the ship had ever attained a velocity of 1-1/2 to 2 feet per - second, which might have happened had the river tackle acted well, - the friction would, as in the experimental cradle, have become less - than the action of gravity down the slope, and the brakes would - have had to be employed to check the motion. - - -NOTE B (p. 384). - -_Letter from Mr. Brunel to W. Froude, Esq._ - - - February 2, 1858. - - My dear Froude,--It is no news to you to tell you that we have - floated, but still you will perhaps feel sympathetically some - pleasure in hearing of it from me, as I do in writing to you upon - it. - - We have in fact gone on well and without mishap since we have - resumed operations with plenty of power; we have not gone very - quickly because our jumps have been small, or we have gone by a - continuous motion--we have had a great deal of this, and all the - last 30 or 40 feet I think, or more, has been so, the power being - _with_ gravity about a quarter of the weight, sometimes - less--occasionally, when the water was high, considerably - less--buoyancy being of course taken duly into the calculation. - Once, when still weighing fully 3,500 tons, and with 1,200 tons of - water in her, making 4,700, less some buoyancy of the cradle, she - moved so easily that they came running to me from the other cradle, - to say that she was moving of herself, and asking what to do. - - She certainly had not much more pressure on than we had assumed to - be necessary to overcome all the friction of thrust timbers, &c., - certainly could not have had above 300 tons of real push to move - - 2,000 - 2,000 tons, 2,000 -- ----- (gravity) = 1,833 tons. - 12 - - I think that when the load became much lighter on the rails, that - the mud and even the sand of the Thames form a lubricator and - _rollers_ which offered less resistance than the dry rail, or the - rail with pressure enough to displace the mud or imbed the sand. - - Having at last pushed the cradles beyond the rail, and found her - stand well, and moved a few feet more and still stand upright, I - waited for a tide, and arranged a good communication with - Liverpool and Plymouth to telegraph up wind and weather, morning - and night, so as to help in foreseeing a tide. - - On Friday morning, at 3 A.M., the tide began to improve, but the - wind was still in the wrong quarter for a good tide, and as I think - I have told you the tides of this month, and of the whole year of - '58, are very poor. Besides this, it blew a gale. I therefore began - pumping out the water, but stopped at 1,200 tons, and at 10 A.M., - seeing no improvement in the weather, I filled in by the - fire-engine about 1,300 or 1,400 more, and gave up the attempt, and - very fortunately, as the tide did not rise high enough, and the - wind right on her broadside increased. - - On Saturday night things grew worse, and the wind at Liverpool and - Falmouth finished in the evening still SSW. About midnight the wind - lulled, the rain came down in torrents; the wind gradually stole - round to the northward, and the tide came rolling up uncomfortably - quick. I admitted water as soon as it would run in, and only just - prevented her floating; when, if she had, we should have been in a - mess, as our wedge-pieces were not yet unbolted from the bottom, - nor could we in the night have managed the floating, even if all - had been ready, which nothing was. Under these circumstances, the - wedge-piece being bolted was perhaps our security, as she all but - floated; the stern rose 3 inches though we had 3,000 tons of water - in her, the tide rose so high; we began pumping immediately on the - turn of tide, and by half-past 6 A.M. the wind was gentle from the - NNE., and telegraphs came to announce the same in Liverpool, &c. I - therefore determined upon floating. - - We pumped away, and at 10 A.M. cleared everything away, and began - our preparations. I had fixed 12 o'clock to begin forcing her - further down, thinking half-past 12 would have been as early as she - would have moved easily, but the tide came rushing up an hour and a - half before its time; and, although I hurried the men to their - posts, we were rather caught napping. The instant we began - pressing, she moved easily, and by a quarter past 1 we had pushed - her centre past the ways, and she began lifting with the tide. - - I had a centre station with a chalk board, giving me the curve of - the tide, and two good levels reading off her stem and stern water - marks. Our calculations had proved very correct. In the skew - position I had pushed her to, she began lifting at the stern first, - as she ought to have done, and her bows soon followed the example. - We stopped pushing the cradles, made them fast, and began hauling - out the ship--she moved very slowly of course. - - When she began to move out, our first difficulty occurred by a - little mismanagement, or over confidence, on board; our stern chain - was let go, and she forged ahead against the tide by the elastic - strain of the bow chain, and _I think_ also by the tug-boats - pulling too much, which ought not to have been done, and in going - ahead her port paddles caught hold of some cradle timber rising, - with long 2-1/2 inch bolts holding them to the bottom of cradle. No - tug power would have had any effect upon them. But we had two hours - before us, with a promise of an unusual tide; I hurried on board, - and we succeeded in about twenty minutes in getting a little astern - a little out, and getting clear. - - We had some mishaps after this, such as fouling one of our barges, - getting it jammed under the paddlewheels, and the barge fast by the - chain tackle dropt overboard. However, we scuttled and sunk the - barge, and got safely across. We had an extraordinary tide, and - several assistances from nature to counteract any of our own - bungling, and got safely across, and she is now moored in her right - place. - - Yours faithfully, - - I. K. BRUNEL. - - William Froude, Esq. - - - - - - -CHAPTER XIII. - -_STEAM NAVIGATION--THE 'GREAT EASTERN' STEAM-SHIP._ - -_COMPLETION AND SUBSEQUENT HISTORY._ - -A.D. 1858-1859: AETATIS 52-54. - -A.D. 1859-1870. - - PREPARATIONS FOR COMPLETING THE SHIP--FORMATION OF THE GREAT SHIP - COMPANY--MR. BRUNEL'S ABSENCE FROM ENGLAND--PROGRESS OF THE WORKS - FROM HIS RETURN TO HIS LAST ILLNESS--VOYAGE TO WEYMOUTH--EXPLOSION - OF WATER-HEATER--STORM AT HOLYHEAD--DESCRIPTION OF THE SHIP--HER - FIRST VOYAGE TO NEW YORK, JUNE 1860--SECOND VOYAGE TO NEW YORK, MAY - 1861--VOYAGE WITH TROOPS TO QUEBEC, JUNE 1861--FRACTURE OF - RUDDER-HEAD AND DESTRUCTION OF PADDLEWHEELS, SEPTEMBER - 1861--VOYAGES IN 1862--ACCIDENT OFF MONTAUK POINT, AUGUST 27, - 1862--VOYAGES IN 1863--FORMATION OF THE GREAT EASTERN STEAM-SHIP - COMPANY--REMARKS ON THE HISTORY OF THE 'GREAT EASTERN' PREVIOUS TO - HER EMPLOYMENT IN LAYING SUBMARINE TELEGRAPH CABLES--TELEGRAPH - EXPEDITIONS OF 1865 AND 1866--FRENCH CABLE EXPEDITION OF - 1869--VOYAGE TO BOMBAY AND ADEN, 1869-70--CONCLUDING - REMARKS--_NOTE_: DIMENSIONS OF THE SHIP AND ENGINES. - - -Soon after the launch of the 'Great Eastern,' efforts were made to -obtain funds for finishing her, and Mr. Brunel proceeded to prepare -designs with the view of obtaining tenders for the execution of the -decks, skylights, fittings, rigging, &c. He obtained advice from persons -thoroughly conversant with this class of work; and a specification was -carefully prepared, providing for the completion of the ship in a -perfect manner. - - * * * * * - -Meanwhile it had been considered that, large as the ship was, she might -be profitably employed in the American trade, and that it might be -expedient to run her on that line for a few voyages before placing her -on the Eastern route. Captain Harrison went to America to examine the -harbour at Portland, and brought back a favourable report of it. - -All efforts to raise the funds for finishing the ship proved unavailing; -and it was determined to reconstitute the company. - - * * * * * - -The new company, which was called the 'Great Ship Company,' was formed -towards the end of the year 1858. In the beginning of December, Mr. -Brunel was compelled by ill-health to go to Egypt for the winter. On -leaving England, he strongly urged the Directors on no account to fail -to make a strict contract, distinctly defining the work to be done, and -the manner of its execution, as provided for by the specifications he -had drawn out. But his advice was not followed. - -After Mr. Brunel's return to England in May 1859, he continued to give -the greater part of his time to the ship. The difficulties which he had -to encounter were certainly neither fewer nor less vexatious than those -which had arisen at earlier periods in her history; but they were the -last with which he had to contend. - - * * * * * - -On September 5 he left her in the morning, feeling the commencement of -the illness which ten days afterwards terminated fatally. - - * * * * * - -The ship left her moorings on September 7, and with the assistance of -several tugs steamed down the river. She stopped for a night at -Purfleet, and again at the Nore, and then left for Weymouth. - -On the voyage a serious accident happened, which was made the subject of -much misrepresentation. - -Round each of the funnels of the paddle engines was what was termed a -water-casing, or jacket, consisting of an outer cylinder, about 6 inches -from the inner cylinder which formed the funnel. The top of the annular -space between the cylinders was at about the level of the deck. From it -a stand-pipe was carried up, which, after rising to a certain height, -was turned over, and the end brought down into the stokehole. The object -of this arrangement was to heat the feed-water before it entered the -boiler, and at the same time to keep the saloons cool, through which the -funnels passed. The arrangement of the stand-pipe gave this advantage, -that when the head of water in the heater and stand-pipe together became -equivalent to the pressure in the boiler, the water could be run into -the boiler by gravitation. The stand-pipe at the same time, being open -to the air at the top, formed a safety-valve to the water-heater. - -For the purpose of testing the joints of the jacket with water pressure, -while the ship was being finished, a stop-cock had been placed on the -stand-pipe, which unfortunately had not been afterwards removed. While -the ship was proceeding down Channel, the donkey feed-pumps were not -working well, and to ease them it was thought better to cut off the -water-heater, and to force the water direct into the boiler. The -communication of the water-heater with the boiler was therefore cut off; -and, as was afterwards ascertained, the stop-cock at the top of the -water-heater had been also closed. The water confined in the heater soon -produced steam, and when the ship was off Hastings the casing exploded. -The funnel was thrown up on to the deck, and a body of boiling water and -steam was driven down into the boiler room, severely injuring several of -the firemen, who afterwards died. - -That the effects of this accident were confined to one compartment of -the ship, was due to the complete protection afforded by the transverse -bulkheads. - -After she arrived at Weymouth the funnel was repaired; but as an outcry -was raised against the water-heaters, it was thought desirable, from -deference to public opinion, to discontinue their use; although this -accident had not in any way proved them to be objectionable, and they -are now generally adopted. - -While the 'Great Eastern' was at Weymouth Mr. Brunel died. - -Many visitors went in the ship when she left Weymouth on a trial trip to -Holyhead. At Holyhead she lay in a somewhat exposed situation; and the -sudden storm came on in which the 'Royal Charter' was lost. The great -advantage of having both paddle and screw was now, for the first time, -felt. A portion of the temporary staging erected by the contractor at -the breakwater was carried away, and drifted down upon the ship. During -the gale her engines were kept going, in order to relieve the strain on -the cables. The timbers of the staging got foul of both paddlewheels and -screw; but, as it was always possible to keep one of the engines at -work, the ship was saved from drifting. - -The season being now too far advanced for a profitable voyage to -America, the ship left Holyhead and went to Southampton Water for the -winter, where several alterations and additions were made. - -In Mr. Brunel's report of February 5, 1855, printed above, at p. 315, he -describes the leading features of the 'Great Eastern' as she was then -being constructed, but a more detailed account of them will fitly -precede the history of her career as a passenger-ship. - -The main arrangements of the ship are shown in the woodcut (fig. 16, p. -397).[173] - -The ship is 680 feet long, 83 feet wide, and 58 feet deep. Her gross -tonnage is 18,915 tons. She is divided into water-tight compartments by -ten bulkheads (_a_ and _b_), all of which, except two (_b_), extend -completely across the ship, and up to the upper deck. These two are -complete to 6 feet above the 28-foot water line. In addition there are -partial bulkheads (_c_), which form the ends of coal bunkers, and aid -materially in strengthening the flat bottom of the ship. The more -remarkable parts of the construction of the ship will be understood by -means of the transverse section. The bottom is made double, and between -the two skins are webs, running longitudinally. Mr. Brunel considered -that the double skin would greatly diminish the chance of such an -accident occurring as would cause any of the compartments to be filled -with water. The material being arranged in the direction of the length -of the ship is all capable of taking part in the strains that are thrown -on the bottom, as well as on the top, by forces tending to bend the -ship. - -Mr. Brunel also made the upper deck cellular, in order to resist the -compressive strain that would come on it when the ship was heavily -loaded in the middle of her length. Great additional strength to the -ship, considered as a girder, is given by two longitudinal bulkheads, 36 -feet apart, extending for 350 feet. These bulkheads, with the sides of -the ship, form the vertical web plates of the girder. Her structure -resembles the tubes of the Britannia bridge; the cellular top flange -being connected with the cellular bottom flange by plate-iron webs. - -[Illustration: Fig. 16. _Longitudinal Section_ - -_Plan showing Machinery and Coals_ - -_Midship Section showing Cabins and Boiler Room._ - -'GREAT EASTERN' STEAM-SHIP - - _a._ Complete transverse watertight bulkhead - _b._ Transverse watertight bulkheads complete up to water line - _c._ Partial transverse bulkheads - _d._ Longitudinal bulkheads - E. Cable decks - F. Chain cable lockers, &c. - G. Ice-house, stores, &c. - H. Forward cargo space - I. Paddle boiler rooms - J. Paddle engines - K. Cross coal bunkers - L. Paddle auxiliary engines - M. Screw boiler rooms - N. Screw engines - O. Screw auxiliary engines - P. Screw alley - Q. Grand saloon - R. Ladies' saloon -S,U. Lower saloons - T. Upper saloons - V. Passage tunnel - W. Steam-pipe tunnel - X. Aft cargo space - Y. Aft cable deck, &c. - Y'. Deck for auxiliary tiller, &c. - Z. Cabins - -NOTE.--_The masts of the ship, six in number, are not shown on this -woodcut._] - -The two skins of the ship, with the web plates between them, forming the -cellular bottom of the great girder, may also be considered as a number -of smaller girders placed side by side, each resisting the excess of the -pressure of the water over the load that may happen to be resting on it -inside the ship. The difference of pressure or upward strain is -transmitted by the cross bulkheads (_a_, _b_, _c_) from the bottom of -the ship to the sides and longitudinal bulkheads. - -The double skin extends up to about 6 feet above the water level -throughout the whole length of the ship, with the exception of the -extreme ends. - -The foremost compartment next the bow has two cable decks (E), with -capstans and all the necessary riding-bitts, stoppers, and other -appliances for working the cables. These arrangements answer well, and -the 3-inch chain cables are worked with great facility. The capstans -were originally driven by a shaft from the paddle auxiliary engines, but -this was found inconvenient, and a small independent engine has been put -to work them. The cables are stowed in chain lockers on a deck (F) below -the cable decks, and below this (G) are ice-houses and store-rooms. The -next compartment of the ship (H) is intended for cargo. It is at present -occupied by the forward cable tank. - -The main part of the ship, 350 feet in length, up to the level of the -lower deck, 34 feet above the bottom, is occupied with her engines, -boilers, and coal bunkers. The space above the lower deck was occupied -with saloons and cabins for passengers, except at the paddle engine room -(J). The boilers, four in number, two in each boiler room (I), which -supply steam to the paddle engines, are placed forward of the engines; -and forward of the boiler rooms is a coal bunker (K), 20 feet long; and -abaft of the paddle engines are the six boilers, two in each boiler room -(M), that supply steam to the screw engines (N). These three boiler -rooms are separated by coal bunkers (K), 20 feet long. On either side of -the boilers and engines, and also upon plate iron arches above the -boilers, are bunkers for coal. This will be seen on the transverse -section of the ship. Between the paddle engines and boilers is a -water-tight compartment, 10 feet long (L), in which are placed a pair of -auxiliary engines of sixty horse-power, which pump water out of the ship -and also work fire-pumps. There are two other auxiliary engines of sixty -horse-power in a compartment (O) aft of the screw engines, intended to -keep the screw propeller turning round, either when the ship is at -anchor, to relieve the strain on the cables, or when, for any reason, -she is only using her paddle engines. They also work bilge-pumps and -fire-pumps. Each set of auxiliary engines has two independent -high-pressure boilers. Throughout the bottom of the ship there are two -bilge-pipes, fitted with valves, with branch-pipes leading to the -various compartments of the double skin. These bilge-pipes can be -connected with either of the auxiliary engines, and so the water can be -pumped out of any part of the ship. - -The paddle engines, of 1,000 nominal horse-power, consist of four -inclined oscillating cylinders, 14 feet stroke and 6 feet 2 inches -diameter, each pair of which work on to a single crank. There are means -for disengaging either paddlewheel from the engines. - -The screw engines, of 1,600 nominal horse-power, consist of four fixed -horizontal cylinders, 4 feet stroke and 7 feet diameter, the two -cylinders of each pair working opposite to each other on one crank. - -In each boiler room are two donkey engines for supplying the boilers -with water, and the main engines are also fitted with feed-pumps. Each -of the donkey engines is capable of pumping water out of the ship, and -of being used in case of fire. - -The screw shaft passes along what is termed a screw alley (P). The -weight of the screw rests on the bearing where the screw shaft passes -out through the stern-post of the ship. To prevent the water that leaks -in through this bearing from penetrating into the screw alley, there is -a bulkhead with a stuffing-box round the screw shaft, a short distance -forward of the stern-post. To enable access to be gained to the bearing, -a tube was provided leading down from the main-deck. This was intended -to be fitted with appliances for pumping air in so as to drive the water -out, and to admit men to get at the bearing under air pressure. - -Another arrangement was also provided for the same purpose. On the after -side of the stern-post was placed a ring of india-rubber; and, by -pulling in the screw-shaft, the screw was pressed tightly against the -india-rubber ring, which prevented the water from entering. By means of -this arrangement the stern-bearing was examined and repaired at -Southampton. - -The screw propeller has four blades, and is 24 feet in diameter and 44 -feet pitch. The paddlewheels were 56 feet in diameter, with 30 floats, -each 13 feet broad and 3 feet deep. - -Over the boiler rooms run two tunnels; one of them (V) serves as a -passage to enable the engineers to pass from one compartment to another -throughout the part of the ship occupied by the boilers and engines. The -openings leading from the tunnel to the engine or boiler rooms are -provided with watertight doors, which can be shut in the event of any of -the compartments getting full of water. The other tunnel (W) serves as a -passage for the steampipe, which leads from the boilers to the engines. -Though the boilers are divided into two sets, one for the paddle engines -and one for the screw, the steampipes are connected, so that the whole -of the ten boilers, or any of them, may be used to supply steam for -either of the engines. - -In one point a deviation was made from Mr. Brunel's arrangements. It was -his intention that there should be no apertures in the water-tight -bulkheads except at the tunnel (V), from which the various boiler and -engine rooms were to be entered by openings, to be closed by water-tight -doors. The tunnel was placed high up, so that in the event of a leak -there might be ample time to close the door. The inconvenience of -ascending and descending by ladders was, however, considered an evil; -and it was found necessary at times to carry coals from one compartment -to another. For these reasons, upon the requirement of the Board of -Trade, doorways, fitted with sliding doors, which can be closed by -handles on the upper deck, have been cut in the bulkheads between the -boiler rooms. This arrangement exists in other ships; and in the 'Great -Eastern,' even without closing these doors, there are eight watertight -compartments. - -At the stern of the ship (Y) on the main-deck are arrangements for -working cables, similar to those at the bow. - -These appliances are required when the ship has to be moored so as not -to swing with the tide; and they would allow of the ship's riding by the -stern instead of by the bow, which it might often be useful for her to -do in narrow waters. On the lower deck (Y), at the stern of the ship, is -a spare tiller and wheel for working the rudder, in case anything goes -wrong with the main tiller, which is on the upper deck. The weight of -the rudder is carried on the lower deck by a grooved collar, resting on -a ring of cannon balls. - -The compartment (X) immediately aft of the screw engine room is for -cargo. - -The saloons and cabins are all in the middle of the length of the ship, -where there is least motion. The usual plan of putting the first-class -passengers at the stern was not adopted, and they were placed forward. -As the smoke generally drifts towards the stern of a ship, the -first-class passengers in the 'Great Eastern' are not annoyed by the -smoke, or by the dust and smell from the boiler and engine rooms. - -The transverse section shows the arrangement of the cabins. - -Mr. Brunel intended that the upper saloons (T) should be used as -sitting-rooms, and the lower saloons (S and U) as dining-rooms. These -were to be lit and ventilated by shafts on either side of the upper -saloons, rising up to the skylights on deck. The smell of dinner was -thus to be kept away from the sitting-rooms. The cabins (Z) on either -side were to be approached from the saloons by passages and steps, as -shown on the section. The saloon marked (Q) is the first-class, and (R) -the ladies' saloon. - -The ship is rigged with six masts. The arrangements of the masts and -rigging were especially intended for the Eastern voyages. At the extreme -bow and stern are low masts, which carry trysails and staysails. The -sails on these masts were chiefly intended for manoeuvring the ship. -She also has three large masts, the lower masts being of iron. The two -foremost of these are square-rigged, and all three of them have trysails -and staysails. The aftermost of the three was also made strong enough to -be fitted with square yards, in the event of its being desirable to rig -it in that manner. Aft of the three principal masts is a large mast, -only intended to be rigged with fore-and-aft canvas. The ship has no -bowsprit, the stay of the foremost mast being attached to the stem -inside the bulwarks. - - * * * * * - -In the beginning of June 1860, the ship made a trip from Southampton -down the Channel, as far as the Start Lighthouse and back, to try her -engines; and on June 17 she sailed for New York, under the command of -Captain Vine Hall, who had succeeded Captain Harrison. She arrived -there, after a prosperous voyage, on June 28, and was received with -great enthusiasm. The ship left New York on August 16, and, having -called at Halifax, arrived at Milford Haven on August 26. - -In the course of these two voyages the stern-bearing of the screw-shaft, -which was in white metal, had worn down between two and three inches. -With the view of allowing for any depression of the stern-bearing, the -lengths of the screw-shaft were not rigidly connected throughout, but -the end length, attached to the screw, was coupled to the remainder of -the shaft by a universal joint, consisting of two double cranks. Thus -the two shafts might be, to a considerable extent, out of line, and yet -revolve efficiently. - -When the ship returned to Milford Haven, a gridiron was prepared on the -beach, and she was grounded on it; and the screw-shaft was drawn in. By -this time it had become the general opinion that a shaft cased with -brass, and running in lignum-vitae bearings, was the best. A lathe and -machinery for making the shaft revolve were provided, and fixed in the -stern of the ship; the shaft was turned, and brass collars shrunk on. -The bearing was made with lignum-vitae, and the brass-covered shaft -replaced in it. It has since worked well, and has shown no signs of -wear. - -The ship, commanded by Captain William Thompson, left Milford Haven for -New York on May 1, 1861, and returned to Liverpool from New York on June -4, having made an average speed of 13-3/4 knots on the outward and 14 knots -on the homeward voyage. - -At this time the Government determined to send her out with troops to -Quebec, and she was fitted up for that purpose. She took upwards of -2,500 troops, and about 40 passengers. There were, altogether, about -3,000 persons on board, and 200 artillery horses. Scarcely any of the -troops were placed in the regular passenger part of the ship, as they -were accommodated in the cargo departments (H, X). Thus a much greater -number of men might have been carried in her with perfect comfort. She -was commanded on this voyage by Captain James Kennedy, of the Inman -service. She left Liverpool on June 27, and arrived at Quebec on July 7. -She returned to Liverpool with about 500 passengers in August. - -By this time her superiority had become recognised by the regular -travellers between England and America. Those who had been in her found -that, while they passed other ships rolling and pitching in the sea, the -deck of the 'Great Eastern' was so steady that it was difficult to -believe that there was a gale blowing;[174] and when, after a -continuance of heavy weather, she began to roll, the motion was so slow -and easy as to be comparatively unimportant. - -When she left Liverpool again, there were a considerable number of -passengers, and it seemed as if her success was ensured. She started -under the command of Captain James Walker, on September 10, and three -days afterwards encountered a severe Atlantic gale. - -The ship was behaving well, when one of the boats, which hung on davits -outside the ship forward of the paddlewheels, got adrift on the weather -side. Fears were entertained that it might foul the paddlewheel, and the -captain determined to cut it away. The direction of the ship was -altered, in order that the boat might float clear. The ship then resumed -her course; but shortly afterwards fell off, with her broadside to the -sea. - -Relieving tackles having been put to assist the men at the wheel, the -tiller was kept hard over, to bring the ship's head to the wind; but -with no effect. Towards evening, as the seas beat heavily against her -side, first one paddlewheel and then the other was destroyed, being -completely torn away from the central bosses. During the night she lay -in a helpless condition. The gale had been of some duration, and the -waves being large and long, the ship was placed in a very unfavourable -position to receive them; and she rolled considerably. - -The next morning, when an officer went to examine the auxiliary tiller -on the lower deck, he discovered that the rudder-head was twisted short -off, just above the point where it entered the ship. The rudder was -still in its place. The accident had most likely happened on the -previous evening, when the ship fell off her course. It had not been -noticed by the men at the helm, perhaps because there were so many of -them at the wheel and relieving-tackles that they held one against the -other; and the broken parts of the rudder-head, grinding together, threw -jerks on to the tiller. The fracture of the rudder-head was caused by -the badness of the workmanship in the interior of the forging. - -Attempts were made to get sail on the ship, but without much success; -and with the hope of bringing her head to wind, the screw engines were -reversed. - -As soon as the ship was driven astern by the screw, the rudder, being -uncontrolled, was forced round by the rush of water, and it knocked -away the after stern-post.[175] No other harm was done, as the rudder is -secured by a pin into the heel of the ship, and by a collar round the -rudder-head, attached to the hull above water. - -Steps were then taken to get command over the rudder. Chains were -wrapped round the stump of the rudder-head inside the ship, and a -certain amount of control was thus obtained. A more effective plan was -at the same time carried into execution. A man was lowered by a rope -from the stern of the ship, who hove a piece of wood, with a line -attached to it, through the screw-opening. The wood with the end of the -line was caught with a boat-hook; and a rope, and afterwards a hawser, -and then a piece of the ship's chain cable were passed through behind -the rudder. The two ends of the chain cable were brought together at the -stern of the ship, and a large shackle put round both parts of the -chain, and shaken down till it held them together. In the edge of the -rudder-blade a notch had been made by the rudder striking against the -screw, and into this notch the shackle was made to drop. In this way two -chains or pennants had been attached to the back of the rudder. One of -these was brought to each side of the ship, and they were hauled on by -means of the stern capstan. - -The ship then turned homeward, and the weather having moderated, she -arrived off Cork harbour on the afternoon of September 17. By this time -the chains round the rudder had shifted, and were of little service; and -before night it began to blow heavily towards the shore. It was -dangerous for the ship to remain on a lee shore; and, although the -steering-gear was out of order, the captain wisely determined to take -advantage of the ship's head pointing in the right direction, and -steamed out to sea. - -Three days afterwards the ship, assisted by several small steamers, was -got safely into Cork harbour, a temporary tiller was attached to the -stump of the rudder-head, and she proceeded to Milford Haven, where she -was placed on the gridiron, and her after stern-post and paddlewheels -replaced. The accident had proved that the original paddlewheels might -with advantage have been made stronger, and in the new wheels the -bracing was increased. - - * * * * * - -The ship, under the command of Captain Walter Paton, left Milford Haven -for New York on May 7, 1862, and returned to Liverpool on June 11. She -left again on July 1, and returned on August 6. Besides the number of -passengers the ship accommodated, she carried a considerable amount of -cargo; she brought over large quantities of grain and provisions. The -custom of carrying this class of freight in steam-ships received a great -impulse from the success of the 'Great Eastern' in the traffic. As it -was found that the shallowness of the bar at Sandy Hook prevented her -taking full advantage of her carrying power, she had on this voyage -followed the route along Long Island Sound, so as to arrive close to New -York in deep water, and on her return voyage she brought as much as -5,300 tons of cargo in bulk, which with 4,350 tons of coal gave her a -mean draught of 28 feet. - -She left Liverpool on August 17, and arrived off Montauk Point, at the -entrance to Long Island Sound, at about two in the morning of the 27th, -to take in the pilot. While stopping, a loud rumbling noise was heard, -and presently the ship heeled slightly over to one side. The pilot, -when he came on board, said that the ship had passed over a reef of -sunken rocks, which was not marked on the charts. - -It was at the same time found that many of the spaces between the double -skins were full of water. The ship went on to New York, and most of the -passengers landed in ignorance of an accident which in any other vessel -would have been fatal. - - * * * * * - -Steps were at once taken to examine the damage, and the divers reported -a large fracture in the outer skin 80 feet long and about 10 feet broad. -They also discovered afterwards several smaller fractures. It was -considered that this damage might be mended while the vessel was afloat, -and a very skilful arrangement, contrived by Messrs. Renwick, of New -York, was adopted. A large wooden barge was made with a gunwale shaped -to fit the ship's side, and two wooden passages leading down into the -barge. It was placed so as to cover the large fracture, and was secured -by chains passed round the bottom of the ship. The joint between the -gunwale of the barge and the ship's side was made water-tight; the water -was pumped out, and men and materials passed down through the shafts. By -the exertions of those engaged in this difficult operation, the great -fracture was repaired, and the ship returned to England in the beginning -of 1863. - -A gridiron was made at Birkenhead; the ship was placed on it, and the -repairs were proceeded with under the direction of Mr. Brereton, who at -Mr. Brunel's death succeeded him as engineer to the Great Ship Company. -On examination, it was found that fractures had been made in ten -separate places in the outer skin. - -The ship started again in May 1863, and made three voyages to New York -and home. At this time, however, there was a severe competition with -other vessels, and the Company could not afford to run the ship -unremuneratively for any length of time. In 1864 she passed into the -hands of a new company, which consisted almost entirely of those who, -from their belief in the capabilities of the ship, had found the money -for starting her again after each of her successive misfortunes. - -The ship lay idle for some months, and was then chartered by the -Telegraph Construction and Maintenance Company. - - * * * * * - -The 'Great Eastern' had in the course of the four years from 1860 to -1863 made nine voyages across the Atlantic and back. Though this was not -the route for which she had been intended, it had given her many -opportunities of showing her merits. Adverse fortune had added to these -opportunities, and had at the same time demonstrated the necessity of -many of the precautions which Mr. Brunel had taken to ensure her safety. - - * * * * * - -The construction of the hull of the ship has been proved by experience -to possess the advantages anticipated by Mr. Brunel. - -Its strength as a whole has been proved by the absence of all signs of -weakness in the heavy weather she encountered on several occasions, and -especially in the gale of 1861, when her rudder was disabled. The -strength of the ship has since been fully tested by the enormous loads -she has carried while on telegraph cable expeditions. - -The importance of the double skin was shown on the occasion of her -grinding over the rocks at Montauk Point, when so large a number of -leaks were made in all parts of her bottom that no ordinary system of -bulkheads would have saved her from foundering. Moreover, the space -between the two skins was sufficient to allow of the outer skin and the -webs being crushed to the extent of three feet, while they at the same -time acted as a buffer and prevented the inner skin from coming in -contact with the rock. - -The engines have not had any opportunity of working at high speed in the -long voyages for which they were intended, but in the rapid and -comparatively short passages made by the ship across the Atlantic they -worked with great regularity and success. Although they were commenced -seventeen years ago, they are still fine specimens of marine engines, -and bear witness to the care taken by their builders in their design and -manufacture. - -Of the points on which Mr. Brunel laid stress, and which, as he -remarked, 'involve no other risk than that of being useless; they cannot -do mischief,' many have now come to be considered essential parts of -good marine engines. He thought it of great importance that the steam -cylinders should be jacketed, especially at the ends; and it was -intended that the high-pressure steam for this purpose should be taken -from the auxiliary boilers. This plan was, however, not adopted. - -Mr. Brunel was also anxious that the steam should be heated immediately -before it entered the cylinders, and that fresh water should be supplied -for the boilers by using the same water over again. Arrangements for -effecting these objects have since been brought into general use. - -The advantage of having several cylinders to each engine was shown while -the ship was running to America. Part of the valve-gear of one of the -paddle-engine cylinders gave way, the engines were stopped for four -hours, and the ship was propelled by the screw alone. The cylinder was -disconnected and turned back out of the way, and the engines worked -efficiently with three cylinders for four passages across the Atlantic. - -The average speed of the ship on those voyages in which her performances -were fairly tested was about 13-1/2 knots. On two occasions she made the -voyage from New York to Liverpool at an average speed of 14 knots; and -she maintained her speed in rough weather and head winds to a much -greater extent than is the case in smaller vessels. - -By having two sets of engines, the ship was saved from serious disaster -at Holyhead, and again in the gale of September 1861. - -The great handiness of the ship is one of the many beneficial results of -the use of both paddles and screw. By working the paddlewheels astern -and the screw ahead, she can be kept from moving forward or backward, -and at the same time the stream of water from the screw, acting on the -rudder, makes her answer her helm and turn round on her centre. By -modifying the speed of the two engines, she may be made to creep slowly -forward; and as the rudder is in the full rush of the water driven back -by the screw, the ship has practically as much steering power as she has -when moving rapidly. The importance of this power of controlling her -when passing through narrow channels, in entering and leaving port, can -scarcely be over-estimated. - - * * * * * - -The career of the 'Great Eastern' since the formation of the present -Great Eastern Steam-Ship Company, has been prosperous. - -In the commencement of the year 1864, when Mr. Cyrus Field had succeeded -in reviving the project of laying the Atlantic cable, the Telegraph -Construction and Maintenance Company took the contract for laying it, -and hired the 'Great Eastern.' She was brought round to Sheerness, -where the cable tanks were fitted into her. One tank was placed in the -forward cargo compartment, and another in the after cargo compartment; -and the largest tank was placed over the middle screw boiler room, the -funnel being removed. Therefore, during the cable-laying expeditions, -the ship only used eight of her boilers. - - * * * * * - -The history of the laying of the Atlantic cable is well known. The -'Great Eastern' started from Valentia on June 23, 1865, under the -command of Captain (now Sir James) Anderson, and the cable was laid more -than half way across the Atlantic; but, on hauling in to recover a -fault, it was broken, and dropped to the bottom of the sea. - -The grappling tackle was not sufficiently strong. The cable was three -times partially raised, and each time lost; and the expedition returned -to England defeated, but with the knowledge that ultimate success was -certain. - -The engineers and scientific men on board the 'Great Eastern' drew up a -memorandum as to the results of this expedition, and, among other -things, stated--'That the steam-ship "Great Eastern," from her size and -constant steadiness, and from the control over her afforded by the joint -use of paddles and screw, renders it safe to lay an Atlantic cable in -any weather.'[176] - -Sufficient additional cable was made to lay a second one and to finish -the old cable when it should be recovered. The ship started again on -July 13, 1866, and laid the cable across the Atlantic without the -slightest mishap. She then returned, and after three weeks of hard work, -the end of the cable which had been lost the year before was picked up, -and completed to Newfoundland. - -On her return to England there did not seem to be any immediate -employment for her in cable laying, and the tanks were taken out. In the -following year a company was formed in France to charter the ship, and -to work her between New York and Brest during the French Exhibition. She -made one voyage from Liverpool to New York and back to Brest and -Liverpool; but the undertaking was a commercial failure. - -She remained at Liverpool till October 1868, when it was proposed to lay -a cable from France to America; and she came round to her former berth -at Sheerness. Tanks were made in the fore and aft cargo spaces, and a -very large tank, 75 feet in diameter, was placed amidships. The -bulkheads were cut partially away to make room for it, the ship being -strengthened above and below. She started on this expedition from Brest -under the command of Captain Robert Halpin, and encountered very heavy -weather. The cable was laid successfully. - - * * * * * - -The ship then returned to England, and was fitted out for the greatest -adventure she has yet undertaken. She was to proceed with a full cargo -of cable round the Cape of Good Hope to Bombay, to lay it thence to -Aden, and from Aden a portion of the way up the Red Sea. With her cable -and coals, on leaving England, she drew 34 feet 6 inches, with the -enormous displacement of 32,724 tons. She laid the cable with perfect -success, and returned to England. - - * * * * * - -Throughout all these cable-laying expeditions, and especially in the -work of picking up the Atlantic cable of 1865, the good qualities of the -ship have been fully exhibited. - - * * * * * - -The later voyages of the 'Great Eastern' were undertaken for the -accomplishment of a work in which Mr. Brunel had felt a great interest. - -In 1856, Mr. Cyrus Field came over to this country in order to consult -English engineers and scientific men upon his project of an Atlantic -cable. It is stated in a work written by Dr. Field,[177] that-- - - From the beginning Mr. Brunel showed the warmest interest in the - undertaking, and made many suggestions in regard to the form of the - cable and the manner in which it should be laid. He was then - building the 'Great Eastern,' and one day he took Mr. Field down to - Blackwall to see it, and said, 'There is the ship to lay the - Atlantic cable.' - -It appears, however, from drawings in Mr. Brunel's sketch-books that at -this time, and again in 1858, he thought that it would be better to -have a vessel specially built for the work. - -He was throughout sanguine as to the ultimate success of the -undertaking, as is shown by the following extract from a letter written -in December 1856:-- - - I would suggest a more moderate expression of doubts of the - successful results of the American cable. The impossibility of - running steamers profitably over the surface of the same sea was, - though it is now denied, asserted and proved from established facts - just as clearly as the impossibility asserted now to exist in - respect of the electric telegraph. It is a pity in these days to - lay down any such dogma. Every day's experience proves that - nine-tenths of them are refuted; that the circumstances do not - prove to be such as are assumed, or the difficulties are overcome; - and however correct the arguments may have been, the result is not - as predicted. - -The 'Great Eastern' has not yet been engaged on the work for which she -was originally designed by Mr. Brunel; but her employment in the -promotion of great scientific enterprises has been an occupation worthy -of her connection with his name. - - -NOTE (p. 395). - -_Dimensions of the 'Great Eastern' Steam-ship._ - - Extreme length, 693 feet - - Length between perpendiculars, 680 " - - Breadth, 83 " - - Depth, 58 " - - Greatest draught of water, 30 " - - Registered tonnage, 13,343 tons - - Gross tonnage, 18,915 " - - Displacement at 30 feet draught, 27,419 " - -DIMENSIONS OF PADDLE-ENGINES. - -(1,000 nominal horse-power.) - - Number of cylinders, 4 - - Diameter of cylinders, 6 feet 2 inches - - Length of stroke, 14 feet - - Number of boilers, 4 - -DIMENSIONS OF SCREW-ENGINES. - -(1,600 nominal horse-power.) - - Number of cylinders, 4 - - Diameter of cylinders, 7 feet - - Length of stroke, 4 " - - Number of boilers, 6 - - - - -CHAPTER XIV. - -_DOCK AND PIER WORKS._ - -A.D. 1831--1859. AETATIS 26--54. - - MONKWEARMOUTH DOCKS, 1831--BRISTOL DOCKS, FLOATING HARBOUR, - 1832--PROPOSED WORKS AT PORTISHEAD--NEW LOCK AT BRISTOL, - 1845--PLYMOUTH GREAT WESTERN DOCKS, 1847--BRITON FERRY DOCKS, - 1851--BRENTFORD DOCK, 1856--PIER AT MILFORD HAVEN, 1857. - - -Mr. Brunel's dock and pier works are interesting, not only in their -general features, but also in the details of their construction; and the -plans he made for large docks at Monkwearmouth in 1831, which he carried -out on a smaller scale shortly afterwards, were among the earliest of -his independent designs. - -With the exception of the gates of this dock, which are of timber, all -the dock gates Mr. Brunel constructed are of wrought iron. This material -had been employed in ship-building before Mr. Brunel adopted it for the -gates of the new lock at Bristol, and it was also beginning to be -extensively used for bridge girders. - -At the same time that he introduced the use of wrought iron into dock -gates, he constructed them with a large amount of buoyancy, in order -that they might be moved easily, while being opened and shut. - -The dock and pier works which he constructed are at Monkwearmouth, -Bristol, Plymouth, Briton Ferry, Brentford, and at Neyland, Milford -Haven. They will be described in this order, which is nearly that of -the dates of their construction. - - -_Monkwearmouth Docks._ - -The town of Monkwearmouth is situated at the mouth of the river Wear, on -the north side, and opposite to the towns of Sunderland and -Bishopwearmouth, which extend for about a mile along the south side. In -order to improve the entrance of the river, and to diminish the -sand-banks which lay near its mouth, piers were proposed as early as the -middle of the last century, and were partly built on both sides of the -river before the year 1800. From that date until 1831, although the -question of making docks had been considered, and designs proposed by -different engineers, no steps had been taken for their construction, and -the only works executed for the improvement of the port were the -extension and alteration of the piers already existing. In 1831 designs -for docks to accommodate the increasing traffic were made simultaneously -by Mr. Brunel and Mr. Giles. Mr. Brunel's docks were to have been on the -north side of the river, and to have had an area of 25 acres, with -quays, warehouses, &c. Mr. Giles's were to have been on the south side. - -Neither of these schemes was approved of by Parliament; but shortly -afterwards a private company was formed for the construction of a dock -on a plan designed by Mr. Brunel, though on a much smaller scale than -his scheme of 1831, the dock being only about 6 acres in area, with a -tidal basin of about an acre and a half. The company encountered -considerable opposition from the authorities of the town of Sunderland, -but succeeded in obtaining a royal charter for the construction of the -dock. They subsequently obtained an Act of Parliament empowering them -to make the entrance from the dock to the river. The dock was -constructed, and eventually became the property of the North Eastern -Railway Company, to whom it now belongs; they have erected coal drops -along the quay, and have made it a shipping place for collieries -connected with their railway. - -The work was begun in 1834, and the dock and tidal basin occupy part of -the site chosen by Mr. Brunel for his larger scheme of 1831. - -The quay wall was built with a curved batter, the chord line joining the -top and bottom having an inclination of 1 in 5. The masonry was carried -up in courses, and made solid by filling every part thoroughly with -mortar. A course at the face and at the back of the wall was built up; -an abundance of mortar was then spread in the heart of the wall, and the -stones built in the mortar. Thus no crevices could be left in any part -of the work, and the back of the wall was soundly built throughout. - -The entrance to the dock is 45 feet wide, with side walls of the same -profile as the quay wall. Except at the gate floors, there is a -segmental invert of dressed stone of such curvature that it is 6 feet 6 -inches lower in the middle than at the side walls. The gate floors are -formed with inverts, curved to correspond with the under sides of the -gates. - -The masonry of the entrance was executed within a four-sided coffer-dam, -the sides of which were slightly convex outwards. This coffer-dam was -constructed in the usual way, there being two rows of close piling with -puddle between them; and it was strengthened by internal horizontal -shores which connected the opposite sides, and by diagonal bracing. The -piles were driven until they met with so much resistance as to render it -unsafe to drive them farther. When the ground inside the coffer-dam was -excavated, it was found that the piles had been driven into sand and -gravel, and that, to enable the masonry to be built on a good -foundation, it would be necessary to excavate about 7 or 8 feet below -the piles. They were therefore driven down gradually, as the ground was -removed from the inside, until the requisite depth was obtained. The -whole coffer-dam was thus an immense caisson, the sides of which were -lowered by gradual driving, instead of being simultaneously forced down -by weights. - -The masonry of the walls of the tidal basin is similar to that of the -walls of the dock; some parts of the foundation were laid by means of a -diving-bell. - -In the entrance between the dock and the tidal basin there is a pair of -gates pointing inwards, which serves to retain the water in the dock -during the fall of the tide, and there is also a pair of storm gates -pointing outwards, which protects the inner pair from the force of the -waves. - -The construction of both pairs of gates is similar. - -The two leaves of each pair meet at an angle of 125 deg.. Each leaf is about -30 feet long; the bottom beams are curved to the form of the segment of -a circle; the height at the meeting-post is 27 feet, and at the heel -post 22 feet (see woodcut, fig. 17). This arrangement is, to a greater -or less extent, followed in the dock gates Mr. Brunel afterwards -constructed. By raising the pivot, the gate floor can be made of ample -strength, and the cills and heel-posts are free from mud and deposit. -The gates are constructed of horizontal beams of yellow pine timber, 21 -inches thick, placed close together for a height of 12 feet above the -bottom. Above this there are beams of timber and of cast iron at -intervals. The whole is planked over on the inner side with 4-inch -planking. The heel-post and meeting-post are socketed into cast-iron -uprights, which also receive the ends of the horizontal beams. To -preserve the gate from any change of form, a diagonal iron tie-bar -extends from the top of the heel-post to the timber beams forming the -lower part of the gate. - -[Illustration: Fig. 17. Monkwearmouth Dock Gates. - -_Elevation. Section. - -Plan. - -Scale of feet._] - -Nearly under each meeting-post is placed a bevelled cast-iron wheel, 18 -inches in diameter, which supports part of the weight of the gate. - -There are four sluices in each leaf, placed in pairs, with a small -interval between them. Each pair of sluices counterbalances the weight -of the other pair by being attached to opposite ends of a lever at the -top of the gate. A screw works in the segment of a large worm-wheel -formed on the end of the lever, and, being turned round, opens and shuts -the sluices. After the timber work of the gate had been fitted together, -it was taken to pieces, and subjected to the preserving process called -Kyanising, which consists in immersing the wood in a solution of -corrosive sublimate. This process has been so successful, that when the -gates were recently taken out for examination the timber was found to -be nearly perfect, only slight surface repairs being required in one or -two places. - -The great bulk of light wood at the bottom of these gates gives them a -certain amount of flotation at all times of tide. After the gates had -been in use many years it was found that one of the wheels had been -detached for some time, but the buoyancy of the gate had prevented any -mischief resulting. The buoyancy of the lower part of the gate is -somewhat analogous to that of the air-chamber which Mr. Brunel -introduced afterwards in his wrought-iron dock gates. - - -_Bristol Docks._ - -About the year 1804 that portion of the river Avon which flows in a -serpentine course through the city of Bristol was enclosed, and the -water in it retained at a constant level, a new cut or shorter channel -being made for the river. The portion separated, called the Floating -Harbour, or Float, is about two miles long and 100 yards broad. At its -lower end it is connected with the river by the Cumberland Basin, a -half-tide basin, with two locks, and at its upper end by a feeder, which -brings the water of the Avon into it, the river in dry weather being -stopped from passing into the new cut by the Neetham Dam, About half-way -up, the Float is entered on the north side by the river Frome; and, a -little above this junction, it is crossed by the Prince's Street -drawbridge, which divides it into two parts. About 170 feet above the -bridge the Float is connected with the new cut by another basin with a -lock, called Bathurst Basin. - -Mud and other deposits had accumulated to such an extent in the -Floating Harbour, that at the end of the year 1832 the directors of the -Dock Company employed Mr. Brunel to suggest remedial measures. - -In order to effect his object at the least possible cost, he proposed -certain works, together with an improved system of managing the water of -the river, so as to allow more of it to pass through the Floating -Harbour, by means of which great benefit might fairly be -anticipated.