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+Project Gutenberg's How it Flies or, Conquest of the Air, by Richard Ferris
+
+This eBook is for the use of anyone anywhere in the United States and most
+other parts of the world at no cost and with almost no restrictions
+whatsoever.  You may copy it, give it away or re-use it under the terms of
+the Project Gutenberg License included with this eBook or online at
+www.gutenberg.org.  If you are not located in the United States, you'll have
+to check the laws of the country where you are located before using this ebook.
+
+Title: How it Flies or, Conquest of the Air
+       The Story of Man's Endeavors to Fly and of the Inventions
+       by which He Has Succeeded
+
+Author: Richard Ferris
+
+Release Date: August 5, 2017 [EBook #55268]
+
+Language: English
+
+Character set encoding: UTF-8
+
+*** START OF THIS PROJECT GUTENBERG EBOOK HOW IT FLIES OR, CONQUEST OF AIR ***
+
+
+
+
+Produced by Chris Curnow, Wayne Hammond and the Online
+Distributed Proofreading Team at http://www.pgdp.net
+
+
+
+
+
+
+
+[Illustration: ORVILLE WRIGHT IN THE 80-MILE-AN-HOUR “BABY WRIGHT”
+RACER.]
+
+
+
+
+  How It Flies
+
+  or,
+
+  THE CONQUEST OF THE AIR
+
+  The Story of Man’s Endeavors to Fly and of the
+  Inventions by which He Has Succeeded
+
+  By
+
+  RICHARD FERRIS, B.S., C.E.
+
+  Illustrated by Over One Hundred and Fifty Half-tones and Line
+  Drawings, Showing the Stages of Development from the
+  Earliest Balloon to the Latest Monoplane and Biplane
+
+  New York
+
+  THOMAS NELSON AND SONS
+
+  381-385 Fourth Avenue
+
+
+Copyright, 1910, by
+
+THOMAS NELSON & SONS
+
+
+THE TROW PRESS, NEW YORK
+
+
+
+
+PREFACE
+
+
+In these pages, by means of simple language and suitable pictures, the
+author has told the story of the Ships of the Air. He has explained
+the laws of their flight; sketched their development to the present
+day; shown how to build the flying machine and the balloon, and how
+to operate them; recounted what man has done, and what he hopes to do
+with their aid. In a word, all the essential facts that enter into the
+Conquest of the Air have been gathered into orderly form, and are here
+presented to the public.
+
+We who live to-day have witnessed man’s great achievement; we have seen
+his dream of ages come true. Man has learned to _fly_!
+
+The air which surrounds us, so intangible and so commonplace that
+it seldom arrests our attention, is in reality a vast, unexplored
+ocean, fraught with future possibilities. Even now, the pioneers of
+a countless fleet are hovering above us in the sky, while steadily,
+surely these wonderful possibilities are unfolded.
+
+The Publishers take pleasure in acknowledging their indebtedness to the
+_Scientific American_ for their courtesy in permitting the use of many
+of the illustrations appearing in this book.
+
+NEW YORK, October 20, 1910.
+
+
+
+
+CONTENTS
+
+
+  CHAPTER                                       PAGE
+
+        PREFACE                                    7
+
+     I. INTRODUCTORY                              11
+
+    II. THE AIR                                   20
+
+   III. LAWS OF FLIGHT                            37
+
+    IV. FLYING MACHINES                           55
+
+     V. FLYING MACHINES: THE BIPLANE              78
+
+    VI. FLYING MACHINES: THE MONOPLANE           112
+
+   VII. FLYING MACHINES: OTHER FORMS             141
+
+  VIII. FLYING MACHINES: HOW TO OPERATE          151
+
+    IX. FLYING MACHINES: HOW TO BUILD            174
+
+     X. FLYING MACHINES: MOTORS                  193
+
+    XI. MODEL FLYING MACHINES                    215
+
+   XII. THE GLIDER                               241
+
+  XIII. BALLOONS                                 257
+
+    XIV. BALLOONS: THE DIRIGIBLE                 296
+
+     XV. BALLOONS: HOW TO OPERATE                340
+
+    XVI. BALLOONS: HOW TO MAKE                   351
+
+   XVII. MILITARY AERONAUTICS                    363
+
+  XVIII. BIOGRAPHIES OF PROMINENT AERONAUTS      379
+
+    XIX. CHRONICLE OF AVIATION ACHIEVEMENTS      407
+
+     XX. EXPLANATION OF AERONAUTICAL
+               TERMS                             452
+
+
+
+
+HOW IT FLIES
+
+
+
+
+Chapter I.
+
+INTRODUCTORY.
+
+    The sudden awakening--Early successes--Influence of the gasoline
+    engine on aeroplanes--On dirigible balloons--Interested
+    inquiry--Some general terms defined.
+
+
+In the year 1908 the world awakened suddenly to the realization that at
+last the centuries of man’s endeavor to fly mechanically had come to
+successful fruition.
+
+There had been a little warning. In the late autumn of 1906,
+Santos-Dumont made a flight of 720 feet in a power-driven machine.
+There was an exclamation of wonder, a burst of applause--then a relapse
+into unconcern.
+
+In August, 1907, Louis Bleriot sped free of the ground for 470 feet;
+and in November, Santos-Dumont made two flying leaps of barely 500
+feet. That was the year’s record, and it excited little comment. It is
+true that the Wright brothers had been making long flights, but they
+were in secret. There was no public knowledge of them.
+
+In 1908 came the revelation. In March, Delagrange flew in a Voisin
+biplane 453 feet, carrying Farman with him as a passenger. Two weeks
+later he flew alone nearly 2½ miles. In May he flew nearly 8 miles. In
+June his best flight was 10½ miles. Bleriot came on the scene again
+in July with a monoplane, in which he flew 3¾ miles. In September,
+Delagrange flew 15 miles--in less than 30 minutes. In the same month
+the Wrights began their wonderful public flights. Wilbur, in France,
+made records of 41, 46, 62, and 77 miles, while Orville flew from 40 to
+50 miles at Fort Myer, Va. Wilbur Wright’s longest flight kept him in
+the air 2 hours and 20 minutes.
+
+The goal had been reached--men had achieved the apparently impossible.
+The whole world was roused to enthusiasm.
+
+Since then, progress has been phenomenally rapid, urged on by the
+striving of the inventors, the competition of the aircraft builders,
+and the contests for records among the pilots.
+
+By far the largest factor in the triumph of the aeroplane is the
+improved gasoline engine, designed originally for automobiles. Without
+this wonderful type of motor, delivering a maximum of power with a
+minimum of weight, from concentrated fuel, the flying machine would
+still be resting on the earth.
+
+[Illustration: The Renard and Krebs airship _La France_, at
+Chalais-Meudon.]
+
+Nor has the influence of the gasoline motor been much less upon that
+other great class of aircraft, the dirigible balloon. After 1885, when
+Renard and Krebs’ airship _La France_ made its two historic voyages
+from Chalais-Meudon to Paris, returning safely to its shed, under the
+propulsion of an electric motor, the problem of the great airship lay
+dormant, waiting for the discovery of adequate motive power. If the
+development of the dirigible balloon seems less spectacular than that
+of the aeroplane, it is because the latter had to be created; the
+dirigible, already in existence, had only to be revivified.
+
+Confronted with these new and strange shapes in the sky, some making
+stately journeys of hundreds of miles, others whirring hither and
+thither with the speed of the whirlwind, wonder quickly gives way to
+the all-absorbing question: _How do they fly?_ To answer fully and
+satisfactorily, it seems wise, for many readers, to recall in the
+succeeding chapters some principles doubtless long since forgotten.
+
+       *       *       *       *       *
+
+As with every great advance in civilization, this expansion of the
+science of aeronautics has had its effect upon the language of the day.
+Terms formerly in use have become restricted in application, and other
+terms have been coined to convey ideas so entirely new as to find no
+suitable word existent in our language. It seems requisite, therefore,
+first to acquaint the reader with clear definitions of the more common
+terms that are used throughout this book.
+
+_Aeronautics_ is the word employed to designate the entire subject of
+aerial navigation. An _aeronaut_ is a person who sails, or commands,
+any form of aircraft, as distinguished from a passenger.
+
+_Aviation_ is limited to the subject of flying by machines which are
+not floated in the air by gas. An _aviator_ is an operator of such
+machine.
+
+[Illustration: A free balloon, with parachute.]
+
+Both aviators and aeronauts are often called _pilots_.
+
+A _balloon_ is essentially an envelope or bag filled with some gaseous
+substance which is lighter, bulk for bulk, than the air at the surface
+of the earth, and which serves to float the apparatus in the air. In
+its usual form it is spherical, with a car or basket suspended below
+it. It is a _captive balloon_ if it is attached to the ground by a
+cable, so that it may not rise above a certain level, nor float away in
+the wind. It is a _free balloon_ if not so attached or anchored, but is
+allowed to drift where the wind may carry it, rising and falling at the
+will of the pilot.
+
+[Illustration: A dirigible balloon.]
+
+A _dirigible balloon_, sometimes termed simply a dirigible, usually has
+its gas envelope elongated in form. It is fitted with motive power to
+propel it, and steering mechanism to guide it. It is distinctively the
+_airship_.
+
+_Aeroplanes_ are those forms of flying machines which depend for their
+support in the air upon the spread of surfaces which are variously
+called wings, sails, or planes. They are commonly driven by propellers
+actuated by motors. When not driven by power they are called _gliders_.
+
+[Illustration: A biplane glider.]
+
+Aeroplanes exist in several types: the _monoplane_, with one spread
+of surface; the _biplane_, with two spreads, one above the other; the
+_triplane_, with three spreads, or decks; the _multiplane_, with more
+than three.
+
+The _tetrahedral plane_ is a structure of many small cells set one upon
+another.
+
+_Ornithopter_ is the name given to a flying machine which is operated
+by flapping wings.
+
+[Illustration: A parachute descending.]
+
+_Helicopter_ is used to designate machines which are lifted vertically
+and sustained in the air by propellers revolving in a horizontal plane,
+as distinguished from the propellers of the aeroplane, which revolve in
+vertical planes.
+
+A _parachute_ is an umbrella-like contrivance by which an aeronaut may
+descend gently from a balloon in mid-air, buoyed up by the compression
+of the air under the umbrella.
+
+For the definition of other and more technical terms the reader is
+referred to the carefully prepared Glossary toward the end of the book.
+
+
+
+
+Chapter II.
+
+THE AIR.
+
+    Intangibility of air--Its
+    substance--Weight--Extent--Density--Expansion
+    by heat--Alcohol fire--Turbulence of the
+    air--Inertia--Elasticity--Viscosity--Velocity of
+    winds--Aircurrents--Cloud levels--Aerological stations--High
+    altitudes--Practical suggestions--The ideal highway.
+
+
+The air about us seems the nearest approach to nothingness that we know
+of. A pail is commonly said to be empty--to have nothing in it--when it
+is filled only with air. This is because our senses do not give us any
+information about air. We cannot see it, hear it, touch it.
+
+When air is in motion (wind) we hear the noises it makes as it passes
+among other objects more substantial; and we feel it as it blows by us,
+or when we move rapidly through it.
+
+We get some idea that it exists as a substance when we see dead leaves
+caught up in it and whirled about; and, more impressively, when in the
+violence of the hurricane it seizes upon a body of great size and
+weight, like the roof of a house, and whisks it away as though it were
+a feather, at a speed exceeding that of the fastest railroad train.
+
+In a milder form, this invisible and intangible air does some of our
+work for us in at least two ways that are conspicuous: it moves ships
+upon the ocean, and it turns a multitude of windmills, supplying the
+cheapest power known.
+
+That this atmosphere is really a fluid ocean, having a definite
+substance, and in some respects resembling the liquid ocean upon which
+our ships sail, and that we are only crawling around on the bottom
+of it, as it were, is a conception we do not readily grasp. Yet this
+conception must be the foundation of every effort to sail, to fly, in
+this aerial ocean, if such efforts are to be crowned with success.
+
+As a material substance the air has certain physical properties, and
+it is the part of wisdom for the man who would fly to acquaint himself
+with these properties. If they are helpful to his flight, he wants to
+use them; if they hinder, he must contrive to overcome them.
+
+In general, it may be said that the air, being in a gaseous form,
+partakes of the properties of all gases--and these may be studied
+in any text-book on physics, Here we are concerned only with those
+qualities which affect conditions under which we strive to fly.
+
+Of first importance is the fact that air has _weight_. That is, in
+common with all other substances, it is attracted by the mass of the
+earth exerted through the force we call gravity. At the level of the
+sea, this attraction causes the air to press upon the earth with a
+weight of nearly fifteen pounds (accurately, 14.7 lbs.) to the square
+inch, when the temperature is at 32° F. That pressure is the weight of
+a column of air one inch square at the base, extending upward to the
+outer limit of the atmosphere--estimated to be about 38 miles (some say
+100 miles) above sea-level. The practical fact is that normal human
+life cannot exist above the level of 15,000 feet, or a little less than
+three miles; and navigation of the air will doubtless be carried on at
+a much lower altitude, for reasons which will appear as we continue.
+
+The actual weight of a definite quantity of dry air--for instance,
+a cubic foot--is found by weighing a vessel first when full of air,
+and again after the air has been exhausted from it with an air-pump.
+In this way it has been determined that a cubic foot of dry air,
+at the level of the sea, and at a temperature of 32° F., weighs 565
+grains--about 0.0807 lb. At a height above the level of the sea, a
+cubic foot of air will weigh less than the figure quoted, for its
+density decreases as we go upward, the pressure being less owing to
+the diminished attraction of the earth at the greater distance. For
+instance, at the height of a mile above sea-level a cubic foot of air
+will weigh about 433 grains, or 0.0619 lb. At the height of five miles
+it will weigh about 216 grains, or 0.0309 lb. At thirty-eight miles
+it will have no weight at all, its density being so rare as just to
+balance the earth’s attraction. It has been calculated that the whole
+body of air above the earth, if it were all of the uniform density of
+that at sea-level, would extend only to the height of 26,166 feet.
+Perhaps a clearer comprehension of the weight and pressure of the ocean
+of air upon the earth may be gained by recalling that the pressure of
+the 38 miles of atmosphere is just equal to balancing a column of water
+33 feet high. The pressure of the air, therefore, is equivalent to the
+pressure of a flood of water 33 feet deep.
+
+[Illustration: Comparative Elevations of Earth and Air.]
+
+But air is seldom dry. It is almost always mingled with the vapor
+of water, and this vapor weighs only 352 grains per cubic foot at
+sea-level. Consequently the mixture--damp air--is lighter than dry air,
+in proportion to the moisture it contains.
+
+[Illustration: Apparatus to show effects of heat on air currents. _a_,
+alcohol lamp; _b_, ice. The arrows show direction of currents.]
+
+Another fact very important to the aeronaut is that the air is in
+_constant motion_. Owing to its ready expansion by heat, a body of
+air occupying one cubic foot when at a temperature of 32° F. will
+occupy more space at a higher temperature, and less space at a lower
+temperature. Hence, heated air will flow upward until it reaches a
+point where the natural density of the atmosphere is the same as its
+expanded density due to the heating. Here another complication comes
+into play, for ascending air is cooled at the rate of one degree for
+every 183 feet it rises; and as it cools it grows denser, and the speed
+of its ascension is thus gradually checked. After passing an altitude
+of 1,000 feet the decrease in temperature is one degree for each 320
+feet of ascent. In general, it may be stated that air is expanded
+one-tenth of its volume for each 50° F. that its temperature is raised.
+
+This highly unstable condition under ordinary changes of temperature
+causes continual movements in the air, as different portions of it are
+constantly seeking that position in the atmosphere where their density
+at that moment balances the earth’s attraction.
+
+Sir Hiram Maxim relates an incident which aptly illustrates the effect
+of change of temperature upon the air. He says: “On one occasion,
+many years ago, I was present when a bonded warehouse in New York
+containing 10,000 barrels of alcohol was burned.... I walked completely
+around the fire, and found things just as I expected. The wind was
+blowing a perfect hurricane through every street in the direction of
+the fire, although it was a dead calm everywhere else; the flames
+mounted straight in the air to an enormous height, and took with them a
+large amount of burning wood. When I was fully 500 feet from the fire,
+a piece of partly burned one-inch board, about 8 inches wide and 4 feet
+long, fell through the air and landed near me. This board had evidently
+been taken up to a great height by the tremendous uprush of air caused
+by the burning alcohol.”
+
+That which happened on a small scale, with a violent change of
+temperature, in the case of the alcohol fire, is taking place on a
+larger scale, with milder changes in temperature, all over the world.
+The heating by the sun in one locality causes an expansion of air
+at that place, and cooler, denser air rushes in to fill the partial
+vacuum. In this way winds are produced.
+
+So the air in which we are to fly is in a state of constant motion,
+which may be likened to the rush and swirl of water in the rapids of a
+mountain torrent. The tremendous difference is that the perils of the
+water are in plain sight of the navigator, and may be guarded against,
+while those of the air are wholly invisible, and must be met as they
+occur, without a moment’s warning.
+
+[Illustration:
+
+    The solid arrows show the directions of a cyclonic wind on
+    the earth’s surface. At the centre the currents go directly
+    upward. In the upper air above the cyclone the currents have the
+    directions of the dotted arrows.]
+
+Next in importance, to the aerial navigator, is the air’s _resistance_.
+This is due in part to its density at the elevation at which he is
+flying, and in part to the direction and intensity of its motion, or
+the wind. While this resistance is far less than that of water to the
+passage of a ship, it is of serious moment to the aeronaut, who must
+force his fragile machine through it at great speed, and be on the
+alert every instant to combat the possibility of a fall as he passes
+into a rarer and less buoyant stratum.
+
+[Illustration:
+
+    Diagram showing disturbance of wind currents by inequalities of
+    the ground, and the smoother currents of the upper air. Note the
+    increase of density at A and B, caused by compression against the
+    upper strata.]
+
+Three properties of the air enter into the sum total of its
+resistance--inertia, elasticity, and viscosity. Inertia is its tendency
+to remain in the condition in which it may be: at rest, if it is still;
+in motion, if it is moving. Some force must be applied to disturb this
+inertia, and in consequence when the inertia is overcome a certain
+amount of force is used up in the operation. Elasticity is that
+property by virtue of which air tends to reoccupy its normal amount
+of space after disturbance. An illustration of this tendency is the
+springing back of the handle of a bicycle pump if the valve at the
+bottom is not open, and the air in the pump is simply compressed, not
+forced into the tire. Viscosity may be described as “stickiness”--the
+tendency of the particles of air to cling together, to resist
+separation. To illustrate: molasses, particularly in cold weather,
+has greater viscosity than water; varnish has greater viscosity than
+turpentine. Air exhibits some viscosity, though vastly less than that
+of cold molasses. However, though relatively slight, this viscosity has
+a part in the resistance which opposes the rapid flight of the airship
+and aeroplane; and the higher the speed, the greater the retarding
+effect of viscosity.
+
+The inertia of the air, while in some degree it blocks the progress
+of his machine, is a benefit to the aeronaut, for it is inertia which
+gives the blades of his propeller “hold” upon the air. The elasticity
+of the air, compressed under the curved surfaces of the aeroplane, is
+believed to be helpful in maintaining the lift. The effect of viscosity
+may be greatly reduced by using surfaces finished with polished
+varnish--just as greasing a knife will permit it to be passed with
+less friction through thick molasses.
+
+In the case of winds, the inertia of the moving mass becomes what is
+commonly termed “wind pressure” against any object not moving with it
+at an equal speed. The following table gives the measurements of wind
+pressure, as recorded at the station on the Eiffel Tower, for differing
+velocities of wind:
+
+  +----------+------------+---------------+
+  | Velocity |  Velocity  |   Pressure    |
+  | in Miles |  in Feet   | in Pounds on  |
+  | per Hour | per Second | a Square Foot |
+  +----------+------------+---------------+
+  |    2     |     2.9    |      0.012    |
+  |    4     |     5.9    |      0.048    |
+  |    6     |     8.8    |      0.108    |
+  |    8     |    11.7    |      0.192    |
+  |   10     |    14.7    |      0.300    |
+  |   15     |    22.0    |      0.675    |
+  |   20     |    29.4    |      1.200    |
+  |   25     |    36.7    |      1.875    |
+  |   30     |    44.0    |      2.700    |
+  |   35     |    51.3    |      3.675    |
+  |   40     |    58.7    |      4.800    |
+  |   45     |    66.0    |      6.075    |
+  |   50     |    73.4    |      7.500    |
+  |   60     |    88.0    |     10.800    |
+  |   70     |   102.7    |     14.700    |
+  |   80     |   117.2    |     19.200    |
+  |   90     |   132.0    |     24.300    |
+  |  100     |   146.7    |     30.000    |
+  +----------+------------+---------------+
+
+In applying this table, the velocity to be considered is the net
+velocity of the movements of the airship and of the wind. If the ship
+is moving 20 miles an hour _against_ a head wind blowing 20 miles an
+hour, the net velocity of the wind will be 40 miles an hour, and the
+pressure 4.8 lbs. a square foot of surface presented. Therefore the
+airship will be standing still, so far as objects on the ground are
+concerned. If the ship is sailing 20 miles an hour _with_ the wind,
+which is blowing 20 miles an hour, the pressure per square foot will be
+only 1.2 lbs.; while as regards objects on the ground, the ship will be
+travelling 40 miles an hour.
+
+[Illustration:
+
+    Apparatus for the study of the action of air in motion; a blower
+    at the farther end of the great tube sends a “wind” of any
+    desired velocity through it. Planes and propellers of various
+    forms are thus tested.]
+
+Systematic study of the movements of the air currents has not been
+widespread, and has not progressed much beyond the gathering of
+statistics which may serve as useful data in testing existing theories
+or formulating new ones.
+
+It is already recognized that there are certain “tides” in the
+atmosphere, recurring twice daily in six-hour periods, as in the case
+of the ocean tides, and perhaps from the same causes. Other currents
+are produced by the earth’s rotation. Then there are the five-day
+oscillations noted by Eliot in India, and daily movements, more or less
+regular, due to the sun’s heat by day and the lack of it by night.
+The complexity of these motions makes scientific research extremely
+difficult.
+
+Something definite has been accomplished in the determination of wind
+velocities, though this varies largely with the locality. In the United
+States the average speed of the winds is 9½ miles per hour; in Europe,
+10⅓ miles; in Southern Asia, 6½ miles; in the West Indies, 6⅕ miles; in
+England, 12 miles; over the North Atlantic Ocean, 29 miles per hour.
+Each of these average velocities varies with the time of year and time
+of day, and with the distance from the sea. The wind moves faster over
+water and flat, bare land than over hilly or forest-covered areas.
+Velocities increase as we go upward in the air, being at 1,600 feet
+twice what they are at 100 feet. Observations of the movements of cloud
+forms at the Blue Hill Observatory, near Boston, give the following
+results:
+
+  +---------------+---------+---------------+
+  |  Cloud Form   | Height  | Average Speed |
+  |               | in Feet |   per Hour    |
+  +---------------+---------+---------------+
+  | Stratus       |   1,676 |     19 miles. |
+  | Cumulus       |   5,326 |     24 miles. |
+  | Alto-cumulus  |  12,724 |     34 miles. |
+  | Cirro-cumulus |  21,888 |     71 miles. |
+  | Cirrus        |  29,317 |     78 miles. |
+  +---------------+---------+---------------+
+
+In winter the speed of cirrus clouds may reach 96 miles per hour.
+
+There are forty-nine stations scattered over Germany where statistics
+concerning winds are gathered expressly for the use of aeronauts. At
+many of these stations records have been kept for twenty years. Dr.
+Richard Assman, director of the aerological observatory at Lindenburg,
+has prepared a comprehensive treatise of the statistics in possession
+of these stations, under the title of _Die Winde in Deutschland_. It
+shows for each station, and for each season of the year, how often the
+wind blows from each point of the compass; the average frequency of
+the several degrees of wind; when and where aerial voyages may safely
+be made; the probable drift of dirigibles, etc. It is interesting to
+note that Friedrichshafen, where Count Zeppelin’s great airship sheds
+are located, is not a favorable place for such vessels, having a yearly
+record of twenty-four stormy days, as compared with but two stormy days
+at Celle, four at Berlin, four at Cassel, and low records at several
+other points.
+
+In practical aviation, a controlling factor is the density of the air.
+We have seen that at an altitude of five miles the density is about
+three-eighths the density at sea-level. This means that the supporting
+power of the air at a five-mile elevation is so small that the area of
+the planes must be increased to more than 2½ times the area suited to
+flying near the ground, or that the speed must be largely increased.
+Therefore the adjustments necessary for rising at the lower level and
+journeying in the higher level are too large and complex to make flying
+at high altitudes practicable--leaving out of consideration the bitter
+cold of the upper regions.
+
+Mr. A. Lawrence Rotch, director of the Blue Hill Observatory, in his
+valuable book, _The Conquest of the Air_, gives this practical summary
+of a long series of studious observations: “At night, however, because
+there are no ascending currents, the wind is much steadier than in the
+daytime, making night the most favorable time for aerial navigation
+of all kinds.... A suitable height in the daytime, unless a strong
+westerly wind is sought, lies above the cumulus clouds, at the height
+of about a mile; but at night it is not necessary to rise so high; and
+in summer a region of relatively little wind is found at a height of
+about three-fourths of a mile, where it is also warmer and drier than
+in the daytime or at the ground.”
+
+Notwithstanding all difficulties, the fact remains that, once they are
+overcome, the air is the ideal highway for travel and transportation.
+On the sea, a ship may sail to right or left on one plane only. In
+the air, we may steer not only to right or left, but above and below,
+and obliquely in innumerable planes. We shall not need to traverse
+long distances in a wrong direction to find a bridge by which we may
+cross a river, nor zigzag for toilsome miles up the steep slopes of a
+mountain-side to the pass where we may cross the divide. The course of
+the airship is the proverbial bee-line--the most economical in time as
+well as in distance.
+
+
+
+
+Chapter III.
+
+LAWS OF FLIGHT.
+
+    The bird--Nature’s models--Man’s methods--Gravity--The
+    balloon--The airship--Resistance of the air--Winds--The
+    kite--Laws of motion and force--Application to
+    kite-flying--Aeroplanes.
+
+
+If we were asked to explain the word “flying” to some foreigner who did
+not know what it meant, we should probably give as an illustration the
+bird. This would be because the bird is so closely associated in our
+thoughts with flying that we can hardly think of the one without the
+other.
+
+It is natural, therefore, that since men first had the desire to fly
+they should study the form and motions of the birds in the air, and
+try to copy them. Our ancestors built immense flopping wings, into
+the frames of which they fastened themselves, and with great muscular
+exertion of arms and legs strove to attain the results that the bird
+gets by apparently similar motions.
+
+However, this mental coupling of the bird with the laws of flight has
+been unfortunate for the achievement of flight by man. And this is
+true even to the present day, with its hundreds of successful flying
+machines that are not in the least like a bird. This wrongly coupled
+idea is so strong that scientific publications print pages of research
+by eminent contributors into the flight of birds, with the attempt
+to deduce lessons therefrom for the instruction of the builders and
+navigators of flying machines.
+
+These arguments are based on the belief that Nature never makes a
+mistake; that she made the bird to fly, and therefore the bird must be
+the most perfect model for the successful flying machine. But the truth
+is, the bird was not made primarily to fly, any more than man was made
+to walk. Flying is an incident in the life of a bird, just as walking
+is an incident in the life of a man. Flying is simply a bird’s way of
+getting about from place to place, on business or on pleasure, as the
+case may be.
+
+Santos-Dumont, in his fascinating book, _My Air-Ships_, points out
+the folly of blindly following Nature by showing that logically such
+a procedure would compel us to build our locomotives on the plan of
+gigantic horses, with huge iron legs which would go galloping about
+the country in a ridiculously terrible fashion; and to construct our
+steamships on the plan of giant whales, with monstrous flapping fins
+and wildly lashing tails.
+
+Sir Hiram Maxim says something akin to this in his work, _Artificial
+and Natural Flight_: “It appears to me that there is nothing in Nature
+which is more efficient, or gets a better grip on the water, than a
+well-made screw propeller; and no doubt there would have been fish with
+screw propellers, providing Dame Nature could have made an animal in
+two pieces. It is very evident that no living creature could be made in
+two pieces, and two pieces are necessary if one part is stationary and
+the other revolves; however, the tails and fins very often approximate
+to the action of propeller blades; they turn first to the right and
+then to the left, producing a sculling effect which is practically the
+same. This argument might also be used against locomotives. In all
+Nature we do not find an animal travelling on wheels, but it is quite
+possible that a locomotive might be made that would walk on legs at
+the rate of two or three miles an hour. But locomotives with wheels
+are able to travel at least three times as fast as the fleetest animal
+with legs, and to continue doing so for many hours at a time, even when
+attached to a very heavy load. In order to build a flying machine with
+flapping wings, to exactly imitate birds, a very complicated system of
+levers, cams, cranks, etc., would have to be employed, and these of
+themselves would weigh more than the wings would be able to lift.”
+
+As with the man-contrived locomotive, so the perfected airship will be
+evolved from man’s understanding of the obstacles to his navigation
+of the air, and his overcoming of them by his inventive genius. This
+will not be in Nature’s way, but in man’s own way, and with cleverly
+designed machinery such as he has used to accomplish other seeming
+impossibilities. With the clearing up of wrong conceptions, the path
+will be open to more rapid and more enduring progress.
+
+When we consider the problem of flying, the first obstacle we encounter
+is the attraction which the earth has for us and for all other objects
+on its surface. This we call weight, and we are accustomed to measure
+it in pounds.
+
+Let us take, for example, a man whose body is attracted by the earth
+with a force, or weight, of 150 pounds. To enable him to rise into the
+air, means must be contrived not only to counteract his weight, but to
+lift him--a force a little greater than 150 pounds must be exerted. We
+may attach to him a bag filled with some gas (as hydrogen) for which
+the earth has less attraction than it has for air, and which the air
+will push out of the way and upward until a place above the earth is
+reached where the attraction of air and gas is equal. A bag of this
+gas large enough to be pushed upward with a force equal to the weight
+of the man, plus the weight of the bag, and a little more for lifting
+power, will carry the man up. This is the principle of the ordinary
+balloon.
+
+Rising in the air is not flying. It is a necessary step, but real
+flying is to travel from place to place through the air. To accomplish
+this, some mechanism, or machinery, is needed to propel the man after
+he has been lifted into the air. Such machinery will have weight,
+and the bag of gas must be enlarged to counterbalance it. When this
+is done, the man and the bag of gas may move through the air, and
+with suitable rudders he may direct his course. This combination of
+the lifting bag of gas and the propelling machinery constitutes the
+dirigible balloon, or airship.
+
+[Illustration: Degen’s apparatus to lift the man and his flying
+mechanism with the aid of a gas-balloon. See Chapter IV.]
+
+The airship is affected equally with the balloon by prevailing winds.
+A breeze blowing 10 miles an hour will carry a balloon at nearly that
+speed in the direction in which it is blowing. Suppose the aeronaut
+wishes to sail in the opposite direction? If the machinery will propel
+his airship only 10 miles an hour in a calm, it will virtually stand
+still in the 10-mile breeze. If the machinery will propel his airship
+20 miles an hour in a calm, the ship will travel 10 miles an hour--as
+related to places on the earth’s surface--against the wind. But so far
+as the air is concerned, his speed through it is 20 miles an hour,
+and each increase of speed meets increased resistance from the air,
+and requires a greater expenditure of power to overcome. To reduce
+this resistance to the least possible amount, the globular form of the
+early balloon has been variously modified. Most modern airships have a
+“cigar-shaped” gas bag, so called because the ends look like the tip
+of a cigar. As far as is known, this is the balloon that offers less
+resistance to the air than any other.
+
+Another mechanical means of getting up into the air was suggested
+by the flying of kites, a pastime dating back at least 2,000 years,
+perhaps longer. Ordinarily, a kite will not fly in a calm, but with
+even a little breeze it will mount into the air by the upward thrust
+of the rushing breeze against its inclined surface, being prevented
+from blowing away (drifting) by the pull of the kite-string. The same
+effect will be produced in a dead calm if the operator, holding
+the string, runs at a speed equal to that of the breeze--with this
+important difference: not only will the kite rise in the air, but it
+will travel in the direction in which the operator is running, a part
+of the energy of the runner’s pull upon the string producing a forward
+motion, provided he holds the string taut. If we suppose the pull on
+the string to be replaced by an engine and revolving propeller in the
+kite, exerting the same force, we have exactly the principle of the
+aeroplane.
+
+As it is of the greatest importance to possess a clear understanding of
+the natural processes we propose to use, let us refer to any text-book
+on physics, and review briefly some of the natural laws relating to
+motion and force which apply to the problem of flight:
+
+    (_a_) Force is that power which changes or tends to change the
+    position of a body, whether it is in motion or at rest.
+
+    (_b_) A given force will produce the same effect, whether the
+    body on which it acts is acted upon by that force alone, or by
+    other forces at the same time.
+
+    (_c_) A force may be represented graphically by a straight
+    line--the point at which the force is applied being the beginning
+    of the line; the direction of the force being expressed by the
+    direction of the line; and the magnitude of the force being
+    expressed by the length of the line.
+
+    (_d_) Two or more forces acting upon a body are called component
+    forces, and the single force which would produce the same effect
+    is called the resultant.
+
+    (_e_) When two component forces act in different directions
+    the resultant may be found by applying the principle of the
+    parallelogram of forces--the lines (_c_) representing the
+    components being made adjacent sides of a parallelogram, and the
+    diagonal drawn from the included angle representing the resultant
+    in direction and magnitude.
+
+    (_f_) Conversely, a resultant motion may be resolved into its
+    components by constructing a parallelogram upon it as the
+    diagonal, either one of the components being known.
+
+[Illustration: The Deutsch de la Muerthe dirigible balloon
+_Ville-de-Paris_; an example of the “cigar-shaped” gas envelope.]
+
+Taking up again the illustration of the kite flying in a calm, let us
+construct a few diagrams to show graphically the forces at work upon
+the kite. Let the heavy line AB represent the centre line of the kite
+from top to bottom, and C the point where the string is attached, at
+which point we may suppose all the forces concentrate their action
+upon the plane of the kite. Obviously, as the flyer of the kite is
+running in a horizontal direction, the line indicating the pull of
+the string is to be drawn horizontal. Let it be expressed by CD. The
+action of the air pressure being at right angles to the plane of the
+kite, we draw the line CE representing that force. But as this is a
+_pressing_ force at the point C, we may express it as a _pulling_ force
+on the other side of the kite by the line CF, equal to CE and in the
+opposite direction. Another force acting on the kite is its weight--the
+attraction of gravity acting directly downward, shown by CG. We have
+given, therefore, the three forces, CD, CF, and CG. We now wish to find
+the value of the pull on the kite-string, CD, in two other forces, one
+of which shall be a lifting force, acting directly upward, and the
+other a propelling force, acting in the direction in which we desire
+the kite to travel--supposing it to represent an aeroplane for the
+moment.
+
+We first construct a parallelogram on CF and CG, and draw the diagonal
+CH, which represents the resultant of those two forces. We have then
+the two forces CD and CH acting on the point C. To avoid obscuring the
+diagram with too many lines, we draw a second figure, showing just
+these two forces acting on the point C. Upon these we construct a new
+parallelogram, and draw the diagonal CI, expressing their resultant.
+Again drawing a new diagram, showing this single force CI acting upon
+the point C, we resolve that force into two components--one, CJ,
+vertically upward, representing the lift; the other, CK, horizontal,
+representing the travelling power. If the lines expressing these forces
+in the diagrams had been accurately drawn to scale, the measurement of
+the two components last found would give definite results in pounds;
+but the weight of a kite is too small to be thus diagrammed, and only
+the principle was to be illustrated, to be used later in the discussion
+of the aeroplane.
+
+[Illustration]
+
+Nor is the problem as simple as the illustration of the kite suggests,
+for the air is compressible, and is moreover set in motion in the form
+of a current by a body passing through it at anything like the ordinary
+speed of an aeroplane. This has caused the curving of the planes (from
+front to rear) of the flying machine, in contrast with the flat plane
+of the kite. The reasoning is along this line: Suppose the main plane
+of an aeroplane six feet in depth (from front to rear) to be passing
+rapidly through the air, inclined upward at a slight angle. By the
+time two feet of this depth has passed a certain point, the air at
+that point will have received a downward impulse or compression which
+will tend to make it flow in the direction of the angle of the plane.
+The second and third divisions in the depth, each of two feet, will
+therefore be moving with a partial vacuum beneath, the air having been
+drawn away by the first segment. At the same time, the pressure of the
+air from above remains the same, and the result is that only the front
+edge of the plane is supported, while two-thirds of its depth is pushed
+down. This condition not only reduces the supporting surface to that of
+a plane two feet in depth, but, what is much worse, releases a tipping
+force which tends to throw the plane over backward.
+
+In order that the second section of the plane may bear upon the air
+beneath it with a pressure equal to that of the first, it must be
+inclined downward at double the angle (with the horizon) of the first
+section; this will in turn give to the air beneath it a new direction.
+The third section of the plane must then be set at a still deeper
+angle to give it support. Connecting these several directions with a
+smoothly flowing line without angles, we get the curved line of section
+to which the main planes of aeroplanes are bent.
+
+With these principles in mind, it is in order to apply them to the
+understanding of how an aeroplane flies. Wilbur Wright, when asked
+what kept his machine up in the air--why it did not fall to the
+ground--replied: “It stays up because it doesn’t have time to fall.”
+Just what he meant by this may be illustrated by referring to the
+common sport of “skipping stones” upon the surface of still water. A
+flat stone is selected, and it is thrown at a high speed so that the
+flat surface touches the water. It continues “skipping,” again and
+again, until its speed is so reduced that the water where it touches
+last has time to get out of the way, and the weight of the stone
+carries it to the bottom. On the same principle, a person skating
+swiftly across very thin ice will pass safely over if he goes so fast
+that the ice hasn’t time to break and give way beneath his weight. This
+explains why an aeroplane must move swiftly to stay up in the air,
+which has much less density than either water or ice. The minimum
+speed at which an aeroplane can remain in the air depends largely upon
+its weight. The heavier it is, the faster it must go--just as a large
+man must move faster over thin ice than a small boy. At some aviation
+contests, prizes have been awarded for the slowest speed made by an
+aeroplane. So far, the slowest on record is that of 21.29 miles an
+hour, made by Captain Dickson at the Lanark meet, Scotland, in August,
+1910. As the usual rate of speed is about 46 miles an hour, that is
+slow for an aeroplane; and as Dickson’s machine is much heavier than
+some others--the Curtiss machine, for instance--it is remarkably slow
+for that type of aeroplane.
+
+Just what is to be gained by offering a prize for slowest speed is
+difficult to conjecture. It is like offering a prize to a crowd of boys
+for the one who can skate slowest over thin ice. The minimum speed is
+the most dangerous with the aeroplane as with the skater. Other things
+being equal, the highest speed is the safest for an aeroplane. Even
+when his engine stops in mid-air, the aviator is compelled to keep up
+speed sufficient to prevent a fall by gliding swiftly downward until
+the very moment of landing.
+
+The air surface necessary to float a plane is spread out in one area in
+the monoplane, and divided into two areas, one above the other and 6
+to 9 feet apart, in the biplane; if closer than this, the disturbance
+of the air by the passage of one plane affects the supporting power
+of the other. It has been suggested that better results in the line
+of carrying power would be secured by so placing the upper plane that
+its front edge is a little back of the rear edge of the lower plane,
+in order that it may enter air that is wholly free from any currents
+produced by the rushing of the lower plane.
+
+As yet, there is a difference of opinion among the principal aeroplane
+builders as to where the propeller should be placed. All of the
+monoplanes have it in front of the main plane. Most of the biplanes
+have it behind the main plane; some have it between the two planes. If
+it is in front, it works in undisturbed air, but throws its wake upon
+the plane. If it is in the rear, the air is full of currents caused
+by the passage of the planes, but the planes have smooth air to glide
+into. As both types of machine are eminently successful, the question
+may not be so important as it seems to the disputants.
+
+The exact form of curve for the planes has not been decided upon.
+Experience has proven that of two aeroplanes having the same surface
+and run at the same speed, one may be able to lift twice as much as
+the other because of the better curvature of its planes. The action of
+the air when surfaces are driven through it is not fully understood.
+Indeed, the form of plane shown in the accompanying figure is called
+the aeroplane paradox. If driven in either direction it leaves the air
+with a _downward_ trend, and therefore exerts a proportional lifting
+power. If half of the plane is taken away, the other half is pressed
+downward. All of the lifting effect is in the curving of the top side.
+It seems desirable, therefore, that such essential factors should be
+thoroughly worked out, understood, and applied.
+
+[Illustration: Section of the “paradox” aeroplane.]
+
+
+
+
+Chapter IV.
+
+FLYING MACHINES.
+
+    Mythological--Leonardo da Vinci--Veranzio--John
+    Wilkins--Besnier--Marquis de
+    Bacqueville--Paucton--Desforges--Meerwein--Stentzel--Henson--Von
+    Drieberg--Wenham--Horatio Phillips--Sir Hiram
+    Maxim--Lilienthal--Langley--Ader--Pilcher--Octave
+    Chanute--Herring--Hargrave--The Wright
+    brothers--Archdeacon--Santos-Dumont--Voisin--Bleriot.
+
+
+The term Flying Machines is applied to all forms of aircraft which are
+heavier than air, and which lift and sustain themselves in the air by
+mechanical means. In this respect they are distinguished from balloons,
+which are lifted and sustained in the air by the lighter-than-air gas
+which they contain.
+
+From the earliest times the desire to fly in the air has been one of
+the strong ambitions of the human race. Even the prehistoric mythology
+of the ancient Greeks reflected the idea in the story of Icarus, who
+flew so near to the sun that the heat melted the wax which fastened his
+wings to his body, and he fell into the sea.
+
+Perhaps the first historical record in the line of mechanical flight
+worthy of attention exists in the remarkable sketches and plans for a
+flying mechanism left by Leonardo da Vinci at his death in 1519. He had
+followed the model of the flying bird as closely as possible, although
+when the wings were outspread they had an outline more like those of
+the bat. While extremely ingenious in the arrangement of the levers,
+the power necessary to move them fast enough to lift the weight of a
+man was far beyond the muscular strength of any human being.
+
+It was a century later, in 1617, that Veranzio, a Venetian, proved his
+faith in his inventive ability by leaping from a tower in Venice with
+a crude, parachute-like contrivance. He alighted without injury.
+
+In 1684, an Englishman, John Wilkins, then bishop of Chester, built
+a machine for flying in which he installed a steam-engine. No record
+exists of its performance.
+
+In 1678, a French locksmith by the name of Besnier devised what
+seems now a very crude apparatus for making descending flights, or
+glides, from elevated points. It was, however, at that date considered
+important enough to be described in the _Journal of the Savants_. It
+was a wholly unscientific combination of the “dog-paddle” motion in
+swimming, with wing areas which collapsed on the upward motion and
+spread out on the downward thrust. If it was ever put to a test it must
+have failed completely.
+
+In 1742, the Marquis de Bacqueville constructed an apparatus which
+some consider to have been based on Besnier’s idea--which seems rather
+doubtful. He fastened the surfaces of his aeroplane directly to his
+arms and legs, and succeeded in making a long glide from the window
+of his mansion across the garden of the Tuileries, alighting upon a
+washerwoman’s bench in the Seine without injury.
+
+Paucton, the mathematician, is credited with the suggestion of a flying
+machine with two screw propellers, which he called “pterophores”--a
+horizontal one to raise the machine into the air, and an upright one
+to propel it. These were to be driven by hand. With such hopelessly
+inadequate power it is not surprising that nothing came of it, yet
+the plan was a foreshadowing of the machine which has in these days
+achieved success.
+
+The Abbé Desforges gained a place in the annals of aeronautics by
+inventing a flying machine of which only the name “Orthoptere” remains.
+
+[Illustration: Meerwein’s Flying Machine. _A_, shows the position of
+the man in the wings, their comparative size, and the operating levers;
+_B_, position when in flight.]
+
+About 1780, Karl Friedrich Meerwein, an architect, and the Inspector of
+Public Buildings for Baden, Germany, made many scientific calculations
+and experiments on the size of wing surface needed to support a man
+in the air. He used the wild duck as a standard, and figured that a
+surface of 126 square feet would sustain a man in the air. This agrees
+with the later calculations of such experimenters as Lilienthal and
+Langley. Other of Meerwein’s conclusions are decidedly ludicrous. He
+held that the build of a man favors a horizontal position in flying, as
+his nostrils open in a direction which would be away from the wind, and
+so respiration would not be interfered with! Some of his reasoning is
+unaccountably astray; as, for instance, his argument that because the
+man hangs in the wings the weight of the latter need not be considered.
+It is almost needless to say that his practical trials were a total
+failure.
+
+[Illustration: Plan of Degen’s apparatus.]
+
+The next prominent step forward toward mechanical flight was made by
+the Australian watchmaker Degen, who balanced his wing surfaces with a
+small gas balloon. His first efforts to fly not being successful, he
+abandoned his invention and took to ballooning.
+
+Stentzel, an engineer of Hamburg, came next with a machine in the form
+of a gigantic butterfly. From tip to tip of its wings it measured 20
+feet, and their depth fore and aft was 5½ feet. The ribs of the wings
+were of steel and the web of silk, and they were slightly concave on
+the lower side. The rudder-tail was of two intersecting planes, one
+vertical and the other horizontal. It was operated by a carbonic-acid
+motor, and made 84 flaps of the wings per minute. The rush of air it
+produced was so great that any one standing near it would be almost
+swept off his feet. It did not reach a stage beyond the model, for it
+was able to lift only 75 lbs.
+
+[Illustration: Stentzel’s machine.]