[178] He remarked that,-- - - By systematically following this course, the object of which is - simply to keep in continual action all the means, however small, - which can at the moment be brought to bear, and thus day by day to - remove or neutralise, or merely diminish (as the case may be), the - continual deposit which is going on--in fact, by applying a - constantly acting remedy to oppose a constantly acting evil--I have - little doubt that the formation of shoals similar to the existing - ones may be entirely prevented, or at all events that they will be - of such a nature as to be easily removed by two or three yearly - scourings, and without that time and labour which are now expended - with so little effect. - -It should be observed that the yearly scourings, which became so -objectionable to the trade, were not introduced by Mr. Brunel, but were -part of the original arrangements of the docks. - -After the reception of Mr. Brunel's report, the Dock Company executed -the works which he required, namely, the Sluice, Trunk, and Drag-Boat; -but his other recommendations, as to scouring and increased supply of -water, were only acted upon to a limited extent. - - * * * * * - -In 1842 the Directors again asked Mr. Brunel to report, in conjunction -with Captain Claxton, upon 'what further measures are requisite for -keeping the Floating Harbour more clear of mud than it has been for a -few years.' - -Mr. Brunel thereupon made a report to the Directors. After having -referred to his previous reports of 1833 and 1834, he remarked that 'the -efficiency of the whole system then recommended and adopted, and -subsequently partially carried out, depended entirely and was founded on -the supposition of the then existing mud-banks and shoals being first -removed, and the Float deepened at once to the full extent required,' -according to the plans which he had pointed out; and that 'the -increasing the supply of water through the Float was one of those means -on which he had most insisted' as necessary for keeping it clean and -preventing its becoming a settling reservoir. He then continued,-- - - The sluice at Prince's Street Bridge, the trunk--or syphon, as it - was originally, and perhaps more correctly, called--at the - underfalls, and the drag-boat have alone been brought into - operation. These were originally intended as mere aids, which, in - conjunction with _the increased supply of water_, were expected, - after the complete deepening of the Float, to be sufficient, with - _two or three yearly scourings_, to keep it to the required depth: - these were (perhaps unfortunately) found so effective as to induce - a hope that they might be depended upon solely for the removal of - the evil. The permanent interests of the port were, I cannot but - think, sacrificed to temporary convenience: the scourings which - were required as a preliminary step to restore the Float to its - original state, or to that which was said to have been its former - state, and which is now required, were indefinitely postponed. - - A material improvement being notwithstanding soon perceptible from - the first effects of the drag-boat and the removal of mud through - the trunk, the periodical scourings which formed part of the system - approved of for adoption were in a great measure given up to the - objections of the traders. The precautions actually necessary - against admitting into the Float the tide water of the Avon, - heavily charged with mud, were gradually sacrificed for the same - reasons. From all these and many other, but very similar, - circumstances no further progress has been made since the first - improvement, which was felt to be, and which unquestionably was at - the time, very considerable. For until this period it had been the - general practice to lighten all deeply laden vessels at the - entrance of the Float; and, notwithstanding this precaution, it - must be in the recollection of everybody that it was a common sight - to see several large vessels aground at various shoals in the - Float, and unable, without further discharging the cargoes, and - without great consumption of time, labour, and ropes, to get up to - the quays. For several years past the grounding of the deepest - vessels has been the exception, not the rule, but during all this - period it has been one continued and almost vain attempt to - struggle against the old difficulties with insufficient means. - - * * * * * - - For the removal of such deposits as will still be formed, I propose - two means; and first as regards those deposits which are - continually going on. These are formed almost entirely of mud, - which, from its want of consistency when first deposited, the great - quantity and the large surface over which it extends, as well as - the great depth of water, cannot, as I have frequently explained, - be easily or economically removed by the ordinary process of - dredging: for this reason I originally proposed the drag-boat in - conjunction with the trunk at the underfalls, and which has, so far - as it has been applied, completely answered my expectations. - - I should now propose a similar arrangement for the upper float. - - * * * * * - - I should propose to make the additional drag-boat thus required of - rather greater power than that now in use, and to construct it so - that a chain of dredging-buckets could be hereafter attached to the - shaft; and, secondly, for the purposes of deepening the hard bottom - of the float, and of removing those banks of hard materials which - have either always existed, or have been allowed to accumulate, - dredging must be resorted to. But I should be disposed to attempt - hand dredging or spooning in the first instance; for, although the - depth of water is great, I believe the work could be executed as - cheaply, or nearly so, as by the steam dredging, as the original - outlay of capital would of course be much less, while the facility - of working at several points at once, or of moving from one berth - to another as the convenience of the trade would best allow, would - be much greater; the operation also would be much more under - command, which, taking into consideration the possibility of - undermining the foundations of the quay walls or buildings, is not - an unimportant advantage. - - When the required depths are once obtained, the natural deposits - even of the harder description may probably be easily removed by - the drag-boat or by the occasional use of hand dredging. - -The recommendations contained in this report were not adopted. - -In 1839 Mr. Brunel, in a report to a Committee of the Council of the -City of Bristol, suggested several improvements connected with the Port, -almost all of which have since been undertaken. He proposed to -straighten and widen the course of the river, and to make new locks, -both from the river to Cumberland Basin and from that basin to the -Floating Harbour, or, as an alternative, to construct docks at Sea -Mills, a creek on the Avon, about two miles below Bristol. - -He also proposed to construct a large pier at Portishead. The rise of -tide is there sometimes 45 feet, and the velocity of rise or fall as -much as 10 feet per hour. There is also a great deposit of mud by the -Severn. Mr. Brunel considered that these circumstances rendered a fixed -structure undesirable, and he therefore recommended a floating pier. He -said:-- - - I propose two or three vessels of 300 or 200 feet of length, built - of iron, as the material cheapest and best adapted to the purpose, - of 16-feet or 20-feet draft of water, and about 30 feet beam, - moored close stem and stern, so as to form one continuous floating - body. Any steamboat or other vessel alongside will of course be on - the same level as the pier; the passengers, on disembarking, will - at once be on a level platform or deck, under shelter, where the - luggage or goods can also be placed; and the communication with the - shore will be effected without steps.... Such a pier would afford - stowage for almost any quantity of coals, fresh water, and general - goods, which could be stored here for embarkation. - -In 1847, after an Act had been obtained for making a railway from -Bristol to Portishead, with a pier at the latter place, Mr. Brunel -designed the pier on the plan described in his report of 1839; but the -project was not carried out. - - * * * * * - -As has been already mentioned, the communication between the lower part -of the Floating Harbour and the river Avon is through the Cumberland -Basin; between this basin and the river were two locks, made at the time -that the Floating Harbour was constructed. - -Owing to the increased size of merchant vessels, it had long been in -contemplation to enlarge the entrance. At the time when the 'Great -Britain' was built, the northern lock was so narrow that a portion of -the upper masonry had to be removed in order to give room for the ship -to pass from the basin to the river on a spring tide. It was then felt -that the enlargement of one of the locks could no longer be delayed, and -Mr. Brunel was asked to adapt the narrower or southern entrance lock to -the passage of the largest vessels. - -Between the two locks was a pier, from which vessels were guided, and -the gates opened or shut. The elongation of the lock was limited by the -length of this pier, as it could not be extended towards the river -without diminishing the area of entrance, nor could it be extended -upwards without lessening the area of Cumberland Basin. Mr. Brunel, -although hampered by this restriction, succeeded in obtaining a lock of -considerable length. He constructed the gates of a single leaf, and -placed the upper gate outside the lock so as to shut against the upper -end of the middle pier, and to swing back when opened into a recess in -the side wall of the Cumberland Basin. He thus avoided the necessity of -finding room on the pier for the machinery to open one of the leaves of -the upper gate. Had the gate been in two leaves, the lock would have -been shortened from 30 to 40 feet. At the lower end he placed the gate -as near the river as possible; and, lest the end of the middle pier -should not be strong enough to withstand the pressure, he secured the -quoin stones, against which the gate closed, by horizontal wrought-iron -bars at different levels, built into the side wall of the lock. - -The lock is 262 feet in length between the gates, and 54 feet wide at -the narrowest part. - -The masonry is of plain character, all the part below the ashlar coping -being of ordinary fitted rubble of great thickness, solidly built with -hydraulic lime mortar. The ground behind the wall consisted of a wet -silty clay, causing a great pressure against the masonry. The under part -of the body of the lock is formed to a semi-oval cross, section. - -The works were commenced by the construction of coffer-dams at each end. -In 1846, when the masonry was approaching completion, a very high tide -took place, and a portion of the upper dam gave way. As some work still -remained to be done at the sill and apron of the lower gate, Mr. Brunel -decided to make a brick dam in the middle of the lock, where the masonry -had been completed. This brick dam was a horizontal arch built on the -bottom of the lock, up to the level of the water in the Floating -Harbour. The abutments were formed by the masonry of the lock walls, -which was notched to receive the bricks of the arch rings. The dam was -28 feet high, only 8 feet thick at the bottom, and 3 feet thick at the -top. It was set in Roman cement, and was completely water-tight. It was -easily and rapidly made, and the cost was small, as compared with what -would have been the cost of repairing the upper dam. - -In this lock the chief point of interest consists in its being the first -in which wrought-iron gates were introduced, these gates being at the -same time made buoyant. - -Floating caissons had been previously used at the entrances to graving -docks, and in similar situations; indeed at Bristol, a caisson had long -been employed at Prince's Street Bridge, to separate one part of the -Floating Harbour from the other. The buoyant gates of the Bristol Docks -differ essentially from these vessels, inasmuch as, instead of requiring -to be floated into their places, they turn on a hinge, and do not rise -or fall vertically. - -The gates are provided with wheels, but only a small part of the weight -rests on them, as the gates are rendered buoyant by large air-chambers, -formed in the lower part of them. - -The upper and lower gates are alike in construction and dimensions, so -that it is only necessary to describe one of them. (See woodcut, fig. -18.) - -The extreme length of the gate is 58 feet, and the extreme height 29 -feet. In the middle it is about 10 feet wide, the width diminishing to 3 -feet at the top. In plan it is curved to resist the pressure of the -water. The gate when closed is not at right angles to the direction of -the length of the lock, but is at an angle of about 12 deg.. The length is -thus scarcely increased, while the travel in being opened and shut is -much reduced. The top is at the level of the water in the Floating -Harbour; so that, when the tide falls, the water in the Cumberland Basin -may be retained at the same height as in the Float. - -[Illustration: Fig. 18. Bristol Dock Gate. - -_Elevation._ _Section A. B._ _Section C. D._ - -_Plan._ - -_Scale of feet._] - -The air-chamber is formed by two water-tight decks of wrought-iron -plating, one at the level of half-tide, the other a short distance above -the bottom of the gate. Above the deck forming the top of the -air-chamber, the water, as the tide rises, flows freely into the -interior of the gate, through openings in the face next the dock, so -that when the water is level with the top of the gate, the part above -the air-chamber is full of water, which flows out again if the level of -the water falls. - -In ordinary working the gate only needs to be opened or shut when the -water is above the level of half-tide, and therefore at these times the -whole of the air-chamber is immersed. To whatever height the water rises -above this level, the buoyancy remains almost the same, the only change -being caused by the displacement of the iron of the upper part. This -displacement, when the water is level with the top of the gate, amounts -to about six tons. - -The size of the air-chamber is so arranged that when the water is level -with the top of the gate it is just afloat; and at half-tide, when the -water is at the level of the top of the air-chamber, there is a weight -of about six tons on the wheels.[179] - -The gate is provided with a sluice, by which water may be admitted into -the air-chamber, or allowed to escape when the water outside is at a -lower level; there is also a pump, by which leakage water may be -extracted. The volume of the air-chamber may thus be altered at will, -and the buoyancy may be modified so as to counteract the effect of the -weight of any mud which may be deposited upon the decks of the gate. - -There are in each gate two very large double sluices, which are used for -working the lock, and for lowering the water in the Cumberland Basin to -meet the tide. They are also used for scouring away the mud. The -shutting pieces of the gates, which bear against the granite masonry and -form a water-tight joint, were made of Honduras mahogany, a very durable -wood for the purpose. The timber is bedded in creosoted felt and bolted -to the gates; and the pieces are still sound, after the lapse of more -than twenty years. - -Underneath the gate are two wheels, slightly conical, 3-1/2 feet diameter -and 1 foot wide, which travel on level cast-iron rails let into the -masonry of the gate floor. There is no heel-post such as is usual in -dock gates, but the gate is hinged to the masonry by wrought-iron -collars and a wrought-iron pin about 8 inches diameter, which is passed -through them. Any portion of the weight of the gate which is not -supported by the flotation of the air-chamber is borne entirely by the -wheels, the arrangement at the hinge being merely for the purpose of -retaining the gate in its position and guiding it in opening or -shutting. The gate is moved by chains, which are attached to the barrels -of powerful crabs, and conveyed through passages formed in the masonry; -at the lower ends of these are chain rollers or broad sheaves, round -which the chains pass. The sheaves are fluted on the circumference, to -ensure their turning readily. When the gates are nearly afloat, they can -be moved with great ease; but at the time of their construction it was -considered essential to provide machinery sufficiently powerful to open -and close them at low water, when the whole weight of each gate, nearly -one hundred tons, rests on the wheels. The crabs and chains were -therefore made much stronger, and were more difficult to move, than if -they had been merely designed to work the gate under ordinary -conditions. - - * * * * * - -The gates were constructed in Bristol at the Great Western Steamship -Works in 1847. After the lower gate had been tested and proved to be -water-tight, it was launched, and floated with the front surface nearly -level. The positions it would assume under different conditions had been -calculated beforehand. Before it was fixed, the gate was made to float -nearly upright by the admission of water; it was then towed to its -place, and brought into correct position. The hinge-pin was dropped -through the collars, and by admitting water into it, the gate was sunk, -so that it rested upon its wheels. This operation had to be performed -at high water, which only lasted for a short time. - -In fixing the upper gate, the water was kept up to the proper level by -the lower gate, and therefore there was no need to do the work quickly. - - -_Plymouth Great Western Docks._ - -As it was considered probable that, on the completion of railway -communication, mail packets and other large ocean steamers might make -Plymouth their port of departure, a company was formed in 1846 for the -construction of a dock in Mill-bay, a large inlet in Plymouth Sound near -the entrance to the Hamoaze. - -The bay was already protected from the prevailing winds by a pier at its -eastern side constructed by Mr. Rendel. - -It was decided to form a wet dock and graving dock at the inner end of -the bay, and to make quay walls along the side of the outer part, to -join the existing pier. A floating pier for large vessels afterwards -became part of the scheme. In 1847 preliminary trials were made as to -the best means of excavating in deep water the limestone rock of which -part of the bottom of the bay consisted; some quay walls were also -constructed and made use of by the shipping. - -At the end of 1851 a contract was entered into for the execution of the -whole of the works remaining to be completed; the most important of -these were the entrance, the graving dock, and the completion of the -floating basin. - -The progress of the undertaking was much facilitated by Mr. Brunel -giving his sanction to the proposal of the contractors to form a stone -and earth embankment across the mouth of the bay, instead of employing -the usual timber coffer-dams. This embankment, which completely answered -its purpose, was finished by the middle of 1853. - -The works now proceeded steadily until they were completed, and at the -end of the year 1856 the dock was opened. - -The middle of the embankment was cut through, and an entrance channel -dredged to a level of 8 feet below low water. The remainder of the dam, -being partly protected by masonry walling, was used as a quay, and -served for the protection of the outer basin. - -Mr. Brunel had prepared the foundation, and had intended to build a pier -to shelter the entrance gate from the sea, and to assist in pointing -long vessels. The want of this shelter was felt in the gale of October -1857, when the gates were thrown down. In order to avoid any future -casualty, storm gates, or framed struts reaching down to low water -level, were placed immediately behind the entrance gates, so as to -support them against heavy seas. - -The dock, which is of oblong shape, has an area of 13 acres, and a -length of quay wall of 3,490 feet. The greater part has a depth of 22 -feet below high water at spring tides, or 16 feet at neap tides; the -remainder is 4 feet deeper, or the same depth as the channel in the -outer basin. - -The walls are 8-1/2 feet thick at bottom, and 3-1/2 feet at top, and are built -to a curved batter. They reach generally to a depth of 5 feet below low -water, and rest on concrete 12-1/2 feet thick, carried down until a rock -foundation is reached, which in some places is as much as 40 feet below -the bottom of the dock. - -To accommodate the larger paddlewheel steamers, the entrances to the -basin and graving dock were made 80 feet in width. - -The dock is entered through a short passage, the sill being 13 feet -below low water. The masonry of this entrance has curved battering -sides, with a segmental invert. - -The entrance is closed by a pair of wrought-iron buoyant gates, which -meet at an angle of 127 deg.. Each gate is 48 feet long, and weighs -seventy-five tons, the breadth being 8 feet in the middle, curving to 2 -feet at the ends. There are six horizontal decks and four vertical -bulkheads. The depth at the heel-post is 22 feet, and at the -meeting-post 35 feet (see woodcut, fig. 19). - -[Illustration: Fig. 19. Plymouth Dock Gates. - -_Elevation._ _Section A. B._ - -_Plan._ - -_Scale of feet._] - -In each gate is an air-chamber, the top of which is at half-tide level; -and its volume is such that when the gate is wholly immersed there is a -small downward pressure.[180] - -Under each gate, near the meeting-post, is placed a wheel, which -supports part of the weight. This wheel is so arranged that it can be -easily removed for repair. The heel-posts are of cast iron, planed and -ground in place against the polished surface of the granite hollow -quoins so as to form a water-tight joint. - -There are large scouring culverts behind the side walls of the entrance; -but for the purpose of regulating the level of the water in the dock, -and of discharging a large volume of water readily, without having to -overcome the friction of ordinary sluice valve faces, each gate is -furnished with a cylindrical valve, of the following description:-- - -From an opening in the side of the gate next the dock there is a large -curved pipe or sluice-way, which terminates inside the body of the gate, -with a circular horizontal orifice about 5 feet in diameter. The opening -is covered by a short length of vertical pipe of the same diameter, -reaching above high water, the bottom edge making a water-tight joint. -This pipe can be raised or lowered by a screw at the top of the gate. -When raised a short distance it allows the water from the dock to flow -out between the bottom of the movable pipe and the orifice of the -sluice-way into an isolated compartment of the gate, and to escape by an -opening provided in the outer face. The movable pipe is guided by -rollers, and from the construction the pressures on it are balanced. - -The entrance to the graving dock, 80 feet wide, is closed by a pair of -gates of the same dimensions and construction as those of the entrance. -This dock is 380 feet long, 92 feet wide, and has a depth of 28 feet -over the sill. - - * * * * * - -The floating pier was erected in Mill-bay in 1852, to accommodate the -steam-shipping trade. It consists of a pontoon with a bridge leading to -it. - -The pontoon is a large wrought-iron vessel of nearly rectangular -cross-section, 300 feet long, with 40 feet breadth of beam, and a depth -of 17-1/2 feet. It is loaded so as to draw 10 feet of water, and is capable -of storing 4,000 tons of coals. To connect the pontoon with the shore -there is an iron bridge, working upon hinges, in two spans of 125 feet -each. The connection between the two spans was supported on a timber -pier, and was made so as to be movable vertically, and capable of being -adjusted by a crab and counterbalance weights. By means of this -arrangement a uniform gradient over the whole length of the bridge could -be obtained at any time of tide, for the convenience of heavily laden -carts passing to and from the pontoon. - - -_Briton Ferry Docks._ - -In 1846 a company was formed to establish docks in Baglan Bay at Briton -Ferry, near the mouth of the river Neath; but nothing was done until -1851, when the necessary powers were obtained under an Act of -Parliament. From the vicinity of the proposed docks to the South Wales -and Vale of Neath Railways, a large amount of trade was anticipated; and -in 1853 an Act was obtained for the South Wales Mineral Railway, which -was intended to terminate at the docks, and was expected to bring a -large traffic in coals and other minerals. - -The dock works were begun soon afterwards, but the earthwork was not -completed, nor the construction of the gate commenced, until the year -1858. The docks were completed, after Mr. Brunel's death, by Mr. -Brereton, and were formally opened on August 22, 1861. - -They consist of an outer tidal basin of about 7-1/2 acres, and an inner -floating basin of about 11 acres, with a depth of water of 27 feet at -spring tides, and 16 feet at neap tides. The two basins are connected by -a passage or entrance of 50 feet in width, with curved battering walls -and an invert, closed by a gate of a single leaf. An important advantage -of single gates is that the sill and quoins may be in one plane, and -that the troublesome and costly fitting of the hollow quoins is avoided. -The sill was laid 6 feet below what was then the low-water level, as it -was thought that future improvements might reduce the bar at the -entrance of the river Neath to that level. This has already been nearly -accomplished.[181] The total length of the docks is a little over half a -mile, and the average breadth is about 400 feet. They are connected with -the South Wales Railway by branch railways. - -With the exception of the walls dividing the two basins near the -entrance gate, the sides of the dock are not constructed with masonry -quay walls, in the ordinary manner, but are formed in a very inexpensive -manner of slopes pitched with furnace slag, obtained from the copper -smelting works on the Neath river, with jetties at intervals for the -shipping. Besides being suitable for the soft clay in which the dock is -made, this plan is specially adapted for mineral traffic, as the work of -loading or discharging a cargo of minerals can only be properly carried -on at the point where fixed machinery is provided for the purpose. This -machinery may be placed as conveniently on projecting jetties as on a -dock wall. The traffic, which consists mainly of coals and metals, is -accommodated at the jetties, which are furnished with cranes for loading -and unloading the vessels employed in the metal and iron ore trade, and -with tipping-frames, which discharge the coals into the ships. These -cranes and tipping-frames are worked by hydraulic machinery. - -In order to facilitate the entrance of vessels from the river Neath to -the tidal basin, and to protect it from the sea, two pier-heads were -built, one at each side of the basin at the point where it joins the -river. These piers are of timber piling and framework, filled in with -copper slag; the entrance between them is 300 feet wide. They were -constructed after Mr. Brunel's death. - -The gate is a wrought-iron buoyant gate, with five vertical partitions -or bulkheads and six decks. The length is 56 feet; the depth in the -middle is 31 feet 6 inches, and at the sides 26 feet 6 inches. The -breadth in the middle is 9 feet, and is curved to 2-1/2 feet at the ends -(see woodcut, fig. 20). - -[Illustration: Fig. 20. Briton Ferry Dock Gate. - -_Elevation._ _Section A. B._ - -_Plan._ - -_Scale of feet._] - -The air-chamber, which is similar to that of the Plymouth gates, is -placed so that the top is at the level of high-water neap tides, about -half-way up the gate. - -There are two sluices at low-water level, each having an area of 8 -square feet. - -The entrance invert being subject to the influx of sand from the outer -basin, and to the deposit of coal rubbish dropped into the dock, Mr. -Brunel decided in this gate not to use wheels, but to make the hinge -and heel-post strong enough to carry the whole weight of the gate, even -if it were unsupported by the buoyancy of the air-chamber. - -The heel-post is a massive piece of cast iron; the bottom part is bored -out, and into it is fitted a cast-iron cylindrical pin, 1 foot 6 inches -diameter and 7 feet 6 inches long. On this are ground discs of steel, -lubricated with oil, whereon the gate rests and turns. Thus the surfaces -exposed to friction are above the sand or grit at the bottom of the -dock. The lower end of the pin fits into a cast-iron socket fastened to -the masonry, and is prevented from turning round by being made -hexagonal. The sides of the hexagon have sufficient play to enable the -gate to adjust itself, when shut, to the masonry sill, so as to be -water-tight. The top of the heel-post works in a brass bush, 18 inches -diameter and 15 inches broad, enclosed in a massive wrought-iron collar, -which is strongly fastened by anchor chains to the masonry. After the -gate was completed the strength of the hinge was tested by moving the -gate before the water was admitted into the dock. The only resistance to -the motion of the gate is the slight friction at the hinge. - -No coffer-dam was used in the construction of this work, but advantage -was taken of a large bank of slag and earth enclosing a portion of the -site of the dock. This was extended and raised, and a sea dam formed. -The dam was cut through when the works were completed, and a channel -dredged to the depth of 6 feet below low water. - - -_Brentford Dock._ - -In 1855 an Act was obtained for making a dock on the Thames at -Brentford, and a railway to join the Great Western Railway at Southall. -The dock has an area of about 3-1/2 acres. - -The works were begun in July 1856, and were completed, and the dock -opened, three years later. - -The walls are founded in the London clay, which here underlies a bed of -gravel of some thickness; from this there was a considerable influx of -water. - -The chief peculiarity of the dock is the form of construction adopted -for the sides. Piers of brickwork, 10 feet long and 2 feet 3 inches -thick, are placed at right angles to the sides of the dock at intervals -of 26 feet. The backs of these piers are connected by horizontal arches, -carried up with a curved batter. The piers are about 20 feet high, and -arches are turned upon them, which support the front part of the quay, -and meet the horizontal arches at the backs of the piers. Thus the sides -of the dock consist of a series of vaults, arched over at the top, and -also at the back towards the pressure of the earth. - -[Illustration: Fig. 21. Brentford Dock Gate. - -_Elevation._ _Section A. B._ - -_Plan._ - -_Scale of feet._] - -The thickness of the horizontal arches which form the bulk of the wall -is only 3 feet, but these are so strengthened by the piers in front, -that a wall strong enough to resist the pressure of the earth behind it -was obtained by means of a very small quantity of brickwork. - -Along one side of the dock the piers are 31 feet long, in order that -coal barges may lie with part of their length in the vaults between the -piers while their cargo is being put on board. By this arrangement the -barges have their longest dimension at right angles to the side of the -dock, and a much greater number can be accommodated than if each -occupied a space alongside the quay wall. The contents of the coal -trucks are tipped into the barges through sloping shoots. - -The entrance has a clear width of 30 feet, and is closed by a single -wrought-iron buoyant gate, which, like the Bristol gates, is, when shut, -not quite at right angles to the entrance. - -The gate is 33 feet long, 19 feet high, 2 feet 6 inches wide at the -middle, curved to 1 foot 6 inches at the sides, and weighs sixteen and a -half tons. It is divided into compartments by four decks and two -vertical bulkheads. The air-chamber occupies the whole space below one -of the decks, 7 feet 6 inches above the bottom (see woodcut, fig. 21); -and there are two sluices, each having an opening of 4 feet by 2 feet. -This gate, like that at Briton Ferry, has no wheel under it, the weight -being carried upon the pivot. - -In order to avoid side strains upon the pivot and top collar, a -counterbalance arm is fastened on the top of the gate. This is formed of -two cast-iron girders, bolted together and enclosing weights between -them. The ends of these girders project beyond the heel-post over the -quay, as in canal lock gates, and carry the machinery by which the gate -is turned, as there are no crabs, chains, or chain rollers. Instead of -these, a cast-iron circular rack is fixed on the top of the masonry, in -which a pinion works, turned by gearing fixed to the end of the -counterbalance. - -This gate turns with remarkable freedom, and the current of water -running into the dock on a spring tide opens it completely. - - -_Pier at Neyland, Milford Haven._ - -The South Wales Railway was originally intended to terminate at -Fishguard, on the north coast of Pembrokeshire, with the view of -securing a large quantity of Irish traffic, the distance across the -channel to the Irish coast at Wexford being only 60 miles, less than the -distance from Holyhead to Kingstown. - -It was, however, ultimately decided to form a terminus, which would -accommodate the ordinary Irish traffic, and would not require such an -extensive outlay on harbour works as would have been necessary on the -northern coast. - -With this object, the inlet or natural harbour of Milford Haven was -examined, and the South Wales Railway was carried to Neyland Point, -opposite Pembroke, where the position is sheltered, and there is deep -water at all times of tide for the largest vessels. - -The pier at Neyland, or New Milford, which was made in 1857, consists of -a timber viaduct, with a pontoon at the end, 150 feet long and 42 feet -beam, loaded so as to draw about 7 feet. There is a depth of 16 feet -alongside it at low water, and it is connected with the shore by a -landing bridge. The pontoon is made of wrought iron, and has three -transverse and two longitudinal bulkheads. It is moored by chain cables, -which pass through two large hawse pipes, extending from the bottom -nearly up to the deck, with cast-iron mouthpieces at their lower ends. -The cables passing through these are anchored firmly to the ground at a -considerable distance from the pontoon. - -The pontoon was intended to be the centre of several others, which were -to be moored in deeper water. - -The rise of tide being sometimes as much as 25 feet, it was necessary -that the landing bridge should be of considerable length, in order that -there should be a moderate inclination at all times of tide. It is -accordingly made in one span of 205 feet. It consists of two plate-iron -side girders, of the uniform depth throughout of 14 feet, and width of 2 -feet 6 inches. These are placed 12 feet 6 inches apart, the roadway -being between them. The ends of the girders which rest on the pontoon -are provided with cast-iron wheels, 1 foot 6 inches in diameter. - -The pier has since been extended by additional pontoons, which were -those used in the floating of the Saltash Bridge. - - - - -CHAPTER XV. - -_MISCELLANEOUS WORKS._ - - THE GREAT EXHIBITION OF 1851--THE CRYSTAL PALACE WATER TOWERS, - 1853--POLYGONAL RIFLE, 1852--GUNNERY EXPERIMENTS, 1854--FLOATING - GUN-CARRIAGE, 1854--RENKIOI HOSPITAL BUILDINGS, 1855. - - -There are several matters of importance in which Mr. Brunel was engaged, -which could not under any system of classification be introduced into -the preceding chapters; these are therefore collected under one head of -'miscellaneous works.' - -The first of these is his connection with the Great Exhibition of 1851. -He was from the beginning one of the most zealous supporters of this -undertaking, and was appointed a member of the Committee of the Section -of Machinery, whose duty it was to classify the objects to be exhibited -in that department. - -Upon the question of awarding prizes to exhibitors, Mr. Brunel held a -very decided opinion adverse to the plan ultimately adopted. In a letter -to the Chairman of the Committee, dated March 11, 1850, he writes:-- - - I am sorry to say that I am obliged to leave town to-night. - - We are summoned to-morrow, it appears, on the subject of prizes. - Not being a member of the Commission, I have perhaps no right to - express an opinion upon a principle which seems to have been - adopted--that of giving prizes--but as applied to machinery I - suppose I may. I strongly disapprove of any prizes being offered in - our section. - - 1. I believe it is quite unnecessary. - - 2. I believe it will be impossible to define beforehand the - subjects for which any limited number and amount of prizes are to - be promised, the subjects are so indefinitely numerous; and like - the building, however large it may be made, will not be large - enough to hold all that is sent, so as regards the prizes, however - numerous the subjects, they may very likely not embrace the very - things which turn out to be most deserving. - - 3. I believe it will be impossible to distribute any limited number - of prizes with justice, and quite impossible to satisfy the public. - - Two machines for the same purpose may be remarkable--one for its - ingenuity and beauty of workmanship, but of doubtful practical - economy in application; the other clumsy, and not well made, but - apparently likely to have the germs of much good--there are - thousands, or rather an infinity, of shades of degrees and - qualities of merit. - - And lastly, I believe the prizes will be mischievous, as conferring - undue advantages in many cases upon a thing well displayed, and - well got up, and will be sought for and obtained for puffing - purposes. The opportunity of exhibition I believe will be quite - sufficient to induce all the competition we can desire. - - I think money prizes quite a mistake, and medals or distinctions - pretty nearly as bad. I hope you hold the same views, but I send - you mine. - -Mr. Brunel's views found no favour at the time; but subsequent -experience has convinced those best able to form a sound judgment in the -matter, that 'no prizes of any kind should be awarded' in International -Exhibitions.[182] - -Mr. Brunel was also a Member of the Building Committee; and he accepted -the office of Chairman and Reporter of the Jury for Class VII., on Civil -Engineering, Architecture, and Building Contrivances. - -He took a very active part in the proceedings of the Building Committee. -Designs were invited, and two hundred and forty-five were sent in. None -of these were considered satisfactory by the Committee, and they -submitted to the Royal Commission a design of their own, the principal -feature of which was a dome 200 feet in diameter. - -Mr. Brunel was responsible as a member of the Committee for the plans -prepared by them, and as regards the dome may be said to have designed -it himself, but he expressed strong objections to the substantial and -expensive buildings which it was proposed to erect in brickwork. His -idea was that the building should be in what he called the 'railway shed -style;' and he wished to produce effect rather by the construction of -the roofs, &c., than by any architectural elevation. - -When, therefore, the plans of the Building Committee failed to meet with -public approval, and the late Sir Joseph Paxton submitted his well-known -design, Mr. Brunel gave it his cordial support, and defended it against -its detractors. He thus spoke of it in the report of the Jury of Class -VII. - - As regards Mr. Paxton's claim, amid the competition of the whole of - Europe, he proposed that mode and form of construction of building - which appeared on first sight, and has since proved to be, the best - adapted in every respect for the purpose for which it was intended. - The design possessed this merit of fitness for its object in a - singular manner. There was no startling novelty in any one point - which could lead astray the judgment of those who had to determine - upon the choice of plan, or which could in the first instance - obtain, still less permanently secure, the good opinion of the - public. As regards the form of outline, which is most simple, - several designs nearly resembling it had been submitted in the - general competition. As to the material, several proposals had been - previously made to cover the whole area to be enclosed with glass, - and iron would of necessity be employed for the framing; but in the - combination of form and materials, in the particular mode of - applying those materials, and in the adaptation of the forms to be - selected to their convenient use, as well as in the various details - by which the whole was rendered perfect, the design was entirely - distinct in character from all that had been proposed, and appeared - at once to have the one single merit of being exactly that which - was required for the purposes in view. The design as realised has - completely fulfilled every condition of utility. - -The award of Council Medals (the highest prize given) was recommended -to Sir Joseph Paxton, and to the contractors, Messrs. Fox, Henderson and -Co. - -In a later part of the report, in announcing the recommendation of a -Council Medal to His Royal Highness Prince Albert, for the model -dwelling houses which were erected near the Exhibition building, and -exhibited by the Prince, Mr. Brunel spoke in emphatic language of the -magnitude and importance of the results which would follow from the -introduction of improved dwellings for the working classes.[183] - - * * * * * - -When the Crystal Palace Company was formed in order to purchase the -Exhibition building and erect it, with additions, at Sydenham, Mr. -Brunel took a great interest in the project, and frequently went down to -examine the progress of the building and gardens, and the beautiful -architectural courts which were to be the chief attraction in the -interior of the Palace. The water towers, which are so conspicuous a -feature in the building, were designed by him. - -The towers are 284 feet high, and carry near the top tanks 47 feet in -diameter and 38 feet high, holding 1,200 tons of water. - -The foundations required great care in their construction. The tanks had -to be placed at a height of more than 200 feet, and the towers, which, -with their load, weighed fully 3,000 tons each, had to rest on the -sloping side of a clay hill. There was also the possibility that by the -bursting of a pipe a large quantity of water might be suddenly -discharged, and so cause a slip in the surrounding ground. Mr. Brunel -carried the foundations down to a considerable depth, forming a large -base of Portland cement concrete, and placing on it a cone of brickwork -in cement, rising up to the ground level. The towers are twelve-sided, -with two hollow cast-iron columns at each angle. The height of the -building below the tanks is divided into ten stories, and at each floor -there is a strong wrought-iron diaphragm, or shelf, 5 feet wide. The -columns are also connected by strong diagonal bracing in the sides of -the tower. - -The tanks are made of wrought iron, and the water pipes are placed in -the interior of the tower. Mr. Brunel did not think it would be prudent -to form any of the columns of the towers into pipes, lest the expansion -due to the temperature of the water should cause unequal support to be -given to the tanks. - -In July 1855, the pipes were proved, and the towers were completed -shortly afterwards. - - * * * * * - -The remainder of this chapter will relate to matters which have but -little in common with the subjects of the earlier part of it; but the -change is hardly less marked than that which took place in the nature of -the questions which occupied public attention within a few years of the -close of the Great Exhibition. - - -_Polygonal Rifle._ - -In October 1852, Mr. Brunel consulted Mr. Westley Richards, of -Birmingham, as to the manufacture of a rifle 'for the purpose of -determining whether there was anything in a crotchet he had upon the -subject.' The rifle was made by Mr. Westley Richards according to Mr. -Brunel's directions, and finished in May 1854. Many experiments were -tried with it, at Birmingham and at Manchester, in the spring of 1855, -and afterwards at Woolwich; and its performances obtained great -notoriety. - -The history of this rifle, and the objects Mr. Brunel had in view in its -design, will be understood from the following letters to Mr. Westley -Richards:-- - -I. - - - October 25, 1852. - - I have long wanted to try an experiment with a rifle, for the - purpose of determining whether there is anything in a crotchet I - have upon the subject, but I have been deterred from attempting it - from the feeling that in these abominable patenting days (I hate - patents) the chances were, that if, in the progress of my - experiments, any new result, good or bad, were observed, or a - workman should think he _saw_ something, a patent would be taken - over my head, and, to say the least, I should be stopped in - pursuing my own investigation, as has happened to me more than - once. - - I have also been deterred by my not knowing whether the existing - machinery for rifling barrels would enable me to obtain an - increasing or varying twist from one end of the barrel to the - other, as this would be necessary to make the experiment, and I - should not care to incur the expense of a machine on purpose. My - introduction to you, through our mutual friend Whateley, induces me - to make the enquiry whether your apparatus or mode of rifling - enables you to give such a twist, and if so, whether you could and - would make me a barrel. If so, I will trouble you with an - explanation of my scheme, as I should have no secrets with you. - - II. - - February 7, 1853. - - I take this opportunity of mentioning again the subject I once - wrote or spoke to you about. I want a rifle barrel made octagon - shaped inside, the octagon having a twist rather more than usual, - and an increasing twist, say twice as much at the mouth of the - piece as at the breech. Can you make me such a barrel for an - experiment? I will explain to you the object when we meet, as it - can only be done _viva voce_. - - III. - - [The following letter was written to Mr. Westley Richards in answer - to a request that Mr. Brunel would permit him to obtain a license - from Mr. (now Sir Joseph) Whitworth to make rifles of a polygonal - shape. Mr. Whitworth had obtained a patent for improvements in - cannons, guns, and fire-arms, in February 1855, and in his complete - specification, dated May 30, 1855, he had for the first time - claimed-- - - Firstly, the several combinations of parts forming, when put - together, the barrels of ordnance, or fire-arms, having a polygonal - spiral shape. Secondly, the use of the spirally-shaped segments. - Thirdly, the adoption of the polygonal spiral for rifled ordnance - and fire-arms. Fourthly, the combination of parts forming the - breech-loading apparatus.] - - November 26, 1858. - - I am obliged to you for your communication on the subject of the - octagon gun, and in acknowledging your courtesy and gentlemanly - feeling I would add that it is only what I always felt I could rely - upon from you. - - I beg you will not hesitate to take out a license from Mr. - Whitworth for octagon guns (if, as a matter of business, you think - it convenient to do so) on account of any prior claim which you may - know I could set up, and if you get a license for a nominal - consideration, as I understand you can, of course as a man of - business you should do so. I have no intention of interfering with - Mr. Whitworth's patent, even to indulge the feeling I have against - all patents and protective laws, which I consider have become the - curse of the day, and the sources of the greatest injury to - inventors and manufacturers, and still more to the public; and I - should also be very sorry even to annoy my friend Mr. Whitworth - merely for the sake of showing that I had previously made the gun - (at least you made it for me), and I believe others have preceded - me, which he has patented; and I assure you that I shall not - consider your taking out a license as in any way a denial of this - fact, of which you are cognisant. - - I have never seen Whitworth's patent; what is it exactly that he - does patent? It cannot be merely the polygon, because, even if - nobody had preceded me, that would have been already a copy of - mine, which not only was made before he began his investigation, - but was lent by me, at your request, to him, I think before his - patent. My rifle is, I am told, doing quite wonders at Woolwich, - and I begin to think there must be something in the principle which - I intended to introduce into it, and which is totally different - from what I understood to be Whitworth's. I sought to use a - comparatively loose ball, but which I thought would centre itself, - both in position and direction, to the axis of the barrel by the - peculiar action of a polygon within a polygon acted upon by an - increasing pitch, and it really seems from the results as if my - theory was correct.[184] - - -_Gunnery Experiments._ - -In 1854 Mr. Brunel took up warmly the question of improvement in large -guns, which was then attracting the attention of several scientific men. - -The friendship which had for some years previously existed between him -and Mr. (now Sir William) Armstrong, of Newcastle-on-Tyne, gave Mr. -Brunel opportunities for discussing these matters, with a view to their -being carried into practical effect. - -The following extracts from a letter written by Mr. Brunel, in April -1855, to Mr. James Nasmyth, explain generally his opinions at that time -upon the construction of large guns:-- - - From what I have observed of the operation of fractures under - _sudden_, quick-acting forces--such as bursting of guns, and - fractures under blows, as in our railway smashes--I have arrived - deliberately by observation at the conclusion, which every - mechanical-minded man arrives at more or less by intuition, that - homogeneity and equality of tension and of elasticity in the parts - are necessary for strength to resist a violent strain applied - suddenly in its full force, which I will call a blow. My - impression, from the result of observation, is, that this operates - much more than is generally assumed. - - If you suppose a bar, say an axle of uniform section and uniform - quality in every respect, it will bear bending into extraordinary - forms even by a blow; and if you assume that portions of it become - more tenacious and stronger, but remain equally elastic, the - ultimate strength of this bar will not, I think, be materially - increased or diminished; but if you suppose the elasticity of these - portions either increased or diminished, I believe the ultimate - strength of the bar under a blow is diminished. In like manner, I - imagine that in the section of a gun barrel, if portions are more - or less elastic than others, or at all different in their - character, not only many points of fracture may be determined on, - but that the whole may be rendered much less able to resist the - violent explosion. The strain produced by the explosion and the - plane of fracture is almost certain to be in a plane passing - through the longitudinal axis, and therefore I had assumed that one - would avoid as much as possible having any variation of quality - which fagotting must produce to some extent in planes in this - direction. To attain this end, I had endeavoured to scheme some way - of welding up 'cheeses' or discs, which might be hammered up - splendidly homogeneous of the full diameter and of a considerable - thickness, and I wish that you would scheme the best way of welding - them together. I should suppose that the centre surface might be - welded, and wedges welded in all round, or some other mode devised, - bearing in mind that the strain in any plane transverse to the axis - is small, only that arising from the recoil of the breech and the - friction of the shot. - - I have also an impression that something harder than ordinary - wrought iron is wanted for the inner surface to resist the - explosion. This you might give probably in fagotting up. I am - trying the effect--as much for the amusement of the thing as with - any great expectation--of a cylinder of hardish material wrapped - round with iron wire, laid on with a certain amount of tension - proportioned to the diameter. Such a barrel ought to be - strong--whether practically successful is another thing. - -The scheme of making a gun with the barrel wrapped round with wire, -which is referred to in this letter, was one which Mr. Brunel and Mr. -Armstrong were very desirous of making the subject of actual experiment. -Whether or not it would under their hands have become practically -successful, could not be ascertained, as they were obliged to abandon -the project, in consequence of the wire covering being patented, in May -1855, by Mr. Longridge. - -The following letter to Mr. Armstrong relates to the same subject, and -is interesting not only as showing Mr. Brunel's correct appreciation of -a principle which is the essence of the coil system of constructing -guns, but as further illustrating his objections to the patent laws:-- - - - June 8, 1855. - - Have you ever done anything towards my experiment of the wire gun? - I have been anxious for some time past to learn about it, but have - waited to see you; to-day I learn that Longridge is taking out a - patent for it. I daresay it is his own idea, and I only regret it, - as I suppose it will now prevent my pursuing it; and I think it - likely that with your assistance we should have succeeded in making - at least as good a gun as he will. The principle I am disposed to - think good; the success would depend upon the practical - application, and but for these patents, the more competitors the - better for the public. As it is, competition is destroyed. Let me - know if you had done anything. Pray let me know also what you are - doing about your own, in which I feel equally interested. - -Mr. Brunel had also considered the advantages of making the bore of the -gun polygonal, with a projectile shaped to fit it. He had a portion of -cannon tube and a projectile made by Mr. Armstrong in the beginning of -1855, but he did not himself pursue the question further. - -Indeed, after the middle of the year 1856, when the works of the 'Great -Eastern' steam-ship began to occupy a large portion of his time, Mr. -Brunel was unable any longer to take part in gunnery investigations; but -he watched with unabated interest the proceedings of those friends who -have continued their experiments, with the great practical success of -which he lived to see only the beginning. - - -_Floating Gun-Carriage._ - -The plan of a gun-boat, or, as it would be more correctly called, a -floating gun-carriage, which Mr. Brunel designed for an attack on -Cronstadt and other Baltic forts during the Russian war, is clearly -described in the following memorandum, which he drew up for the -information of the Admiralty:-- - - - December 20, 1855. - - The principle is simply the fixing a very heavy gun in a floating - shot-proof chamber or casemate, exposing the smallest possible - surface; that surface to be of such a form as to be struck by shot - only at a very oblique angle; and the gun being a fixture, with the - means only of elevating and depressing to an extent of 10 or 12 - degrees, but with no lateral motion, the port or embrasure need be - only of the size of the muzzle of the gun, so that the gun, the men - working the gun, and everything on board will be perfectly - protected. - - The gun will be directed by elevating the breech, and by slewing - the vessel slightly and slowly backwards and forwards across the - line of aim, by means afterwards explained. - - The men loading the gun will simply load as quickly as they can, - and when the gun is loaded push out a trigger. - - The governor or person directing the gun will stand behind the hood - or chamber, looking direct at the object through a telescope of low - power, fixed horizontally in the axis of the vessel, and made to - move vertically parallel with the axis of the gun, and mounted with - reflectors; so that both telescope and man are completely under - cover, and he, keeping the vessel truly in range and the elevation - correct, will only touch the trigger whenever his line of sight - crosses the object. - - The vessel will carry a small engine, of power sufficient to drive - it for a short time at a good speed, say eight or nine knots, and - at other times to keep up a small forward motion to counteract the - recoil, and to keep the vessel's head moving a few degrees right - and left across the line of range. - - A sufficient portion of the vessel to contain and to float the gun, - ammunition, and engine, will be shot-proof. - - A fore-body and after-body, the top of which will be _a - fleur-d'eau_, or a few inches under water, will be added, to give - such a form of entrance and run as will admit of the vessel - attaining the speed mentioned; but these parts will be mere shells, - and may be full of water, and if damaged by shot will not affect - the buoyancy of the float, besides which, not being above the - surface of the water, they cannot be much exposed to injury. - - The mode of propelling may be by a screw, but I prefer the 'jet,' - which, whether an economical mode of propelling or not, is a - sufficiently good one for this purpose, and exposes _nothing_ - whatever to be injured by shot.