+
+In 1843, the English inventor Henson built what is admitted to be the
+first aeroplane driven by motive power. It was 100 feet in breadth
+(spread) and 30 feet long, and covered with silk. The front edge was
+turned slightly upward. It had a rudder shaped like the tail of a
+bird. It was driven by two propellers run by a 20-horse-power engine.
+Henson succeeded only in flying on a down grade, doubtless because of
+the upward bend of the front of his plane. Later investigations have
+proven that the upper surface of the aeroplane must be convex to gain
+the lifting effect. This is one of the paradoxes of flying planes which
+no one has been able to explain.
+
+In 1845, Von Drieberg, in Germany, revived the sixteenth-century ideas
+of flying, with the quite original argument that since the legs of
+man were better developed muscularly than his arms, flying should be
+done with the legs. He built a machine on this plan, but no successful
+flights are recorded.
+
+In 1868, an experimenter by the name of Wenham added to the increasing
+sum of aeronautical knowledge by discovering that the lifting power of
+a large supporting surface may be as well secured by a number of small
+surfaces placed one above another. Following up these experiments, he
+built a flying machine with a series of six supporting planes made
+of linen fabric. As he depended upon muscular effort to work his
+propellers, he did not succeed in flying, but he gained information
+which has been valuable to later inventors.
+
+[Illustration: Von Drieberg’s machine; view from above.]
+
+[Illustration:
+
+    Wenham’s arrangement of many narrow surfaces in six tiers, or
+    decks. _a_, _a_, rigid framework; _b_, _b_, levers working
+    flapping wings; _e_, _e_, braces. The operator is lying prone.]
+
+The history of flying machines cannot be written without deferential
+mention of Horatio Phillips of England. The machine that he made in
+1862 resembled a large Venetian blind, 9 feet high and over 21 feet
+long. It was mounted on a carriage which travelled on a circular track
+600 feet long, and it was driven by a small steam engine turning a
+propeller. It lifted unusually heavy loads, although not large enough
+to carry a man. It seems to open the way for experiments with an
+entirely new arrangement of sustaining surfaces--one that has never
+since been investigated. Phillips’s records cover a series of most
+valuable experiments. Perhaps his most important work was in the
+determination of the most advantageous form for the surfaces of
+aeroplanes, and his researches into the correct proportion of motive
+power to the area of such surfaces. Much of his results have not yet
+been put to practical use by designers of flying machines.
+
+[Illustration: Phillips’s Flying Machine--built of narrow slats like a
+Venetian blind.]
+
+The year 1888 was marked by the construction by Sir Hiram Maxim of his
+great aeroplane which weighed three and one-half tons, and is said
+to have cost over $100,000. The area of the planes was 3,875 square
+feet, and it was propelled by a steam engine in which the fuel used
+was vaporized naphtha in a burner having 7,500 jets, under a boiler of
+small copper water tubes. With a steam pressure of 320 lbs. per square
+inch, the two compound engines each developed 180 horse-power, and each
+turned a two-bladed propeller 17½ feet in diameter. The machine was
+used only in making tests, being prevented from rising in the air by a
+restraining track. The thrust developed on trial was 2,164 lbs., and
+the lifting power was shown to have been in excess of 10,000 lbs. The
+restraining track was torn to pieces, and the machine injured by the
+fragments. The dynamometer record proved that a dead weight of 4½ tons,
+in addition to the weight of the machine and the crew of 4 men, could
+have been lifted. The stability, speed, and steering control were
+not tested. Sir Hiram Maxim made unnumbered experiments with models,
+gaining information which has been invaluable in the development of the
+aeroplane.
+
+[Illustration: View of a part of Maxim’s aeroplane, showing one of the
+immense propellers. At the top is a part of the upper plane.]
+
+The experiments of Otto Lilienthal in gliding with a winged structure
+were being conducted at this period. He held that success in flying
+must be founded upon proficiency in the art of balancing the
+apparatus in the air. He made innumerable glides from heights which
+he continually increased until he was travelling distances of nearly
+one-fourth of a mile from an elevation of 100 feet. He had reached the
+point where he was ready to install motive power to drive his glider
+when he met with a fatal accident. Besides the inspiration of his
+daring personal experiments in the air, he left a most valuable series
+of records and calculations, which have been of the greatest aid to
+other inventors in the line of artificial flight.
+
+[Illustration: Lilienthal in his biplane glider.]
+
+In 1896, Professor Langley, director of the Smithsonian Institution
+at Washington, made a test of a model flying machine which was the
+result of years of experimenting. It had a span of 15 feet, and a
+length of 8½ feet without the extended rudder. There were 4 sails or
+planes, 2 on each side, 30 inches in width (fore-and-aft measurement).
+Two propellers revolving in opposite directions were driven by a
+steam engine. The diameter of the propellers was 3 feet, and the
+steam pressure 150 lbs. per square inch. The weight of the machine
+was 28 lbs. It is said to have made a distance of 1 mile in 1 minute
+45 seconds. As Professor Langley’s experiments were conducted in
+strict secrecy, no authoritative figures are in existence. Later a
+larger machine was built, which was intended to carry a man. It had
+a spread of 46 feet, and was 35 feet in length. It was four years in
+building, and cost about $50,000. In the first attempt to launch it,
+from the roof of a house-boat, it plunged into the Potomac River. The
+explanation given was that the launching apparatus was defective. This
+was remedied, and a second trial made, but the same result followed.
+It was never tried again. This machine was really a double, or tandem,
+monoplane. The framework was built of steel tubing almost as thin
+as writing paper. Every rib and pulley was hollowed out to reduce
+the weight. The total weight of the engine and machine was 800 lbs.,
+and the supporting surface of the wings was 1,040 square feet. The
+aeroplanes now in use average from 2 to 4 lbs. weight to the square
+foot of sustaining surface.
+
+About the same time the French electrician Ader, after years of
+experimenting, with the financial aid of the French Government, made
+some secret trials of his machine, which had taken five years to build.
+It had two bat-like wings spreading 54 feet, and was propelled by two
+screws driven by a 4-cylinder steam engine which has been described as
+a marvel of lightness. The inventor claimed that he was able to rise
+to a height of 60 feet, and that he made flights of several hundred
+yards. The official tests, however, were unsatisfactory, and nothing
+further was done by either the inventor or the government to continue
+the experiments. The report was that in every trial the machines had
+been wrecked.
+
+The experiments of Lilienthal had excited an interest in his ideas
+which his untimely death did not abate. Among others, a young English
+marine engineer, Percy S. Pilcher, took up the problem of gliding
+flight, and by the device of using the power exerted by running boys
+(with a five-fold multiplying gear) he secured speed enough to float
+his glider horizontally in the air for some distance. He then built an
+engine which he purposed to install as motive power, but before this
+was done he was killed by a fall from his machine while in the air.
+
+[Illustration: Plan of Chanute’s movable-wing glider.]
+
+Before the death of Lilienthal his efforts had attracted the attention
+of Octave Chanute, a distinguished civil engineer of Chicago, who,
+believing that the real problem of the glider was the maintenance of
+equilibrium in the air, instituted a series of experiments along that
+line. Lilienthal had preserved his equilibrium by moving his body about
+as he hung suspended under the wings of his machine. Chanute proposed
+to accomplish the same end by moving the wings automatically. His
+attempts were partially successful. He constructed several types of
+gliders, one of these with two decks exactly in the form of the present
+biplane. Others had three or more decks. Upward of seven hundred glides
+were made with Chanute’s machines by himself and assistants, without
+a single accident. It is of interest to note that a month before the
+fatal accident to Lilienthal, Chanute had condemned that form of
+glider as unsafe.
+
+[Illustration: Chanute’s two-deck glider.]
+
+In 1897, A. M. Herring, who had been one of the foremost assistants of
+Octave Chanute, built a double-deck (biplane) machine and equipped it
+with a gasoline motor between the planes. The engine failed to produce
+sufficient power, and an engine operated by compressed air was tried,
+but without the desired success.
+
+In 1898, Lawrence Hargrave of Sydney, New South Wales, came into
+prominence as the inventor of the cellular or box kite. Following the
+researches of Chanute, he made a series of experiments upon the path
+of air currents under variously curved surfaces, and constructed some
+kites which, under certain conditions, would advance against a wind
+believed to be absolutely horizontal. From these results Hargrave was
+led to assert that “soaring sails” might be used to furnish propulsion,
+not only for flying machines, but also for ships on the ocean sailing
+against the wind. The principles involved remain in obscurity.
+
+During the years 1900 to 1903, the brothers Wright, of Dayton, Ohio,
+had been experimenting with gliders among the sand dunes of Kitty
+Hawk, North Carolina, a small hamlet on the Atlantic Coast. They
+had gone there because the Government meteorological department had
+informed them that at Kitty Hawk the winds blew more steadily than at
+any other locality in the United States. Toward the end of the summer
+of 1903, they decided that the time was ripe for the installation of
+motive power, and on December 17, 1903, they made their first four
+flights under power, the longest being 853 feet in 59 seconds--against
+a wind blowing nearly 20 miles an hour, and from a starting point on
+level ground.
+
+[Illustration: Wilbur Wright gliding at Kitty Hawk, N. C., in 1903.]
+
+During 1904 over one hundred flights were made, and changes in
+construction necessary to sail in circles were devised. In 1905, the
+Wrights kept on secretly with their practice and development of their
+machine, first one and then the other making the flights until both
+were equally proficient. In the latter part of September and early
+part of October, 1905, occurred a series of flights which the Wrights
+allowed to become known to the public. At a meeting of the Aeronautical
+Society of Great Britain, held in London on December 15, 1905, a letter
+from Orville Wright to one of the members was read. It was dated
+November 17, 1905, and an excerpt from it is as follows:
+
+“During the month of September we gradually improved in our practice,
+and on the 26th made a flight of a little over 11 miles. On the 30th we
+increased this to 12⅕th miles; on October 3, to 15⅓ miles; on October
+4, to 20¾ miles, and on October 5, to 24¼ miles. All these flights
+were made at about 38 miles an hour, the flight of October 5 occupying
+30 minutes 3 seconds. Landings were caused by the exhaustion of the
+supply of fuel in the flights of September 26 and 30, and October 8,
+and in those of October 3 and 4 by the heating of the bearings in the
+transmission, of which the oil cups had been omitted. But before the
+flight on October 5, oil cups had been fitted to all the bearings, and
+the small gasoline can had been replaced with one that carried enough
+fuel for an hour’s flight. Unfortunately, we neglected to refill the
+reservoir just before starting, and as a result the flight was limited
+to 38 minutes....
+
+[Illustration: A Wright machine in flight.]
+
+“The machine passed through all of these flights without the slightest
+damage. In each of these flights we returned frequently to the
+starting point, passing high over the heads of the spectators.”
+
+These statements were received with incredulity in many parts of
+Europe, the more so as the Wrights refused to permit an examination of
+their machine, fearing that the details of construction might become
+known before their patents were secured.
+
+[Illustration: The Archdeacon machine on the Seine.]
+
+During the summer of 1905, Captain Ferber and Ernest Archdeacon of
+Paris had made experiments with gliders. One of the Archdeacon machines
+was towed by an automobile, having a bag of sand to occupy the place
+of the pilot. It rose satisfactorily in the air, but the tail became
+disarranged, and it fell and was damaged. It was rebuilt and tried
+upon the waters of the Seine, being towed by a fast motor-boat at a
+speed of 25 miles an hour. The machine rose about 50 feet into the air
+and sailed for about 500 feet.
+
+Archdeacon gathered a company of young men about him who speedily
+became imbued with his enthusiasm. Among them were Gabriel Voisin,
+Louis Bleriot, and Leon Delagrange. The two former, working together,
+built and flew several gliders, and when Santos-Dumont made his
+historic flight of 720 feet with his multiple-cell machine on November
+13, 1906 (the first flight made in Europe), they were spurred to new
+endeavors.
+
+Within a few months Voisin had finished his first biplane, and
+Delagrange made his initial flight with it--a mere hop of 30 feet--on
+March 16, 1907.
+
+Bleriot, however, had his own ideas, and on August 6, 1907, he flew
+for 470 feet in a monoplane machine of the tandem type. He succeeded
+in steering his machine in a curved course, a feat which had not
+previously been accomplished in Europe.
+
+In October of the same year, Henri Farman, then a well-known automobile
+driver, flew the second Voisin biplane in a half circle of 253 feet--a
+notable achievement at that date.
+
+But Santos-Dumont had been pushing forward several different types of
+machines, and in November he flew first a biplane 500 feet, and a few
+days later a monoplane 400 feet.
+
+At this point in our story the past seems to give place to the
+present. The period of early development was over, and the year 1908
+saw the first of those remarkable exploits which are recorded in the
+chapter near the end of this work entitled, “Chronicle of Aviation
+Achievements.”
+
+It is interesting to note that the machines then brought out are those
+of to-day. Practically, it may be said that there has been no material
+change from the original types. More powerful engines have been put
+in them, and the frames strengthened in proportion, but the Voisin,
+the Bleriot, and the Wright types remain as they were at first. Other
+and later forms are largely modifications and combinations of their
+peculiar features.
+
+
+
+
+Chapter V.
+
+FLYING MACHINES: THE BIPLANE.
+
+    Successful types of aeroplanes--Distinguishing features--The
+    Wright biplane--Construction--New type--Five-passenger
+    machine--The Voisin biplane--New racing type--The Curtiss
+    biplane--The Cody biplane--The Sommer biplane--The
+    Baldwin biplane--New stabilizing plane--The Baddeck No.
+    2--Self-sustaining radiator--The Herring biplane--Stabilizing
+    fins.
+
+
+In the many contests for prizes and records, two types of flying
+machines have won distinctive places for themselves--the biplane and
+the monoplane. The appearance of other forms has been sporadic, and
+they have speedily disappeared without accomplishing anything which had
+not been better done by the two classes named.
+
+This fact, however, should not be construed as proving the futility of
+all other forms, nor that the ideal flying machine must be of one of
+these two prominent types. It is to be remembered that record-making
+and record-breaking is the most serious business in which any machines
+have so far been engaged; and this, surely, is not the field of
+usefulness to humanity which the ships of the air may be expected
+ultimately to occupy. It may yet be proved that, successful as these
+machines have been in what they have attempted, they are but transition
+forms leading up to the perfect airship of the future.
+
+[Illustration: The Wright biplane in flight.]
+
+The distinguishing feature of the biplane is not alone that it has two
+main planes, but that they are placed one above the other. The double
+(or tandem) monoplane also has two main planes, but they are on the
+same level, one in the rear of the other.
+
+A review of the notable biplanes of the day must begin with the Wright
+machine, which was not only the first with which flights were made, but
+also the inspiration and perhaps the pattern of the whole succeeding
+fleet.
+
+
+THE WRIGHT BIPLANE.
+
+The Wright biplane is a structure composed of two main surfaces,
+each 40 feet long and 6 feet 6 inches wide, set one above the other,
+parallel, and 6 feet apart. The planes are held rigidly at this
+distance by struts of wood, and the whole structure is trussed with
+diagonal wire ties. It is claimed by the Wrights that these dimensions
+have been proven by their experiments to give the maximum lift with
+the minimum weight.
+
+[Illustration:
+
+    Diagram showing the construction of the Wright biplane. The lever
+    _R_ is connected by the bar _A_ with the rudder gearing _C_, and
+    is pivoted at the bottom on a rolling shaft _B_, through which
+    the warping wires _W_^1, _W_^2 are operated. The semicircular
+    planes _F_ aid in stabilizing the elevator system.]
+
+The combination of planes is mounted on two rigid skids, or runners
+(similar to the runners of a sleigh), which are extended forward and
+upward to form a support for a pair of smaller planes in parallel,
+used as the elevator (for directing the course of the aeroplane upward
+or downward). It has been claimed by the Wrights that a rigid skid
+under-structure takes up the shock of landing, and checks the momentum
+at that moment, better than any other device. But it necessitated
+a separate starting apparatus, and while the starting impulse thus
+received enabled the Wrights to use an engine of less power (to keep
+the machine going when once started), and therefore of less dead
+weight, it proved a handicap to their machines in contests where they
+were met by competing machines which started directly with their own
+power. A later model of the Wright biplane is provided with a wheeled
+running gear, and an engine of sufficient power to raise it in the air
+after a short run on the wheels.
+
+Two propellers are used, run by one motor. They are built of wood, are
+of the two-bladed type, and are of comparatively large diameter--8
+feet. They revolve in opposite directions at a speed of 450
+revolutions per minute, being geared down by chain drive from the
+engine speed of 1,500 revolutions per minute.
+
+The large elevator planes in front have been a distinctive feature of
+the Wright machine. They have a combined area of 80 square feet, adding
+that much more lifting surface to the planes in ascending, for then
+the under side of their surfaces is exposed to the wind. If the same
+surfaces were in the rear of the main planes their top sides would have
+to be turned to the wind when ascending, and a depressing instead of a
+lifting effect would result.
+
+To the rear of the main planes is a rudder composed of two parallel
+vertical surfaces for steering to right or left.
+
+The feature essential to the Wright biplane, upon which the letters
+patent were granted, is the flexible construction of the tips of the
+main planes, in virtue of which they may be warped up or down to
+restore disturbed equilibrium, or when a turn is to be made. This
+warping of the planes changes the angle of incidence for the part of
+the plane which is bent. (The angle of incidence is that which the
+plane makes with the line in which it is moving. The bending downward
+of the rear edge would enlarge the angle of incidence, in that way
+increasing the compression of the air beneath, and lifting that end
+of the plane.) The wing-warping controls are actuated by the lever
+at the right hand of the pilot, which also turns the rudder at the
+rear--that which steers the machine to right or to left. The lever at
+the left hand of the pilot moves the elevating planes at the front of
+the machine.
+
+[Illustration: Sketch showing relative positions of planes and of the
+operator in the Wright machine: _A_, _A_, the main planes; _B_, _B_,
+the elevator planes. The motor is placed beside the operator.]
+
+The motor has 4 cylinders, and develops 25 to 30 horse-power, giving
+the machine a speed of 39 miles per hour.
+
+A newer model of the Wright machine is built without the large
+elevating planes in front, a single elevating plane being placed just
+back of the rear rudder. This arrangement cuts out the former lifting
+effect described above, and substitutes the depressing effect due to
+exposing the top of a surface to the wind.
+
+[Illustration: _Courtesy of N. Y. Times._
+
+The new model Wright biplane--without forward elevator.]
+
+The smallest of the Wright machines, popularly called the “Baby
+Wright,” is built upon this plan, and has proven to be the fastest of
+all the Wright series.
+
+
+THE VOISIN BIPLANE.
+
+While the Wrights were busily engaged in developing their biplane in
+America, a group of enthusiasts in France were experimenting with
+gliders of various types, towing them with high speed automobiles along
+the roads, or with swift motor-boats upon the Seine. As an outcome
+of these experiments, in which they bore an active part, the Voisin
+brothers began building the biplanes which have made them famous.
+
+As compared with the Wright machine, the Voisin aeroplane is of much
+heavier construction. It weighs 1,100 pounds. The main planes have a
+lateral spread of 37 feet 9 inches, and a breadth of 7 feet, giving
+a combined area of 540 square feet, the same as that of the Wright
+machine. The lower main plane is divided at the centre to allow the
+introduction of a trussed girder framework which carries the motor and
+propeller, the pilot’s seat, the controlling mechanism, and the running
+gear below; and it is extended forward to support the elevator. This
+is much lower than in the Wright machine, being nearly on the level of
+the lower plane. It is a single surface, divided at the centre, half
+being placed on each side of the girder. It has a combined area of 42
+square feet, about half of that of the Wright elevator, and it is only
+4 feet from the front edge of the main planes, instead of 10 feet as in
+the Wright machine. A framework nearly square in section, and about 25
+feet long, extends to the rear, and supports a cellular, or box-like,
+tail, which forms a case in which is the rudder surface for steering
+to right or to left.
+
+[Illustration: Diagram showing details of construction of the Voisin
+biplane. _C_, _C_, the curtains forming the stabilizing cells.]
+
+A distinctive feature of the Voisin biplane is the use of four vertical
+planes, or curtains, between the two main planes, forming two nearly
+square “cells” at the ends of the planes.
+
+At the rear of the main planes, in the centre, is the single propeller.
+It is made of steel, two-bladed, and is 8 feet 6 inches in diameter.
+It is coupled directly to the shaft of the motor, making with it 1,200
+revolutions per minute. The motor is of the V type, developing 50
+horse-power, and giving a speed of 37 miles per hour.
+
+[Illustration: Diagram showing the simplicity of control of the Voisin
+machine, all operations being performed by the wheel and its sliding
+axis.]
+
+The controls are all actuated by a rod sliding back and forth
+horizontally in front of the pilot’s seat, having a wheel at the end.
+The elevator is fastened to the rod by a crank lever, and is tilted
+up or down as the rod is pushed forward or pulled back. Turning
+the wheel from side to side moves the rudder in the rear. There are
+no devices for controlling the equilibrium. This is supposed to be
+maintained automatically by the fixed vertical curtains.
+
+[Illustration:
+
+    Voisin biplanes at the starting line at Rheims in August, 1909.
+    They were flown by Louis Paulhan, who won third prize for
+    distance, and Henri Rougier, who won fourth prize for altitude.
+    In the elimination races to determine the contestants for the
+    Bennett Cup, Paulhan won second place with the Voisin machine,
+    being defeated only by Tissandier with a Wright machine. Other
+    noted aviators who fly the Voisin machine are M. Bunau-Varilla
+    and the Baroness de la Roche.]
+
+The machine is mounted on two wheels forward, and two smaller wheels
+under the tail.
+
+This description applies to the standard Voisin biplane, which has
+been in much favor with many of the best known aviators. Recently
+the Voisins have brought out a new type in which the propeller has
+been placed in front of the planes, exerting a pulling force upon the
+machine, instead of pushing it as in the earlier type. The elevating
+plane has been removed to the rear, and combined with the rudder.
+
+A racing type also has been produced, in which the vertical curtains
+have been removed and a parallel pair of long, narrow ailerons
+introduced between the main planes on both sides of the centre. This
+machine, it is claimed, has made better than 60 miles per hour.
+
+The first Voisin biplane was built for Delagrange, and was flown by him
+with success.
+
+
+THE FARMAN BIPLANE.
+
+The second biplane built by the Voisins went into the hands of Henri
+Farman, who made many flights with it. Not being quite satisfied with
+the machine, and having an inventive mind, he was soon building a
+biplane after his own designs, and the Farman biplane is now one of the
+foremost in favor among both professional and amateur aviators.
+
+It is decidedly smaller in area of surface than the Wright and Voisin
+machines, having but 430 square feet in the two supporting planes. It
+has a spread of 33 feet, and the planes are 7 feet wide, and set 6 feet
+apart. In the Farman machine the vertical curtains of the Voisin have
+been dispensed with. The forward elevator is there, but raised nearly
+to the level of the upper plane, and placed 9 feet from the front edge
+of the main planes. To control the equilibrium, the two back corners
+of each plane are cut and hinged so that they hang vertically when not
+in flight. When in motion these flaps or ailerons stream out freely
+in the wind, assuming such position as the speed of the passing air
+gives them. They are pulled down by the pilot at one end or the other,
+as may be necessary to restore equilibrium, acting in very much the
+same manner as the warping tips of the Wright machine. A pair of tail
+planes are set in parallel on a framework about 20 feet in the rear of
+the main planes, and a double rudder surface behind them. Another model
+has hinged ailerons on these tail planes, and a single rudder surface
+set upright between them. These tail ailerons are moved in conjunction
+with those of the main planes.
+
+[Illustration: The Farman biplane, showing the position of the hinged
+ailerons when at rest. At full speed these surfaces stream out in the
+wind in line with the planes to which they are attached.]
+
+[Illustration: Diagram of the Farman biplane. A later type has the
+hinged ailerons also on the tail planes.]
+
+The motor has 4 cylinders, and turns a propeller made of wood, 8 feet 6
+inches in diameter, at a speed of 1,300 revolutions per minute--nearly
+three times as fast as the speed of the Wright propellers, which are
+about the same size. The propeller is placed just under the rear edge
+of the upper main plane, the lower one being cut away to make room
+for the revolving blades. The motor develops 45 to 50 horse-power, and
+drives the machine at a speed of 41 miles per hour.
+
+The “racing Farman” is slightly different, having the hinged ailerons
+only on one of the main planes. The reason for this is obvious. Every
+depression of the ailerons acts as a drag on the air flowing under the
+planes, increasing the lift at the expense of the speed.
+
+[Illustration: Sketch of Farman machine, showing position of operator.
+_A_, _A_, main planes; _B_, elevator; _C_, motor; _P_, tail planes.]
+
+The whole structure is mounted upon skids with wheels attached by a
+flexible connection. In case of a severe jar, the wheels are pushed up
+against the springs until the skids come into play.
+
+The elevator and the wing naps are controlled by a lever at the
+right hand of the pilot. This lever moves on a universal joint, the
+side-to-side movement working the flaps, and the forward-and-back
+motion the elevator. Steering to right or left is done with a bar
+operated by the feet.
+
+[Illustration: Henri Farman carrying a passenger across country.]
+
+Farman has himself made many records with his machine, and so have
+others. With a slightly larger and heavier machine than the one
+described, Farman carried two passengers a distance of 35 miles in one
+hour.
+
+
+THE CURTISS BIPLANE.
+
+This American rival of the Wright biplane is the lightest machine
+of this type so far constructed. The main planes are but 29 feet in
+spread, and 4 feet 6 inches in width, and are set not quite 5 feet
+apart. The combined area of the two planes is 250 square feet. The main
+planes are placed midway of the length of the fore-and-aft structure,
+which is nearly 30 feet. At the forward end is placed the elevator, and
+at the rear end is the tail--one small plane surface--and the vertical
+rudder surface in two parts, one above and the other below the tail
+plane. Equilibrium is controlled by changing the slant of two small
+balancing planes which are placed midway between the main planes at the
+outer ends, and in line with the front edges. These balancing planes
+are moved by a lever standing upright behind the pilot, having two arms
+at its upper end which turn forward so as to embrace his shoulders. The
+lever is moved to right or to left by the swaying of the pilot’s body.
+
+[Illustration: Glenn H. Curtiss in his machine ready to start. The fork
+of the balancing lever is plainly seen at his shoulders. Behind him is
+the radiator, with the engine still further back.]
+
+The motor is raised to a position where the shaft of the propeller is
+midway between the levels of the main planes, and within the line of
+the rear edges, so that they have to be cut away to allow the passing
+of the blades. The motor is of the V type, with 8 cylinders. It is 30
+horse-power and makes 1,200 revolutions per minute. The propeller is of
+steel, two-bladed, 6 feet in diameter, and revolves at the same speed
+as the shaft on which it is mounted. The high position of the engine
+permits a low running gear. There are two wheels under the rear edges
+of the main planes, and another is placed half-way between the main
+planes and the forward rudder, or elevator. A brake, operated by the
+pilot’s foot, acts upon this forward wheel to check the speed at the
+moment of landing.
+
+Another type of Curtiss machine has the ailerons set in the rear of the
+main planes, instead of between them.
+
+The Curtiss is the fastest of the biplanes, being excelled in speed
+only by some of the monoplanes. It has a record of 51 miles per hour.
+
+
+THE CODY BIPLANE.
+
+The Cody biplane has the distinction of being the first successful
+British aeroplane. It was designed and flown by Captain S. F. Cody, at
+one time an American, but for some years an officer in the British army.
+
+It is the largest and heaviest of all the biplanes, weighing about
+1,800 lbs., more than three times the weight of the Curtiss machine.
+Its main planes are 52 feet in lateral spread, and 7 feet 6 inches in
+width, and are set 9 feet apart. The combined area of these sustaining
+surfaces is 770 square feet. The upper plane is arched, so that the
+ends of the main planes are slightly closer together than at the centre.
+
+The elevator is in two parts placed end to end, about 12 feet in front
+of the main planes. They have a combined area of 150 square feet.
+Between them and above them is a small rudder for steering to right or
+left in conjunction with the large rudder at the rear of the machine.
+The latter has an area of 40 square feet.
+
+There are two small balancing planes, set one at each end of the main
+planes, their centres on the rear corner struts, so that they project
+beyond the tips of the planes and behind their rear lines.
+
+[Illustration: The Cody biplane in flight. Captain Cody has both hands
+raised above his head, showing the automatic stability of his machine.]
+
+The biplane is controlled by a lever rod having a wheel at the end.
+Turning the wheel moves the rudders; pushing or pulling the wheel works
+the elevator; moving the wheel from side to side moves the balancing
+planes.
+
+There are two propellers, set one on each side of the engine, and well
+forward between the main planes. They are of wood, of the two-bladed
+type, 7 feet in diameter. They are geared down to make 600 revolutions
+per minute. The motor has 8 cylinders and develops 80 horse-power at
+1,200 revolutions per minute.
+
+The machine is mounted on a wheeled running gear, two wheels under the
+front edge of the main planes and one a short distance forward in the
+centre. There is also a small wheel at each extreme end of the lower
+main plane.
+
+The Cody biplane has frequently carried a passenger, besides the pilot,
+and is credited with a speed of 38 miles per hour.
+
+The first aeroplane flights ever made in England were by Captain Cody
+on this biplane, January 2, 1909.
+
+
+THE SOMMER BIPLANE.
+
+The Sommer biplane is closely similar to the Farman machine, but has
+the hinged ailerons only on the upper plane. Another difference is that
+the tail has but one surface, and the rudder is hung beneath it. Its
+dimensions are:--Spread of main planes, 34 feet; depth (fore-and-aft),
+6 feet 8 inches; they are set 6 feet apart. The area of the main planes
+is 456 square feet; area of tail, 67 square feet; area of rudder, 9
+square feet. It is driven by a 50-horsepower Gnome motor, turning an
+8-foot, two-bladed propeller.
+
+M. Sommer has flown with three passengers, a total weight of 536 lbs.,
+besides the weight of the machine.
+
+
+THE BALDWIN BIPLANE.
+
+The Baldwin biplane, designed by Captain Thomas S. Baldwin, the
+distinguished balloonist, resembles the Farman type in some features,
+and the Curtiss in others. It has the Curtiss type of ailerons, set
+between the wings, but extending beyond them laterally. The elevator is
+a single surface placed in front of the machine, and the tail is of the
+biplane type with the rudder between. The spread of the main planes is
+31 feet 3 inches, and their depth 4 feet 6 inches. A balancing plane of
+9 square feet is set upright (like a fin) above the upper main plane,
+on a swivel. This is worked by a fork fitting on the shoulders of the
+pilot, and is designed to restore equilibrium by its swinging into
+head-resistance on one side or the other as may be necessary.
+
+[Illustration: The Baldwin biplane, showing balancing plane above upper
+main plane.]
+
+The motive power is a 4-cylinder Curtiss motor, which turns a propeller
+7 feet 6 inches in diameter, set just within the rear line of the main
+planes, which are cut away to clear the propeller blades.
+
+
+THE BADDECK BIPLANE.
+
+The newest biplane of the Aerial Experiment Association follows in
+general contour its successful precursor, the “Silver Dart,” with
+which J. A. D. McCurdy made many records. The “Baddeck No. 2” is of
+the biplane type, and both the planes are arched toward each other.
+They have a spread of 40 feet, and are 7 feet in depth at the centre,
+rounding to 5 feet at the ends, where the wing tips, 5 feet by 5 feet,
+are hinged. The elevator is also of the biplane type, two surfaces each
+12 feet long and 28 inches wide, set 30 inches apart. This is mounted
+15 feet in front of the main planes. The tail is mounted 11 feet in the
+rear of the main planes, and is the same size and of the same form as
+the elevator.
+
+The controls are operated by the same devices as in the Curtiss
+machine. The propeller is 7 feet 8 inches in diameter, and is turned
+by a six-cylinder automobile engine of 40 horse-power running at 1,400
+revolutions per minute. The propeller is geared down to run at 850
+revolutions per minute. The motor is placed low down on the lower
+plane, but the propeller shaft is raised to a position as nearly as
+possible that of the centre of resistance of the machine. The speed
+attained is 40 miles per hour.
+
+[Illustration: The McCurdy biplane, “Baddeck No. 2.”]
+
+A unique feature of the mechanism is the radiator, which is built of
+30 flattened tubes 7 feet 6 inches long, and 3 inches wide, and very
+thin. They are curved from front to rear like the main planes, and give
+sufficient lift to sustain their own weight and that of the water
+carried for cooling the cylinders. The running gear is of three wheels
+placed as in the Curtiss machine. The “Baddeck No. 2” has made many
+satisfactory flights with one passenger besides the pilot.
+
+
+THE HERRING BIPLANE.
+
+At the Boston Aircraft Exhibition in February, 1910, the Herring
+biplane attracted much attention, not only because of its superiority
+of mechanical finish, but also on account of its six triangular
+stabilizing fins set upright on the upper plane. Subsequent trials
+proved that this machine was quite out of the ordinary in action. It
+rose into the air after a run of but 85 feet, and at a speed of only
+22 miles per hour, and made a 40-degree turn at a tipping angle of 20
+degrees. As measured by the inventor, the machine rose in the air with
+the pilot (weighing 190 lbs.), with a thrust of 140 lbs., and required
+only a thrust of from 80 to 85 lbs. to keep it flying.
+
+The spread of the planes is 28 feet, and they are 4 feet in depth,
+with a total supporting surface of 220 feet. A 25 horse-power Curtiss
+motor turns a 4-bladed propeller of 6 feet diameter and 5-foot pitch
+(designed by Mr. Herring) at the rate of 1,200 revolutions per minute.
+
+[Illustration: The L. A. W. (League of American Wheelmen) biplane at
+the Boston Aircraft Exhibition, February, 1910. Note the peculiar
+curve of the divided planes. The motor is of the rotating type, of 50
+horse-power.]
+
+The elevator consists of a pair of parallel surfaces set upon hollow
+poles 12 feet in front of the main planes. The tail is a single surface.
+
+The stabilizing fins act in this manner: when the machine tips to one
+side, it has a tendency to slide down an incline of air toward the
+ground. The fins offer resistance to this sliding, retarding the upper
+plane, while the lower plane slides on and swings as a pendulum into
+equilibrium again.
+
+
+THE BREGUET BIPLANE.
+
+The Breguet biplane is conspicuous in having a biplane tail of so
+large an area as to merit for the machine the title “tandem biplane.”
+The main planes have a spread of 41 feet 8 inches, and an area of 500
+square feet. The tail spreads 24 feet, and its area is about 280 square
+feet. The propeller is three-bladed, 8 feet in diameter, and revolves
+at a speed of 1,200 revolutions per minute. It is placed in front of
+the main plane, after the fashion of the monoplanes. The motive power
+is an 8-cylinder R-E-P engine, developing 55 horse-power.
+
+[Illustration: _Courtesy of N. Y. Sun._
+
+The Seddon tandem biplane, constructed by Lieutenant Seddon of the
+British Navy. The area of its planes is 2,000 square feet. Compare its
+size with that of the monoplane in the background. It is intended to
+carry ten persons.]
+
+[Illustration:
+
+  Wright biplane.      Curtiss biplane.
+
+Comparative build and area of prominent American biplanes.]
+
+[Illustration:
+
+  Voisin biplane.      Breguet biplane.
+
+Comparative build and area of prominent European biplanes.]
+
+
+
+
+Chapter VI.
+
+FLYING MACHINES: THE MONOPLANE.
+
+    The common goal--Interchanging features--The Bleriot
+    machine--First independent flyer--Construction and controls--The
+    “Antoinette”--Large area--Great stability--Santos-Dumont’s
+    monoplane--Diminutive size--R-E-P monoplane--encased
+    structure--Hanriot machine--Boat body--Sturdy build--Pfitzner
+    machine--Lateral type--Thrusting propeller--Fairchild,
+    Burlingame, Cromley, Chauviere, Vendome, and Moisant monoplanes.
+
+
+In all the ardent striving of the aviators to beat each other’s
+records, a surprisingly small amount of personal rivalry has been
+developed. Doubtless this is partly because their efforts to perform
+definite feats have been absorbing; but it must also be that these men,
+who know that they face a possible fall in every flight they make,
+realize that their competitors are as brave as themselves in the face
+of the same danger; and that they are actually accomplishing marvellous
+wonders even if they do no more than just escape disastrous failure.
+Certain it is that each, realizing the tremendous difficulties all must
+overcome, respects the others’ ability and attainments.
+
+Consequently we do not find among them two distinctly divergent
+schools of adherents, one composed of the biplanists, the other of the
+monoplanists. Nor are the two types of machines separated in this book
+for any other purpose than to secure a clearer understanding of what
+is being achieved by all types in the progress toward the one common
+goal--the flight of man.
+
+The distinctive feature of the monoplane is that it has but one main
+plane, or spread of surface, as contrasted with the two planes, one
+above the other, of the biplane. Besides the main plane, it has a
+secondary plane in the rear, called the tail. The office of this tail
+is primarily to secure longitudinal, or fore-and-aft, balance; but
+the secondary plane has been so constructed that it is movable on a
+horizontal axis, and is used to steer the machine upward or downward.
+While most of the biplanes now have a horizontal tail-plane, they were
+not at first so provided, but carried the secondary plane (or planes)
+in front of the main planes. Even in the latest type brought out by the
+conservative Wright brothers, the former large-surfaced elevator in
+front has been removed, and a much smaller tail-plane has been added in
+the rear, performing the same function of steering the machine up or
+down, but also providing the fore-and-aft stabilizing feature formerly
+peculiar to the monoplane. Another feature heretofore distinctively
+belonging to the monoplane has been adopted by some of the newer
+biplanes, that of the traction propeller--pulling the machine behind it
+through the air, instead of pushing it along by a thrusting propeller
+placed behind the main planes.
+
+The continual multiplication of new forms of the monoplane makes it
+possible to notice only those which exhibit the wider differences.
+
+
+THE BLERIOT MONOPLANE.
+
+The Bleriot monoplane has the distinction of being the first wholly
+successful flying machine. Although the Wright machine was making
+flights years before the Bleriot had been built, it was still dependent
+upon a starting device to enable it to leave the ground. That is, the
+Wright machine was not complete in itself, and was entirely helpless
+at even a short distance from its starting tower, rail, and car, which
+it was unable to carry along. Because of its completeness, M. Bleriot
+was able to drive his machine from Toury to Artenay, France (a distance
+of 8¾ miles) on October 31, 1908, make a landing, start on the return
+trip, make a second landing, and again continue his journey back to
+Toury, all under his own unassisted power. This feat was impossible to
+the Wright machine as it was then constructed, thus leaving the Bleriot
+monoplane in undisputed pre-eminence in the history of aviation.
+
+[Illustration: A Bleriot monoplane, “No. XI,” in flight.]
+
+At a little distance, where the details of construction are not
+visible, the Bleriot machine has the appearance of a gigantic bird. The
+sustaining surface, consisting of a single plane, is divided into two
+wings made of a stiff parchment-like material, mounted one on each side
+of a framework of the body, which is built of mahogany and whitewood
+trussed with diagonal ties of steel wire.
+
+The main plane has a lateral spread of 28 feet and a depth of 6 feet,
+and is rounded at the ends. It has an area of about 150 square feet,
+and is slightly concave on the under side. The tail-plane is 6 feet
+long and 2 feet 8 inches in depth; at its ends are the elevators,
+consisting of pivoted wing tips each about 2 feet 6 inches square
+with rounded extremities. The rudder for steering to left or right
+is mounted at the extreme rear end of the body, and has an area of 9
+square feet.
+
+[Illustration: The Bleriot “No. XII.,” showing new form of tail, and
+the complete encasing with fabric.]
+
+The body is framed nearly square in front and tapers to a wedge-like
+edge at the rear. It extends far enough in front of the main plane to
+give room for the motor and propeller. The seat for the pilot is on a
+line with the rear edge of the main plane, and above it. The forward
+part of the body is enclosed with fabric.
+
+[Illustration: Forward chassis of Bleriot monoplane, showing caster
+mounting of wheels. The framing of the body is shown by the dotted
+lines.]
+
+The machine is mounted on three wheels attached to the body: two at
+the front, with a powerful spring suspension and pivoted like a caster,
+and the other rigidly at a point just forward of the rudders.
+
+The lateral balance is restored by warping the tips of the main plane;
+if necessary, the elevator tips at the rear may be operated to assist
+in this. All the controls are actuated by a single lever and a drum to
+which the several wires are attached.
+
+[Illustration:
+
+    Diagram of Bleriot “No. XI.,” from the rear. _A_, _A_, main
+    plane; _B_, tail; _C_, body; _D_, _D_, wing tips of tail; _E_,
+    rudder; _H_, propeller; _M_, motor; _O_, axis of wing tips; _R_,
+    radiator; _a_, _a_, _b_, _b_, spars of wings; _h_, _h_, guy
+    wires; _p_, _k_, truss.]
+
+The motors used on the Bleriot machines have varied in type and power.
+In the “No. XI.,” with which M. Bleriot crossed the English Channel,
+the motor was a 3-cylinder Anzani engine, developing 24 horse-power at
+1,200 revolutions per minute. The propeller was of wood, 2-bladed, and
+6 feet 9 inches in diameter. It was mounted directly on the shaft, and
+revolved at the same speed, giving the machine a velocity of 37 miles
+per hour. This model has also been fitted with a 30 horse-power R-E-P
+(R. Esnault-Pelterie) motor, having 7 cylinders. The heavier type “No.
+XII.” has been fitted with the 50 horse-power Antoinette 8-cylinder
+engine, or the 7-cylinder rotating Gnome engine, also of 50 horse-power.
+
+[Illustration: Sketches showing relative size, construction, and
+position of pilot in the Bleriot machines; “No. XI.” (the upper), and
+“No. XII.” (the lower).]
+
+The total weight of the “No. XI.” monoplane is 462 pounds, without the
+pilot.
+
+
+THE ANTOINETTE MONOPLANE.
+
+The Antoinette is the largest and heaviest of the monoplanes. It
+was designed by M. Levavasseur, and has proved to be one of the
+most remarkable of the aeroplanes by its performances under adverse
+conditions; notably, the flight of Hubert Latham in a gale of 40 miles
+per hour at Blackpool in October, 1909.
+
+The Antoinette has a spread of 46 feet, the surface being disposed
+in two wings set at a dihedral angle; that is, the outer ends of the
+wings incline upward from their level at the body, so that at the front
+they present the appearance of a very wide open “V.” These wings are
+trapezoidal in form, with the wider base attached to the body, where
+they are 10 feet in depth (fore and aft). They are 7 feet in depth at
+the tips, and have a total combined area of 377 square feet. The great
+depth of the wings requires that they be made proportionally thick to
+be strong enough to hold their form. Two trussed spars are used in each
+wing, with a short mast on each, half-way to the tip, reaching below
+the wing as well as above it. To these are fastened guy wires, making
+each wing an independent truss. A mast on the body gives attachment
+for guys which bind the whole into a light and rigid construction. The
+framework of the wings is covered on both sides with varnished fabric.
+
+[Illustration: The Antoinette monoplane in flight.]
+
+The body is of triangular section. It is a long girder; at the front,
+in the form of a pyramid, expanding to a prism at the wings, and
+tapering toward the tail. It is completely covered with the fabric,
+which is given several coats of varnish to secure the minimum of skin
+friction.
+
+[Illustration: Diagram showing construction of the Antoinette
+monoplane.]
+
+The tail is 13 feet long and 9 feet wide, in the form of a
+diamond-shaped kite. The rear part of it is hinged to be operated as
+the elevator. There is a vertical stabilizing fin set at right angles
+to the rigid part of the tail. The rudder for steering to right or
+left is in two triangular sections, one above and the other below the
+tail-plane. The entire length of the machine is 40 feet, and its weight
+is 1,045 pounds.
+
+It is fitted with a motor of the “V” type, having 8 cylinders, and
+turning a 2-bladed steel propeller 1,100 revolutions per minute,
+developing from 50 to 55 horse-power.
+
+The control of the lateral balance is by ailerons attached to the rear
+edges of the wings at their outer ends. These are hinged, and may be
+raised as well as lowered as occasion demands, working in opposite
+directions, and thus doubling the effect of similar ailerons on the
+Farman machine, which can only be pulled downward.
+
+The machine is mounted on two wheels under the centre of the main
+plane, with a flexible wood skid projecting forward. Another skid is
+set under the tail.
+
+It is claimed for the Antoinette machine that its inherent stability
+makes it one of the easiest of all for the beginner in aviation. With
+as few as five lessons many pupils have become qualified pilots, even
+winning prizes against competitors of much wider experience.
+
+[Illustration: Diagrams showing comparative size and position of
+surfaces and structure of the Bleriot (left) and Antoinette (right)
+monoplanes.]
+
+
+THE SANTOS-DUMONT MONOPLANE.
+
+This little machine may be called the “runabout” of the aeroplanes. It
+has a spread of only 18 feet, and is but 20 feet in total length. Its
+weight is about 245 pounds.
+
+The main plane is divided into two wings, which are set at the body
+at a dihedral angle, but curve downward toward the tips, forming an
+arch. The depth of the wings at the tips is 6 feet. For a space on each
+side of the centre they are cut away to 5 feet in depth, to allow the
+propeller to be set within their forward edge. The total area of the
+main plane is 110 square feet.
+
+The tail-plane is composed of a vertical surface and a horizontal
+surface intersecting. It is arranged so that it may be tilted up or
+down to serve as an elevator, or from side to side as a rudder. Its
+horizontal surface has an area of about 12 square feet.
+
+The engine is placed above the main plane and the pilot’s seat below
+it. The body is triangular in section, with the apex uppermost,
+composed of three strong bamboo poles with cross-pieces held in place
+by aluminum sockets, and cross braced with piano wire.
+
+[Illustration: Santos-Dumont’s _La Demoiselle_ in flight.]
+
+The motor is of the opposed type, made by Darracq, weighing only 66
+pounds, and developing 30 horse-power at 1,500 revolutions per minute.
+The propeller is of wood, 2-bladed, and being mounted directly on the
+shaft of the motor, revolves at the same velocity. The speed of the
+Santos-Dumont machine is 37 miles per hour.
+
+[Illustration: The Darracq motor and propeller of the Santos-Dumont
+machine. The conical tank in the rear of the pilot’s seat holds the
+gasoline.]
+
+The lateral balance is preserved by a lever which extends upward and
+enters a long pocket sewed on the back of the pilot’s coat. His leaning
+from side to side warps the rear edges of the wings at their tips. The
+elevator is moved by a lever, and the rudder by turning a wheel.
+
+While this machine has not made any extended flights, Santos-Dumont has
+travelled in the aggregate upward of 2,000 miles in one or another of
+this type.
+
+The plans, with full permission to any one to build from them, he gave
+to the public as his contribution to the advancement of aviation.
+Several manufacturers are supplying them at a cost much below that of
+an automobile.
+
+[Illustration: Sketch showing position of pilot in Santos-Dumont
+machine. _A_, main plane; _B_, tail plane; _C_, motor.]
+
+
+THE R-E-P MONOPLANE.
+
+The Robert Esnault-Pelterie (abbreviated by its inventor to R-E-P)
+monoplane, viewed from above, bears a striking resemblance to a bird
+with a fan-shaped tail. It is much shorter in proportion to its spread
+than any other monoplane, and the body being entirely covered with
+fabric, it has quite a distinct appearance.
+
+The plane is divided into two wings, in form very much like the wings
+of the Antoinette machine. Their spread, however, is but 35 feet. Their
+depth at the body is 8 feet 6 inches, and at the tips, 5 feet. Their
+total combined area is 226 square feet.
+
+The body of the R-E-P machine has much the appearance of a boat, being
+wide at the top and coming to a sharp keel below. The boat-like prow in
+front adds to this resemblance. As the body is encased in fabric, these
+surfaces aid in maintaining vertical stability.
+
+A large stabilizing fin extends from the pilot’s seat to the tail. The
+tail is comparatively large, having an area of 64 square feet. Its rear
+edge may be raised or lowered to serve as an elevator. The rudder for
+steering to right or left is set below in the line of the body, as in a
+boat. It is peculiar in that it is of the “compensated” type; that is,
+pivoted near the middle of its length, instead of at the forward end.
+
+The control of the lateral balance is through warping the wings. This
+is by means of a lever at the left hand of the pilot, with a motion
+from side to side. The same lever moved forward or backward controls
+the elevator. The steering lever is in front of the pilot’s seat, and
+moves to right or to left.
+
+[Illustration: Elevation, showing large stabilizing fin; boat-like body
+encased in fabric; and compensated rudder, pivoted at the rear end of
+the fin.]
+
+[Illustration: Plan, showing comparative spread of surfaces, and the
+attachment of wheels at the wing tips.
+
+Graphic sketch showing elevation and plan of the R-E-P monoplane.]
+
+The motor is an invention of M. Esnault-Pelterie, and may be of 5, 7,
+or 10 cylinders, according to the power desired. The cylinders are
+arranged in two ranks, one in the rear of the other, radiating outward
+from the shaft like spokes in a wheel. The propeller is of steel,
+4-bladed, and revolves at 1,400 revolutions per minute, developing 35
+horse-power, and drawing the machine through the air at a speed of 47
+miles per hour.
+
+
+THE HANRIOT MONOPLANE.
+
+Among the more familiar machines which have been contesting for records
+at the various European meets during the season of 1910, the Hanriot
+monoplane earned notice for itself and its two pilots, one of them the
+fifteen-year-old son of the inventor. At Budapest the Hanriot machine
+carried off the honors of the occasion with a total of 106 points for
+“best performances,” as against 84 points for the Antoinette, and 77
+points for the Farman biplane. A description of its unusual features
+will be of interest by way of comparison.
+
+In general appearance it is a cross between the Bleriot and the
+Antoinette, the wings being shaped more like the latter, but rounded
+at the rear of the tips like the Bleriot. Its chief peculiarity is in
+the body of the machine, which is in form very similar to a racing
+shell--of course with alterations to suit the requirements of the
+aeroplane. Its forward part is of thin mahogany, fastened upon ash
+ribs, with a steel plate covering the prow. The rear part of the
+machine is covered simply with fabric.
+
+The spread of the plane is 24 feet 7 inches, and it has an area of 170
+square feet. The length of the machine, fore-and-aft, is 23 feet. Its
+weight is 463 pounds. It is mounted on a chassis having both wheels
+and skids, somewhat like that of the Farman running gear, but with two
+wheels instead of four.
+
+The Hanriot machine is sturdily built all the way through, and has
+endured without damage some serious falls and collisions which would
+have wrecked another machine.
+
+It is fitted either with a Darracq or a Clerget motor, and speeds at
+about 44 miles per hour.
+
+
+THE PFITZNER MONOPLANE.
+
+The Pfitzner monoplane has the distinction of being the first American
+machine of the single-plane type. It was designed and flown by the
+late Lieut. A. L. Pfitzner, and, though meeting with many mishaps, has
+proved itself worthy of notice by its performances, through making use
+of an entirely new device for lateral stability. This is the sliding
+wing tip, by which the wing that tends to fall from its proper level
+may be lengthened by 15 inches, the other wing being shortened as much
+at the same time.
+
+There is no longitudinal structure, as in the other monoplanes, the
+construction being transverse and built upon four masts set in the
+form of a square, 6 feet apart, about the centre. These are braced by
+diagonal struts, and tied with wires on the edges of the squares. They
+also support the guys reaching out to the tips of the wings.
+
+[Illustration: The Pfitzner monoplane from the rear, showing the
+sliding wing tips; dihedral angle of the wings; square body; and
+transverse trussed construction.]
+
+The plane proper is 31 feet in spread, to which the wing tips add 2½
+feet, and is 6 feet deep, giving a total area of 200 square feet. A
+light framework extending 10 feet in the rear carries a tail-plane 6
+feet in spread and 2 feet in depth. Both the elevator and the rudder
+planes are carried on a similar framework, 14 feet in front of the main
+plane.
+
+[Illustration: The Pfitzner monoplane, showing the structure of the
+body; the two conical gasoline tanks above; the propeller in the rear.
+Lieutenant Pfitzner at the wheel.]
+
+The wings of the main plane incline upward from the centre toward the
+tips, and are trussed by vertical struts and diagonal ties.
+
+The motor is placed in the rear of the plane, instead of in front, as
+in all other monoplanes. It is a 4-cylinder Curtiss motor, turning a
+6-foot propeller at 1,200 revolutions per minute, and developing 25
+horse-power.
+
+The Pfitzner machine has proved very speedy, and has made some
+remarkably sharp turns on an even keel.
+
+
+OTHER MONOPLANES.
+
+Several machines of the monoplane type have been produced, having some
+feature distinct from existing forms. While all of these have flown
+successfully, few of them have made any effort to be classed among the
+contestants for honors at the various meets.
+
+One of these, the Fairchild monoplane, shows resemblances to the R-E-P,
+the Antoinette, and the Bleriot machines, but differs from them all
+in having two propellers instead of one; and these revolve in the
+same direction, instead of in contrary directions, as do those of all
+other aeroplanes so equipped. The inventor claims that there is little
+perceptible gyroscopic effect with a single propeller, and even less
+with two. The propeller shafts are on the level of the plane, but the
+motor is set about 5 feet below, connections being made by a chain
+drive.
+
+[Illustration: The Beach type of the Antoinette, an American
+modification of the French machine, at the Boston Exhibition, 1910.]
+
+The Burlingame monoplane has several peculiarities. Its main plane is
+divided into two wings, each 10 feet in spread and 5 feet in depth,
+and set 18 inches apart at the body. They are perfectly rigid. The
+tail is in two sections, each 4 feet by 5 feet, and set with a gap of
+6 feet between the sections, in which the rudder is placed. Thus the
+spread of the tail from tip to tip is 16 feet, as compared with the 21½
+foot spread of the main plane. The sections of the tail are operated
+independently, and are made to serve as ailerons to control the lateral
+balance, and also as the elevator.
+
+The Cromley monoplane, another American machine, is modelled after the
+Santos-Dumont _Demoiselle_. It has a main plane divided into two wings,
+each 9 feet by 6 feet 6 inches, with a gap of 2 feet between at the
+body; the total area being 117 square feet. At the rear of the outer
+ends are hinged ailerons, like those of the Farman biplane, to control
+the lateral balance. The tail is 12 feet in the rear, and is of the
+“box” type, with two horizontal surfaces and two vertical surfaces.
+This is mounted with a universal joint, so that it can be moved in any
+desired direction. The complete structure, without the motor, weighs
+but 60 pounds.
+
+The Chauviere monoplane is distinct in having a rigid spar for the
+front of the plane, but no ribs. The surface is allowed to spread out
+as a sail and take form from the wind passing beneath. The rear edges
+may be pulled down at will to control the lateral balance. It is driven
+by twin screws set far back on the body, nearly to the tail.
+
+[Illustration:
+
+    The Morok monoplane at the Boston Exhibition. It has the body of
+    the Bleriot, the wings of the Santos-Dumont, and the sliding wing
+    tips of the Pfitzner.]
+
+The smallest and lightest monoplane in practical use is that of M.
+Raoul Vendome. It is but 16 feet in spread, and is 16 feet fore and
+aft. It is equipped with a 12 horse-power motor, and flies at a speed
+of nearly 60 miles per hour. Without the pilot, its entire weight is
+but 180 pounds. The wings are pivoted so that their whole structure may
+be tilted to secure lateral balance.
+
+The new Moisant monoplane is built wholly of metal. The structure
+throughout is of steel, and the surfaces of sheet aluminum in a
+succession of small arches from the centre to the tips. No authentic
+reports of its performances are available.
+
+In the Tatin monoplane, also called the Bayard-Clement, the main plane
+is oval in outline, and the tail a smaller oval. The surfaces are
+curved upward toward the tips for nearly half their length in both
+the main plane and the tail. The propeller is 8½ feet in diameter,
+and is turned by a Clerget motor, which can be made to develop 60
+horse-power for starting the machine into the air, and then cut down to
+30 horse-power to maintain the flight.
+
+
+
+
+Chapter VII.
+
+FLYING MACHINES: OTHER FORMS.
+
+    The triplane--The quadruplane--The multiplane--Helicopters--Their
+    principle--Obstacles to be overcome--The Cornu helicopter--The
+    Leger helicopter--The Davidson gyropter--The Breguet
+    gyroplane--The de la Hault ornithopter--The Bell
+    tetrahedrons--The Russ flyer.
+
+
+While the efforts of inventors have been principally along the lines
+of the successful monoplanes and biplanes, genius and energy have also
+been active in other directions. Some of these other designs are not
+much more than variations from prevailing types, however.
+
+Among these is the English Roe triplane, which is but a biplane
+with an extra plane added; the depths of all being reduced to give
+approximately the same surface as the biplane of the same carrying
+power. The tail is also of the triplane type, and has a combined area
+of 160 square feet--just half that of the main planes. The triplane
+type has long been familiar to Americans in the three-decker glider
+used extensively by Octave Chanute in his long series of experiments
+at Chicago.
+
+[Illustration: The Roe triplane in flight.]
+
+The quadruplane of Colonel Baden-Powell, also an English type, is
+practically the biplane with unusually large forward and tail planes.
+
+The multiplane of Sir Hiram Maxim should also be remembered, although
+he never permitted it to have free flight. His new multiplane, modelled
+after the former one, but equipped with an improved gasoline motor
+instead of the heavy steam-engine of the first model, will doubtless be
+put to a practical test when experiments with it are completed.
+
+[Illustration: Sir Hiram Maxim standing beside his huge multiplane.]
+
+Quite apart from these variants of the aeroplanes are the helicopters,
+ornithopters, gyropters, gyroplanes, and tetrahedral machines.
+
+
+HELICOPTERS.
+
+The result aimed at in the helicopter is the ability to rise vertically
+from the starting point, instead of first running along the ground
+for from 100 to 300 feet before sufficient speed to rise is attained,
+as the aeroplanes do. The device employed to accomplish this result is
+a propeller, or propellers, revolving horizontally above the machine.
+After the desired altitude is gained it is proposed to travel in any
+direction by changing the plane in which the propellers revolve to one
+having a small angle with the horizon.
+
+[Illustration:
+
+    The force necessary to keep the aeroplane moving in its
+    horizontal path is the same as that required to move the
+    automobile of equal weight up the same gradient--much less than
+    its total weight.]
+
+The great difficulty encountered with this type of machine is that the
+propellers must lift the entire weight. In the case of the aeroplane,
+the power of the engine is used to slide the plane up an incline of
+air, and for this much less power is required. For instance, the weight
+of a Curtiss biplane with the pilot on board is about 700 pounds,
+and this weight is easily slid up an inclined plane of air with a
+propeller thrust of about 240 pounds.
+
+Another difficulty is that the helicopter screws, in running at the
+start before they can attain speed sufficient to lift their load, have
+established downward currents of air with great velocity, in which the
+screws must run with much less efficiency. With the aeroplanes, on the
+contrary, their running gear enables them to run forward on the ground
+almost with the first revolution of the propeller, and as they increase
+their speed the currents--technically called the “slip”--become less
+and less as the engine speed increases.
+
+In the Cornu helicopter, which perhaps has come nearer to successful
+flight than any other, these downward currents are checked by
+interposing planes below, set at an angle determined by the operator.
+The glancing of the currents of air from the planes is expected to
+drive the helicopter horizontally through the air. At the same time
+these planes offer a large degree of resistance, and the engine power
+must be still further increased to overcome this, while preserving the
+lift of the entire weight. With an 8-cylinder Antoinette motor, said
+to be but 24 horse-power, turning two 20-foot propellers, the machine
+is reported as lifting itself and two persons--a total weight of 723
+pounds--to a height of 5 feet, and sustaining itself for 1 minute. Upon
+the interposing of the planes to produce the horizontal motion the
+machine came immediately to the ground.
+
+[Illustration: Diagram showing principle of the Cornu helicopter. _P_,
+_P_, propelling planes. The arrow shows direction of travel with planes
+at angle shown.]
+
+This performance must necessarily be compared with that of the
+aeroplanes, as, for instance, the Wright machine, which, with a 25 to
+30 horse-power motor operating two 8-foot propellers, raises a weight
+of 1,050 pounds and propels it at a speed of 40 miles an hour for
+upward of 2 hours.
+
+Another form of helicopter is the Leger machine, so named after its
+French inventor. It has two propellers which revolve on the same
+vertical axis, the shaft of one being tubular, encasing that of the
+other. By suitable gearing this vertical shaft may be inclined after
+the machine is in the air in the direction in which it is desired to
+travel.
+
+[Illustration: The Vitton-Huber helicopter at the Paris aeronautical
+salon in 1909. It has the double concentric axis of the Leger
+helicopter and the propelling planes of the Cornu machine.]
+
+The gyropter differs from the Cornu type of helicopter in degree rather
+than in kind. In the Scotch machine, known as the Davidson gyropter,
+the propellers have the form of immense umbrellas made up of curving
+slats. The frame of the structure has the shape of a T, one of the
+gyropters being attached to each of the arms of the T. The axes upon
+which the gyropters revolve may be inclined so that their power may be
+exerted to draw the apparatus along in a horizontal direction after it
+has been raised to the desired altitude.
+
+The gyropters of the Davidson machine are 28 feet in diameter, the
+entire structure being 67 feet long, and weighing 3 tons. It has been
+calculated that with the proposed pair of 50 horse-power engines the
+gyropters will lift 5 tons. Upon a trial with a 10 horse-power motor
+connected to one of the gyropters, that end of the apparatus was lifted
+from the ground at 55 revolutions per minute--the boiler pressure being
+800 lbs. to the square inch, at which pressure it burst, wrecking the
+machine.
+
+An example of the gyroplane is the French Breguet apparatus, a blend of
+the aeroplane and the helicopter. It combines the fixed wing-planes of
+the one with the revolving vanes of the other. The revolving surfaces
+have an area of 82 square feet, and the fixed surfaces 376 square feet.
+The total weight of machine and operator is about 1,350 lbs. Fitted
+with a 40 horse-power motor, it rose freely into the air.
+
+The ornithopter, or flapping-wing type of flying machine, though the
+object of experiment and research for years, must still be regarded as
+unsuccessful. The apparatus of M. de la Hault may be taken as typical
+of the best effort in that line, and it is yet in the experimental
+stage. The throbbing beat of the mechanism, in imitation of the bird’s
+wings, has always proved disastrous to the structure before sufficient
+power was developed to lift the apparatus.
+
+The most prominent exponent of the tetrahedral type--that made up of
+numbers of small cells set one upon another--is the _Cygnet_ of Dr.
+Alexander Graham Bell, which perhaps is more a kite than a true flying
+machine. The first _Cygnet_ had 3,000 cells, and lifted its pilot to a
+height of 176 feet. The _Cygnet II_. has 5,000 tetrahedral cells, and
+is propelled by a 50 horse-power motor. It has yet to make its record.
+
+One of the most recently devised machines is that known as the Fritz
+Russ flyer. It has two wings, each in the form of half a cylinder, the
+convex curve upward. It is driven by two immense helical screws, or
+spirals, set within the semi-cylinders. No details of its performances
+are obtainable.
+
+
+
+
+Chapter VIII.
+
+FLYING MACHINES: HOW TO OPERATE.
+
+    Instinctive balance--When the motor skips--Progressive
+    experience--Plum Island School methods--Lilienthal’s
+    conclusions--The Curtiss mechanism and controls--Speed
+    records--Cross-country flying--Landing--Essential
+    qualifications--Ground practice--Future relief.
+
+
+Any one who has learned to ride a bicycle will recall the great
+difficulty at first experienced to preserve equilibrium. But once the
+knack was gained, how simple the matter seemed! Balancing became a
+second nature, which came into play instinctively, without conscious
+thought or effort. On smooth roads it was not even necessary to grasp
+the handle-bars. The swaying of the body was sufficient to guide the
+machine in the desired direction.
+
+Much of this experience is paralleled by that of the would-be aviator.
+First, he must acquire the art of balancing himself and his machine in
+the air without conscious effort. Unfortunately, this is even harder
+than in the case of the bicycle. The cases would be more nearly alike
+if the road beneath and ahead of the bicyclist were heaving and falling
+as in an earthquake, with no light to guide him; for the air currents
+on which the aviator must ride are in constant and irregular motion,
+and are as wholly invisible to him as would be the road at night to the
+rider of the wheel.
+
+And there are other things to distract the attention of the pilot of an
+aeroplane--notably the roar of the propeller, and the rush of wind in
+his face, comparable only to the ceaseless and breath-taking force of
+the hurricane.
+
+The well-known aviator, Charles K. Hamilton, says:--“So far as the air
+currents are concerned, I rely entirely on instinctive action; but my
+ear is always on the alert. The danger signal of the aviator is when
+he hears his motor miss an explosion. Then he knows that trouble is
+in store. Sometimes he can speed up his engine, just as an automobile
+driver does, and get it to renew its normal action. But if he fails
+in this, and the motor stops, he must dip his deflecting planes, and
+try to negotiate a landing in open country. Sometimes there is no
+preliminary warning from the motor that it is going to cease working.
+That is the time when the aviator must be prepared to act quickly.
+Unless the deflecting planes are manipulated instantly, aviator and
+aeroplane will rapidly land a tangled mass on the ground.”
+
+[Illustration: Result of a failure to deflect the planes quickly enough
+when the engine stopped. The operator fortunately escaped with but a
+few bruises.]
+
+At the same time, Mr. Hamilton says: “Driving an aeroplane at a speed
+of 120 miles an hour is not nearly so difficult a task as driving an
+automobile 60 miles an hour. In running an automobile at high speed
+the driver must be on the job every second. Nothing but untiring
+vigilance can protect him from danger. There are turns in the road, bad
+stretches of pavement, and other like difficulties, and he can never
+tell at what moment he is to encounter some vehicle, perhaps travelling
+in the opposite direction. But with an aeroplane it is a different
+proposition. Once a man becomes accustomed to aeroplaning, it is a
+matter of unconscious attention.... He has no obstacles to encounter
+except cross-currents of air. Air and wind are much quicker than a man
+can think and put his thought into action. Unless experience has taught
+the aviator to maintain his equilibrium instinctively, he is sure to
+come to grief.”
+
+The Wright brothers spent years in learning the art of balancing in
+the air before they appeared in public as aviators. And their method
+of teaching pupils is evidence that they believe the only road to
+successful aviation is through progressive experience, leading up from
+the use of gliders for short flights to the actual machines with motors
+only after one has become an instinctive equilibrist.
+
+At the Plum Island school of the Herring-Burgess Company the learner is
+compelled to begin at the beginning and work the thing out for himself.
+He is placed in a glider which rests on the ground. The glider is
+locked down by a catch which may be released by pulling a string. To
+the front end of the glider is attached a long elastic which may be
+stretched more or less, according to the pull desired. The beginner
+starts with the elastic stretched but a little. When all is ready he
+pulls the catch free, and is thrown forward for a few feet. As practice
+gains for him better control, he makes a longer flight; and when he
+can show a perfect mastery of his craft for a flight of 300 feet, and
+not till then, he is permitted to begin practice with a motor-driven
+machine.
+
+[Illustration: A French apparatus for instructing pupils in aviation.]
+
+The lamented Otto Lilienthal, whose experience in more than 2,000
+flights gives his instructions unquestionable weight, urges that the
+“gradual development of flight should begin with the simplest apparatus
+and movements, and without the complication of dynamic means. With
+simple wing surfaces ... man can carry out limited flights ... by
+gliding through the air from elevated points in paths more or less
+descending. The peculiarities of wind effects can best be learned by
+such exercises.... The maintenance of equilibrium in forward flight
+is a matter of practice, and can be learned only by repeated personal
+experiment.... Actual practice in individual flight presents the best
+prospects for developing our capacity until it leads to perfected free
+flight.”
+
+The essential importance of thorough preparation in the school of
+experience could scarcely be made plainer or stronger. If it seems that
+undue emphasis has been laid upon this point, the explanation must be
+found in the deplorable death record among aviators from accidents in
+the air. With few exceptions, the cause of accident has been reported
+as, “The aviator seemed to lose control of his machine.” If this is
+the case with professional flyers, the need for thorough preliminary
+training cannot be too strongly insisted upon.
+
+Having attained the art of balancing, the aviator has to learn
+the mechanism by which he may control his machine. While all of
+the principal machines are but different embodiments of the same
+principles, there is a diversity of design in the arrangement of the
+means of control. We shall describe that of the Curtiss biplane, as
+largely typical of them all.
+
+In general, the biplane consists of two large sustaining planes, one
+above the other. Between the planes is the motor which operates a
+propeller located in the rear of the planes. Projecting behind the
+planes, and held by a framework of bamboo rods, is a small horizontal
+plane, called the tail. The rudder which guides the aeroplane to the
+right or the left is partially bisected by the tail. This rudder is
+worked by wires which run to a steering wheel located in front of
+the pilot’s seat. This wheel is similar in size and appearance to
+the steering wheel of an automobile, and is used in the same way for
+guiding the aeroplane to the right or left. (See illustration of the
+Curtiss machine in Chapter V.)
+
+In front of the planes, supported on a shorter projecting framework,
+is the altitude rudder, a pair of planes hinged horizontally, so that
+their front edges may tip up or down. When they tilt up, the air
+through which the machine is passing catches on the under sides and
+lifts them up, thus elevating the front of the whole aeroplane and
+causing it to glide upward. The opposite action takes place when these
+altitude planes are tilted downward. This altitude rudder is controlled
+by a long rod which runs to the steering wheel. By pushing on the wheel
+the rod is shoved forward and turns the altitude planes upward. Pulling
+the wheel turns the rudder planes downward. This rod has a backward and
+forward thrust of over two feet, but the usual movement in ordinary
+wind currents is rarely more than an inch. In climbing to high levels
+or swooping down rapidly the extreme play of the rod is about four or
+five inches.
+
+Thus the steering wheel controls both the horizontal and vertical
+movements of the aeroplane. More than this, it is a feeler to the
+aviator, warning him of the condition of the air currents, and for
+this reason must not be grasped too firmly. It is to be held steady,
+yet loosely enough to transmit any wavering force in the air to the
+sensitive touch of the pilot, enabling him instinctively to rise or dip
+as the current compels.
+
+[Illustration: _Courtesy N. Y. Times._
+
+    View of the centre of the new Wright machine, showing method of
+    operating. Archibald Hoxsey in the pilot’s seat. In his right
+    hand he holds a lever with two handles, one operating the warping
+    of the wing tips, and the other the rudder. Both handles may be
+    grasped at once, operating both rudder and wing tips at the same
+    moment. In his left hand Hoxsey grasps the lever operating the
+    elevating plane--at the rear in this type. The passenger’s seat
+    is shown at the pilot’s right.]
+
+The preserving of an even keel is accomplished in the Curtiss machine
+by small planes hinged between the main planes at the outer ends.
+They serve to prevent the machine from tipping over sideways. They
+are operated by arms, projecting from the back of the aviator’s seat,
+which embrace his shoulders on each side, and are moved by the swaying
+of his body. In a measure, they are automatic in action, for when the
+aeroplane sags downward on one side, the pilot naturally leans the
+other way to preserve his balance, and that motion swings the ailerons
+(as these small stabilizing planes are called) in such a way that the
+pressure of the wind restores the aeroplane to an even keel. The wires
+which connect them with the back of the seat are so arranged that when
+one aileron is being pulled down at its rear edge the rear of the
+other one is being raised, thus doubling the effect. As the machine is
+righted the aviator comes back to an upright position, and the ailerons
+become level once more.
+
+[Illustration: Starting a Wright machine. When the word is given both
+assistants pull vigorously downward on the propeller blades.]
+
+There are other controls which the pilot must operate consciously.
+In the Curtiss machine these are levers moved by the feet. With a
+pressure of the right foot he short-circuits the magneto, thus cutting
+off the spark in the engine cylinders and stopping the motor. This
+lever also puts a brake on the forward landing wheels, and checks the
+speed of the machine as it touches the ground. The right foot also
+controls the pump which forces the lubricating oil faster or slower to
+the points where it is needed.
+
+The left foot operates the lever which controls the throttle by which
+the aviator can regulate the flow of gas to the engine cylinders. The
+average speed of the 7-foot propeller is 1,100 revolutions per minute.
+With the throttle it may be cut down to 100 revolutions per minute,
+which is not fast enough to keep afloat, but will help along when
+gliding.
+
+Obviously, travelling with the wind enables the aviator to make his
+best speed records, for the speed of the wind is added to that of his
+machine through the air. Again, since the wind is always slower near
+the ground, the aviator making a speed record will climb up to a level
+where the surface currents no longer affect his machine. But over hilly
+and wooded country the air is often flowing or rushing in conflicting
+channels, and the aviator does not know what he may be called upon to
+face from one moment to the next. If the aeroplane starts to drop, it
+is only necessary to push the steering wheel forward a little--perhaps
+half an inch--to bring it up again. Usually, the machine will drop
+on an even keel. Then, in addition to the motion just described, the
+aviator will lean toward the higher side, thus moving the ailerons by
+the seat-back, and at the same time he will turn the steering wheel
+toward the lower side. This movement of the seat-back is rarely more
+than 2 inches.
+
+[Illustration:
+
+    Diagram showing action of wind on flight of aeroplane. The force
+    and direction of the wind being represented by the line _A B_,
+    and the propelling force and steered direction being _A C_, the
+    actual path travelled will be _A D_.]
+
+In flying across country a sharp lookout is kept on the land below. If
+it be of a character unfit for landing, as woods, or thickly settled
+towns, the aviator must keep high up in the air, lest his engine stop
+and he be compelled to glide to the earth. A machine will glide forward
+3 feet for each foot that it drops, if skilfully handled. If he is up
+200 feet, he will have to find a landing ground within 600 feet. If
+he is up 500 feet, he may choose his alighting ground anywhere within
+1,500 feet. Over a city like New York, a less altitude than 1,500 feet
+would hardly be safe, if a glide became necessary.
+
+Mr. Clifford B. Harmon, who was an aeronaut of distinction before he
+became an aviator, under the instruction of Paulhan, has this to say:
+“It is like riding a bicycle, or running an automobile. You have to try
+it alone to really learn how. When one first handles a flying machine
+it is advisable to keep on the ground, just rolling along. This is a
+harder mental trial than you will imagine. As soon as one is seated in
+a flying machine he wishes to fly. It is almost impossible to submit to
+staying near the earth. But until the manipulation of the levers and
+the steering gear has become second nature, this must be done. It is
+best to go very slow in the beginning. Skipping along the ground will
+teach a driver much. When one first gets up in the air it is necessary
+to keep far from all obstacles, like buildings, trees, or crowds. There
+is the same tendency to run into them that an amateur bicycle rider
+has in regard to stones and ruts on the ground. When he keeps his eye
+on them and tries with all his might to steer clear of them, he runs
+right into them.”
+
+[Illustration: Practicing with a monoplane, 20 feet above the ground.]
+
+When asked what he regarded the fundamental requirements in an aviator,
+Mr. Harmon said: “First, he must be muscularly strong; so that he
+will not tire. Second, he should have a thorough understanding of the
+mechanism of the machine he drives. Third, mental poise--the ability to
+think quick and to act instantly upon your thought. Fourth, a feeling
+of confidence in the air, so that he will not feel strange or out of
+place. This familiarity with the air can be best obtained by first
+being a passenger in a balloon, then by controlling one alone, and
+lastly going up in a flying machine.”
+
+[Illustration: Grahame-White on his Bleriot No. XII. The lever in front
+of him operates all the controls through the movement of the drum at
+its base.]
+
+Mr. Claude Grahame-White, the noted English aviator, has this to say of
+his first experience with his big “No. XII.” Bleriot monoplane--which
+differs in many important features from the “No. XI.” machine in which
+M. Bleriot crossed the English Channel: “After several disappointments,
+I eventually obtained the delivery of my machine in working order....
+As I had gathered a good deal of information from watching the antics
+and profiting by the errors made by other beginners on Bleriot
+monoplanes, I had a good idea of what _not_ to do when the engine
+was started up and we were ready for our first trial.... It was a
+cold morning, but the engine started up at the first quarter turn.
+After many warnings from M. Bleriot’s foreman not on any account to
+accelerate my engine too much, I mounted the machine along with my
+friend as passenger, and immediately gave the word to let go, and we
+were soon speeding along the ground at a good sixty kilometers (about
+37 miles) per hour.... Being very anxious to see whether the machine
+would lift off the ground, I gave a slight jerk to the elevating
+plane, and soon felt the machine rise into the air; but remembering
+the warnings of the foreman, and being anxious not to risk breaking
+the machine, I closed the throttle and contented myself with running
+around on the ground to familiarize myself with the handling of the
+machine.... The next day we got down to Issy about five o’clock in
+the morning, some two hours before the Bleriot mechanics turned up.
+However, we got the machine out, and tied it to some railings, and then
+I had my first experience of starting an engine, which to a novice
+at first sight appears a most hazardous undertaking; for unless the
+machine is either firmly held by several men, or is strongly tied up,
+it has a tendency to immediately leap forward. We successfully started
+the engine, and then rigged up a leash, and when we had mounted the
+machine, we let go; and before eight o’clock we had accomplished
+several very successful flights, both with and against the wind. These
+experiences we continued throughout the day, and by nightfall I felt
+quite capable of an extended flight, if only the ground had been large
+enough.... The following day M. Bleriot returned, and he sent for me
+and strongly urged me not to use the aeroplane any more at Issy, as he
+said the ground was far too small for such a powerful machine.”
+
+[Illustration:
+
+    Diagram of Bleriot monoplane, showing controlling lever _L_
+    and bell-shaped drum _C_, to which all controlling wires are
+    attached. When the bell is rocked back and forward the elevator
+    tips on the rear plane are moved; rocking from side to side moves
+    the stabilizing tips of the main plane. Turning the bell around
+    moves the rudder.]
+
+[Illustration:
+
+    The Marmonier gyroscopic pendulum, devised to secure automatic
+    stability of aeroplanes. The wheels are driven by the aeroplane
+    motor at high speed. The pendulum rod is extended upward above
+    the axis and carries a vane which is engaged by any gust of wind
+    from either side of the aeroplane, tending to tilt the pendulum,
+    and bringing its gyroscopic resistance into play to warp the
+    wings, or operate ailerons.]
+
+The caution shown by these experienced aviators cannot be too closely
+followed by a novice. These men do not say that their assiduous
+practice on the ground was the fruit of timidity. On the contrary,
+although they are long past the preliminary stages, their advice to
+beginners is uniformly in the line of caution and thorough practice.
+
+[Illustration:
+
+    When the aeroplane is steered to the left, the pendulum swings to
+    the right and depresses the right side of the plane, as in (_c_).
+    The reaction of the air raises the right side of the plane until
+    both surfaces are perpendicular to the inclined pendulum, as in
+    (_d_).
+
+Diagrams showing action of Marmonier gyroscopic pendulum.]
+
+Even after one has become an expert, the battle is not won, by any
+means. While flying in calm weather is extremely pleasurable, a
+protracted flight is very fatiguing; and when it is necessary to
+wrestle with gusts of high wind and fickle air currents, the strain
+upon the strongest nerve is a serious source of danger in that the
+aviator is liable to be suddenly overcome by weariness when he most
+needs to be on the alert.
+
+[Illustration:
+
+    In that inclined position the aeroplane makes the turn, and
+    when the course again becomes straight, both the gyroscopic and
+    centrifugal forces cease, and the pendulum under the influence
+    of gravity becomes vertical. In this position it is inclined to
+    the left with respect to the planes, on which its effect is to
+    depress the left wing and so right the aeroplane, as in (_e_).
+
+Diagram showing action of Marmonier gyroscopic pendulum.]
+
+Engine troubles are much fewer than they used to be, and a more
+dependable form of motor relieves the mind of the aviator from such
+mental disturbance. Some device in the line of a wind-shield would be
+a real boon, for even in the best weather there is the ceaseless rush
+of air into one’s face at 45 to 50 miles an hour. The endurance of this
+for hours is of itself a tax upon the most vigorous physique.
+
+With the passing of the present spectacular stage of the art of flying
+there will doubtless come a more reliable form of machine, with
+corresponding relief to the operator. Automatic mechanism will supplant
+the intense and continual mental attention now demanded; and as this
+demand decreases, the joys of flying will be considerably enhanced.
+
+[Illustration:
+
+    If, when pursuing a straight course, the aeroplane is tilted by
+    a sideways wind (_b_), the action of the pendulum as described
+    above restores it to an even keel, as in (_a_).
+
+Diagrams showing action of Marmonier gyroscopic pendulum.]
+
+
+
+
+Chapter IX.
+
+FLYING MACHINES: HOW TO BUILD.
+
+    Santos-Dumont’s gift--_La Demoiselle_--Mechanical skill
+    required--Preparatory practice--General dimensions--The
+    frame--The motor--The main planes--The rudder-tail--The
+    propeller--Shaping the blades--Maxim’s experience--The running
+    gear--The controls--Scrupulous workmanship.
+
+
+When Santos-Dumont in 1909 gave to the world the unrestricted
+privilege of building monoplanes after the plans of his famous No.
+20--afterward named _La Demoiselle_--he gave not only the best he knew,
+but as much as any one knows about the building of flying machines.
+Santos-Dumont has chosen the monoplane for himself because his long
+experience commends it above others, and _La Demoiselle_ was the
+crowning achievement of years spent in the construction and operation
+of airships of all types. In view of Santos-Dumont’s notable successes
+in his chosen field of activity, no one will go astray in following his
+advice.
+
+Of course, the possession of plans and specifications for an aeroplane
+does not make any man a skilled mechanic. It is well to understand at
+the start that a certain degree of mechanical ability is required in
+building a machine which will be entirely safe. Nor does the possession
+of a successful machine make one an aeronaut. As in the case of
+bicycling, there is no substitute for actual experience, while in the
+airship the art of balancing is of even greater importance than on the
+bicycle.
+
+The would-be aviator is therefore advised to put himself through a
+course of training of mind and body.
+
+Intelligent experimenting with some one of the models described in
+Chapter XI. will teach much of the action of aeroplanes in calms
+and when winds are blowing; and practice with an easily constructed
+glider (see Chapter XII.) will give experience in balancing which
+will be of the greatest value when one launches into the air for the
+first time with a power-driven machine. An expert acquaintance with
+gasoline motors and magnetos is a prime necessity. In short, every bit
+of information on the subject of flying machines and their operation
+cannot fail to be useful in some degree.
+
+The dimensions of the various parts of the Santos-Dumont monoplane are
+given on the original plans according to the metric system. In reducing
+these to “long measure” inches, all measurements have been given to the
+nearest eighth of an inch.
+
+In general, we may note some of the peculiarities of _La Demoiselle_.
+The spread of the plane is 18 feet from tip to tip, and it is 20 feet
+over all from bow to stern. In height, it is about 4 feet 2 inches when
+the propeller blades are in a horizontal position. The total weight
+of the machine is 265 lbs., of which the engine weighs about 66 lbs.
+The area of the plane is 115 square feet, so that the total weight
+supported by each square foot with Santos-Dumont (weighing 110 lbs.) on
+board is a trifle over 3 lbs.
+
+The frame of the body of the monoplane is largely of bamboo, the three
+main poles being 2 inches in diameter at the front, and tapering to
+about 1 inch at the rear. They are jointed with brass sockets just back
+of the plane, for convenience of taking apart for transportation. Two
+of these poles extend from the axle of the wheels backward and slightly
+upward to the rudder-post. The third extends from the middle of the
+plane between the wings, backward and downward to the rudder-post.
+In cross-section the three form a triangle with the apex at the top.
+These bamboo poles are braced about every 2 feet with struts of steel
+tubing of oval section, and the panels so formed are tied by diagonals
+of piano wire fitted with turn-buckles to draw them taut.
+
+[Illustration:
+
+    Side view of the Santos-Dumont monoplane. _MP_, main plane with
+    radiator, _R_, hung underneath; _RP_, rudder plane worked by
+    wires _HC_, attached to lever _L_; _VC_, vertical control wires;
+    _WT_, tube through which run the warping wires worked by lever
+    _K_, in a pocket of the pilot’s coat; _B_, _B_, bamboo poles of
+    frame; _S_, _S_, brass, or aluminum sockets; _D_, _D_, struts
+    of bicycle tubing; _G_, gasoline; _RG_, reserve gasoline; _M_,
+    motor; _P_, propeller; _Q_, _Q_, outer rib of plane, showing
+    camber; _N_, skid.]
+
+In the Santos-Dumont machine a 2-cylinder, opposed Darracq motor of
+30 horse-power was used. It is of the water-cooled type, the cooling
+radiator being a gridiron of very thin ⅛-inch copper tubing, and hung
+up on the under side of the plane on either side of the engine. The
+cylinders have a bore of about 4⅛ inches, and a stroke of about 4¾
+inches. The propeller is 2-bladed, 6½ feet across, and is run at 1,400
+revolutions per minute, at which speed it exerts a pull of 242 lbs.
+
+Each wing of the main plane is built upon 2 transverse spars extending
+outward from the upper bamboo pole, starting at a slight angle upward
+and bending downward nearly to the horizontal as they approach the
+outer extremities. These spars are of ash, 2 inches wide, and tapering
+in thickness from 1⅛ inches at the central bamboo to about ⅞ inch at
+the tips of the wings. They are bent into shape by immersion in hot
+water, and straining them around blocks nailed to the floor of the
+workshop, in the form shown at QQ, p. 177.
+
+[Illustration:
+
+    Front view of the Santos-Dumont monoplane, showing position
+    of tubular struts supporting the engine and the wings; also
+    the guys, and warping wires entering the tubes inside the
+    wheels. _MP_, the main plane; _TP_, tail plane in the rear;
+    _R_, radiators; _M_, motor; _P_, propeller, the arrow showing
+    direction of revolution.]
+
+The front spar is set about 9 inches back from the front edge of the
+plane, and the rear one about 12 inches forward of the back edge of
+the plane. Across these spars, and beneath them, running fore and aft,
+are bamboo rods about ¾ of an inch in diameter at the forward end,
+and tapering toward the rear. They are set 8½ inches apart (centre
+to centre), except at the tips of the wings. The two outer panels
+are 10¼ inches from centre to centre of the rods, to give greater
+elasticity in warping. These fore-and-aft rods are 6 feet 5 inches
+long, except directly back of the propeller, where they are 5 feet 8
+inches long; they are bound to the spars with brass wire No. 25, at the
+intersections. They also are bent to a curved form, as shown in the
+plans, by the aid of the hot-water bath. Diagonal guys of piano wire
+are used to truss the frame in two panels in each wing.
+
+Around the outer free ends of the rods runs a piano wire No. 20, which
+is let into the tips of the rods in a slot ⅜ inch deep. To prevent
+the splitting of the bamboo, a turn or two of the brass wire may be
+made around the rod just back of the slot; but it is much better to
+provide thin brass caps for the ends of the rods, and to cut the slots
+in the metal as well as in the rods. Instead of caps, ferrules will do.
+When the slots are cut, let the tongue formed in the cutting be bent
+down across the bamboo to form the floor to the slot, upon which the
+piano wire may rest. The difference in weight and cost is very little,
+and the damage that may result from a split rod may be serious.
+
+[Illustration: Plan and details of construction of _La Demoiselle_.]
+
+After the frame of the plane is completed it is to be covered with
+cloth on both sides, so as entirely to enclose the frame, except only
+the tips of the rods, as shown in the plans. In the Santos-Dumont
+monoplane the cloth used is of closely woven silk, but a strong,
+unbleached muslin will do--the kind made especially for aeroplanes is
+best.
+
+Both upper and lower surfaces must be stretched taut, the edges front
+and back being turned over the piano wire, and the wire hemmed in.
+The upper and lower surfaces are then sewed together--“through and
+through,” as a seamstress would say--along both sides of each rod, so
+that the rods are practically in “pockets.” Nothing must be slighted,
+if safety in flying is to be assured.
+
+[Illustration: Sectional diagram of 2-cylinder Darracq opposed motor.]
+
+[Illustration: Diagram of 4-cylinder Darracq opposed motor.]
+
+[Illustration: Diagram of 3-cylinder Anzani motor.
+
+Motors suitable for _La Demoiselle_ monoplane.]
+
+The tail of the monoplane is a rigid combination of two planes
+intersecting each other at right angles along a central bamboo pole
+which extends back 3 feet 5½ inches from the rudder-post, to which it
+is attached by a double joint, permitting it to move upon either the
+vertical or the horizontal axis.
+
+Although this tail, or rudder, may seem at first glance somewhat
+complicated in the plans, it will not be found so if the frame of the
+upright or vertical plane be first constructed, and that of the level
+or horizontal plane afterward built fast to it at right angles.
+
+As with the main plane, the tail is to be covered on both sides with
+cloth, the vertical part first; the horizontal halves on either side so
+covered that the cloth of the latter may be sewed above and below the
+central pole. All of the ribs in the tail are to be stitched in with
+“pockets,” as directed for the rods of the main plane.
+
+The construction of the motor is possible to an expert machinist only,
+and the aeroplane builder will save time and money by buying his engine
+from a reliable maker. It is not necessary to send to France for a
+Darracq motor. Any good gasoline engine of equal power, and about the
+same weight, will serve the purpose.
+
+The making of the propeller is practicable for a careful workman. The
+illustrations will give a better idea than words of how it should be
+done. It should be remembered, however, that the safety of the aviator
+depends as much upon the propeller as upon any other part of the
+machine. The splitting of the blades when in motion has been the cause
+of serious accidents. The utmost care, therefore, should be exercised
+in the selection of the wood, and in the glueing of the several
+sections into one solid mass, allowing the work to dry thoroughly under
+heavy pressure.
+
+[Illustration:
+
+    Diagram showing how the layers of wood are placed for glueing:
+    _A_, at the hub; _B_, half way to the tip of the blade; _C_, at
+    the tip. The dotted lines show the form of the blade at these
+    points.]
+
+The forming of the blades requires a good deal of skill, and some
+careful preliminary study. It is apparent that the speed of a point
+at the tip of a revolving blade is much greater than that of a point
+near the hub, for it traverses a larger circle in the same period of
+time. But if the propeller is to do effective work without unequal
+strain, the twist in the blade must be such that each point in the
+length of the blade is exerting an equal pull on the air. It is
+necessary, therefore, that the slower-moving part of the blade, near
+the hub, or axis, shall cut “deeper” into the air than the more swiftly
+moving tip of the blade. Consequently the blade becomes continually
+“flatter” (approaching the plane in which it revolves) as we work
+from the hub outward toward the tip. This “flattening” is well shown
+in the nearly finished blade clamped to the bench at the right of the
+illustration--which shows a four-bladed propeller, instead of the
+two-bladed type needed for the monoplane.
+
+The propeller used for propulsion in air differs from the
+propeller-wheel used for ships in water, in that the blades are curved
+laterally; the forward face of the blade being convex, and the rearward
+face concave. The object of this shaping is the same as for curving the
+surface of the plane--to secure smoother entry into the air forward,
+and a compression in the rear which adds to the holding power on
+the substance of the air. It is extremely difficult to describe this
+complex shape, and the amateur builder of a propeller will do well to
+inspect one made by a professional, or to buy it ready made with his
+engine.
+
+[Illustration: Forming a 4-blade propeller out of 8 layers of wood
+glued firmly together.]
+
+The following quotation from Sir Hiram Maxim’s account of his most
+effective propeller may aid the ambitious aeroplane builder: “My large
+screws were made with a great degree of accuracy; they were perfectly
+smooth and even on both sides, the blades being thin and held in
+position by a strip of rigid wood on the back of the blade.... Like
+the small screws, they were made of the very best kind of seasoned
+American white pine, and when finished were varnished on both sides
+with hot glue. When this was thoroughly dry, they were sand-papered
+again, and made perfectly smooth and even. The blades were then covered
+with strong Irish linen fabric of the smoothest and best make. Glue
+was used for attaching the fabric, and when dry another coat of glue
+was applied, the surface rubbed down again, and then painted with
+zinc white in the ordinary way and varnished. These screws worked
+exceedingly well.”