[185] - - Whether propelled by jet or not, I should have two small lateral - jets for directing the vessel, such jets being governed by two - cocks handled by the gunner. - - Such a mode of directing the aim by a man under cover looking - through a telescope, with one hand directing the gun and the other - on the trigger, will admit of an almost unlimited degree of - accuracy. - - The gun being in a perfectly shot-proof casemate, machinery may be - adapted to expedite the loading of the gun; and it is not difficult - to make a mechanical arrangement by which the shot and cartridge - shall be lifted up to the gun, inserted, and rammed home, at a rate - far exceeding anything that can now be done by hand; and as the - weight and clumsiness of the gun, the carriage, and machinery are - of no object, I think I can make a breech-loading gun capable of - carrying 12-inch solid shot with a full charge, which may be loaded - and discharged at the rate of two or three per minute; but the - principle of mounting a gun in such a float is equally applicable - to a common gun, which might still be loaded mechanically. - - A few loopholes may be provided through which a fire could be kept - up from a couple of heavy swivel rifles, carrying, say 6-oz. shot, - which would pierce any mantelets or other cover likely next year to - be provided against ordinary rifles. - - A battery, say of twelve such guns, should probably have also two, - or perhaps three, shot-proof vessels of about the same size without - guns, but pierced with a longitudinal fin or ridge, like a wall, - standing, say 10 feet above the water, and 50 or 60 feet long, - strong enough to stand the direct blow of heavy shot at long range, - or the oblique blow of the same shot at short range, and which - could be placed as screens or traverses to cover the flanks of the - battery against distant shot. Against vertical fire I cannot - suggest any defence: the point of attack must be selected to avoid - it. - - The covering vessels may be provided also with loop-holes for heavy - swivels. - - There should also be two or three small and comparatively light, - but shot-proof vessels, to run in and bring out a disabled - gun-boat. - - These last-named auxiliary unarmed boats form an essential part of - the system. - - In all probability the enemy have by this time thrown stones and - other obstacles, and placed infernal machines round the detached - fort, to impede a close approach. They cannot, however, have - covered a very large surface, so that, with some previous sounding, - an approach may be found and a position taken up. - - The auxiliary boats should therefore have strong bottoms under the - engine-room, and the rest of the body be so subdivided into - compartments that they would be proof against serious damage from - rocks and infernal machines, and be able to run in under fire and - ascertain if obstructions exist, and find the channel if they do. - - A battery of such guns could be placed at various points out of - range, say at 3,000 yards, at which distance they would hardly - attract attention by daylight, and would not be visible in the - twilight of night, and could then be concentrated in a few minutes - at the point selected for attack within safe breeching distance, - say 250 yards; and, if twenty-four shot per minute, of 200 lbs. to - 250 lbs. each, thrown with a full charge at 250 yards, can be - directed against a small surface of any stone wall yet built (which - is pierced with embrasures), the effect ought to be great and - rapid. I believe, moreover, that the means of directing the aim - will be so effective that if the embrasures can be seen a shell or - shot may always be sent in with certainty at 250 yards, and the - enemy's guns dismounted. - - Such vessels can rapidly change their position, retreat or advance, - be replaced by fresh ones, or withdrawn altogether. - - The means of transport of such vessels to the seat of war, although - a secondary consideration, has been considered. - - They might easily be placed in an outer shell of iron of a good - form, which could be rigged complete, and so constructed as to give - up its burden when arrived in the seas where it is to act--in fact, - a ship of the class of small screw colliers, made to open at the - bows and its contents floated out ready for action; but the - gun-boat itself, when lightened of ammunition, and the gun lowered - to the bottom as ballast, and fitted up with bulwarks, and a light - movable iron chamber, forming a water-tight forecastle-deck - reaching back, say 30 feet, and schooner-rigged, will, I undertake - to say, make a very fair sea boat. Probably no compasses could be - 'corrected' to be trusted to in such a mass of iron, but a compass - fixed to the mizenmast, say at 30 feet from the deck, would be all - that could be required. - - Immediately abaft the hood or gun-chamber there would be a space - under cover from shot where a companion and skylight could be - fitted up when at sea, and through which light and air could be - obtained at all times when fitted for service. - - The funnel, if ever used when the vessel is not in action, would be - removed for fighting, and the steam and smoke ejected through an - oblique aperture right aft. - - The only point to be determined by experiment is whether a moderate - thickness of iron of the best quality will stand heavy shot at - short range striking very obliquely, say at the worst at an angle - of 30 degrees. - - By the form of the proposed vessel, however, when placed in - position at 250 yards of any of the Cronstadt forts, it could not - be struck at 30 degrees, and probably 99 out of 100 shots that hit - would graze at an angle of 10 to 20 degrees. - - A small part only round the port, or what may be more correctly - termed the muzzle-hole, could be struck with a direct blow. - - There is every reason to believe that slabs of iron of good quality - of 4 inches thick would stand against such grazing, provided they - are put together without being weakened by holes and with some - other precautions, and that sound forgings of 10 or 12 inches - thick, if of sufficient weight in a single piece, would stand the - direct blow. I do not believe that less than this would be safe - against 68-lb., or, as we must expect to meet with, 120-lb. shot at - short range, even when struck obliquely, and this thickness can be - applied without requiring, with the gun ammunition, &c., more than - 6 feet 9 inches, say 7 feet draught of water. - - Another inch of thickness would require another foot of draught; - but if it has been ascertained that the charts are correct, there - would appear to be 10 to 15 feet of water close up to the principal - detached forts, and it would be an immense advantage to take 9 feet - draught of water, and have an unquestionably invulnerable skin. - - If it were considered desirable to construct such a battery, it is - now barely possible to do it in time for the coming season; but if - possible, it could only be rendered so by ascertaining exactly the - dimension and form of iron that each of the large makers could turn - out with their present tools, and according to their present - experience and habits, and to design the details to suit their - existing means, sacrificing probably much that would render the - result more perfect for the sake of rendering it possible to obtain - anything in time. No doubt promises and even contracts could easily - be obtained for making anything in any given time, and zealous and - honest efforts afterwards made to effect what had been undertaken; - but if the slightest attempt is made that involves new tools or new - practices, promises and contracts will not effect impossibilities, - and the probability is that the short time still available will be - lost. - - While all the preparations shall be made on the assumption that the - result is attainable and will be successful, trials must be made, - without loss of time, on the several points to be determined--as to - the resistance of the iron, &c. If they fail, the expense incurred - up to that time in preparing for the whole work will not have been - great. If they succeed, it is just possible that by great exertions - but, above all, by judicious and methodical plans of proceeding, a - complete battery might be launched ready for service in five - months. - - Lastly, I should observe that although the main feature of the plan - is the resisting the effects of the enemy's shot by always exposing - an oblique surface, yet the chances of fatal damage would be small - if such vessels were to run the gauntlet, at night, through the - deep channel, and get into the waters east of Cronstadt. Or if this - is very desirable, as I should think it must be, nothing is easier - than to lift the whole flotilla over the shoal water and launch - them into the deep water beyond. - -Mr. Brunel had matured these plans in September 1854, and they were then -brought under the notice of the Admiralty; but no steps were taken to -test the practicability of the scheme. - -He was, however, induced to make a further representation to the -Admiralty in the following July. He wrote,-- - - Having endeavoured ineffectually several times at the commencement - of the war to impress upon members of the Government the great - advantages that might be derived from the use of iron floating - batteries or gun-boats, if properly constructed, I made another - effort at the close of the last year's campaign, but early enough - to have allowed of the construction of what I proposed before the - opening of the Baltic in the present year, and caused my plans to - be submitted to the Admiralty through a friend. They were not - approved, and I should judge from the answer I received that they - were not understood, and I was never applied to for an explanation. - I had no object in view but the public good, and I therefore kept - the idea, such as it was, unpublished, believing the principle to - be sound and good, and that the day would come when it might be - usefully applied, and the more usefully to this country if not - previously publicly discussed. - - I have no other object to serve now; but after the clear proof that - I was correct in the opinion I shared with so many other persons of - the entire inability of any of the present floating ships, boats, - or war engines to cope with any moderately constructed and - well-armed land battery, I think it right once more, and this time - more formally, to urge upon Government the consideration of the - construction of armaments mechanically constructed and properly - fitted for the special object. I beg to say that I do not mean a - consideration in the ordinary mode, by the able and practical, but - still executive officers of departments, whether engineers or - ship-builders, because I believe that I must be myself, from my - practical experience in this particular branch, at least as - competent, if not more so, to judge in questions of mechanical - construction, whether it be the forging or casting of a gun of - large dimensions, or the construction of a vessel fit for - navigation and capable of resisting shot, or the best mode of - propelling such a vessel--on all which branches I have had much and - tolerably successful practice; but I ask on public grounds for the - deliberate consideration by men of judgment and experience in the - military branch of the subject, such as the attack upon a fortified - place, of which I cannot pretend to be a competent judge, and by - men in a position to be able to express freely their independent - opinions of the advantages that might be attained by the principle - I propose, if capable of being successfully carried out. - -Although the want of efficient gun-boats was then severely felt, this -letter appears to have produced no effect upon the Board of Admiralty. -But the friend who had originally brought the matter under the notice of -the Board took the bold step of writing to Lord Palmerston, and -acquainting him with what had passed. - -Lord Palmerston at once saw the importance of investigating the subject, -and sent for Mr. Brunel, who explained the plans to him. Lord Palmerston -then asked him to see the officials at the Admiralty. Mr. Brunel did so; -but great delay followed. It was, however, unimportant, as hostilities -soon afterwards terminated, and there was no further need of gun-boats, -good or bad. - -This project did not exist only in the outline in which it is described -in the memorandum given above. Mr. Brunel had worked out all the -calculations of displacement, &c., and had made designs and models for -the boat and its various appliances, and had been for some months in -constant communication with Mr. W. G. Armstrong upon the form and -construction of the gun. - - * * * * * - -This will be a fitting place to mention that in 1855 Captain Cowper -Coles, C.B., showed Mr. Brunel the designs for his shot-proof raft, the -principle of which was afterwards developed in the turret ship. Mr. -Brunel gave Captain Coles the benefit of his advice on the various -questions involved, and allowed him to use the services of his principal -draughtsman, and to have the drawings got out in his office without -expense. - -Captain Coles, in a lecture which he delivered at the United Service -Institution on June 29, 1860, warmly acknowledged the obligations he was -under to Mr. Brunel for this act of kindness and generosity, and said -that it had greatly encouraged him to persevere in bringing his plans -into public notice. - - -_Renkioi Hospital._ - -In February 1855, after the first winter of the allied armies in the -Crimea, Mr. Brunel was asked by the War Department to undertake the -design and construction of hospital buildings for the East. - -He replied (on the same day that he received this application, February -16) that his 'time and best exertions would be, without any limitations, -entirely at the service of Government.' - -He was accordingly appointed as engineer, and proceeded to design and -superintend the manufacture of the required buildings and all their -internal arrangements. They were sent out under his supervision, and -erected at Renkioi, on the Dardanelles. All use for the buildings was -ended with the conclusion of peace; but, for the seven months during -which they were occupied, they added much to the comfort of more than -thirteen hundred sick and wounded soldiers. - -Many of the special arrangements adopted at Mr. Brunel's suggestion have -been since brought into general use; and the success of these buildings -was, to a considerable extent, influential in leading the Americans to -construct similar hospitals during their civil war. These are now (1870) -being copied in the German armies. - - * * * * * - -The history of the Renkioi hospital buildings is a striking instance of -the zeal with which Mr. Brunel entered into any undertaking which had a -claim upon his assistance, of the varied experience and fertility of -invention which he could bring to bear upon any subject, however remote -it might seem to be from his ordinary occupations, and of the minute -personal attention he was accustomed to give to every detail, as the -only certain means of ensuring success. - -Mr. Brunel entered upon his duties on February 16, and reported to the -War Office on March 5 that he had not lost any time nor spared any -exertion or any means in his power to forward the important business he -had undertaken. He stated that he availed himself freely of the advice -and assistance of all persons to whom he could apply with any prospect -of advantage; and he added, 'It is most gratifying to be able to state -that from everybody I have received the most zealous and cordial -assistance, and found it sufficient to mention the object of my -enquiries to obtain immediately every assistance I could possibly -require.' - -An experimental ward was erected a few days afterwards on the premises -of the Great Western Railway at Paddington, and was carefully criticised -by competent persons; and, the plans having been approved of, -specifications were made, with drawings of the various parts, and -tenders were invited for the construction of the buildings. - -The following paper gives a description of the buildings, and was -written by Mr. Brunel in order to satisfy the curiosity of his -friends:[l]-- - - - March 1855. - - The conditions that it was considered necessary to lay down in - designing these buildings were,-- - - First. That they should be capable of adapting themselves to any - plot of ground that might be selected, whatever its form, level, or - inclination, within reasonable limits. - - Secondly. That each set of buildings should be capable of being - easily extended from one holding 500 patients to one for 1,000 or - 1,500, or whatever might be the limit which sanitary or other - conditions might prescribe. - - Thirdly. That when erected they might be sure to contain every - comfort which it would be possible under the circumstances to - afford. And-- - - Fourthly. That they should be very portable, and of the cheapest - construction. - - The mode in which it has been sought to comply with these - conditions is as follows:--[186] - - The whole hospital will consist of a number of separate buildings, - each sufficiently large to admit of the most economical - construction, but otherwise small and compact enough to be easily - placed on ground with a considerable slope, without the necessity - of placing the floor of any part below the level of the ground, or - of having any considerable height of foundation to carry up under - any other part. - - These separate buildings have been made all of the same size and - shape; so that, with an indefinite length of open corridor to - connect the various parts, they may be arranged in any form, to - suit the levels and shape of the ground. - - Each building, except those designed for stores and general - purposes, is made to contain in itself all that is absolutely - essential for an independent hospital ward-room; so that, by the - lengthening of the corridors, and the addition of any number of - these buildings, the hospital may be extended to any degree. - - To ensure the necessary comforts, and particularly to provide - against the contingency of any cargo of materials not arriving on - the spot in time, each building contains within itself two - ward-rooms, one nurse's room, a small store-room, bath-room, and - surgery, water-closets, lavatories, and ventilating apparatus. - - The ward-room is made wide enough and high enough to ensure a good - space of air to each bed, even if these should be unduly crowded. - Each building contains two ward-rooms, intended for twenty-six beds - each, which is found in practice to be a size of room admitting of - proper control and supervision. - - With respect to closets and lavatories, after examining and - considering everything that has been done, both in hospitals of the - best description and poor-houses of the cheapest construction, it - was found that the requisite security for cleanliness and the - greatest amount of economy of labour, and of consumption of water, - could be obtained by a cheap description of water-closet designed - for the purpose; and with the same object of diminishing the amount - of labour and the waste of water, and securing cleanliness without - depending upon the constant attention of assistants, fixed basins - for lavatories and mechanical appliances for supplying and drawing - off water were adopted. - - As a protection against heat, experience in hot climates and - experiments made expressly for the purpose satisfactorily proved - that a covering of extremely thin and highly polished tin, which - reflects all direct rays of heat, was the cheapest, lightest, and - most effective protection, and every piece of woodwork not covered - with tin is to be whitewashed externally. Internally the lime-wash - has a slight tint of colour, to take off the glare.[187] - - To secure ventilation in a hot climate with low buildings extending - over a large area, and therefore incapable of being connected with - any general system of ventilation, it was considered that _forcing - in_ fresh air by a small mechanical apparatus attached to each - building would be the only effective means. Each ward-room is - therefore furnished with a small fan, or rotatory air-pump, which, - easily worked by one man, is found capable of supplying 1,000 to - 1,500 cubic feet of air per minute, or 20 to 30 feet for each - patient. This air is conveyed along the centre of the floors of - each ward-room, and rising up under foot-boards placed under the - tables, is found to flow over the floor to every part of the room. - - Besides this mechanical supply of air, opening windows are provided - along the whole length of the eaves, and spaces left immediately - beneath the roof at the two gables, amply sufficient together to - ventilate the rooms thoroughly if any breezes are stirring, without - the help of the fan. - - The light is admitted by a long range of narrow windows, - immediately under the eaves, which protect them from the direct - rays of the sun. These windows open, and are provided with shutters - inside, which exclude the light, but admit the air. - - By forcing the air into the room, instead of drawing it out, the - entrance of bad air from the closets, drains, or any surrounding - nuisances is prevented. The fan is placed at the opposite end to - the closets and drains; and all the fans being in the open - corridor, the workmen can be seen by a single sentry, and kept to - their work. - - The buildings, as now constructed, are adapted to protect the - interior from external heat. Should winter come while they are - still in use, the framework is adapted to receive an internal - lining of boarding, and the interstices can be filled with a - non-conductor. - - Two buildings, of the same form and dimensions, are fitted up with - every convenience as store-rooms and apothecaries' dispensaries. - - An iron kitchen, slightly detached from the wooden buildings, - fitted up with every contrivance capable of cooking for from 500 to - 1,000 patients, is attached. - - A similar building of iron is fitted up with all the machinery - lately introduced in the baths and washhouses of London for washing - and drying in the minimum space, and with the least amount of - labour. - - If an aggregate of buildings should be placed in one spot for more - than 1,000 patients, a second kitchen would be added, but the - single washhouse would be sufficient. - - With each set of buildings is sent a pumping apparatus, a small - general reservoir, and a sufficient length of main, with all its - branches, to supply water to every detached building; and all the - pipes and branches are of such construction as to admit of being - put together without any soldering or cement. A system of drains - is provided, formed of wooden trunks properly prepared, and of - sufficient extent to form a complete and perfect system of drainage - from every building to a safe distance from the general - hospital.[188] - - A number of small buildings, intended to be detached from the main - body, are provided for residences for the officers and servants of - the establishment, and for a small detachment of soldiers. A - slaughter-house and store-yard and some other appurtenances are - also provided, the extent of which depends on the circumstances of - each case. - - The construction of each building has been studied with very great - care, so as to secure the minimum amount of material, the least - possible amount of work in construction or erection, and the means - of arranging all the parts in separate packages capable each of - being carried by two men; and the result is that each building is - the cheapest and lightest that has yet been constructed in - proportion to the area covered. - - For the transport of the materials to the spot selected, two - sailing-vessels and three steamboats, capable of carrying one - hospital for 1,000 men, which is the first about to be sent out, - have been secured. In each vessel is sent a certain number of - complete buildings, with every detail, including their proportion - of water-pipes and drains, closets, lavatories, baths, &c., and a - small amount of surplus material and tools; and in each of two - separate vessels are sent a set of pumps and mains, and a kitchen - and washhouse. So that by no accident, mistake, or confusion, short - of the loss of several of the ships, can there fail to be a certain - amount of hospital accommodation, provided with every comfort and - essential. - - The peculiar circumstances under which these establishments are - likely to be placed have required not only peculiarities of - construction, but these, in turn, have required numerous provisions - and details specially designed for the case. - - As all the buildings, except the kitchen and washhouse, are - entirely constructed of wood, it is considered essential that no - stove or fire-place of any description should be allowed in any - part, except in the iron buildings; in these there is provision for - an ample supply of hot water, but each ward-building is provided - with a small boiler, heated by candles, which by experiment have - been found amply sufficient for all that can be required. Candles - are to be used exclusively for lighting, and lamps and lanterns - have been constructed for the purpose. - - A proper supply of fire-engines is provided, and other - precautionary measures are adopted against fire. - - The condition of portability requiring that the walls and roofs - should be of the thinnest and slightest possible construction, - protection against heat has been provided for in the manner before - referred to, and good ventilation secured by mechanical means. But, - in addition to this, there is a very simple provision made for - passing the air over a considerable extent of water surface; which - would not only cool it, but diminish the effect of excessive - dryness, which is said to be occasionally in this climate more - oppressive than even the temperature. - - As the space in the wards is very liable to be encroached upon, and - the beds crowded, portable baths have been designed, into which the - more helpless patients can be lifted, and lowered, on a frame or - sack, without requiring space for assistants to stand around, or - with the bath placed only at the foot of the bed. - - The kitchen and laundry have each required many special - contrivances. - - The instructions given to Mr. Brunton, the engineer, who has been - sent out for the purpose of erecting these buildings, are, to - commence by determining on his plan of arrangement to suit the - peculiarities of the ground, and then to construct the complete - system of drainage and to lay on the water supply before the - buildings are rendered capable of receiving patients; and all the - arrangements of the details are designed with the view of - obtaining, as the first conditions, a perfect system of drainage, a - good supply of water, free ventilation, and the most perfect - cleanliness, quite independent of labour and of the continued - attention of assistants; these conditions being assumed as - essentials, preceding even the mere covering in of space and - providing shelter for patients. - - The cost of these buildings, delivered ready for shipment, will be - from 18_l._ to 22_l._ per bed, allowing 1,000 cubic feet of space - in each ward-room to each bed. If pressing emergency should lead to - the beds being placed closer, and fifty per cent. more patients - should be introduced, it is believed that the perfect system of - ventilation which is secured would render these hospitals very - superior to any now in use for the army. - - Of the cost above named, about 12_l._ per bed is that due to the - ward-rooms themselves, with all their conveniences attached, and - the rest arises from the cost of the store-rooms, kitchen, - machinery, residences, and appurtenances. - - The cargo space required for their conveyance is about a ton and a - half to a ton and three-quarters measurement per bed. - -As the buildings were completed the work of transport was commenced; and -twenty-three steamers and sailing-vessels were despatched, containing -altogether about 11,500 tons measurement of materials and stores. The -first vessel arrived out on May 7, 1855, and the last on December 5, in -the same year. - -Meanwhile the important question of the site for the hospital buildings -was being determined by Dr. Parkes, the Medical Superintendent, with the -assistance of Mr. Brunton, who was in constant communication with Mr. -Brunel on the subject. - -After visiting various places, Dr. Parkes finally selected a spot near -the village of Renkioi, on the Dardanelles. In a report which he -addressed to the Secretary of State for War upon the formation and -general management of the hospital, he thus describes 'the nature of the -site, and the means which were used in the formation of the hospital:'-- - - The piece of land on which the hospital was placed was a shelving - bank of a light, porous, sandy soil, resting on marl; it contained - about 270 acres, stretched tongue-like into the waters of the - Dardanelles, and was bounded inland by a low range of sandstone - hills, which were themselves backed by rather lofty ranges of - oolitic limestone, intersected by deep ravines. The tongue of land - formed two bays, north and south, in both of which was good - anchorage for ships, and as the wind blew almost always up or down - the Dardanelles, i.e. from the north-east or south-west, one or - other of these bays was comparatively calm in all winds except - those which came infrequently from the west. - - The position of the spot was on the Asiatic coast, nine miles from - the mouth of the Dardanelles, in lat. 40 deg. 2', long. 26 deg. 21'. It was - the site of the port of an old Greek city, the ancient Ophrynium. - - The extreme point of this tongue of land was about 10 feet above - the sea, but from this point it rose regularly and gradually to - about 100 feet above the sea. An admirable fall was thus given for - drainage, and so gradual was the rise that the wooden houses were - placed on the ground without terracing or excavation, whereby very - great expense was saved. The extreme length from the point to a - spot too steep for the erection of houses was about half a mile, - and we were enabled thus to place down the centre of the tongue of - land no less than thirty-four houses, capable of holding 1,500 - sick, in one long line on either side of the central corridor, an - arrangement which facilitated very greatly the laying of both - water-pipes and drain-tubes. In fact, we were able to carry out the - plan which Mr. Brunel had suggested as the best. - - There was enough space on the tongue of land, on either side of - this long central line, for two shorter parallel lines of seventeen - houses each. These two lines were placed one to the north, and the - other to the south of the large central hospital. Each was capable - of containing 750 men, and one of them to the north was nearly - completed when the declaration of peace put a stop to the works. - - On the sides of the hills in rear were numerous small springs of - excellent water, which were collected together and conveyed in - earthenware pipes to a large reservoir, placed by Mr. Brunton 70 - feet above the highest house, which was itself about 60 feet above - the sea. From this reservoir the water was carried in iron pipes - down the centre of the long corridor, and at every ward (which was - placed at intervals at either side of the corridor) a leaden - service-pipe came off, and led an abundant and never-ceasing supply - into the ward cisterns, which supplied the baths, lavatories, and - closets. By this arrangement all necessity for pumping water was - avoided, and the sewers were able to be flushed very perfectly. - - The lavatories and closets were placed at the ends of the wards - most remote from the corridor, and immediately outside them ran the - two main sewers, which at their sea terminations were carried some - distance into the Dardanelles. - - The plan of the hospital may be at once understood by imagining a - covered way, open at the sides, and 22 feet wide, running nearly - east and west, and reaching for a length of more than a third of a - mile, on either side of which stood, at intervals of 27 feet on the - south side, and in most cases 94 feet on the north, the thirty-four - houses, each of which, as already said, was 100 feet long, 40 feet - wide, 12 feet high at the eaves, and 25 in the centre, and was - capable of containing fifty patients, with an allowance of nearly - 1,300 cubic feet of air for each man. Some portion of this space - was occupied by the closets and some small rooms used as orderlies' - and bath-rooms. Thirty of these houses were used as wards; four - were used as dispensaries and purveyor's stores. A drawing by Mr. - Brunton, showing the arrangements of one of the wards, is - attached.[189] - - [Illustration: Fig. 22. RENKIOI HOSPITAL. - - WARD BUILDING. - -A. Corridor -B. Ward room -C. Orderlies' bed-room -D. Bath-room -E. Medical officer -F. Lavatory, &c. -_g._ Ventilating fan -_h._ Ventilating air-trunk -_i._ Main drain -_j._ Tables in wards - - _Transverse Section._ - - _Longitudinal Section._ - - _Ground plan._ - - _Scale of feet._] - - To the south of each division of ten houses was placed an iron - kitchen, which afforded the necessary accommodation for preparing - 500 diets. - - At the inland extremity of the corridor were placed two iron - laundries, the water from which (some 4,000 gallons daily) was - passed into the sewers. Beyond the laundries were placed on either - side the wooden houses of the medical and other officers, who were - thus able to see down either side of this long line, and to - preserve to a certain extent surveillance over the patients. - - The two smaller hospitals were constructed on a similar plan, each - range having, however, only one iron laundry inland, and one iron - kitchen in the centre of the range. - - About half a mile from the hospital, close to the sea in the south - bay, three store-houses were erected, and a railway led from an - adjacent jetty or pier by the side of these store-houses to the - centre of the main hospital. Had the war continued, it would have - been carried to the north pier and bay, and would also have had a - branch running along the corridor of each hospital, so as to - deposit the sick at the very doors of the wards into which they - were to go. - - Nothing could exceed the simplicity of the whole arrangement; it - was a repetition of similar parts throughout; and experience - enables me to say, that nothing could be better adapted for a - hospital than this system of isolated buildings, between every one - of which was a large body of moving air, rendering ventilation - easy, and communication of disease from ward to ward impossible. - - The introduction of the covered way connecting the various houses - was a happy idea. In the summer this corridor was left quite open - at the sides, and formed a cool walk for the convalescents; while - in winter we boarded up its north side, so that in the coldest - blasts of the northern wind the men were protected, and were able - to leave their wards and to take exercise. I need only further - observe that, in order to secure perfect ventilation, not only were - openings left under the eaves and in the gables of the buildings - (which could be closed in cold weather), but air-shafts were placed - under the floors through which 1,000 cubic feet of air per minute - could be forced into the wards by fans placed in the corridor and - worked by hand [see fig. 22]. As the amount of wind at Renkioi was - always considerable, we never had occasion to use these machines; - but had the hospital been placed in a less airy situation, they - would have been of the greatest use. - - For the construction of this hospital every necessary part was sent - out by Mr. Brunel. The houses were erected with great care by Mr. - Brunton, assisted by Mr. Eassie, jun., and by eighteen English - workmen (thirteen carpenters, one pipelayer, three plumbers, and - one smith) sent out for this purpose. On account of the size and - height of the houses (which were many times the size of the largest - Crimean huts), the framework was obliged to be put together very - carefully, and Mr. Brunton felt it necessary to employ none but - the English workmen on this duty; consequently the erection of the - houses took much longer time than we originally anticipated; but - during the winter we had reason to be satisfied that Mr. Brunton - had done wisely, for, in spite of the heavy winds we often had, no - finished house was ever damaged, except in one or two instances to - a very slight amount. - - The erection of the houses was commenced on May 21, 1855. On July - 12, I reported the hospital ready for 300 sick; on August 11, it - was ready for 500, and on December 4, for 1,000 sick. By January - 1856, viz. seven months after its commencement, it was ready for - 1,500 sick; and when the works were discontinued, at the end of - March 1856, we could, with a little pressure, have admitted 2,200 - patients. In about three months more this immense establishment for - 3,000 sick could have been finished and in full activity. - -On the working of the system, Dr. Parkes says in his report:-- - - Although the hospital was ready for 300 patients on July 12, 1855, - we were not called on to receive sick till October 2. From that - time till February 11, eleven ships arrived from Balaclava and - Smyrna.... After February 11, 1856, we received no more sick. The - total number of military patients who were received from these - ships was 1,244, and, in addition, 87 soldiers were admitted, - either from the guard at Renkioi or Abydos, from transport ships - which touched at Renkioi, or from the English soldiers attached to - the Osmanli Horse stationed at the town of Dardanelles during the - summer and autumn. - - The total number of admissions was 1,331-- - - Cured 961 - Invalided 320 - Deaths 50 - - Besides the military patients, we admitted 77 civilians.... The - total number of patients actually treated was 1,408, the largest - number at any one time 642.... - - The anticipations we had formed of the health of the spot and of - its adaptability for a hospital were quite confirmed by the - experience of more than a year. The winter was mild, and the - climate seemed especially adapted for pulmonary complaints, of - which we had a large number. The changes of temperature, it is - true, were very sudden and great; but as the men had warm wards, - these changes were not felt, and there were few days in which the - most delicate consumptive patient could not get out into the - sheltered corridor for a short time during the day. The - construction of the hospital was admirably adapted for men - recovering from illness. As all the wards were on the ground, as - soon as a man could crawl he could get into the air either in the - cool and sheltered corridor or in the spaces round the hospital. - - * * * * * - - In April and May 1856 the greater number of the patients had been - either discharged or invalided home, and ... the medical and - nursing staff was reduced more than one-half, and ... in the middle - of July the remaining staff was sent home. - - All the stores which were likely to be used or to sell well in - England were sent home, and everything else was sold on the ground. - Major Chads, with twenty soldiers, and Mr. Brunton remained behind, - to superintend the sale of the buildings, which took place on - September 20. - - - - -CHAPTER XVI. - -_MR. BRUNEL'S PROFESSIONAL OPINIONS AND PRACTICE._ - - SCHEME OF THE CHAPTER--MR. BRUNEL'S POSITION IN RELATION TO THE - COMPANIES OF WHICH HE WAS ENGINEER--LETTER ON THE DIRECTION OF - RAILWAY WORKS IN ITALY (MARCH 4, 1845)--LETTER ON THE POSITION OF - JOINT ENGINEER (OCTOBER 16, 1843)--LETTER ON THE POSITION OF - CONSULTING ENGINEER (DECEMBER 30, 1851)--LETTER ON THE POSITION OF - THE ENGINEER IN RELATION TO THE CONTRACTORS (MAY 26, 1854)--LETTERS - ON THE POSITION OF THE ENGINEER IN RELATION TO THE DIRECTORS (APRIL - 15, 1850; DECEMBER 6, 1851; JANUARY 22, 1857)--MR. BRUNEL'S - ASSISTANTS--LETTERS ON INTERFERENCE OF DIRECTORS WITH THE ASSISTANT - ENGINEERS (JANUARY 19, 1842; JANUARY 28, 1842; JANUARY 12, - 1851)--MR. BRUNEL'S PUPILS--HIS RELATIONS WITH OTHER - ENGINEERS--INVENTORS--LETTER IN REPLY TO AN INVENTOR (SEPTEMBER 17, - 1847)--MR. BRUNEL'S VIEWS AS TO STATE INTERFERENCE--LETTER ON THE - ROYAL COMMISSION ON THE APPLICATION OF IRON TO RAILWAY STRUCTURES - (MARCH 13, 1848)--LETTER ON A PROPOSAL TO OBTAIN THE RECOGNITION IN - ENGLAND OF DECORATIONS CONFERRED AT THE PARIS EXHIBITION OF 1855 - (FEBRUARY 9, 1856)--MR. BRUNEL'S OPINION ON THE PATENT - LAWS--MEMORANDUM FOR EVIDENCE BEFORE THE SELECT COMMITTEE OF THE - HOUSE OF LORDS ON THE PATENT LAWS, 1851--EXTRACT FROM OBSERVATIONS - ON THE PATENT LAWS, MADE BY MR. BRUNEL AT A MEETING OF THE SOCIETY - OF ARTS (MARCH 26, 1856). - - -It is proposed in the earlier part of this chapter to describe, -principally by extracts from Mr. Brunel's correspondence, the position -occupied by him in regard to the Companies which he served, and to the -various classes of persons with whom he acted in the discharge of his -duties as engineer to those Companies. These selections are followed by -extracts relating to questions of general professional interest. - - * * * * * - -The first point to be considered is, his relations with the Companies -which employed him as their engineer, and with the Directors who formed -the governing body. - -Mr. Brunel conceived that he was, by virtue of his appointment as -engineer, the sole and confidential adviser of the Company in all -matters relating to the construction and mechanical working of the -undertaking. He did not permit any one to be associated with him in the -supreme control over those matters which were in his department; and the -moment he thought that confidence was no longer placed in him, he was -prepared at every sacrifice to resign his office. But, as long as he was -supported by the Directors, he thoroughly identified himself with their -cause, and he never allowed considerations of health or convenience or -pecuniary advantage to interfere with the performance of any service -which he could render them. The fearless independence of his position, -combined with his absolute devotion to the interests of his employers, -was no doubt the secret of the immense influence he acquired, and of the -affectionate esteem with which he was regarded by those whom he served. - -_On the Direction of Railway Works._ - - - March 4, 1845. - - I have well considered the communication which you did me the - honour of making on the part of the Government of His Majesty the - King of Sardinia with reference to my undertaking the direction of - the works of the proposed railway from Genoa to Alessandria, about - to be executed by the Government itself.... - - In the first place I assume that if the direction of the works be - confided to me as the engineer, the same degree of confidence will - be placed in me, and the same authority will result from that - confidence, as would be the case in England--that is to say, I - should be the confidential adviser of the Government in all - engineering questions connected with this railway, my - communications would in all matters be made direct with the - Government, and as long as I continued to be responsible for the - direction of the works no other engineer would be consulted or - allowed to interfere. Of course I claim no right to direct anything - but that which has the sanction of the Government; but I should - claim to be their sole adviser on all engineering points (connected - with the construction of the railway), and to possess their entire - confidence; and also that, if any portion of that full confidence - were at any time withdrawn, the fact should be immediately - communicated to me; when, after making every possible arrangement - to prevent inconvenience to the Government, I might withdraw from - the direction of the work. This is the position which an engineer - of any standing occupies in this country, whether acting for the - Government or for individuals; and I believe it to be as fully - essential for the success of the proposed undertaking, and as - necessary for the interests of His Majesty's Government as for my - satisfaction, that I should be placed in a similar position. - - The circumstance of my being a foreigner, of my being rarely - present to meet objections, if any are raised, of the unavoidable - frequency of real as well as apparent failures in works of such - variety and so numerous as those which occur on this line, of the - difficulties which always attend the introduction of novelties and - everything connected with a railway, the rapid mode of its - construction, the necessity which experience has proved of - frequently adopting apparently hasty and hazardous methods to - prevent the evil consequences of protracted delays,--all this will - be novelty with you as it was a few years ago in England, all these - circumstances combine to render it peculiarly essential to the - satisfactory progress of the undertaking that it should be well - known to all parties that full and entire confidence is placed in - me by the Government. - - It will of course also be necessary that all parties acting under - me in the direction of the works should feel that their appointment - or dismissal depends entirely upon me. - - In return for the confidence thus placed in me and the authority - given to me, I should of course know no interest but that of the - Government. If the Government is willing to appoint me engineer - according to this definition of my position, I shall feel pride in - the appointment, and I shall devote my best energies to the - accomplishment of one of the finest and most interesting works of - the day.... - - _On the Position of Joint Engineer._ - - - October 16, 1843. - - The contents of your letter of yesterday take me quite by surprise; - the expression you use of joint-engineership implies a view of our - relative position diametrically opposed to the views which I have - plainly and unequivocally expressed to you and to the Directors - when such a thing as joint-engineership was proposed to and - rejected by me.... - - You wind up your letter by saying 'we have accepted the duty of - joint-engineers,' &c., and you add a postscript requesting me to - lay your letter before the Directors: this I should have been - obliged to do without any such request. I never accepted the duty - of joint-engineer; I have always refused to do so. I thought I had - made this very clear both to you and the Directors on several - occasions; indeed I often feared that I expressed myself too - strongly instead of leaving it capable of misapprehension.... - -_On the Position of Consulting Engineer._ - - - December 30, 1851. - - I shall be happy to act in any capacity (subject to the exception I - will further explain) which can be useful to your Company; ... but - the exception I have to make is one which perhaps resolves itself - merely into a question of _name_. The term 'Consulting Engineer' is - a very vague one, and in practice has been too much used to mean a - man who for a consideration sells his name, but nothing more. Now I - never connect myself with an engineering work except as the - Directing Engineer, who, under the Directors, has the sole - responsibility and control of the engineering, and is therefore - 'The Engineer;' and I have always objected to the term 'Consulting - Engineer.' ... - - In a railway the only works to be constructed are engineering - works, and there can really be only one engineer; and in your case - especially, where, as I apprehend, the contractor is part of the - company, and has to be treated with consideration, and perhaps less - vigorously, at all events differently from an ordinary contractor, - considerable management and discretion will be required of your - engineer, and a degree of responsibility which I would only - undertake if sole engineer. Possibly this is what you meant, and - that I alone see the distinction, but it is an important one with - which you may not be so familiar as I am. - -_On the Position of the Engineer in Relation to the Contractors._ - - - May 26, 1854. - - I have in due course taken steps to prepare a report for the - Directors on the state of the work, but you must not apply to the - contractors for such reports. In the first place, it would lead to - ridiculous contradictions, inasmuch as most likely my reports - would differ materially from theirs; and also it would reverse the - whole order of things. I must alone, so long at least as I am the - professional adviser of the Company, be the medium of communication - with contractors in all matters which the terms of the contract - refer to me. I am very particular about the regularity of all these - forms, because, although, while all goes smooth, they are of no - consequence, yet if, unfortunately, any little difficulties arise, - then it is unpleasant and difficult to alter a previous course. - - I would ask, then, that all official communications with the - contractors should be made through me, and that, even as regards - these, we should confer together before any formal resolution - should at any time be passed, so as to be sure that it is properly - worded, and that no awkward precedent is established. - - You may have seen that a great appeal case before the Lords, - affecting claims of some hundreds of thousands, has just been - finally decided in favour of the Great Western Railway Company - after fourteen years of litigation;[190] and this favourable - decision was entirely obtained by carefully prepared - specifications, and by my not having departed in any single case, - in years of correspondence, from the letter and spirit of the - contract, and particularly from the fact--strongly commented upon - by Lords Cranworth and Brougham--that I had maintained my position - of umpire between the Company and contractor. It is, then, as - essential to the Company as to the contractor and to me that I - should maintain that position. - -_On the Relations between the Engineer and the Directors._ - -I. - - - April 15, 1850. - - You will remember that on the 2nd of November last I addressed you - a letter on the subject of my acting as umpire in several cases of - reference between the Company and contractors, who were raising - heavy claims against the Company, in which I expressed my readiness - to act in a very responsible, laborious, and thankless position.... - - I am also still acting, so far as my services can be useful, as - your engineer; and in arranging with contractors, &c., there is - even now much remaining to be done. As long as I enjoy your full - confidence, it would be a great pleasure to me, although the - profit might for the present be small, to continue your engineer, - looking forward, as I do, at no distant period to the completion of - the works; but the changes that have lately taken place in the - Board, and the excitement which has been displayed by some of your - proprietors in effecting those changes--such excitement as is too - apt frequently to lead men to form most unjust and erroneous - opinions of the trustworthiness of those who have been long engaged - in their service--very naturally causes anxiety. I, and you who - have been acting with me for so long, know that I have always - advised you honestly, and I hope generally wisely, on such matters - as I have been consulted upon, notwithstanding my known connection - with other and sometimes conflicting interests. But new men may not - have the same confidence in me, and I cannot afford to run the risk - of any doubts being entertained upon the subject. - - I must therefore beg of you to bring the matter before the Board - formally, and if it is desired that I should continue to act as - your