+
+The covering of the blades with linen glued fast commends itself to the
+careful workman as affording precaution against the splintering of the
+blades when in rapid motion. Some propellers have their wooden blades
+encased with thin sheet aluminum to accomplish the same purpose, but
+for the amateur builder linen is far easier to apply.
+
+[Illustration:
+
+    This method of mounting the wheels of the chassis has been found
+    the most satisfactory. The spring takes up the shock of a sudden
+    landing and the pivot working in the hollow post allows the
+    entire mounting to swing like a caster, and adapt itself to any
+    direction at which the machine may strike the ground.]
+
+The wheels are of the bicycle type, with wire spokes, but with hubs six
+inches long. The axle is bent to incline upward at the ends, so that
+the wheels incline outward at the ground, the better to take the shock
+of a sideways thrust when landing. The usual metal or wood rims may be
+used, but special tires of exceptionally light construction, made for
+aeroplanes, should be purchased.
+
+The controlling wires or cords for moving the rudder (or tail) and for
+warping the tips of the wings are of flexible wire cable, such as is
+made for use as steering rope on small boats. The cable controlling
+the horizontal plane of the rudder-tail is fastened to a lever at the
+right hand of the operator. The cable governing the vertical plane
+of the rudder-tail is attached to a wheel at the left hand of the
+operator. The cables which warp the tips of the wings are fastened to
+a lever which projects upward just back of the operator’s seat, and
+which is slipped into a long pocket sewed to the back of his coat, so
+that the swaying of his body in response to the fling of the tipping
+machine tends to restore it to an even keel. Springs are attached to
+all of these controlling wires, strong enough to bring them back to a
+normal position when the operator removes his hands from the steering
+apparatus.
+
+The brass sockets used in connecting the tubular struts to the main
+bamboos and the rudder-post, and in fastening the axle of the wheels to
+the lower bamboos and elsewhere, should be thoroughly made and brazed
+by a good mechanic, for no one should risk the chance of a faulty
+joint at a critical spot, when an accident may mean the loss of life.
+
+[Illustration: Diagram of Bleriot monoplane showing sizes of parts, in
+metres. Reduced to feet and inches these measurements are:
+
+  0.60 metres      1 ft. 11½    in.
+  1.50 metres      4 ft. 11     in.
+  2.10 metres      6 ft. 10½    in.
+  3.50 metres     11 ft.  6     in.
+  8.00 metres     26 ft.  3     in.
+  8.60 metres     28 ft.  2½    in.
+
+    The diagram being drawn to scale other dimensions may be found.
+    In both the plan (upper figure) and elevation (lower figure),
+    _A_, _A_, is the main plane; _B_, tail plane; _C_, body; _D_,
+    elevator wing-tips; _E_, rudder; _a_, _a_, rigid spar; _b_, _b_,
+    flexible spar; _r_, _r_, points of attachment for warping-wires;
+    _h_, _h_, guys; _H_, propeller; _M_, motor; _R_, radiator; _S_,
+    pilot’s seat; _P_, chassis.]
+
+For the rest, it has seemed better to put the details of construction
+on the plans themselves, where they will be available to the aeroplane
+builder without the trouble of continually consulting the text.
+
+Some of the work on an aeroplane will be found simple and easy; some of
+it, difficult and requiring much patience; and some impracticable to
+any one but a trained mechanic. But in all of it, the worker’s motto
+should be, “Fidelity in every detail.”
+
+
+
+
+Chapter X.
+
+FLYING MACHINES: MOTORS.
+
+    Early use of steam--Reliability necessary--The gasoline
+    motor--Carburetion--Compression--Ignition--Air-cooling--Water-cooling--Lubrication--The
+    magneto--Weight--Types of motors--The propeller--Form, size, and
+    pitch--Slip--Materials--Construction.
+
+
+The possibility of the existence of the flying machine as we have it
+to-day has been ascribed to the invention of the gasoline motor. While
+this is not to be denied, it is also true that the gasoline motors
+designed and built for automobiles and motor-boats have had to be
+wellnigh revolutionized to make them suitable for use in the various
+forms of aircraft. And it is to be remembered, doubtless to their
+greater credit, that Henson, Hargrave, Langley, and Maxim had all
+succeeded in adapting steam to the problem of the flight of models, the
+two latter using gasoline to produce the steam.
+
+Perhaps the one predominant qualification demanded of the aeroplane
+motor is reliability. A motor-car or motor-boat can be stopped, and
+engine troubles attended to with comparatively little inconvenience.
+The aeroplane simply cannot stop without peril. It is possible for
+a skilful pilot to reach the earth when his engine stops, if he is
+fortunately high enough to have space for the downward glide which will
+gain for him the necessary headway for steering. At a lesser height he
+is sure to crash to the earth.
+
+An understanding of the principles on which the gasoline motor works
+is essential to a fair estimate of the comparative advantages of the
+different types used to propel aeroplanes. In the first place, the
+radical difference between the gasoline motor and other engines is the
+method of using the fuel. It is not burned in ordinary fashion, but the
+gasoline is first vaporized and mixed with a certain proportion of air,
+in a contrivance called a carburetor. This gaseous mixture is pumped
+into the cylinder of the motor by the action of the motor itself,
+compressed into about one-tenth of its normal volume, and then exploded
+by a strong electric spark at just the right moment to have its force
+act most advantageously to drive the machinery onward.
+
+[Illustration: The “Fiat” 8-cylinder air-cooled motor, of the “V” type,
+made in France.]
+
+It is apparent that there are several chances for failure in this
+series. The carburetor may not do its part accurately. The mixture of
+air and vapor may not be in such proportions that it will explode; in
+that case, the power from that stroke will be missing, and the engine
+will falter and slow down. Or a leakage in the cylinder may prevent
+the proper compression of the mixture, the force from the explosion
+will be greatly reduced, with a corresponding loss of power and speed.
+Or the electric spark may not be “fat” enough--that is, of sufficient
+volume and heat to fire the mixture; or it may not “spark” at just
+the right moment; if too soon, it will exert its force against the
+onward motion: if too late, it will not deliver the full power of the
+explosion at the time when its force is most useful. The necessity for
+absolute perfection in these operations is obvious.
+
+[Illustration: A near view of the Holmes engine from the driving side.]
+
+[Illustration: The Holmes rotative engine, 7-cylinder 35 horse-power,
+weighing 160 pounds.
+
+An American engine built in Chicago, Ill.]
+
+Other peculiarities of the gasoline motor affect considerably its
+use for aeroplanes. The continual and oft-repeated explosions of the
+gaseous mixture inside of the cylinder generate great heat, and this
+not only interferes with its regularity of movement, but within a
+very brief time checks it altogether. To keep the cylinder cool enough
+to be serviceable, two methods are in use: the air-cooling system and
+the water-cooling system. In the first, flanges of very thin metal
+are cast on the outside of the cylinder wall. These flanges take up
+the intense heat, and being spread out over a large surface in this
+way, the rushing of the air through them as the machine flies (or
+sometimes blown through them with a rotary fan) cools them to some
+degree. With the water-cooling system, the cylinder has an external
+jacket, the space between being filled with water which is made to
+circulate constantly by a small pump. In its course the water which
+has just taken up the heat from the cylinder travels through a radiator
+in which it is spread out very thin, and this radiator is so placed
+in the machine that it receives the full draught from the air rushing
+through the machine as it flies. The amount of water required for
+cooling a motor is about 1⅕ lbs. per horse-power. With an 8-cylinder 50
+horse-power motor, this water would add the very considerable item of
+60 lbs. to the weight the machine has to carry. As noted in a previous
+chapter, the McCurdy biplane has its radiator formed into a sustaining
+plane, and supports its own weight when travelling in the air.
+
+[Illustration: The 180 horse-power engine of Sir Hiram Maxim; of the
+“opposed” type, compound, and driven by steam.]
+
+[Illustration:
+
+    The Anzani motor and propeller which carried M. Bleriot across
+    the English Channel. The curved edge of the propeller blades is
+    the entering edge, the propeller turning from the right of the
+    picture over to the left. The Anzani is of the “radiant” type and
+    is of French build.]
+
+It is an unsettled point with manufacturers whether the greater
+efficiency (generally acknowledged) of the water-cooled engine more
+than compensates for the extra weight of the water.
+
+Another feature peculiar to the gasoline motor is the necessity for
+such continual oiling that it is styled “lubrication,” and various
+devices have been invented to do the work automatically, without
+attention from the pilot further than the watching of his oil-gauge to
+see that a full flow of oil is being pumped through the oiling system.
+
+The electric current which produces the spark inside of the cylinder
+is supplied by a magneto, a machine formed of permanent magnets of
+horseshoe form, between the poles of which a magnetized armature is
+made to revolve rapidly by the machinery which turns the propeller.
+This magneto is often connected with a small storage battery, or
+accumulator, which stores up a certain amount of current for use when
+starting, or in case the magneto gives out.
+
+[Illustration: Sectional drawings showing details of construction of
+the Anzani motor. The flanges of the air-cooling system are distinctly
+shown. The section at the left is from the side; that at the right,
+from the front. All measurements are in millimètres. A millimètre is
+0.039 inch.]
+
+The great rivalry of the builders of motors has been in cutting down
+the weight per horse-power to the lowest possible figure. It goes
+without saying that useless weight is a disadvantage in an aeroplane,
+but it has not been proven that the very lightest engines have made a
+better showing than those of sturdier build.
+
+[Illustration: The “Gobron” engine of the “double opposed,” or
+cross-shaped type. A water-cooled engine, with 8 cylinders.]
+
+One of the items in the weight of an engine has been the fly-wheel
+found necessary on all motors of 4 cylinders or less to give steadiness
+to the running. With a larger number of cylinders, and a consequently
+larger number of impulses in the circuit of the propeller, the
+vibration is so reduced that the fly-wheel has been dispensed with.
+
+[Illustration: The Emerson 6-cylinder aviation engine, of the “tandem”
+type, water-cooled; 60 horse-power; made at Alexandria, Va.]
+
+There are several distinct types of aircraft engines, based on the
+arrangement of the cylinders. The “tandem” type has the cylinders
+standing upright in a row, one behind another. There may be as many as
+eight in a row. The Curtiss and Wright engines are examples. Another
+type is the “opposed” arrangement, the cylinders being placed in a
+horizontal position and in two sets, one working opposite the other.
+An example of this type is seen in the Darracq motor used on the
+Santos-Dumont monoplane. Another type is the “V” arrangement, the
+cylinders set alternately leaning to right and to left, as seen in
+the “Fiat” engine. Still another type is the “radiant,” in which the
+cylinders are all above the horizontal, and disposed like rays from
+the rising sun. The 3-cylinder Anzani engine and the 5- and 7-cylinder
+R-E-P engines are examples. The “star” type is exemplified in the 5
+and 7-cylinder engines in which the cylinders radiate at equal angles
+all around the circle. The “double opposed” or cross-shaped type is
+shown in the “Gobron” engine. In all of these types the cylinders are
+stationary, and turn the propeller shaft either by cranks or by gearing.
+
+[Illustration: The Elbridge engine, of the “tandem” type and
+water-cooled. It is an American engine, built at Rochester, N. Y.]
+
+An entirely distinct type of engine, and one which has been devised
+solely for the aeroplane, is the rotative--often miscalled the rotary,
+which is totally different. The rotative type may be illustrated by the
+Gnome motor. In this engine the seven cylinders turn around the shaft,
+which is stationary. The propeller is fastened to the cylinders, and
+revolves with them. This ingenious effect is produced by an offset
+of the crank-shaft of half the stroke of the pistons, whose rods are
+all connected with the crank-shaft. The entire system revolves around
+the main shaft as a centre, the crank-shaft being also stationary.
+
+[Illustration:
+
+    The famous Gnome motor; 50 horse-power, 7-cylinder, air-cooled;
+    of the rotative type; made in France. This illustration shows the
+    Gnome steel propeller.]
+
+[Illustration: Sectional diagram of the 5-cylinder R-E-P motor; of the
+“radiant” type.]
+
+[Illustration: Sectional diagram of the 5-cylinder Bayard-Clement
+motor; of the “star” type.]
+
+Strictly speaking, the propeller is not a part of the motor of the
+flying machine, but it is so intimately connected with it in the
+utilization of the power created by the motor, that it will be treated
+of briefly in this chapter.
+
+The form of the air-propeller has passed through a long and varied
+development, starting with that of the marine propeller, which was
+found to be very inefficient in so loose a medium as air. On account
+of this lack of density in the air, it was found necessary to act on
+large masses of it at practically the same time to gain the thrust
+needed to propel the aeroplane swiftly, and this led to increasing the
+diameter of the propeller to secure action on a proportionally larger
+area of air. The principle involved is simply the geometric rule that
+the areas of circles are to each other as the squares of their radii.
+Thus the surface of air acted on by two propellers, one of 6 feet
+diameter and the other of 8 feet diameter, would be in the proportion
+of 9 to 16; and as the central part of a propeller has practically no
+thrust effect, the efficiency of the 8-foot propeller is nearly twice
+that of the 6-foot propeller--other factors being equal. But these
+other factors may be made to vary widely. For instance, the number of
+revolutions may be increased for the smaller propeller, thus engaging
+more air than the larger one at a lower speed; and, in practice, it is
+possible to run a small propeller at a speed that would not be safe for
+a large one. Another factor is the pitch of the propeller, which may
+be described as the distance the hub of the propeller would advance in
+one complete revolution if the blades moved in an unyielding medium,
+as a section of the thread of an ordinary bolt moves in its nut. In
+the yielding mass of the air the propeller advances only a part of its
+pitch, in some cases not more than half. The difference between the
+theoretical advance and the actual advance is called the “slip.”
+
+[Illustration:
+
+    The Call Aviation Engine, of the opposed type; water-cooled. The
+    cylinders are large and few in number. The 100 horse-power engine
+    has but 4 cylinders, and weighs only 250 pounds. (The Gnome 100
+    horse-power engine has 14 cylinders.) This is an American engine,
+    built at Girard, Kansas.]
+
+In practical work the number of blades which have been found to be most
+effective is two. More blades than two seem to so disturb the air that
+there is no hold for the propeller. In the case of slowly revolving
+propellers, as in most airship mechanisms, four-bladed propellers are
+used with good effect. But where the diameter of the propeller is
+about 8 feet, and the number of revolutions about 1,200 per minute, the
+two-bladed type is used almost exclusively.
+
+The many differing forms of the blades of the propeller is evidence
+that the manufacturers have not decided upon any definite shape as
+being the best. Some have straight edges nearly or quite parallel;
+others have the entering edge straight and the rear edge curved; in
+others the entering edge is curved, and the rear edge straight; or
+both edges may be curved. The majority of the wooden propellers are
+of the third-mentioned type, and the curve is fashioned so that at
+each section of its length the blade presents the same area of surface
+in the same time. Hence the outer tip, travelling the fastest, is
+narrower than the middle of the blade, and it is also much thinner to
+lessen the centrifugal force acting upon it at great speeds. Near the
+hub, however, where the travel is slowest, the constructional problem
+demands that the blade contract in width and be made stout. In fact, it
+becomes almost round in section.
+
+Many propellers are made of metal, with tubular shanks and blades of
+sheet metal, the latter either solid sheets or formed with a double
+surface and hollow inside. Still others have a frame of metal with
+blades of fabric put on loosely, so that it may adapt itself to the
+pressure of the air in revolving. That great strength is requisite
+becomes plain when it is considered that the speed of the tip of
+a propeller blade often reaches seven miles a minute! And at this
+velocity the centrifugal force excited--tending to tear the blades to
+splinters--is prodigious.
+
+Just as the curved surface of the planes of an aeroplane is more
+effective than a flat surface in compressing the air beneath them,
+and thus securing a firmer medium on which to glide, so the propeller
+blades are curved laterally (across their width) to compress the air
+behind them and thus secure a better hold. The advancing side of the
+blade is formed with a still greater curve, to gain the advantage due
+to the unexplained lift of the paradox aeroplane.
+
+Where the propeller is built of wood it is made of several layers,
+usually of different kinds of wood, with the grain running in slightly
+different directions, and all carefully glued together into a solid
+block. Ash, spruce, and mahogany, in alternating layers, are a favorite
+combination. In some instances the wooden propeller is sheathed in
+sheet aluminum; in others, it is well coated with glue which is
+sandpapered down very smooth, then varnished, and then polished to the
+highest lustre--to reduce the effect of the viscosity of the air to the
+minimum.
+
+[Illustration:
+
+    Two propellers, the one on the left of left-hand pitch; the
+    other of right-hand pitch. Both are thrusting propellers, and
+    are viewed from the rear. These fine models are of the laminated
+    type, and are of American make; the one to the left a Paragon
+    propeller made in Washington, D. C.; the other a Brauner
+    propeller made in New York.]
+
+In order to get the best results, the propeller and the motor must be
+suited to each other. Some motors which “race” with a propeller which
+is slightly too small, work admirably with one a little heavier, or
+with a longer diameter.
+
+The question as to whether one propeller, or two, is the better
+practice, has not been decided. The majority of aeroplanes have but
+one. The Wright and the Cody machines have two. The certainty of
+serious consequences to a machine having two, should one of them be
+disabled, or even broken so as to reduce the area, seems to favor the
+use of but one.
+
+
+
+
+Chapter XI.
+
+MODEL FLYING MACHINES.
+
+    Awakened popular interest--The workshop’s share--Needed
+    devices--Super-sensitive inventions--Unsolved problems--Tools
+    and materials--A model biplane--The propeller--The body--The
+    steering plane--The main planes--Assembling the parts--The
+    motive power--Flying the model--A monoplane model--Carving a
+    propeller--Many ideas illustrated--Clubs and competitions--Some
+    remarkable records.
+
+
+It is related of Benjamin Franklin that when he went out with his
+famous kite with the wire string, trying to collect electricity from
+the thundercloud, he took a boy along to forestall the ridicule that he
+knew would be meted out to him if he openly flew the kite himself.
+
+Other scientific experimenters, notably those working upon the problem
+of human flight in our own time, have encountered a similar condition
+of the public mind, and have chosen to conduct their trials in secret
+rather than to contend with the derision, criticism, and loss of
+reputation which a sceptical world would have been quick to heap upon
+them.
+
+But such a complete revolution of thought has been experienced in these
+latter days that groups of notable scientific men gravely flying kites,
+or experimenting with carefully made models of flying machines, arouse
+only the deepest interest, and their smallest discoveries are eagerly
+seized upon by the daily press as news of the first importance.
+
+So much remains to be learned in the field of aeronautics that no
+builder and flyer of the little model aeroplanes can fail to gain
+valuable information, if that is his intention. On the other hand, if
+it be the sport of racing these model aeroplanes which appeals to him,
+the instruction given in the pages following will be equally useful.
+
+The earnest student of aviation is reminded that the progressive work
+in this new art of flying is not being done altogether, nor even in
+large part, by the daring operators who, with superb courage, are
+performing such remarkable feats with the flying machines of the
+present moment. Not one of them would claim that his machine is all
+that could be desired. On the contrary, these intrepid men more than
+any others are fully aware of the many and serious defects of the
+apparatus they use for lack of better. The scientific student in his
+workshop, patiently experimenting with his models, and working to
+prove or disprove untested theories, is doubtless doing an invaluable
+part in bringing about the sort of flying which will be more truly
+profitable to humanity in general, though less spectacular.
+
+[Illustration: A model flying machine built and flown by Louis Paulhan,
+the noted aviator, at a prize contest for models in France. The design
+is after Langley’s model, with tandem monoplane surfaces placed at a
+dihedral angle.]
+
+One of the greatest needs of the present machines is an automatic
+balancer which shall supersede the concentrated attention which the
+operator is now compelled to exercise in order to keep his machine
+right side up. The discovery of the principle upon which such a
+balancer must be built is undoubtedly within the reach of the builder
+and flyer of models. It has been asserted by an eminent scientific
+experimenter in things aeronautic that “we cannot hope to make a
+sensitive apparatus quick enough to take advantage of the rising
+currents of the air,” etc. With due respect to the publicly expressed
+opinion of this investigator, it is well to reassure ourselves against
+so pessimistic an outlook by remembering that the construction of just
+such supersensitive apparatus is a task to which man has frequently
+applied his intellectual powers with signal success. Witness the
+photomicroscope, which records faithfully an enlarged view of
+objects too minute to be even visible to the human eye; the aneroid
+barometer, so sensitive that it will indicate the difference in level
+between the table and the floor; the thermostat, which regulates the
+temperature of the water flowing in the domestic heating system with a
+delicacy impossible to the most highly constituted human organism; the
+seismograph, detecting, recording, and almost locating earth tremors
+originating thousands of miles away; the automatic fire sprinkler;
+the safety-valve; the recording thermometer and other meteorological
+instruments; and last, if not of least importance, the common
+alarm-clock. And these are but a few of the contrivances with which
+man does by blind mechanism that which is impossible to his sentient
+determination.
+
+Even if the nervous system could be schooled into endurance of the
+wear and tear of consciously balancing an aeroplane for many hours, it
+is still imperative that the task be not left to the exertion of human
+wits, but controlled by self-acting devices responding instantly to
+unforeseen conditions as they occur.
+
+[Illustration: Diagram showing turbulent air currents produced when a
+flat plane is forced through the air at a large angle of incidence in
+the direction A-B.]
+
+[Illustration: Diagram showing smoothly flowing air currents caused by
+correctly shaped plane at proper angle of incidence.]
+
+Some of the problems of which the model-builder may find the solution
+are: whether large screws revolving slowly, or small screws revolving
+rapidly, are the more effective; how many blades a propeller should
+have, and their most effective shape; what is the “perfect” material
+for the planes (Maxim found that with a smooth wooden plane he could
+lift 2½ times the weight that could be lifted with the best made
+fabric-covered plane); whether the centre of gravity of the aeroplane
+should be above or below the centre of lift, or should coincide with
+it; new formulas for the correct expression of the lift in terms of the
+velocity, and angle of inclination--the former formulas having been
+proved erroneous by actual experience; how to take the best advantage
+of the “tangential force” announced by Lilienthal, and reasserted by
+Hargrave; and many others. And there is always the “paradox aeroplane”
+to be explained--and when explained it will be no longer a paradox, but
+will doubtless open the way to the most surprising advance in the art
+of flying.
+
+It is not assumed that every reader of this chapter will become a
+studious experimenter, but it is unquestionably true that every
+model-builder, in his effort to produce winning machines, will be more
+than likely to discover some fact of value in the progress making
+toward the ultimate establishment of the commercial navigation of the
+air.
+
+The tools and materials requisite for the building of model aeroplanes
+are few and inexpensive. For the tools--a small hammer; a small iron
+“block” plane; a fine-cut half-round file; a pair of round-nose pliers;
+three twist drills (as used for drilling metals), the largest 1/16 inch
+diameter, and two smaller sizes, with an adjustable brad-awl handle
+to hold them; a sharp pocket knife; and, if practicable, a small hand
+vise. The vise may be dispensed with, and common brad-awls may take the
+place of the drills, if necessary.
+
+For the first-described model--the simplest--the following materials
+are needed: some thin whitewood, 1/16 inch thick (as prepared for
+fret-sawing); some spruce sticks, ¼ inch square (sky-rocket sticks are
+good); a sheet of heavy glazed paper; a bottle of liquid glue; some of
+the smallest (in diameter) brass screws, ¼ to ½ inch long; some brass
+wire, 1/20 inch in diameter; 100 inches of square rubber (elastic)
+“cord,” such as is used on return-balls, but 1/16 inch square; and a
+few strips of draughtsman’s tracing cloth.
+
+[Illustration:
+
+    _A_, _B_, blank from which propeller is shaped; _P_, _P_, pencil
+    lines at centre of bend; _C_, _D_, sections of blade at points
+    opposite; _E_, _G_, propeller after twisting; _H_, view of
+    propeller endwise, showing outward twist of tips; also shaft.]
+
+As the propeller is the most difficult part to make, it is best
+to begin with it. The flat blank is cut out of the whitewood, and
+subjected to the action of steam issuing from the spout of an actively
+boiling tea-kettle. The steam must be hot; mere vapor will not do the
+work. When the strip has become pliable, the shaping is done by slowly
+bending and twisting at the same time--perhaps “coaxing” would be the
+better word, for it must be done gently and with patience--and the
+steam must be playing on the wood all the time, first on one side of
+the strip, then on the other, at the point where the fibres are being
+bent. The utmost care should be taken to have the two blades bent
+exactly alike--although, of course, with a contrary twist, the one to
+the right and the other to the left, on each side of the centre. A
+lead-pencil line across each blade at exactly the same distance from
+the centre will serve to fix accurately the centre of the bend. If
+two blocks are made with slots cut at the angle of 1 inch rise to 2¼
+inches base, and nailed to the top of the work bench just far enough
+apart to allow the tips of the screw to be slid into the slots, the
+drying in perfect shape will be facilitated. The centre may be held to
+a true upright by two other blocks, one on each side of the centre.
+Some strips of whitewood may be so rigid that the steam will not make
+them sufficiently supple. In this case it may be necessary to dip them
+bodily into the boiling water, or even to leave them immersed for a few
+minutes; afterward bending them in the hot steam. But a wetted stick
+requires longer to dry and set in the screw shape. When the propeller
+is thoroughly dry and set in proper form, it should be worked into the
+finished shape with the half-round file, according to the several
+sections shown beside the elevation for each part of the blade. The
+two strengthening piece’s are then to be glued on at the centre of the
+screw, and when thoroughly dry, worked down smoothly to shape. When
+all is dry and hard it should be smoothed with the finest emery cloth
+and given a coat of shellac varnish, which, in turn, may be rubbed to
+a polish with rotten stone and oil.
+
+It may be remarked, in passing, that this is a crude method of making a
+propeller, and the result cannot be very good. It is given here because
+it is the easiest way, and the propeller will work. A much better way
+is described further on--and the better the propeller, the better any
+model will fly. But for a novice, no time will be lost in making this
+one, for the experience gained will enable the model-builder to do
+better work with the second one than he could do without it.
+
+For the aeroplane body we get out a straight spar of spruce, ¼ inch
+square and 15½ inches long. At the front end of this--on the upper
+side--is to be glued a small triangular piece of wood to serve as a
+support for the forward or steering plane, tilting it up at the front
+edge at the angle represented by a rise of 1 in 8. This block should
+be shaped on its upper side to fit the curve of the under side of the
+steering-plane, which will be screwed to it.
+
+The steering-plane is cut according to plan, out of 1/16 inch
+whitewood, planed down gradually to be at the ends about half that
+thickness. This plane is to be steamed and bent to a curve (fore and
+aft) as shown in the sectional view. The steam should play on the
+_convex_ side of the bend while it is being shaped. To hold it in
+proper form until it is set, blocks with curved slots may be used, or
+it may be bound with thread to a moulding block of equal length formed
+to the proper curve. When thoroughly dry it is to be smoothed with the
+emery cloth, and a strip of tracing cloth--glossy face out--is to be
+glued across each end, to prevent breaking in case of a fall. It is
+then to be varnished with shellac, and polished, as directed for the
+propeller. Indeed, it should be said once for all that every part of
+the model should be as glossy as it is possible to make it without
+adding to the weight, and that all “entering edges” (those which push
+into and divide the air when in flight) should be as sharp as is
+practicable with the material used.
+
+The steering-plane is to be fastened in place by a single screw long
+enough to pierce the plane and the supporting block, and enter the
+spar. The hole for this screw (as for all screws used) should be
+drilled carefully, to avoid the least splitting of the wood, and just
+large enough to have the screw “bite” without forcing its way in. This
+screw which holds the plane is to be screwed “home” but not too tight,
+so that in case the flying model should strike upon it in falling,
+the slender plane will swivel, and not break. It will be noticed that
+while this screw passes through the centre of the plane sideways, it is
+nearer to the forward edge than to the rear edge.
+
+If the work has been accurate, the plane will balance if the spar
+is supported--upon the finger, perhaps, as that is sensitive to any
+tendency to tipping. If either wing is too heavy, restore the balance
+by filing a little from the tip of that wing.
+
+The main planes are next to be made. The lower deck of the biplane is
+of the 1/16 inch whitewood, and the upper one is of the glazed paper
+upon a skeleton framework of wood. The upright walls are of paper.
+The wooden deck is to be bent into the proper curve with the aid of
+steam, and when dry and set in form is to be finished and polished. The
+frame for the upper deck is made of the thin whitewood, and is held
+to its position by two diagonal struts of whitewood bent at the ends
+with steam, and two straight upright struts or posts. It is better to
+bend all cross-pieces into the curve of the plane with steam, but they
+may be worked into the curve on the top side with plane and file, and
+left flat on the lower side. The drawings show full details of the
+construction, drawn accurately to scale.
+
+It is best to glue all joints, and in addition to insert tiny screws,
+where shown in the plans, at the time of gluing.
+
+When all the wooden parts are in place the entire outline of the upper
+plane and the upright walls is to be formed of silk thread carried
+from point to point, and tied upon very small pins (such as are used
+in rolls of ribbon at the stores) inserted in the wood. The glazed
+paper is put on double, glossy side out. Cut the pieces twice as large
+(and a trifle more) than is needed, and fold so that the smooth crease
+comes to the front and the cut edges come together at the rear. The two
+inner walls should be put in place first, so as to enclose the thread
+front and back, and the post, between the two leaves of the folded
+paper. Cutting the paper half an inch too long will give one fourth of
+an inch to turn flat top and bottom to fasten to the upper and lower
+decks respectively. The two outer walls and the upper deck may be cut
+all in one piece, the under leaf being slit to pass on either side of
+the inner walls. A bit of glue here and there will steady the parts to
+their places. The cut edges at the rear of the deck and walls should
+be caught together with a thin film of glue, so as to enclose the rear
+threads.
+
+[Illustration:
+
+    _A_, _B_, plan, and _C_, section, of steering plane; _H_, section
+    of lower main plane; _L_, wood skeleton of upper plane; _T_,
+    _T_, silk thread; _O_, _O_, posts; _J_, _J_, braces; _E_, rubber
+    strands; _D_, forward hook; _G_, shaft; _F_, thrust-block; _K_,
+    upper plane of paper; _M_, elevation of main planes, from the
+    rear.]
+
+When the biplane is completed it is to be fastened securely to the spar
+in such a position that it is accurately balanced--from side to side.
+The spar may be laid on a table, and the biplane placed across it in
+its approximate position. Then move the plane to one side until it tips
+down, and mark the spot on the rear edge of the plane. Repeat this
+operation toward the other side, and the centre between the two marks
+should be accurately fastened over the centre line of the spar. Even
+with the greatest care there may still be failure to balance exactly,
+but a little work with a file on the heavy side, or a bit of chewing
+gum stuck on the lighter side, will remedy the matter.
+
+The body of the aeroplane being now built, it is in order to fit it
+with propelling mechanism. The motive power to whirl the propeller we
+have already prepared is to be the torsion, or twisting strain--in this
+case the force of untwisting--of india rubber. When several strands
+of pure rubber cord are twisted up tight, their elasticity tends to
+untwist them with considerable force. The attachment for the rubber
+strands at the front end of the spar is a sort of bracket made of the
+brass wire. The ends of the wire are turned up just a little, and they
+are set into little holes in the under side of the spar. Where the wire
+turns downward to form the hook it is bound tightly to the spar with
+silk thread. The hook-shaped tip is formed of the loop of the wire
+doubled upon itself. The rear attachment of the rubber strands is a
+loop upon the propeller shaft itself. As shown in the drawings, this
+shaft is but a piece of the brass wire. On one end (the rear) an open
+loop is formed, and into this is slipped the centre of the propeller.
+The short end of the loop is then twisted around the longer shank--very
+carefully, lest the wire cut into and destroy the propeller. Two turns
+of the wire is enough, and then the tip of the twisted end should be
+worked down flat with the file, to serve as a bearing for the propeller
+against the thrust-block. This latter is made of a piece of sheet brass
+(a bit of printers’ brass “rule” is just the thing) about 1/40 of an
+inch thick. It should be ¼ of an inch wide except at the forward end,
+where it is to be filed to a long point and bent up a trifle to enter
+the wood of the spar. The rear end is bent down (not too sharply, lest
+it break) to form the bearing for the propeller, a hole being drilled
+through it for the propeller shaft, just large enough for the shaft to
+turn freely in it. Another smaller hole is to be drilled for a little
+screw to enter the rear end of the spar. Next pass the straight end
+of the propeller shaft through the hole drilled for it, and with the
+pliers form a round hook for the rear attachment of the rubber strands.
+Screw the brass bearing into place, and for additional strength, wind
+a binding of silk thread around it and the spar.
+
+Tie the ends of the rubber cord together, divide it into ten even
+strands, and pass the loops over the two hooks--and the machine is
+ready for flight.
+
+To wind up the rubber it will be necessary to turn the propeller in
+the opposite direction to which it will move when the model is flying.
+About 100 turns will be required. After it is wound, hold the machine
+by the rear end of the spar, letting the propeller press against the
+hand so it cannot unwind. Raise it slightly above the head, holding the
+spar level, or inclined upward a little (as experience may dictate),
+and launch the model by a gentle throw forward. If the work has been
+well done it may fly from 150 to 200 feet.
+
+Many experiments may be made with this machine. If it flies too high,
+weight the front end of the spar; if too low, gliding downward from the
+start, weight the rear end. A bit of chewing gum may be enough to cause
+it to ride level and make a longer and prettier flight.
+
+A very graceful model is that of the monoplane type illustrated in
+the accompanying reproductions from photographs. The front view shows
+the little machine just ready to take flight from a table. The view
+from the rear is a snap-shot taken while it was actually flying. This
+successful model was made by Harold S. Lynn, of Stamford, Conn. Before
+discussing the details of construction, let us notice some peculiar
+features shown by the photographs. The forward plane is arched; that
+is, the tips of the plane bend slightly downward from the centre. On
+the contrary, the two wings of the rear plane bend slightly upward from
+the centre, making a dihedral angle, as it is called; that is, an angle
+between two surfaces, as distinguished from an angle between two lines.
+The toy wheels, Mr. Lynn says, are put on principally for “looks” but
+they are also useful in permitting a start to be made from a table or
+even from the floor, instead of the usual way of holding the model in
+the hands and giving it a slight throw to get it started. However, the
+wheels add to the weight, and the model will not fly quite so far with
+them as without.
+
+[Illustration: Front view of the Lynn model of the monoplane type,
+about to take flight.]
+
+The wood from which this model was made was taken from a bamboo
+fish-pole, such as may be bought anywhere for a dime. The pole was
+split up, and the suitable pieces whittled and planed down to the
+proper sizes, as given in the plans. In putting the framework of the
+planes together, it is well to notch very slightly each rib and spar
+where they cross. Touch the joint with a bit of liquid glue, and wind
+quickly with a few turns of sewing silk and tie tightly. This must be
+done with delicacy, or the frames will be out of true. If the work is
+done rapidly the glue will not set until all the ties on the plane are
+finished. Another way is to touch the joinings with a drop of glue,
+place the ribs in position on the spars, and lay a board carefully on
+the work, leaving it there until all is dry, when the tying can be
+done. It either case the joinings should be touched again with the
+liquid glue and allowed to dry hard.
+
+[Illustration: The Lynn model monoplane in flight, from below and from
+the rear.]
+
+The best material for covering these frames is the thinnest of China
+silk. If this is too expensive, use the thinnest cambric. But the model
+will not fly so far with the cambric covering. The material is cut
+one-fourth of an inch too large on every side, and folded over, and the
+fold glued down. Care should be taken that the frame is square and true
+before the covering is glued on.
+
+The motive power is produced by twisting up rubber tubing. Five and
+three-quarter feet of pure rubber tubing are required. It is tied
+together with silk so as to form a continuous ring. This is looped
+over two screw-hooks of brass, one in the rear block and the other
+constituting the shaft. This looped tubing is twisted by turning the
+propeller backward about two hundred turns. As it untwists it turns the
+propeller, which, in this model, is a “traction” screw, and pulls the
+machine after it as it advances through the air.
+
+[Illustration:
+
+    Details and plans of the Harold Lynn model monoplane. _W_, tail
+    block; _Y_, thrust-block; _S_, mounting of propeller showing
+    glass bead next the thrust-block, and one leather washer outside
+    the screw; _B_, glass bead; _C_, tin washer; _M_, _M_, tin lugs
+    holding axle of wheels.]
+
+The propeller in this instance is formed from a piece of very thin
+tin, such as is used for the tops of cans containing condensed milk.
+Reference to the many illustrations throughout this book showing
+propellers of flying machines will give one a very good idea of the
+proper way to bend the blades. The mounting with the glass bead and the
+two leather washers is shown in detail in the plans.
+
+[Illustration:
+
+    Method of forming propeller of the laminated, or layer, type. The
+    layers of wood are glued,in the position shown and the blades
+    carved out according to the sections. Only one blade is shown
+    from the axle to the tip. This will make a right hand propeller.
+   ]
+
+The wheels are taken from a toy wagon, and a pair of tin ears will
+serve as bearings for the axle.
+
+The sport of flying model aeroplanes has led to the formation of many
+clubs in this country as well as in Europe. Some of the mechanisms that
+have been devised, and some of the contrivances to make the models
+fly better and further, are illustrated in the drawings.
+
+[Illustration:
+
+    At _A_ is shown a method of mounting the propeller with a glass
+    or china bead to reduce friction, and a brass corner to aid
+    in strengthening. _B_ shows a transmission of power by two
+    spur wheels and chain. _C_ is a device for using two rubber
+    twists acting on the two spur wheels _S_, _S_, which in turn
+    are connected with the propeller with a chain drive. _D_ shows
+    a launching apparatus for starting. _W_, the model; _V_, the
+    carriage; _F_, the trigger guard; _T_, trigger; _E_, elastic cord
+    for throwing the carriage forward to the stop _K_.]
+
+Records have been made which seem marvellous when it is considered
+that 200 feet is a very good flight for a model propelled by rubber.
+For instance, at the contest of the Birmingham Aero Club (England) in
+September, one of the contestants won the prize with a flight of 447
+feet, lasting 48 seconds. The next best records for duration of flight
+were 39 seconds and 38 seconds. A model aeroplane which is “guaranteed
+to fly 1,000 feet,” according to the advertisement in an English
+magazine, is offered for sale at $15.
+
+The American record for length of flight is held by Mr. Frank Schober,
+of New York, with a distance of 215 feet 6 inches. His model was of the
+Langley type of tandem monoplane, and very highly finished. The problem
+is largely one of adequate power without serious increase of weight.
+
+
+
+
+Chapter XII.
+
+THE GLIDER.
+
+    Aerial balancing--Practice necessary--Simplicity of the glider
+    Materials--Construction--Gliding--Feats with the Montgomery
+    glider--Noted experimenters--Glider clubs.
+
+
+It is a matter of record that the Wright brothers spent the better part
+of three years among the sand dunes of the North Carolina sea-coast
+practising with gliders. In this way they acquired that confidence
+while in the air which comes from intimate acquaintance with its
+peculiarities, and which cannot be gained in any other way. It is true
+that the Wrights were then developing not only themselves, but also
+their gliders; but the latter work was done once for all. To develop
+aviators, however, means the repeating of the same process for each
+individual--just as each for himself must be taught to read. And the
+glider is the “First Reader” in aeronautics.
+
+The long trail of wrecks of costly aeroplanes marking the progress in
+the art of flying marks also the lack of preparatory training, which
+their owners either thought unnecessary, or hoped to escape by some
+royal road less wearisome than persistent personal practice. But they
+all paid dearly to discover that there is no royal road. Practice, more
+practice, and still more practice--that is the secret of successful
+aeroplane flight.
+
+For this purpose the glider is much superior to the power-driven
+aeroplane. There are no controls to learn, no mechanism to manipulate.
+One simply launches into the air, and concentrates his efforts upon
+balancing himself and the apparatus; not as two distinct bodies,
+however, but as a united whole. When practice has made perfect the
+ability to balance the glider instinctively, nine-tenths of the art of
+flying an aeroplane has been achieved. Not only this, but a new sport
+has been laid under contribution; one beside which coasting upon a
+snow-clad hillside is a crude form of enjoyment.
+
+Fortunately for the multitude, a glider is easily made, and its cost is
+even less than that of a bicycle. A modest degree of skill with a few
+carpenter’s tools, and a little “gumption” about odd jobs in general,
+is all that is required of the glider builder.
+
+[Illustration: A gliding slope with starting platform, erected for club
+use.]
+
+The frame of the glider is of wood, and spruce is recommended, as it
+is stronger and tougher for its weight than other woods. It should be
+of straight grain and free from knots; and as there is considerable
+difference in the weight of spruce from different trees, it is well
+to go over the pile in the lumber yard and pick out the lightest
+boards. Have them planed down smooth on both sides, and to the required
+thickness, at the mill--it will save much toilsome hand work. The
+separate parts may also be sawed out at the mill, if one desires to
+avoid this labor.
+
+The lumber needed is as follows:
+
+   4 spars          20 ft. long,     1¼ in. wide,   ¾ in. thick.
+  12 struts          3 ft. long,     1¼ in. wide,   ¾ in. thick.
+   2 rudder bars     8 ft. long,      ¾ in. wide,   ½ in. thick.
+  12 posts           4 ft. long,     1½ in. wide,   ½ in. thick.
+  41 ribs            4 ft. long,      ½ in. wide,   ½ in. thick.
+   2 arm rests       4 ft. long,      2 in. wide,   1 in. thick.
+  For rudder frame. 24 running ft.,   1 in. wide,   1 in. thick.
+
+If it be impossible to find clear spruce lumber 20 feet in length,
+the spars may be built up by splicing two 10-foot sticks together.
+For this purpose, the splicing stick should be as heavy as the single
+spar--1¼ inches wide, and ¾ inches thick--and at least 4 feet long, and
+be bolted fast to the spar with six ⅛ inch round-head carriage bolts
+with washers of large bearing surface (that is, a small hole to fit the
+bolt, and a large outer diameter) at both ends of the bolt, to prevent
+crushing the wood. A layer of liquid glue brushed between will help to
+make the joint firmer.
+
+[Illustration: Otto Lilienthal in his single-plane glider. The swinging
+forward of his feet tends to turn the glider toward the ground, and
+increase its speed.]
+
+Wherever a bolt is put in, a hole should be bored for it with a bit of
+such size that the bolt will fit snug in the hole without straining the
+grain of the wood.
+
+The corners of the finished spar are to be rounded off on a large
+curvature.
+
+The ends of the struts are to be cut down on a slight slant of about
+1/16 inch in the 1¼ inches that it laps under the spar--with the idea
+of tipping the top of the spar forward so that the ribs will spring
+naturally from it into the proper curve.
+
+The ribs should be bent by steaming, and allowed to dry and set in
+a form, or between blocks nailed upon the floor to the line of the
+correct curve. They are then nailed to the frames, the front end first:
+21 to the frame of the upper plane, and 20 to that of the lower plane,
+omitting one at the centre, where the arm pieces will be placed.
+
+Some builders tack the ribs lightly into place with small brads, and
+screw clamps formed from sheet brass or aluminum over them. Others
+use copper nails and clinch them over washers on the under side. Both
+methods are shown in the plans, but the clamps are recommended as
+giving greater stiffness, an essential feature.
+
+At the front edge of the frames the ribs are fastened flush, and being
+4 feet long and the frame but 3 feet wide, they project over the rear
+about 1 foot.
+
+The arm pieces are bolted to the spars of the lower frame 6½ inches
+on each side of the centre, so as to allow a free space of 13 inches
+between them. This opening may be made wider to accommodate a stouter
+person.
+
+[Illustration: Plan and details of Glider. The upper plane has a rib at
+the centre instead of the two arm pieces.]
+
+The posts are then put into place and bolted to the struts and the
+spars, as shown, with ⅛inch bolts.
+
+The entire structure is then to be braced diagonally with No. 16 piano
+wire. The greatest care must be taken to have these diagonals pull just
+taut, so that they shall not warp the lines of the frames out of true.
+A crooked frame will not fly straight, and is a source of danger when
+making a landing.
+
+The frames are now to be covered. There is a special balloon cloth
+made which is best for the purpose, but if that cannot be procured,
+strong cambric muslin will answer. Thirty yards of goods 1 yard wide
+will be required for the planes and the rudder. From the piece cut off
+7 lengths for each plane, 4 feet 6 inches long. These are to be sewed
+together, selvage to selvage, so as to make a sheet about 19 feet 6
+inches long and 4 feet 6 inches wide. As this is to be tacked to the
+frame, the edges must be double-hemmed to make them strong enough to
+resist tearing out at the tacks. Half an inch is first folded down
+all around; the fold is then turned back on the goods 2½ inches and
+sewed. This hem is then folded back 1 inch upon itself, and again
+stitched. Strips 3 inches wide and a little over 4 feet long are
+folded “three-double” into a width of 1 inch, and sewed along both
+edges to the large sheet exactly over where the ribs come. These are to
+strengthen the fabric where the ribs press against it. Sixteen-ounce
+tacks are used, being driven through a felt washer the size of a gun
+wad at intervals of four inches. If felt is not readily obtainable,
+common felt gun wads will do. The tacking is best begun at the middle
+of the frame, having folded the cloth there to get the centre. Then
+stretch smoothly out to the four corners and tack at each. It may
+then be necessary to loosen the two centre tacks and place them over
+again, to get rid of wrinkles. The next tacks to drive are at the ends
+of the struts; then half-way between; and so on until all are in, and
+the sheet is taut and smooth. For a finer finish, brass round-head
+upholsterer’s nails may be used.
+
+The rudder, so-called, is rather a tail, for it is not movable and does
+not steer the glider. It does steady the machine, however, and is very
+important in preserving the equilibrium when in flight. It is formed of
+two small planes intersecting each other at right angles and covered
+on both sides with the cloth, the sections covering the vertical part
+being cut along the centre and hemmed on to the upper and lower faces
+of the horizontal part. The frame for the vertical part is fastened to
+the two rudder bars which stretch out toward the rear, one from the
+upper plane, and the other from the lower. The whole construction is
+steadied by guys of the piano wire.
+
+[Illustration: Lilienthal in his double-deck glider. It proved
+unmanageable and fell, causing his death. The hill is an artificial one
+built for his own use in experimenting.]
+
+All wooden parts should be smoothed off with sandpaper, and given a
+coat of shellac varnish.
+
+To make a glide, the machine is taken to an elevated point on a
+slope, not far up to begin with. Lift the glider, get in between the
+arm rests, and raise the apparatus until the rests are snug under the
+arms. Run swiftly for a few yards and leap into the air, holding the
+front of the planes slightly elevated. If the weight of the body is
+in the right position, and the speed sufficient, the glider will take
+the air and sail with you down the slope. It may be necessary at first
+to have the help of two assistants, one at each end, to run with the
+glider for a good start.
+
+[Illustration: Diagram showing differing lines of flight as controlled
+by changing the position of the body. The wind must be blowing against
+the direction of flight; in the illustration this would be from left to
+right.]
+
+The position of the body on the arm rests can best be learned by a few
+experiments. No two gliders are quite alike in this respect, and no
+rule can be given. As to the requisite speed, it must be between 15 and
+20 miles an hour; and as this speed is impossible to a man running, it
+is gained by gliding against the wind, and thus adding the speed of the
+wind to the speed of the runner. The Wrights selected the sand dunes of
+the North Carolina coast for their glider experiments because of the
+steady winds that blow in from the ocean, across the land. These winds
+gave them the necessary speed of air upon which to sail their gliders.
+
+The first flights attempted should be short, and as experience is
+gained longer ones may be essayed.
+
+Balancing the glider from side to side is accomplished by swaying the
+lower part of the body like a pendulum, the weight to go toward the
+side which has risen. Swinging the body forward on the arm rests will
+cause the machine to dip the planes and glide more swiftly down the
+incline. Holding the weight of the body back in the arm rests will
+cause the machine to fly on a higher path and at a slower speed. This
+is objectionable because the glider is more manageable at a higher
+speed, and therefore safer. The tendency at first is to place the
+weight too far back, with a consequent loss of velocity, and with that
+a proportionate loss of control. The proper position of the body is
+slightly forward of the mechanical centre of the machine.
+
+The landing is accomplished by shoving the body backward, thus tilting
+up the front of the plane. This checks the speed, and when the feet
+touch the ground a little run, while holding back, will bring the glide
+to an end. Landing should be practised often with brief glides until
+skill is gained, for it is the most difficult operation in gliding.
+
+After one becomes expert, longer flights may be secured by going to
+higher points for the start. From an elevation of 300 feet a glide of
+1,200 feet is possible.
+
+[Illustration: Gliding with a Chanute three-decker. A start with two
+assistants.]
+
+While it is necessary to make glides against the wind, it is not wise
+to attempt flights when the wind blows harder than 10 miles an hour.
+While the flight may be successful, the landing may be disastrous.
+
+The accomplished glider operator is in line for the aeroplane, and it
+is safe to say that he will not be long without one. The skilful and
+practised operator of a glider makes the very best aeroplane pilot.
+
+This chapter would not be complete without an adequate reference to the
+gliders devised by Professor Montgomery of Santa Clara, California.
+These machines were sent up with ordinary hot-air balloons to various
+heights, reaching 4,000 feet in some instances, when they were cut
+loose and allowed to descend in a long glide, guided by their pilots.
+The time of the descent from the highest altitude was twenty minutes,
+during which the glider travelled about eight miles. The landing was
+made accurately upon a designated spot, and so gently that there was no
+perceptible jar. Two of the pilots turned completely over sideways, the
+machine righting itself after the somersault and continuing its regular
+course. Professor Montgomery has made the assertion that he can fasten
+a bag of sand weighing 150 lbs. in the driver’s seat of his glider,
+and send it up tied upside down under a balloon, and that after being
+cut loose, the machine will right itself and come safely to the ground
+without any steering.
+
+Lilienthal in Germany, Pilcher in England, and Chanute in the United
+States are names eminent in connection with the experiments with
+gliders which have been productive of discoveries of the greatest
+importance to the progress of aviation. The illustration of the Chanute
+glider shows its peculiarities plainly enough to enable any one to
+comprehend them.
+
+The establishment of glider clubs in several parts of the country has
+created a demand for ready-made machines, so that an enthusiast who
+does not wish to build his own machine may purchase it ready made.
+
+
+
+
+Chapter XIII.
+
+BALLOONS.
+
+    First air vehicle--Principle of Archimedes--Why balloons
+    rise--Inflating gases--Early history--The Montgolfiers--The
+    hot-air balloon--Charles’s hydrogen balloon--Pilatre de
+    Rozier--The first aeronaut--The first balloon voyage--Blanchard
+    and Jeffries--Crossing the English Channel--First English
+    ascensions--Notable voyages--Recent long-distance journeys
+    and high ascensions--Prize balloon races--A fascinating
+    sport--Some impressions, adventures, and hardships--Accident
+    record--Increasing interest in ballooning.
+
+
+The balloon, though the earliest and crudest means of getting up in the
+air, has not become obsolete. It has been in existence practically in
+its present general form for upwards of 500 years. Appliances have been
+added from time to time, but the big gas envelope enclosing a volume of
+some gas lighter than an equal volume of air, and the basket, or car,
+suspended below it, remain as the typical form of aerial vehicle which
+has not changed since it was first devised in times so remote as to lie
+outside the boundaries of recorded history.
+
+The common shape of the gas bag of a balloon is that of the sphere, or
+sometimes of an inverted pear. It is allowed to rise and float away in
+the air as the prevailing wind may carry it. Attempts have been made to
+steer it in a desired direction, but they did not accomplish much until
+the gas bag was made long horizontally, in proportion to its height and
+width. With a drag-rope trailing behind on the ground from the rear end
+of the gas bag, and sails on the forward end, it was possible to guide
+the elongated balloon to some extent in a determined direction.
+
+In explaining why a balloon rises in the air, it is customary to quote
+the “principle of Archimedes,” discovered and formulated by that famous
+philosopher centuries before the Christian era. Briefly stated, it is
+this: Every body immersed in a fluid is acted upon by a force pressing
+upward, which is equal to the weight of the amount of the fluid
+displaced by the immersed body.
+
+It remained for Sir Isaac Newton to explain the principle of Archimedes
+(by the discovery of the law of gravitation), and to show that the
+reason why the immersed body is apparently pushed upward, is that the
+displaced fluid is attracted downward. In the case of a submerged
+bag of a gas lighter than air, the amount of force acting on the
+surrounding air is greater than that acting on the gas, and the latter
+is simply crowded out of the way by the descending air, and forced up
+to a higher level where its lighter bulk is balanced by the gravity
+acting upon it.
+
+The fluid in which the balloon is immersed is the air. The force
+with which the air crowds down around and under the balloon is its
+weight--weight being the measure of the attraction which gravity exerts
+upon any substance.
+
+The weight of air at a temperature of 32° Fahr., at the normal
+barometer pressure at the sea-level (29.92 inches of mercury), is
+0.0807 lbs. per cubic foot. The gas used to fill a balloon must
+therefore weigh less than this, bulk for bulk, in order to be crowded
+upward by the heavier air--and thus exert its “lifting power,” as it is
+commonly called.
+
+In practice, two gases have been used for inflating balloons--hydrogen,
+and illuminating gas, made ordinarily from coal, and called “coal gas.”
+Hydrogen is the lightest substance known; that is, it is attracted less
+by gravity than any other known substance, in proportion to its bulk.
+
+[Illustration: One of the earliest attempts to steer a spherical
+balloon by retarding its speed with the drag-rope, and adjusting the
+sail to the passing wind.]
+
+A cubic foot of hydrogen weighs but 0.0056 lbs., and it will
+therefore be pushed upward in air by the difference in weight, or
+0.0751 lbs. per cubic foot. A cubic foot of coal gas weighs about
+0.0400 lbs., and is crowded upward in air with a force of 0.0407 lbs.
+
+[Illustration:
+
+    Apparatus to illustrate the principle of Archimedes. At the left,
+    the small solid glass ball and large hollow glass sphere are
+    balanced in the free air. When the balance is moved under the
+    bell-glass of the air pump (at the right), and the air exhausted,
+    the large sphere drops, showing that its previous balance was due
+    to the upward pressure of the air, greater because of its larger
+    bulk.]
+
+It is readily seen that a very large bulk of hydrogen must be used
+if any considerable weight is to be lifted. For to the weight of the
+gas must be added the weight of the containing bag, the car, and the
+network supporting it, the ballast, instruments, and passengers, and
+there must still be enough more to afford elevating power sufficient to
+raise the entire load to the desired level.
+
+Let us assume that we have a balloon with a volume of 20,000 cubic
+feet, which weighs with its appurtenances 500 pounds. The hydrogen
+it would contain would weigh about 112 pounds, and the weight of
+the air it would displace would be about 1,620 pounds. The total
+available lifting power would be about 1,000 pounds. If a long-distance
+journey is to be undertaken at a comparatively low level, this will
+be sufficient to carry the necessary ballast, and a few passengers.
+If, however, it is intended to rise to a great height, the problem
+is different. The weight of the air, and consequently its lifting
+pressure, decreases as we go upwards. If the balloon has not been
+entirely filled, the gas will expand as the pressure is reduced in the
+higher altitude. This has the effect of carrying the balloon higher.
+Heating of the contained gas by the sun will also cause a rise. On
+the other hand, the diffusion of the gas through the envelope into
+the air, and the penetration of air into the gas bag will produce a
+mixture heavier than hydrogen, and will cause the balloon to descend.
+The extreme cold of the upper air has the same effect, as it tends to
+condense to a smaller bulk the gas in the balloon. To check a descent
+the load carried by the gas must be lightened by throwing out some of
+the ballast, which is carried simply for this purpose. Finally a level
+is reached where equilibrium is established, and above which it is
+impossible to rise.
+
+The earliest recorded ascent of a balloon is credited to the Chinese,
+on the occasion of the coronation of the Emperor Fo-Kien at Pekin in
+the year 1306. If this may be called historical, it gives evidence also
+that it speedily became a lost art. The next really historic record
+belongs in the latter part of the seventeenth century, when Cyrano de
+Bergerac attempted to fly with the aid of bags of air attached to his
+person, expecting them to be so expanded by the heat of the sun as to
+rise with sufficient force to lift him. He did not succeed, but his
+idea is plainly the forerunner of the hot-air balloon.
+
+In the same century Francisco de Lana, who was clearly a man of
+much intelligence and keen reasoning ability, having determined by
+experiment that the atmosphere had weight, decided that he would be
+able to rise into the air in a ship lifted by four metal spheres 20
+feet in diameter from which the air had been exhausted. After several
+failures he abandoned his efforts upon the religious grounds that the
+Almighty doubtless did not approve such an overturning in the affairs
+of mankind as would follow the attainment of the art of flying.
+
+In 1757, Galen, a French monk, published a book, “The Art of Navigating
+in the Air,” in which he advocated filling the body of the airship
+with air secured at a great height above the sea-level, where it was
+“a thousand times lighter than water.” He showed by mathematical
+computations that the upward impulse of this air would be sufficient
+to lift a heavy load. He planned in detail a great airship to carry
+4,000,000 persons and several million packages of goods. Though it may
+have accomplished nothing more, this book is believed to have been the
+chief source of inspiration to the Montgolfiers.
+
+The discovery of hydrogen by Cavendish in 1776 gave Dr. Black the
+opportunity of suggesting that it be used to inflate a large bag and
+so lift a heavy load into the air. Although he made no attempt to
+construct such an apparatus, he afterward claimed that through this
+suggestion he was entitled to be called the real inventor of the
+balloon.
+
+This is the meagre historical record preceding the achievements of
+the brothers Stephen and Joseph Montgolfier, which marked distinctly
+the beginning of practical aeronautics. Both of these men were highly
+educated, and they were experienced workers in their father’s paper
+factory. Joseph had made some parachute drops from the roof of his
+house as early as 1771.
+
+After many experiments with steam, smoke, and hydrogen gas, with which
+they tried ineffectually to inflate large paper bags, they finally
+succeeded with heated air, and on June 5, 1783, they sent up a great
+paper hot-air balloon, 35 feet in diameter. It rose to a height of
+1,000 feet, but soon came to earth again upon cooling. It appears that
+the Montgolfiers were wholly ignorant of the fact that it was the
+rarefying of the air by heating that caused their balloon to rise, and
+they made no attempt to keep it hot while the balloon was in the air.
+
+[Illustration: An early Montgolfier balloon.]
+
+About the same time the French scientist, M. Charles, decided that
+hydrogen gas would be better than hot air to inflate balloons. Finding
+that this gas passed readily through paper, he used silk coated with a
+varnish made by dissolving rubber. His balloon was 13 feet in diameter,
+and weighed about 20 pounds. It was sent up from the Champ de Mars
+on August 29, 1783, amidst the booming of cannon, in the presence of
+300,000 spectators who assembled despite a heavy rain. It rose swiftly,
+disappearing among the clouds, and soon burst from the expansion of
+the gas in the higher and rarer atmosphere--no allowance having been
+made for this unforeseen result. It fell in a rural region near Paris,
+where it was totally destroyed by the inhabitants, who believed it to
+be some hideous form of the devil.
+
+The Montgolfiers had already come to Paris, and had constructed a
+balloon of linen and paper. Before they had opportunity of sending it
+up it was ruined by a rainstorm with a high wind. They immediately
+built another of waterproof linen which made a successful ascension on
+September 19, 1783, taking as passengers a sheep, a cock, and a duck.
+The balloon came safely to earth after being up eight minutes--falling
+in consequence of a leak in the air-bag near the top. The passengers
+were examined with great interest. The sheep and the duck seemed in
+the same excellent condition as when they went up, but the cock was
+evidently ailing. A consultation of scientists was held and it was the
+consensus of opinion that the fowl could not endure breathing the rarer
+air of the high altitude. At this juncture some one discovered that the
+cock had been trodden upon by the sheep, and the consultation closed
+abruptly.
+
+The Montgolfier brothers were loaded with honors, Stephen receiving the
+larger portion; and the people of Paris entered enthusiastically into
+the sport of making and flying small balloons of the Montgolfier type.
+
+Stephen began work at once upon a larger balloon intended to carry
+human passengers. It was fifty feet in diameter, and 85 feet high, with
+a capacity of 100,000 cubic feet. The car for the passengers was swung
+below from cords in the fashion that has since become so familiar.
+
+In the meantime Pilatre de Rozier had constructed a balloon on the
+hot-air principle, but with an arrangement to keep the air heated by a
+continuous fire in a pan under the mouth of the balloon. He made the
+first balloon ascent on record on October 15, 1783, rising to a height
+of eighty feet, in the captive balloon. On November 21, in the same
+year, de Rozier undertook an expedition in a free balloon with the
+Marquis d’Arlandes as a companion. The experiment was to have been made
+with two condemned criminals, but de Rozier and d’Arlandes succeeded in
+obtaining the King’s permission to make the attempt, and in consequence
+their names remain as those of the first aeronauts. They came safely
+to the ground after a voyage lasting twenty-five minutes. After this,
+ascensions speedily became a recognized sport, even for ladies.
+
+The greatest altitude reached by these hot-air balloons was about 9,000
+feet.
+
+[Illustration: Pilatre de Rozier’s balloon.]
+
+The great danger from fire, however, led to the closer consideration
+of the hydrogen balloon of Professor Charles, who was building one of
+30 feet diameter for the study of atmospheric phenomena. His mastery
+of the subject is shown by the fact that his balloon was equipped with
+almost every device afterward in use by the most experienced aeronauts.
+He invented the valve at the top of the bag for allowing the escape
+of gas in landing, the open neck to permit expansion, the network of
+cords to support the car, the grapnel for anchoring, and the use of a
+small pilot balloon to test the air-currents before the ascension. He
+also devised a barometer by which he was able to measure the altitude
+reached by the pressure of the atmosphere.
+
+To provide the hydrogen gas required he used the chemical method of
+pouring dilute sulphuric acid on iron filings. The process was so
+slow that it took continuous action for three days and three nights
+to secure the 14,000 cubic feet needed, but his balloon was finally
+ready on December 1, 1783. One of the brothers Robert accompanied
+Charles, and they travelled about 40 miles in a little less than 4
+hours, alighting at Nesles. Here Robert landed and Charles continued
+the voyage alone. Neglecting to take on board ballast to replace
+the weight of M. Robert, Charles was carried to a great height, and
+suffered severely from cold and the difficulty of breathing in the
+highly rarefied air. He was obliged to open his gas valve and descend
+after half an hour’s flight alone.
+
+Blanchard, another French inventor, about this time constructed a
+balloon with the intention of being the first to cross the English
+Channel in the air. He took his balloon to Dover and with Dr. Jeffries,
+an American, started on January 7, 1785. His balloon was leaky and he
+had loaded it down with a lot of useless things in the way of oars,
+provisions, and other things. All of this material and the ballast
+had to be thrown overboard at the outset, and books and parts of the
+balloon followed. Even their clothing had to be thrown over to keep the
+balloon out of the sea, and at last, when Dr. Jeffries had determined
+to jump out to enable his friend to reach the shore, an upward current
+of wind caught them and with great difficulty they landed near Calais.
+The feat was highly lauded and a monument in marble was erected on the
+spot to perpetuate the record of the achievement.
+
+De Rozier lost his life soon after in the effort to duplicate this trip
+across the Channel with his combination hydrogen and hot-air balloon.
+His idea seems to have been that he could preserve the buoyancy of
+his double balloon by heating up the air balloon at intervals.
+Unfortunately, the exuding of the hydrogen as the balloons rose formed
+an explosive mixture with the air he was rising through, and it was
+drawn to his furnace, and an explosion took place which blew the entire
+apparatus into fragments at an altitude of over 1,000 feet.
+
+[Illustration: Car and hoop of the Blanchard balloon, the first to
+cross the English Channel.]
+
+Count Zambeccari, an Italian, attempted to improve the de Rozier
+method of firing a balloon by substituting a large alcohol lamp for
+the wood fire. In the first two trial trips he fell into the sea, but
+was rescued. On the third trip his balloon was swept into a tree, and
+the overturned lamp set it on fire. To escape being burned, he threw
+himself from the balloon and was killed by the fall.
+
+The year before these feats on the Continent two notable balloon
+ascensions had taken place in England. On August 27, 1784, an aeronaut
+by the name of Tytler made the first balloon voyage within the
+boundaries of Great Britain. His balloon was of linen and varnished,
+and the record of his ascension indicates that he used hydrogen gas to
+inflate it. He soared to a great height, and descended safely.
+
+A few weeks later, the Italian aeronaut Lunardi made his first ascent
+from London. The spectacle drew the King and his councillors from their
+deliberations, and the balloon was watched until it disappeared. He
+landed in Standon, near Ware, where a stone was set to record the
+event. On October 12, he made his famous voyage from Edinburgh over the
+Firth of Forth to Ceres; a distance of 46 miles in 35 minutes, or at
+the rate of nearly 79 miles per hour; a speed rarely equalled by the
+swiftest railroad trains.
+
+From this time on balloons multiplied rapidly and the ascents were too
+numerous for recording in these pages. The few which have been selected
+for mention are notable either for the great distances traversed, or
+for the speed with which the journeys were made. It should be borne
+in mind that the fastest method of land travel in the early part of
+the period covered was by stage coach; and the sailing ship was the
+only means of crossing the water. It is no wonder that often the
+people among whom the aeronauts landed on a balloon voyage refused to
+believe the statements made as to the distance they had come, and the
+marvellously short time it had taken. And even as compared with the
+most rapid transit of the present day, the speeds attained in many
+cases have never been equalled.
+
+A remarkable English voyage was made in June, 1802, by the French
+aeronaut Garnerin and Captain Snowdon. They ascended from Chelsea
+Gardens and landed in Colchester, 60 miles distant, in 45 minutes: an
+average speed of 80 miles an hour.
+
+On December 16, 1804, Garnerin ascended from the square in front
+of Notre Dame, Paris; passing over France and into Italy, sailing
+above St. Peter’s at Rome, and the Vatican, and descending into Lake
+Bracciano--a distance of 800 miles in 20 hours. This voyage was made
+as a part of the coronation ceremonies of Napoleon I. The balloon was
+afterwards hung up in a corridor of the Vatican.
+
+On October 7, 1811, Sadler and Burcham voyaged from Birmingham to
+Boston (England), 112 miles in 1 hour 40 minutes, a speed of 67 miles
+per hour.
+
+On November 17, 1836, Charles Green and Monck Mason started on a voyage
+in the great balloon of the Vauxhall Gardens. It was pear-shaped, 60
+feet high and 50 feet in diameter, and held 85,000 cubic feet of gas.
+It was cut loose at half-past one in the afternoon, and in 3 hours had
+reached the English Channel, and in 1 hour more had crossed it, and
+was nearly over Calais. During the night it floated on over France
+in pitchy darkness and such intense cold that the oil was frozen. In
+the morning the aeronauts descended a few miles from Weilburg, in
+the Duchy of Nassau, having travelled about 500 miles in 18 hours. At
+that date, by the fastest coaches the trip would have consumed three
+days. The balloon was rechristened “The Great Balloon of Nassau” by the
+enthusiastic citizens of Weilburg.
+
+[Illustration:
+
+    Prof. T. S. C. Lowe’s mammoth balloon “City of New York,” a
+    feature of the year 1860, in which it made many short voyages in
+    the vicinity of New York and Philadelphia.]
+
+In 1849, M. Arban crossed the Alps in a balloon, starting at Marseilles
+and landing at Turin--a distance of 400 miles in 8 hours. This
+remarkable record for so long a distance at a high speed has rarely
+been equalled. It was exceeded as to distance at the same speed by the
+American aeronaut, John Wise, in 1859.
+
+One of the most famous balloons of recent times was the “Geant,” built
+by M. Nadar, in Paris, in 1853. The immense gas-bag was made of silk of
+the finest quality costing at that time about $1.30 a yard, and being
+made double, it required 22,000 yards. It had a capacity of 215,000
+cubic feet of gas, and lifted 4½ tons. The car was 13 feet square,
+and had an upper deck which was open. On its first ascent it carried
+15 passengers, including M. Nadar as captain, and the brothers Godard
+as lieutenants. A few weeks later this balloon was set free for a
+long-distance journey, and 17 hours after it left Paris it landed at
+Nieuburg in Hanover, having traversed 750 miles, a part of the time at
+the speed of fully 90 miles per hour.
+
+In July, 1859, John Wise, an American aeronaut, journeyed from St.
+Louis, Mo., to Henderson, N. Y., a distance of 950 miles in 19 hours.
+His average speed was 50 miles per hour. This record for duration at so
+high a rate of speed has never been exceeded.
+
+During the siege of Paris in 1870, seventy-three balloons were sent
+out from that city carrying mail and dispatches. These were under
+Government direction, and receive notice in a subsequent chapter
+devoted to Military Aeronautics. One of these balloons is entitled to
+mention among those famous for rapid journeys, having travelled to the
+Zuyder Zee, a distance of 285 miles, in 3 hours--an average speed of 95
+miles per hour. Another of these postal balloons belongs in the extreme
+long-distance class, having come down in Norway nearly 1,000 miles from
+Paris.
+
+In July, 1897, the Arctic explorer Andrée started on his voyage to the
+Pole. As some of his instruments have been recently recovered from
+a wandering band of Esquimaux, it is believed that a record of his
+voyage may yet be secured.
+
+In the same year a balloon under the command of Godard ascended
+at Leipsic, and after a wandering journey in an irregular course,
+descended at Wilna. The distance travelled was estimated at 1,032
+miles, but as balloon records are always based on the airline distance
+between the places of ascent and descent, this record has not been
+accepted as authoritative. The time consumed was 24¼ hours.
+
+In 1899, Captain von Sigsfield, Captain Hildebrandt, and a companion
+started from Berlin in a wind so strong that it prevented the taking
+on of an adequate load of ballast. They rose into a gale, and in two
+hours were over Breslau, having made the distance at a speed of 92
+miles per hour. In the grasp of the storm they continued their swift
+journey, landing finally high up in the snows of the Carpathian Alps in
+Austria. They were arrested by the local authorities as Russian spies,
+but succeeded in gaining their liberty by telegraphing to an official
+more closely in touch with the aeronautics of the day.
+
+In 1900 there were several balloon voyages notable for their length.
+Jacques Balsan travelled from Vincennes to Dantzig, 757 miles; Count
+de la Vaulx journeyed from Vincennes to Poland, 706 miles; Jacques
+Faure from Vincennes to Mamlity, 753 miles. In a subsequent voyage
+Jacques Balsan travelled from Vincennes to Rodom, in Russia, 843 miles,
+in 27½ hours.
+
+[Illustration: The balloon in which Coxwell and Glaisher made their
+famous ascent of 29,000 feet.]
+
+One of the longest balloon voyages on record in point of time consumed
+is that of Dr. Wegener of the Observatory at Lindenberg, in 1905. He
+remained in the air for 52¾ hours.
+
+The longest voyage, as to distance, up to 1910, was that of Count de
+La Vaulx and Count Castillon de Saint Victor in 1906, in the balloon
+“Centaur.” This was a comparatively small balloon, having a capacity
+of only 55,000 cubic feet of gas. The start was made from Vincennes on
+October 9th, and the landing at Korostischeff, in Russia, on October
+11th. The air-line distance travelled was 1,193 miles, in 35¾ hours.
+The balloon “Centaur” was afterward purchased by the Aero Club of
+America, and has made many voyages in this country.
+
+The Federation Aeronautique Internationale, an association of the
+aeronauts of all nations, was founded in 1905. One of its functions is
+an annual balloon race for the International Challenge Cup, presented
+to the association by James Gordon Bennett, to be an object for
+competition until won three times by some one competing national club.
+
+The first contest took place in September, 1906, and was won by the
+American competitor, Lieut. Frank P. Lahm, with a voyage of 402 miles.
+
+The second contest was from St. Louis, Mo., in 1907. There were three
+German, two French, one English, and three American competitors. The
+race was won by Oscar Erbslöh, one of the German competitors, with an
+air-line voyage of 872¼ miles, landing at Bradley Beach, N. J. Alfred
+Leblanc, now a prominent aviator, was second with a voyage of 867
+miles, made in 44 hours. He also landed in New Jersey.
+
+The third race started at Berlin in October, 1908, and was won by the
+Swiss balloon “Helvetia,” piloted by Colonel Schaeck, which landed in
+Norway after having been 74 hours in the air, and covering a journey of
+750 miles. This broke the previous duration record made by Dr. Wegener
+in 1905.
+
+The fourth contest began on October 3, 1909, from Zurich, Switzerland.
+There were seventeen competing balloons, and the race was won by E. W.
+Mix, representing the Aero Club of America, with a voyage of 589 miles.
+
+The fifth contest began at St. Louis, October 17, 1910. It was won by
+Alan P. Hawley and Augustus Post, with the “America II.” They travelled
+1,355 miles in 46 hours, making a new world’s record for distance.
+
+Among other notable voyages may be mentioned that of the “Fielding”
+in a race on July 4, 1908, from Chicago. The landing was made at West
+Shefford, Quebec, the distance travelled being 895 miles.
+
+In November of the same year A. E. Gaudron, Captain Maitland, and C. C.
+Turner, made the longest voyage on record from England. They landed at
+Mateki Derevni, in Russia, having travelled 1,117 miles in 31½ hours.
+They were driven down to the ground by a severe snowstorm.
+
+On December 31, 1908, M. Usuelli, in the balloon “Ruwenzori” left the
+Italian lakes and passed over the Alps at a height of 14,750 feet,
+landing in France. This feat was followed a few weeks later--February
+9, 1909--by Oscar Erbslöh, who left St. Moritz with three passengers,
+crossing the Alps at an altitude of 19,000 feet, and landed at Budapest
+after a voyage of 33 hours. Many voyages over and among the Alps
+have been made by Captain Spelterini, the Swiss aeronaut, and he has
+secured some of the most remarkable photographs of the mountain scenery
+in passing. In these voyages at such great altitudes it is necessary
+to carry cylinders of oxygen to provide a suitable air mixture for
+breathing. In one of his recent voyages Captain Spelterini had the good
+fortune to be carried almost over the summit of Mont Blanc. He ascended
+with three passengers at Chamounix, and landed at Lake Maggiore seven
+hours later, having reached the altitude of 18,700 feet, and travelled
+93 miles.
+
+[Illustration: Photograph of the Alps from a balloon by Captain
+Spelterini.]
+
+In the United States there were several balloon races during the year
+1909, the most important being the St. Louis Centennial race, beginning
+on October 4th. Ten balloons started. The race was won by S. von Phul,
+who covered the distance of 550 miles in 40 hours 40 minutes. Clifford
+B. Harmon and Augustus Post in the balloon “New York” made a new
+duration record for America of 48 hours 26 minutes. They also reached
+the highest altitude attained by an American balloon--24,200 feet.
+
+On October 12th, in a race for the Lahm cup, A. Holland Forbes and Col.
+Max Fleischman won. They left St. Louis, Mo., and landed 19 hours and
+15 minutes later at Beach, Va., near Richmond, having travelled 697
+miles.
+
+In 1910, in the United States, a remarkable race, with thirteen
+competitors, started at Indianapolis. This was the elimination race
+for the International race on October 17th. It was won by Alan P.
+Hawley and Augustus Post in the balloon “America II.” They crossed the
+Alleghany Mountains at an elevation of about 20,000 feet, and landed
+at Warrenton, Va., after being 44 hours 30 minutes in the air; and
+descended only to escape being carried out over Chesapeake Bay.
+
+In recent years the greatest height reached by a balloon was attained
+by the Italian aeronauts Piacenza and Mina in the “Albatross,” on
+August 9, 1909. They went up from Turin to the altitude of 30,350 feet.
+The world’s height record rests with Professors Berson and Suring of
+Berlin, who on July 31, 1901, reached 35,500 feet. The record of 37,000
+feet claimed by Glaisher and Coxwell in their ascension on September 5,
+1862, has been rejected as not authentic for several discrepancies in
+their observations, and on the ground that their instruments were not
+of the highest reliability. As they carried no oxygen, and reported
+that for a time they were both unconscious, it is estimated that the
+highest point they could have reached under the conditions was less
+than 31,000 feet.
+
+The greatest speed ever recorded for any balloon voyage was that
+of Captain von Sigsfield and Dr. Linke in their fatal journey from
+Berlin to Antwerp, during which the velocity of 125 miles per hour was
+recorded.
+
+Ballooning as a sport has a fascination all its own. There is much of
+the spice of adventure in the fact that one’s destiny is quite unknown.
+Floating with the wind, there is no consciousness of motion. Though
+the wind may be travelling at great speed, the balloon seems to be
+in a complete calm. A lady passenger, writing of a recent trip, has
+thus described her experience:--“The world continues slowly to unroll
+itself in ever-varying but ever-beautiful panorama--patchwork fields,
+shimmering silver streaks, toy box churches and houses, and white roads
+like the joints of a jig-saw puzzle. And presently cotton-wool billows
+come creeping up, with purple shadows and fleecy outlines and prismatic
+rainbow effects. Sometimes they invade the car, and shroud it for a
+while in clinging warm white wreaths, and anon they fall below and
+shut out the world with a glorious curtain, and we are all alone in
+perfect silence, in perfect peace, and in a realm made for us alone.
+
+“And so the happy, restful hours go smoothly by, until the earth has
+had enough of it, and rising up more or less rapidly to invade our
+solitude, hits the bottom of our basket, and we step out, or maybe roll
+out, into every-day existence a hundred miles away.”
+
+The perfect smoothness of motion, the absolute quiet, and the absence
+of distracting apparatus combine to render balloon voyaging the most
+delightful mode of transit from place to place. Some of the most
+fascinating bits of descriptive writing are those of aeronauts. The
+following quotation from the report of Capt. A. Hildebrandt, of the
+balloon corps of the Prussian army, will show that although his
+expeditions were wholly scientific, he was far from indifferent to the
+sublimer influences of nature by which he was often surrounded.
+
+In his account of the journey from Berlin to Markaryd, in Sweden, with
+Professor Berson as a companion aeronaut, he says: “The view over Rügen
+and the chalk cliffs of Stubbenkammer and Arkona was splendid: the
+atmosphere was perfectly clear. On the horizon we could see the coasts
+of Sweden and Denmark, looking almost like a thin mist; east and west
+there was nothing but the open sea.
+
+“About 3:15 the balloon was in the middle of the Baltic; right in the
+distance we could just see Rügen and Sweden. The setting of the sun at
+4 P.M. was a truly magnificent spectacle. At a height of 5,250 feet, in
+a perfectly clear atmosphere, the effect was superb. The blaze of color
+was dimly reflected in the east by streaks of a bluish-green. I have
+seen sunsets over France at heights of 10,000 feet, with the Alps, the
+Juras, and the Vosges Mountains in the distance; but this was quite as
+fine.
+
+“The sunsets seen by the mountaineer or the sailor are doubtless,
+magnificent; but I hardly think the spectacle can be finer than that
+spread out before the gaze of the balloonist. The impression is
+increased by the absolute stillness which prevails; no sound of any
+kind is heard.
+
+[Illustration: Landscape as seen from a balloon at an altitude of 3,000
+feet.]
+
+“As soon as the sun went down, it was necessary to throw out some
+ballast, owing to the decrease of temperature.... We reached the
+Swedish coast about 5 o’clock, and passed over Trelleborg at a
+height of 2,000 feet. The question then arose whether to land, or to
+continue through the night. Although it was well past sunset, there
+was sufficient light in consequence of the snow to see our way to
+the ground, and to land quite easily.... However, we wanted to do more
+meteorological work, and it was thought that there was still sufficient
+ballast to take us up to a much greater height. We therefore proposed
+to continue for another sixteen hours during the night, in spite of the
+cold.... Malmö was therefore passed on the left, and the university
+town of Lund on the right. After this the map was of no further use,
+as it was quite dark and we had no lamp. The whole outlook was like a
+transformation scene. Floods of light rose up from Trelleborg, Malmö,
+Copenhagen, Landskrona, Lund, Elsinore, and Helsingborg, while the
+little towns beneath our feet sparkled with many lights. We were now at
+a height of more than 10,000 feet, and consequently all these places
+were within sight. The glistening effect of the snow was heightened by
+the blaze which poured from the lighthouses along the coasts of Sweden
+and Denmark. The sight was as wonderful as that of the sunset, though
+of a totally different nature.”
+
+Captain Hildebrandt’s account of the end of this voyage illustrates the
+spice of adventure which is likely to be encountered when the balloon
+comes down in a strange country. It has its hint also of the hardships
+for which the venturesome aeronaut has to be prepared. He says:--
+
+“Sooner or later the balloon would have been at the mercy of the
+waves. The valve was opened, and the balloon descended through the
+thick clouds. We could see nothing, but the little jerks showed us
+that the guide-rope was touching the ground. In a few seconds we saw
+the ground, and learned that we were descending into a forest which
+enclosed a number of small lakes. At once more ballast was thrown out,
+and we skimmed along over the tops of the trees. Soon we crossed a big
+lake, and saw a place that seemed suitable for a descent. The valve
+was then opened, both of us gave a tug at the ripping cord, and after
+a few bumps we found ourselves on the ground. We had come down in deep
+snow on the side of a wood, about 14 miles from the railway station at
+Markaryd.
+
+[Illustration: Making a landing with the aid of bystanders to pull down
+upon the trail-rope and a holding rope.]
+
+“We packed up our instruments, and began to look out for a cottage;
+but this is not always an easy task in the dead of night in a foreign
+country. However, in a quarter of an hour we found a farm, and
+succeeded in rousing the inmates. A much more difficult job was to
+influence them to open their front door to two men who talked some
+sort of double Dutch, and who suddenly appeared at a farmyard miles
+off the highway in the middle of the night and demanded admittance.
+Berson can talk in six languages, but unfortunately Swedish is not one
+of them. He begged in the most humble way for shelter ... and at the
+end of three-quarters of an hour the farmer opened the door. We showed
+him some pictures of a balloon we had with us, and then they began
+to understand the situation. We were then received with truly Swedish
+hospitality, and provided with supper. They even proposed to let us
+have their beds; but this we naturally declined with many thanks....
+The yard contained hens, pigs, cows, and sheep; but an empty corner
+was found, which was well packed with straw, and served as a couch for
+our tired limbs. We covered ourselves with our great-coats, and tried
+to sleep. But the temperature was 10° Fahr., and as the place was only
+an outhouse of boards roughly nailed together, and the wind whistling
+through the cracks and crevices, we were not sorry when the daylight
+came.”
+
+Lest the possibility of accident to travellers by balloon be judged
+greater than it really is, it may be well to state that records
+collected in Germany in 1906 showed that in 2,061 ascents in which
+7,570 persons participated, only 36 were injured--or but 1 out of 210.
+Since that time, while the balloon itself has remained practically
+unchanged, better knowledge of atmospheric conditions has aided in
+creating an even more favorable record for recent years.
+
+That the day of ordinary ballooning has not been dimmed by the advent
+of the airship and the aeroplane is evidenced by the recently made
+estimate that not less than 800 spherical balloons are in constant
+use almost daily in one part or another of Christendom. And it seems
+entirely reasonable to predict that with a better comprehension of the
+movements of air-currents--to which special knowledge the scientific
+world is now applying its investigations as never before--they will
+come a great increase of interest in simple ballooning as a recreation.
+
+
+
+
+Chapter XIV.
+
+BALLOONS: THE DIRIGIBLE.
+
+    Elongation of
+    gas-bag--Brisson--Meusnier--Air-ballonnets--Scott--Giffard--Haenlein--Tissandier--Renard
+    and Krebs--Schwartz--Santos-Dumont--Von
+    Zeppelin--Roze--Severo--Bradsky-Leboun--The Lebaudy
+    dirigible--Zeppelin II--Parseval I--Unequal wind
+    pressures--Zeppelin III--Nulli Secundus--La
+    Patrie--Ville-de-Paris--Zeppelin IV--Gross I--Parseval
+    II--Clement-Bayard I--Ricardoni’s airship--Gross II--The
+    new Zeppelin II--La Republique--The German fleet of
+    dirigibles--Parseval V--The Deutschland--The Erbslöh--Gross
+    III--Zeppelin VI--The America--Clement-Bayard III--The Capazza
+    lenticular dirigible.
+
+
+The dirigible balloon, or airship, is built on the same general
+principles as the ordinary balloon--that is, with the envelope to
+contain the lifting gas, the car to carry the load, and the suspending
+cordage--but to this is added some form of propelling power to enable
+it to make headway against the wind, and a rudder for steering it.
+
+Almost from the very beginning of ballooning, some method of directing
+the balloon to a pre-determined goal had been sought by inventors.
+Drifting at the fickle pleasure of the prevailing wind did not accord
+with man’s desire for authority and control.
+
+The first step in this direction was the change from the spherical
+form of the gas-bag to an elongated shape, the round form having an
+inclination to turn round and round in the air while floating, and
+having no bow-and-stern structure upon which steering devices could
+operate. The first known proposal in this direction was made by
+Brisson, a French scientist, who suggested building the gas-bag in the
+shape of a horizontal cylinder with conical ends, its length to be
+five or six times its diameter. His idea for its propulsion was the
+employment of large-bladed oars, but he rightly doubted whether human
+strength would prove sufficient to work these rapidly enough to give
+independent motion to the airship.
+
+About the same time another French inventor had actually built a
+balloon with a gas-bag shaped like an egg and placed horizontally with
+the blunt end foremost. The reduction in the resistance of the air to
+this form was so marked that the elongated gas-bag quickly displaced
+the former spherical shape. This balloon was held back from travelling
+at the full speed of the wind by the clever device of a rope dragging
+on the ground; and by a sail rigged so as to act on the wind which
+blew past the retarded balloon, the navigator was able to steer it
+within certain limits. It was the first dirigible balloon.
+
+In the same year the brothers Robert, of Paris, built an airship for
+the Duke of Chartres, under the direction of General Meusnier, a French
+officer of engineers. It was cylindrical, with hemispherical ends, 52
+feet long and 32 feet in diameter, and contained 30,000 cubic feet of
+gas. The gas-bag was made double to prevent the escape of the hydrogen,
+which had proved very troublesome in previous balloons, and it was
+provided with a spherical air balloon inside of the gas-bag, which
+device was expected to preserve the form of the balloon unchanged by
+expanding or contracting, according to the rising or falling of the
+airship. When the ascension was made on July 6, 1784, the air-balloon
+stuck fast in the neck of the gas-bag, and so prevented the escape of
+gas as the hydrogen expanded in the increasing altitude. The gas-bag
+would have burst had not the Duke drawn his sword and slashed a vent
+for the imprisoned gas. The airship came safely to earth.
+
+It was General Meusnier who first suggested the interior ballonnet of
+air to preserve the tense outline of the form of the airship, and the
+elliptical form for the gas-bag was another of his inventions. In the
+building of the airship of the Duke de Chartres he made the further
+suggestion that the space between the two envelopes be filled with
+air, and so connected with the air-pumps that it could be inflated
+or deflated at will. For the motive power he designed three screw
+propellers of one blade each, to be turned unceasingly by a crew of
+eighty men.
+
+Meusnier was killed in battle in 1793, and aeronautics lost its most
+able developer at that era.
+
+[Illustration: The Scott airship, showing the forward “pocket”
+partially drawn in.]
+
+In 1789, Baron Scott, an officer in the French army, devised a
+fish-shaped airship with two outside balloon-shaped “pockets” which
+could be forcibly drawn into the body of the airship to increase its
+density, and thus cause its descent.
+
+It began to be realized that no adequate power existed by which
+balloons could be propelled against even light winds to such a degree
+that they were really controllable, and balloon ascensions came to
+be merely an adjunct of the exhibit of the travelling showman. For
+this reason the early part of the nineteenth century seems barren of
+aeronautical incident as compared with the latter part of the preceding
+century.
+
+In 1848, Hugh Bell, an Englishman, built a cylindrical airship with
+convex pointed ends. It was 55 feet long and 21 feet in diameter. It
+had a keel-shaped framework of tubes to which the long narrow car was
+attached, and there was a screw propeller on each side, to be worked by
+hand, and a rudder to steer with. It failed to work.
+
+In 1852, however, a new era opened for the airship. Henry Giffard, of
+Paris, the inventor of the world-famed injector for steam boilers,
+built an elliptical gas-bag with cigar-shaped ends, 144 feet long,
+and 40 feet in diameter, having a cubic content of 88,000 cubic feet.
+The car was suspended from a rod 66 feet long which hung from the
+net covering the gas-bag. It was equipped with a 3-horse-power steam
+engine which turned a two-bladed screw propeller 11 feet in diameter,
+at the rate of 110 revolutions per minute. Coke was used for fuel.
+The steering was done with a triangular rudder-sail. Upon trial on
+September 24, 1852, the airship proved a success, travelling at the
+rate of nearly 6 miles an hour.
+
+[Illustration: The first Giffard dirigible.]
+
+Giffard built a second airship in 1855, of a much more elongated
+shape--235 feet long and 33 feet in diameter. He used the same engine
+which propelled his first ship. After a successful trial trip, when
+about to land, the gas-bag unaccountably turned up on end, allowing
+the net and car to slide off, and, rising slightly in the air, burst.
+Giffard and his companion escaped unhurt.
+
+Giffard afterward built the large captive balloon for the London
+Exhibition in 1868, and the still larger one for the Paris Exposition
+in 1878. He designed a large airship to be fitted with two boilers and
+a powerful steam-engine, but became blind, and died in 1882.
+
+[Illustration: The Haenlein airship inflated with coal gas and driven
+by a gas-engine.]
+
+In 1865, Paul Haenlein devised a cigar-shaped airship to be inflated
+with coal gas. It was to be propelled by a screw at the front to be
+driven by a gas-engine drawing its fuel from the gas in the body of the
+ship. An interior air-bag was to be expanded as the gas was consumed,
+to keep the shape intact. A second propeller revolving horizontally was
+intended to raise or lower the ship in the air.
+
+It was not until 1872 that he finally secured the building of an
+airship, at Vienna, after his plans. It was 164 feet long, and 30
+feet in diameter. The form of the gas-bag was that described by the
+keel of a ship rotated around the centre line of its deck as an axis.
+The engine was of the Lenoir type, with four horizontal cylinders,
+developing about 6 horse-power, and turned a propeller about 15 feet
+in diameter at the rate of 40 revolutions per minute. The low lifting
+power of the coal gas with which it was inflated caused it to float
+quite near the ground. With a consumption of 250 cubic feet of gas per
+hour, it travelled at a speed of ten miles an hour. The lack of funds
+seems to have prevented further experiments with an invention which was
+at least very promising.
+
+[Illustration: Sketch of the De Lome airship.]
+
+In the same year a dirigible balloon built by Dupuy de Lome for use by
+the French Government during the siege of Paris, was given a trial. It
+was driven by a screw propeller turned by eight men, and although it
+was 118 feet long, and 49 feet in diameter, it made as good a speed
+record as Giffard’s steam-driven airship--six miles an hour.
+
+[Illustration: Car of the Tissandier dirigible; driven by electricity.]
+
+In 1881, the brothers Albert and Gaston Tissandier exhibited at the
+Electrical Exhibition in Paris a model of an electrically driven
+airship, originally designed to establish communication with Paris
+during the siege of the Franco-Prussian War. In 1883, the airship
+built after this model was tried. It was 92 feet long, and 30 feet at
+its largest diameter. The motive power was a Siemens motor run by 24
+bichromate cells of 17 lbs. each. At full speed the motor made 180
+revolutions per minute, developing 1½ horse-power. The pull was 26 lbs.
+The propeller was 9 feet in diameter, and a speed of a little more than
+6 miles an hour was attained.
+
+[Illustration: Sketch of the Renard and Krebs airship _La France_,
+driven by a storage battery.]