engineer, that I may have it clearly understood that I do so - with the full concurrence of the Board as now constituted, and - particularly of the new Directors; and that to render the - expression of their confidence clear, I wish them to understand - that I am quite ready to tender them my resignation if they do not - feel that confidence, and that such resignation cannot prejudice - any of the cases under arbitration before me, as I undertook them - upon the express understanding that it was as agreed umpire, and - not as engineer to the Company. - - I shall only add that by being engineer to a Company, I mean acting - in perfect confidence with the Directors on matters generally, as I - have been in the habit of doing. - -II. - - - December 6, 1851. - - I really cannot consent to forego in this case the rule I lay down - for myself in my professional business, which is to yield as far as - I comfortably can to the mere wishes of Directors in the mode in - which I direct the works they may order, but not beyond this - point--and if the Directors of any body claim the right to control - the staff which I think necessary to carry on my work, I concede - the right at once, and resign the direction of that staff. The - staff for constructing engineering works is not a permanent - establishment, which can be extended or restricted just as a Board - of Directors may determine; it is much more of the character of a - personal staff attached to the engineer-in-chief, and by means of - which he is enabled to take great responsibility upon himself, - both in respect of the works which he executes, and the settlement - of large amounts of payments, in which settlement both the company - and the contractors are very much at his mercy. It is the duty of - an engineer of course to study economy as well as efficiency in his - staff, and to pay attention to the wishes of the Directors so far - as he can; but he must be the ultimate judge of the number and the - persons of that staff. At least, that is my rule, and I cannot - depart from it in this case. I should wish to state this as - respectfully as possible to the Board, but at the same time to - state it clearly. - -III. - - - January 22, 1857. - - ...I have replied very fully to the observations of the Directors, - but having done so I must again place my resignation in the hands - of the Directors. A Board of Directors has a perfect right to - dispense with the services of an engineer, or to lay down any rules - of conduct they may think fit, and to engineer the works - themselves, either as a body or by appointing one of their members, - if they think fit; but if they desire to have the advice and - responsibility of any respectable engineer--at all events, if they - wish to have mine--they must place the usual amount of confidence - in me; and as long as I am engineer they must leave me to conduct - the engineering, and must act as if they assumed that I was more - able to advise the Board upon all the usual practical questions of - engineering than any one of the Directors. Admitting as I do the - full right of a Board of Directors to determine whether they will - have an engineer or not, if they have one they must trust him to do - his own work. - - As a mere question of time it would be impossible that I could be - constantly entering into long explanations of the most trifling - character upon points on which I must be by far the most competent - judge--and in fact the competent and responsible judge, expressly - employed, and paid professionally because I am so. If individual - Directors are more competent than their engineer, let them assume - the office and the responsibility; but do not have a divided - responsibility. I am most happy at all times to receive any hints - or suggestions from any body whether Directors or not, but I cannot - undertake the labour of replying to them all, neither can I act as - engineer to a Board of Directors who, either as a body or by one or - two of their members, make a practice of taking upon themselves to - judge of those details of which I must be assumed to be the - competent judge, and thereby interfering with my proper duties. If - the engineer is not assumed to be worthy of trust both in respect - of zeal in the interests of the Company, and very superior to any - one of the Directors as regards experience, and ability to carry - out what the Directors may determine upon, he is not fit to be the - engineer; but if he is so, he must be left to carry out those - details of his department of the business. These are the general - principles upon which alone I can act. - -It is, from the nature of the case, impossible by any extracts from Mr. -Brunel's correspondence to give an adequate idea of the position which -he occupied in relation to his assistants. There was so much personal -intercourse between them that letter writing was but little resorted to. - -His relations with them were of the most affectionate and intimate kind, -and were maintained without any ostentation or outward show. He was in -the habit of placing entire confidence in his subordinates as long as he -considered that they deserved it; and, while he preserved his own proper -position, he was always ready to shield them from the interference of -others. The letters which are printed below are evidence of this. When, -on the other hand, anything occurred to displease him in the conduct of -his assistants, he was eager to give the offender a chance of retrieving -his position; and he was always ready to help them in any difficulties. - - -_On Interference of Directors with the Assistant Engineers._ - -I. - - - January 19, 1842. - - While I am upon the subject, and as I have referred to the impolicy - of Directors taking notice of little things, and as I speak freely - to you, I will mention that I have observed with pain on some - occasions this tendency; and I will give one instance of what I - must call most unwise interference. It was lately, and - unfortunately at the same moment as this complaint, intimated that - a pair of boxing gloves had been seen in one of the Company's - offices, and that _the Directors had observed it_. Now I really do - not know why a gentlemanly and industrious young man like ---- - should be subject to have his trifling actions remarked upon more - than I myself, unless the observer gave him credit for a much more - gentle temper than I possess; because I confess, if any man had - taken upon himself to remark upon my having gone to the pantomime, - which I always do at Christmas, no respect for Directors or any - other officer would have restrained me. I will do my best to keep - my team in order; but I cannot do it if my master sits by me, and - amuses himself by touching them up with the whip. - -II. - - - January 28, 1842. - - I am much obliged to you for your letter. I am sorry to find, - however, that the impression, a very erroneous one as I believe, - remains upon your mind that the assistant engineers are predisposed - to encourage, or at all events allow, improper conduct on the part - either of contractors or the inferior agents of the Company.... - - From some experience in these matters it is that I have come to the - conclusion that it is wise (however strange you may think the - doctrine to be) to shut one's ears and eyes really and truly to - everything which does not come forward in such a shape as to demand - and admit of an enquiry; and it is for this reason also that I do - entertain the opinion very strongly (in which you appear to differ - from me), that it is not the interest, it is not wise, and - therefore only it is not the duty of Directors to look after, or to - see into, the smaller details of the conduct of an establishment - which, being of a very temporary, changing, and uncertain - character, cannot at the best be conducted with the discipline and - regularity of a permanent establishment, in which the parties have - their clearly defined and unchanging duties, and look forward to - the permanent occupation of their places as their means of support. - - At all events, when the Directors see anything they think desirable - to correct or to modify, they can fully communicate it to me - without the possibility of giving to me any soreness of feeling, - which it is always desirable not to excite, even in the case of the - lowest menial whose best services one wishes to have and use. - -III. - - - December 12, 1851. - - With reference to your letter of December 11, stating that the - Directors 'are satisfied that great irregularities have existed, - and that they feel it to be their duty, and will not hesitate on - any occasion, to represent to me any irregularity on the part of my - staff that may come to their knowledge,' I am almost afraid, unless - in a short note you may have failed to convey to me the meaning of - the Directors, that they greatly misunderstand my feelings on the - subject; my great desire, as great as, possibly greater than even - that of the Directors, who cannot feel so personally responsible as - I do for the efficiency of my staff--my great desire I say is to - hear immediately from anybody, and particularly of course from a - Director, of any supposed irregularity; and I should feel that I - had ground of complaint even if any such report or any suspicion of - any irregularity were not immediately communicated to me. The - moment that the Directors could doubt my being as anxious as they - can be to know and to remedy any irregularity, or that they should - look upon me in such matters otherwise than as one of themselves, I - should feel that I had lost their confidence, and could no longer - carry on satisfactorily to myself my duties, and should therefore - resign them. Such must, I beg, be our relative position as regards - the future; and carrying out this principle as regards the past, I - must beg of them to tell me explicitly what are the irregularities - to which they refer as having been committed. I ought to be fully - informed of such things--indeed, nothing ought to be suspected even - without my knowing; for if _I_ ought not to know, who ought? - - As a matter of form, and to be strictly correct, I must guard - myself against being supposed to mean that I could desire or - approve of what the Directors I am sure would also disapprove - of--namely, a system of fault-seeking--because in a very numerous - staff or body of men, particularly where they have not the benefit - of permanent situations, the perfection of regularity cannot be - hoped for; what I principally seek and require of my assistants is - an honest discharge of their duties, and any departure from this it - is well known amongst them I never overlook. Have the goodness, - therefore, to ascertain for me, and to let me know immediately, - what these irregularities have been. - -A few words may here be added on Mr. Brunel's practice in reference to -taking pupils. - -Although many of his assistants had been his pupils, he did not -encourage young men to come to him with the object of learning their -profession in his office. He never absolutely declined to take pupils; -but he endeavoured, by fixing a high premium, to reduce the number of -applicants. - -He did not profess to do more for his pupils than to give them the -opportunities of seeing work, afforded by his office, and the chance of -being afterwards employed as his assistants. He attached much importance -to private study of mathematics and other branches of science. - - * * * * * - -Passing on to the position assumed by Mr. Brunel in his relations to the -profession at large;--it may be stated in a few words, that he was -desirous on all occasions of promoting its welfare by encouraging -friendly intercourse among its members, by healing strife, by -suppressing as far as he could all cant or pretension, and by setting -his face steadfastly against all attempts to fetter the freedom of -invention or to lessen the independence of engineers by State patronage -or control. - -It may appear strange to affirm of one who was foremost in almost all -the professional contests of his time, that he was zealous in healing -strife; but it is nevertheless true that Mr. Brunel, while he was a bold -and uncompromising advocate of his own schemes, was at the same time -untiring in his exertions to limit the area of controversy, to confine -it strictly within its proper bounds, and to divest it of all -personality or of anything which could lead to unpleasant feeling or -annoyance. - -His endeavours to this end were greatly helped by the friendly relations -which he maintained at all times with his professional brethren. He -never allowed any divergence of opinion to interfere with private -friendship; and, even in the height of controversy, he was glad to give, -and ready to ask for, advice on matters connected with the scientific -departments of civil engineering. - -It is but seldom that extracts have been made from Mr. Brunel's private -journals; but it may be permitted, in illustration of what has been said -on this point, to give the following passage, written during the great -contests of the year 1846. - - - May 5, 1846. - - I am just returned from spending an evening with R. Stephenson. It - is very delightful, in the midst of our incessant personal - professional contests, carried to the extreme limit of fair - opposition, to meet him on a perfectly friendly footing, and - discuss engineering points.... Again I cannot help recording the - great pleasure I derive from these occasional though rare meetings. - -Mr. Brunel's opinions on the working of the patent laws will be given -below, as following more fitly after extracts from his correspondence -relating to the position of his profession in regard to the Government; -but, before entering upon that subject, a few words may be said in -reference to a class of persons who formed a very large proportion of -his correspondents--the class of 'Inventors.' - -He used to receive numerous applications from persons who had invented, -or who thought they had invented, some useful contrivance, from a -locomotive which would save fifty per cent. in fuel over those then in -use, to a machine which, as Mr. Brunel assured its inventor, 'would not -even have a tendency to move.' He was always ready to encourage -inventions which seemed likely to produce good results, and to enquire -into their merits, if they were patented; but not otherwise, lest it -should be said that confidence had been placed in him. - -The following is one of the many letters he had to write in answer to -requests of this nature. - - - September 17, 1847. - - I could not have complied with your request of giving any opinion - upon the merits of the invention. Simple as such an act may be, it - too frequently involves one in controversy; and I never found, - before I made the rule not to give opinions, that my advice was - ever followed, if it was to discourage the inventor from further - expense and trouble. - - I should tell you in this case that the idea of dovetailing, which - in your first letter I find was the principle of the invention, had - long before been worked out in every shape and form that ingenuity - or blundering could possibly give it. - -Upon the important question how far, if at all, the practice of civil -engineers should be subject to State control, Mr. Brunel held very -decided views. He was strongly opposed both to any interference on the -part of the State with the freedom of civil engineers in the conduct of -their professional work, and to the recognition of merit by the bestowal -of honours or rewards. - -_On the Royal Commission on the Application of Iron to Railway -Structures._[191] - - - March 13, 1848. - - I regret that the Commissioners should have done me the honour of - requesting 'my opinion upon the enquiry referred to them;' because, - as it is known to one or more of these Commissioners that I have - expressed very strongly, both publicly and privately, my doubts of - the advantage of such an enquiry, and my fears of its being, on the - contrary, productive of much mischief, both to science and to the - profession, it would expose me to a charge of weakness and of - inconsistency if I were now to refrain from expressing those - opinions, which otherwise I had no idea of intruding upon the - Commissioners; and, indeed, I had hoped that, by making those - opinions known to some of the members, I might have been passed - over, and not invited to assist in the proceedings. - - I shall be most happy to communicate, as I am at all times most - anxious to do, any knowledge which I may obtain in the course of my - practice, and such intercommunication of ideas and of experience - amongst engineers I believe to be most useful; but the attempt to - collect and re-issue as facts, with the stamp of authority, all - that may be offered gratuitously to a Commission in the shape of - evidence or opinions, to stamp with the same mark of value - statements and facts, hasty opinions and well-considered and - matured convictions, the good and the bad, the metal and the dross - (and simple courtesy to the donors must prevent the Commissioners - from attempting to draw distinctions which might appear - invidious)--this, I believe, always has rendered, and always will - render, such collections of miscalled evidence injurious instead of - advantageous to science; and the facts or statements and opinions - so collected will form generally, I believe, a lower average of - information than that which is already in the possession, or at - least within the reach, of those who have occasion to study the - subject: for it is remarkable that in this particular enquiry the - Commissioners can have no peculiar means of obtaining, and, as I - believe, cannot hope to get better or more extended information - than that possessed by any one of the principal engineers of the - day; while they will be compelled to receive and to publish much - that a prudent man, acting on his own responsibility, would either - not have attended to, or would silently have rejected. This, - however, is perhaps a negative evil, or, at most, one which cannot - much affect the proceedings of the well-informed in our profession; - but the mischief which I anticipate is much more dangerous to the - progress of science. - - If the Commission is to enquire into the conditions '_to be - observed_,' it is to be presumed that they will give the result of - their enquiries; or, in other words, that they will lay down, or at - least suggest, 'rules' and 'conditions to be (hereafter) observed' - in the construction of bridges, or, in other words, embarrass and - shackle the progress of improvement to-morrow by recording and - registering as law the prejudices or errors of to-day. - - Nothing, I believe, has tended more to distinguish advantageously - the profession of engineering in England and in America, nothing - has conduced more to the great advance made in our profession and - to our pre-eminence in the real practical application of the - science, than the absence of all _regles de l'art_--a term which I - fear is now going to be translated into English by the words - 'conditions to be observed.' No man, however bold or however high - he may stand in his profession, can resist the benumbing effect of - rules laid down by authority. Occupied as leading men are, they - could not afford the time, or trouble, or responsibility of - constantly fighting against them--they would be compelled to - abandon all idea of improving upon them; while incompetent men - might commit the grossest blunder provided they followed the rules. - For, in the simplest branch of construction, rules may be followed - literally without any security as to the result. There is hardly a - branch of engineering that could have been selected which in its - present state is less capable of being made the subject of fixed - laws or instructions than the application of iron to railway - structures, and certainly there is no branch in which there is more - room for improvement, or which offers so many different channels or - directions for that improvement. - - In the quality of the material, the workmanship, or the mode of - manufacture, and in the application of it, there is every - imaginable variety, there is room for almost any imaginable degree - or nature of improvement; and unless the Commissioners are endowed - with prophetic powers, it is impossible that they can now foresee - what may be the result of changes in any one of these - conditions.[192] ... - - What rules or 'conditions to be observed' could be drawn up now - that would not become, not merely worthless, but totally erroneous - and misleading, under such improved circumstances? But above all, I - fear--nay, I feel convinced--that any attempt to establish any - rules, any publication of opinions which may create or guide public - prejudice, any suggestions coming from authority, must close the - door to improvement in any direction but that pointed out by the - Commissioners, and must tend to lead and direct, and therefore to - control and to limit, the number of the roads now open for advance. - - I believe that nothing could tend more to arrest improvement than - such assistance, and that any attempt to fix now, or at any given - period, the conditions to be thereafter observed in the mode of - construction of any specific work of art, and thus to dictate for - the present and for the future the theory which is to be adopted as - the correct one in any branch of engineering, is contrary to all - sound philosophy, and will be productive of great mischief, in - tending to check and to control the extent and direction of all - improvements, and preventing that rapid advance in the useful - application of science to mechanics which has resulted from the - free exercise of engineering skill in this country, subjected as it - ever is, under the present system, to the severe and unerring - control and test of competing skill and of public opinion. Devoted - as I am to my profession, I see with fear and regret that this - tendency to legislate and to rule, which is the fashion of the day, - is flowing in our direction. - - I must repeat my regret that circumstances should have forced me to - intrude these my opinions upon the Commissioners; but, for the - reasons I have before given, the application to me, after the part - I have taken, left me no alternative; but having expressed my - opinions, and respectfully protested against the objects and - proceedings of the Commissioners, I shall feel it my duty to attend - to their summons, and afford any information in my power. - - _On a Proposal to obtain the Recognition in England of Decorations - conferred at the Paris Exhibition of 1855._ - - - February 9, 1856. - - I regretted to be under the necessity of declining to sign the - memorial that was brought to me by a gentleman introducing himself - with your card, without an opportunity of explaining to you my - reasons; and it would be difficult to do so satisfactorily without - an opportunity of personal explanation. In a few words, however, I - will state that I disapprove strongly, and after full - consideration, of any introduction into England of the system of - distinctions conferred by Government upon individuals, whether - engaged in professions, arts, or manufactures, whose merits can be - so much better and more surely marked by public opinion. In - countries where public opinion is not so searching and so powerful - as in England, the evils of favouritism may be out-balanced by the - advantages of some means of distinguishing men. I admit the - possibility, though I doubt the fact; but I feel sure that the - evils would be far greater than the advantages in England. The few - cases of knighthood conferred in England generally follow public - opinion, though I should not wish to see this system carried - further. Such being my opinion, I could not consistently ask for my - own letter of Chevalier de la Legion d'Honneur being recognised - here. - -On the question of the patent laws, Mr. Brunel held the opinion that the -system of protecting inventions by means of letters patent was -productive of immense evil. The prominent part which he took in all -discussions upon this subject exposed him to much adverse criticism, -which was perhaps the more freely bestowed, because it was felt that he -was a very formidable opponent, not only from the force of his -arguments, but also from the authority with which he spoke. - -He was, from the necessity of his position as a civil engineer, himself -an inventor; he had in his staff and among those with whom he acted many -inventors; he did not, therefore, underrate the benefits conferred on -science by those who, by inventing, add to its resources. He was -continually being trammelled and thwarted in his various undertakings by -patents, and he therefore could judge of their evil effects upon the -progress of practical engineering; and, lastly, he had the best possible -means of judging of their effects upon the inventors themselves, both -from his opportunities of becoming acquainted with the fate of others, -and from his own experience. His father, Sir Isambard Brunel, had taken -out patents for most of his inventions, and, as Mr. Brunel stated before -the House of Lords Committee of 1851, with very unfortunate results, -especially in the case of the carbonic-gas engine (see Note B to Chapter -I); where, if they had not been obliged to work secretly, in order to -conceal the process before the patent was granted, they could have -obtained valuable advice, which might either have led to an earlier -abandonment of the project, or to its improvement in those points in -which it failed. - -Mr. Brunel drew up the following statement when asked to give evidence -before the Select Committee of the House of Lords in 1851. His evidence -will be found at p. 246 of the Minutes of Evidence (ordered to be -printed July 1, 1851). - - _Memorandum for Evidence before the Select Committee of the House - of Lords on the Patent Laws, 1851._ - - I have for many years had considerable experience of the operation - of patents. - - I have been engaged under my father in the working out of numerous - inventions of his, and the taking out of patents on his account, - also in advising others professionally with him, and by myself, and - have been engaged in numerous questions of disputes resulting from - patents; and I have had frequent occasion to use the patents and - inventions of others. I have also had to introduce improvements of - my own without patents, and to defend my use of them against - patents. - - I have thus for the last twenty-eight years been in the midst of - everything connected with inventions, and in constant contact with - the operation of the patent laws. - - I have been behind the scenes the whole time. - - The result has been that I have never taken out a patent myself, or - ever thought of doing so; and I have gradually become convinced - that the whole system of patents is, in the present advanced state - of arts and science and manufactures, productive of immense evil. - - I think that it does nothing of what it professes to do, and which - I believe to be impracticable in the present state of things, but - that, on the contrary, it impedes everything it means to encourage, - and ruins the class it professes to protect, and that it is - productive of immense mischief to the public. - - I should wish to observe that my opinions are not formed from any - theory, or from any consideration of what are or ought to be the - laws of patents, or whether the details of such laws are capable of - improvement or otherwise; but they are simply the result of a very - long and tolerably intimate knowledge of the operation of the hope - of protection held out, and the operation of that protection such - as it can be when obtained; and these results do not, in my - opinion, depend at all upon any question of whether patents are - cheap or dear, whether they are granted sparingly or profusely, by - a simple or by complicated machinery; it is the ruinous effects - upon the class of inventors, of the false dreams and hopes excited - by the system, and the injurious effect upon improvements of the - greater or less degree of exclusive privilege which is attained, - which I have had constantly before my eyes for so many years, and - which must be increased by any real improvement of the patent laws. - - I should, therefore, be an advocate for very cheap patents granted - with great facility, to the poor illiterate workman, as well as to - the rich manufacturer with his counsel and agents, and as well - protected as legal ingenuity can devise. - - If the system is good in principle it must bear extension, but I - believe it could not stand a twelvemonth under such a test--every - evil now inherent in the system would be greatly increased in - quantity, and the absurdities which are now ascribed to errors of - detail would all become so evident that the system would be - abandoned by universal consent. - - I believe, paradoxical as it may seem, that the privileges thus - promised and granted to inventors are most injurious to them. To - understand this, it must be known and borne in mind that useful - inventions or improvements in the present day, certainly in nine - hundred and ninety-nine cases out of a thousand, are not new - discoveries, but generally slight modifications of what is already - in use; judicious applications of known principles and of - well-known and common parts of machinery, or of common substances, - very often mere revivals or re-inventions of something which had - many times previously been thought of, and perhaps tried, and - failed from the want only of some substance or of some tool which - has since been introduced. - - I believe that the most useful and novel inventions and - improvements of the present day are mere progressive steps in a - highly wrought and highly advanced system, suggested by, and - dependent on, other previous steps, their whole value and the means - of their application probably dependent on the success of some or - many other inventions, some old, some new. I think also that really - good improvements are not the result of inspiration; they are not, - strictly speaking, inventions, but more or less the results of an - observing mind, brought to bear upon circumstances as they arise, - with an intimate knowledge of what has already been done, or what - might now be done, by means of the present improved state of - things, and that in most cases they result from a demand which - circumstances happen to create. The consequence is that most good - things are being thought of by many persons at the same time; and - if there were publicity and freedom of communication, instead of - concealment and mystery, ten times or a hundred times the number of - useful ideas would be generated by each man, and with less mental - effort and far less expenditure of time and money. - - In the present state of things, if a man thinks he has invented - something, he immediately dreams of a patent, and of a fortune to - be made by it. If he is a rich man he loses his money, and no great - harm is done; but if he is a workman, and a poor man, his thoughts - are divided between scheming at his machine in secret, and scheming - at the mode of raising money to carry it out. He does not consult - his fellow-workmen, or men engaged in the same pursuits, as to - whether the same thing had ever been tried, why it had failed, - what are the difficulties, or (what is most probable) whether - something better is not already known, and waiting only the demand. - In nine cases out of ten he devotes his time and money to the idea, - instead of pursuing his legitimate and natural pursuits. In - elaborating this idea his whole thoughts are turned to the means of - making it different from what he may happen to know of similar - ideas, so that he may secure a patent, rather than to an honest - endeavour to obtain the most useful result. He does not make use of - other good ideas which may be already patented or in use, even if - he knows of them, because his sole object thenceforth is not - improvement, but 'exclusive right.' After much time and money spent - in experiments, he takes out a patent. I will assume that the mere - patent costs him nothing, but the waste of time and money in - elaborating his idea is generally considerable, and far more - serious in its effects upon the man than the payment of the fees - now demanded for a patent. When his patent is complete, and his - invention published, the chances are, and ever will be, one hundred - or one thousand to one that it is not worth a sixpence as an - exclusive right which others will buy of him: every chance is - against him. - - _In the first place_ it must be a good thing, it must be an - improvement upon the very 'best thing' of the same sort: the - chances are of course great against this. - - _Secondly._--It must be new, nothing of the sort must have been in - use before--how very few things can be devised which will bear this - test. I do not know of half-a-dozen clear cases of distinctly new - inventions since I have been acquainted with machinery and science; - and, judging from analogy, I cannot bring my mind to believe that - these would bear the test of a strict and searching enquiry by - interested parties. The chances are then immensely against his - invention, if good enough to be disputed, proving to be new enough - to stand as giving a claim to exclusiveness. - - _Thirdly._--It must not depend for its success upon the use of some - other exclusive and privileged invention, or else of course it is - of little saleable value, even if not an infringement upon the - previous patent. - - _Fourthly._--There must be a demand existing or creatable for the - article produced; or, like many other good things, it will be out - of time, and drop accordingly. - - _Fifthly._--He must find some parties whose interest it is to - encourage the introduction of the change, and who have the means of - combating those interests which are embarked in previous - monopolies. - - Since all these conditions are necessary for success, it is not - surprising that the result should be, as I am positive that it is - in practice, that the aggregate of individual benefit derived by - the exclusive privileges granted, is greatly below the aggregate - expenditure of time and money involved in the production of the - whole, taking the good and bad; but the proportion of the aggregate - benefits as compared with the cost to the real inventor is still - less. - - It is known to all persons acquainted with the subject that, in - nine cases out of ten of successful inventions, the patents are not - beneficially enjoyed by the original inventor. And it always must - be so. The mere original invention forms generally but a small part - of the whole business or merit of bringing into useful operation - any new thing. Judgment, a knowledge of the world, and of business - and other qualities not particularly belonging to inventors, are - just as requisite as mere ingenuity, although they are not the - subject of protection. Capital and connection are also generally - required. All these command, as they ought to do, a large share in - the ultimate profits, but it is rare that an inventor at once finds - such a partner. The invention generally changes hands once or - twice, or oftener, till some chance brings it into operation; and - ultimately it is (as must be admitted by all who know anything - about these matters) very rarely, even in the case of good things, - that the party who originated the subject of the patent has - ultimately any large beneficial interest in it; and certainly, from - these and all the other causes mentioned, it is an undoubted fact - that inventors, on the whole, make a heavy annual loss, quite - irrespective of mere patent fees, by inventions and patents, and - that patents are not therefore a benefit to the present class of - inventors, and particularly not to the poorer members of the class. - - Without the hopes of any exclusive privileges, I believe that a - clever man would produce many more good ideas, and derive much more - easily some benefit from them. It is true that he will aim only at - earning a few pounds instead of dreaming of thousands; but he will - earn these few pounds frequently, and without interfering with his - daily pursuits; on the contrary, he will make himself more useful. - - An observing man sees what he thinks to be a mode of increasing the - production of a certain machine or manufacturing operation in which - he is engaged, or a better mode than that which he is acquainted - with of producing some article. In all probability the same - circumstances which led him to make the observation have attracted - the attention of others before him; perhaps, at the same time, a - little free communication with his fellow-work men or with other - manufacturers or men of science would show him that there were - insuperable difficulties, and he would turn his attention at once - to other things, or that there were better ways of doing the same - thing, or, by pointing out difficulties, enable him to avoid - useless investigations, or to make a change that would vastly - improve his scheme; or he would communicate his ideas, instead of - wasting his time in elaborating them, which very possibly others - more acquainted with the particular branch would do much better - than he; if he is a workman, his master would give him something - for the idea, or if not, his value as a workman would soon become - known. It is a great error to suppose that stupid men can live upon - the clever man's brains if they are all left free scope in the use - of their intellect; but if by artificial means an exclusive right - or property in an idea can be secured, then of course the thief may - steal the idea, and having registered his property in it, his - inferiority of intellect is more than counterbalanced. Intelligent - men who would always be suggesting improvements in a manufactory - would soon become necessary, and would be valued accordingly. A - manufacturer who was not surrounded by such assistants would stand - no chance in the general competition, and what is necessary and - valuable will in England fetch its price; and thus clever workmen - will get well paid, and earn much more, and that more healthily, - than the whole body of schemers now do. - - The impediments thrown in the way of improvements by the existence - of patents will hardly be credited by those who are not familiar - with the operation of them. In the present state of things they - create such barriers that it is almost wonderful that any - improvements can be effected. - - It will not be difficult to understand that, from the infinite - number of patents that are now taken out, it is hardly possible to - devise a mechanism or a chemical combination that does not, in some - shape or other, form part of some previous invention or process. - This would be the case even if patents were only taken out to - secure real, or what are believed to be real, inventions. But the - shoals of patents have brought into existence animals to feed upon - them. There is a trade which nothing can destroy as long as patents - last, and which must increase with the increase of patent, whatever - may be the mode of granting them. Patents are taken out even in - very general terms, so as to embrace everything that can resemble - some probable or imaginary improvement, and then, like a spider in - his web, the patentee watches for his victims. Besides this, the - honest but trading patentee, the more completely to secure a - monopoly, often takes out several separate patents for nearly the - same thing in different forms, some avowedly worthless. In doing - this, without even intending it, he includes combinations, any - beneficial application of which perhaps never crossed his mind, and - which, in the shape in which he suggested them were good for - nothing, but which nevertheless more or less prevent anybody else - from touching them, even to make a good thing. - - Again, the most respectable houses take out patents merely to - secure a monopoly of some one form of article without much regard - to the superiority of it. The result of all this is that it is - almost impossible now to introduce the slightest real improvement - in anything without infringing upon some patent, and exposing - oneself to be proceeded against by some patentee. - - The extent to which improvements are impeded by this state of - things is hardly conceivable, except to those who, like myself, are - daily suffering under it. - - There is another very serious evil produced by the system. In - taking out a patent, the necessity for avoiding all claim to - anything that can be shown to have been patented or in common use - before compels you in most cases to seek rather what part of it can - best be patented than what it is that is good in the invention. - Comparatively trivial points are frequently patented in order to - secure the monopoly of that which, although it constitutes the - merit of the invention, may not happen to be so new in every - respect as to admit of a patent. When the patent is taken, other - modes of carrying out the real invention are discovered; these - modes are patented and the original patentee is obliged to lose the - benefit of his invention or to buy up these new patents. There are - instances where enormous sums have been spent in this manner to - protect an original invention. - - And, lastly, there is an evil which acts like a numbing disease on - all improvements; a patentee frequently dares not himself introduce - improvements in any apparatus or process which he has patented, for - fear of thus injuring his patent; and I have seen numerous cases of - very important inventions where all improvement has been thus - checked and resisted by the very parties most capable of effecting - them, and who would have brought great talent and zeal to the work - if they had been free. - -_Extract from Observations on the Patent Laws made by Mr. Brunel at a -Meeting of the Society of Arts._ - - - March 28, 1856. - - He did not agree at all as to the advantages of patents. He quite - agreed as to the desirability of protecting, as far as possible, a - man's property, whether it was in the power of invention, or any - other good thing that was within him, and still more would he - protect in every possible way the property in inventions of those - who possessed but little other property--the powers of the inventor - and the ingenuity of the workman; but, having had some considerable - experience with patentees, manufacturers, and workmen, he was of - opinion that any practical benefits derived from the patent laws - did not compensate for the injury inflicted. He believed, on the - contrary, that both the inventors and the public greatly suffered - from the attempt to protect inventions. He had had great experience - on this subject, being compelled daily to examine inventions of - various kinds, and having himself constantly to invent in the - occupations in which he was engaged. Having, then, all his life, - been connected with inventors and workmen, he had witnessed the - injury, the waste of mind, the waste of time, the excitement of - false hopes, the vast waste of money, caused by the patent laws, in - fact, all the evils which generally resulted from the attempt to - protect that which did not naturally admit of protection. He agreed - as to the abstract desirability of protecting inventors in some - way, provided it did not foster unhealthy invention, as he thought - it desirable to protect every species of property that existed. He - was disposed to encourage every step towards facilitating the - obtaining patents; he hoped they would be made dirt cheap, as he - thought that would be the most effectual way of destroying them - altogether. Therefore, whenever he had been consulted on the - subject of the patent laws, he had always advocated the rendering - of patents as open and free and cheap as possible; in the first - place, because he saw no reason for attaching a price to them, and - next, because they would sooner arrive where the principle would be - fully tested. We were already nearly arrived at that state of - things when engineers were almost brought to a dead stand in their - attempt to introduce improvements, from the excess of protection. - He found that he could hardly introduce the slightest improvement - in his own machinery without being stopped by a patent. He could - mention a striking instance, in which, a few months ago, wishing to - introduce an improvement that he thought would have been valuable - to the public in a large work on which he was engaged, he had no - sooner entered upon it, with a willingness to incur considerable - expense in the preliminary requirements and in the trial of it, - than he was stopped by a patentee; but he was fortunate enough to - find that another patent existed of the same thing, and a week - after a third appeared. There was thus, fortunately, a probability - that, by the destruction of all value in any of the patents, he - might be able to continue the improvements he was desirous of - introducing. - - - - -CHAPTER XVII. - -_PRIVATE LIFE._ - - REMINISCENCES OF MR. BRUNEL'S PRIVATE LIFE--REMOVAL TO 18 DUKE - STREET, WESTMINSTER--HIS MARRIAGE, 1836--SPECIAL CONSTABLE IN - 1848--MR. BRUNEL'S LOVE OF ART--HIS JOURNEY TO ITALY, - 1842--ACCIDENT WITH THE HALF-SOVEREIGN, 1843--PURCHASE OF PROPERTY - IN DEVONSHIRE, 1847--HIS LIFE AT WATCOMBE--THE LAUNCH OF THE 'GREAT - EASTERN,' 1857--MR. BRUNEL'S FAILING HEALTH--JOURNEYS TO - SWITZERLAND AND EGYPT, 1858--LETTER FROM PHILAE (FEBRUARY 12, - 1859)--HIS LAST ILLNESS--HIS DEATH (SEPTEMBER 15, - 1859)--FUNERAL--ADDRESS OF JOSEPH LOCKE, ESQ., M.P., AT THE - INSTITUTION OF CIVIL ENGINEERS (NOVEMBER 8, 1859). - - -Under any circumstances, and by whomsoever made, the attempt to describe -Mr. Brunel's home life must fail to satisfy those who knew him, and who -remember him in the midst of his family or among his friends. - -But those who did not know him, except as a professional man, or who are -only acquainted with his works, will expect to find in these pages some -account of his private life, and of the manner in which he spent those -brief intervals of relaxation which he permitted himself to enjoy. - - * * * * * - -Although Mr. Brunel was never an idle man, he was able, until he -obtained business on his own account, to enjoy many amusements from -which in after life he was completely debarred. - -This arose partly from his work under his father being near his own home -and his friends, and partly from the power he possessed, and which never -deserted him, of being able to throw aside cares and anxieties and to -join with the utmost zest in passing amusements. - -The following letter, relating to this time, is written by one who was -Mr. Brunel's constant companion during the period to which it refers:-- - - - June 28, 1870. - - 'Dear Isambard Brunel,--I will endeavour to supply you with some - reminiscences of your father, before he became a public man, and - was engrossed by the very severe labour of his profession. - - 'The most striking feature in his character as a young man, and one - which afterwards produced such great results, was an entire - abnegation of self in his intercourse with his friends and - associates. - - 'His influence among them was unbounded, but never sought by him; - it was the result of his love of fair play, of his uniform kindness - and willingness to assist them, of the confidence he inspired in - his judgment, and of the simplicity and high-mindedness of his - character. - - 'From 1824 to 1832 he joined his friends in every manly sport; and - when, after his accident at the Tunnel, he was obliged to withdraw - from more violent exercise, he was still ready to co-operate in the - arrangements required to give effect to whatever was in hand. - - 'Whether in boating, in pic-nic parties, or in private theatricals, - he was always the life and soul of the party; for his skilful - arrangements, as well as his never-failing invention and power of - adaptation of whatever came to hand, made him the invariable leader - in every amusement or sport in which he took part. - - 'To ensure the success of his friends in a rowing match against - time, from London to Oxford and back, in 1828, he designed and - superintended the building of a four-oared boat, which, in length - and in the proportion of its length to its breadth, far exceeded - any boat of the kind which had then been seen on the Thames. - - 'During that portion of the period to which these notes refer, when - your father was engaged at the Tunnel works, the freshness and - energy with which he joined in the amusements of his friends after - many consecutive days and nights spent in the Tunnel--for - frequently he did not go to bed, I might almost say, for weeks - together--surprised them all. - - 'His power of doing without sleep for long intervals was most - remarkable. He also possessed the power, which I have never seen - equalled in any other man, of maintaining a calm and even temper, - never showing irritation even when he was bearing an amount of - mental and bodily fatigue which few could have sustained. His - presence of mind and courage never failed him, and it was - especially exhibited after the first irruption of water into the - Tunnel, when he descended in the diving-bell to examine the extent - of the disturbance of the bed of the river, and the injury, if any, - which had been done to the brickwork. - - 'The bell could not be lowered deep enough, and he dropped himself - out of the bell, holding on by a rope, and ascertained by careful - examination that the brickwork was uninjured. - - 'He was several minutes in the water; and upon this fact being - stated, many persons, and I think the officers of the Royal Humane - Society, denied the possibility of his retaining his consciousness - so long in the water, forgetting, which he did not, that his lungs - were filled with air at two and a half atmospheres' pressure. - - 'In 1830, he joined the Surrey Yeomanry and attended drill, and was - out with the troop to which he belonged on several occasions. - - 'In this capacity he was as popular as in every other; but his - remarkable talent in obtaining personal influence, even among those - with whom he was comparatively a stranger, was about this time most - usefully exhibited during the election of his brother-in-law as - member for Lambeth. - - 'He made friends and conciliated opponents among all classes of - electors--especially among working men, large bodies of whom he met - on several occasions--and among all shades of politicians; and to - his energy, good judgment and skilful arrangement of electioneering - details, which were not then so well understood as they now are, - very much of the success achieved was due. - - 'No one, I believe, ever saw him out of temper or heard him utter - an ill-natured word. He often said that spite and ill-nature were - the most expensive luxuries in life; and his advice, then often - sought, was given with that clearness and decision, and that - absence of all prejudice, which characterised his opinions in - after-life. - - 'All his friends of his own age were attached to him in no ordinary - degree, and they watched every step in his future career with pride - and interest. - - 'In fact, he was a joyous, open-hearted, considerate friend, - willing to contribute to the pleasure and enjoyment of those about - him; well knowing his own power, but never intruding it to the - annoyance of others, unless he was thwarted or opposed by - pretentious ignorance; and then, though at times decided and severe - in his remarks, he generally preferred leaving such individuals to - themselves, rather than, by noticing them, to give prominence to - their deficiencies. - - 'His appreciation of character was so exact, and his dislike to - anything approaching to vulgarity in thought or action or to undue - assumption was so decided, that to be his friend soon became a - distinction; and the extent to which his society was sought, not - only in private life, but in the scientific world, at this early - period, marked strongly the distinguishing features of his mind and - character. - - 'In 1825 and 1826 he attended the morning lectures at the Royal - Institution, and the eagerness and rapidity with which he followed - the chemical discoveries which were then being made by Mr. Faraday, - showed the facility with which he gained and retained scientific - knowledge. - - 'To write more would lead me to the events of a later period of his - life, in the history of which you require no aid from me; - nevertheless, I cannot refrain from adding a few words upon your - father's personal and professional character, which was not, in my - opinion, adequately appreciated by the public. - - 'His professional friends before his death, and his private friends - at all times, well knew the genius, the intense energy, and - indefatigable industry with which every principle and detail of his - profession was mastered; and both knew and valued the high moral - tone which pervaded every act of his life. - - 'The public, however, did not see him under the same circumstances. - - 'Their imperfect acquaintance with his character arose in a great - degree from his disregard of popular approbation, for he was never - so satisfied with his own work as to feel himself entitled to - receive praise in the adulatory style of modern writing, and he - preferred to work quietly in his own sphere, and to rely on the - intrinsic merits of his undertakings bringing their reward, rather - than to court temporary popularity. - - 'The rapidity with which he gained a high position as a civil - engineer is the best evidence of his talents. He passed almost - direct from boyhood to an equality with any one then in the - profession--a position attained by the rapidity and accuracy with - which he could apply theory to practice, and support his - conclusions by mathematical demonstrations. - - 'This knowledge, always used without ostentation, soon placed him - above most of his contemporaries; and his intimate acquaintance - with the strength and peculiarities of the various materials he had - to employ, and of the best and most economical mode of applying - them, impressed both directors and contractors with a degree of - confidence in his estimates and opinions which no one had before - possessed. - - 'His power of observation was singularly accurate; he was not - satisfied with a hasty or superficial examination, nor with the - mere assertion of a fact; his mind required evidence of its - correctness before he could receive and adopt it. I may illustrate - this by a reference to the experiments he made with French - mesmerists, and the pains he took to expose the farce of - table-turning and its accompanying follies. - - 'My object, however, by this addition to my note, is to dwell upon - the fact that he left a mark upon his profession which cannot be - obliterated. He set up a high standard of professional excellence, - and endeavoured to impress on all who were associated with him, or - under him professionally, that to attain the highest honours - required the strictest integrity, sound mathematical knowledge, - originality and accuracy of thought and expression, both in _viva - voce_ descriptions and in designs and working drawings, and a - practical acquaintance with the durability and strength of - materials, so as to know the best conditions under which each might - be applied. - - 'It was his excellence in these respects, when still young, which - soon earned for him a great reputation as a witness before the - Committees of the Houses of Parliament. - - 'His calmness and unobtrusive manner, when under severe - examination, or while attending public meetings, led many to think - him cold, and regardless of the feelings or interests of those with - whom he was associated; but nothing was further from his character, - as every one knew who was engaged in the consultations upon the - result of which future proceedings depended. - - 'He was a prudent and cautious, but bold adviser, and a - warm-hearted and generous friend. - - 'Yours faithfully, - 'W. HAWES. - - 'Isambard Brunel, Esq.' - -The events of the year 1835 brought with them, not unnaturally, other -changes. At the beginning of 1836, he removed to 18 Duke Street, -Westminster, a large house looking on St. James's Park, and now (1870) -the last in the street, next to the new India Office. - -In July of the same year he married the eldest daughter of the late -William Horsley, and granddaughter of Doctor Callcott. Of this marriage -there was issue two sons and a daughter, all of whom survive him. - -Although, as will be presently mentioned, he afterwards bought some -property in Devonshire, the Duke Street house was always his home. He -spent his life there, having his offices on the lower floors. - -He had no wish to enter Parliament, although it had been more than once -suggested to him to do so, and his work prevented his taking an active -share, as an inhabitant of Westminster, in the concerns of his -neighbourhood. - -The only occasion on which he took a prominent part in local affairs -was as a special constable in April 1848, when he acted as one of the -two 'leaders' of the special constables in the district between Great -George Street and Downing Street. - -He was not without experience of the duties of a special constable, as -he had been sworn in during the Bristol riots of 1830, and on that -occasion saw active service. Happily, matters were better managed in -London, and no actual collision took place between the constables, or -the military, and the mob. - - * * * * * - -The extent to which Mr. Brunel kept his works in his own hands, and -under his own superintendence, made it necessary for him to have a large -amount of office accommodation; and the inconvenience of having branch -offices in the streets near his house led him, in 1848, to enlarge his -offices: with this object he added the adjoining house, 17 Duke Street, -which he rebuilt. A large room on the ground floor, looking on the Park, -was thenceforward his own office, and the room above was made the -dining-room. It was decorated in the Elizabethan style, and was to have -contained a collection of pictures illustrative of scenes in -'Shakespeare,' painted for him by the principal artists of the day. This -project was never completely carried out, but several pictures (about -ten in all) were painted and hung up, among them the 'Titania' of Sir -Edwin Landseer. These subjects are again referred to in the following -letter:-- - - - February, 1870. - - 'My dear Isambard,--You ask me to jot down for you any - reminiscences I have of your father's love and feeling for art. - - 'I remember with singular distinctness the first time I ever saw - him, when I was a lad of fourteen, and had just obtained my - studentship at the Royal Academy. He criticised with great keenness - and judgment a drawing which I had with me, and at the same time - gave me a lesson on paper straining. From that time till his death - he was my most intimate friend. Being naturally imbued with - artistic taste and perception of a very high order, his critical - remarks were always of great value, and were made with an amount of - good humour which softened their occasionally somewhat trying - pungency. He had a remarkably accurate eye for proportion, as well - as taste for form. This is evinced in every line to be found in his - sketch books, and in all the architectural features of his various - works. - - 'So small an incident as the choice of colour in the original - carriages of the Great Western Railway, and any decorative work - called for on the line, gave public evidence of his taste in - colour; but those who remember the gradual arrangement and fitting - up of his house in Duke Street will want no assurance from me of - your father's rare artistic feeling. He passed, I believe, the - pleasantest of his leisure moments in decorating that house, and - well do I remember our visits in search of rare furniture, china, - bronzes, &c., with which he filled it, till it became one of the - most remarkable and attractive houses in London. Its interest was - greatly increased when he formed that magnificent dining-room, now, - with the house of which it was a part, pulled down. This room, hung - with pictures, with its richly carved fireplace, doorways, and - ceiling, its silken hangings and Venetian mirrors, lighted up on - one of the many festive gatherings frequent in that hospitable - house, formed a scene which none will forget who had the privilege - of taking part in it. When from time to time he went abroad, and - especially in his visit to Venice in 1852, he added to his - collection by purchases made with great judgment and skill. In - buying pictures, your father evinced a taste often found in men of - refined mind and feeling--viz. a repugnance to works, however - excellent in themselves, where violent action was represented. He - preferred pictures where the subject partook more of the suggestive - than the positive, and where a considerable scope was left in which - the imagination of the spectator might disport itself. This feeling - was displayed in a great love of landscape art, and in the keenest - appreciation of the beauties of nature. It is an interesting fact - to record, and one which I often heard him mention, when his - friends were admiring his beautiful grounds at Watcombe, that in - the old posting days, when travelling on the cliff road between - Teignmouth and Torquay, he constantly stopped the carriage to get - out and admire the view which he had discovered from a field at - Watcombe, little thinking then that it would ultimately be the site - of his intended country home. - - 'When your father and I went to Italy together in 1842, posting - from Westminster to Rome and back again, I had ample opportunities - of observing his love and enthusiasm for nature and art. - - 'Overwhelmed as he was with work in England at the time, it was no - easy matter for him to leave the country for a couple of months; - and I remember that our starting at all was uncertain up to the - last moment; and that, an hour before quitting London, it was only - by a _coup de theatre_, which he most adroitly performed, that he - escaped the serving of a subpoena, the bearer of which had - actually penetrated to the dining-room door in Duke Street. - - 'We left London one evening in April 1842. During our journey we - constantly passed several consecutive days and nights in the - carriage; and I am sure there was not one of our waking hours in - which some incident of interest did not occur. - - 'I remember your father agreeing with me, that our experiences - merely of post-boys and their various characteristics would be - worthy of recording in detail--from Newman's two smart lads, who - took us the first stage out of London, on to the genuine - "postillon" (boots and all) we found at Calais; then to the wild - young brigands (in appearance) who, inspired by the prospect of - extra "buon mano," whirled us along the road from Civita Vecchia - towards Rome, and winding up with the stolid German who rose slowly - in his stirrups, and distracted us by a melancholy performance on - the horn slung round him, and which no entreaty would induce him to - give up. - - 'We posted from Calais, _via_ Paris, to Chalons-sur-Saone, - marvelling the whole way whereabouts "La Belle France" was to be - found; for a drearier and more utterly monotonous ride of something - like 800 miles it is impossible to conceive. From Chalons we went - down the river to Lyons, then onwards, visiting Nismes, and through - Arles to Toulon. - - 'From Toulon we went through Cannes and Nice and along the lovely - Cornice road to Genoa. Your father was intensely delighted with - this portion of the journey. Those wonderfully picturesque towns, - with their roccoco churches looking like toys, and painted all over - upon the principle of colour generally developed in that species of - art, especially interested him. The streets were so narrow that it - was sometimes doubtful whether the carriage could be squeezed - through, and more than once it grazed the houses on either side as - it passed on. - - 'The work for which your father had come to Italy commenced at - Genoa, and he was met there by a staff appointed by the Government - to accompany him during his stay. - - 'While at Genoa he came to me one morning and said, that, in - consequence of some delay, he had a week in which to make complete - holiday, and gave me the choice of Florence or Rome. I need - scarcely say that I chose Rome, and for three days we were in the - Eternal City, seeing more in that time than those to whom we - related our proceedings could believe. - - 'How well do I remember our entering Rome by the gate on the Civita - Vecchia road, and standing up in the carriage to get our first view - of St. Peter's, and, having seen it, the blank look of - disappointment we turned on each other at the sight! But the - interior of the great church as far exceeded our expectations as - the exterior had fallen short of them. - - 'We were back at Genoa to the minute your father had appointed; and - the work being completed there, we went on to Turin. Here we were - in time to be present at the Court balls and ceremonies consequent - upon the marriage of the present King of Italy. - - 'From Turin we proceeded to Milan. - - 'At Milan your father parted from his staff, and completed the work - he had undertaken as far as it was necessary to do so in Italy. - From Milan, therefore, our journey home was one of uninterrupted - enjoyment through those glorious Lombard towns to Venice, which - happily we reached in a gondola from Mestre, and not by a railway - viaduct; then through the Tyrol to Munich, and so down the Rhine to - Belgium, reaching home from Antwerp. - - 'Thus was completed an expedition in which there was neither hitch - nor disagreeable adventure of any kind, and upon which I look back - with unmixed pleasure. - - 'The next and last time that your father and I journeyed on the - Continent together was in April 1848, when he wished to see Paris - in Republican garb, and asked me to accompany him. - - 'We were there for some days, and, armed with cards of admission, - on which our names were inscribed with the prefix of "Citoyen," - heard and saw the various celebrities of the hour. - - 'Affectionately yours, - J. C. HORSLEY. - - 'Isambard Brunel, Esq.' - - - -Within less than a year of Mr. Brunel's return from his visit to Italy, -a strange accident happened to him, which placed his life in great -jeopardy. - -On April 3, 1843, he was amusing some children at his house by the -exhibition of conjuring tricks, when, in pretending to pass a -half-sovereign from his ear to his mouth, the coin he had placed in his -mouth slipped down his throat. After a few days he began to suffer from -a troublesome cough, and on April 18 Sir Benjamin Brodie was consulted. - -The nature of the accident and the course of treatment adopted are -described in the following letter from Mr. Brunel's brother-in-law, the -late Dr. Seth Thompson, which was published in the 'Times' newspaper of -May 16, 1843:-- - - I shall be much obliged by your giving insertion to the following - statement of the treatment pursued by Sir Benjamin Brodie in the - case of Mr. Brunel, it being the wish of Mr. Brunel and his friends - that the true facts should be known, as a just tribute to the skill - of this eminent surgeon, and as a guide to future practice. The - accident happened on April 3; Sir B. Brodie was consulted on the - 18th, and his opinion was that the half-sovereign had passed into - the windpipe. The following day Mr. Brunel strengthened this - opinion by a simple experiment. He bent his head and shoulders over - a chair, and distinctly felt the coin drop towards the glottis; - whilst raising himself a violent fit of coughing came on, which - ceased after a few minutes. He repeated this a second time, with - the same results. A consultation was held on the 22nd, at which it - was decided that conclusive evidence existed of the half-sovereign - having passed into the windpipe, that it was probably lodged at the - bottom of the right bronchus, and that it was movable. It was - determined that every effort should be made for its removal, and - that for this purpose an apparatus should be constructed for - inverting the body of the patient, in order that the weight of the - coin might assist the natural effort to expel it by coughing. The - first experiment was made on the 25th. The body of the patient - being inverted, and the back gently struck with the hand between - the shoulders, violent cough came on, but of so convulsive and - alarming a nature that danger was apprehended, and the experiment - was discontinued. On this occasion the coin was again moved from - its situation, and slipped towards the glottis. On the 27th - tracheotomy was performed by Sir B. Brodie, assisted by Mr. Aston - Key, with the intention of extracting the coin by the forceps, if - possible, or, in the event of this failing, with the expectation - that the opening in the windpipe would facilitate a repetition of - the experiment of the 22nd. On this occasion, and subsequently on - May 2, the introduction of the forceps was attended with so much - irritation, that it could not be persevered in without danger to - life. On the 3rd another consultation was held, when Mr. Lawrence - and Mr. Stanley entirely confirmed the views of Sir B. Brodie and - Mr. Key, and it was agreed that the experiment of inversion should - be repeated as soon as Mr. Brunel had recovered sufficient - strength, the incision in the windpipe being kept open. On - Saturday, the 13th, Mr. Brunel was again placed on the apparatus, - the body inverted, and the back gently struck. After two or three - coughs, he felt the coin quit its place on the right side of the - chest, and in a few seconds it dropped from his mouth without - exciting in its passage through the glottis any distress or - inconvenience, the opening in the windpipe preventing any spasmodic - action of the glottis. - - In this remarkable case the following circumstances appear to be - worthy of note--that a piece of gold remained in the air-tube for - six weeks, quite movable, and without exciting any inflammatory - action, the breathing entirely undisturbed, and the only symptoms - of its presence occasional uneasiness on the right side of the - chest and frequent fits of coughing; that an accurate diagnosis was - formed without being able to obtain any assistance from the - stethoscope, although the chest was repeatedly and carefully - examined; and also that, a fair trial having been given to the - forceps, the application of this instrument to the removal of a - body of this peculiar form from the bottom of the bronchus was - proved to be attended with great risk to life, while the cautious - and well-considered plan of treatment above detailed was attended - with complete success, and without risk. - -During the time that Mr. Brunel was in danger the public excitement was -intense. His high professional position, the extraordinary nature of the -accident, and the greatness of the loss, were the result to prove fatal, -made his condition and the chances of his recovery an engrossing topic -of conversation; and, when the news was spread that 'it is out,' the -message needed no explanation. - -That the result was successful was due, not only to the skill of the -surgeons engaged, and to the anxious care with which those who nursed -him left nothing undone to ensure his safety, but also to the remarkable -coolness which Mr. Brunel himself displayed throughout. From the first -he took part in the consultations which were held on his case, and -assisted materially in determining the course of treatment which should -be pursued. - - * * * * * - -The ten years which followed were the most prosperous in Mr. Brunel's -life; he had attained to great eminence in his profession, and was still -in the enjoyment of robust health. But the results of the gauge -controversy and the fierce contests which followed it, and, above all, -the failure of the Atmospheric System on the South Devon Railway, caused -him grave anxiety and sorrow. Critics have erred greatly in representing -him as a man who, in order to accomplish some vast design, thought but -little of the distress which follows want of success in commercial -enterprises. So far from its being true that Mr. Brunel was indifferent -to the interests of his employers, his private journals show that -throughout (to use his own words) 'the incessant warfare in which he was -engaged' he was earnestly desiring peace and endeavouring to secure it, -and that in times of difficulty, such as the trial of the Atmospheric -System and the launch of the 'Great Eastern,' his chief thoughts were -for those who would suffer through the failure of his plans. - - * * * * * - -In the midst of his professional occupations he was able occasionally, -though rarely, to enjoy the society of his friends. After the session -was over, in 1844 and 1845, he went to Italy on business, and in 1846 to -Switzerland for a short holiday. In 1847 the South Devon Railway was -occupying his attention, and he determined to take a house at Torquay. -While there, the important character of his railway works in Devonshire -and Cornwall led him to think of making a more permanent settlement in -that part of the country. - -After a good deal of hesitation between various places, he fixed upon a -spot at Watcombe, about three miles from Torquay, on the Teignmouth -turnpike road. He made his first purchase of land in the autumn of 1847; -and from that time to within a year of his death the improvement of this -property was his chief delight. - -He had always a great love and appreciation of beautiful scenery, and in -his choice of a place in which to plant and build he provided amply for -his complete gratification. - -The principal view, which, if the house had been built, would have been -the view from the terrace, is one of the loveliest in that part of -Devonshire. On one side is the sea, and on the other the range of -Dartmoor, while in front is spread undulating country, bounded by the -hills on the further side of Torbay, the bay itself looking like a lake, -being shut in by the hills above Torquay. - -When Mr. Brunel bought this property it consisted of fields divided by -hedgerows; but, assisted by Mr. William Nesfield, he laid it out in -plantations of choice trees. The occupation of arranging them gave him -unfailing pleasure; and, although he could seldom spare more than a few -days' holiday at a time, there can be little doubt that the happiest -hours of his life were spent in walking about in the gardens with his -wife and children, and discussing the condition and prospects of his -favourite trees.[193] - -He could not, of course, take a prominent part in the affairs of the -parish, but he was always ready to assist in any work that had been -taken in hand. He will be long remembered there by his friends in every -rank of life. - -In purchasing this property in Devonshire, Mr. Brunel had looked forward -to retiring gradually from active professional life, 'to draw in and -make room for others,' and to spend a greater portion of his time in the -country. - -It may well be questioned whether he would have been happy in giving up -work while yet in middle life; but the wisdom of his resolve was not to -be put to the test. - -From the beginning of the year 1852 the 'Great Eastern' steam-ship began -to occupy his time and thoughts. As the works progressed he was more and -more tied to London; and the large pecuniary investment he had made in -the shares of the company caused him to hesitate before proceeding with -the building of his house. - -Thus the hopes he had formed for making his home in Devonshire faded -gradually away, and were at length extinguished by the failure of his -health. - - * * * * * - -Many things had happened in the earlier part of 1857 which gave him -pleasure. In June he received, in company with Mr. Robert Stephenson, -the honorary degree of Doctor in Civil Law from the University of -Oxford.[194] In the summer he paid several visits to Devonshire, and at -the beginning of September the floating of the first truss of the -Saltash bridge was successfully accomplished. - -The history of the launch of the 'Great Eastern,' which was commenced in -November, has been already told. Throughout all the disappointments he -then endured Mr. Brunel took comfort from the sympathy of valued -friends, and from those higher sources of consolation on which it was -his habit to rely. He paid for his exertions a heavy price, for they -left him broken in health and already suffering from the disease of -which in a little more than eighteen mouths afterwards he died.[195] - - * * * * * - -In May 1858 Mr. Brunel went to Vichy, and thence to Switzerland, -returning home in the autumn by way of Holland. When at Lucerne he went -up the Righi, and was so charmed with it that, instead of spending only -a night there, he remained a week, working at the designs for the -Eastern Bengal Railway. - -It was on his return to England in September that the alarming nature of -his illness was ascertained. After anxious consultation with Sir -Benjamin Brodie and Dr. Bright, he was ordered to spend the winter in -Egypt, in the hope that he might return in the March or April following -in restored health. - -He was very unwilling to be so long absent from England, especially as a -new company had just been formed to finish the 'Great Eastern,' and the -contracts for her completion were about to be let. - -However, it was thought that very serious consequences might follow if -he remained at home; and in the beginning of December he left for -Alexandria, with his wife and younger son. - -Having stayed there a day or two, they went on to Cairo, where they -found Mr. Robert Stephenson. He and Mr. Brunel dined together on -Christmas Day. - -On December 30 the journey up the Nile commenced. On January 21 they -arrived at Thebes, and spent some days there. Mr. Brunel was able to -ride about on a donkey, and made some sketches of the celebrated ruins -in the neighbourhood.[196] - -They reached Assouan on February 2, and made preparations for ascending -the cataracts. They went as far as Dakkeh, and got back to Assouan on -February 19. - -The following letter from Mr. Brunel to his sister, Lady Hawes, -describes some of the scenes through which he passed:-- - - - Philae, February 12, 1859. - - I now write to you from a charming place; but Assouan, which I - left to come here, is also beautiful, and I will speak of that - first. It is strange that so little is said in the guide books of - the picturesque beauty of these places. Approaching Assouan, you - glide through a reef of rocks, large boulders of granite polished - by the action of the water charged with sand. You arrive at a - charming bay or lake of perfectly still water and studded with - these singular jet-black or red rock islands. In the distance you - see a continuation of the river, with distant islands shut in by - mountains, of beautiful colours, some a lilac sandstone, some the - bright red yellow of the sands of the desert. Above the - promontories the water excursions are delicious. You enter at once - among the islands of the Cataracts, fantastic forms of granite - heaps of boulders split and worn into singular shapes. - - After spending a week at Assouan, with a trip by land to Philae, I - was so charmed with the appearance of the Cataracts as seen from - the shore, and with the deliciously quiet repose of Philae, that I - determined to get a boat, and sleep a few nights there. We - succeeded in hiring a country boat laden with dates, and emptied - her, and fitted up her three cabins.[197] We put our cook and - dragoman and provisions, &c., on board, and some men, and went up - the Cataract. It was a most amusing affair, and most beautiful and - curious scenery all the way. It is a long rapid of three miles, and - perhaps one mile wide, full of rocky islands and isolated rocks. A - bird's-eye view hardly shows a free passage, and some of the more - rapid falls are between rocks not forty feet wide--in appearance - not twenty. Although they do not drag the boats up perpendicular - falls of three or four feet, as the travellers' books tell you, - they really do drag the boats up rushes of water which, until I had - seen it, and had then calculated the power required, I should - imprudently have said could not be effected. We were dragged up at - one place a gush of water, what might fairly be called a fall of - about three feet, the water rushing past very formidably, and - between rocks seemingly not more than wide enough to let our boat - pass, and this only by some thirty-five men at three or four ropes, - the men standing in the water and on the rocks in all directions, - shouting, plunging into the water, swimming across the top or - bottom of the fall, just as they wanted, then getting under the - boat to push it off rocks, all with an immense expenditure of noise - and apparent confusion and want of plan, yet on the whole properly - and successfully. We were probably twenty or thirty minutes getting - up this one, sometimes bumping hard on one rock, sometimes on - another, and jammed hard first on one side and then on the other, - the boat all the time on the fall with ropes all strained, - sometimes going up a foot or two, sometimes losing it, till at last - we crept to the top, and sailed quietly on in a perfectly smooth - lake. These efforts up the different falls had been going on for - nearly eight hours, and the relief from noise was delicious. We - selected a quiet spot under the temples of Philae.... Our - poultry-yard is on the sandbank, where fowls, pigeons, and turkeys - are walking about loose, and, like all animals in this country, - perfectly tame. Yes, they walk up and catch a pigeon to be killed - when you like. In the midst of these and of the small birds which - always walk and fly about us, have been walking for hours this - morning three or four large eagles, who, with the politeness - peculiar to animals here, pay no attention to our fowls, nor do - they to the eagles. But here I am entering on the anomalies and - contradictions of Egypt, which would fill volumes. - -After leaving Egypt, Mr. Brunel went to Naples and Rome, where he spent -Easter, and he returned to England in the middle of May. - -When abroad, Mr. Brunel made sight-seeing a pleasure rather than a -business; thus in Egypt he preferred to visit frequently the same -places, and rather to enjoy that which he knew gave him pleasure, than -to hurry about with the object of seeing all that was to be seen. At -Philae he stopped more than a week, and at Thebes he spent more time in a -small outlying temple near Karnac than in the great ruin itself. So also -at Rome he went frequently to the Colosseum, and he spent many hours in -the interior of St. Peter's. - -Shortly after his return to England he went to Plymouth, and over the -Saltash bridge and other parts of the Cornwall Railway, which had been -opened during his absence abroad. - -Although it had by this time become certain that the disease under which -he laboured had assumed a fatal character, he continued to give -unremitting attention to his various professional duties; and in order -to be nearer the 'Great Eastern,' he took a house at Sydenham, and -removed there with his family in the beginning of August. - -Almost every day he went to the great ship and superintended the -preparations for getting her to sea. She was advertised to sail on -September 6, and Mr. Brunel had intended going round in her to Weymouth. - -He was on board early on the morning of the 5th, and his memorandum book -has, under that date, an entry of some unfinished work which had to be -looked after. Towards midday he felt symptoms of failing power, and went -home to his house in Duke Street, when it became evident that he had -been attacked with paralysis. - - * * * * * - -At one time it seemed possible that he might recover; but on the tenth -day after his seizure, Thursday, September 15, all hope was taken away. -In the afternoon he spoke to those who watched around him, calling them -to him by their names; as evening closed in he gradually sank, and died -at half-past ten, quietly and without pain. - - * * * * * - -The funeral was on September 20, at the Kensal Green Cemetery. - -Along the road leading to the chapel many hundreds of his private and -professional friends, his neighbours among the tradespeople of -Westminster, the Council of the Institution of Civil Engineers, and the -servants of the Great Western Railway Company, had assembled, and, with -his family, followed his body to its place of burial, in the grave of -his father and mother.[198] - -It would be improper here to attempt to enter into a general criticism -of Mr. Brunel's works, or to determine the position which he is entitled -to occupy among civil engineers. That task has yet to be accomplished, -and must be undertaken by those who can claim to be impartial judges. It -has been the object of this book to provide, as far as possible, the -materials on which a just judgment of his career can be based. - -But it may be permitted, in conclusion, to place on record the following -testimony to the high position held by Mr. Brunel in the esteem of his -contemporaries. - - * * * * * - -On November 8, 1859, at the first meeting of the Institution of Civil -Engineers after the death of Mr. Brunel and of Mr. Robert Stephenson, -Mr. Joseph Locke, M.P., the President, rose and said-- - -'I cannot permit the occasion of opening a new session to pass without -alluding to the irreparable loss which the Institution has sustained by -the death, during the recess, of its two most honoured and distinguished -members. - -'In the midst of difficulties of no ordinary kind, with an ardour -rarely equalled, and an application both of body and mind almost beyond -the limit of physical endurance, in the full pursuit of a great and -cherished idea, Brunel was suddenly struck down, before he had -accomplished the task which his daring genius had set before him. - -'Following in the footsteps of his distinguished parent, Sir Isambard -Brunel, his early career, even from its commencement, was remarkable for -originality in the conception of the works confided to him. As his -experience increased, his confidence in his own powers augmented; and -the Great Western Railway, with its broad-gauge line, colossal engines, -large carriages, and bold designs of every description, was carried -onward, and ultimately embraced a wide district of the country. - -'The same feeling induced, in steam navigation, the successive -construction of the "Great Western" steamer, the largest vessel of the -time, until superseded by the "Great Britain," which was in its turn -eclipsed by the "Great Eastern," the most gigantic experiment of the -age. - -'The Great Ship was Brunel's peculiar child; he applied himself to it in -a manner which could not fail to command respect; and, if he did not -live to see its final and successful completion, he saw enough, in his -later hours, to sustain him in the belief that his idea would ultimately -become a triumphant reality. - -'The shock which the loss of Brunel created was yet felt, when we were -startled by an announcement that another of our esteemed members had -been summoned from us.[199] - - * * * * * - -'It is not my intention at this time to give even an outline of the -works achieved by our two departed friends. Their lives and labours, -however, are before us; and it will be our own fault if we fail to draw -from them useful lessons for our own guidance. Man is not perfect, and -it is not to be expected that he should be always successful; and, as in -the midst of success we sometimes learn great truths before unknown to -us, so also we often discover in failure the causes which frustrate our -best directed efforts. Our two friends may probably form no exception to -the general rule; but, judging by the position they had each secured, -and by the universal respect and sympathy which the public has -manifested for their loss, and remembering the brilliant ingenuity of -argument, as well as the more homely appeals to their own long -experience, often heard in this hall, we are well assured that they have -not laboured in vain. - -'We, at least, who are benefited by their successes, who feel that our -Institution has reason to be proud of its association with such names as -Brunel and Stephenson, have a duty to perform; and that duty is, to -honour their memory and emulate their example.' - - - - -APPENDIX I. - -(_See Chapter V. on the Broad Gauge, p. 99._) - - -_Report to the Board of Directors of the Great Western Railway Company._ - - August 1838. - -GENTLEMEN,--As the endeavour to obtain the opinions and reports of Mr. -Walker, Mr. Stephenson, and Mr. Wood, prior to the next half-yearly -meeting, has not been successful, I am anxious to record more fully than -I have previously done, and to combine them into one report, my own -views and opinions upon the success of the several plans which have been -adopted at my recommendation in the formation and in the working of our -line; and in justice to myself and to these plans, and indeed to enable -others to arrive at any just conclusion as to the result which has been -attained, or as to the probable ultimate success or advantages of the -system, it is necessary that I should enter very fully, I fear even -tediously, into a recapitulation of the circumstances, peculiar to this -railway, which led to the consideration and the adoption of these plans, -which some call innovations and wide deviations from the results of past -experience, but the majority of which I will undertake to show are -merely adaptations of those plans to our particular circumstances. - -It will be necessary also that I should refer to all the numerous -difficulties which we have had to encounter, which have necessarily -prevented the perfect working of these plans in the first instance, but -which have been overcome, or which are gradually and successively -diminishing; and, finally, I am prepared to show that, notwithstanding -the novelty of the circumstances, and the difficulties and delays which -at the outset invariably attend any alteration, however necessary, or -however desirable, from the accustomed mode of proceeding, and -notwithstanding the violent prejudices excited against us, and the -increased difficulties caused by these prejudices, the result is still -such as to justify the attempt which has been made, and to show that in -the main features, if not in all the details, the system hitherto -followed is good, and ought to be pursued. - -The peculiarity of the circumstances of this railway, to which I would -more particularly refer, and which have frequently been mentioned, -consists in the unusually favourable gradients and curves which we have -been able to obtain. With the capability of carrying the line upwards of -fifty miles out of London on almost a dead level, and without any -objectionable curve, and having beyond this, and for the whole distance -to Bristol, excellent gradients, it was thought that unusually high -speed might easily be attained, and that the very large extent of -passenger traffic which such a line would certainly command would ensure -a return for any advantages which could be offered to the public, either -in increased speed or increased accommodations. With this view every -possible attention was paid to the improvement of the line as originally -laid down in the parliamentary plans. We ultimately succeeded in -determining a maximum gradient of 4 feet per mile, which could be -maintained for the unusual distance, before mentioned, of upwards of -fifty miles from London, and also between Bristol and Bath, -comprehending those parts of the line on which the principal portion of -the passenger traffic will be carried. The attainment of high speed -appeared to involve the question of the width of gauge, and on this -point accordingly I expressed my opinion at a very early period. - -It has been asserted that 4 feet 8 inches, the width adopted on the -Liverpool and Manchester Railway, is exactly the proper width for all -railways, and that to adopt any other dimension is to deviate from a -positive rule which experience has proved correct; but such an assertion -can be maintained by no reasoning. Admitting, for the sake of argument, -that, under the particular circumstances in which it has been tried, 4 -feet 8 inches has been proved the best possible dimension, the question -would still remain--What are the best dimensions under the -circumstances? - -Although a breadth of 4 feet 8 inches has been found to create a certain -resistance on curves of a certain radius, a greater breadth would -produce only the same resistance on curves of greater radius. If -carriages and engines, and more particularly if wheels and axles of a -certain weight, have not been found inconvenient upon one railway, -greater weights may be employed and the same results obtained on a -railway with better gradients. To adopt a gauge of the same number of -inches on the Great Western Railway as on the Grand Junction Railway, -would in fact amount practically to the use of a different gauge in -similar railways. The gauge which is well adapted to the one is not well -adapted to the other, unless, indeed, some mysterious cause exists which -has never yet been explained for the empirical law which would fix the -gauge under all circumstances. - -Fortunately this no longer requires to be argued, as too many -authorities may now be quoted in support of a very considerable -deviation from this prescribed width, and in every case this change has -been an increase. I take it for granted that, in determining the -dimensions in each case, due regard has been had to the curves and -gradients of the line, which ought to form a most essential, if not the -principal, condition. - -In the Report of the Commissioners upon Irish Railways, the arguments -are identically the same with those which I used when first addressing -you on the subject in my Report of October 1835. The mechanical -advantage to be gained by increasing the diameter of the carriage-wheels -is pointed out, the necessity, to attain this, of increasing the width -of way, the dimensions of the bridges, tunnels, and other principal -works, not being materially affected by this; but, on the other hand, -the circumstance which limits this increase being the curves on the -line, and the increased proportional resistance on inclinations (and on -this account it is stated to be almost solely applicable to very level -lines); and, lastly, the increased expense, which could be justified -only by a great traffic. - -The whole is clearly argued in a general point of view, and then applied -to the particular case, and the result of this application is the -recommendation of the adoption of 6 feet 2 inches on the Irish railways. -Thus, an increase in the breadth of way to attain one particular -object--viz. the capability of increasing the diameter of the -carriage-wheels without raising the bodies of the carriages--is admitted -to be most desirable, but is limited by certain circumstances, namely, -the gradients and curves of the line, and the extent of traffic. - -Every argument here adduced, and every calculation made, would tend to -the adoption of about 7 feet on the Great Western Railway. - -The gradients of the lines laid down by the Irish Commission are -considerably steeper than those of the London and Birmingham Railway, -and four and five times the inclination of those on the Great Western -Railway; the curves are by no means of very large radius, and indeed the -Commissioners, after fixing the gauge of 6 feet 2 inches, express their -opinion, that upon examination into the question of curves, with a view -to economy, they do not find that the effect is so injurious as might -have been anticipated, and imply therefore that curves, generally -considered of small radius on our English lines, are not incompatible -with the 6 feet 2 inch gauge; and, lastly, the traffic, instead of being -unusually large, so as to justify any expense beyond that absolutely -required, is such as to render assistance from Government necessary to -ensure a return for the capital embarked. As compared with this, what -are the circumstances in our case? - -The object to be attained is the placing an ordinary coach body, which -is upwards of 6 feet 6 inches in width, between the wheels. This -necessarily involves a gauge of rail of about 6 feet 10-1/2 inches to 6 -feet 11 inches, but 7 feet allows of its being done easily; it allows, -moreover, of a different arrangement of the body: it admits all sorts of -carriages, stage-coaches, and carts to be carried between the wheels. -And what are the limits in the case of the Great Western Railway, as -compared to those on Irish railways? Gradients of one-fifth the -inclination, very favourable curves, and probably the largest traffic in -England. - -I think it unnecessary to say another word to show that the Irish -Commissioners would have arrived at 7 feet on the Great Western Railway -by exactly the same train of argument that led them to adopt 6 feet 2 -inches in the case then before them. - -All these arguments were advanced by me in my first Report to you, and -the subject was well considered. The circumstance of the Great Western -Railway, and other principal railways likely to extend beyond it, having -no connection with other lines then made, leaving us free from any -prescribed dimension, the 7-feet gauge was ultimately determined upon. -Many objections were certainly urged against it: the deviation from the -established 4 feet 8 inches was then considered as the abandonment of -the principle: this, however, was a mere assertion, unsupported even by -plausible argument, and was gradually disused; but objections were still -urged, that the original cost of construction of all the works connected -with the formation of the line must be greatly increased; that the -carriages must be so much stronger; that they would be proportionally -heavier; that they would not run round the curves, and would be more -liable to run off the rails; and particularly, that the increased length -of the axles would render them liable to be broken: and these objections -were not advanced as difficulties which, as existing in all railways, -might be somewhat increased by the increase of gauge, but as peculiar to -this, and fatal to the system. - -With regard to the first objection, namely, the increased cost in the -original construction of the line, if there be any, it is a question of -calculation which is easily estimated, and was so estimated before the -increased gauge was determined upon. Here, however, preconceived -opinions have been allowed weight in lieu of arguments and calculations; -cause and effect are mixed up, and without much consideration it was -assumed at once that an increased gauge necessarily involved increased -width of way, and dimensions of bridges, tunnels, &c. - -Yet such is not the case within the limits we are now treating of: a -7-feet rail requires no wider bridge or tunnel than a 5-feet; the -breadth is governed by a maximum width allowed for a loaded waggon, or -the largest load to be carried on the railway, and the clear space to be -allowed on either side beyond this. - -On the Manchester and Liverpool Railway this total breadth is only 9 -feet 10 inches, and the bridge and viaducts need only have been twice -this, or 19 feet 8 inches; 9 feet 10 inches was found, however, rather -too small, and in the London and Birmingham, with the same width of way, -this was increased to 11 feet by widening the interval between the two -rails. - -In the space of 11 feet, allowed for each rail, a 7-feet gauge might be -placed just as well as a 5-feet, leaving the bridges, tunnels, and -viaducts exactly the same; but 11 feet was thought by some still too -narrow: and when it is remembered that this barely allows a width of 10 -feet for loads, whether of cotton, wool, agricultural produce, or other -light goods, and which are liable also to be displaced in travelling, 13 -feet (which has been fixed upon in the Great Western Railway, and which -limits the maximum breadth, under any circumstances, to about 12 feet) -will not be found excessive. - -It is this which makes the minimum width, actually required under -bridges and tunnels, 26 feet instead of 22 feet, and not the increased -gauge. - -The earthwork is slightly affected by the gauge, but only to the extent -of 2 feet on the embankment, and not quite so much in the cuttings; but -what, in practice, has been the result? The bridges over the railway on -the London and Birmingham are 30 feet, and the width of viaducts 28 -feet; on the Great Western Railway they are both 30 feet; no great -expense is therefore incurred on these items, and certainly a very small -one compared to the increased space gained, which, as I have stated, is -from 10 to 12 feet. In the tunnels exists the greatest difference; on -the London and Birmingham Railway, which I refer to as being the best -and most analogous case to that of the Great Western Railway, the -tunnels are 24 feet wide. On the Great Western Railway the constant -width of 30 feet is maintained, more with a view of diminishing the -objections to tunnels, and maintaining the same minimum space which -hereafter may form a limit to the size and form of everything carried on -the railway, than from such a width being absolutely necessary. - -Without pretending to find fault with the dimensions fixed, and which -have, no doubt, been well considered, upon the works on other lines, I -may state that the principle which has governed has been to fix the -minimum width, and to make all the works the same, considering it -unnecessary to have a greater width between the parapet walls of a -viaduct, which admits of being altered, than between the sides of a -tunnel which cannot be altered. - -The embankments on the London and Birmingham Railway are 26 feet, on the -Great Western 30 feet, making an excess of about six and a half per -cent. on the actual quantity of earthwork. - -The difference in the quantity of land required is under half an acre to -a mile. On the whole, the increased dimensions from 10 to 12 feet will -not cause any average increased expense in the construction of the -works, and purchase of land, of above seven per cent.