+
+In 1884, two French army engineers, Renard and Krebs, built an airship,
+the now historic _La France_, with the shape of a submarine torpedo. It
+was 165 feet long and about 27 feet in diameter at the largest part. It
+had a gas content of 66,000 cubic feet. A 9 horse-power Gramme electric
+motor was installed, driven by a storage battery. This operated the
+screw propeller 20 feet in diameter, which was placed at the forward
+end of the long car. The trial was made on the 9th of August, and was
+a complete success. The ship was sailed with the wind for about 2½
+miles, and then turned about and made its way back against the wind
+till it stood directly over its starting point, and was drawn down to
+the ground by its anchor ropes. The trip of about 5 miles was made in
+23 minutes. In seven voyages undertaken the airship was steered back
+safely to its starting point five times.
+
+This first airship which really deserved the name marked an era in the
+development of this type of aircraft. In view of its complete success
+it is astonishing that nothing further was done in this line in France
+for fifteen years, when Santos-Dumont began his series of record-making
+flights. Within this period, however, the gasoline motor had been
+adapted to the needs of the automobile, and thus a new and light-weight
+engine, suitable in every respect, had been placed within the reach of
+aeronauts.
+
+In the meantime, a new idea had been brought to the stage of actual
+trial. In 1893, in St. Petersburg, David Schwartz built a rigid
+airship, the gas receptacle of which was sheet aluminum. It was braced
+by aluminum tubes, but while being inflated the interior work was so
+badly broken that it was abandoned.
+
+Schwartz made a second attempt in Berlin in 1897. The airship was
+safely inflated, and managed to hold its position against a wind
+blowing 17 miles an hour, but could not make headway against it. After
+the gas had been withdrawn, and before it could be put under shelter,
+a severe windstorm damaged it, and the mob of spectators speedily
+demolished it in the craze for souvenirs of the occasion.
+
+[Illustration: Wreck of the Schwartz aluminum airship, at Berlin, in
+1897.]
+
+[Illustration:
+
+    The type of the earlier Santos-Dumont dirigibles. This shape
+    showed a tendency to “buckle,” or double up in the middle like a
+    jackknife. To avoid this the later Santos-Dumonts were of much
+    larger proportional diameter amidships.]
+
+In 1898, the young Brazilian, Santos-Dumont, came to Paris imbued with
+aeronautic zeal, and determined to build a dirigible balloon that
+would surpass the former achievements of Giffard and Renard, which he
+felt confident were but hints of what might be accomplished by that
+type of airship. He began the construction of the series of dirigible
+balloons which eventually numbered 12, each successive one being an
+improvement on the preceding. He made use of the air-bag suggested
+by Meusnier for the balloon of the Duke of Chartres in 1784, although
+in an original way, at first using a pneumatic pump to inflate it, and
+later a rotatory fan. Neither prevented the gas-bag from “buckling” and
+coming down with consequences more or less serious to the airship--but
+Santos-Dumont himself always escaped injury. His own record of his
+voyages in his book, _My Air-Ships_, gives a more detailed account
+of his contrivances and inventions than can be permitted here. If
+Santos-Dumont did not greatly surpass his predecessors, he is at least
+to be credited with an enthusiasm which aroused the interest of the
+whole world in the problems of aeronautics; and his later achievements
+in the building and flying of aeroplanes give him a unique place in the
+history of man’s conquest of the air.
+
+[Illustration: Type of the later Santos-Dumont’s dirigibles.]
+
+In 1900, Count von Zeppelin’s great airship, which had been building
+for nearly two years, was ready for trial. It had the form of a prism
+of 24 sides, with the ends arching to a blunt point. It was 420 feet
+long, and 38 feet in diameter. The structure was rigid, of aluminum
+lattice work, divided into 17 compartments, each of which had a
+separate gas-bag shaped to fit its compartment. Over all was an outer
+envelope of linen and silk treated with pegamoid. A triangular keel of
+aluminum lattice strengthened the whole, and there were two cars of
+aluminum attached to the keel. Each car held a 16 horse-power Daimler
+gasoline motor, operating two four-bladed screw propellers which were
+rigidly connected with the frame of the ship a little below the level
+of its axis. A sliding weight was run to either end of the keel as
+might be required to depress the head or tail, in order to rise or fall
+in the air. The cars were in the shape of boats, and the ship was built
+in a floating shed on the Lake of Constance near Friedrichshafen.
+At the trial the airship was floated out on the lake, the car-boats
+resting on the water. Several accidents happened, so that though the
+ship got up into the air it could not be managed, and was brought down
+to the water again without injury. In a second attempt a speed of 20
+miles an hour was attained. The construction was found to be not strong
+enough for the great length of the body, the envelope of the balloon
+was not sufficiently gas tight, and the engines were not powerful
+enough. But few trips were made in it, and they were short. The Count
+set himself to work to raise money to build another ship, which he did
+five years later.
+
+[Illustration: View of the Zeppelin I, with portion of the aluminum
+shell and external fabric removed to show the internal framing and
+separate balloons. In the distance is shown the great balloon shed.]
+
+In 1901, an inventor named Roze built an airship in Colombo, having two
+gas envelopes with the engines and car placed between them. He expected
+to do away with the rolling and pitching of single airships by the
+double form, but the ship did not work satisfactorily, ascending to
+barely 50 feet.
+
+In 1902, Augusto Severo, a Brazilian, arranged an airship with the
+propelling screws at the axis of the gas-bag, one at each end of the
+ship. Instead of a rudder, he provided two small propellers to work in
+a vertical plane and swing the ship sideways. Soon after ascending
+it was noticed that the propellers were not working properly, and a
+few minutes later the car was seen to be in flames and the balloon
+exploded. Severo and his companion Sache were killed, falling 1,300
+feet.
+
+[Illustration: Sketch of the Severo airship, showing arrangement of
+the driving propellers on the axis of the gas-bag, and the steering
+propellers.]
+
+[Illustration:
+
+    End view of Severo’s airship, showing the longitudinal division
+    of the gas-bag to allow the driving shaft of the propellers to be
+    placed at the axis of the balloon.]
+
+In the same year Baron Bradsky-Leboun built an airship with partitions
+in the gas-bag which was just large enough to counterbalance the weight
+of the ship and its operators. It was lifted or lowered by a propeller
+working horizontally. Another propeller drove the ship forward. Through
+some lack of stability the car turned over, throwing out the two
+aeronauts, who fell 300 feet and were instantly killed.
+
+[Illustration: The first Lebaudy airship.]
+
+In 1902, a dirigible balloon was built for the brothers Lebaudy by the
+engineer Juillot and the aeronaut Surcouf. The gas envelope was made
+cigar-shaped and fastened rigidly to a rigid elliptical keel-shaped
+floor 70 feet long and 19 feet wide, made of steel tubes--the object
+being to prevent rolling and pitching. It was provided with both
+horizontal and vertical rudders. A 35 horse-power Daimler-Mercedes
+motor was used to turn two twin-bladed screws, each of 9 feet in
+diameter. Between the 25th of October, 1902, and the 21st of November,
+1903, 33 experimental voyages were made, the longest being 61 miles in
+2 hours and 46 minutes; 38.7 miles in 1 hour and 41 minutes; 23 miles
+in 1 hour and 36 minutes.
+
+[Illustration: Framing of the floor and keel of the Lebaudy airship.]
+
+In 1904 this ship was rebuilt. It was lengthened to 190 feet and the
+rear end rounded off. Its capacity was increased to 94,000 cubic feet,
+and a new covering of the yellow calico which had worked so well on the
+first model was used on the new one. It was coated with rubber both on
+the outside and inside. The interior air-bag was increased in size to
+17,650 cubic feet, and partitioned into three compartments. During 1904
+and 1905 30 voyages were made, carrying in all 195 passengers.
+
+[Illustration: The car and propellers of the Lebaudy airship.]
+
+The success of this airship led to a series of trials under the
+direction of the French army, and in all of these trials it proved
+satisfactory. After the 76th successful voyage it was retired for the
+winter of 1905-6.
+
+In November, 1905, the rebuilt Zeppelin airship was put upon trial.
+While superior to the first one, it met with serious accident, and was
+completely wrecked by a windstorm in January, 1906.
+
+In May, 1906, Major von Parseval’s non-rigid airship passed through
+its first trials successfully. This airship may be packed into small
+compass for transportation, and is especially adapted for military
+use. In plan it is slightly different from previous types, having
+two air-bags, one in each end of the envelope, and the front end is
+hemispherical instead of pointed.
+
+As the airship is designed to force its way through the air, instead
+of floating placidly in it, it is evident that it must have a certain
+tenseness of outline in order to retain its shape, and resist being
+doubled up by the resistance it encounters. It is estimated that the
+average velocity of the wind at the elevation at which the airship
+sails is 18 miles per hour. If the speed of the ship is to be 20
+miles per hour, as related to stations on the ground, and if it is
+obliged to sail against the wind, it is plain that the wind pressure
+which it is compelled to meet is 38 miles per hour--a gale of no mean
+proportions. When the large expanse of the great gas-bags is taken into
+consideration, it is evident that ordinary balloon construction is not
+sufficient.
+
+Attempts have been made to meet the outside pressure from the wind and
+air-resistance by producing mechanically a counter-pressure from the
+inside. Air-bags are placed inside the cavity of the gas-bag, usually
+one near each end of the airship, and these are inflated by pumping
+air into them under pressure. In this way an outward pressure of as
+much as 7 lbs. to the square foot may be produced, equivalent to the
+resistance of air at a speed (either of the wind, or of the airship, or
+of both combined) of 48 miles per hour. It is evident, however, that
+the pressure upon the front end of an airship making headway against a
+strong wind will be much greater than the pressure at the rear end, or
+even than that amidships. It was this uneven pressure upon the outside
+of the gas-bag that doubled up the first two airships of Santos-Dumont,
+and led him to increase the proportional girth at the amidship section
+in his later dirigibles. The great difficulty of adjusting these
+varying pressures warrants the adherence of Count von Zeppelin to his
+design with the rigid structure and metallic sheathing.
+
+The loss of the second Zeppelin airship so discouraged its designer
+that he decided to withdraw from further aeronautical work. But the
+German Government prevailed on him to continue, and by October, 1906,
+he had the Zeppelin III in the air. This airship was larger than
+Zeppelin II in both length and diameter, and held 135,000 cubic feet
+more of gas. The motive power was supplied by two gasoline motors,
+each of 85 horse-power. The gas envelope had 16 sides, instead of 24,
+as in the earlier ship. At its trial the Zeppelin III proved highly
+successful. It made a trip of 69 miles, with 11 passengers, in 2¼
+hours--a speed of about 30 miles an hour.
+
+[Illustration: The Zeppelin III backing out of the floating shed at
+Friedrichshafen. The illustration shows the added fin at the top, the
+rudders, dipping planes, and balancing planes.]
+
+The German Government now made an offer of $500,000 for an airship
+which would remain continuously in the air for 24 hours, and be able to
+land safely. Count von Zeppelin immediately began work upon his No. IV,
+in the effort to meet these requirements, in the meantime continuing
+trips with No. III. The most remarkable of these trips was made in
+September, 1907, a journey of 211 miles in 8 hours.
+
+In October, 1907, the English airship “Nulli Secundus” was given its
+first trial. The gas envelope had been made of goldbeater’s skins,
+which are considered impermeable to the contained gas, but are very
+expensive. This airship was of the non-rigid type. It made the trip
+from Aldershot to London, a distance of 50 miles, in 3½ hours--an
+apparent speed of 14 miles per hour, lacking information as to the aid
+or hindrance of the prevailing wind. Several other trials were made,
+but with small success.
+
+The offer of the German Government had stimulated other German builders
+besides Count von Zeppelin, and on October 28, 1907, the Parseval I,
+which had been improved, and the new Gross dirigible, competed for the
+government prize, at Berlin. The Parseval kept afloat for 6½ hours, and
+the Gross for 8¼ hours.
+
+Meanwhile, in France, the Lebaudys had been building a new airship
+which was named “La Patrie.” It was 197 feet long and 34 feet in
+diameter. In a trial for altitude it was driven to an elevation of
+4,300 feet. On November 23, 1907, the “Patrie” set out from Paris for
+Verdun, a distance of 146 miles. The journey was made in 6¾ hours,
+at an average speed of 25 miles per hour, and the fuel carried was
+sufficient to have continued the journey 50 miles further. Soon after
+reaching Verdun a severe gale tore the airship away from the regiment
+of soldiers detailed to assist the anchors in holding it down, and it
+disappeared into the clouds. It is known to have passed over England,
+for parts of its machinery were picked up at several points, and some
+days later the gas-bag was seen floating in the North Sea.
+
+[Illustration: The “Ville-de-Paris” of M. de la Meurthe.]
+
+Following close upon the ill-fated “Patrie” came the “Ville-de-Paris,”
+a dirigible which had been built by Surcouf for M. Henri Deutsch de
+la Meurthe, an eminent patron of aeronautic experiments. In size this
+airship was almost identical with the lost “Patrie,” but it was quite
+different in appearance. It did not have the flat framework at the
+bottom of the gas envelope, but was entirely round in section, and the
+long car was suspended below. At the rear the gas-bag was contracted
+to a cylindrical form, and four groups of two ballonnets each were
+attached to act as stabilizers. It was offered by M. de la Meurthe to
+the French Government to take the place of the “Patrie” in the army
+manœuvres at Verdun, and on January 15, 1908, made the trip thither
+from Paris in about 7 hours. It was found that the ballonnets exerted
+considerable drag upon the ship.
+
+In June, 1908, the great “Zeppelin IV” was completed and given its
+preliminary trials, and on July 1 it started on its first long journey.
+Leaving Friedrichshafen, its route was along the northerly shore of
+Lake Constance nearly to Schaffhausen, then southward to and around
+Lake Lucerne, thence northward to Zurich, thence eastward to Lake
+Constance, and to its shed at Friedrichshafen. The distance traversed
+was 236 miles, and the time consumed 12 hours. This voyage without a
+single mishap aroused the greatest enthusiasm among the German people.
+After several short flights, during which the King of Württemberg, the
+Queen, and some of the royal princes were passengers, the Zeppelin IV
+set out on August 4 to win the Government reward by making the 24-hour
+flight. Sailing eastward from Friedrichshafen it passed over Basle,
+then turning northward it followed the valley of the Rhine, passing
+over Strasburg and Mannheim, and had nearly reached Mayence when a
+slight accident necessitated a landing. Repairs were made, and the
+journey resumed after nightfall. Mayence was reached at 11 P. M., and
+the return trip begun. When passing over Stuttgart, at 6 A. M., a leak
+was discovered, and a landing was made at Echterdingen, a few miles
+farther on. Here, while repairs were being made, a squall struck the
+airship and bumped it heavily on the ground. Some gasoline was spilled,
+in some unknown way, which caught fire, and in a few moments the great
+balloon was totally destroyed. It had been in continuous flight 11
+hours up to the time of the first landing, and altogether 20¾ hours,
+and had travelled 258 miles.
+
+The German people immediately started a public subscription to provide
+Count von Zeppelin with the funds needed to build another airship,
+and in a few days the sum of $1,500,000 was raised and turned over to
+the unfortunate inventor. The “Zeppelin III” was taken in hand, and
+lengthened, and more powerful engines installed.
+
+The “Gross II” was ready to make its attempt for the Government prize
+on September 11, 1908. It sailed from Tegel to Magdeburg and back to
+Tegel, a distance of 176 miles, in 13 hours, without landing.
+
+[Illustration: The Clement-Bayard dirigible entering its shed.]
+
+Four days later the “Parseval II” made a trip between the same points
+in 11½ hours, but cut the distance travelled down to 157 miles. In
+October, the “Parseval II” was sent up for an altitude test, and rose
+to a height of 5,000 feet above Tegel, hovering over the city for
+upward of an hour.
+
+During 1908, an airship designed by M. Clement, the noted motor-car
+builder, was being constructed in France. It made its first voyage on
+October 29, carrying seven passengers from Sartrouville to Paris and
+back, at a speed of from 25 to 30 miles per hour. The illustration
+gives a very good idea of the peculiar ballonnets attached to the rear
+end of the gas envelope. These ballonnets open into the large gas-bag,
+and are practically a part of it.
+
+In Italy a remarkable dirigible has been built by Captain Ricaldoni,
+for military purposes. It has the form of a fish, blunt forward, and
+tapering straight away to the rear. It has a large finlike surface on
+the under side of the gas-bag toward the rear. Its performances show
+that its efficiency as compared with its motive power is larger than
+any other dirigible in commission.
+
+[Illustration: Engine of the Clement-Bayard dirigible; 7-cylinder; 55
+horse-power; weighing only 155 pounds.]
+
+In May, 1909, the rebuilt “Zeppelin III,” now rechristened “Zeppelin
+II,” after many successful short flights was prepared for the
+Government trial. On May 29, 1909, with a crew of six men, Count von
+Zeppelin started from Friedrichshafen for Berlin, 360 miles away. The
+great ship passed over Ulm, Nuremburg, Bayreuth, and Leipzig; and
+here it encountered so strong a head wind from the north, that it was
+decided to turn about at Bitterfeld and return to Friedrichshafen. The
+distance travelled had been nearly 300 miles in 21 hours. The course
+followed was quite irregular, and took the ship over Wurtzburg, and
+by a wide detour to Heilbron and Stuttgart. The supply of gasoline
+running low, it was decided to land at Goeppingen, where more could be
+obtained. It was raining heavily, and through some mistake in steering,
+or some sudden veering of the wind, the prow of the great dirigible
+came into collision with a tree upon the hillside. The envelope was
+badly torn, and a part of the aluminum inner structure wrecked.
+However, the mechanics on board were able to make such repairs that
+the ship was able to resume the voyage the next day, and made port
+without further mishap. The vessel having been 38 hours in the air at
+the time of the accident, so much of the Government’s stipulations
+had been complied with. But it had not succeeded in landing safely.
+Nevertheless it was accepted by the Government. The entire journey has
+been variously estimated at from 680 to 900 miles, either figure being
+a record for dirigibles.
+
+[Illustration: Accident to the new “Zeppelin II” at Goeppingen. The
+damage was repaired and the airship continued its voyage the next day.]
+
+On August 4, the dirigible “Gross II” made a voyage from Berlin to
+Apolda, and returned; a distance of 290 miles in 16 hours. This airship
+also was accepted by the German Government and added to its fleet.
+
+In August, the Zeppelin II was successfully sailed to Berlin, where
+Count von Zeppelin was welcomed by an immense and enthusiastic
+multitude of his countrymen, including the Emperor and the royal family.
+
+On September 26, the new French dirigible, “La Republique,” built on
+the model of the successful Lebaudy airships, met with an accident
+while in the air. A blade of one of the propellers broke and slashed
+into the envelope. The ship fell from a height of 6,000 feet, and its
+crew of four men lost their lives.
+
+[Illustration: View of the damaged Zeppelin from the front, showing the
+tree against which it collided.]
+
+On April 22, 1910, a fleet of German dirigibles, comprising the
+“Zeppelin II,” the “Gross II,” and the “Parseval I,” sailed from
+Cologne to Hamburg, where they were reviewed by Emperor William. A
+strong wind having arisen, the “Gross II,” which is of the semi-rigid
+type, was deflated, and shipped back to Cologne by rail. The non-rigid
+“Parseval” made the return flight in safety. The rigid “Zeppelin II”
+started on the return voyage, but was compelled to descend at Limburg,
+where it was moored. The wind increasing, it was forced away, and
+finally was driven to the ground at Weilburg and demolished.
+
+In May, 1910, the “Parseval V,” the smallest dirigible so far
+constructed, being but 90 feet in length, was put upon its trial trip.
+It made a circular voyage of 80 miles in 4 hours.
+
+For several months a great Zeppelin passenger dirigible had been
+building by a stock company financed by German capital, under the
+direction of the dauntless Count von Zeppelin. It was 490 feet long,
+with a capacity of 666,900 cubic feet. A passenger cabin was built with
+¼-inch mahogany veneer upon a framework of aluminum, the inside being
+decorated with panels of rosewood inlaid with mother-of-pearl. The
+seats were wicker chairs, and the window openings had no glass. It was
+christened the “Deutschland.”
+
+After many days waiting for propitious weather the first “air-liner”
+set sail on June 22, 1910, from Friedrichshafen for Düsseldorf,
+carrying 20 passengers who had paid $50 each for their passage. In
+addition there were 13 other persons on board.
+
+The start was made at three o’clock in the morning, and the course
+laid was up the valley of the Rhine, as far as Cologne. Düsseldorf was
+reached at three o’clock in the afternoon, the airline distance of 300
+miles having been covered in 9 hours of actual sailing. From Mannheim
+to Düsseldorf, favored by the wind, the great ship reached the speed of
+50 miles per hour, for this part of the trip, outstripping the fastest
+express trains which consume 6 hours in the winding track up the valley.
+
+The next morning the “Deutschland” left Düsseldorf on an excursion
+trip, carrying several ladies among its passengers. The voyage was in
+every way a great success, and public enthusiasm was widespread.
+
+On June 29, a test trip was decided upon. No passengers were taken,
+but 19 newspaper correspondents were invited guests. The Count had
+been warned of weather disturbances in the neighborhood, but he either
+disregarded them or felt confidence in his craft. It was intended that
+the voyage should last four hours, but the airship soon encountered a
+storm, and after 6 hours of futile striving against it, the fuel gave
+out. Caught in an upward draft, the “Deutschland” rose to an altitude
+of over 5,000 feet, losing considerable gas, and then, entering a
+rainstorm, was heavily laden with moisture. Suddenly, without definite
+reason, it began to fall vertically, and in a few moments had crashed
+into the tops of the trees of the Teutoberg forest. No one on board
+received more than slight injury, and all alighted safely by means of
+ladders. The “Deutschland” was a wreck, and was taken apart and shipped
+back to Friedrichshafen.
+
+On July 13, another giant passenger airship, designed by Oscar Erbslöh,
+who won the international balloon race in 1907 by a voyage from St.
+Louis to Asbury Park, met with fatal disaster. It was sailing near
+Cologne at an altitude of about 2,500 feet when it burst, and Erbslöh
+and his four companions were killed in the fall.
+
+On July 28, the “Gross III” left Berlin with the object of beating
+the long distance record for dirigibles. Soon after passing Gotha the
+airship returned to that place, and abandoned the attempt. In 13 hours
+a distance of 260 miles had been traversed.
+
+Undismayed by the catastrophes which had destroyed his airships almost
+as fast as he built them, Count von Zeppelin had his number VI ready
+to sail on September 3. With a crew of seven and twelve passengers he
+sailed from Baden to Heidelberg--53 miles in 65 minutes. It was put
+into commission as an excursion craft, and made several successful
+voyages. On September 14, as it was being placed in its shed at the
+close of a journey, it took fire unaccountably, and was destroyed
+together with the shed, a part of the framework only remaining.
+
+On October 15, 1910, the Wellman dirigible “America” which had been
+in preparation for many weeks, left Asbury Park in an attempt to
+cross the Atlantic. Its balloon was 228 feet long, with a diameter
+of 52 feet, containing 345,000 cubic feet of gas. The car was 156
+feet in length, and was arranged as a tank in which 1,250 gallons of
+gasoline were carried. A lifeboat was attached underneath the car.
+There were two engines, each of 80 horse-power, and an auxiliary motor
+of 10 horse-power. Sleeping quarters were provided for the crew of
+six, and the balloon was fitted with a wireless telegraph system.
+All went well until off the island of Nantucket, where strong north
+winds were encountered, and the dirigible was swept southward toward
+Bermuda. As an aid in keeping the airship at an elevation of about 200
+feet above the sea, an enlarged trail-rope, called the equilibrator,
+had been constructed of cans which were filled with gasoline. This
+appendage weighed 1½ tons, and the lower part of it was expected to
+float upon the sea. In practice it was found that the jarring of this
+equilibrator, when the sea became rough, disarranged the machinery,
+so that the propellers would not work, and the balloon was compelled
+to drift with the wind. Toward evening of the second day a ship was
+sighted, and the America’s crew were rescued. The airship floated away
+in the gale, and was soon out of sight.
+
+On October 16, a new Clement-Bayard dirigible, with seven men on board,
+left Paris at 7.15 o’clock in the morning, and sailed for London. At
+1 P. M. it circled St. Paul’s Cathedral, and landed at the hangar at
+Wormwood Scrubbs a half hour later. The distance of 259 miles (airline)
+was traversed at the rate of 41 miles per hour, and the journey
+surpassed in speed any previous journey by any other form of conveyance.
+
+[Illustration:
+
+    _Copyright by Pictorial News Company._
+
+Wellman dirigible “America” starting for Europe, October 15, 1910.]
+
+On November 5, 1910, the young Welsh aeronaut, Ernest T. Willows, who
+sailed his small dirigible from Cardiff to London in August, made a
+trip from London across the English Channel to Douai, France. This is
+the third time within a month that the Channel had been crossed by
+airships.
+
+[Illustration:
+
+    Diagram of the Capazza dirigible from the side. _A A_,
+    stabilizing fins; _B_, air-ballonnet; _R_, rudder; _M M_, motors;
+    _FS_, forward propeller; _SS_, stern propeller.]
+
+Toward the close of 1910, 52 dirigibles were in commission or in
+process of construction. In the United States there were 7; in Belgium,
+2; in England, 6; in France, 12; in Germany, 14; in Italy, 5; in
+Russia, 1; in Spain, 1.
+
+The new Capazza dirigible is a decided departure from all preceding
+constructions, and may mark a new era in the navigation of the air.
+Its gas envelope is shaped like a lens, or a lentil, and is arranged to
+sail flatwise with the horizon, thus partaking of the aeroplane as well
+as the balloon type. No definite facts concerning its achievements have
+been published.
+
+[Illustration: Capazza dirigible from the front. From above it is an
+exact circle in outline.]
+
+
+
+
+Chapter XV.
+
+BALLOONS: HOW TO OPERATE.
+
+    Preliminary
+    inspection--Instruments--Accessories--Ballast--Inflating--Attaching
+    the car--The ascension--Controls--Landing--Some things to be
+    considered--After landing--Precautions.
+
+
+The actual operation of a balloon is always entrusted to an experienced
+pilot, or “captain” as he is often called, because he is in command,
+and his authority must be recognized instantly whenever an order
+is given. Nevertheless, it is often of great importance that every
+passenger shall understand the details of managing the balloon in case
+of need; and a well-informed passenger is greatly to be preferred to an
+ignorant one.
+
+It is ordinarily one of the duties of the captain to inspect the
+balloon thoroughly; to see that there are no holes in the gas-bag, that
+the valve is in perfect working order, and particularly that the valve
+rope and the ripping cord are not tangled. He should also gather the
+instruments and equipment to be carried.
+
+The instruments are usually an aneroid barometer, and perhaps a mercury
+barometer, a barograph (recording barometer), a psychrometer (recording
+thermometer), a clock, a compass, and an outfit of maps of the country
+over which it is possible that the balloon may float. Telegraph blanks,
+railroad time tables, etc., may be found of great service. A camera
+with a supply of plates will be indispensable almost, and the camera
+should be provided with a yellow screen for photographing clouds or
+distant objects.
+
+The ballast should be inspected, to be sure that it is of dry sand,
+free from stones; or if water is used for ballast, it should have the
+proper admixture of glycerine to prevent freezing.
+
+It is essential that the inflating be properly done, and the captain
+should be competent to direct this process in detail, if necessary.
+What is called the “circular method” is the simplest, and is entirely
+satisfactory unless the balloon is being filled with pure hydrogen for
+a very high ascent, in which case it will doubtless be in the hands of
+experts.
+
+When inflating with coal-gas, the supply is usually taken from a
+large pipe adapted for the purpose. At a convenient distance from the
+gas-main the ground is made smooth, and the ground cloths are spread
+out and pegged down to keep them in place.
+
+The folded balloon is laid out on the cloths with the neck opening
+toward the gas-pipe. The balloon is then unfolded, and so disposed that
+the valve will be uppermost, and in the centre of a circle embracing
+the upper half of the sphere of the balloon, the opening of the neck
+projecting a few inches beyond the rim of the circle. The hose from the
+gas-main may then be connected with the socket in the neck.
+
+[Illustration: Balloon laid out in the circular method, ready for
+inflation. The valve is seen at the centre. The neck is at the right.]
+
+Having made sure that the ripping cord and the valve rope are free from
+each other, and properly connected with their active parts, and that
+the valve is fastened in place, the net is laid over the whole, and
+spread out symmetrically. A few bags of ballast are hooked into the net
+around the circumference of the balloon as it lies, and the assistants
+distributed around it. It should be the duty of one man to hold the
+neck of the balloon, and not to leave it for any purpose whatever. The
+gas may then be turned on, and, as the balloon fills, more bags of
+ballast are hung symmetrically around the net; and all are continually
+moved downward as the balloon rises.
+
+Constant watching is necessary during the inflation, so that the
+material of the balloon opens fully without creases, and the net
+preserves its correct position. When the inflation is finished the hoop
+and car are to be hooked in place. The car should be fitted up and hung
+with an abundance of ballast. Disconnect the gas hose and tie the neck
+of the balloon in such fashion that it may be opened with a pull of the
+cord when the ascent begins.
+
+The ballast is then transferred to the hoop, or ring, and the balloon
+allowed to rise until this is clear of the ground. The car is then
+moved underneath, and the ballast moved down from the ring into it. The
+trail-rope should be made fast to the car directly under the ripping
+panel, the object being to retard that side of the balloon in landing,
+so that the gas may escape freely when the panel is torn open, and not
+underneath the balloon, as would happen if the balloon came to earth
+with the ripping panel underneath.
+
+The balloon is now ready to start, and the captain and passengers
+take their places in the car. The neck of the balloon is opened, and
+a glance upward will determine if the valve rope hangs freely through
+it. The lower end of this should be tied to one of the car ropes. The
+cord to the ripping panel should be tied in a different place, and in
+such fashion that no mistake can be made between them. The assistants
+stand around the edge of the basket, holding it so that it shall not
+rise until the word is given. The captain then adjusts the load of
+ballast, throwing off sufficient to allow the balloon to pull upward
+lightly against the men who are holding it. A little more ballast is
+then thrown off, and the word given to let go. The trail-rope should be
+in charge of some one who will see that it lifts freely from the ground.
+
+The balloon rises into the air to an altitude where a bulk of the
+higher and therefore lighter air equal to the bulk of the balloon has
+exactly the same weight. This is ordinarily about 2,000 feet. If the
+sun should be shining the gas in the balloon will be expanded by the
+heat, and some of it will be forced out through the neck. This explains
+the importance of the open neck. In some of the early ascensions no
+such provision for the expansion of the gas was made, and the balloons
+burst with disastrous consequences.
+
+[Illustration: Inflating a military balloon. The net is being adjusted
+smoothly as the balloon rises. The bags of ballast surround the balloon
+ready to be attached as soon as the buoyancy of the gas lifts it from
+the earth.]
+
+When some of the gas has been driven out by the heat, there is less
+_weight_ of gas in the balloon, though it occupies the same space. It
+therefore has a tendency to rise still higher. On the other hand, if
+it passes into a cloud, or the sun is otherwise obscured, the volume
+of the gas will contract; it will become denser, and the balloon will
+descend. To check the descent the load carried by the balloon must
+be lightened, and this is accomplished by throwing out some ballast;
+generally, a few handfuls is enough.
+
+There is always more or less leakage of gas through the envelope as
+well as from the neck, and this also lessens the lifting power. To
+restore the balance, more ballast must be thrown out, and in this way
+an approximate level is kept during the journey.
+
+When the ballast is nearly exhausted it will be necessary to come down,
+for a comfortable landing cannot be made without the use of ballast.
+A good landing place having been selected, the valve is opened, and
+the balloon brought down within a few yards of the ground. The ripping
+cord is then pulled and ballast thrown out so that the basket will
+touch as lightly as possible. Some aeronauts use a small anchor or
+grapnel to assist in making a landing, but on a windy day, when the car
+is liable to do some bumping before coming to rest, the grapnel often
+makes matters much worse for the passengers by a series of holdings and
+slippings, and sometimes causes a destructive strain upon the balloon.
+
+In making an ascent with a balloon full of gas there is certain to be a
+waste of gas as it expands. This expansion is due not only to the heat
+of the sun, but also to the lighter pressure of the air in the upper
+altitudes. It is therefore the custom with some aeronauts to ascend
+with a partially filled balloon, allowing the expansion to completely
+fill it. This process is particularly advised if a very high altitude
+is sought. When it is desired to make a long voyage it is wise to make
+the start at twilight, and so avoid the heat of the sun. The balloon
+will then float along on an almost unchanging level without expenditure
+of ballast. Rain and even the moisture from clouds will sometimes wet
+the balloon so that it will cause a much greater loss of ballast than
+would have been required to be thrown out to rise above the cloud or
+storm. Such details in the handling of a balloon during a voyage will
+demand the skilled judgment of the captain.
+
+[Illustration: A balloon ready for ascent. Notice that the neck is
+still tied.]
+
+The trail-rope is a valuable adjunct when the balloon is travelling
+near the ground. The longer the part of the trail-rope that is dragging
+on the ground the less weight the balloon is carrying. And at night,
+when it is impossible to tell the direction in which one is travelling
+in any other way, the line of the trailing rope will show the direction
+from which the wind is blowing, and hence the drift of the balloon.
+
+The care of the balloon and its instruments upon landing falls upon
+the captain, for he is not likely to find assistants at hand competent
+to relieve him of any part of the necessary work. The car and the ring
+are first detached. The ropes are laid out free and clear, and the
+valve is unscrewed and taken off. The material of the balloon is folded
+smoothly, gore by gore. The ballast bags are emptied. After all is
+bundled up it should be packed in the car, the covering cloth bound on
+with ropes, and definite instructions affixed for transportation to the
+starting-point.
+
+It is apparent that the whole of the gas is lost at the end of the
+journey. The cost of this is the largest expense of ballooning. For a
+small balloon of about 50,000 cubic feet, the coal-gas for inflating
+will cost about $35 to $40. If hydrogen is used, it will cost probably
+ten times as much.
+
+In important voyages it is customary to send up pilot balloons, to
+discover the direction of the wind currents at the different levels,
+so that the level which promises the best may be selected before the
+balloon leaves the ground. A study of the weather conditions throughout
+the surrounding country is a wise precaution, and no start should
+be made if a storm is imminent. The extent of control possible in
+ballooning being so limited, all risks should be scrupulously avoided,
+both before and during the voyage, and nothing left to haphazard.
+
+
+
+
+Chapter XVI.
+
+BALLOONS: HOW TO MAKE.
+
+    The fabrics used--Preliminary varnishing--Varnishes--Rubberized
+    fabrics--Pegamoid--Weight of varnish--Latitudes of the
+    balloon--Calculating gores--Laying out patterns and
+    cutting--Sewing--Varnishing--Drying--Oiling--The neck--The
+    valve--The net--The basket.
+
+
+The making of a balloon is almost always placed in the hands of a
+professional balloon-maker. But as the use of balloons increases, and
+their owners multiply, it is becoming a matter of importance that the
+most improved methods of making them should be known to the intending
+purchaser, as well as to the amateur who wishes to construct his own
+balloon.
+
+The fabric of which the gas envelope is made may be either silk,
+cotton (percale), or linen. It should be of a tight, diagonal weave,
+of uniform and strong threads in both warp and woof, unbleached, and
+without dressing, or finish. If it is colored, care should be exercised
+that the dye is one that will not affect injuriously the strength or
+texture of the fabric. Lightness in weight, and great strength (as
+tested by tearing), are the essentials.
+
+The finest German percale weighs about 2½ ounces per square yard;
+Russian percale, 3⅓ ounces, and French percale, 3¾ounces, per square
+yard. The white silk used in Russian military balloons weighs about
+the same as German percale, but is very much stronger. Pongee silk is
+a trifle heavier. The silk used for sounding balloons is much lighter,
+weighing only a little over one ounce to the square yard.
+
+Goldbeater’s skin and rubber have been used to some extent, but the
+great cost of the former places it in reach only of governmental
+departments, and the latter is of use only in small balloons for
+scientific work--up to about 175 cubic feet capacity.
+
+The fabric is first to be varnished, to fill up the pores and render
+it gas-tight. For this purpose a thin linseed-oil varnish has been
+commonly used. To 100 parts of pure linseed-oil are added 4 parts of
+litharge and 1 part of umber, and the mixture is heated to about 350°
+Fahr., for six or seven hours, and stirred constantly. After standing a
+few days the clear part is drawn off for use. For the thicker varnish
+used on later coats, the heat should be raised to 450° and kept at
+about that temperature until it becomes thick. This operation is
+attended with much danger of the oil taking fire, and should be done
+only by an experienced varnish-maker.
+
+The only advantages of the linseed-oil varnish are its ease of
+application, and its cheapness. Its drawbacks are stickiness--requiring
+continual examination of the balloon envelope, especially when the
+deflated bag is stored away--its liability to spontaneous combustion,
+particularly when the varnish is new, and its very slow drying
+qualities, requiring a long wait between the coats.
+
+Another varnish made by dissolving rubber in benzine, has been
+largely used. It requires vulcanizing after application. It is
+never sticky, and is always soft and pliable. However, the rubber
+is liable to decomposition from the action of the violet ray of
+light, and a balloon so varnished requires the protection of an outer
+yellow covering--either of paint, or an additional yellow fabric.
+Unfortunately, a single sheet of rubberized material is not gas-tight,
+and it is necessary to make the envelope of two, or even three, layers
+of the fabric, thus adding much to the weight.
+
+The great gas-bags of the Zeppelin airships are varnished with
+“Pegamoid,” a patent preparation the constituents of which are not
+known. Its use by Count Zeppelin is the highest recommendation possible.
+
+The weight of the varnish adds largely to the weight of the envelope.
+French pongee silk after receiving its five coats of linseed-oil
+varnish, weighs 8 ounces per square yard. A double bag of percale with
+a layer of vulcanized rubber between, and a coating of rubber on the
+inside, and painted yellow on the outside, will weigh 11 ounces per
+square yard. Pegamoid material, which comes ready prepared, weighs but
+about 4 ounces per square yard, but is much more costly.
+
+In cutting out the gores of the envelope it is possible to waste fully
+⅓ of the material unless the work is skilfully planned. Taking the
+width of the chosen material as a basis, we must first deduct from ¾
+of an inch to 1½ inches, in proportion to the size of the proposed
+balloon, for a broad seam and the overlapping necessary. Dividing the
+circumference at the largest diameter--the “equator” of the balloon--by
+the remaining width of the fabric gives the number of gores required.
+To obtain the breadth of each gore at the different “latitudes”
+(supposing the globe of the balloon to be divided by parallels
+similar to those of the earth) the following table is to be used; 0°
+representing the equator, and 90° the apex of the balloon. The breadth
+of the gore in inches at any latitude is the product of the decimal
+opposite that latitude in the table by the original width of the fabric
+in inches, thus allowing for seams.
+
+[Illustration:
+
+    Finsterwalder’s method of cutting material for a spherical
+    balloon, by which over one-fourth of the material, usually
+    wasted in the common method, may be saved. It has the further
+    advantage of saving more than half of the usual sewing. The
+    balloon is considered as a spherical hexahedron (a six-surfaced
+    figure similar to a cube, but with curved sides and edges). The
+    circumference of the sphere divided by the width of the material
+    gives the unit of measurement. The dimensions of the imagined
+    hexahedron may then be determined from the calculated surface
+    and the cutting proceed according to the illustration above,
+    which shows five breadths to each of the six curved sides. The
+    illustration shows the seams of the balloon made after the
+    Finsterwalder method, when looking down upon it from above.]
+
+
+TABLE FOR CALCULATING SHAPE OF GORES FOR SPHERICAL BALLOONS
+
+   0°  1.000
+   3°  0.998
+   6°  0.994
+   9°  0.988
+  12°  0.978
+  15°  0.966
+  18°  0.951
+  21°  0.934
+  24°  0.913
+  27°  0.891
+  30°  0.866
+  33°  0.839
+  36°  0.809
+  39°  0.777
+  42°  0.743
+  45°  0.707
+  48°  0.669
+  51°  0.629
+  54°  0.588
+  57°  0.544
+  60°  0.500
+  63°  0.454
+  66°  0.407
+  69°  0.358
+  72°  0.309
+  75°  0.259
+  78°  0.208
+  81°  0.156
+  84°  0.104
+  87°  0.052⅓
+
+In practice, the shape of the gore is calculated by the above table,
+and plotted out on a heavy pasteboard, generally in two sections for
+convenience in handling. The board is cut to the plotted shape and used
+as the pattern for every gore. In large establishments all the gores
+are cut at once by a machine.
+
+The raw edges are hemmed, and folded into one another to give a flat
+seam, and are then sewn together “through and through,” in twos and
+threes: afterward these sections are sewn together. Puckering must be
+scrupulously avoided. In the case of rubberized material, the thread
+holes should be smeared with rubber solution, and narrow strips of the
+fabric cemented over the seams with the same substance.
+
+Varnishing is the next process, the gores being treated in turn.
+Half of the envelope is varnished first, and allowed to dry in a
+well-ventilated place out of reach of the sun’s rays. The other half is
+varnished when the first is dry. A framework which holds half of the
+balloon in the shape of a bell is usually employed. In case of haste,
+the balloon may be blown up with air, but this must be constantly
+renewed to be of any service.
+
+The first step in varnishing is to get one side (the outer, or the
+inner) coated with a varnish thin enough to penetrate the material:
+then turn the envelope the other side out and give that a coat of the
+thin varnish. Next, after all is thoroughly dry, give the outer side
+a coat of thick varnish closing all pores. When this is dry give the
+inner side a similar coat. Finally, after drying thoroughly, give
+both sides a coat of olive oil to prevent stickiness. The amount of
+varnish required is, for the first coat 1½ times the weight of the
+envelope, and for the second coat ½ the weight--of the thin varnish.
+For the thick coat on the outer side ⅓ of the weight of the envelope,
+and on the inner side about half as much. For the olive-oil coat, about
+⅛ of the weight of the envelope will be needed. These figures are
+approximate, some material requiring more, some less; and a wasteful
+workman will cause a greater difference.
+
+The neck of the balloon (also called the tail) is in form a cylindrical
+tube of the fabric, sewn to an opening in the bottom of the balloon,
+which has been strengthened by an extra ring of fabric to support it.
+The lower end of the tube, called the mouth, is sewn to a wooden ring,
+which stiffens it. The size of the neck is dependent upon the size of
+the balloon. Its diameter is determined by finding the cube of one-half
+the diameter of the balloon, and dividing it by 1,000. In length, the
+neck should be at least four times its diameter.
+
+The apex of the balloon envelope is fitted with a large valve to permit
+the escape of gas when it is desired that the balloon shall descend.
+The door of the valve is made to open inward into the envelope, and
+is pulled open by the valve-cord which passes through the neck of the
+balloon into the basket, or car. This valve is called the manœuvring
+valve, and there are many different designs equally efficient. As they
+may be had ready made, it is best for the amateur, unless he is a
+machinist, to purchase one. The main point to see to is that the seat
+of the valve is of soft pliable rubber, and that the door of the valve
+presses a comparatively sharp edge of metal or wood so firmly upon the
+seat as to indent it; and the springs of the valve should be strong
+enough to hold it evenly to its place.
+
+The making of the net of the balloon is another part of the work which
+must be delegated to professionals. The material point is that the net
+distributes the weight evenly over the surface of the upper hemisphere
+of the envelope. The strength of the cordage is an item which must be
+carefully tested. Different samples of the same material show such wide
+variations in strength that nothing but an actual test will determine.
+In general, however, it may be said that China-grass cordage is four
+times as strong as hemp cordage, and silk cordage is ten times as
+strong as hemp--for the same size cords.
+
+The meshes of the net should be small, allowing the use of a small
+cord. Large cords mean large knots, and these wear seriously upon the
+balloon envelope, and are very likely to cause leaks. In large meshes,
+also, the envelope puffs out between the cords and becomes somewhat
+stretched, opening pores through which much gas is lost by diffusion.
+
+The “star,” or centre of the net at the apex of the balloon, must be
+fastened immovably to the rim of the valve. The suspension cords begin
+at from 30° to 45° below the equator of the envelope, and are looped
+through rings in what are called “goose-necks.” These allow a measure
+of sliding motion to the cordage as the basket sways in the wind.
+
+For protecting the net against rotting from frequent wetting, it is
+recommended to saturate it thoroughly with a solution of acetate of
+soda, drying immediately. Paraffin is sometimes used with more or less
+success, but tarring should be avoided, as it materially weakens the
+cordage. Oil or grease are even worse.
+
+At the bottom of the net proper the few large cords into which the many
+small cords have been merged are attached to the ring of the balloon.
+This is either of steel or of several layers of wood well bound
+together. The ropes supporting the basket are also fastened to this
+ring, and from it hang the trail-rope and the holding ropes.
+
+[Illustration:
+
+    Sketch showing the diamond mesh of balloon cordage and the method
+    of distributing the rings for the goose-necks; also the merging
+    of netting cords into the suspension cords which support the car.
+    The principal knots used in tying balloon nets are shown on the
+    right.]
+
+The basket is also to be made by a professional, as upon its
+workmanship may depend the lives of its occupants, though every other
+feature of the balloon be faultless. It must be light, and still very
+strong to carry its load and withstand severe bumping. It should be
+from 3 to 4 feet deep, with a floor space of 4 feet by 5 feet. It is
+usually made of willow and rattan woven substantially together. The
+ropes supporting the car are passed through the bottom and woven in
+with it. Buffers are woven on to the outside, and the inside is padded.
+The seats are small baskets in which is stored the equipment. With
+the completion of these the balloon is ready for its furnishings and
+equipment, which come under the direction of the pilot, or captain, as
+detailed in the preceding chapter.
+
+
+
+
+Chapter XVII.
+
+MILITARY AERONAUTICS.