--eight per cent. -having originally been assumed in my Report in 1835 as the excess to be -provided for. - -With respect to the weight of the carriages, although we have wheels of -4 feet diameter, instead of 3 feet, which, of course, involves an -increased weight quite independent of the increase of width, and -although the space allowed for each passenger is a trifle more, and the -height of the body greater, yet the gross weight per passenger is -somewhat less. - - Tons cwt. qrs. lbs. - - A Birmingham first-class coach weighs 3 17 2 0 - Which with 18 passengers at 15 to the ton 1 4 0 0 - ---------------- - 5 1 2 0 - Or 631 lbs. per passenger ================ - - A Great Western first-class weighs 4 14 0 0 - And with 24 passengers 1 12 0 0 - ---------------- - 6 6 0 0 - Or 588 lbs. per passenger ================ - - And our 6-wheeled first-class 6 11 0 0 - With 32 passengers 2 2 2 0 - ---------------- - 8 13 2 0 - Or 600 lbs. per passenger ================ - -Being an average of 594 lbs. on the two carriages. - -This saving of weight does not arise from the increased width, and is -notwithstanding the increased strength of the framing and the increased -diameter and weight of the wheels; I have not weighed our second-class -open carriages, but I should think the same proportion would exist. - -As to the breaking of axles or running off the line, the practical -result has been that, from some cause or other, we have been almost -perfectly free from those very objections which have been felt so -seriously on some other lines. Far from breaking any engine axles, not -even a single cranked axle has been strained, although the engines have -been subjected to rather severe trials. One of our largest having, a -short time back, been sent along the line at night, when it was not -expected, came in collision with some ballast waggons, and was thrown -off the line nearly 6 feet; none of the axles were bent, or even -strained in the least, although the front of the carriage, a piece of -oak of very large scantling, was shattered. After ten weeks' running, -one solitary instance has occurred of a carriage in a train getting off -the line and dragging another with it, and which was not discovered till -after running a mile and a half. As the carriage was in the middle of -the train, and one end of the axle was thrown completely out of the axle -guard, there must evidently have been some extraordinary cause--possibly -a plank thrown across the railway by a blow from the carriage which -preceded, and which might have produced the same effect on any railway; -and at any rate it was a strong trial to the axle, which was not broken, -but merely restored to its place, and the carriage sent on to London. -The same mode of reasoning which has by some been used in favour of the -4 feet 8 inches gauge, if applied here, would prove that long axles are -stronger than short, and wide rails best adapted for curves. All that I -think proved, however, is this--that the increased tendency of the axles -to break, or of the wheels to run off the rails, is so slight that it is -more than counterbalanced by the increased steadiness from the width of -the base, and the absence of those violent strains which arise from -irregularity on the gauge and the harshness of the ordinary construction -of rails. In fact, not one of the objections originally urged against -the practical working of the wide gauge has been found to exist, while -the object sought for is obtained, namely, the capability of increasing -at any future period the diameter of the wheels, which cannot be done, -however desirable it may hereafter be found, with the old width of rail. -This may be said to be only prospective; but, in the meantime, -contingent advantages are sensibly felt in the increased lateral -steadiness of the carriages and engines, and the greater space which is -afforded for the works of the locomotives. And here I wish particularly -to call your attention to the fact that this prospective advantage--this -absence of a most inconvenient limit to the reduction of the friction, -which, with our gradients, forms four-fifths or eighty per cent. of the -total resistance--was the object sought for, and that, at the time of -recommending it, I expressly stated as follows:--'I am not by any means -prepared at present to recommend any particular size of wheel, or even -any great increase of the present dimensions. I believe they _will_ be -materially increased; but my great object would be in every possible way -to render each part _capable_ of improvement, and to remove what appears -an obstacle to any great progress in such a very important point as the -diameter of the wheels, upon which the resistance, which governs the -cost of transport and the speed that may be obtained, so materially -depends.' - -These advantages were considered important by you, they are now -considered so by many others; and certainly everything which has -occurred in the practical working of the line confirms me in my -conviction that we have secured a most valuable power to the Great -Western Railway, and that it would be folly to abandon it. - -The next point I shall consider is the construction of the engines, the -modifications in which, necessary to adapt them to higher speeds than -usual, have, like the increased width of gauge, been condemned as -innovations. - -I shall not attempt to argue with those who consider any increase of -speed unnecessary. The public will always prefer that conveyance which -is most perfect, and speed within reasonable limits is a material -ingredient in perfection in travelling. - -A rate of thirty-five to forty miles an hour is not unfrequently -attained at present on other railways in descending planes, or with -light loads on a level, and is found practically to be attended with no -inconvenience. To maintain such a speed with regularity on a level line, -with moderate loads, is therefore quite practicable, and unquestionably -desirable. With this view the engines were constructed, but nothing new -was required or recommended by me. - -A certain velocity of the piston is considered the most advantageous. - -The engines intended for slow speeds have always had the driving wheels -small in proportion to the length of stroke of the piston. The faster -engines have had a different proportion; the wheels have been larger, or -the strokes of the piston shorter. From the somewhat clamorous -objections raised against the large wheels, and the construction of the -Great Western Railway engines, and the opinions rather freely expressed -of my judgment in directing this construction, it would naturally be -supposed that some established principle had been departed from, and -that I had recommended this departure. - -The facts are, that a certain velocity of piston being found most -advantageous, I fixed this velocity, so that the engines should be -adapted to run thirty-five miles an hour, and capable of running -forty--as the Manchester and Liverpool Railway engines are best -calculated for twenty to twenty-five, but capable of running easily up -to thirty and thirty-five miles per hour; and fixing also the load which -the engine was to be capable of drawing, I left the form of construction -and the proportions entirely to the manufacturers, stipulating merely -that they should submit detail drawings to me for my approval. This was -the substance of the circular, which, with your sanction, was sent to -several of the most experienced manufacturers. Most of these -manufacturers, of their own accord, and without previous communication -with me, adopted the large wheels, as a necessary consequence of the -speed required. The recommendation coming from such quarters, there can -be no necessity for defending my opinion in its favour; neither have I -now the slightest doubt of its correctness. As it has been supposed that -the manufacturers may have been compelled or induced by me to adopt -certain modes of construction, or certain dimensions, in other parts by -a specification--a practice which has been adopted on some lines--and -that these restrictions may have embarrassed them, I should wish to take -this opportunity to state distinctly that such is not the case. I have -indeed strongly recommended to their consideration the advantages of -having very large and well-formed steam passages, which generally they -have adopted, and with good results; and with this single exception, if -it can be considered one, they have been left unfettered by me (perhaps -too much so) and uninfluenced, except indeed by the prejudices and fears -of those by whom they have been surrounded, which have by no means -diminished the difficulties I have had to contend with. - -The principal proportions of these engines being those which have been -recommended by the most able experimentalists and writers, and these -having been adopted by the most experienced makers, it is difficult to -understand who can constitute themselves objectors, or what can be their -objections. - -Even if these engines had not been found effective, at least it must be -admitted that the best and most liberal means had been adopted to -procure them; but I am far from asking such an admission. The engines, -I think, have proved to be well adapted to the particular task for which -they were calculated--namely, high speeds--but circumstances prevent -their being beneficially applied to this purpose at present, and they -are, therefore, working under great disadvantages. An engine constructed -expressly for a high velocity cannot, of course, be well adapted to -exert great power at a low speed; neither can it be well adapted for -stopping frequently and regaining its speed. But such was not the -intention when these engines were made, neither will it be the case when -the arrangements on the line are complete; in the meantime, our average -rate of travelling is much greater than it was either on the Grand -Junction or the Birmingham Railway within the same period of the -opening. I have but one serious objection to make to our present -engines, and for this, strange as it may seem, I feel that we are mainly -indebted to those who have been most loud in their complaints--I refer -to the unnecessary weight of the engines. There is nothing in the wide -gauge which involves any considerable increased weight in the engine. An -engine of the same power and capacity for speed, whether for a 4-feet -8-inch rail, or for a 7-feet rail, will have identically the same -boiler, the same fire-box, the same cylinder and piston, and other -working gear, the same side frames, and the same wheels; the axles and -the cross-framing will alone differ, and upon these alone need there be -any increase; but, if these were doubled in weight, the difference upon -the whole engine would be immaterial. But the repeated assertion, -frequently professing to come from experienced authorities, and repeated -until it was supposed to be proved, that the increased gauge must -require increased strength and great power, was not without its indirect -effect upon the manufacturers. Unnecessary dimensions have been given to -many parts, and the weight thereby increased--rather tending, as I -believe, to diminish than to add to the strength of the whole. I thought -then, and I believe now, that it would have been unwise in this case to -have resisted the general opinion, and taken upon myself the -responsibility which belonged to the manufacturers; but I need not now -hesitate to say that a very considerable reduction may be effected, and -that no such unusual precautions are necessary to meet these anticipated -strains and resistances--such being, in fact, imaginary. It cannot -surprise anybody that, under such circumstances, attention was more -occupied in endeavouring to meet these imaginary prejudiced objections, -than in boldly taking advantage of the new circumstances, and that a -piece of machinery constructed under such disadvantages was not likely -to be a fair sample of what might be done. I am happy to say, however, -that the result of the trials that have been made has entirely destroyed -all credit in these alarmists with the manufacturer, and that we may -hope in future to have the benefits of the free exercise of the -intelligence and practical knowledge of engine-manufacturers. - -The mode of laying the rails is the next point which I shall consider. -It may appear strange that I should again in this case disclaim having -attempted anything perfectly new; yet regard to truth compels me to do -so. I have recommended, in the case of the Great Western, the principle -of a continuous bearing of timber under the rail, instead of isolated -supports--an old system recently revived, and as such I described it in -my Report of January 1836; the result of many hundred miles laid in this -manner in America, and of some detached portions of railways in England, -was quite sufficient to prove that the system was attended with many -advantages; but since we first adopted it these proofs have been -multiplied--there need now be no apprehension. There are railways in -full work, upon which the experiment has been tried sufficiently to -prove beyond doubt, to those willing to be convinced, that a permanent -way in continuous bearings of wood may be constructed, in which the -motion will be much smoother, the noise less, and consequently--for they -are effects produced by the same cause--the wear and tear of the -machinery much less. Such a plan is certainly best adapted for high -speeds, and this is the system recommended by me and adopted on our -road. There are, no doubt, different modes of construction, and that -which I have adopted as an improvement upon others may, on the contrary, -be attended with disadvantages. For the system I will strenuously -contend. - -But I should be sorry to enter with any such determined feeling into a -discussion of the merits of the particular mode of construction. I would -refer to my last Report for the reasons which influenced me, and the -objects I had in view in introducing the piling; that part which had -been made under my own eye answered fully all my expectations. Here the -piles did answer their purpose, and no inconvenience resulted from their -use. The difficulties which we have since encountered, the bad state in -which the line was for a considerable time, and which is only recently -improved, have undoubtedly been aggravated, if not caused, by these -piles; but not, as I believe, from a defect in the principle as applied -in our case, where the line is mostly in cutting, or on the surface, but -from defective execution; for, notwithstanding the determination to -allow sufficient time for this most important operation, yet, to make up -for previous delays and loss of time, it became necessary at last to -force forward the work more rapidly than was at all consistent with due -care in the execution; and during the whole of this period I was most -unfortunately prevented by a serious accident from even seeing the work -almost until the day of opening, when I ought to have personally -superintended the whole. I do not mean that the work was neglected by -those whose duty it was to supply my place--far from it; but in such a -case, a new work cannot be properly directed except under the eye of the -master. Following exactly the plan which had succeeded on the first -piece completed, several serious faults were committed. A much greater -density and firmness of packing is required than was previously -supposed; the mode of packing adopted, and the material selected, in the -first instance, have proved defective elsewhere; and over a great extent -in the line, particularly in the clay cuttings, and where the work was -at last most hurried, it has been badly executed. But many parts have -stood well from the commencement; others are fast improving; and I have -the satisfaction, although a very painful one, of seeing that if, in the -first instance, a foundation of coarse gravel had been everywhere well -rammed in before the timbers had been laid, and the packing formed upon -this, we should, from the outset, have obtained as solid a road as we -have now over a great part of the line. What we have been able to effect -since the opening of the line has necessarily been a slow, expensive, -and laborious operation. We have been compelled to open the ground, and -excavate it to a depth of 18 inches under the longitudinal timbers, and -this without interrupting the traffic: to remove the whole of the -material thus obtained from off the line, and to replace it by coarse -ballast; and not having the means of sufficiently consolidating this -ballast by ramming while the timber is in its place, the packing has to -be repeated once or twice after it has been compressed by the passing of -the trains. This new packing, however, does stand, and in a few weeks I -expect the line will be in a very different state from that in which it -has been, or indeed now is. From what I have described as the result -which can now be, and might have been, obtained from the commencement, -it will be inferred that I am disposed still to defend the system of -piling. I certainly could not abandon it from conviction of its -inefficiency, for I see proofs of the contrary; and I feel that under -similar circumstances I could now prevent the mischief which has -occurred. Upon that portion of the line where the permanent way must -next be formed, piling could not be resorted to, the ground being a -solid hard chalk for many miles. I had intended, however, recommending -the same principle, but in a different form, holding down the -longitudinals by small iron rods driven into the chalk; but the same -objection could not exist, because the chalk cannot yield under the -timbers like clay, or even gravel. But I should wish most anxiously to -avoid anything like an obstinate adherence to a plan, if the object -which I believe essential can be obtained by other means, particularly -when, that plan being my own, I may be somewhat prejudiced in its -favour. I find that the system of piling involves considerable expenses -in the first construction, and requires perhaps too great a perfection -in the whole work, and that if the whole or a part of this cost were -expended in increased scantling of timber and weight of metal, that a -very solid continuous rail would be formed. - -For this as a principle, as for the width of gauge, I am prepared to -contend, and to stand or fall by it, believing it to be a most essential -improvement, where high speeds are to be obtained. I strongly urge upon -you not to hesitate upon these two main points, which, combined with -what may be termed the natural advantages of the line, will eventually -secure to you a superiority which, under other circumstances, cannot be -obtained. - -As regards the expense of forming the permanent way on this principle, I -am quite prepared to maintain what I have on a former occasion advanced: -that even on the system which we have adopted between London and -Maidenhead, the total cost does not materially exceed that of a -well-constructed line with stone blocks. I did not make in the outset an -exact estimate of the cost of either mode; I was unable to obtain the -cost which has actually been incurred on other lines; but a comparative -estimate was made, and the result of that comparison led me to state -that the one might exceed the other by 500_l._ a mile. The actual cost -of our permanent way appears, by the detailed account which has been -made out, to have been above 9,000_l._, including expenses of -under-draining and forming the surfaces which cannot be included in the -cost given in other cases, because that drainage (although I believe -generally forming part of the plan) is not yet constructed. This sum -includes the sidings at the stations, switches, joints, and other -contingencies, and also the expenses incurred during the first month of -working the line, and which, as I have before stated, consisted in -removing and replacing work which had been improperly executed. These -items will make a considerable reduction; and besides these, larger -reductions may be effected in parts of the work which were new, and, -from the circumstances naturally attending a first attempt, were not so -economically conducted as they might be, or indeed, as they were towards -the close of the works, when the different parts were let by contract. -Taking the prices at which the work was latterly actually executed, -8,000_l._ per mile would be a liberal allowance for our future -proceeding, even adopting the same system; and with a modified system, -such as that suggested of simple longitudinal bearers of large -scantling, and a rail of fifty-four pounds per yard, at the present high -price of iron, the cost, calculated upon our actual past expenditure, -would not exceed 7,400_l._ per mile. This, I am aware, is a larger sum -than that which has usually been assumed as the cost of the permanent -way. I cannot prove that others have cost more, or even so much as this, -as I have nothing but the published accounts to refer to; but this I can -state, and prove if necessary, that rails and blocks, such as are now -being adopted on the Manchester and Liverpool Railway, would upon our -line cost at least as much. - -The prime cost of rails and chairs delivered on the line would alone -amount to half the money; and nothing is, perhaps, more certain than -that the experience of other lines within the last two or three years -has proved that this part of the construction of a railway is -unavoidably much more expensive than was ever calculated for at the time -our estimates were made. - - I am, gentlemen, your obedient servant, - - (Signed) I. K. BRUNEL. - - - - -APPENDIX II. - -(_See Chapter IX. on the 'Great Britain' Steam-Ship, p. 254._) - -_Report to the Directors of the Great Western Steam-Ship Company._ - - - October 1840. - -GENTLEMEN,--I have now the pleasure to lay before you the result of the -different experiments which I have made, and of the best consideration I -have been enabled to give to the subject of the screw propeller. - -The observations which I have to make are naturally divided under two -principal heads, namely: first, the simple question of the applicability -and efficiency of the screw considered merely as a means of propelling a -vessel, compared with the ordinary paddlewheel; and, secondly, the -general advantages or disadvantages attending its use. - -The consideration of the comparative efficiency of the screw as a means -of propelling, of course embraces the whole question, not merely of the -effect produced, but also that of the proportionate power absorbed in -producing that effect. - -With respect to the mere effect of a screw, the performance of the -'Archimedes' has proved, in a satisfactory and undeniable manner, that a -screw acting against the water with a surface even much smaller than -that offered by the paddle-boards of a well-proportioned paddlewheel, -will propel the ship at a very fair speed, but at what expense of power -this effect has been produced is not so evident. - -I shall first examine into the principal cause of what amounts -practically to a loss of power, and which is common in a greater or less -degree to all modes of propelling a vessel by exerting a pressure -against the water as against a fixed point. - -The resistance, whether to the surface of a screw, or of a paddle-board, -or of the blade of an oar, or any other propelling body, offered by the -fluid against which it acts, is of course not perfect, and there is a -certain amount of yielding, commonly called the slip, of the -paddlewheel; the amount thus slipped causes a considerable waste of -power, inasmuch as the full power of the engine is expended through the -entire space passed over by the paddles or other propelling surface, -while the useful effect produced is only equal to the same power -expended over the space through which the vessel passes: this loss -frequently amounts to one-quarter, and even one-third, of the whole -power employed. To investigate theoretically the amount of slip due to -any given form and quantity of surface, involves much more complicated -calculations than have generally been applied, and would indeed require -data which we hardly possess; but fortunately we have had the means of -making experiments, the results of which enable us to determine the -comparative slip of the paddle and of the screw, with sufficient -accuracy for all practical purposes. - -The screw in use on board the 'Archimedes' is 5 feet 9 inches diameter, -with a pitch of 8 feet--that is to say, in making one revolution the -thread of the screw advances 8 feet; the area of the screw, considered -as a disc of the same diameter, or the extent of the surface of water -which is acted upon in the direction of the axis of the vessel, is -therefore about 26 feet, without deducting the section of the -shaft-bearing, &c. The midship section of the vessel when I experimented -upon her was, according to Mr. Patterson's estimate, 122 feet; the ratio -of the resisting surface to the midship section being therefore as 1 to -4.7, which is a small proportion; and the form of the vessel is by no -means peculiarly good as a steamboat. This proportion of propelling -surface to midship section is much smaller--that is, the area of the -screw is much less in proportion to the size of the vessel than is the -area of paddle-boards immersed in steamboats generally. - -The average paddle-board immersed and really effective is rather -difficult to estimate, as allowances must be made for the disturbance of -the water, when the wheel is in motion; but this average in the 'Great -Western' measured perpendicularly--that is, allowing for the obliquity -of the paddle--cannot be less than 180 to 200 feet, say only 180, while -the midship section averages about 462 feet; the surface of paddle is -therefore about 1/2.56 of the midship section. - -I will now give the comparative effects of these different propelling -surfaces in these two cases. - -I have made very accurate experiments upon the comparative rate of the -'Archimedes,' and of the space passed through by the screw, and was -enabled to determine this ratio with great certainty. - -The average of a number of trials gave the following results: - -Rate of ship, 50,867 feet per hour, or about 8-1/3 knots. - -Space passed through by screw due to the number of revolutions, 65,685 -feet. - -The average rate of vessel being to that of screw therefore as 1 to -1.2913. - -In the performances of the 'Great Western,' upon an average of 20 -voyages the ratio has been as 1 to 1.2997; but, separating from these 20 -such voyages as were unusually short or long, and taking only such as, -occupying 14, 15, or 16 days, may be considered as giving a fair average -of the speed of the ship when not adversely affected by the wind or -heavy seas, the average of these 13 voyages give 1 to 1.283; and leaving -out again those of 16 days, and taking only 8 voyages of 14 and 15 days, -the average gives a ratio of 1 to 1.27187. - - Of these, 5 voyages of 15 days give 1 to 1.29077, - and 3 " 14 " 1 to 1.23901. - -The last three, however, were short passages and homeward, when the -currents and winds have been in favour, and consequently we may safely -say that the ratio must be above 1 to 1.239; and after making every -allowance for the effect of swell and other impediments (the experiments -upon the 'Archimedes' being made in smooth water), the average of the 8 -(5 of which were homeward voyages with favourable current and wind and -the vessel in good trim), giving a ratio of 1 to 1.27, may be taken as a -fair average. - -The comparison between the 'Archimedes' and the 'Great Western' will -therefore stand thus-- - - Area of Propelling Difference of Speed of - Surface, the Midship Vessel and Propelling - Section being 1.0. Surface, or amount - of Slip, the ratio - of Vessel being 1.0. - - 'Archimedes,' screw 0.203 0.2913 - 'Great Western,' paddle 0.391 0.2708 - -Showing an amount of slip in the 'Great Western' very nearly equal to -that of the 'Archimedes,' while the ratio of the propelling surface to -the midship section in the case of the screw is little more than half -that of the paddle-boards in the 'Great Western.' - -In taking the average of the eight voyages of the 'Great Western' with -favourable winds as I have done, I believe I have made full allowance -for the different circumstances of smooth water and sea; but there is -ample room in the above comparison to make even greater allowance for -these circumstances, and still to leave a result which would prove that -with _similar areas_ the screw would meet with at least equal, if not a -greater resistance, and consequently will slip as little or less than -the ordinary paddle-board. - -I subjoin a table also, taken from a well-known work on the steam-engine -(Tredgold's), of the slip of a number of vessels, of which in every case -the surface of paddle immersed is far greater in proportion to the -midship section than that of the screw in the 'Archimedes.' - -_Rate of Paddle, that of Ship being_ 1. - - Medea 1.595 - Flamer 1.483 - Firebrand 1.501 - Columbine 1.529 - Salamander 1.200[200] - Dee 1.366 - Firefly 1.364 - Firebrand, as altered 1.295 - Phito 1.215 - Monarch 1.323 - Magnet 1.310 - Meteor 1.490 - Carron 1.287 - Average 1.381 - - Great Western 1.27 - Archimedes 1.29 - -This list shows that the result in the 'Great Western,' with which ship -I have made the comparison, is in itself a favourable one, and that -compared with many others the 'Archimedes' would stand much better. - -This apparent superiority of the screw over the paddle as regards the -resistance offered to it by the water may at first appear startling, but -there is a great mistake committed in assuming that the action of the -screw is a very oblique action, tending rather to drive the water -laterally with a rotatory motion than to push it steadily backwards. - -Having witnessed and carefully observed the degree and the nature of the -disturbance in the water caused by the screw, and comparing this with -the violent displacement of the water by the action of paddle-boards, -even under the most favourable circumstances, I no longer feel -surprised. - -The mass of water pushed backwards by the action of the screw appears to -be very large, spreading from the screw probably in the form of an -inverted cone, but there is little or no appearance of any rotatory -motion, and the surface of the water is not put into rapid motion as in -the case of the paddlewheel, which may be observed to impart a -considerable velocity to the water, probably for a small depth only, but -over a very large space. - -As regards the oblique action also, a great mistake appears to have been -generally made, and very naturally made, by most persons when first -considering the working of the screw. It is generally assumed that the -inclined plane formed by the thread of the screw strikes the particles -of water at that angle and with the velocity of the revolution of the -screw, but it is forgotten that the screw is moving forward with the -ship, and therefore that the angle at which the water is struck by the -plane is diminished by all that much that the ship with the screw -advances--indeed, it is evident that if the ship advanced the whole -amount of the pitch of the screw, the screw, oblique as it appears, and -rapidly as it revolves, would not strike the water at all, but simply -glide through. - -The angle at which any given part of the screw does in fact strike the -water is only equal to the difference between the angle to which that -part of the screw is formed and the angle or direction in which it moves -by the compound motion of the revolution of the screw and of the forward -motion of the ship and screw; and, contrary to one's hastily imbibed -notions of the action of the screw, this angle at which the plane of the -screw is driven against the particles of water, is in such a screw as -that of the 'Archimedes' very nearly equal over the greater portion of -the surface, diminishing to nothing at the centre; and the motion -imparted to the water, although perpendicular to the plane of the screw -in point of direction, is small in extent or velocity, being also nearly -the same over the whole surface of the screw, except close to the -centre, where it is infinitely small. - -In the 'Archimedes' screw, which appears to the eye so oblique, and the -centre part of which would appear to act flat against the water, only -causing it to revolve, the outer circumference being 18 feet and the -slip 1 foot 8 inches, the angle at which this outer edge acts upon the -water is only one in 11-1/2. - -The total amount of motion imparted to the water at right angles to the -plane of the screw by one entire revolution even at the outer edge is -not quite equal to the slip, being only 1.67 foot. The rotatory motion -is still less, the total distance to which any particle of water is -displaced laterally, or at right angles to the axis of the ship, by one -entire revolution of the screw being at the outer edge only 0.69 foot, -and the maximum distance being in any screw only equal to half the slip, -and occurring at that part of the screw where the circumference is equal -to the advance of the ship due to one revolution. This maximum of -lateral motion is 0.9 foot, and takes place at 0.99 foot, or about 1 -foot from the centre. In this mode of considering the direction at which -the particles of water are acted upon by the plate of the screw I have -taken no notice of the effect of the friction upon the surface of the -screw, which, causing to be carried with it a film of water, will modify -more or less according to the degree of smoothness of the surface the -effect of the screw upon the water; and towards the centre this -friction, however smooth the surface may be made, will gradually become -equal to, and at last greater than, the propelling effect of that part -of the screw; but this defect applies only to a very small portion of -the whole area of the screw, and the absence of any very violent impulse -to the water in a direction approaching to a right angle with the axis -of the vessel, and which has always been assumed as an unavoidable evil -in the screw, will account for the absence I have observed upon of any -apparent rotatory motion. - -I would not pretend, however, to advance these circumstances which I -have observed, or these reasonings, as arguments whereon to found an -opinion of the action of the screw, the facts as proved by the -experiments are what I rely upon; but it is satisfactory to be able to -account for the results by circumstances actually observed, and the -reasons which suggest themselves. - -The effect of a propelling surface in the form of a screw, and moving at -a certain velocity, as compared with an equal surface moving at the same -velocity but applied in the shape of paddle-boards, having been -ascertained, it remains to determine the comparative power required to -give motion to that surface. - -The difficulty of determining this with any degree of accuracy from any -experiments which we could make on board the 'Archimedes' was very -great, but considering such results as I could obtain in conjunction -with experiments which I have since made in our own works, and with the -results upon steamboats recorded by others, and of those of experiments -made by Colonel Beaufoy on the resistance of bodies in water, I think we -may arrive at approximate conclusions sufficiently accurate for our -purpose, and which may safely be relied upon. - -In the case of the 'Archimedes' the engines were certainly not effective -well-working engines, the proportions of the gearing or wheel-work -between the engine and the screw was bad--such that the engine could not -attain its proper speed--the friction of the gearing (which, whether it -be a source of resistance necessarily attending the use of the screw or -not, I shall consider afterwards) was very great, and the surface of the -screw itself, which I had an opportunity of examining out of water, was -so rough as necessarily to create very much more friction than would be -caused by a tolerably smooth metallic surface. With all these sources of -resistance, and under these unfavourable circumstances, the power -calculated for the effective pressure on the piston and without -deduction for friction or other causes, which, for the sake of -distinction hereafter, I shall call the gross power, was about 145 -horses, the speed of the vessel being about 8-1/3 knots per hour, as -actually measured by the land, and full 9 knots as measured with great -care by heaving the common log, the midship section being, as before -stated, 122 feet, and the lines of the vessel not so good as those of -fast boats; comparing this with the gross power of the 'Great Western' -engines when propelling that vessel at the same velocity, with the -advantage of better lines and the other advantages arising from greater -dimensions, there does not appear any such discrepancy as to indicate -any loss of power by the use of the screw in the 'Archimedes'; on the -contrary, the power expended in the 'Great Western' is actually as great -as that in the 'Archimedes,' as compared with their relative midship -sections--and if any great allowance is to be made for the circumstances -which I have referred to of larger dimensions and better lines, there -would appear to be actually less power expended in proportion to the -dimensions and form of the 'Archimedes' than in the 'Great Western.' - -The results obtained with the 'Great Western,' which as regards speed -are similar to those of the 'Archimedes,' are necessarily taken from -experiments made when she was rather deep, and the speed thereby reduced -to 7.9 knots; but I have compared these with results reduced by -calculations from experiments at higher speeds, and I find them agree -satisfactorily--indeed, at the draft and consequent immersion of paddles -when in this state, I consider the 'Great Western' as very nearly at her -best as regards economy of power and effect produced. I should observe -that the particular experiments from which the following calculations -are deduced were made with the 'Great Western' in smooth water in the -Severn. I have added also some calculations deduced from data given by -Tredgold as to the performance of the 'Ruby,' a good boat with immense -surface of paddle-board. - -The comparison stands thus: - - +--------------------------------------+---------+-----------+-----+ - | | GREAT | | - | | WESTERN | ARCHIMEDES| RUBY| - +--------------------------------------+---------+-----------+-----+ - |ACTUAL DIMENSIONS: | | | | - | Midship section | 520 | 122 | 63 | - | Area of board immersed | 230 | --- | 64 | - | Area of a disc of diameter of screw | --- | 26 | -- | - | | | | | - |RELATIVE DIMENSIONS AND POWER: | | | | - | Area of propelling surface, midship | | | | - | section being = 1 | 0.442 | 0.213 |1.016| - | Gross power expended for one | | | | - | square foot of midship section | 1.023 | 1.026 |0.976| - +--------------------------------------+---------+-----------+-----+- - -The speed being the same, viz., 7.9 knots, the power expended is as -nearly as possible the same in the three, and equal to one horse-power -gross to one foot of midship section; while the relative propelling -surface in the 'Archimedes' is equal to only half that of the 'Great -Western,' and one-fifth that of the 'Ruby.' This _gross_ horse-power, it -will be observed, is _about_ equal to one-half a nominal horse-power. - -I have made several comparisons with recorded observations made on board -the 'Great Western' at different times, and with experiments made in -other vessels, and I find the same result; in estimating the powers used -more particularly in some comparisons with the 'Great Western,' I have -taken the mean pressure as ascertained on both sides of the piston, -while in the 'Archimedes' I only obtained that on the top of the piston, -which appears generally to be the best, and consequently the estimate is -made unfavourably to the 'Archimedes.' - -Such general results are all that I could obtain from the experiments on -board the 'Archimedes,' but since that time I have made some experiments -upon the friction of a plate of metal in water, and have compared these -results with the experiments of Colonel Beaufoy, and the conclusion I -have come to is that the power absorbed by friction in a well-made -screw, apart from all question of the means adopted for working it, -would not be such as to interfere with its beneficial application. - -The resistance created by the screw itself arises principally from two -sources--the resistance to the cutting edge and the tail-edge, and the -friction of the surface in contact with the water. The amount of the -first may of course be reduced to an unlimited extent by having a fine -edge, and practically such edge ought to be much finer than that of the -screw of the 'Archimedes.' - -The friction upon the surface will of course materially depend upon the -smoothness of that surface, and in the 'Archimedes' it was very rough, -the iron being corroded at many places, with exfoliations and small -holes--the corrosion arising apparently from the galvanic effect -produced by the iron and the ship's copper. - -The great number of revolutions required in the screw as compared with -those of the paddlewheel, leads a person to assume, without much -consideration, that a very high velocity is given to the cutting edges -and to the surface of the screw, and consequently that great friction -must be produced--this velocity is not, however, nearly so great as it -at first appears. - -In the present screw of the 'Archimedes' the velocity of the extreme -point, following its oblique or spiral course, is only about three times -that of the vessel, while the average velocity of either of these knife -edges or of the surface is not twice that of the vessel. - -Now without determining what the actual amount of these resistances may -be, we can at once satisfy ourselves that it cannot be very -considerable, by comparing it (which we have the means of doing) with -the resistance caused by the cutwater and any given portion of the -ship's bottom. The resistance of a knife-edge will be about as the -square of the velocity, and if we assume the surface friction to -increase in the ratio determined by Colonel Beaufoy--namely, at the -1.75th power, or as the 4th root of the 7th power of the velocity--then -the resistance of the knife-edge will be equal to the resistance of a -similar edge of about five and a-half times the length of the diameter -of the screw moving at the same rate as the vessel, and the surface -friction will be equal to that of a piece of the ship's bottom about six -and five-eighth times the area of the screw--or, in the case of the -'Archimedes,' the additional power absorbed by the friction of the screw -would be about equal to that absorbed by the friction of little more -than twice the space of the dead wood which had been cut out to receive -the screw--while the knife-edges would be about equivalent to three -knife-edges immersed in the water, of the same depth as the ship's stem. - -The actual amount of power absorbed in driving the 'Archimedes' screw -was probably about twenty horse-power gross, or from ten to twelve -nominal horse-power; but I have no doubt that a screw of similar -diameter and in good condition would not absorb half that power: and -this amount may be still further, and very much reduced, by increasing -the relative size of the screw to that of the ship, and thereby reducing -the slip, and proportionately reducing the number of revolutions -required. - -The great extent to which this is capable of being carried will at once -be seen when I state that if the ship's progress were made to be 7 feet -instead of 6 feet to each revolution of the screw, which a very slight -increase of diameter and pitch of screw would effect, the power absorbed -in driving the screw would be diminished in the ratio of the - - _____ _____ - 6^{2}^{4} \/6^{7} to 7^{2}^{4} \/7^{7}--that is, as 6-15/4 to 7-15/4, or about - as 3 to 2. - -I must repeat here the observation I have previously made, and remind -you that these calculations are not introduced as _proving_, but merely -as _explaining_, that which appears to me proved by the general results -of the experiments on the 'Archimedes'--namely, that the effect produced -was, considering all the circumstances, fully proportionate to the power -expended, while the experiments and calculations which I have since made -also satisfy me that these results may be very much improved upon. - -As regards the first of the two heads under which I stated that I -proposed to consider the subject, namely, the mere efficiency of the -screw as a propeller, I think but one conclusion can be drawn from the -results of the experiments quoted, and that is, that as compared with -the ordinary paddlewheel of sea-going steamers, the screw is, both as -regards the effect produced, and the proportionate power required to -obtain that effect, an efficient propeller. - -I limit the comparison to the ordinary paddlewheels of sea-going -steamers, first, because those are the circumstances which _we_ have -alone to consider; and, secondly, because it is _possible_, by -increasing the diameter and breadth of the paddles, which, for the -attainment of an adequate object is practicable to any extent in a mere -river boat, to render the action of the common paddle all but perfect, -and probably more effective than any other propeller. - -In considering the advantages and disadvantages likely to attend the use -of the screw propeller, I will, commencing with the latter, consider -such objections as have been advanced by others, as well as those which -may have occurred to myself. - -The only objections, however, which I think worth consideration are:-- - -First. The necessity of a peculiar form of vessel. - -Secondly. The situation of the screw under water, and consequently to a -certain extent unseen and inaccessible, and the liability to injury from -its position from grounding or in other ways. - -Thirdly. The probability of its being lifted out of water when the ship -pitched deep. - -Fourthly. The difficulty of getting up the required number of -revolutions, and the great defects of the mode employed in the -'Archimedes,' and the shaking caused by the machinery. - -As regards the form of vessel, undoubtedly a shallow boat, intended for -shallow waters, would be very unfit for the application of the screw, -which would probably require a greater depth of water than the whole -draft of the vessel; but I see no defect or difficulty of this -description in the vessel now under consideration, nor can I anticipate -any in any vessel this Company is likely to be interested in; a clean -run is the most essential condition, and I should suppose no ship was -ever built in which this principle of form was carried to a greater -extent than in our new iron ship. Her present form I believe to be -excellent for the screw, and with a very slight dropping of the keel -towards the stern, which can easily be done now without any expense, -assisted by the different trim, which, as I shall presently show, will -be effected by the use of the screw, the required draft of water will be -attained. - -It may, perhaps, be as well to mention here, that the diameter of the -screw, if in the same ratio to the midship section as in the -'Archimedes,' would be only 12 feet 3 inches, my friend Captain Claxton -having made a mistake upon this point in calculating it at 16 feet, and -that if increased only to 14 feet 4 inches, the diminution referred to -in a former part of my Report of one-third in the power lost in working -the screw would be effected; considering the speed we wish to attain, -probably 15 feet 6 inches would be a good diameter. Upon the whole I -think the vessel is as well fitted for a screw as she is for paddles, -and much better adapted for either than the 'Archimedes;' but if -originally intended for a screw, possibly some trifling modification in -the form and construction, principally of the keel near the stern, might -have been introduced which would have rendered the whole a more perfect -job than she would now be if altered--but the absence of this would in -no way lessen the efficiency of the screw, and I cannot think that any -alteration we might now be obliged to make would exceed in cost the sum -of 200_l_. - -Secondly, the inaccessibility of the screw and liability to damage; this -appears to me the objection most plausible, but I cannot say that I -attach much weight to it, particularly in the case of a vessel intended -for long voyages and across the ocean. During the whole passage in deep -water I consider the screw far less exposed to injury than a -paddlewheel, and that the chances of injury are so remote that even if -it were quite inaccessible it would still be altogether safer than -paddles, which are so much exposed; but it is by no means inaccessible, -the screw may be rendered stationary at any time or during any weather, -when it would be barely safe to stop the engines with common paddles, -and when it would be very difficult to do anything to the paddles even -if the engines were stopped, while the whole of the screw, bearings, -&c., may easily be examined and felt from above, and, if necessary, men -sent down with common diving jackets and hoods to replace bearings, or -attach tackle to move the screw, or clear away any obstacle entangled in -it. When in port I still think the chances of injury very remote; an -inspection of our model will satisfy you that from the form and size of -her midship section the vessel cannot lay in any position in which the -screw would touch the ground, while at that time the whole screw may be -very easily examined and replaced without any necessity for going into -dock. - -Thirdly, the probability of its being lifted out of water when the ship -pitches deep. - -This appears at first to be a very natural and an unavoidable objection, -but the result of observations proves that the motion of vessels, of -steamers at least, is not such as to cause the apprehended difficulty. -Among the observations made on board the 'Great Western' steam-ship by -Mr. Berkeley Claxton, under my direction, were measurements of the -angles of rolling and pitching, and from these it was evident that the -vessel never pitches to so great an angle as that to which she rises; -such a result might indeed have been anticipated by considering the form -of the vessel forward and aft, and the circumstance that a steamer is -almost invariably meeting or passing the seas, or, if overtaken by them, -is still going at a good rate, which reduces the relative speed of the -sea; consequently, although the vessel may be frequently thrown up very -violently forward, yet the stern, which has no displacement under water, -settles down quietly and heavily upon the surface; or, considering it in -another way, the variation of displacement at the stern is very rapid, -falling off almost to nothing at a few feet below the water-line, and -spreading out to a great extent at a few feet above, whilst forward the -difference of displacement is comparatively small, the centre of motion, -therefore, is thrown very far aft, and while the bows, which are also -opposed to the first shock, are thrown alternately high out of water or -plunged deeply into it, the stern floats nearly steady, the vessel -resting on its broad counter nearly as the centre of motion: whatever -may be the explanation such is the operation, not only as measured by -instruments, but more particularly as observed since, practically. - -In the 'Great Western' the whole cutwater and, it is said, a -considerable length of keel, is frequently seen out of water from the -bowsprit, while astern it is very doubtful whether more than half the -stern part was ever seen; marks have been made by my direction on the -rudder to observe this; as yet the 9-foot mark is the lowest seen, and -this occurring rarely, and for very short intervals. - -In the 'Archimedes,' during a voyage performed in her by Mr. Guppy from -Bristol to Liverpool, and during which they were exposed on more than -one occasion to violent pitching, the screw (which can be watched from -the deck) never was uncovered; and Mr. Smith and others on board the -'Archimedes,' whose whole conduct was such as to inspire unusual -confidence in all information obtained from them, assured me that such -was always the case. - -In the voyage to Oporto and back, in which I sent Mr. Berkeley Claxton, -he made the same observation; these facts, in conjunction with previous -and subsequent observations on board the 'Great Western,' convince me -that nothing is to be feared on this head; but even if the screw were -occasionally to be partly exposed, I know of no evil consequences likely -to ensue, as I shall clearly point out when referring to the -_advantages_ of this propeller over the common paddle. - -Fourthly, the difficulty of getting up the required number of -revolutions, and the great defects of the mode employed in the -'Archimedes.' - -Upon this point certainly the 'Archimedes' offers but a miserable -example, and the result is almost enough to prejudice the mind of any -person against the whole scheme; the proportions of the gearing, as I -have before stated, are so bad that the engines appear, even to the eye, -to labour ineffectually to get up their speed. The required speed of the -screw is not nearly attained, while the noise and tremor caused by the -machinery is such as to render the vessel uninhabitable, and perfectly -unfit for passengers, I should almost say for a crew. I never attached -much importance to these circumstances, because I felt convinced that -such a mere mechanical difficulty would by some means be overcome, if, -as I confess I did not then at all anticipate, the screw itself should -prove efficient. - -The most simple and effectual means of overcoming all objections on -these heads always appeared to me to be by the use of straps instead of -gearing; and all my experience, and I have seen a great deal of the -working of machinery by straps and ropes in the numerous works executed -by my father, led me to the conclusion that there existed no difficulty -whatever in sending the necessary power through a rope or hemp strap, -but I was hardly prepared to find the result so entirely satisfactory as -it has proved to be. - -In an experiment made in your works at the yard, I have sent through -two small whale lines, a power equal to about one-thirtieth of that -which would be required in the strap if used in the new ship, and this -without any slip or straining of the rope which would be injurious in -practice, and without any peculiar means of ensuring adhesion to the -drums; so that we have ascertained beyond doubt that sixty such whale -lines upon a drum of only 4 feet 3 inches diameter is adequate to our -wants, but if we suppose seventy lines of superior manufacture to that -used in the experiments with a perfect mode of tightening and working -upon a drum of 6 feet diameter, all of which can easily be had, it will -ensure the perfect and easy working of a mode of obtaining the required -number of revolutions of the screw without noise or tremor. The strap in -question would be only about 3 feet or 3 feet 3 inches broad, easily -replaced piecemeal, and even, if necessary, without stopping the -engines. - -All the difficulties enumerated under the fifth head may be considered -as entirely overcome, or rather as ceasing to exist; and so far from the -working of the screw involving difficulties and unavoidable friction, -noise, or tremor, it may be worked with unquestionable and perfect -facility, and as compared even with the best-made paddles in smooth -water, the whole machine will be noiseless. - -It is almost unnecessary that I should say that the screw, apart from -the gearing in use on board the 'Archimedes,' _cannot_ and _does not_ -produce the slightest tremor or noise--it was with some difficulty, and -at least only by attentively listening, that the revolutions of the -screw could be counted, even when disconnected and free from the noise -of the engine or gearing and the vessel being towed, and then only from -some defect in the bearings or the shaft of the screw causing a slight -beat. - -In thus answering the objections supposed to have been urged against the -use of the screw, I may probably have appeared to see everything in a -favourable light; unhesitatingly I admit that it is so, and that both -formerly when I was completely sceptical as to the mere efficiency of -the screw as a propeller, and since my doubts on that head have been -removed, I always felt that upon all other points the screw possessed -every superiority that could be desired over a common paddlewheel for a -sea-going vessel. - -I shall now proceed to point out the principal advantages peculiar to -the use of the screw; they are-- - -First. A considerable saving of weight, and that principally top weight. - -Secondly. The admitting of a better and simpler form of vessel, having -greater stiffness with the same quantity of material, and offering less -resistance to head wind and seas, and affording more available space -within. - -Thirdly. The operation of the screw being unaffected by the trim or the -rolling of the vessel, and allowing of the free use of sails, with the -capability of entirely disconnecting the screw or of varying the -multiplying motion so as to adapt the power of the engine to the -circumstance either of strong adverse winds or scudding. - -Fourthly. Perfect regularity of motion and freedom from the possibility -of violent shocks to the engines. - -Fifthly. The singularly increased power of steering given to the -vessel--and - -Sixthly. The great reduction in the breadth of beam. - -I have gone into some detail in calculating the weights of the parts -which are not common to the two systems, and I find that the difference, -or actual diminution in weight in favour of the screw as applied to our -new ship, is upwards of ninety-five tons; but that a much greater weight -even than this is transposed from the top of the ship to the bottom--no -less a mass than one hundred and sixty tons is removed from the level of -the paddle-shaft or from about 10 feet above the water-line, and -replaced by sixty-five tons at about 7 feet below the water-line; not -only is buoyancy, and consequently proportionate space for cargo, gained -to the extent of the difference, but the relief to the labouring of the -vessel in bad weather from the change of position must be immense. If -the reverse were under consideration, if in a vessel fitted for sea, -however stiff in trim or form, it were suggested to remove sixty-five -tons of her ballast, and to place one hundred and sixty tons upon her -deck, and thus navigate her across the Atlantic in all weathers, it -would probably be considered, not merely as highly dangerous, but as -actually impossible. Although such an opinion as that it would be -impracticable we now know would be incorrect, yet the extent of the -beneficial change is much more striking when considered in this way. As -regards the trim of the ship, about one hundred and forty-five tons -would be removed from nearly the centre of flotation, and the balance of -fifty tons added and distributed over the after part, principally quite -aft. - -I have not calculated the exact effect of this upon her trim; it would -only bring her down by the stern, and this is a defect which there -seems, as we too well know, never any difficulty in remedying. - -Secondly. The simplifying and improving the form of the ship--both as -regards strength and mass exposed to the wind and sea. - -The necessity of contracting the midships of a steamer, and making her -completely wall-sided, and forming a sort of recess to receive the -paddles, interferes considerably with the framing of the ship. In a -wooden ship of the size of our new one the whole beam of the ship would -have to be contracted in order to carry the planking through in a direct -line and obtain the requisite fore and aft tie as has been done in the -'Great Western'; in the new ship the almost infinite resources afforded -by the material used, enabled us to expand the sides and obtain breadth -of beam for cabin room, both before and abaft the paddles, and contract -the sides at the paddles as seen upon the plan; but in order to -strengthen this part, so evidently weak by form, much contrivance and -much material was required. By dispensing with paddles, the best form of -ship is left free to be adopted; perfect lines may be preserved, more -equal strength obtained with increased space, and the whole mass of -paddle-boxes and their accompanying sponsons and deck-houses swept away, -and the resistance of these huge wings to head winds or seas entirely -avoided. - -The space gained by avoiding the contraction is calculated by Mr. -Patterson to amount to two hundred tons measurement; this would be -entirely gained, and would not even involve increased dues or tolls, as -it would be added to the engine-room; it would therefore perhaps -counterbalance any loss of room caused by the shaft conveying the -movement from the engine to the screw, but I believe this nominal -increase at one part would not be so great, while in fact the ship would -really be more compact, and, though to a very small extent, a smaller -ship, as the sponsons would be removed. - -The third point of advantage named is perhaps the most important. With -paddles, the action is materially affected by the depth of immersion; -when the vessel is deep, and consequently the paddles deep, their action -is impeded, a greater part of the power of the engine is absorbed in -driving the paddle, the speed of the engine is reduced and the effect -diminished; when too light also the paddles do not take sufficient hold -of the water, the amount of slip increases and power is wasted; in -rolling the same effects are produced, and thus at those times when the -greatest effect is required, namely, with deep immersion or in bad -weather to overcome the increased resistance offered to the vessel, the -propelling power is least effective, and Captain Hoskins actually -estimates this loss as occasionally equal to two-thirds the whole power. - -The bad effects of one paddle being immersed too deeply, and the other -not sufficiently, also prevents the free use of the sails; and it must -often occur that the impediment thus offered to the working of the -paddles more than counterbalances the good effects of a tolerably fair -wind. With the screw the effect is constant, at least unaffected by the -position or motion of the ship, whether deep or light the screw acts -nearly the same, and as to rolling or heeling over, the screw would work -equally well (as long as it be immersed) if the vessel were on her -beam-ends or bottom upwards. - -The screw therefore leaves the ship free to be used as a sailing-vessel -to any extent that other circumstances will admit of, and as long as the -sails draw there can generally be no doubt that the wind is assisting -the ship. The screw may also be thrown in and out of gear at any time -and during any weather, either in case of accident to the engines, or in -the event of her scudding before a gale of wind, when the engine would -be useless; this last, however, I do not consider a probable occurrence, -particularly if another arrangement of which the screw is susceptible be -taken advantage of. - -If the motion be conveyed by a strap, as I have recommended, there is no -difficulty in having two or even three drums on the screw-shaft of -different diameters, and thus when the resistance to the ship is very -much increased by strong head winds, deep draught, and other causes, to -use the slow motion and obtain an increased propelling force, or when, -on the contrary, the vessel is running before the wind to use the quick -motion--by which, in both cases, a great increase of speed would be -attained. - -This is in fact obtaining at once and by simple means all those -advantages, and to a much fuller extent, which are aimed at in the -reefing-paddles. - -Fourthly, great regularity of motion is naturally consequent upon the -screw being unaffected by the rolling of the ship, and upon its being -immersed and not exposed therefore to blows from the sea, and except in -the case of its being lifted out of water, the resistance is perfectly -uniform and perfectly smooth. - -An engine could not have a work less capable of causing any jar or shock -as to the effect; even if lifted partially out of water the variation of -resistance would be as easy or soft, to use a mechanical term, as -possible, while the extent of the variation could never approach to that -to which paddles continually expose an engine. A heavy sea or a deep -plunge will occasionally bring the engines nearly to a stand; while at -other moments, if the engineers are to be believed, the paddles are left -free and the engines run away at a fearful speed. I am inclined to think -this description of the effects somewhat exaggerated; but certainly the -screw cannot by possibility be exposed to the same variations as the -paddles--it cannot be stopped by the action of the sea, indeed, being -wholly immersed, the resistance cannot be increased at all, while under -no circumstances can it be relieved to the extent to which paddles are, -which may both on some rare occasions be quite out of the water; and -therefore whether the resistance of the screw is so constant as I -believe it to be, or not, yet as compared with that offered by paddles, -it is certainly all but perfectly constant. - -Fifthly, the effect upon the steerage is singular, the mass of water put -into motion by the thrust of the screw is thrown directly upon the -rudder, and the consequence is not only that when the ship is going at -any given rate, the rudder is passing through the water at a greater -rate, and consequently is more sensible, and acts more powerfully upon -the ship; but even when the ship has no way, but the screw is at work, -the rudder is acted upon by water moving perhaps at two or three knots -per hour, and the vessel is still under command--this must be a most -important power to possess in a ship, and must materially diminish many -of the greatest dangers arising from a strong head wind and sea, and at -the same time and under the same circumstances must increase the speed -by improving the steerage. - -And lastly, her diminished breadth of beam. Important as this alteration -would be to any vessel, it is peculiarly so as connected with Bristol; -the total breadth, including paddle-boxes, would be at least 78 feet; -with the screw, and taking all the increased beam that might be -convenient, it would be under 50--very nearly 30 feet of difference. One -of the principal objections to her coming up the river would be removed, -and the dock gates might easily be made to receive her.