+
+    The pioneer Meusnier--L’Entreprenant--First aerostiers--First
+    aerial warship--Bombardment by balloons--Free balloons
+    in observations--Ordering artillery from balloon--The
+    postal balloons of Paris--Compressed hydrogen--National
+    experiments--Bomb dropping--Falling explosives--Widespread
+    activity in gathering fleets--Controversies--Range of
+    vision--Reassuring outlook.
+
+
+Almost from the beginning of success in traversing the air the great
+possibilities of all forms of aircraft as aids in warfare have been
+recognized by military authorities, and, as has so often been the case
+with other inventions by non-military minds, the practically unlimited
+funds at the disposal of national war departments have been available
+for the development of the balloon at first, then the airship, and now
+of the aeroplane.
+
+The Montgolfiers had scarcely proved the possibility of rising into
+the air, in 1783, before General Meusnier was busily engaged in
+inventing improvements in their balloon with the expressed purpose of
+making it of service to his army, and before he was killed in battle
+he had secured the appointment of a commission to test the improved
+balloon as to its efficiency in war. The report of the committee
+being favorable, a balloon corps was formed in April, 1794, and the
+balloon _L’Entreprenant_ was used during the battle of Fleurus, on
+June 26th, by Meusnier’s successor, General Jourdan, less than a year
+after Meusnier’s death. In 1795 this balloon was used in the battle of
+Mayence. In both instances it was employed for observation only.
+
+But when the French entered Moscow, they found there, and captured, a
+balloon laden with 1,000 pounds of gunpowder which was intended to have
+been used against them.
+
+In 1796 two other balloons were used by the French army then in front
+of Andernach and Ehrenbreitstein, and in 1798 the 1st Company of
+Aerostiers was sent to Egypt, and operated at the battle of the Nile,
+and later at Cairo. In the year following, this balloon corps was
+disbanded.
+
+In 1812 Russia secured the services of a German balloon builder named
+Leppich, or Leppig, to build a war balloon. It had the form of a
+fish, and was so large that the inflation required five days, but the
+construction of the framework was faulty, and some important parts
+gave way during inflation, and the airship never left the ground. As it
+was intended that this balloon should be dirigible and supplied with
+explosives, and take an active part in attacks on enemies, it may be
+regarded as the first aerial warship.
+
+[Illustration: A military dirigible making a tour of observation.]
+
+In 1849, however, the first actual employment of the balloon in warfare
+took place. Austria was engaged in the bombardment of Venice, and the
+range of the besieging batteries was not great enough to permit shells
+to be dropped into the city. The engineers formed a balloon detachment,
+and made a number of Montgolfiers out of paper. These were of a size
+sufficient to carry bombs weighing 30 pounds for half an hour before
+coming down. These war balloons were taken to the windward side of
+the city, and after a pilot balloon had been floated over the point
+where the bombs were to fall, and the time consumed in the flight
+ascertained, the fuses of the bombs were set for the same time, and
+the war balloons were released. The actual damage done by the dropping
+of these bombs was not great, but the moral effect upon the people of
+the city was enormous. The balloon detachment changed its position as
+the wind changed, and many shells were exploded in the heart of the
+city, one of them in the market place. But the destruction wrought was
+insignificant as compared with that usually resulting from cannonading.
+As these little Montgolfiers were sent up unmanned, perhaps they are
+not strictly entitled to be dignified by the name of war balloon, being
+only what in this day would be called aerial bombs.
+
+The next use of the balloon in warfare was by Napoleon III, in 1859.
+He sent up Lieutenant Godard, formerly a manufacturer of balloons, and
+Nadar, the balloonist, at Castiglione. It was a tour of observation
+only, and Godard made the important discovery that the inhabitants were
+gathering their flocks of domestic animals and choking the roads with
+them, to oppose the advance of the French.
+
+The first military use of balloons in the United States was at the time
+of the Civil War. Within a month after the war broke out, Professor T.
+S. C. Lowe, of Washington, put himself and his balloon at the command
+of President Lincoln, and on June 18, 1861, he sent to the President a
+telegram from the balloon--the first record of the kind in history.
+
+After the defeat at Manassas, on July 24, 1861, Professor Lowe made a
+free ascent, and discovered the true position of the Confederates, and
+proved the falsity of rumors of their advance. The organization of
+a regular balloon corps followed, and it was attached to McClellan’s
+army, and used in reconnoitering before Yorktown. The balloons were
+operated under heavy artillery fire, but were not injured.
+
+[Illustration: A small captive military balloon fitted for observation.
+A cylinder of compressed hydrogen to replace leakage is seen at F.]
+
+On May 24th, for the first time in history, a general officer--in this
+case, General Stoneman--directed the fire of artillery at a hidden
+enemy from a balloon.
+
+Later in the month balloons were used at Chickahominy, and again at
+Fair Oaks and Richmond, being towed about by locomotives. On the
+retreat from before Richmond, McClellan’s balloons and gas generators
+were captured and destroyed.
+
+In 1869, during the siege of a fort at Wakamatzu by the Imperial
+Japanese troops, the besieged sent up a man-carrying kite. After making
+observations, the officer ascended again with explosives, with which he
+attempted to disperse the besieging army, but without success.
+
+During the siege of Paris, in 1870, there were several experienced
+balloonists shut up in the city, and the six balloons at hand were
+quickly repaired and put to use by the army for carrying dispatches
+and mail beyond the besieging lines. The first trips were made by
+the professional aeronauts, but, as they could not return, there was
+soon a scarcity of pilots. Sailors, and acrobats from the Hippodrome,
+were pressed into the service, and before the siege was raised 64 of
+these postal balloons had been dispatched. Fifty-seven out of the 64
+landed safely on French territory, and fulfilled their mission; 4
+were captured by the Germans; 1 floated to Norway; 1 was lost, with
+its crew of two sailors, who faithfully dropped their dispatches on
+the rocks near the Lizard as they were swept out to sea; and 1 landed
+on the islet Hoedic, in the Atlantic. In all, 164 persons left Paris
+in these balloons, always at night, and there were carried a total of
+9 tons of dispatches and 3,000,000 letters. At first dogs were carried
+to bring back replies, but none ever returned. Then carrier pigeons
+were used successfully. Replies were set in type and printed. These
+printed sheets were reduced by photography so that 16 folio pages of
+print, containing 32,000 words, were reduced to a space of 2 inches
+by 1¼ inches on the thinnest of gelatine film. Twenty of these films
+were packed in a quill, and constituted the load for each pigeon. When
+received in Paris, the films were enlarged by means of a magic lantern,
+copied, and delivered to the persons addressed.
+
+[Illustration:
+
+    Spherical canister of compressed hydrogen for use in inflating
+    military balloons. A large number of these canisters may be
+    tapped at the same time and the inflation proceed rapidly; a
+    large balloon being filled in two hours.]
+
+In more recent times the French used balloons at Tonkin, in 1884; the
+English, in Africa, in 1885; the Italians, in Abyssinia, in 1888; and
+the United States, at Santiago, in 1898. During the Boer War, in 1900,
+balloons were used by the British for directing artillery fire, and
+one was shot to pieces by well-aimed Boer cannon. At Port Arthur, both
+the Japanese and the Russians used balloons and man-carrying kites for
+observation. The most recent use is that by Spain, in her campaign
+against the Moors, in 1909.
+
+The introduction of compressed hydrogen in compact cylinders, which are
+easily transported, has simplified the problem of inflating balloons in
+the field, and of restoring gas lost by leakage.
+
+The advent of the dirigible has engaged the active attention of the
+war departments of all the civilized nations, and experiments are
+constantly progressing, in many instances in secret. It is a fact
+at once significant and interesting, as marking the rapidity of the
+march of improvement, that the German Government has lately refused
+to buy the newest Zeppelin dirigible, on the ground that it is built
+of aluminum, which is out of date since the discovery of its lighter
+alloys.
+
+[Illustration: The German military non-rigid dirigible Parseval II. It
+survived the storm which wrecked the Zeppelin II in April, 1910, and
+reached its shed at Cologne in safety.]
+
+Practically all the armies are being provided with fleets of
+aeroplanes, ostensibly for use in scouting. But there have been many
+contests by aviators in “bomb-dropping” which have at least proved
+that it is possible to drop explosives from an aeroplane with a great
+degree of accuracy. The favorite target in these contests has been
+the life-sized outline of a battleship.
+
+[Illustration: The German military Zeppelin dirigible, which took part
+in the manœuvres at Hamburg in April, 1910, and was wrecked by a high
+wind at Weilburg on the return journey to Cologne.]
+
+Glenn Curtiss, after his trip down the Hudson from Albany, declared
+that he could have dropped a large enough torpedo upon the Poughkeepsie
+Bridge to have wrecked it. His subsequent feats in dropping “bombs,”
+represented by oranges, have given weight to his claims.
+
+By some writers it is asserted that the successful navigation of the
+air will guarantee universal peace; that war with aircraft will be so
+destructive that the whole world will rise against its horrors. Against
+a fleet of flying machines dropping explosives into the heart of great
+cities there can be no adequate defence.
+
+On the other hand, Mr. Hudson Maxim declares that the exploding of
+the limited quantities of dynamite that can be carried on the present
+types of aeroplanes, on the decks of warships would not do any vital
+damage. He also says that many tons of dynamite might be exploded in
+Madison Square, New York City, with no more serious results than the
+blowing out of the windows of the adjacent buildings as the air within
+rushed out to fill the void caused by the uprush of air heated by the
+explosion.
+
+[Illustration: The Lebaudy airship “La Patrie.” As compared with the
+first Lebaudy, it shows the rounded stern with stabilizing planes, and
+the long fin beneath, with rudder and dipping planes.]
+
+As yet, the only experience that may be instanced is that of the
+Russo-Japanese War, where cast-iron shells, weighing 448 lbs.,
+containing 28 lbs. of powder, were fired from a high angle into Port
+Arthur, and did but little damage.
+
+In 1899 the Hague Conference passed a resolution prohibiting the use of
+aircraft to discharge projectiles or explosives, and limited their use
+in war to observation. Germany, France, and Italy withheld consent upon
+the proposition.
+
+In general, undefended places are regarded as exempt from attack by
+bombardment of any kind.
+
+Nevertheless, there are straws which show how the wind is blowing.
+German citizens and clubs which purchase a type of airship approved
+by the War Office of the German Empire are to receive a substantial
+subsidy, with the understanding that in case of war the aircraft is to
+be at the disposal of the Government. Under this plan it is expected
+that the German Government will control a large fleet of ships of the
+air without being obliged to own them.
+
+And, in France, funds were raised recently, by popular subscription,
+sufficient to provide the nation with a fleet of fourteen airships
+(dirigibles) and thirty aeroplanes. These are already being built,
+and it will not be long before France will have the largest air-fleet
+afloat.
+
+The results of the German manœuvres with a fleet of four dirigibles in
+a night attack upon strong fortresses have been kept a profound secret,
+as if of great value to the War Office.
+
+In the United States the Signal Corps has been active in operating the
+Baldwin dirigible and the Wright aeroplanes owned by the Government.
+To the latter, wireless telegraphic apparatus has been attached and is
+operated successfully when the machines are in flight. In addition,
+the United States Aeronautical Reserve has been formed, with a large
+membership of prominent amateur and professional aviators.
+
+Some military experts, however, assert that the dirigible is hopelessly
+outclassed for warfare by the aeroplane, which can operate in winds
+in which the dirigible dare not venture, and can soar so high above
+any altitude that the dirigible can reach as to easily destroy it.
+Another argument used against the availability of the dirigible as a
+war-vessel is, that if it were launched on a wind which carried it over
+the enemy’s country, it might not be able to return at sufficient speed
+to escape destruction by high-firing guns, even if its limited fuel
+capacity did not force a landing.
+
+Even the observation value of the aircraft is in some dispute. The
+following table is quoted as giving the ranges possible to an observer
+in the air:
+
+
+  Altitude in feet.  Distance of horizon.
+
+    500                30 miles.
+  1,000                42   “
+  2,000                59   “
+  3,000                72   “
+  4,000                84   “
+  5,000                93   “
+
+As a matter of fact, the moisture ordinarily in the air effectually
+limits the range of both natural vision and the use of the camera for
+photographing objects on the ground. The usual limit of practical range
+of the best telescope is eight miles.
+
+All things considered, however, it is to be expected that the
+experimenting by army and navy officers all over the world will lead to
+such improvement and invention in the art of navigating the air as will
+develop its benevolent, rather than its malevolent, possibilities--“a
+consummation devoutly to be wished.”
+
+
+
+
+Chapter XVIII.
+
+BIOGRAPHIES OF PROMINENT AERONAUTS.
+
+    The Wright Brothers--Santos-Dumont--Louis Bleriot--Gabriel
+    Voisin--Leon Delagrange--Henri Farman--Robert
+    Esnault-Pelterie--Count von Zeppelin--Glenn H. Curtiss--Charles
+    K. Hamilton--Hubert Latham--Alfred Leblanc--Claude
+    Grahame-White--Louis Paulhan--Clifford B. Harmon--Walter
+    Brookins--John B. Moisant--J. Armstrong Drexel--Ralph Johnstone.
+
+
+On January 1, 1909, it would have been a brief task to write a few
+biographical notes about the “prominent” aviators. At that date
+there were but five who had made flights exceeding ten minutes in
+duration--the Wright brothers, Farman, Delagrange, and Bleriot. At the
+close of 1910 the roll of aviators who have distinguished themselves by
+winning prizes or breaking previous records has increased to more than
+100, and the number of qualified pilots of flying machines now numbers
+over 300. The impossibility of giving even a mention of the notable
+airmen in this chapter is apparent, and the few whose names have been
+selected are those who have more recently in our own country come into
+larger public notice, and those of the pioneers whose names will never
+lose their first prominence.
+
+
+THE WRIGHT BROTHERS.
+
+The Wright Brothers have so systematically linked their individual
+personalities in all their work, in private no less than in public,
+that the brief life story to be told here is but one for them both. In
+fact, until Wilbur went to France in 1908, and Orville to Washington,
+the nearest approach to a separation is illustrated by a historic
+remark of Wilbur’s to an acquaintance in Dayton, one afternoon:
+“Orville flew 21 miles yesterday; I am going to beat that to-day.” And
+he did--by 3 miles.
+
+Their early life in their home town of Dayton, Ohio, was unmarked by
+significant incident. They were interested in bicycles, and at length
+went into the business of repairing and selling these machines.
+
+Their attention seems to have been strongly turned to the subject of
+human flight by the death of Lilienthal in August, 1896, at which time
+the press published some of the results of his experiments. A magazine
+article by Octave Chanute, himself an experimenter with gliders, led
+to correspondence with him, and the Wrights began a series of similar
+investigations with models of their own building.
+
+By 1900 they had succeeded in flying a large glider by running with a
+string, as with a kite, and in the following year they had made some
+flights on their gliders, of which they had several of differing types.
+For two years the Wrights studied and tested and disproved nearly every
+formula laid down by scientific works for the relations of gravity to
+air, and finally gave themselves up to discovering by actual trial
+what the true conditions were, and to the improvement of their gliders
+accordingly. Meanwhile they continued their constant personal practice
+in the air.
+
+The most of this experimental work was done at Kitty Hawk, N. C.; for
+the reason that there the winds blow more uniformly than at any other
+place in the United States, and the great sand dunes there gave the
+Wrights the needed elevation from which to leap into the wind with
+their gliders. Consequently, when at last they were ready to try a
+machine driven by a motor, it was at this secluded spot that the first
+flights ever made by man with a heavier-than-air machine took place. On
+December 17, 1903, their first machine left the ground under its own
+power, and remained in the air for twelve seconds. From this time on
+progress was even slower than before, on account of the complications
+added by the motive power; but by the time another year had passed they
+were making flights which lasted five minutes, and had their machine in
+such control that they could fly in a circle and make a safe landing
+within a few feet of the spot designated.
+
+[Illustration: Turpin, Taylor, Orville Wright, Wilbur Wright, Brookins,
+and Johnstone discussing the merits of the Wright machine.]
+
+On the 5th of October, 1905, Wilbur Wright made his historic flight
+of 24 miles at Dayton, Ohio, beating the record of Orville, made the
+day before, of 21 miles. The average speed of these flights was 38
+miles an hour. No contention as to the priority of the device known
+as wing-warping can ever set aside the fact that these long practical
+flights were made more than a year before any other man had flown 500
+feet, or had remained in the air half a minute, with a heavier-than-air
+machine driven by power.
+
+The Wrights are now at the head of one of the largest aeroplane
+manufactories in the world, and devote the larger part of their time to
+research work in the line of the navigation of the air.
+
+
+ALBERTO SANTOS-DUMONT.
+
+ALBERTO SANTOS-DUMONT was born in Brazil in 1877. When but a lad he
+became intensely interested in aeronautics, having been aroused by
+witnessing the ascension at a show of an ordinary hot-air balloon.
+Within the next few years he had made several trips to Paris, and
+in 1897 made his first ascent in a balloon with the balloon builder
+Machuron, the partner of the famous Lachambre.
+
+In 1898 he began the construction of his notable series of dirigibles,
+which eventually reached twelve in number. With his No. 6 he won the
+$20,000 prize offered by M. Deutsch (de la Meurthe) for the first trip
+from the Paris Aero Club’s grounds to and around the Eiffel Tower in 30
+minutes or less. The distance was nearly 7 miles. It is characteristic
+of M. Santos-Dumont that he should give $15,000 of the prize to relieve
+distress among the poor of Paris, and the remainder to his mechanicians
+who had built the balloon.
+
+His smallest dirigible was the No. 9, which held 7,770 cubic feet of
+gas; the largest was the No. 10, which held 80,000 cubic feet.
+
+In 1905, when Bleriot, Voisin, and their comrades were striving to
+accomplish flight with machines heavier than air, Santos-Dumont turned
+his genius upon the same problem, and on August 14, 1906, he made
+his first flight with a cellular biplane driven by a 24 horse-power
+motor. On November 13th of the same year he flew 720 feet with the same
+machine. These were the first flights of heavier-than-air machines in
+Europe, and the first public flights anywhere. Later he turned to the
+monoplane type, and with “La Demoiselle” added new laurels to those
+already won with his dirigibles.
+
+
+LOUIS BLERIOT.
+
+LOUIS BLERIOT, designer and builder of the celebrated Bleriot
+monoplanes, and himself a pilot of the first rank, was born in Cambrai,
+France, in 1872. He graduated from a noted technical school, and soon
+attached himself to the group of young men--all under thirty years of
+age--who were experimenting with gliders in the effort to fly. His
+attempts at first were with the flapping-wing contrivances, but he soon
+gave these up as a failure, and devoted his energy to the automobile
+industry; and the excellent Bleriot acetylene headlight testifies to
+his constructive ability in that field.
+
+Attracted by the experiments of M. Ernest Archdeacon he joined his
+following, and with Gabriel Voisin engaged in building gliders of the
+biplane type. By 1907 he had turned wholly to the monoplane idea,
+and in April of that year made his first leap into the air with a
+power-driven monoplane. By September he had so improved his machine
+that he was able to fly 600 feet, and in June, 1908, he broke the
+record for monoplanes by flying nearly a mile. Again and again he beat
+his own records, and at length the whole civilized world was thrilled
+by his triumphant flight across the British Channel on July 25, 1909.
+
+The Bleriot machines hold nearly all the speed records, and many of
+those in other lines of achievement, and M. Bleriot enjoys the double
+honor of being an eminently successful manufacturer as well as a
+dauntless aviator of heroic rank.
+
+
+GABRIEL VOISIN.
+
+GABRIEL VOISIN, the elder of the two Voisin brothers, was born in
+1879 at Belleville-sur-Saone, near the city of Lyons, France. He was
+educated as an architect, but early became interested in aeronautics,
+and engaged in gliding, stimulated by the achievements of Pilcher,
+in England, and Captain Ferber, in his own country. He assisted M.
+Archdeacon in his experiments on the Seine, often riding the gliders
+which were towed by the swift motor boats.
+
+In 1906 he associated himself with his brother in the business of
+manufacturing biplane machines, and in March, 1907, he himself made
+the first long flight with a power-driven machine in Europe. This
+aeroplane was built for his friend Delagrange, and was one in which
+the latter was soon breaking records and winning prizes. The second
+machine was for Farman, who made the Voisin biplane famous by winning
+the Deutsch-Archdeacon prize of $10,000 for making a flight of 1,093
+yards in a circle.
+
+The Voisin biplane is distinctive in structure, and is accounted one of
+the leading aeroplanes of the present day.
+
+
+LEON DELAGRANGE.
+
+LEON DELAGRANGE was born at Orleans, France, in 1873. He entered
+the School of Arts as a student in sculpture, about the same time
+that Henri Farman went there to study painting, and Gabriel Voisin,
+architecture. He exhibited at the Salon, and won several medals.
+In 1905, he took up aeronautics, assisted at the experiments of M.
+Archdeacon. His first aeroplane was built by Voisin, and he made his
+first flight at Issy, March 14, 1907. Less than a month later--on April
+11--he made a new record for duration of flight, remaining in the air
+for 9 minutes and 15 seconds--twice as long as the previous record made
+by Farman.
+
+[Illustration: Leblanc, Bleriot, and Delagrange, (from left to right)
+in aviation dress, standing in front of the Bleriot machine which
+crossed the English Channel.]
+
+At Rheims, in 1909, he appeared with a Bleriot monoplane, and continued
+to fly with that type of machine until his death. At Doncaster,
+England, he made the world record for speed up to that time, travelling
+at the rate of 49.9 miles per hour. He was killed at Bordeaux, France,
+in January, 1910, by the fall of his machine.
+
+
+HENRI FARMAN.
+
+HENRI FARMAN, justly regarded as the most prominent figure in the
+aviation world today, was born in France in 1873. His father was an
+Englishman.
+
+While a mere boy he became locally famous as a bicycle racer, and later
+achieved a wider fame as a fearless and skillful driver in automobile
+races. In 1902 he won the Paris-Vienna race.
+
+In September, 1907, he made his first attempt to fly, using the second
+biplane built by his friend Gabriel Voisin, and in the following
+year he won with it the Deutsch-Archdeacon prize of $10,000. He then
+built a machine after his own ideas, which more resembles the Wright
+machine than the Voisin, and with it he has won many prizes, and made
+many world records. Demands for machines, and for teaching the art of
+handling them, have poured in upon him, necessitating a continual
+increase of manufacturing facilities until it may safely be said that
+he has the largest plant for building flying machines in the world,
+turning out the largest number of machines, and through his school for
+aviators is instructing a larger number of pupils annually than any
+other similar establishment.
+
+
+ROBERT ESNAULT-PELTERIE.
+
+ROBERT ESNAULT-PELTERIE was born in 1880, and educated in the city of
+Paris. He early showed a mechanical turn of mind, and was interested
+particularly in scientific studies. He became an enthusiast in matters
+aeronautic, and devoted himself to the construction of gasoline engines
+suitable for aviation purposes. After satisfying his ideal in this
+direction with the now famous “R-E-P” motor, he designed a new type
+of flying machine which is known as the “R-E-P monoplane.” His first
+flights were made at Buc in October, 1907, and while they were short,
+they proved the possibility of steering a flying machine so that it
+would describe a curved line--at that time a considerable achievement
+among European aviators. In April, 1908, he flew for ¾ of a mile, and
+reached a height of 100 feet. This feat eclipsed all previous records
+for monoplanes.
+
+His fame, however, rests upon his motors, which are quite original in
+design and construction.
+
+
+COUNT FERDINAND VON ZEPPELIN.
+
+COUNT FERDINAND VON ZEPPELIN was born in 1838, on the shores of the
+Lake Constance, where his great airships have had their initial trials.
+
+It is an interesting fact that Count von Zeppelin made his first
+balloon ascension in a war-balloon attached to the army corps commanded
+by his friend, Carl Schurz, during the Civil War.
+
+It was only after years of absorbing study of all that human knowledge
+could contribute that Count von Zeppelin decided upon the type of
+dirigible which bears his name. Under the patronage of the King of
+Würtemberg he began his first airship, having previously built an
+immense floating shed, which, swinging by a cable, always had its doors
+facing away from the wind.
+
+The successful flights of the series of magnificent Zeppelin airships
+have been marvellous in an age crowded with wonders. And the misfortune
+which has followed close upon their superb achievements with complete
+destruction would long ago have undone a man of less energy and courage
+than the dauntless Count. It should be borne in mind, however, that
+of the hundreds of passengers carried in his ships of the air, all
+have come to land safely--a record that it would be difficult to match
+with any other form of travel. The accidents which have destroyed the
+Zeppelins have never happened in the air, excepting only the wrecking
+of the _Deutschland_ by a thunderstorm.
+
+The indefatigable Count is now constructing another airship with the
+new alloy, electron, instead of aluminum. He estimates that 5,000
+pounds’ weight can be saved in this way.
+
+
+CAPTAIN THOMAS S. BALDWIN.
+
+CAPTAIN THOMAS S. BALDWIN, balloonist and aviator, was born in
+Mississippi in 1855. His first aeronautical experience was as a
+parachute rider from a balloon in the air. He invented the parachute
+he used, and received for it a gold medal from the Balloon Society
+of Great Britain. Exhibiting this parachute, Captain Baldwin made an
+extensive tour of the civilized world.
+
+In 1892 he built his first airship, a combination of a balloon, a
+screw propeller, and a bicycle, the last to furnish the motive power.
+It was not until 1902, when be installed an automobile engine in his
+airship, that he succeeded in making it sail. It was not yet dirigible,
+however; but after two years of devising and experimenting, he sailed
+away from Oakland, Cal., on August 2, 1904, against the wind, and
+after a short voyage, turned and came back to his balloon-shed. From
+this time on he made several successful dirigibles, and in 1908 he met
+all the requirements of the United States Government for a military
+dirigible, and sold to it the only dirigible it possesses.
+
+He became interested in the experiments of Curtiss and McCurdy at
+Hammondsport, in 1908, and aided in building the remarkable series of
+biplanes with which record flights were made. The newer design, known
+as the Baldwin biplane, is unique in the pivoted balancing plane set
+upright above the upper plane, a device entirely distinct from the
+warping or other manipulation of horizontal surfaces for the purpose of
+restoring lateral balance.
+
+
+GLENN HAMMOND CURTISS.
+
+GLENN HAMMOND CURTISS was born at Hammondsport, N. Y., on the shore
+of Lake Keuka, in 1878. From boyhood he was a competitor and winner
+in all sorts of races where speed was the supreme test. By nature a
+mechanic, he became noted for his ingenious contrivances in this line,
+and built a series of extremely fast motor-cycles, with one of which he
+made the record of one mile in 26⅖ seconds, which still stands as the
+fastest mile ever made by man with any form of mechanism.
+
+Through the purchasing of one of his light engines by Captain Baldwin
+for his dirigible, Curtiss became interested in aeronautical matters,
+and soon built a glider with which he sailed down from the Hammondsport
+hills. The combination of his motor and the glider was the next step,
+and on July 4, 1908, he flew 1½ miles with the _June Bug_, winning the
+_Scientific American_ trophy.
+
+Learning that the United States was not to be represented at the Rheims
+meet in August, 1909, he hastily built a biplane and went there. He won
+the first prize for the course of 30 kilometres (18.6 miles), second
+prize for the course of 10 kilometres, the James Gordon Bennett cup,
+and the tenth prize in the contest for distance. From Rheims he went to
+Brescia, Italy, and there won the first prize for speed. In all these
+contests he was matching his biplane against monoplanes which were
+acknowledged to be a faster type than the biplane.
+
+On May 29, 1910, Mr. Curtiss made the first stated aeroplane tour to
+take place in this country, travelling from Albany to New York City,
+137 miles, with but one stop for fuel. With this flight he won a prize
+of $10,000.
+
+He has made many other notable flights and stands in the foremost rank
+of the active aviators. At the same time he is busily engaged in the
+manufacture of the Curtiss biplane and the Curtiss engine, both staple
+productions in their line.
+
+
+CHARLES KEENEY HAMILTON.
+
+CHARLES KEENEY HAMILTON is justly regarded as one of the most skilful
+of aviators. He was born in Connecticut in 1881, and showed his “bent”
+by making distressing, and often disastrous, leaps from high places
+with the family umbrella for a parachute.
+
+In 1904 he worked with Mr. Israel Ludlow, who at that time was
+experimenting with gliders of his own construction, and when Mr. Ludlow
+began towing them behind automobiles, Hamilton rode on the gliders and
+steered them. Later he became interested in ballooning, and made a
+tour of Japan with a small dirigible.
+
+[Illustration: Hamilton and Latham.]
+
+He early became famous in the aviation world by his spectacular
+glides from a great height. He has said that the first of these was
+unintentional, but his motor having stopped suddenly while he was high
+in the air, he had only the other alternative of falling vertically.
+The sensation of the swift gliding having pleased him, he does it
+frequently “for the fun of it.” These glides are made at so steep an
+angle that they have gained the distinctive name, “Hamilton dives.”
+
+Hamilton came most prominently before the public at large with his
+flight from Governor’s Island to Philadelphia and back, on June 13,
+1910. Following close upon Curtiss’s flight from Albany to New York, it
+was not only a record-breaking achievement, but helped to establish in
+this country the value of the aeroplane as a vehicle for place-to-place
+journeyings.
+
+
+HUBERT LATHAM.
+
+HUBERT LATHAM, the famous Antoinette pilot, is a graduate of Oxford.
+His father was a naturalized Frenchman.
+
+His first aeronautical experience was as companion to his cousin,
+Jacques Faure, the balloonist, on his famous trip from London to Paris
+in 6½ hours, the fastest time ever made between the two places until
+the Clement-Bayard dirigible surpassed it by a few minutes on October
+16, 1910.
+
+The Antoinette monoplane with which M. Latham has identified himself
+began with the ingenious engine of Levavasseur, which was speedily
+made use of for aeroplanes by Santos-Dumont, Bleriot, and Farman.
+Levavasseur also had ideas about aeroplanes, and persuaded some
+capitalists to back him in the enterprise. When it was done, no one
+could be found to fly it. Here M. Latham, a lieutenant of miners and
+sappers in the French army, stepped into the breach, and has made a
+name for himself and for the Antoinette machine in the forefront of the
+progress of aviation.
+
+After winning several contests he set out, on July 19, 1909, to cross
+the British Channel. After flying about half the distance he fell into
+the sea. Six days later Bleriot made the crossing successfully, and
+Latham made a second attempt on July 27th, and this time got within a
+mile of the Dover coast before he again came down in the water.
+
+He has shown unsurpassed daring and skill in flying in gales blowing
+at 40 miles per hour, a record which few other aviators have cared to
+rival.
+
+
+ALFRED LEBLANC.
+
+ALFRED LEBLANC, the champion cross-country flier of the world, was
+born in France in 1879. By profession he is a metallurgist. A friend
+of Bleriot, he became interested in monoplane flying, the more readily
+because he was already a skilled balloonist.
+
+At the time Bleriot made his historic flight across the British
+Channel, Leblanc preceded him, and, standing on the Dover shore,
+signalled Bleriot where to strike the land.
+
+He organized Bleriot’s school for aviators at Pau, and became its
+director. Its excellence is exhibited in the quality of its pupils;
+among them Chavez, Morane, and Aubrun.
+
+The achievement through which Leblanc is most widely known is his
+winning of the 489-mile race over the northern part of France in
+August, 1910, and with the victory the prize of $20,000 offered.
+
+
+CLAUDE GRAHAME-WHITE.
+
+CLAUDE GRAHAME-WHITE, the most famous of British aviators, learned to
+fly in France, under the tutelage of M. Bleriot, Having accomplished
+so much, he went to Mourmelon, the location of Farman’s establishment,
+and made himself equally proficient on the Farman biplane. While in
+France he taught many pupils, among them Armstrong Drexel. Returning
+to England, he opened a school for English aviators.
+
+He came into prominent public notice in his contest with Paulhan in the
+race from London to Manchester, and although Paulhan won the prize,
+Grahame-White received a full share of glory for his plucky persistence
+against discouraging mishaps.
+
+At the Boston-Harvard meet, in September, 1910, Grahame-White carried
+off nearly all the prizes, and in addition won for himself a large
+measure of personal popularity.
+
+On October 14th he flew from the Benning Race Track 6 miles away, over
+the Potomac River, around the dome of the Capitol, the Washington
+Monument, and over the course of Pennsylvania Avenue, up to the State,
+War, and Navy Department building, alighting accurately with his
+40-foot biplane in the 60-foot street. Having ended his “call,” he
+mounted his machine and rose skilfully into the air and returned to his
+starting point.
+
+At the Belmont Park meet, in October, Grahame-White captured the
+international speed prize with his 100-horse-power Bleriot monoplane,
+and finished second in the race around the Statue of Liberty, being
+beaten by only 43 seconds.
+
+
+LOUIS PAULHAN.
+
+LOUIS PAULHAN was, in January, 1909, a mechanic in Mourmelon, France,
+earning the good wages in that country of $15 per week. He became
+an aviator, making his first flight on July 10, 1909, of 1¼ miles.
+Five days later he flew over 40 miles, remaining in the air 1 hour
+17 minutes, and rising to an altitude of 357 feet, then the world’s
+record. He flew constantly in public through the remainder of 1909,
+winning many prizes and breaking and making records.
+
+In January, 1910, he was the most prominent aviator at the Los Angeles
+meet, and there made a new world’s record for altitude, 4,166 feet.
+
+Within the 13 months and 3 weeks (up to October 1, 1910) that he has
+been flying, he has won over $100,000 in prizes, besides receiving many
+handsome fees for other flights and for instruction to pupils.
+
+
+CLIFFORD B. HARMON.
+
+CLIFFORD B. HARMON has the double distinction of being not only the
+foremost amateur aviator of America, but his feats have also at times
+excelled those of the professional airmen. On July 2, 1910, Mr. Harmon
+made a continuous flight of more than 2 hours, breaking all American
+records, and this he held for several months.
+
+Mr. Harmon’s first experience in the air was as a balloonist, and in
+this capacity he held the duration record of 48 hours 26 minutes for a
+year. On this same voyage, at the St. Louis Centennial, he made a new
+record in America for altitude attained, 24,400 feet.
+
+At the Los Angeles aviation meet, in January, 1910, where he went with
+his balloon _New York_, he met Paulhan, and became his pupil. At that
+meet Paulhan made a new world’s record for altitude with a Farman
+biplane, and this machine Mr. Harmon bought, and brought to Mineola, L.
+I., where he practised assiduously, crowning his minor achievements by
+flying from there across Long Island Sound to Greenwich, Conn.
+
+At the Boston-Harvard aviation meet, in September, 1910, Mr. Harmon won
+every prize offered to amateur contestants.
+
+
+WALTER BROOKINS.
+
+WALTER BROOKINS is one of the youngest of noted aviators. He was born
+in Dayton, Ohio, in 1890, and went to school to Miss Katherine Wright,
+sister of the Wright brothers. Young Walter was greatly interested
+in the experiments made by the Wrights, and Orville one day promised
+him that when he grew up they would build a flying machine for him.
+Brookins appeared at Dayton in the early part of 1910, after several
+years’ absence, during which he had grown up, and demanded the promised
+flying machine. The Wrights met the demand, and developed Brookins into
+one of the most successful American aviators.
+
+Brookins’s first leap into prominence was at the Indianapolis meet,
+in June, 1910, where he made a new world’s record for altitude, 4,803
+feet. This being beaten soon after in Europe, by J. Armstrong Drexel,
+with 6,600 feet, Brookins attempted, at Atlantic City, in September, to
+excel Drexel’s record, and rose to a height of 6,175 feet, being forced
+to come down by the missing of his motor.
+
+On September 29, 1910, he left Chicago for Springfield, Ill. He made
+two stops on the way for repairs and fuel, and reached Springfield in
+7 hours 9 minutes elapsed time. His actual time in the air was 5 hours
+47 minutes. The air-line distance between the two cities is 187 miles,
+but as Brookins flew in the face of a wind blowing 10 miles an hour,
+he actually travelled 250 miles. During the journey Brookins made a new
+cross-country record for America in a continuous flight for 2 hours 38
+minutes.
+
+
+JOHN B. MOISANT.
+
+JOHN B. MOISANT is an architect of Chicago, born there of Spanish
+parentage in 1883. Becoming interested in aviation, he went to France
+in 1909, and began the construction of two aeroplanes, one of them
+entirely of metal. He started to learn to fly on a Bleriot machine, and
+one day took one of his mechanicians aboard and started for London. The
+mechanician had never before been up in an aeroplane. After battling
+with storms and repairing consequent accidents to his machine, Moisant
+landed his passenger in London three weeks after the start. It was
+the first trip between the two cities for an aeroplane carrying a
+passenger, and although Moisant failed to win the prize which had been
+offered for such a feat, he received a great ovation, and a special
+medal was struck for him.
+
+At the Belmont Park meet, in October, 1910, Moisant, after wrecking
+his own machine in a gale, climbed into Leblanc’s Bleriot, which had
+been secured for him but a few minutes before, and made the trip around
+the Statue of Liberty in New York Bay and returned to the Park in 34
+minutes 38 seconds. As the distance is over 34 miles, the speed was
+nearly a mile a minute. This feat won for him, and for America, the
+grand prize of the meet--$10,000.
+
+
+J. ARMSTRONG DREXEL.
+
+J. ARMSTRONG DREXEL is a native of Philadelphia. He was taught to
+fly a Bleriot machine at Pau by Grahame-White, and he has frequently
+surpassed his instructor in contests where both took part. At the
+English meets in 1910 he won many of the prizes, being excelled in this
+respect only by Leon Morane.
+
+At Lanark, Scotland, he established a new world’s record for altitude,
+6,600 feet. At the Belmont Park meet he passed his former record with
+an altitude of 7,185 feet, making this the American record, though it
+had been excelled in Europe. At Philadelphia, November 23, 1910, he
+reached an altitude of 9,970 feet, according to the recording barometer
+he carried, thus making a new world’s record. This record was disputed
+by the Aero Club, and it may be reduced. A millionaire, he flies for
+sheer love of the sport.
+
+
+RALPH JOHNSTONE.
+
+RALPH JOHNSTONE was born in Kansas City, Mo., in 1880. He became an
+expert bicycle rider, and travelled extensively in many countries
+giving exhibitions of trick bicycle riding, including the feat known
+as “looping the loop.” He joined the staff of the Wright Brothers’
+aviators in April, 1910, and speedily became one of the most skilful
+aeroplane operators.
+
+He made a specialty of altitude flying, breaking his former records day
+after day, and finally, at the International Aviation Meet at Belmont
+Park, L. I., in October, 1910, he made a new world’s altitude record
+of 9,714 feet, surpassing the previous record of 9,121 feet made by
+Wynmalen at Mourmelon, on October 1st.
+
+Johnstone was instantly killed at Denver, Col., on November 14, 1910,
+by a fall with his machine owing to the breaking of one of the wings at
+a height of 800 feet.
+
+
+
+
+Chapter XIX.
+
+CHRONICLE OF AVIATION ACHIEVEMENTS.
+
+
+How feeble the start, and how wondrously rapid the growth of the art
+of flying! Nothing can better convey a full idea of its beginnings
+and its progress than the recorded facts as given below. And these
+facts show beyond dispute that the credit of laying the foundation for
+every accomplishment in the entire record must be largely due to the
+men whose names stand alone for years as the only aeroplanists in the
+world--the Wright Brothers.
+
+After the first flight on December 17, 1903, the Wrights worked
+steadily toward improving their machines, and gaining a higher degree
+of the art of balancing, without which even the most perfect machines
+would be useless. Most of their experimenting having been done in
+secret, the open record of their results from time to time is very
+meagre. It may be noted, however, that for nearly three years no one
+else made any records at all.
+
+The next name to appear on the roll is that of Santos-Dumont, already
+famous for his remarkable achievements in building and navigating
+dirigible balloons, or airships. His first aeroplane flight was on
+August 22, 1906, and was but little more than rising clear of the
+ground.
+
+It was nearly seven months later when Delagrange added his name to the
+three then on the list of practical aviators. In about five months
+Bleriot joined them, and in a few more weeks Farman had placed his name
+on the roll. It is interesting to compare the insignificant figures of
+the first flights of these men with their successive feats as they gain
+in experience.
+
+Up to October 19, 1907, the flights recorded had been made with
+machines of the biplane type, but on that date, R. Esnault-Pelterie
+made a few short flights with a monoplane. A month later Santos-Dumont
+had gone over to the monoplane type, and the little group of seven had
+been divided into two classes--five biplanists and two monoplanists.
+
+On March 29, 1908, Delagrange started a new column in the record book
+by taking a passenger up with him, in this case, Farman. They flew only
+453 feet, but it was the beginning of passenger carrying.
+
+During the first six months of 1908 only two more names were added to
+the roll--Baldwin and McCurdy--both on the biplane side. On July 4,
+1908, Curtiss comes into the circle with his first recorded flight,
+in which he used a biplane of his own construction. The same day in
+France, Bleriot changed to the ranks of the monoplane men, with a
+flight measured in miles, instead of in feet. Two days later, Farman
+advanced his distance record from 1.24 miles to 12.2 miles, and his
+speed record from about 21 miles an hour to nearly 39 miles an hour. In
+two days more, Delagrange had taken up the first woman passenger ever
+carried on an aeroplane; and a month later, Captain L. F. Ferber had
+made his first flights in public, and added his name to the growing
+legion of the biplanists.
+
+In the latter part of 1908, the Wrights seem to take possession of the
+record--Orville in America, and Wilbur in Europe--surpassing their own
+previous feats as well as those of others. Bleriot and Farman also
+steadily advance their performances to a more distinguished level.
+
+The record for 1909 starts off with three new names--Moore-Brabazon,
+and Legagneux in France, and Cody in England. Richardson, Count de
+Lambert, Calderara, Latham, Tissandier, Rougier, join the ranks of the
+aviators before the year is half gone, and a few days later Sommer and
+Paulhan add their names.
+
+Of these only Latham flies the monoplane type of machine, but at the
+Rheims tournament Delagrange appears as a monoplanist, increasing the
+little group to four; but, with Le Blon added later, they perform some
+of the most remarkable feats on record.
+
+The contest at Rheims in August is a succession of record-breaking and
+record-making achievements. But it is at Blackpool and Doncaster that
+the most distinct progress of the year is marked, by the daring flights
+of Le Blon and Latham in fierce gales. Spectators openly charged these
+men with foolhardiness, but it was of the first importance that it
+should be demonstrated that these delicately built machines can be
+handled safely in the most turbulent weather; and the fact that it has
+been done successfully will inspire every other aviator with a greater
+degree of confidence in his ability to control his machine in whatever
+untoward circumstances he may be placed. And such confidence is by far
+the largest element in safe and successful flying.
+
+
+NOTABLE AVIATION RECORDS TO CLOSE OF 1910
+
+    _December 17, 1903_--Wilbur Wright with biplane, at Kitty
+    Hawk, N. C., makes the first successful flight by man with
+    power-propelled machine, a distance of 852 feet, in 59 seconds.
+
+    _November 9, 1904_--Wilbur Wright with biplane, at Dayton, O.,
+    flies 3 miles in 4 minutes and 30 seconds. (He and Orville made
+    upward of 100 unrecorded flights in that year.)
+
+    _September 26, 1905_--Wilbur Wright with biplane “White Flier,”
+    at Dayton, O., flies 11 miles in 18 minutes and 9 seconds.
+
+    _September 29, 1905_--Orville Wright, with “White Flier,” at
+    Dayton, O., flies 12 miles in 19 minutes and 55 seconds.
+
+    _October 3, 1905_--Wilbur Wright, with “White Flier” at Dayton,
+    O., flies 15 miles in 25 minutes and 5 seconds.
+
+    _October 4, 1905_--Orville Wright with biplane “White Flier,” at
+    Dayton, O., flies 21 miles in 33 minutes and 17 seconds.
+
+    _October 5, 1905_--Wilbur Wright with “White Flier,” at Dayton,
+    O., flies 24 miles in 38 minutes. (He made many unrecorded
+    flights in that year.)
+
+    _August 22, 1906_--A. Santos-Dumont with biplane at Bagatelle,
+    France, made his first public flight with an aeroplane, hardly
+    more than rising clear of the ground.
+
+    _September 14, 1906_--Santos-Dumont with biplane, at Bagatelle,
+    flies for 8 seconds.
+
+[Illustration: Santos-Dumont flying at Bagatelle in his cellular
+biplane.]
+
+    _October 24, 1906_--Santos-Dumont with biplane, at Bagatelle,
+    flies 160 feet in 4 seconds.
+
+    _November 13, 1906_--Santos-Dumont with biplane, at Bagatelle,
+    flies 722 feet in 21 seconds. This feat is recorded as the first
+    aeroplane flight made in Europe.
+
+    _March 16, 1907_--Leon Delagrange with first Voisin biplane, at
+    Bagatelle, flies 30 feet.
+
+    _August 6, 1907_--Louis Bleriot with a Langley machine, at Issy,
+    France, flies 470 feet.
+
+    _October 15, 1907_--Henry Farman with biplane, at Issy, flies 937
+    feet in 21 seconds.
+
+    _October 19, 1907_--R. Esnault-Pelterie with monoplane, at Buc,
+    France, makes short flights.
+
+    _October 26, 1907_--Farman with biplane, at Issy, flies 2,529
+    feet in a half circle, in 52 seconds.
+
+    _November 17, 1907_--Santos-Dumont with biplane, at Issy, makes
+    several short flights, the longest being about 500 feet.
+
+    _November 21, 1907_--Santos-Dumont with monoplane at Bagatelle,
+    makes several short flights, the longest being about 400 feet.
+
+    _January 13, 1908_--Farman with biplane, at Issy, makes the
+    first flight in a circular course--3,279 feet in 1 minute and 28
+    seconds.
+
+    _March 12, 1908_--F. W. Baldwin with biplane “Red Wing,” at
+    Hammondsport, N. Y., flies 319 feet.
+
+    _March 21, 1908_--Farman with biplane, at Issy, flies 1.24 miles
+    in 3 minutes and 31 seconds.