[201] - -There are many other points upon which comparisons may be drawn, but I -am not aware that any very important differences exist. - -As regards first cost I believe there would be little difference--if -any, it would be in favour of the screw; as a reduction of ninety-five -tons of iron can hardly fail to cause some saving, although some portion -of the substituted machinery may be more costly per ton. - -As regards wear and tear I can have no doubt that some considerable -saving would be effected; the paddles are a constant source of trouble -and expense, and seem never to be capable of being kept in good repair; -indeed, they are huge and comparatively light frameworks subjected to -extraordinary and constantly repeated shocks, each arm receiving direct -about 260,000 very sharp blows per voyage, independently of the more -violent shocks from heavy seas, while the screw can be subjected to no -such constant source of mischief. - -From all that I have said it must be evident to you, gentlemen, that my -opinion is strong and decided in favour of the advantage of employing -the screw in the new ship; it certainly is so. I am fully aware of the -responsibility I take upon myself by giving this advice, I am also fully -sensible of the large amount we have at stake, and I have not forgotten -the nature and tone of the observations which have on more occasions -than one been so freely made by individuals upon the course we have -hitherto pursued; although, and I have pleasure in referring to the -fact, this course has in every instance where results have been obtained -proved successful; but my conviction of the wisdom, I may almost say the -necessity, of our adopting the improvement I now recommend is too -strong, and I feel it is too well founded, for me to hesitate or to -shrink from the responsibility. - -I think I have hardly advanced an opinion which I have not supported, -and in most cases preceded, by a statement of facts, leaving no doubt as -to the correctness and safety of relying on these opinions; still it -would be too much to hope that my mode of laying before you these facts -which I have collected and the opinions I have formed could produce as -strong a conviction in your minds as the consideration of them has in my -own; but if you bear in mind that the actual results of the fair and -full trial of the 'Archimedes' for several months has completely -established the fact of the efficiency of the screw as a propeller; that -the experiments I have made, as well as the general and apparent results -of her working, have equally satisfactorily explained the fact of the -power required being no greater in proportion to the effect produced -than in the 'Great Western' steam-ship, and many other good steamboats; -and that these results are satisfactorily explained by theory, you -cannot fail to draw the same conclusion that I have done as to the -general question of at least the equal efficiency of the screw. - -As to the comparisons I have drawn between the general and what I may -call the indirect advantages of the one mode of propelling over the -other, they seem to me so evident that I am disposed to apologise to you -for having occupied your time in pointing them out, and we have the -satisfaction of knowing that they are now very generally admitted, -particularly by practical men. - -In conclusion, I must observe that much more detailed information and -recorded results than appear on the face of this Report have been -required to enable me to form correct comparisons, and to reduce to -calculation and to actual figures and amounts many results observed; and -that it would have been impossible for me to have given you such clear -and positive facts on many most important points without the very -detailed observations made and recorded by Mr. Berkeley Claxton in the -several voyages of the 'Great Western,' and also in one on board the -'Archimedes.' - -The information obtained from these logs has been, and may still be, of -the greatest importance to us in our future working, and I have much -pleasure in adding that the manner in which my directions were carried -out was highly creditable to Mr. Berkeley Claxton, who, I think, has -conferred a great benefit on the Company by his labours. I have to -express also my thanks to my friends Captain Claxton and Mr. Guppy for -their assistance in the various experiments which have been made, and in -working out the results. - - I am, Gentlemen, - - Yours very faithfully, - - (Signed) I. K. BRUNEL. - - - - -INDEX - - -'Adelaide' steam-ship, built under Mr. Brunel's directions, 290 - -Admiralty, Mr. Brunel's connection with the, respecting the screw propeller, 283. - Communication with the, on floating gun-carriage, 459 - -Airy, G. B., Astronomer Royal, member of the Gauge Commission, 117. - Correspondence with Mr. Brunel on astronomical observations for the 'Great Eastern,' 321 - -Angarrack, viaduct at, 189 - -'Archimedes' steamer, the screw propeller used in the, 253. - Experiments made in the, 254 - -Armstrong, Sir W. G. - His hydraulic machinery at Paddington station, 85 _note_.^{1} - Engaged with Mr. Brunel on gunnery investigations, 452. - Letter to, 454, 461 - -Atlantic cable expeditions of the 'Great Eastern,' 412. - Loss of the first cable, 412. - A second one laid, and the first recovered, 413. - The French cable of 1869, 413 - -Atmospheric system of propulsion on railways, 131. - Description of this method of traction, 134. - History of its introduction prior to 1844, 136. - Mr. Brunel's views respecting it, 137. - His report recommending its adoption on the South Devon Railway, 138. - Grounds of his recommendation, 142. - Select Committee on, 144. - Working of the system, 153. - Imperfections of engines, 154, and longitudinal valve, 157. - Mr. Brunel's report on the failure of the Atmospheric apparatus, 159. - Abandonment of the system, 164 - -Australian Mail Company, Mr. Brunel appointed engineer of the, 290 - - -Barlow, Professor P., member of the Gauge Commission, 117 - -Barlow, W. H., 57 - -Bath, station at, 84 - -Bath, bridges at, 175, 179 - -Bathford, bridge at, 175 - -Beamish, Richard, his account of Sir Isambard Brunel's block machinery at Portsmouth, quoted, 3. - Joins the Thames Tunnel works, 21 - -Bennett, Joseph, Mr. Brunel's secretary, 92 - -Berks and Hants Railway, 88 - -Birmingham and Oxford Junction Railway, 90 - -Birmingham, Great Western extension to, 124 - -Birth of Mr. Brunel, 1 - -Blake, H. W., consulted by Mr. Brunel on the 'Great Eastern,' 297 - -Block machinery at Portsmouth, Sir Isambard Brunel's, 2 - -Bourbon, Ile de, Sir Isambard Brunel's suspension bridges for the, 5. - Description of them, 40 - -Bourne viaduct, 181 - -Box Tunnel, 70 _note_^{1}, 72, 81. - Criticism as to its safety, 81. - Letter from Mr. Brunel on the, 81 - -Bremner, A., 263, 280 - -Brentford, dock at, 440 - -Brentford, extension of the Great Western Railway to, 86 - -Brereton, Robert Pearson, chief of Mr. Brunel's engineering staff, 92, 210, 215 _note_^{1}, 217 _note_^{1}, 223, 225, 437, 438 _note_^{1} - -Brickwork, use of, 59. - Bridges in, 172 - -Bridges, suspension, Sir Isambard Brunel's: in the Ile de Bourbon, 5, 40; designs for the Serpentine, and for the Thames at Kingston, 5. - Mr. Brunel's: at Clifton, 46; Charing Cross, 59 - -Bridges, railway, 171. - 1. Brickwork and masonry bridges, 172. - Flying bridges, 176. - Skew bridges, 177. - Letter from Mr. Brunel on bridge construction, 178. - 2. Timber bridges and viaducts, 179. - 3. Cast-iron bridges, 190. - 4. Wrought-iron bridges, 192. - Girder bridges, 193. - Opening bridges, 195. - Trussed bridges, 199. - Extracts from letters on bridges of large span, 212 _note_^{1}. - Experiments on matters connected with bridge construction, 227 - -Bristol, Mr. Brunel's early connection with, 58, 64. - Station at, 84. - Bridges at, 175, 195. - Floating Harbour, 422. - Proposed improvement of the port, 426. - New lock at, 427 - -Bristol and Exeter Railway, 86 - -Bristol and Gloucester Railway, 90 - -Bristol and South Wales Union Railway, 90 - -Briton Ferry Docks, 437 - -Broad Gauge. _See_ Gauge - -Brunel, Sir Marc Isambard, birth of, 2. - Arrives in England, 2. - Marries Miss Sophia Kingdom, 2. - Designs the Block machinery at Portsmouth, 2. - Veneering machinery, 5. - Shoe machinery, 5. - Designs suspension bridges for the Ile de Bourbon, 5, 40. - Experiments on carbonic acid gas, 5, 42. - Proposes the Thames Tunnel, 5. - Extracts from his Journal relating to the Rotherhithe shaft, 10. - Extracts from his Journal relating to the works at the Thames Tunnel up to January 1828, 16. - His death, 39. - Hoop iron introduced by, in brickwork, 177. - Designed a large timber bridge to cross the Neva, 211 _note_^{2} - -Bullo Pill opening bridge, 197 - - -Caermarthen, opening bridge at, 198 - -Carbonic acid gas, experiments on, by Sir Isambard Brunel and Mr. Brunel, 5, 42 - -Cast-iron bridges, 190. - Mr. Brunel's views as to the use of cast iron in bridge construction, 190, 192 - -Cheltenham and Great Western Union Railway, 88 - -Chepstow bridge, 203. - Mode of forming piers, 203. - Description of superstructure, 206. - Floating and erection, 209 - -Clarke, Seymour, 117 - -Claxton, Captain, 57. - Assists Mr. Brunel at the floating of the Chepstow bridge, 210. - And the Saltash bridge, 222. - Appointed Managing Director of the Great Western Steam-Ship Company, 234, 242, 247. - Letter to, from Mr. Brunel, on the 'Great Britain,' 264. - Goes to Dundrum to carry out Mr. Brunel's plans for the protection of the 'Great Britain,' 272. - Letter to, from Mr. Brunel, on the breakwater, 272. - Report of, on breakwater, 274. - Superintends floating of the 'Great Britain,' 280. - Consulted by Mr. Brunel on the 'Great Eastern,' 291, 297. - Floating Harbour, Bristol, 424 - -Clifton Suspension Bridge, origin of the, 47. - Mr. Brunel's designs, 47. - Rejected by Mr. Telford, 51. - Mr. Telford's own design, 52. - Second competition, 52. - Mr. Brunel successful, and appointed engineer, 53. - The site described, 54. - Description of the design, 55. - Architectural features, 56. - Commencement of the work, 56. - Completed, 57 - -Coles, Captain Cowper, 461 - -Construction of works, letter on, 178 - -Continuous girders, 208 - -Cork and Youghal Railway, 91 - -Cornwall Railway, 87. - Viaducts on, 185 - -Crystal Palace at Sydenham, water-towers of the, 448 - -Cylinders, of Chepstow bridge, method of sinking the, 204. - The great cylinder of the Royal Albert Bridge, 214 - - -Dalkey Railway, Atmospheric System on, 131 - -Dartmouth and Torbay Railway, 87 - -Death of Mr. Brunel, 520 - -Dock and pier works: - Monkwearmouth, 418; - Bristol, 422; - Plymouth, 433; - Briton Ferry, 437; - Brentford, 440; - Neyland, 443 - -Draught, Mr. Brunel's paper on, 101 _note_^{1} - -Dublin, railway to Wicklow from, 91 - -Dundrum Bay, stranding of the 'Great Britain' in, 263 - - -Early life of Mr. Brunel. - He goes to school at Chelsea, 4; at Brighton, 4; at Paris, 5. - Employed in his father's office, 5. - Engaged at the Thames Tunnel, 6. - References by Sir I. Brunel to his exertions, 17, 19, 21, 22, 25, 33. - Appointed resident engineer, 25 _note_^{1}. - First irruption of the river, 29. - Second irruption, 35. - Accident, 36. - Visit to Plymouth, 46 - -Eastern Bengal Railway, 91, 195, 517 - -Eastern Counties Railway, gauge adopted on the, 105 - -Eastern Steam Navigation Company, formation of the, 291. - _See_ 'Great Eastern' - -Egypt, visit to, 517 - -Electric telegraph, application of the, in connection with railways, 155 - -Engineer, Mr. Brunel's view of the position of, 475. - Of joint-engineer, 476. - Of consulting engineer, 477. - Of the position of the engineer in relation to the contractors, 477. - To the Directors, 478. - Remarks on interference of Directors with assistant engineers, 481. - On State control over engineering works, 486 - -Experiments: - Strength of timber, 182, 227. - Cast-iron girders, 190, 191. - Wrought-iron girder, 193. - Riveting, 194, 228. - Continuous beams, 209, 229. - Bridge construction, 227. - Ropes and chains, 228. - Friction, 348, 368, 385 - - -Faraday, M., his experiments on the liquefaction of gases, 42. - Consulted by Mr. Brunel on the Kyanising process, 189 - -Field, Cyrus, 411, 414 - -Field, J., consulted by Mr. Brunel on the 'Great Eastern,' 297 - -Floating gun-carriage, 454 - -Floating harbour at Bristol, 422 - -Floating pier, proposed at Portishead, 426. - In Mill Bay, 436 - -Florence and Pistoja Railway, 91 - -Flying bridges, 176 - -Ford, Captain Robert, consulted by Mr. Brunel on the 'Great Eastern,' 297 - -Friction, experiments and observations on, 348, 368, 385 - -Froude, W., letter to, describing floating of the 'Great Eastern,' 389 - - -Gathampton, bridge at, 174 - -Genoa, Novi, and Alessandria Railway, 91 - -Gauge of railways, difference between the broad and narrow, 99. - Origin of the ordinary gauge, 99. - Adoption of the broad gauge on the Great Western Railway, 101, 106. - Reasons for its adoption, 102. - Attacks on, 106. - Reports of Mr. Wood and Mr. Hawkshaw on, 107. - Report by Mr. Brunel on, 107. - Northern extension, 116. - Inconveniences of a break of gauge, 116. - Royal Commission on the gauge question, 117. - Report of the Commissioners, 117. - 'Observations on the Report,' 119. - Report of the Board of Trade, 122. - Act for regulating gauge, 122. - The mixed gauge, 124. - Summary of the advantages of the broad gauge, 127. - Partial abandonment of the broad gauge, 127, 129. - Report on the broad gauge, 525 - -Gilbert, Davies, appointed referee in the second competition for the Clifton Suspension Bridge, 52. - Recommends Mr. Brunel's design, 53 - -Girder bridges, 193 - -Glennie, W., 215 _note_^{1} - -Gloucester, opening bridges near, 196 - -Gloucester and Dean Forest Railway, 88 - -Gooch, Sir Daniel, 117, 119. - Experiments by, 125 - -Gravatt, William, an assistant engineer at the Thames Tunnel, 26 - -'Great Britain' steam-ship, commencement of the, 247. - Report on the engines, 249. - Adoption of the screw propeller, 254. - Principal features of her design, 255. - Arrives in the Thames, 261. - Her voyages, 262. - Stranded in Dundrum Bay, 263. - Letter from Mr. Brunel on the subject, 264. - His reports to the Directors, 267, 273. - Construction of breakwater, 274. - Floating of the ship, 280. - Her subsequent history, 282. - Dimensions of ship and engines, 282 - -'Great Eastern' steam-ship, origin of the project, 291. - Memorandum by Mr. Brunel to the Directors of the Eastern Steam Navigation Company, 292. - He is appointed engineer, 293. - Letter on the form and dimensions of the ship, 294. - Report on mode of proceeding, 296. - On enquiries relating to the draught and form of the vessel, 297. - On the dimensions, 299. - Tenders invited, 300. - Report on tenders, 301. - Commencement of the work, 304. - Extracts from Mr. Brunel's memoranda, 304, 310. - Letters on his position as engineer, 311. - Report describing the ship, 315. - Letter to the Astronomer Royal, 321. - The observers' department in the ship, 322. - Captain Harrison appointed to the command, 323. - Memorandum on the management of the ship, 324. - Letter on the duties of chief engineer, 335. - Suspension and resumption of the works, 339. - Reasons for launching the ship broadside to the river, 340. - Adoption of iron sliding-surfaces, 343. - The ways and cradles, 345. - Motive power, 348. - Checking gear, 351. - River tackle, 352. - Letter to Captain Harrison on the river tackle, 354. - Letter to the Directors respecting the operation of launching, 355. - Memorandum of arrangements and intended mode of proceeding, 356. - Particular instructions, 358. - Final preparations, 359. - Commencement of the launch, 360. - Accident at one of the drums, 361. - Failure of the first attempt, 362. - Second attempt, 364. - Report on operations, 366. - Progress of the launch, 368. - Suspension of operations, 376. - Report and memorandum, 377. - Re-commencement, 379. - Floating of the ship, 382. - Experiments and observations on friction, 385. - Letter to Mr. W. Froude, describing the floating, 389. - Formation of the Great Ship Company, 393. - Progress of the works to Mr. Brunel's last illness, 393. - Completion of the ship, 393. - Voyage to Weymouth, 393. - Explosion of water-heater, 393. - Storm at Holyhead, 395. - Description of the ship, 396. - Her first voyages to New York, 403. - To Quebec, with troops, 404. - Accident to rudder, and loss of paddlewheels, 405. - Voyages in 1862, 407. - Accident off Montauk Point, 407. - Formation of Great Eastern Steam-Ship Company, 409. - Remarks on performance of ship, 409. - Employed in laying Atlantic cables, 412. - The Indian cable, 414. - Dimensions of ship and engines, 416 - -Great Exhibition of 1851, Mr. Brunel's opinion respecting prizes to exhibitors, 445. - His part in the work of the Building Committee, 446. - Supports Sir Joseph Paxton's design, 447 - -Great Western Hotel, 86 - -Great Western Railway, origin of the, 63. - Mr. Brunel appointed engineer, 64. - Survey of the country, 65. - Bill for a line from London to Reading, and Bath to Bristol, read a second time, and referred to a committee, 66. - Opposition to the Bill, 67. - Plan of entering London, 68. - Mr. Brunel's cross-examination, 69. - The Bill passed by the Commons, but thrown out in the Lords, 70. - A Bill for the whole line introduced, read a second time, and committed, 71. - Evidence taken before the Commons' Committee, 72. - Evidence before the Lords' Committee, 73. - The Bill receives the Royal Assent, 74. - Construction of the line, 80. - Opening from London to Bristol, 80. - Levels and inclines, 80, 104. - The Box Tunnel, 81. - The Bath and Bristol stations, 84. - Paddington station, 84. - Branches and extensions of the railway, 86, 88, 90. - Adoption of the broad gauge, 106. - The permanent way, 108, 111. - Meeting of shareholders on broad gauge, 111. - Extension of the Great Western system, 116 - -'Great Western' steam-ship, formation of the company, 233. - Details of the construction of the vessel, 234 _note_^{2}. - Report on the selection of the builders of the engines, 235. - Controversy with Dr. Lardner, 237. - Launch of the vessel, and voyage to London, 241. - Return to Bristol, 242. - Fire on board, and accident to Mr. Brunel, 242. - First voyage to New York, 243. - Subsequent history, 244. - Dimensions of ship and engines, 245 - -Gunnery experiments, 452 - -Guppy, T. R., 148, 233, 234, 247, 253, 254. - Letter to, on iron-ship building, 259 - - -Hammond, J. W., 65, 92 - -Hanwell, bridge at, destroyed by fire, 190 - -Hanwell viaduct, 172 - -Harrison, Captain, 223. - Appointed commander of the 'Great Eastern,' 323. - Letter to, on the river tackle, 354. - At the launch, 362, 370, 382, 392 - -Haverfordwest, opening bridge at, 198 - -Hawkshaw, J., 57. - Report on broad gauge and permanent way, 107 - -Henley branch of the Great Western Railway, 86 - -Hungerford Suspension Bridge, 57, 59 - - -India, railway works in, 91 - -Indian Cable expedition of the 'Great Eastern,' 414 - -Institution of Civil Engineers, 516 _note_^{2}, 521 - -Inventors, communications with, 485 - -Ireland, railway works in, 90 - -Italy, Mr. Brunel's railway works in, 91, 510 - -Ivybridge viaduct, 182 - - -Kennet, bridge over the river, 175 - -Kidwelly, opening bridge at, 198 - -Kyanising process, 189, 421 - - -Landore, viaduct at, 183 - -Lane, Michael, 29 - -Lardner, Dr., 114 _note_^{1}. - Opinions respecting ocean steam navigation, 237 - -Llansamlet, flying arches near, 176 - -Llynvi Valley Railway, 89 - -Locke, Joseph, 62, 74. - His address on the death of Mr. Brunel, 521 - -Locomotive power, comparison of, with stationary power, 142, 166 - -Loughor, opening bridge at, 197 - - -Maidenhead bridge, 96, 173 - -Masonry, bridges in, 172 - -Maudslay and Field, 15, 148, 236, 284 - -Milford Haven, 88, 443 - -Monkwearmouth, docks at, 417, 418 - -Moulsford, bridge at, 174 - - -Nasmyth, James, his steam hammer designed, 252 _note_^{1}. - Letter to, on gunnery experiments, 452 - -Neath, improvement of river, 438 _note_^{1} - -Newport viaduct, 185, 199 - -Neyland, pier at, 443 - - -Ocean steam navigation, Mr. Brunel's connection with, 231, 313 - -Opening bridges, 195 - -Oxford, Mr. Brunel created a Doctor in Civil Law at, 516 - -Oxford and Rugby extension of the Great Western Railway, 90, 116 - -Oxford branch of the Great Western Railway, 86 - -Oxford, Worcester, and Wolverhampton Railway, 90, 116 - - -Paddington station, 84 - -Paris Exhibition of 1855, letter on decorations conferred at, 489 - -Parkes, Dr., medical superintendent of Renkioi Hospital, 468. - Report of, on hospital buildings, 468 - -Patent laws, Mr. Brunel's opinions on the, 212 _note_,^{1} 450, 451, 454, 485, 489, 497 - -Patterson, W., 234, 247, 263 - -Paxton, Sir Joseph, his design for the Great Exhibition building, 447 - -Permanent way on the Great Western Railway, 108, 535 - -Plymouth Great Western Docks, 433 - -Polygonal rifle, 449 - -Portishead, proposed pier at, 426 - -Prince Consort, H.R.H. the, opens the Royal Albert Bridge, 226. - Present at floating of the 'Great Britain,' 259 - -Private life of Mr. Brunel, 499. - Early reminiscences, 500. - Removal to Duke Street, and marriage, 505. - His taste in art, 506. - First journey to Italy, 508. - Half-sovereign accident, 511. - Purchase of property in Devonshire, 514. - Life at Watcombe, 515. - Failing health, 516. - Journeys to Switzerland and Egypt, 516. - Letter from Philae, 517. - His last illness, 520 - - -Quaker's Yard, viaduct at, 89 - - -Railways, sketch of, in England prior to 1833, 61. - Extent of Mr. Brunel's, 79. - Great Western, 80. - Branches to Oxford, 86. - Windsor, 86. - Wycombe, 86. - Uxbridge, 86. - Henley, 86. - Brentford, 86. - Bristol and Exeter Railway, 86. - South Devon, 87. - South Devon and Tavistock, 87. - Cornwall, 87. - Branch lines now incorporated with Great Western Railway: - Berks and Hants, 88. - Wilts and Somerset, 88. - Cheltenham and Great Western Union, 88. - Gloucester and Dean Forest, 88. - The South Wales, 88. - The Taff Vale, 89. - The Vale of Neath, 89. - The Llynvi Valley, 89. - The South Wales Mineral, 89. - Bristol and South Wales Union, 90. - Bristol and Gloucester, 90. - The Oxford and Rugby, 90. - Birmingham and Oxford Junction, 90. - Oxford, Worcester, and Wolverhampton, 90. - Ireland, 90. - Italy, 91. - India (Eastern Bengal), 91 - -Railway Structures, letter on the Royal Commission on the Application of Iron to, 192, 486 - -'Rattler' steam-ship, trials with the, 287 - -Rendel, J. M., 211, 433 - -Renkioi, hospital buildings at, 461. - Description of the buildings, 463. - Dr. Parkes's report on the formation and general management of the hospital, 468 - -Rennie, G. and J., 148 - -Richards, Westley, letters to, on polygonal rifle, 450 - -Riveting, experiments on, 194, 228 - -Ropes and chains, experiments on, 228 - -Rotherhithe shaft of the Thames Tunnel, construction of the, 9 - -Royal Albert Bridge at Saltash, 211. - Plans for crossing the river Tamar at Saltash, 211. - Trial cylinder for centre pier, 213. - Report on making bridge for a single line, 214. - Mode of construction of centre pier, 214. - Description of superstructure, 218. - Floating of first truss, 221. - Lifting of first truss, 224. - Floating and lifting of second truss, 225. - Opening by H.R.H. the Prince Consort, 226 - -Royal Society, 516 _note_^{1} - -Russell, J. Scott, builds the 'Victoria' and 'Adelaide,' 290. - Assists Mr. Brunel in maturing designs of the 'Great Eastern,' 291, 292, 297. - Letter to, on the form and dimensions of the ship, 294. - Tender accepted for hull and paddle-engines, 301 - - -St. Mary's viaduct, 181 - -St. Pinnock viaduct, 186 - -Saltash bridge. _See_ Royal Albert Bridge - -Samuda, J., 131, 134, 148, 160 - -Saunders, C. A., 92, 117, 119 - -Screw propeller, the, adopted for the 'Great Britain,' 254. - Communications on, with the Board of Admiralty, 283. - Trials with the 'Polyphemus,' 284. - With the 'Rattler,' 287. - Report recommending adoption of, 539 - -Shield, Thames Tunnel, the, 11, 12 - -'Sirius' steam-ship, 241 - -Skew bridges, 177 - -Smith, F. P., the screw propeller, 253, 287. - Consulted by Mr. Brunel on the 'Great Eastern,' 297, 298 - -Smith, Sir F., member of the Gauge Commission, 117 - -Smyth, C. Piazzi, Astronomer Royal for Scotland, correspondence with Mr. Brunel on astronomical instruments for the 'Great Eastern,' 322 - -Sonning Cutting brickwork bridge, 175. - Timber bridge, 179 - -South Devon and Tavistock Railway, 87. - Viaducts, 188 - -South Devon Railway, 87. - Course of the line, 132. - Atmospheric System adopted on the, 138. - Viaducts, 182 - -South Wales Mineral Railway, 89 - -South Wales Railway, 88. - Viaducts, 183, 194 - -Standard drawings, 172 _note_^{2} - -Stationary and locomotive power, comparison of, 142, 166 - -Statue of Mr. Brunel, 520 _note_^{1} - -Stephenson, George, 61, 62, 70, 74, 99 - -Stephenson, Robert, 62, 106, 107, 134 - Atmospheric System, 136, 137 _note_^{1}, 138, 144. - Conway and Britannia bridges, 221, 223. - Launch of the 'Great Eastern,' 375, 376, 377, 378, 384 _note_^{1}, 485, 516, 517, 521 - -Stonehouse viaduct, 181 - - -Taff Vale Railway, 89, 104 _note_^{1} - -Tamar, plans for crossing the river, 5 _note_^{2}, 46, 211 - -Telford, T., appointed referee to decide upon the plans for the Clifton Suspension Bridge, 51. - Rejects Mr. Brunel's plan, 51. - Designs one himself, 52. - His plan described, 52 - -Thames Tunnel, project of, first occupies Sir Isambard Brunel's attention, 5. - Plans suggested for the construction of a tunnel, 6. - Borings, 7. - Remarks on borings, 8 _note_^{1}. - Commencement of the work, 9. - Construction of the Rotherhithe shaft, 9. - Description of the shield, 12. - Journals of Sir I. Brunel of the progress of the work, 10, 11, 16. - Mr. Brunel appointed resident engineer of, 25 _note_^{1}. - First irruption of the river, 29. - Second irruption, 35. - Works suspended, 37. - Resumed, 38. - The Wapping shaft, 38. - Completed and opened, 39. - Its subsequent history, 39 _note_^{1} - -Thompson, Dr. Seth. - Letter on the half-sovereign accident, 511 - -Timber bridges and viaducts, 179 - -Timber, experiments on strength of, 182, 227 - -Torquay branch of the South Devon Railway, 87 - -Trussed bridges, 199 - - -Uxbridge branch of the Great Western Railway, 86 - - -Vale of Neath Railway, 89. - -Viaducts, 171 - -Vick, Alderman William, his bequest for a bridge at Clifton, 47 - -'Victoria' steam-ship, built under Mr. Brunel's direction, 290 - -Vignoles, C., 74 - - -Walker, J., 107 - -Walkham viaduct, 189 - -Wapping shaft of the Thames Tunnel, construction of the, 38 - -Watcombe, Mr. Brunel's life at, 514 - -Watt, James & Co., 148. - Tender accepted for screw engines of the 'Great Eastern,' 301 - -West Cornwall Railway, 87. - Viaducts, 189 - -Westminster Abbey, memorial window in, 520 _note_^{1} - -Wilts and Somerset Railway, 88 - -Windsor branch of the Great Western Railway, 86 - -Windsor bridge, 200. - Description of superstructure, 200. - Mode of forming piers, 201 - -Wire gun, 453 - -Witness, Mr. Brunel's reputation as a, 69, 93, 505 - -Wood, Nicholas, 101. - Report on broad gauge and permanent way, 107 - -Wrought-iron bridges, 192 - -Wrought-iron girder, experiments on, 193 - -Wyatt, Sir M. D., 84 - -Wycombe extension of the Great Western Railway, 86 - - -LONDON: PRINTED BY - -SPOTTISWOODE AND CO., NEW-STREET SQUARE - -AND PARLIAMENT STREET - - * * * * * - - -Typographical errors corrected by the etext transcriber: - -known method of makng=> known method of making {pg 45} - -consits merely of=> consists merely of {pg 109} - -every calcluation=> every calculation {pg 527} - - - * * * * * - - -FOOTNOTES: - -[1] To avoid confusion, Sir Isambard Brunel has been called throughout -by that designation, the one by which he is generally known: he was -knighted on March 24, 1841. - -His Life has been written by Mr. Richard Beamish, F.R.S. (London, 1862.) - -[2] Lady Brunel survived her husband five years. Of their children, -three lived to maturity, one son, Isambard Kingdom, and two daughters, -Sophia, wife of the late Sir Benjamin Hawes, K.C.B., Under Secretary of -State for War, and Emma, wife of the Rev. George Harrison, Rector of -Sutcombe. - -[3] He was sent to Paris to recover his knowledge of French, which had -got rather rusty at school, and also to study mathematics. He retained -through life a great admiration of the method of teaching this subject -which was adopted in France. - -In addition to the time spent in the study of mathematics and languages, -Mr. Brunel occupied himself on his holidays in examining the various -engineering works going on in Paris, and he used to send his father -drawings and descriptions of them. - -[4] Sir Isambard was also consulted upon a proposed suspension bridge -over the Tamar at Saltash, where Mr. Brunel subsequently built the Royal -Albert Bridge. - -[5] This history has been written by Mr. Beamish in his _Life of Sir -Isambard Brunel_, pp. 202-304, and also, up to the year 1828, in the -very valuable work by Mr. Henry Law, C.E., entitled 'A Memoir of the -several Operations, and the Construction, of the Thames Tunnel,' and -published by the late Mr. Weale in his _Quarterly Papers on -Engineering_. - -[6] For an account of these earlier attempts see Law, pp. 3-7. - -[7] This expectation does not seem to have been realised, as there was -never any considerable traffic through the Thames Tunnel. Perhaps, -however, it would have been otherwise had the large descents for -carriages and horses been constructed. - -[8] The results obtained by these borings were no doubt fallacious, but -not to the extent which has sometimes been imagined. At a meeting of the -Institution of Civil Engineers, in November 1849, Dean Buckland called -attention to 'the evils arising from the ignorance of the engineers who -reported to Sir Isambard Brunel, previous to the commencement of the -Thames Tunnel, that the whole of the bottom of the river at that spot -was London clay.' Whereupon Mr. Brunel rose and said, that he 'agreed -that knowledge of every kind was most desirable, and that it would be -well if engineers were generally much better informed on many subjects -which would be useful, and more particularly on matters connected with -geology; at the same time he could not admit that they were deficient in -that knowledge of the surface of the earth which was necessary for the -purpose of guiding them in their work. It might be true that many -members of the profession were, like himself, not perfectly well -acquainted with the minute geological characteristics of the soils they -had to deal with, but he thought the education and the practical -experience of the profession generally rendered them well acquainted -with those features and characteristics which were necessary for their -guidance in the design or execution of work. He must also say a few -words in defence of those persons (now nearly all dead) who made the -borings in the Thames, and were stated to have made so fallacious a -report previous to the commencement of the Tunnel. Now, although that -statement had by constant repetition become a sort of historical fact, -it was really only one of those popular fallacies which obtained too -ready credence in the world. The position of the Tunnel was not -determined by any report, or by the result of any borings, but with a -view to establishing a communication between particular localities for -encouraging the traffic which was anticipated from the facility of -access to the docks, and for other local reasons, such as the general -direction of the roads and streets on both shores. After the position -was settled, and not until then, borings were made to ascertain what -soils might be expected in that part of the river. It must be remembered -that these borings were made full twenty-five years ago, when boring in -the bed of a river through a depth of water of nearly thirty feet was -not an ordinary occurrence. The tool then generally employed was the -worm, and tubes were not even used in such cases. The borings showed the -existence in that spot of something which, in the ordinary acceptation -of the term, might have been inadvertently called London clay, but he -had no recollection of its geological designation having ever been -thought of. It was reported and shown to be a very fair clay for working -in.... The errors which were made in giving the results of the borings -did not, in fact, arise from ignorance, but from mechanical defects in -the tools, for it was subsequently discovered that the worm frequently -carried a portion of the upper tenacious clay through the softer strata -beneath, and brought it up again. The tenacious clay might have been -called London clay, but no value was attached to that particular -designation; they cared little in engineering for its denomination, -provided it was of a good tenacious quality. This mistake in terms -(supposing it to have occurred) could not have had any influence on -after proceedings; for, before the Tunnel was far advanced, he conducted -with great care a series of borings extending across the Thames, and, as -he used improved tools and worked through tubes, the holes were kept so -dry that a candle was frequently lowered down to the bottom in order to -see the amount of infiltration. By this means he was enabled to -construct a correct section of the bed of the Thames at that spot, -showing every layer of shells and gravel as well as every variation of -the surface of the silt, &c. He entered more at length into these -details than might perhaps appear necessary, because he felt it was -incumbent upon those who had the conduct of works to show that they did -not proceed so ignorantly or so recklessly as had been assumed, in the -design or execution of large undertakings.' - -[9] The paragraphs in small type, without any reference, are from Sir -Isambard's journals. The sentences inserted at the side are his marginal -summary. Occasionally a few words are added (in square brackets) by way -of explanation. - -[10] The shaft subsequently made on the Wapping shore was sunk to its -full depth without any under-pinning. - -[11] Professor Rankine, in his work on _Civil Engineering_, p. 599, -describes the Thames Tunnel works under the significant heading -'Tunnelling in Mud.' - -[12] _Proceedings Inst. C. E._ i. 34. The circumstances which led Sir -Isambard to conceive the idea of a shield, and the earlier designs he -made for it, are described, with illustrations, by Mr. Law, pp. 7-10. - -[13] Mr. Law's memoir contains a detailed description of every part of -the shield, illustrated by careful drawings. - -[14] Mr. Beamish had joined the works on August 7. - -[15] On November 20 Mr. Brunel mentions in his diary that he had 'passed -seven days out of the last ten in the Tunnel. For nine days on an -average 20-1/3 hours per day in the Tunnel and 3-2/3 to sleep.' - -[16] On the previous day Mr. Brunel had been formally appointed resident -engineer. - -[17] Mr. Gravatt had been appointed an assistant engineer six months -before. - -[18] Sir Isambard's journal of this eventful night consists--as he was -not himself present--of Mr. Beamish's journal, with a few words in warm -commendation of that gentleman's 'judgment, coolness, and courage,' -followed by observations upon the stability of the shield. He then gives -a statement made by Mr. Gravatt, and taken down in shorthand. No -extracts are given in the text from Mr. Beamish's narrative, as he has -already inserted it in a condensed form in his _Life of Sir Isambard -Brunel_, pp. 244-248. - -[19] Mr. Michael Lane, at this time foreman bricklayer, became one of -Mr. Brunel's most valued assistants, and was employed by him on the -Monkwearmouth Docks and the Great Western Railway. After filling various -posts in the service of that company, he was in 1860 appointed their -principal engineer, an office which he held till his death, in February, -1868. - -[20] On this occasion an amusing incident occurred. Mr. Brunel was -exceedingly unwilling to permit his visitors to make this expedition -into the arch; but on the assurance that they could all swim perfectly -well, he consented to take them, with the understanding that, if he -jumped overboard, they were immediately to follow his example, and swim -after him to the shaft. While they were in the arch Mr. Brunel (as Sir -Isambard mentions) fell overboard. As soon as he recovered himself, and -turned to swim back to the boat, he remembered that he had unwittingly -given to his companions the signal to jump out into the water. He was -much amused, on looking up, to see that they were not swimming after -him, but were still sitting in the boat clinging to the gunwale, with -faces expressive of blank despair. - -[21] Mr. Brunel's comment in his diary is as follows:--'Without -ascribing any particular merit to myself, I cannot help observing, for -my future guidance, that being alone, and giving few but clear orders, -and those always to the men who were to execute them, I succeeded in an -operation not altogether mean, and which a very trifling want of -precaution or order might have caused to be a total failure.' - -[22] On January 15, 1828, the Directors of the Thames Tunnel Company -passed the following resolution, which they ordered to be advertised in -the _Times_, _New Times_, _Herald_, _Ledger_, and _Courier_:--'That this -court, having heard with great admiration of the intrepid courage and -presence of mind displayed by Mr. Isambard Brunel, the company's -resident engineer, when the Thames broke into the Tunnel on the morning -of the 12th instant, are desirous to give their public testimony to his -calm and energetic endeavours, and to that generous principle which -induced him to put his own life in more imminent hazard to save the -lives of the men under his immediate care.' - -[23] The Thames Tunnel was not successful as a commercial undertaking; -but it has always been considered, especially by foreigners, one of the -most interesting sights in London, and has been visited by several -millions of persons. In 1865 it was purchased by the East London Railway -Company, and trains now (March, 1870) run through it. The possibility of -using the Tunnel as a railway had been considered in Mr. Brunel's -lifetime, and the idea was approved of by him. - -[24] This description is based on the translation given by Mr. Drewry -(_Suspension Bridges_, London, 1832, p. 75), from the _Memoire sur les -Ponts Suspendus_, by M. Navier (Paris, 1823, p. 49). M. Navier saw the -bridges when they were erected at Sheffield in May 1823. - -[25] The dimensions of these designs were as follows:-- - - (_a._) Length of floor 890 feet. - Distance between points of suspension 980 " - Length of chain 1,300 " - With a capacity to bear excessive load of 650 tons. - - (_b._) Length of floor 916 feet. - Distance between points of suspension 1,160 " - Length of chain 1,468 " - With capacity to bear excessive load of 650 tons. - - -[26] On plate I. is given (fig. 1) a facsimile on a smaller scale of the -drawing sent in by Mr. Brunel for the last-mentioned (_b_) of these two -designs. - -[27] See below, p. 60. - -[28] See above, p. 42. - -[29] The dimensions proposed in this design were as follows:-- - - Distance between points of suspension 600 feet. - Versed sine 60 " - Width of roadway 32 " - - -[30] A few days before this ceremony, an iron bar, 1-1/2 inch diameter, and -about 1,000 feet in length, was hung across the valley from Clifton -Rocks to Leigh Down, to facilitate the works. It was traversed by a -basket pulled by ropes. The first few journeys of this machine were -somewhat perilous. It was intended that Mr. and Mrs. Brunel should be -the first passengers; but, when all was ready, one of Mr. Brunel's -assistants started on a clandestine trial trip, and owing to a bend in -the bar, the basket stuck half way, and the mast of a passing steamer -caught in the rope. The rope was however cut, and he was drawn back. -When the apparatus had been put to rights, on another occasion, when Mr. -Brunel was in the basket, it got jammed, and he had to climb up the -connecting link and get upon the bar, before he could release the -basket. - -[31] - - Span 702 feet 3 inches. - Versed sine 70 " - Roadway above high-water 248 " - - -[32] Plate I. fig. 2 (p. 49), shows an elevation of the bridge according -to the designs on which it was commenced. - -[33] See Mr. Brunel's remarks:--_Proceedings Inst. C. E._ for 1841, pp. -78, 79. - -[34] Rollers on an arched surface had been used previously in several -bridges. - -[35] The chains were used in the construction of the Saltash bridge. - -[36] Speech of the Chairman, the late Captain Mark Huish, at the first -general meeting, August 2, 1861. - -[37] Some re-arrangement of Mr. Brunel's design was rendered necessary -in order to adapt the Hungerford bridge chains to the Clifton bridge, -and there are three chains instead of two, as in Mr. Brunel's design. -The platform is stiffened by wrought-iron girders instead of by timber -trussing, and the whole bridge is stiffened transversely by the -wrought-iron girders at the sides, which are connected throughout by -diagonal bracing. The clear width of the bridge is 30 feet, 5 feet less -than originally intended. It should be added, that no attempt has been -made to complete the towers according to Mr. Brunel's architectural -designs. - -[38] A graphic account of this famous parliamentary contest will be -found in the third volume of Mr. Smiles' _Lives of the Engineers_, -chapter xi. - -[39] See Mr. Smiles' _Life of George Stephenson_, p. 325. - -[40] See Mr. Smiles' _Lives of the Engineers_, vol. iii. chap. xv. - -[41] By means of the railway (it was said) goods would be conveyed with -ease from London to Reading in _three or four hours_, and from Bath to -Bristol in _one hour_. - -[42] During Mr. Stephenson's cross-examination, several questions were -put to him as to the dangerous consequences which might be expected to -result from travelling through a tunnel a thousand yards long. At length -he lost all patience at the ignorance displayed by the questions put to -him by counsel, and the following passage of arms took place:-- - -'_Mr. Stephenson._ I wish you had a little engineering knowledge--you -would not talk to me so. - -_Counsel._ I feel the disadvantage. - -_Mr. Stephenson._ I am sure you must.' - -In other parts of the engineering evidence there are some statements -which read strangely enough at the present day, as for example the -following: 'The noise of two trains passing in a tunnel would shake the -nerves of this assembly. I do not know such a noise. No passenger would -be induced to go twice.' - -[43] At this time the Lords' committees were open to all peers who chose -to sit on them, and it was not considered indecorous for peers who had -not attended any of the previous sittings to vote on the division. - -[44] The Great Western Railway was constructed with but few deviations -from the line sanctioned in 1835. The only alteration of any importance -was at the London end, where, by an Act passed in 1836, the line was -taken to Paddington, instead of joining the London and Birmingham -Railway near Kensal Green. This change of plan was rendered necessary by -reason of a difficulty having arisen between the two companies as to the -terms of their agreement, and not, as has been often stated, in -consequence of the adoption of the broad gauge on the Great Western -line. - -[45] Sir William Armstrong's hydraulic machinery at Paddington is -described by him in a communication printed in the _Report of the -British Association_ for 1854, p. 418: 'I have also applied it [water -pressure machinery] extensively to railway purposes chiefly under the -direction of Mr. Brunel, who has found a multitude of cases involving -lifting or traction power in which it may be made available. Most of -these applications are well exemplified at the new station of the Great -Western Railway Company in London, where the loading and unloading of -trucks, the hoisting into warehouses, the lifting of loaded trucks from -one level to another, the moving of turn-tables, and the hauling of -trucks and traversing machines are all performed, or about to be so, by -means of hydraulic pressure supplied by one central steam engine with -connected accumulators.' - -[46] See p. 104. - -[47] No copy of this report can be found; but documents of subsequent -date sufficiently indicate the nature of the arguments Mr. Brunel used -in it. - -Mr. Brunel had about this time given much attention to the principles of -wheel carriages, as is manifested by an interesting article 'On Draught' -written by him for the work on 'The Horse,' published by the Society for -the Diffusion of Useful Knowledge. - -[48] With regard to this point, Mr. Brunel afterwards admitted that he -had held a mistaken opinion. In speaking of his reasons for adopting the -narrow gauge on the Taff Vale Railway in 1838, he said before the Gauge -Commission:--'One of the reasons, I remember, was one which would not -influence me now; but at that time I certainly assumed that the effect -of curves was such, that the radius of the curve might be measured in -units of the gauge, in which I have since found myself to have been -mistaken.' - -[49] See Mr. Brunel's report of August 1838, printed in Appendix I. p. -528. - -This plan was never adopted, as it was found desirable upon the broad -gauge to use still wider carriages overhanging the wheels; but advantage -was taken of the broader base to use wheels of greater diameter. -However, in the saloon carriages, where ease of travelling was the chief -object aimed at, the bodies were placed within the wheels. - -[50] In the course of constructing the earth-works of a railway, the -contractors were accustomed to lay down _temporary ways_ or lines of -rail, for the earth waggons to travel upon. When these were done with, -the proper road for the trains was laid down; and this, to distinguish -it from the former one, was called the _permanent way_. - -[51] See Wood _On Railways_, 3rd. edit. 1838, p. 151. - -[52] A full description of the original road of the Great Western -Railway, communicated by Mr. Brunel, will be found in Wood's _Treatise -on Railroads_, 3rd edit. 1838, p. 708. - -[53] At this time Mr. Brunel was confined to the house by the effects of -his accident on board the 'Great Western' steam-ship (see p. 242). Had -he been on the spot, he would have been able to give the work careful -consideration during its progress, and to judge of the expediency of -proceeding with the plan. - -[54] The continuity of the timbers diminishes the risk of trains leaving -the line from small imperfections in the permanent way. And, should a -train leave the rails, the injury to the carriages and to the road is -generally less serious than it is when the wheels of a carriage off the -rails come into repeated and violent contact with the cross sleepers. -Instances have frequently occurred where carriages which have left the -rails have run considerable distances on the longitudinal timbers -without injury. - -[55] This experiment excited the greatest interest, and it was long -afterwards related how Mr. Brunel, by the stroke of a hammer, had -knocked to pieces the scientific deductions of Dr. Lardner, who, as was -well known, had prompted Mr. Wood's decision in this matter. - -Mr. Brunel was so much impressed with the great influence which the -operation of the blast-pipe had on the working of the locomotive that he -afterwards investigated the whole subject, and made further experiments -to determine whether or not it might be expedient to abandon the steam -blast, and to maintain the draught in the chimney with a fan worked by a -rotary steam jet. - -[56] The inconveniences of a break of gauge had already been brought -into notice. One of the narrow-gauge companies, the Midland, worked two -existing lines of railway, one between Birmingham and Gloucester, laid -on the narrow gauge, and another between Bristol and Gloucester, on the -broad gauge; and thus there was a break of gauge at Gloucester. - -[57] It should, however, be added, that the Commissioners had stated in -the body of their report: 'We feel it a duty to observe here, that the -public are mainly indebted for the present rate of speed, and the -increased accommodation of the railway carriages, to the genius of Mr. -Brunel and the liberality of the Great Western Company.' - -[58] These experiments will be found in the Appendix to the Report of -the Commissioners of Railways, respecting railway communication between -London and Birmingham (ordered to be printed May 22, 1848). - -[59] This was fully borne out afterwards, the express trains running in -the same time, 3 hours, over both routes, though the length of the -broad-gauge line was 129 miles, as against 113 of the narrow. Similar -favourable results have been since exhibited in the competition between -the broad and narrow gauge lines to Exeter. - -[60] Among many important advances in railway travelling made on the -Great Western Railway, it may be mentioned that it was on this line that -express trains running long distances without stopping were first -introduced; and that, in 1845, within about a year of the completion of -the line to Exeter, express trains ran from London to Exeter, 194 miles, -in 4-1/2 hours. This rate of travelling, which was accomplished without -difficulty by the broad gauge in its early days, has scarcely been -exceeded since on any railway. - -[61] Even in the locomotives when of equal power, Mr. Brunel calculated -that the extra weight was not more than about 500 lbs. - -The extra cost of the Great Western Railway was only, including land, -from 300_l._ to 500_l._ per mile, or less than 10 per cent. of the -whole; although Mr. Brunel had taken advantage of the broad gauge to get -carriage bodies 2 feet wider than was then usual. - -The wide carriages and waggons were found less costly than the narrow -ones in proportion to the load they carried. - -[62] The apparatus patented in 1839 by Mr. Samuel Clegg and Messrs. -Jacob and Joseph Samuda, and improved from time to time by them, was -that adopted in almost all the attempts made in this country to -introduce the Atmospheric System. In reckoning up the force which was -available for mastering the practical difficulties of the undertaking, -the death, in 1844, of Mr. Jacob Samuda must be considered to have been -to his brother, and to all others concerned, a great and irreparable -loss. - -[63] A considerable amount of engine power was necessarily consumed in -exhausting the tube before the passage of the train commenced; and it -might at first sight appear that this work was wasted, and that it was -only the work which the engine performed during the passage of the train -which was useful in traction. This, however, was not the case; for, as -was admitted by the more scientific of the opponents of the Atmospheric -System, the power employed in anticipatory pumping was work legitimately -stored up and re-delivered in relief of the engines during the passage -of the train. A waste of power incidental to the Atmospheric System was -indicated by the heat of the air which was delivered by the exhausting -pumps. This waste, however, amounted on the average to only 10 per cent. -of the total work done. A further source of waste of power was the -friction of the air passing along the tube to the exhausting pumps; this -waste was found to amount, on the average, to from 10 to 15 per cent. of -the total work done. - -[64] This was almost the only case in which Mr. Stephenson approved of -the application of the System. - -Before the Croydon and Epsom Committee, in answer to the question, 'Does -the Atmospheric railway give you any power of using practically and -usefully steeper inclines than the locomotive railways?' Mr. Stephenson -said, 'Yes, I think it does, but still at a very inordinate loss of -power; still it is within the scope of the Atmospheric System under -particular circumstances. I remember a case where it might be -advantageous. Mr. Brunel went to Italy for the purpose of laying out a -line there, and from Genoa over the Apennines he had to form a line; it -would probably rise 15 or 20 miles at 1 in 100 or 1 in 60 or 70. Where -there is that continuous line of ascent, where no stoppages are -required, where the locomotive is totally inapplicable, there I can -conceive nothing more eligible than the Atmospheric plan' (p. 80). - -[65] The length of the line was 52 miles, but as it was considered that -auxiliary stationary power would in any case be necessary on the 10-1/2 -miles of very steep inclines, the cost of the Atmospheric apparatus is -taken on 41-1/2 miles. - -[66] It must be remembered that beyond the South Devon Railway was the -projected railway through Cornwall, which, with its long and heavy -gradients, was, in all its features, even more suitable than the South -Devon for the application of the Atmospheric System. Had that system -succeeded, and been introduced on the Cornwall Railway, a very great -saving might have been made in the cost of the works of this line. - -[67] _I.e._ before the Croydon and Epsom Committee. See above, p. 138. - -[68] It will be found on pp. 35-52 of the Minutes of Evidence taken -before the Atmospheric Committee (ordered to be printed April 24, 1845). - -[69] This appeared with sufficient clearness from the general comparison -between vacuum, weight of train, and speed. The exact appropriation of -the force employed was shown by some dynamometric experiments made on -the line. - -The highest speed recorded was 68 miles per hour, with a train of 28 -tons, the speed averaging 64 miles per hour for four level miles of the -line, the vacuum being 16 inches. This speed should have exhibited a -resistance of about 21 lbs. per ton, or 588 lbs., as the running -resistance or friction, and 645 lbs. for the resistance of the air; in -all 1,233 lbs. Now, the pressure due to 16 inches of vacuum on the -piston is 1,390 lbs., which gives 157 lbs. as the friction of the -piston; a result which corresponds sufficiently well with a direct -dynamometric experiment. - -Going to the other extreme, there are numerous records of trains of 100 -tons which attained, on a level of four miles in length, average speeds -of from 30 to 35 miles per hour, with 16.5 inches of vacuum, one train -of 103 tons going 32.4 miles per hour with 16.9 inches of vacuum. - -[70] This valve consisted of a number of long delicate blades of spring -steel, arranged parallel to each other, as in a musical box, but with -wider intervals. These plates rested on a series of truly faced bars, -which crossed the end of the air-passage. The slightest pressure -outwards lifted the springs; and as the area of opening was large, a -very free passage was given to the air. On the current ceasing, the -blades instantly, yet without shock, replaced themselves in contact with -the bars, clipping them tightly under a very small reverse pressure, and -effectually closing the passage. Their merit consisted in their being -almost without weight, and thus promptly re-closing the aperture by a -delicate elastic reaction. - -[71] Trains frequently arrived late on the Atmospheric portion of the -South Devon Railway, owing to its being at the end of the long trunk -line from London to Exeter, and having at its other end a locomotive -line contending with very heavy gradients. - -[72] It may be mentioned that, from the date of the abandonment of the -Atmospheric System, he refused to receive any remuneration for his -professional services as engineer beyond a nominal retaining fee. - -[73] See above, p. 138. - -[74] These quantities are the result of the experiments made in -September 1847. They agree with what is now the received opinion of -authorities on train resistances, and represent favourably the case for -the locomotives at the time of Mr. Brunel's report in August 1844. At -the time when Mr. Brunel wrote his report of August 1844, the weight of -a locomotive, as has been said, bore a higher ratio to its power. - -[75] It must be borne in mind that all the inconveniences attending the -use of auxiliary locomotives must be encountered, or else the excessive -dead weight of an engine powerful enough to take a train up the steepest -gradient in a hilly district must accompany it for the whole length of -that part of the line. - -[76] No dynamometer was used in these experiments, but all other -requisite data were recorded with the greatest exactness, and the -horse-power employed may be deduced by means of the scale of resistance -which the subsequent dynamomotric trials supply. Moreover, the result -above arrived at for the consumption of coke is verified by an -examination of published indicator diagrams taken off the same engine on -another occasion. - -[77] It would of course be impossible here to give a description of all -Mr. Brunel's bridges, or even to refer to the most important of them -with that minuteness which would be required if this were a book written -for professional use. The following publications may be -consulted:--Bourne's _History and Description of the Great Western -Railway_, 1846; Brees' _Railway Practice_, 1837; Simms' _Public Works of -Great Britain_, 1838; _Proceedings of Institution of Civil Engineers_, -vols. 14, 25, and generally; Molinos et Pronnier, _Construction des -Ponts Metalliques_, 1857; Humber's _Cast and Wrought-Iron Bridge -Construction_, 1861; and Humber's _Record of Engineering_ for 1866. At -the end of the description of many of the bridges in this chapter a note -has been given of publications in which the bridge has been referred to. - -[78] In the early days of the Great Western Railway special designs were -made for every one of the ordinary bridges over and under the railway; -but when, in consequence of the rapid extension of the Great Western -system, the number of bridges to be designed became very large, Mr. -Brunel had a set of 'standard drawings' prepared and engraved, which -embodied the experience gained, and contained designs suitable for -various situations. The contract drawings were made by adapting to the -particular circumstances of each case the standard drawing which was -most applicable to it. This system, besides securing uniformity of -construction, introduced a considerable amount of economy; since, the -standard drawings being based upon the results arrived at in an -extensive practice, the proper structural arrangements and dimensions -were indicated with far greater accuracy than could be attained in a -reasonable time by an independent calculation in each individual case. - -[79] It was called the 'Wharncliffe Viaduct,' in acknowledgment of the -services rendered to the Company by the late Lord Wharncliffe as -Chairman of the Committee in the House of Lords. Drawings of this bridge -are given in Simms' _Public Works of Great Britain_, 1838, pl. 54, 55, -and 56; and in Bourne's _History and Description of the Great Western -Railway_, 1846. - -[80] At the back of retaining walls, such as the abutments and wing -walls of bridges which were subject to the pressure of earth behind -them, Mr. Brunel introduced what were termed 'sailing courses,' -projecting shelves corbelled out at the back of the wall. The weight of -earth resting on these shelves virtually increased the weight of the -back of the wall, and assisted it in resisting the forward pressure of -the earth. - -[81] During the construction of the bridge a part of the crown of the -eastern arch proved defective, in consequence of the cement in the -middle of the brickwork not having set sufficiently at the time when the -centering was eased. Apprehensions which had been entertained by some as -to the safety of the structure were groundless, for when the defective -part was taken out and replaced, no further trouble was experienced. The -bridge has stood well, and has shown none of those symptoms which an -overstrained structure exhibits. - -[82] Simms' _Public Works of Great Britain_, pl. 57, 58; Bourne's -_History and Description of the Great Western Railway_, p. 36. - -[83] When Mr. Brunel for architectural effect employed Gothic or pointed -arches, he occasionally made the main part of the arch of a form -different from the curve visible on the face, but he more frequently -made it of the same pointed form throughout. In this case he did not -obtain equilibrium by loading the crown, but he kept the line of -pressure sufficiently within the thickness of the arch by strengthening -the haunches. - -[84] Brees' _Railway Practice_, pl. 42. - -[85] There is an illustration of this bridge in Bourne's _History and -Description of the Great Western Railway_. - -[86] Joggles are small pieces of hard wood or cast-iron of rectangular -cross section, placed between two beams, and fitted carefully into -notches cut across them. The beams are then bolted firmly together. The -object is to stop the slipping which would occur between the two -surfaces if the beams were merely laid one on the other and loaded, and -so to make two pieces of equal size act as one of double the depth, and -therefore of four times the strength of a single piece. In 1841 Mr. -Brunel made experiments to satisfy himself of the strength gained by -this method; and he afterwards perfected the arrangement by ensuring an -exact fit in the notches by tightening up the joggles with wrought-iron -wedges. - -[87] A drawing of this bridge is appended to the _Report of the -Commission on the Application of Iron to Railway Structures, 1849_. - -[88] Mr. Brunel, by taking care in his timber structures to distribute -the load uniformly, was frequently able to dispense with costly -foundations. On one occasion a timber viaduct 30 feet high was placed -upon a broad platform resting on an old embankment upwards of 50 feet in -height. A similar arrangement was adopted by him in some cases on slips -in embankments which it would have been uncertain and expensive to make -up with earthwork. - -[89] For a description of this viaduct, see _Proceedings Inst. C. E._, -vol. xiv. for 1854-5, p. 492. - -[90] Mr. Brunel about this time introduced a great improvement in the -manufacture of wrought-iron bolts for bridges, when these, as is usually -the case are screwed at the ends. A screw cannot be made on a bolt -without the metal being cut into to the extent of the depth of the -thread, and the strength thereby considerably reduced. The section, -taken at the bottom of the thread, is much smaller than that of the -bolt; and, moreover, owing to the abrupt change at the commencement of -the thread, the strength is not so great as that due to the reduced -sectional area. The improvement consisted in swelling out the iron of -the end of the bolt where the thread was to be made, so that the -diameter, at the deepest part of the thread, should be fully equal to -that of the bolt. The saving of metal by this improvement, especially in -the case of long bolts, is very considerable. - -[91] An arrangement was introduced by Mr. Brunel to prevent any -disturbance in the permanent way by a settlement of the embankments at -the ends of the viaducts. There were no large abutments and wing walls, -but the end of the viaduct was formed with a queen truss in the parapet, -which rested on a platform on the top of the embankment slope. In any -slight settlement of the earth, the end of the viaduct sunk with it, and -the permanent way was not disturbed. Wedges were provided to raise the -ends of the trusses and readjust their level. This was an important -provision, as it applied to about 60 cases on the Cornwall Railway. - -[92] The simple arrangement of the timber-work was specially arranged -with a view to giving facility for replacing portions of it, should they -decay. - -[93] The viaducts on the Cornwall Railway between Plymouth and Truro are -thirty-four in number. Of these there are nineteen which have from six -to twenty openings, and are from 80 to 153 feet in height. The aggregate -length of these nineteen viaducts is nearly 2-3/4 miles. - -[94] A drawing showing this form of section is appended to the _Report -of the Commission on the Application of Iron to Railway Structures_, -1849. - -[95] The remainder of this letter is printed in Chapter XVI. p. 486. - -[96] Mr. Brunel was thoroughly conversant with the principles of -mathematical analysis, and was able with great readiness to apply it in -practice; but at the same time he preferred, when it was possible, to -use geometrical methods of solution for engineering problems. - -[97] In the note at the end of this chapter mention is made of some -experiments made by Mr. Brunel on riveted joints. - -[98] See above, p. 185. - -[99] A description of this bridge is given in Humber's _Bridge -Construction_, vol. i. p. 228, and vol. ii. pl. 70, 71, 72; Molinos et -Pronnier, _Construction des Ponts Metalliques_, p. 328, pl. 20, 21, 22. - -[100] See _Proceedings Inst. C.E._, for 1847-8, vol. vii. p. 138. - -[101] After some perseverance, Mr. Brunel succeeded in getting these -unusually large links, which were 20 feet long, rolled in a single piece -without welding on the eyes. He had to go down himself to the -manufactory in order to get the men into the way of doing the work. - -[102] See note at the end of this chapter for experiments on ropes and -chains. The crabs were designed and made specially for this duty. Each -had two barrels, grooved to receive the chain, which was passed several -times round both barrels, so as to get sufficient grip; and it was in -this way possible to wind in with the crabs any length of chain without -having to stop to fleet, as would have been the case had a -single-barrelled crab been used. - -These crabs were subsequently used at the floating of the Saltash -trusses, and at the launch of the 'Great Eastern.' - -A similar arrangement was applied in the paying-out machinery of the -Atlantic cable, and is still used for the picking-up gear in the 'Great -Eastern.' - -[103] See _Encyclopaedia Britannica_, 'Iron Bridges,' vol. xii. p. 601; -Molinos et Pronnier, _Construction des Ponts Metalliques_, p. 320, pl. -23, 24, 25. - -[104] These would have been magnificent specimens of timber-work, and a -design for somewhat similar trusses had at one time been prepared for -the Chepstow Bridge. It is worthy of mention that Sir Isambard Brunel at -one time designed a timber arched bridge of 800 feet span to cross the -Neva at St. Petersburg. - -[105] Before the work was begun Mr. Brunel made calculations to -determine whether or not it might be desirable to cross the river with -one span of 850 feet, in order to avoid the great depth at the centre -pier. - -A few extracts from letters relating to bridges of large span will be -interesting: - - 'January 31, 1852. - - 'I have revised my calculation as to a span of 1,000 feet, and find - that even with the loads and limitations of strains which I - adopt--namely a proper thickness of ballast, and a possible load of - a train of engines without tenders, and a limitation under such a - load of 5 tons' strain per square inch, that a span of 1,000 feet - may be made in England of the very best workmanship, and sent out - and erected for I should say safely 250,000_l_., of course a single - way--another 250,000_l_. ought, I should think, to cover the rest - of the bridge. - - I should like to explain to you the mode I should propose for - raising such a bridge, weighing 7,000 tons. - - 'December 1, 1852. - - As you ask me my opinion of the advisability of patenting your - bridge, I give it you; though you will probably be the first person - who will have followed such advice if you do so, and might safely - patent such a novel mode of using advice. - - In my opinion you cannot patent the bridge. Without detracting in - the least from your merit of invention, the form has been so - frequently and exactly applied that no patent could hold. The - Saltash bridge now just advertised for letting is exactly on the - same principle as regards form; and this is so old to my knowledge - that I can claim no invention, and the use of cast iron for such - purpose is also incapable of being patented. There is much that is - good in your bridge, and you deserve credit, but you would find - innumerable claimants to dispute, and successfully, your attempt to - claim a monopoly by a patent--I myself for one. Besides, I see it - published in a book. - - 'May 30, 1854. - - 'As to your present enquiry, I do not think that what I am doing at - Saltash would be applicable in this case; but without being guilty - of great presumption, I think I may say that if the same plan will - not do, it is fair to assume that the same brains which concocted - the plan to suit the difficulties of the Tamar might very likely - find the means of overcoming those of the Severn. - - If I should be able to suggest a feasible plan, and there should be - found people ready to make it, I shall have the satisfaction of - bridging the Severn as well as the Tamar.' - -[106] It has of course been impossible to refer to the points on which -Mr. Brunel was aided, in his different works, by the suggestions of his -assistants; but it may be mentioned here that, as appears from one of -Mr. Brunel's letters, the plan of working under a diving-bell had been -proposed by Mr. William Glennie, his assistant, before he knew that Mr. -Brunel had decided to adopt it. - -Mr. Brunel also mentions in another letter that the 'very simple and -effectual manner' of applying the pneumatic apparatus, by forming the -annular space round the circumference of the bottom of the cylinder, was -suggested to him by Mr. Brereton, when the method of constructing the -cylinder was being finally settled. - -[107] In the _Proceedings of the Institution of Civil Engineers_, vol. -xxi. 1861-2, will be found a paper by Mr. Brereton, giving a detailed -description of the means employed for the construction of the central -pier. - -[108] Shortly after Mr. Brunel's death some of his friends on the Board -of the Cornwall Railway placed the following inscription, in raised -letters, over the lard archways--I. K. BRUNEL, ENGINEER, 1859. - -[109] A portion of the chains used were those which had been made for -the Clifton Suspension Bridge, Mr. Brunel's earliest design. - -[110] Though it is convenient to explain the nature of the strains in -the Saltash bridge as an arch and suspension bridge combined, it is not -intended to imply that there is any virtual difference between this -truss and the one at Chepstow, for in both the strain on the tube -counteracts the strain on the chains, though the one tube is curved and -the other straight. - -[111] Humber's _Bridge Construction_, vol. i. p. 231; vol. ii. pl. 78, -79, 80. - -[112] This load amounted to two and three quarter tons per foot run, in -addition to the weight of the truss. Under this load the central -deflection was about 5 inches. - -The strain on the iron of the tube and of the chains with a load of one -ton per foot run, in addition to the weight of the truss, flooring, and -ballast, is under four tons per square inch. - -[113] The difficult operations of floating and lifting the -superstructures of the Chepstow and Saltash bridges were carried out -entirely by Mr. Brunel and his assistants, there being no contractor -engaged in, or responsible for, the work in either case. - -[114] A photograph taken shortly after the floating of the second tube -forms the frontispiece of the first volume of Humber's _Bridge -Construction_. - -[115] See above pp. 190 and 193. - -[116] It has been observed with much truth that full justice has not -been done to Mr. Brunel's exertions in this department of practical -science.--See 'Address of George Parker Bidder, Esq., on his election as -President of the Institution of Civil Engineers, January 10, 1860.' - -[117] Captain Claxton died on March 27, 1868, in his 79th year. The -manuscript of this and the three following chapters was fortunately -completed in time to be submitted to him. He spared no trouble either in -giving or procuring original documents and other materials for all parts -of this book, in the preparation of which he took the liveliest -interest. - -[118] To enable the ship to resist the action of the heavy Atlantic -waves, especial pains were taken to give her great longitudinal -strength. The ribs were of oak, of scantling equal to that of -line-of-battle ships. They were placed close together, and caulked -within and without before the planking was put on. They were dowelled -and bolted in pairs; and there were also four rows of 1-1/2-inch iron -bolts, 24 feet long, and scarfing about 4 feet, which ran longitudinally -through the whole length of the bottom frames of the ship. She was -closely trussed with iron and wooden diagonals and shelf pieces, which, -with the whole of her upper works, were fastened with bolts and nuts to -a much greater extent than had hitherto been the practice. - -The principal dimensions of the hull and engines are given in the note -to this chapter (p. 245). - -[119] The engines as designed by Messrs. Maudslay were beam engines, -although Mr. Brunel had strongly urged them to adopt the more compact -form of direct-acting engines. They, however, thought it better not to -depart from what was then the usual form. - -[120] _Steam and its Uses_, by Dr. Lardner, 1856. Chapter on 'Steam -Navigation,' section 10. - -[121] 'An exposition of the advantages of the proposed Railway from -Limerick to Waterford.' - -[122] _The Steam Engine: its Application to Navigation and Railways, -with Plain Maxims for Railway Speculators_, 5th edition, 1836, p. 307. - -[123] It is right to add that, according to the report given in the -_Athenaeum_ newspaper of the meetings of the British Association at -Liverpool in September 1837, 'Dr. Lardner addressed the section -(Mechanical) on his old subject, the application of steam to long -voyages. His remarks and calculations were to a great extent identical -with those brought forward by him last year at Bristol, and published -long since in his work on the steam-engine, but the conclusions were -somewhat varied. The Doctor did not now deny that the voyage might be -practicable, but he did not believe that it would be profitable' -(_Athenaeum_, September 23, 1837). Dr. Lardner was answered by several -speakers, and among them by Mr. Guppy, who pointed out in much detail -the unreliable character of Dr. Lardner's data; while nothing was -suggested about commercial profits or subsidies. It may therefore be -inferred that Dr. Lardner's arguments as to the consumption of fuel -remained the same, although he may have abandoned the conclusion which -legitimately followed from them--namely, that the long voyages were -practically impossible. - -The Report in the _Bristol Mirror_ newspaper of the same date (copied -from the _Liverpool Standard_) is as follows:--'Dr. Lardner's speech was -little beyond a repetition of his discourse last year in Bristol, -re-published by him in the _Edinburgh Review_. The voyage to America by -steam he treated as practicable, but so uncertain as to render a -profitable result hopeless.... During nearly all the year there was an -adverse west wind, and the Gulf Stream was to be avoided.' - -[124] She had only _seven_ passengers on board; fifty, it is stated, -were deterred from going in her by hearing of the fire. - -[125] These engines were to have had two cylinders of 88 inches -diameter. - -[126] It is interesting, in connection with this subject, to mention the -following circumstance. At Mr. Brunel's recommendation, Mr. Humphrys -consulted Mr. James Nasmyth as to the best means of forging the large -paddle-shaft; as they could not get any manufacturer to undertake it. To -accomplish this forging Mr. Nasmyth designed his steam-hammer, and -though it was not then erected in Bristol, in consequence of the -alteration of the form of the engines of the 'Great Britain,' it soon -afterwards came into general use. - -[127] In the Minute Book of this date it is mentioned as a reason for -postponing any decision on the subject, that Mr. Brunel was making -'final,' and afterwards 'further,' experiments. - -[128] See Mr. Guppy's paper, printed in the _Proceedings of the -Institution of Civil Engineers for_ 1845, p. 151. - -[129] This report is printed in Appendix II. p. 539. The paragraphs in -which Mr. Brunel describes the advantages of the screw propeller will be -found at page 552. - -[130] A description of Mr. Humphrys' trunk engines is given in -Tredgold's work on the steam engine (ed. 1838), p. 390. - -[131] The balanced rudder, which is peculiarly applicable to screw -ships, has encountered much opposition; but it has lately been -successfully introduced by Mr. E. J. Reed, C.B., into vessels designed -by him for the Royal Navy. - -[132] It maybe convenient here to state that the dock in which the -'Great Britain' was built led into the Floating Harbour, which is a -portion of the channel of the river Avon closed in. The Floating Harbour -communicates through the Cumberland Basin with the river. - -[133] One of the consequences of the publication of this report was, -that Mr. Brunel received so many letters containing suggestions for -lifting and floating the ship, that he was obliged to have a circular -letter printed declining assistance; and more than four hundred letters -were also received by the Company's secretary. - -[134] 'The "Great Britain" Steam-Ship. Extracts from the letters of -Captain Claxton, R.N., to I. K. Brunel, Esq., and the Directors. -Bristol, 1847.' - -Mr. Bremner's apparatus is also described in a paper read by him at the -Institution of Civil Engineers, and printed in the twenty-first volume -of the _Transactions_, p. 160. - -Accurate illustrations of the break-water and floating apparatus will be -found in the _Illustrated London News_ of August 21, 1847. - -In publishing the correspondence to which reference has been made, the -Directors acknowledge their obligations to all concerned in the arduous -task of saving the 'Great Britain;' and they add--'to Mr. Brunel above -all their thanks are most due, for opening their eyes to what might be -accomplished, and for taking upon himself the responsibility of her -release, provided that Captain Claxton was employed to carry out his -views.' - -[135] Sir E. Parry was at that time Controller of Steam Machinery, and a -warm supporter of those who desired to make a fair trial of the screw -propeller. - -[136] Bourne, on the _Screw Propeller_, ed. 1867, p. 263. - -[137] The records of these trials, found among Mr. Brunel's papers, show -results which coincide in all material points with those given by Mr. -Bourne at p. 284 of his work on the _Screw Propeller_, ed. 1867. - -[138] Bourne, Appendix, p. xxxiii. - -[139] The letter to Mr. Guppy of August 1843 (given above, p. 259) -contains a reference to some of Mr. Brunel's ideas upon iron -shipbuilding, subsequent to the date of the design of the 'Great -Britain.' - -[140] Extract from a memorandum by Mr. Brunel (dated February 25, 1854) -on the early history of the great ship. - -[141] So Mr. Brunel wrote to the secretary when excusing his own absence -from the meeting on account of illness. - -[142] Mr. Brunel concludes this report by indicating the best mode of -contracting for the construction of the ship and engines, and suggests -that an examination should be made of the river Hooghly. - -[143] From the great length of this report it has been necessary to omit -the less important paragraphs. - -[144] The passages which are omitted refer to the relative cost and -merits of the different tenders. - -[145] Two years later Mr. Brunel spoke of the success of the screw -engines as 'a most grave question upon which hangs I fear to think how -much.' - -[146] Mr. Geach was one of the most zealous friends of the great ship. -His death, within a year after the commencement of the work, was the -first of her many misfortunes. - -[147] Stringent conditions as to jacketing were introduced into the -contracts; but they were not enforced by Mr. Brunel, in deference to the -strong objections urged by the makers. He much regretted this -concession. - -[148] The destination of the ship as proposed at this time was -Australia. - -[149] The power of blowing off the steam without noise is of great -importance, and Mr. Brunel made many experiments on the point. The noise -of the steam blowing off, when the engines of a ship are stopped for -fear of an impending collision or other accident, is so great, that it -is almost impossible to hear any orders that may be given. - -[150] The screw propeller of 'Agamemnon' was broken in a trial trip -outside Plymouth Sound, on November 9, 1853; and the result was that, -from not having efficient governors, the engines flew round at an -alarming speed. - -[151] Mr. Russell's works. The ship was built in a yard immediately -adjoining them. - -[152] See, for example, an article in the _Quarterly Review_ of March -1856, entitled 'The Triton and the Minnows.' - -[153] It must be remembered that this report describes the ship as she -was at that time designed by Mr. Brunel. - -[154] Extract from memoranda of October 5, 1855:-- - -'By constant observation, to lay down position and course of ship, and -correct compasses. - -'To record speed of ship through water by logs. - -'Revolution of engines. - -'Force and direction of wind. - -'Draught and trim of ship, sails carried, &c. - -'Temperature and peculiarities of sea water. - -'As the result of these observations, to plot down hour by hour the -position of the ship, to compute the speed, variations of compass, the -direction and force of current, and true direction and force of the -wind.' - -[155] Mr. Brunel also proposed to have charts prepared for the route of -the great ship to Australia and Calcutta, similar in character to some -which were made under his directions for the route of the 'Great -Western' to New York, which he described as follows:-- - -'When we started the "Great Western" to New York, I had a chart drawn -and engraved of the sea (that is, the lines of latitude and longitude, -and the bearings of the compass, and the coast and soundings) on a -cylindrical projection of a great circle from Bristol to New York; and -we found it very useful for the captain to _see_ his great circle -sailing, and to see how much he was deviating from it.' - -[156] Captain Harrison's command of the 'Great Eastern' after she left -the river was unhappily of but short duration, as he was drowned by the -accidental upsetting of his boat in Southampton Water on January 21, -1860, four months after Mr. Brunel's death. - -[157] With this paper Mr. Brunel enclosed a letter, in which he points -out with great earnestness the responsibility of his own position. - -After calling the Directors' attention to the important step they were -about to take, he proceeds:-- - -'I am not pointing out a danger without being prepared to propose a -remedy. The same man who, after he has been selected and appointed on -account of his previous character as a sailor, and as an experienced -naval man, would probably feel disposed to reject advice coming from -those who do not profess to be sailors, and to resist directions which -might appear to him as trenching upon his authority, or as implying -doubts of his ability, could have no such feeling (if he is a sensible -man and fit for the position) if his attention had been drawn to these -views before his appointment, and if he accepts the trust reposed in him -on the understanding that he is expected to pay attention to these -opinions, and if, as I shall urge upon the Directors to ascertain, he -entertains no objection to the adoption of them, and agrees to follow -the principles of action which I hope to induce the Directors to adopt -as rules in the navigation of the ship. - -'I propose therefore to lay before the Directors the result of my -anxious consideration of this subject, to urge upon them the adoption of -my views, and, if they adopt them, to urge that they should make it a -condition in the selection and appointment of a commander that such -views are approved of and adopted by him. - -'This is a strong and plainly stated request, but not more strongly put -than I feel that the occasion requires. - -'I have an immense stake in the success of this enterprise. I do not -refer merely to my pecuniary investment; but, as affecting my -professional reputation, my stake is much deeper; as, although I was -accidentally led by circumstances into proposing the plan we have -adopted, and the Company was not originally formed to carry it out, and -although the plan when proposed was well weighed and considered by men -competent to judge, at all events, upon the prospects as a commercial -speculation, and although it was adopted by them, and therefore they -must share in the responsibility, and although many may share with me in -the credit of our success; yet there is no doubt that I should have to -bear solely and very heavily the blame of a failure. On this ground -alone, therefore, the Directors, I am sure, will willingly allow me to -urge my views strongly, and will excuse the length at which I do so. But -I shall rely upon satisfying them that my views and opinion should -command their concurrence on their own merits; and with this preface, -which has already reached an undue length, I will lay before them a -paper on the subject, most of which has been written for some time in -anticipation of the present circumstances, and having been thus written -at different periods is, I fear, somewhat disjointed, and wanting in -arrangement, and therefore much longer than it might have been.' - -[158] Shortly after the publication of this report, Mr. Brunel received -a letter from Mr. G. W. Bull, of Buffalo, U.S.A., encouraging him to -adopt the plan of launching sideways, as that was the way in which the -large steamboats of the American lakes were launched. In the course of a -correspondence which ensued, Mr. Bull gave much information as to the -manner in which these launches were effected. He advocated a free launch -for the 'Great Eastern.' - -[159] For an account of this and other experiments and observations on -friction, see note A at the end of this chapter. - -[160] The power mentioned here as applied for starting the ship was two -hydraulic presses, to overcome adhesion at the first start. The river -tackle was relied on to overcome the friction. - -[161] See below, note A, p. 389. - -[162] The reason for stopping was lest the ship should float at high -water during the night. - -[163] It remained a doubtful point whether or not the bow cradle was -stopped by the brakes. Subsequent experience favoured the opinion that -it had stopped of itself. - -[164] The ship had always been spoken of as the 'Great Eastern,' and -this name was specially agreeable to Mr. Brunel. It was not a point on -which he set much store, but his views were pretty well known; and, as -the name had not been of his choosing, but had rather grown out of the -name of the Company, and the natural association of ideas with his first -ship, the 'Great Western,' it might reasonably have been supposed that -it would have been adopted. But some fastidious person suggested that -the name was objectionable, as consisting of two adjectives. A list of -names was prepared and submitted to Mr. Brunel on the day of the launch -at the moment when he was busiest. He said off-hand that they might call -it 'Tom Thumb' if they liked. The Directors, however, selected the name -'Leviathan,' and so the ship was christened. The new name never stuck to -the ship, and she was registered as the 'Great Eastern.' - -[165] The action of an hydraulic press is limited to the length of -stroke of the ram. Hence, as soon as the ship moved a distance equal to -the length of the stroke, it became necessary to relieve the water -pressure in the cylinder, to pull back the ram into it, and to insert -between the ram of the press and the cradle an additional length of -timber. This operation of pulling back the ram and putting in another -length of timber was called 'fleeting' the press, a term used in many -mechanical operations when the motive arrangements are reinstated in -their primary position ready for a further advance in the work. - -[166] On this occasion Mr. Brunel had his way, and there were not a -dozen spectators in the yard. - -[167] See note A at the end of the chapter. - -[168] At this time the friction when the ship was in motion was not much -greater than it had been on previous occasions; but, the adhesion being -greatly increased, a large excess of power became stored up in the -elasticity of the abutments and the chains. This excess of power, on the -ship commencing to move, discharged itself in giving her velocity, and -therefore she moved by short slips, instead of by a gradual motion, as -had been the case previously, when the resistance due to friction and -that due to adhesion had been more nearly equal. For observations on the -friction, see note A at the end of the chapter. - -[169] Mr. Stephenson went with Mr. Brunel into all the facts relative to -the operations and all the experience gained therefrom, and examined -carefully the investigations which had been made by means of -self-recording apparatus, and which showed that the friction diminished -as the velocity increased. So struck was Mr. Stephenson at these results -that he urged Mr. Brunel on no account to neglect having the brakes -properly attended to; lest the great adhesion should cause a large -amount of stored-up power, which might give the ship such a velocity -that the force of gravity might exceed that of the friction. The brakes -had not been hitherto neglected; but, in conformity with Mr. -Stephenson's suggestion, it was thenceforward made a rule that, when a -moderate amount of slack had been overhauled from the drums, the brakes -should be put down, on a signal being given that the pressure in the -presses was rising. - -[170] Mr. Brunel received a great many suggestions for launching the -ship. Puncheons, gas, artillery, and especially levers, were among the -appliances recommended. With the desire of behaving civilly to -well-meaning persons who were wishing to do him a service, Mr. Brunel -adopted a plan similar to that which he had found useful when the 'Great -Britain' was on shore. He had a circular letter printed, thanking his -correspondents for their suggestions, but saying that the number of such -communications had become so great that it was impossible for him to do -more than cause the receipt to be acknowledged, with thanks for the -intentions of the parties writing. - -This plan had, however, the effect of increasing the number of his -correspondents, as several of them wrote a second time to express their -regret that their letters had had no better effect than to be classed -with the numerous communications which Mr. Brunel said he had received -on the same subject, which had seemed unworthy of his notice; and they -explained that though other people's schemes were, no doubt, worthless, -still that their own, if adopted, would launch the ship. - -[171] The number of the presses being almost doubled, but the resistance -of the ship not being much greater than before, the elastic compression -of the abutments was less than it had been previously, so that when the -ship moved there was much less work stored up to give it velocity; -therefore the slides were shorter than they had been before. - -[172] Among the many congratulations which Mr. Brunel received on the -completion of the launch, there was perhaps none which pleased him more -than the following letter from Mr. Robert Stephenson, who had been -prevented by illness from being present at the concluding operations, -the critical character of which he had fully appreciated:-- - - - February 1, 1858. - - MY DEAR BRUNEL,--I slept last night like a top, after I received - your message. I got desperately anxious all day, but my doctor - would not permit me to venture so far away as Millwall. - - I do, my good friend, most sincerely congratulate you on the - arrival of the conclusion of your anxiety. - - Yours sincerely, - - ROBERT STEPHENSON. - - - - -A letter from Mr. Brunel to his friend Mr. Froude, describing the -floating, is given in note B to this chapter. - -[173] The principal dimensions of the ship and engines are given in the -note to this chapter, p. 416. - -[174] During the last-mentioned voyage, returning from Quebec, a -north-easterly wind blew with a velocity of from 30 to 40 miles an hour. -For the first 24 hours the ship paid no attention to the sea; the next -day, the wind remaining the same, but the sea having got more swell on, -the ship began to roll slowly and sedately, the rolls gradually -increasing up to about 9 degrees on either side of the perpendicular, -and dying out again, and then recommencing. - -[175] Between the screw and the rudder was what was termed the after -stern-post, which had no duty to perform except to steady the heel of -the ship, into which the rudder was stepped. - -[176] Before the ship was finished, Mr. Brunel had her stability and -rolling carefully investigated. Calculations were made to ascertain the -position of her centre of gravity and the other necessary elements for -determining her stability and period of rolling. - -He also had a model made, with arrangements for altering the levels of -weights placed inside. By this means the results of the calculations -were verified. It was determined that the ship would make a single roll -from one side to the other in about six seconds. While she was in the -Thames a steamer struck the hulk alongside and gave the great ship a -slight impulse. Mr. Brunel, who was on board, took advantage of the -opportunity to observe the period of the roll she made, and was pleased -at finding it agree with the calculated period. It is to the -investigations initiated at that time by Mr. Brunel that are due the -great steps since made in the knowledge of the laws which govern the -rolling of ships. Had Mr. Brunel lived he would no doubt have taken the -same pains to record the rolling of the 'Great Eastern' as he had in the -case of the 'Great Western' when, in 1839, he sent an assistant to -America and back, who took observations of the rolling and pitching of -that vessel in several voyages. These observations were made by a simple -angle-measuring instrument, adjusted by the visible level line of the -horizon, and not by the fallacious method of noting down the swings of a -pendulum. - -The 'Great Eastern' remains almost perfectly steady in ordinary rough -seas. When the seas become very long, so that their period is nearly the -same as that of the ship, she rolls; though the number of degrees on -either side of the perpendicular is not large. By stowing the weights of -cargo high in the ship, the tendency to roll has been much diminished, -and when engaged in cable laying, with the enormous weights in the cable -tanks all placed above the lower deck, she is remarkably steady. - -[177] _History of the Atlantic Telegraph:_ New York, 1866. - -[178] It may be desirable to give a short explanation of these works, -which consisted principally of a sluice, a trunk, and a drag-boat. - -The Sluice was made in the abutment of Prince's Street Bridge, and was -intended to create a scour after the water had been let off from either -side of the float, the opening at the bridge being closed by a caisson -which had long been in use when (as was formerly the case) the upper -part of the float was scoured through Bathurst Basin. - -The Trunk, near the entrance from Cumberland Basin, is a wooden culvert -between the floating harbour and the river. As much of the mud as could -be dragged there was deposited at the entrance of the trunk, and, when -the tide was low in the new channel of the Avon, sluices were opened, -and the water rushed through from the floating harbour, carrying the mud -with it. - -The Drag-Boat was fitted with a steam-engine which worked a large -windlass with three compartments, round two of which chains were passed -and fixed to posts on the quays, and the boat was dragged backwards and -forwards. The third compartment of the windlass worked a chain which -elevated or depressed a scraper, attached to a long pole at the stern, -and secured from swerving by a chain-bridle which passed under the boat. -The scraper stirred up the mud, and deposited the more solid parts at -the entrance of the trunk. - -Mr. Brunel also desired that the float boards of the Neetham Dam should -be put into proper working order; and that they should be altered so -that, in times of land floods, the whole or a considerable portion of -the excess of water should be retained, and passed through the feeder; -and that even the water of spring tides should be allowed to pass the -dam, and then be stopped back for the same purpose. - -[179] The advantage of forming an air-chamber in the lower part of the -gate, and allowing the water to enter above it, is that when the size of -the air-chamber is properly adjusted to the weight of the gate, there -need not come on the wheels, while moving, more than a trifling amount -of weight. - -[180] The arrangements of a buoyant gate have been explained above, p. -429. - -[181] In the year 1856 and afterwards, Mr. Brunel was engaged in -improving the navigable channel of the river Neath, at its embouchure -into the Bristol Channel. A bank of furnace slag, for directing the -course of the river, had been made previously by Mr. Palmer, and -continued as far seawards as it was then thought could be done with -safety. Mr. Brunel carried a training bank still farther, and succeeded -in cutting off a bend of the river; Mr. Brereton has since extended the -navigable channel in a straight line to low-water mark, a distance of -two miles; and the bar has been lowered to within 1 foot of the level of -the dock sill. - -[182] Reports on the Paris Universal Exhibition 1867 vol. i., p. xxiv. -194 - -[183] When, at the close of the Exhibition, Mr. Brunel was compelled, -much against his will, to accept a pecuniary acknowledgment of his -services, he spent the money in the erection of model cottages at -Barton, a village near his property in Devonshire. - -[184] See Report of the Select Committee of the House of Commons on -Ordnance, 1863, Minutes of Evidence and Appendix (ordered to be printed -July 23, 1863):--p. 306, Report of Ordnance Select Committee; p. 44, -Statement of Mr. Whitworth; p. 56, Evidence of Mr. Whitworth (Q. -1329-1337); pp. 58, 59, the same (Q. 1385-1410); pp. 402, 403, Papers -delivered in by Mr. Isambard Brunel; p. 110, Further Evidence of Mr. -Whitworth (Q. 2545-2551); p. 112, the same (Q. 2602-2610); p. 548, -Letter from Mr. Westley Richards to Mr. Isambard Brunel. - -[185] Captain Claxton, at Mr. Brunel's desire, went for a voyage in -Messrs. Ruthven's vessel, the 'Enterprise,' in order to test her -performances. - -[186] This appears to be the only instance in which Mr. Brunel printed -an account of any of his works. - -[187] On this application of tin for the covering of the roof, Dr. -Parkes observes (_Manual of Practical Hygiene_, London, 1869, p. -317):--'In the Crimean War the roofs of Renkioi Hospital, on the -Dardanelles, were covered with polished tin; it was found, however, -somewhat difficult to place it so as to exclude rain, and the surface -soon became tarnished. The thermometric experiments did not show a -greater lessening of heat than 3 deg. Fahr. below houses not tin-coated.' - -[188] 'At Renkioi, in Turkey, Mr. Brunel supplied square wooden sewers -about 15 inches to the side; they were tarred inside, and acted most -admirably without leakage for fifteen months, till the end of the war. -The water-closets (Jennings's simple syphon), arranged with a small -water-box below the cistern, to economise water, never got out of order, -and in fact the drainage of the hospital was literally perfect. I have -little doubt such well-tarred wooden sewers would last two or three -years' (Parkes's _Manual of Practical Hygiene_, p. 635). - -[189] The woodcut, fig. 22, is a reduction of part of this drawing. - -[190] The case of Ranger _v._ the Great Western Railway Company. - -[191] See above, p. 192. - -[192] The remainder of this letter is printed above, p. 192. - -[193] Although Mr. Brunel endeavoured, as far as possible, to lay aside -work during his visits to Watcombe, he found occasions for the use of -his mechanical knowledge. He prepared tools for transplanting young -trees; he did not, however, succeed in making them flourish as well as -before they were transplanted, though he attended to the work himself, -and took care that a large amount of earth was moved with the tree. The -bridge of rough poles across the turnpike road between Teignmouth and -Torquay is as good of its kind as his larger works. - -[194] On June 10, 1830, when he was twenty-four years old, Mr. Brunel -was elected a Fellow of the Royal Society. He subsequently became a -member of most of the other scientific societies; but he rarely attended -any meetings, except those of the Institution of Civil Engineers. - -[195] At the beginning of 1858, on the expiration of Mr. Robert -Stephenson's term of office as President of the Institution of Civil -Engineers, Mr. Brunel came next in rotation for election; but his -failing health, and the pressure of his professional duties, led him to -request that he might not then be put in nomination.--- See Inaugural -Address of John Fowler, Esq., January 9, 1866. - -[196] A drawing of their Nile boat, the 'Florence,' which he made for -his daughter, exhibits the same beautiful minuteness which appears in -all his early sketches for the Clifton bridge and Great Western Railway. - -[197] Mr. Brunel's Nile boat, being of iron, could not safely go up the -Cataracts. - -[198] A few weeks after Mr. Brunel's death, a meeting of his friends was -held, when it was determined to raise some memorial to him. A statue was -made by the late Baron Marochetti, and a site for it promised by the -First Commissioner of Works; but it has not yet been erected. - -Mr. Brunel's family, by the permission of the Dean of Westminster, have -placed a memorial window in the north aisle of the nave of Westminster -Abbey. - -Along the bottom of the window (which consists of two lights, each 23 -feet 6 inches high and 4 feet wide, surmounted by a quatrefoil opening, -6 feet 6 inches across) is the Inscription, 'IN MEMORY OF ISAMBARD -KINGDOM BRUNEL, CIVIL ENGINEER. BORN APRIL 9, 1806. DEPARTED THIS LIFE, -SEPTEMBER 15, 1859.' Over this are four allegorical figures (two in each -light): Fortitude, Justice, Faith, and Charity. The upper part of the -window consists of six panels, divided by a pattern work of lilies and -pomegranates. The panels contain subjects from the history of the -Temple. The three subjects in the western light represent scenes from -the Old Testament--viz. the Dedication of the Temple by Solomon, the -Finding of the Book of the Law by Hilkiah, and the Laying the -Foundations of the Second Temple. The subjects in the eastern light are -from the New Testament--viz. Simeon Blessing the Infant Saviour, Christ -Disputing with the Doctors, and The Disciples pointing out to Christ the -Buildings of the Temple. In the heads of each light are angels kneeling, -and in the quatrefoil is a representation of Our Lord in Glory, -surrounded by angels. - -The work was placed in the hands of Mr. R. Norman Shaw, architect, who -prepared the general design, arranged the scale of the various figures, -and designed the ornamental pattern work. The figure subjects were drawn -by Mr. Henry Holiday, and the whole design was executed in glass by -Messrs. Heaton, Butler, & Bayne. - -[199] Mr. Locke here spoke in feeling language of Mr. Robert Stephenson. - -[200] There appears, from the table, to be an immense extent of -paddle-board to this vessel, if the table be correct--greater than the -midship section. - -[201] In a Report by Mr. Brunel on improvements in the port of Bristol, -dated December 26, 1839, the following passage occurs: 'A great change -is unquestionably about to take place in the carriage of merchandise by -sea, a change similar, though possibly not so striking, as that which -has so suddenly been effected by railways in land carriage. To ensure -the speed which the passenger traffic demands, great size in the vessels -is required; in the course of a very few years we shall find Atlantic -steamers desirous of taking 500 or 600 tons of cargo to make up their -draught.' - - - - - - - - -End of the Project Gutenberg EBook of The life of Isambard Kingdom Brunel, -Civil Engineer, by Isambard Brunel - -*** END OF THIS PROJECT GUTENBERG EBOOK THE LIFE OF I K BRUNEL *** - -***** This file should be named 41210.txt or 41210.zip ***** -This and all associated files of various formats will be found in: - http://www.gutenberg.org/4/1/2/1/41210/ - -Produced by Chuck Greif and the Online Distributed -Proofreading Team at http://www.pgdp.net (This file was -produced from images available at The Internet Archive) - - -Updated editions will replace the previous one--the old editions -will be renamed. - -Creating the works from public domain print editions 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 with public domain eBooks. 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 -http://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 in the public domain 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 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/license - -1.E.2. If an individual Project Gutenberg-tm electronic work is derived -from the public domain (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 Michael -Hart, 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 -public domain works 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 web page at http://www.pglaf.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. Its 501(c)(3) letter is posted at -http://pglaf.org/fundraising. 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 located at 4557 Melan Dr. S. -Fairbanks, AK, 99712., 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 -business@pglaf.org. Email contact links and up to date contact -information can be found at the Foundation's web site and official -page at http://pglaf.org - -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 http://pglaf.org - -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: http://pglaf.org/donate - - -Section 5. General Information About Project Gutenberg-tm electronic -works. - -Professor Michael S. Hart is the originator of the Project Gutenberg-tm -concept of a library of electronic works that could be freely shared -with anyone. For thirty 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 Public Domain 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: - - http://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. |