+
+    _March 29, 1908_--Delagrange with biplane, at Ghent, Belgium,
+    makes first recorded flight with one passenger (Farman), 453 feet.
+
+    _April 11, 1908_--Delagrange with biplane at Issy, flies 2.43
+    miles in 6 minutes and 30 seconds, winning the Archdeacon cup.
+
+    _May 18, 1908_--J. A. D. McCurdy with biplane “White Wing” at
+    Hammondsport, flies 600 feet.
+
+    _May 27, 1908_--Delagrange with biplane, at Rome, in the presence
+    of the King of Italy, flies 7.9 miles in 15 minutes and 25
+    seconds.
+
+[Illustration: The early Voisin biplane flown by Farman at Issy.]
+
+    _May 30, 1908_--Farman with biplane, at Ghent, flies 0.77 miles
+    with one passenger (Mr. Archdeacon).
+
+    _June 8, 1908_--Esnault-Pelterie with monoplane, at Buc, flies
+    0.75 miles, reaching an altitude of 100 feet.
+
+    _June 22, 1908_--Delagrange with biplane, at Milan, Italy, flies
+    10.5 miles in 16 minutes and 30 seconds.
+
+    _July 4, 1908_--Glenn H. Curtiss with biplane, at Hammondsport,
+    flies 5,090 feet, in 1 minute and 42 seconds, winning _Scientific
+    American_ cup.
+
+[Illustration: The “June Bug” flown by Curtiss winning the _Scientific
+American_ cup, July 4, 1908.]
+
+    _July 4, 1908_--Bleriot with monoplane, at Issy, flies 3.7 miles
+    in 5 minutes and 47 seconds, making several circles.
+
+    _July 6, 1908_--Farman in biplane, at Ghent, flies 12.2 miles in
+    19 minutes and 3 seconds, winning the Armengand prize.
+
+    _July 8, 1908_--Delagrange with biplane, at Turin, Italy, flies
+    500 feet with the first woman passenger ever carried on an
+    aeroplane--Mrs. Peltier.
+
+    _August 9, 1908_--Wilbur Wright with biplane, at Le Mans, France,
+    makes several short flights to prove the ease of control of his
+    machine.
+
+    _August 8, 1908_--L. F. Ferber with biplane, at Issy, makes first
+    trial flights.
+
+    _September 6, 1908_--Delagrange with biplane, at Issy, flies
+    15.2 miles in 29 minutes and 52 seconds, beating existing French
+    records.
+
+    _September 8, 1908_--Orville Wright with biplane, at Fort Myer,
+    Va., flies 40 miles in 1 hour and 2 minutes, rising to 100 feet.
+
+    _September 9, 10, 11, 1908_--Orville Wright with biplane, at
+    Fort Myer, makes several flights, increasing in duration from 57
+    minutes to 1 hour ten minutes and 24 seconds.
+
+    _September 12, 1908_--Orville Wright with biplane, at Fort Myer,
+    flies 50 miles in 1 hour, 14 minutes and 20 seconds, the longest
+    flight on record.
+
+    _September 12, 1908_--Orville Wright with biplane, at Fort Myer,
+    flies for 9 minutes and 6 seconds with one passenger (Major
+    Squier), making a new record.
+
+    _September 17, 1908_--Orville Wright with biplane, at Fort Myer,
+    flies 3 miles in 4 minutes, with Lieutenant Selfridge. The
+    machine fell: Selfridge was killed and Wright severely injured.
+
+    _September 19, 1908_--L. F. Ferber with biplane, at Issy, flies
+    1,640 feet.
+
+    _September 21, 1908_--Wilbur Wright with biplane, at Auvours,
+    flies 41 miles in 1 hour and 31 minutes.
+
+    _September 25, 1908_--Wilbur Wright with biplane, at Le Mans,
+    France, flies 11 minutes and 35 seconds, with one passenger,
+    making a new record.
+
+    _October 3, 1908_--Wilbur Wright with biplane, at Le Mans,
+    France, flies 55 minutes and 37 seconds, with one passenger,
+    making new record.
+
+    _October 6, 1908_--Wilbur Wright with biplane, at Le Mans, flies
+    1 hour 4 minutes and 26 seconds, with one passenger, breaking all
+    records.
+
+    _October 10, 1908_--Wilbur Wright with biplane, at Auvours,
+    flies 46 miles in 1 hour and 9 minutes, with one passenger (Mr.
+    Painleve). Also carried 35 others on different trips, one at a
+    time.
+
+    _October 21, 1908_--Bleriot with monoplane, at Toury, France,
+    flies 4.25 miles in 6 minutes and 40 seconds.
+
+    _October 30, 1908_--Farman with biplane at Chalons, France, makes
+    a flight across country to Rheims--17 miles in 20 minutes.
+
+    _October 31, 1908_--Farman with biplane, at Chalons, flies 23
+    minutes, reaching a height of 82 feet.
+
+    _October 31, 1908_--Bleriot with monoplane, at Toury, flies 8.7
+    miles to Artenay, in 11 minutes, lands, and returns to Toury.
+
+    _December 18, 1908_--Wilbur Wright with biplane, at Auvours,
+    flies 62 miles in 1 hour and 54 minutes, rising to 360
+    feet--making a world record.
+
+    _December 31, 1908_--Wilbur Wright with biplane, at Le Mans,
+    flies 76.5 miles in 2 hours 18 minutes and 53 seconds, making a
+    new world record, and winning the Michelin prize. The distance
+    traversed (unofficial) is claimed to have been actually over 100
+    miles.
+
+    _January 28, 1909_--Moore-Brabazon with biplane, at Chalons,
+    flies 3.1 miles, in practice with a Voison machine.
+
+    _February 14, 1909_--Legagneux with biplane, at Mourmelon,
+    France, flies 1.2 miles, and in a second flight of 6.2 miles (10
+    kilometres), traces two circles.
+
+    _February 22, 1909_--S. F. Cody with biplane, at Aldershot,
+    England, flies 1,200 feet in a 12-mile wind.
+
+    _February 23, 1909_--J. A. D. McCurdy, with the biplane “Silver
+    Dart,” at Baddeck, Cape Breton, flies 2,640 feet.
+
+    _February 24, 1909_--McCurdy, with the biplane “Silver Dart,” at
+    Baddeck, flies 4.5 miles.
+
+    _February 24, 1909_--Moore-Brabazon, with biplane, at Issy, flies
+    1.2 miles, tracing two circles.
+
+    _February 28, 1909_--Moore-Brabazon made several flights at Issy.
+
+    _March 8, 1909_--McCurdy, with biplane “Silver Dart,” at Baddeck,
+    made five flights, the longest about 8 miles in 11 minutes and 15
+    seconds.
+
+    _March 10, 1909_--Santos-Dumont, with monoplane “Libellule,” at
+    Bagatelle, flies 1,300 feet.
+
+    _March 11, 1909_--W. J. Richardson with a new form of aeroplane,
+    at Dayton, O., flies for 38 minutes, rising to a height of over
+    300 feet.
+
+    _March 11, 1909_--McCurdy with biplane “Silver Dart,” at Baddeck,
+    flies 19 miles in 22 minutes.
+
+    _March 17, 1909_--Count de Lambert (pupil of Wilbur Wright) made
+    his first flight alone in biplane, at Pau, France. He remained in
+    the air 3 minutes.
+
+    _March 18, 1909_--McCurdy, with biplane “Silver Dart,” at
+    Baddeck, flies 16 miles, completing a record of an even 1,000
+    miles in the air within a period of 10 months.
+
+    _March 18, 1909_--F. W. Baldwin with biplane “Silver Dart,” at
+    Baddeck, made a short flight.
+
+    _March 20, 1909_--Wilbur Wright, with biplane, at Pau, succeeds
+    in rising from the ground without the starting device previously
+    used. He makes several flights.
+
+    _March 24, 1909_--Count de Lambert with biplane, at Pau, flies
+    15.6 miles in 27 minutes and 11 seconds.
+
+    _April 10, 1909_--Santos-Dumont with monoplane “Demoiselle,” at
+    St. Cyr, France, flies 1.2 miles.
+
+    _April 13, 1909_--Count de Lambert with biplane, at Pau, flies
+    for 1 minute and 30 seconds, with one passenger (Leon Delagrange).
+
+    _April 16, 1909_--Wilbur Wright with biplane, at Rome, Italy,
+    made many flights, taking up many passengers, one at a time.
+
+    _April 27, 1909_--Legagneux with Voisin biplane, at Vienna, flies
+    2.5 miles in 3 minutes and 26 seconds.
+
+    _April 28, 1909_--Lieutenant Mario Calderara (pupil of Wilbur
+    Wright) with biplane, at Rome, made his first public flight,
+    remaining in the air 10 minutes.
+
+    _April 30, 1909_--Moore-Brabazon with biplane, in England, flies
+    4.5 miles.
+
+    _May 14, 1909_--S. F. Cody, with the army biplane, at Aldershot,
+    flies 1 mile.
+
+    _May 19, 1909_--Hubert Latham, with Antoinette monoplane, at
+    Chalons, flies 1,640 feet.
+
+    _May 20, 1909_--Paul Tissandier (pupil of Wilbur Wright) with
+    biplane at Pau, flies 35.7 miles.
+
+    _May 23, 1909_--Delagrange, with biplane, at Juvissy, flies 3.6
+    miles in 10 minutes and 18 seconds, winning the Lagatineri prize.
+
+    _May 23, 1909_--Henri Rougier, with biplane, at Juvissy, flies
+    18.6 miles (30 kilometres).
+
+    _May 30, 1909_--Bleriot, with monoplane at Issy, flies 8.7 miles.
+
+    _June 5, 1909_--Latham, with monoplane, at Chalons, flies for 1
+    hour 7 minutes and 37 seconds in wind and rain.
+
+    _June 6, 1909_--Latham, with monoplane, at Juvissy, flies 10
+    miles across country.
+
+    _June 12, 1909_--Latham, with monoplane, at Juvissy, flies 30
+    miles in 39 minutes, winning the Goupy prize.
+
+    _June 12, 1909_--Delagrange, with biplane, at Juvissy, makes
+    cross country flight of 3.7 miles.
+
+    _June 12, 1909_--Bleriot, with monoplane, at Juvissy, flies 984
+    feet, with two passengers--Santos-Dumont and Fournier.
+
+    _June 13 1909_--Ferber, with Voisin biplane, at Juvissy, flies
+    3.1 miles in 5 minutes and 30 seconds.
+
+    _June 19, 1909_--Santos-Dumont, with monoplane, at Issy, makes
+    several flights.
+
+    _July 4, 1909_--Roger Sommer with biplane, at Chalons, flies 3.75
+    miles on Farman machine.
+
+    _July 10, 1909_--Louis Paulhan, with biplane, at Douai, France,
+    makes his first flight--1.25 miles.
+
+    _July 13, 1909_--Curtiss, with biplane, at Mineola, L. I., flies
+    1.5 miles in 3 minutes.
+
+    _July 13, 1909_--Bleriot, with monoplane, at Mondesir, makes a
+    flight of 26 miles across country in 44 minutes and 30 seconds.
+
+    _July 15, 1909_--Paulhan with biplane, at Douai, flies for 1
+    minute and 17 seconds, soaring to an altitude of 357 feet.
+
+    _July 17, 1909_--Orville Wright, with biplane, at Fort Myer,
+    flies 16 minutes and 40 seconds, at a speed of 40 miles an hour.
+
+    _July 17, 1909_--Curtiss, with biplane, at Mineola, makes 15
+    miles in 21 minutes, describing circles in both directions, as in
+    the figure 8.
+
+    _July 18, 1909_--Curtiss, with biplane, at Hempstead Plains,
+    L. I., flies 29½ miles in 52 minutes and 30 seconds, a flight
+    exceeded only by the Wrights, in America, and Bleriot, Latham,
+    and Paulhan, in Europe.
+
+    _July 18, 1909_--Farman, with biplane, at Chalons, flies for 1
+    hour and 23 minutes, making his first long flight.
+
+    _July 18, 1909_--Sommer, with biplane, at Chalons, makes his
+    longest flight--1 hour and 40 minutes.
+
+    _July 19, 1909_--Latham, with monoplane, at Calais, France, makes
+    his first attempt to cross the Channel to Dover. He flies 11
+    miles, and then his machine falls into the sea.
+
+    _July 19, 1909_--Paulhan, with biplane, at Douai, makes a
+    cross-country flight of 12.1 miles in 22 minutes and 53 seconds.
+
+    _July 20, 1909_--Orville Wright, with biplane, at Fort Myer,
+    flies 1 hour and 20 minutes.
+
+    _July 21, 1909_--Orville Wright, with biplane, at Fort Myer,
+    flies 1 hour and 29 minutes.
+
+    _July 21, 1909_--E. Lefebvre, with biplane, at La Haye, France,
+    flies 2 miles.
+
+    _July 21, 1909_--S. F. Cody, with biplane, at Aldershot, flies 4
+    miles.
+
+    _July 23, 1909_--Farman, with biplane, at Chalons, makes a
+    cross-country flight to Suippes--40 miles in 1 hour and five
+    minutes.
+
+    _July 23, 1909_--Paulhan, with biplane, at Douai, flies 43.5
+    miles in 1 hour 17 minutes and 19 seconds.
+
+    _July 24, 1909_--Curtiss in biplane, at Hempstead Plains, flies
+    25 miles in 52 minutes and 30 seconds, winning the _Scientific
+    American_ cup the second time.
+
+    _July 25, 1909_--Bleriot, with monoplane, at Calais, flies to
+    Dover, England, across the English Channel--32 miles in 37
+    minutes.
+
+    _July 27, 1909_--Orville Wright, with biplane, at Fort Myer,
+    flies 1 hour and 13 minutes, with one passenger, securing
+    acceptance of Wright machine by U. S. Government on the duration
+    specifications.
+
+    _July 27, 1909_--Latham, with monoplane, at Calais, flies 20
+    miles in a second attempt to cross the English Channel. When near
+    Dover the machine fell.
+
+    _July 27, 1909_--Sommer, with biplane, at Chalons, flies to
+    Vadenay and back--25 miles in 1 hour 23 minutes and 30 seconds.
+
+    _July 30, 1909_--Orville Wright, with biplane, at Fort Myer,
+    established a world record with one passenger in a cross-country
+    flight to Shuter’s Hill and back--about 10 miles in 14 minutes
+    and 40 seconds, a speed of about 42 miles an hour--winning a
+    bonus of $25,000 from the U. S. Government.
+
+    _August 1, 1909_--Sommer, with biplane, at Chalons, flies 1 hour
+    50 minutes and 30 seconds, at an average height of 80 feet, over
+    a distance estimated at 70 miles, surpassing all French records.
+
+    _August 2, 1909_--McCurdy, with a new type of machine, at
+    Petawawa, makes several flights.
+
+    _August 2, 1909_--F. W. Baldwin, with biplane, at Petawawa, makes
+    several short flights.
+
+    _August 2, 1909_--Sommer, with biplane, at Chalons, flies to
+    Suippes--9 miles, at the rate of 45 miles an hour.
+
+    _August 4, 1909_--Sommer, with biplane, at Chalons, in the effort
+    to beat Wilbur Wright’s record, flies for 2 hours 0 minutes and
+    10 seconds (Wright’s record flight was 2 hours 20 minutes and 23
+    seconds, made on December 31, 1908).
+
+    _August 5, 1909_--E. Bunau-Varilla, with Voisin biplane, at
+    Chalons, flies for 15 minutes.
+
+    _August 6, 1909_--Legagneux, with biplane, at Stockholm, flies
+    with one passenger, 3,280 feet.
+
+    _August 6, 1909_--Paulhan, with biplane, at Dunkerque, France,
+    flies for 18 minutes and 20 seconds, reaching an altitude of 200
+    feet.
+
+    _August 7, 1909_--Paulhan, with Voisin biplane, at Dunkerque,
+    flies 23 miles in 33 minutes.
+
+    _August 7, 1909_--Sommer, with Voisin biplane, at Chalons, flies
+    for 2 hours 27 minutes and 15 seconds, making new world record
+    for duration.
+
+    _August 13, 1909_--Charles F. Willard, with biplane, at Hempstead
+    Plains, made the longest cross-country flight on record for
+    America--about 12 miles in 19 minutes and 30 seconds. The
+    breaking of his engine caused him to come down. He landed without
+    mishap.
+
+    _August 22, 1909_--Sommer, with biplane, at Rheims, France, flies
+    1 hour 19 minutes and 30 seconds.
+
+    _August 22, 1909_--Legagneux, with biplane, at Rheims, flies 6.2
+    miles in 9 minutes and 56 seconds, winning third prize for speed
+    over course of 10 kilometres.
+
+    _August 22, 1909_--Tissandier, with biplane, at Rheims, flies
+    18.6 miles in 29 minutes. (He won with this record the third
+    prize for speed over 30 kilometres.)
+
+    _August 22, 1909_--E. Bunau-Varilla, with biplane, at Rheims,
+    flies 6.2 miles in 13 minutes and 30 seconds. (With this
+    record he won the thirteenth prize for speed over course of 10
+    kilometres.)
+
+    _August 23, 1909_--Delagrange, with monoplane, at Rheims, flies
+    6.2 miles in 11 minutes and 4 seconds. (He won the tenth prize
+    for speed over 10 kilometres.)
+
+    _August 23, 1909_--Curtiss, with biplane, at Rheims, flies 6.2
+    miles in 8 minutes and 35 seconds--a speed of 42.3 miles an
+    hour--beating the record for speed over course of 10 kilometres.
+
+    _August 23, 1909_--Paulhan, with biplane, at Rheims, flies 18.6
+    miles in 38 minutes and 12 seconds, reaching an altitude of 295
+    feet.
+
+    _August 23, 1909_--Paulhan, with biplane, at Rheims, flies 34.8
+    miles in an endurance test.
+
+    _August 25, 1909_--Paulhan, with biplane, at Rheims, flies 82
+    miles in 2 hours 43 minutes and 25 seconds. (With this record he
+    won the third prize for duration of flight.)
+
+    _August 25, 1909_--Curtiss, with biplane, at Rheims, flies 6.2
+    miles in 8 minutes and 44 seconds, again reducing the time for 10
+    kilometres.
+
+    _August 25, 1909_--Bleriot, with monoplane, at Rheims, flies 6.2
+    miles in 8 minutes and 4 seconds, making a new record for speed
+    over the course of 10 kilometres.
+
+    _August 26, 1909_--Curtiss, in biplane, at Rheims, flies 19 miles
+    in 29 minutes. (With this record he won the tenth prize for
+    duration of flight.)
+
+    _August 26, 1909_--Count de Lambert, with biplane, at Rheims,
+    flies 72 miles in 1 hour and 52 minutes. (With this record he won
+    the fourth prize for duration of flight.)
+
+    _August 26, 1909_--Latham, with monoplane, at Rheims, flies 96.5
+    miles in 2 hours 17 minutes and 21 seconds. (With this record he
+    won the second prize for duration of flight.)
+
+    _August 27, 1909_--Farman, with biplane, at Rheims, flies 112
+    miles in 3 hours 4 minutes and 57 seconds. (This record won for
+    him the first prize for duration of flight.)
+
+[Illustration: Latham flying in his Antoinette at Rheims. To view this
+properly the picture should be held overhead.]
+
+    _August 27, 1909_--Latham, with monoplane, at Rheims, flies to an
+    altitude of 508 feet. (With this record he won first prize for
+    altitude.)
+
+    _August 27, 1909_--Delagrange, with monoplane, at Rheims, flies
+    31 miles. (With this record he won the eighth prize for duration
+    of flight.)
+
+    _August 27, 1909_--Sommer, with biplane, at Rheims, flies 37
+    miles. He won the seventh prize for distance.
+
+    _August 27, 1909_--Tissandier, with biplane, at Rheims, flies 69
+    miles. (This record won for him the sixth prize for distance.)
+
+    _August 27, 1909_--Lefebvre, with biplane, at Rheims, flies 12.4
+    miles in 20 minutes and 47 seconds, exhibiting great daring and
+    skill. (He was fined for “recklessness.”)
+
+    _August 27, 1909_--Bleriot, with monoplane, at Rheims, flies 25
+    miles in 41 minutes. (This record won for him the ninth prize for
+    distance flown.)
+
+    _August 28, 1909_--Lefebvre, with biplane, at Rheims, makes a
+    spectacular flight for 11 minutes with one passenger.
+
+    _August 28, 1909_--Curtiss, with biplane, at Rheims, flies 12.4
+    miles in 15 minutes and 56 seconds, winning the Gordon Bennett
+    cup.
+
+    _August 28, 1909_--Bleriot, with monoplane, at Rheims, flies 6.2
+    miles in 7 minutes and 48 seconds. (With this record he won the
+    first prize for speed over course of 10 kilometres.)
+
+    _August 29, 1909_--Farman, with biplane, at Rheims, flies 6.2
+    miles with two passengers, in 10 minutes and 30 seconds, winning
+    a prize.
+
+    _August 29. 1909--Curtiss, with biplane, at Rheims, flies 18.6
+    miles in 23 minutes and 30 seconds. (With this record he won the
+    first prize for speed over course of 30 kilometres.)
+
+    _August 29, 1909_--Curtiss, with biplane, at Rheims, flies 6.2
+    miles in 7 minutes and 51 seconds, winning the second prize for
+    speed over course of 10 kilometres.
+
+    _August 29, 1909_--Rougier, with biplane, at Rheims, rises to a
+    height of 180 feet, winning the fourth prize for altitude.
+
+    _August 29, 1909_--E. Bunau-Varilla, with biplane, at Rheims,
+    flies 18.6 miles in 38 minutes and 31 seconds. (With this record
+    he won the eighth prize for speed over course of 30 kilometres.)
+
+    _August 29, 1909_--Orville Wright, with biplane, at Berlin, makes
+    several short flights.
+
+    _August 29, 1909_--S. F. Cody, with biplane, at Aldershot, flies
+    10 miles with one passenger.
+
+    _September 4, 1909_--Orville Wright, with biplane, at Berlin,
+    flies for 55 minutes.
+
+    _September 6, 1909_--Sommer, with biplane, at Nancy, France,
+    flies 25 miles in 35 minutes. He takes up a number of passengers;
+    one at a time.
+
+    _September 7, 1909_--Lefebvre, with biplane, at Juvissy, is
+    killed by the breaking of his machine in the air after he had
+    flown 1,800 feet.
+
+    _September 8, 1909_--Orville Wright, with biplane, at Berlin,
+    flies 17 minutes with one passenger--Captain Hildebrandt.
+
+    _September 8, 1909_--S. F. Cody, with biplane, at Aldershot,
+    flies to Farnborough and back--46 miles in 1 hour and 3 minutes.
+    This is the first recorded cross-country flight in England.
+
+    _September 9, 1909_--Orville Wright, with biplane, at Berlin,
+    flies for 15 minutes with one passenger--Captain Englehardt.
+
+    _September 9, 1909_--Paulhan, with biplane, at Tournai, Belgium,
+    flies 12.4 miles in 17 minutes.
+
+    _September 9, 1909_--Rougier, with biplane, at Brescia, flies 12
+    minutes and 10 seconds, soaring to a height of 328 feet.
+
+    _September 10, 1909_--Sommer, with biplane, at Nancy, flies 18
+    miles, accompanying troops on review.
+
+    _September 11, 1909_--Sommer, with biplane, at Nancy, flies to
+    Lenoncourt--24 miles.
+
+    _September 11, 1909_--Curtiss, with biplane, at Brescia, flies 31
+    miles in 49 minutes and 24 seconds, winning the first prize for
+    speed.
+
+    _September 12, 1909_--Rougier, with biplane, at Brescia, flies 31
+    miles in 1 hour 10 minutes and 18 seconds, soaring to a height of
+    380 feet.
+
+    _September 12, 1909_--Calderara, with biplane, at Brescia, flies
+    6.3 miles with one passenger, winning a prize.
+
+    _September 13, 1909_--Paulhan, with biplane, at Tournai, flies to
+    Taintiguies and back in 1 hour and 35 minutes.
+
+    _September 13, 1909_--Santos-Dumont, with monoplane, at St. Cyr,
+    France, flies 5 miles in 12 minutes, to Buc, to visit Maurice
+    Guffroy, on a bet of $200 that each would be the first to visit
+    the other.
+
+    _September 15, 1909_--Ferber, with biplane, at Boulogne, France,
+    flies to Wimeroux--6 miles in 9 minutes.
+
+    _September 15, 1909_--Calderara, with biplane, at Brescia, flies
+    5.6 miles with one passenger, winning the Oldofredi prize.
+
+    _September 17, 1909_--Orville Wright, with biplane, at Berlin,
+    flies for 54 minutes and 26 seconds, rising to an altitude of
+    765 feet (estimated). He afterward flew for 47 minutes and 5
+    seconds with Captain Englehardt.
+
+    _September 17, 1909_--Santos-Dumont, with monoplane, at St. Cyr,
+    flies 10 miles in 16 minutes across country.
+
+    _September 17, 1909_--Paulhan, with biplane, at Ostend, Belgium,
+    flies 1.24 miles in 3 minutes and 16 seconds, along the water
+    front and out over the sea.
+
+    _September 18, 1909_--Orville Wright, with biplane, at Berlin,
+    establishes a world record by flying for 1 hour 35 minutes and 47
+    seconds, with one passenger--Captain Englehardt.
+
+    _September 18, 1909_--Paulhan, with biplane, at Ostend, flies for
+    1 hour over sea front, circling over the water; winning a prize
+    of $5,000.
+
+    _September 20, 1909_--Rougier, with biplane, at Brescia, broke
+    the record for high flying by reaching an altitude of 645 feet
+    (official measurement).
+
+    _September 20, 1909_--Calderara, with biplane, at Brescia, flies
+    31 miles in 50 minutes and 51 seconds, winning the second prize
+    for speed.
+
+    _September 22, 1909_--Captain Ferber, with a biplane, at
+    Boulogne, flies 1 mile, when, his engine breaking in the air, his
+    machine falls and he is killed.
+
+    _September 25, 1909_--Wilbur Wright, with biplane, at New York,
+    flies from Governor’s Island around the Statue of Liberty.
+
+    _September 27, 1909_--Latham, in monoplane, at Berlin, flies 6.5
+    miles across country in 13 minutes.
+
+    _September 28, 1909_--Rougier, with biplane, at Berlin, flies 31
+    miles in 54 minutes, soaring to an altitude of 518 feet.
+
+    _September 29, 1909_--Latham in monoplane, at Berlin, flies 42
+    miles in 1 hour and 10 minutes, winning the second prize for
+    distance.
+
+    _September 29, 1909_--Rougier, with biplane, at Berlin, flies 48
+    miles in 1 hour and 35 minutes.
+
+    _September 29, 1909_--Curtiss, with biplane, at New York, makes
+    flights about the harbor from Governor’s Island.
+
+    _September 30, 1909_--Orville Wright, with biplane, at Berlin,
+    soars to a height of 902 feet, making a world record for altitude.
+
+    _September 30, 1909_--Latham, with monoplane, at Berlin, flies 51
+    miles in 1 hour and 23 minutes.
+
+    _October 1, 1909_--Rougier, with biplane, at Berlin, flies 80
+    miles in 2 hours and 38 minutes, winning the first prize for
+    distance and speed.
+
+    _October 2, 1909_--Orville Wright, with biplane, at Berlin, makes
+    a flight of 10 minutes’ duration with the Crown Prince of Germany.
+
+    _October 3, 1909_--Farman, with biplane, at Berlin, flies 62
+    miles in 1 hour and 40 minutes, winning the third prize for
+    distance and speed.
+
+    _October 4, 1909_--Orville Wright, with biplane, at Berlin,
+    soared to an altitude of 1,600 feet, making a world record.
+
+    _October 4, 1909_--Wilbur Wright, with biplane, at New York,
+    flies from Governor’s Island to Grant’s Tomb and back--21 miles
+    in 33 minutes and 33 seconds.
+
+    _October 10, 1909_--Curtiss, with biplane, at St. Louis, Mo.,
+    makes several flights at the Centennial celebration.
+
+    _October 10, 1909_--Paulhan, with biplane, at Pt. Aviation, flies
+    21.5 miles in 21 minutes and 48 seconds.
+
+    _October 12, 1909_--Paulhan, with biplane, at Pt. Aviation, flies
+    3.6 miles in 6 minutes and 11 seconds, winning the prize for
+    slowest flight.
+
+    _October 16, 1909_--Curtiss, with biplane, at Chicago, makes
+    exhibition flights at 45 miles per hour.
+
+    _October 16, 1909_--Sommer, with biplane, at Doncaster, England,
+    flies 9.7 miles in 21 minutes and 45 seconds, making the record
+    for Great Britain.
+
+    _October 16, 1909_--Delagrange, with monoplane, at Doncaster,
+    flies 5.75 miles in 11 minutes and 25 seconds.
+
+    _October 16, 1909_--Cody, with biplane, at Doncaster, flies 3,000
+    feet, when his machine is wrecked, and he is injured.
+
+    _October 18, 1909_--Paulhan, with biplane, at Blackpool, England,
+    flies 14 miles in 25 minutes and 53 seconds.
+
+    _October 18, 1909_--Rougier, with biplane, at Blackpool, flies
+    17.7 miles in 24 minutes and 43 seconds, winning the second prize.
+
+    _October 18, 1909_--Farman, with biplane, at Blackpool, flies 14
+    miles in 23 minutes.
+
+    _October 18, 1909_--Le Blon, with monoplane, at Doncaster, flies
+    22 miles in 30 minutes, in a rainstorm, winning the Bradford cup.
+
+    _October 18, 1909_--Count de Lambert, with biplane, at Juvissy,
+    flies 31 miles to the Eiffel Tower in Paris, and back, in 49
+    minutes and 39 seconds.
+
+    _October 19, 1909_--Le Blon, with monoplane, at Doncaster, flies
+    15 miles in a gale.
+
+    _October 19, 1909_--Paulhan, with biplane, at Blackpool, flies
+    15.7 miles in 32 minutes and 18 seconds, winning the third prize.
+
+    _October 20, 1909_--Farman, with biplane, at Blackpool, flies 47
+    miles in 1 hour, 32 minutes, and 16 seconds, winning the first
+    prize--$10,000.
+
+    _October 20, 1909_--Le Blon, with monoplane, at Doncaster, makes
+    a spectacular flight in a fierce gale.
+
+    _October 21, 1909_--Count de Lambert, with biplane, at Pt.
+    Aviation, flies 1.25 miles in 1 minute and 57 seconds, winning
+    prize of $3,000 for speed.
+
+    _October 22, 1909_--Latham, with monoplane, at Blackpool, flies
+    in a squally gale blowing from 30 to 50 miles an hour. When
+    headed into the wind the machine moved backward in relation to
+    points on the ground. Going before the wind, it passed points on
+    the ground at a speed of nearly 100 miles an hour. This flight,
+    twice around the course, is the most difficult feat accomplished
+    by any aviator up to this date.
+
+    _October 26, 1909_--Sommer, with biplane, at Doncaster, flies
+    29.7 miles in 44 minutes and 53 seconds, winning the Whitworth
+    cup.
+
+    _October 26, 1909_--Delagrange, with monoplane, at Doncaster,
+    flies 6 miles in 7 minutes and 36 seconds--a speed of over 50
+    miles an hour.
+
+    _October 30, 1909_--Moore-Brabazon, with biplane, at Shell Beach,
+    England, wins a prize of $5,000 for flight with a British machine.
+
+    _November 3, 1909_--Farman, with biplane, at Mourmelon, France,
+    flies 144 miles in 4 hours 6 minutes and 25 seconds, far
+    surpassing his previous best record of 112 miles in 3 hours 4
+    minutes and 57 seconds, made at Rheims, and winning the Michelin
+    cup for duration and distance.
+
+    _November 19, 1909_--Paulhan, with biplane, at Mourmelon, broke
+    the record for height by ascending to 1,170 feet, in a wind
+    blowing from 20 to 25 miles an hour.
+
+    _November 19, 1909_--Latham, with Antoinette monoplane, surpassed
+    Paulhan’s record by rising to an altitude of 1,333 feet.
+
+    _November 20, 1909_--Paulhan, with biplane, at Mourmelon, flies
+    to Chalons and back--37 miles in 55 minutes.
+
+    _December 1, 1909_--Latham, with monoplane, at Mourmelon, soars
+    to 1,500 feet in a 40-mile gale.
+
+    _December 30, 1909_--Delagrange, with monoplane, at Juvissy,
+    flies 124 miles in 2 hours and 32 minutes--an average speed of
+    48.9 miles per hour, surpassing all previous records.
+
+    _December 31, 1909_--Farman at Chartres, France, flies to
+    Orleans--42 miles in 50 minutes.
+
+    _December 31, 1909_--Maurice Farman, at Mourmelon, defending his
+    brother Henry’s record against competing aviators, flies 100
+    miles in 2 hours and 45 minutes, without a fault. The Michelin
+    cup remains in his brother’s possession.
+
+    _January 7, 1910_--Latham, with Antoinette monoplane, at Chalons,
+    rises to height of 3,281 feet (world’s record).
+
+    _January 10, 1910_--Opening of aviation meet at Los Angeles, Cal.
+
+    _January 12, 1910_--Paulhan, Farman biplane, at Los Angeles,
+    rises to height of 4,146 feet. (World’s record.)
+
+    _January 17, 1910_--Paulhan, Farman biplane, at Los Angeles,
+    flies 75 miles in 1 hour 58 minutes and 27⅖ seconds.
+
+    _February 7, 1910_--First flight in South America. Bregi, Voisin
+    biplane, makes two flights near Buenos Aires.
+
+    _February 7, 1910_--Duray, with Farman biplane, at Heliopolis,
+    Egypt, flies 5 kilometres in 4 minutes and 12⅘ seconds. (World’s
+    record.)
+
+    _April 8, 1910_--D. Kinet, with Farman biplane, at Mourmelon,
+    flies for 2 hours 19 minutes and 4⅖ seconds with passenger,
+    covering 102 miles. (World’s record for passenger flight.)
+
+    _April 11, 1910_--E. Jeannin, with Farman biplane, flies 2 hours
+    1 minute and 55 seconds, at Johannisthal. (German record.)
+
+    _April 15, 1910_--Opening of Nice meeting.
+
+    _April 17, 1910_--Paulhan, with Farman biplane, flies from
+    Chevilly to Arcis-sur-Aube, 118 miles. (Record cross-country
+    flight.)
+
+    _April 23, 1910_--Grahame-White, with Farman biplane, flies from
+    Park Royal, London, to Rugby (83 miles) in 2 hours and 1 minute.
+    Starting again in 55 minutes, flies to Whittington in 1 hour and
+    5 minutes.
+
+    _April 27, 1910_--Paulhan, with Farman biplane, starts from
+    Hendon, London, at 5.31 P. M., flies within 5 mile circle
+    and continues to Lichfield, arriving 8.10 P. M. (117 miles).
+    Grahame-White starts from Wormwood Scrubs, London, at 6.29 P.
+    M., flies to Roade, arriving 7.55 P. M. (60 miles).
+
+    _April 28, 1910_--Paulhan flies from Lichfield to within 5 miles
+    of Manchester, winning the £10,000 _Daily Mail_ prize.
+
+    _April 30, 1910_--Opening of meeting at Tours, France.
+
+    _May 1, 1910_--Opening of flying-week at Barcelona.
+
+    _May 3, 1910_--Wiencziers, with Antoinette monoplane, twice
+    circles the Strassburg cathedral.
+
+    _May 6, 1910_--Olieslagers, with Bleriot monoplane, makes flight
+    of 18 minutes and 20 seconds above the sea at Barcelona, and over
+    the fortress of Monjuich.
+
+    _May 13, 1910_--Engelhardt, with Wright biplane, at Berlin, flies
+    2 hours 21 minutes and 45 seconds. (German record.)
+
+    _May 15, 1910_--Kinet, with Farman biplane, flies 2 hours and 51
+    minutes with a passenger at Mourmelon, making the world’s record
+    for passenger flight.
+
+    _May 15, 1910_--Olieslagers, with Bleriot monoplane, flies 15
+    miles over the sea at Genoa.
+
+    _May 21, 1910_--M. de Lesseps, with Bleriot monoplane, flies
+    from Calais to Dover in 37 minutes, winning £500 prize offered by
+    M. M. Ruinart.
+
+    _May 28, 1910_--G. Curtiss, with Curtiss biplane, starts from
+    Albany at 7.03 A. M., flies to Poughkeepsie in 1 hour and 21
+    minutes (70 miles). Leaves Poughkeepsie at 9.24 A. M., flies to
+    Spuyten Duyvil in 1 hour and 11 minutes (67 miles). Rises again
+    at 11.45, flies over New York, landing on Governor’s Island at
+    12.03 P. M. Wins prize of $10,000 given by the New York _World_.
+
+    _June 2, 1910_--Rolls, with Short-Wright biplane, leaves Dover
+    at 6.30 P. M., crosses Channel to French coast near Calais (7.15
+    P. M.), without landing re-crosses Channel to Dover, flies over
+    harbor, circles Dover Castle, and lands at 8.10 P. M. Wins second
+    Ruinart prize of £80.
+
+    _June 14, 1910_--Brookins, with Wright biplane, at Indianapolis,
+    reaches height of 4,380 feet. (World’s record.)
+
+    _June 25, 1910_--In Italian Parliament 25 million lire (about
+    $5,000,000) voted for aviation in the extraordinary estimates of
+    the Ministry of War.
+
+    _June 26, 1910_--Dickson, with Farman biplane, at Rouen, wins
+    total distance prize of £2,000 and the £400 for longest unbroken
+    flight. Distance flown, 466 miles.
+
+    _June 27, 1910_--M. de Lesseps, with Bleriot monoplane, flies
+    over Montreal for 49 minutes, covering about 30 miles at height
+    generally of 2,000 feet.
+
+    _July 6, 1910_--First German military aeroplane makes maiden
+    cross-country flight over Doeberitz.
+
+    _July 26, 1910_--M. de Lesseps, with Bleriot monoplane, starting
+    from Ile de Gros Bois in the St. Lawrence, makes trip of 40 miles
+    in 37 minutes.
+
+    _August 1, 1910_--Henry Farman takes up three passengers at
+    Mourmelon for 1 hour and 4 minutes.
+
+    _August 5, 1910_--Chavez, with Bleriot monoplane, attains height
+    of 5,750 feet. World’s record.
+
+    _August 7, 1910_--Lieutenants Cammerman and Villerme fly together
+    from Mourmelon to Nancy, 125 miles in 2½ hours, with a Farman
+    biplane.
+
+    _August 11, 1910_--Drexel, with Bleriot monoplane, at Lanark,
+    beats the world’s record for height, rising 6,600 feet.
+
+    _August 27, 1910_--First wireless telegram from a flying
+    aeroplane, sent by McCurdy from a Curtiss machine in the air,
+    at Atlantic City, N. J. The sending key was attached to the
+    steering wheel.
+
+    _August 28, 1910_--Dufaux, with biplane constructed by himself,
+    flies over Lake Geneva, wins prize of £200 offered by Swiss Aero
+    Club.
+
+    _August 29, 1910_--Breguet, with Breguet monoplane, makes a
+    flight at Lille, France, carrying five passengers, establishing
+    world’s record for passenger flight.
+
+    _August 29, 1910_--Morane, with Bleriot monoplane, at Havre,
+    beats world’s altitude record, reaches height of 7,166 feet.
+
+    _September 2, 1910_--Mlle. Hélène Dutrieux flies with a passenger
+    from Ostend to Bruges, Belgium, and back to Ostend. At Bruges she
+    circled around the famous belfry at a height of 1,300 feet, the
+    chimes pealing in honor of the feat--the most wonderful flight so
+    far accomplished by a woman.
+
+    _September 3, 1910_--M. Bielovucci lands at Bordeaux, France,
+    having made the trip from Paris, 366 miles, inside of 48 hours.
+    The actual time in the air was 7 hours 6 minutes. Strong head
+    winds blew him backward, forcing a landing three times on the
+    way. This is the fourth longest cross-country flight on record,
+    and makes the world’s record for sustained speed over a long
+    distance.
+
+[Illustration: Mlle. Hélène Dutrieux.]
+
+    _September 4, 1910_--Morane, at Havre, rises to height of 8,469
+    feet.
+
+    _September 7, 1910_--Weyman, with Farman biplane, flies from Buc
+    in attempt to reach the top of the Puy-de-Dôme, lands at Volvic,
+    5 miles from his destination. Establishes world’s record for
+    flight with passenger, having covered 139 miles without landing.
+
+    _September 28, 1910_--Chavez crosses the Alps on a Bleriot
+    monoplane from Brigue, in Switzerland, to Domodossola, in Italy,
+    flying over the Simplon Pass.
+
+    _October 1, 1910_--Henri Wynmalen, of Holland, with a biplane at
+    Mourmelon, France, rises to a height of 9,121 feet, making a new
+    world’s record for altitude.
+
+    _October 4, 1910_--Maurice Tabuteau recrossed the Pyrenees, in
+    his return trip from San Sebastian to Biarritz, without accident
+    or marked incident.
+
+    _October 5, 1910_--Leon Morane, the winner of nearly all the
+    contests in the English meets for 1910, fell with his monoplane
+    at Boissy St. Leger, during a contest for the Michelin cup, and
+    was seriously injured.
+
+    _October 8, 1910_--Archibald Hoxsey, with a biplane, makes the
+    longest continuous aeroplane flight recorded in America, between
+    Springfield, Ill., and St. Louis, Mo.--104 miles.
+
+    _October 12, 1910_--Alfred Leblanc, with monoplane, at St. Louis,
+    flies 13 miles in 10 minutes, a speed of 78 miles per hour.
+    It was not officially recorded, as a part of the distance was
+    outside of the prescribed course.
+
+    _October 14, 1910_--Grahame-White flies from the Bennings
+    Race Track 6 miles across the Potomac River to the Capitol at
+    Washington, circles the dome, and then circles the Washington
+    Monument, and finally alights with precision in Executive Street,
+    between the Executive Offices and the building of the State,
+    Army, and Navy Departments. After a brief call, he rose from the
+    narrow street--but 20 feet wider than his biplane--and returned
+    to the race track without untoward incident.
+
+    _October 16, 1910_--Wynmalen flies from Paris to Brussels, and
+    returns, with one passenger, within the elapsed time of 27 hours
+    50 minutes, winning two prizes amounting to $35,000. The distance
+    is 350 miles, and the actual time in the air was 15 hours 38
+    minutes.
+
+    _October 25, 1910_--J. Armstrong Drexel, with monoplane, at
+    Belmont Park, L. I., rises to height of 7,105 feet, breaking
+    previous records, and surpassing his own record of 6,600 feet,
+    made at Lanark, Scotland.
+
+    _October 26, 1910_--Ralph Johnstone, in biplane, at Belmont
+    Park, rises to the height of 7,313 feet, through sleet and snow,
+    breaking the new American record made by Drexel the day before.
+
+    _October 27, 1910_--Johnstone, with biplane, at Belmont Park,
+    rises to height of 8,471 feet, surpassing his own record of the
+    day before and establishing a new American record. The feat was
+    performed in a gale blowing nearly 60 miles per hour, and the
+    aviator was carried 55 miles away from his starting point before
+    he landed.
+
+    _October 28, 1910_--Tabuteau, with biplane, at Etampes, France,
+    makes a new world’s endurance record of 6 hours’ continuous
+    flight, covering a distance of 289 miles.
+
+    _October 29, 1910_--Grahame-White, with monoplane, at Belmont
+    Park, wins the International speed race over the distance of 62.1
+    miles, in 1 hour 1 minute 4⅗ seconds.
+
+    _October 29, 1910_--Leblanc, with monoplane, at Belmont Park,
+    makes a new world’s record for speed, reaching 70 miles per hour
+    during the International speed race. Through a lack of fuel he
+    lost the race to Grahame-White, after covering 59 miles in 52
+    minutes.
+
+    _October 30, 1910_--John B. Moisant, with monoplane, wins the
+    race from Belmont Park around the Statue of Liberty in New York
+    harbor, and the prize of $10,000. The distance is about 34 miles,
+    and Moisant covered it in 34 minutes 39 seconds.
+
+    _October 30, 1910_--James Radley, with monoplane, at Belmont
+    Park, wins the cross-country flight of 20 miles in 20 minutes 5
+    seconds.
+
+    _October 31, 1910_--Johnstone, with biplane, at Belmont Park,
+    rises to a height of 9,714 feet, breaking the previous world’s
+    record, made by Wynmalen on October 1.
+
+    _October 31, 1910_--Drexel, with monoplane, racing for altitude
+    with Johnstone, reaches a height of 8,370 feet.
+
+    _October 31, 1910_--Moisant, with monoplane, at Belmont Park,
+    wins the two-hour distance race with a record of 84 miles. His
+    next nearest competitor covered but 57 miles.
+
+    _November 14, 1910_--Eugene Ely, with biplane, flew from a
+    staging on the deck of the U. S. Cruiser _Birmingham_ 8 miles
+    to the shore near the mouth of Chesapeake Bay. The flight was
+    intended to end at the Norfolk Navy Yard, but an accident to the
+    propeller at starting forced Ely to make directly for the shore.
+
+    _November 17, 1910_--Ralph Johnstone, holder of the world’s
+    altitude record of 9,714 feet, was killed at Denver, Col., by a
+    fall with his biplane.
+
+    _November 23, 1910_--Drexel, at Philadelphia, reaches an altitude
+    of 9,970 feet, passing all other altitude records. Coming down he
+    made a straight glide of seven miles.
+
+    _December 2, 1910_--Charles K. Hamilton, at Memphis, Tenn., flies
+    4 miles in 3 minutes 1 second, a speed of 79.2 miles per hour.
+    This is a new world’s record.
+
+
+
+
+Chapter XX.
+
+EXPLANATION OF AERONAUTICAL TERMS.
+
+
+Every development in human progress is marked by a concurrent
+development in language. To express the new ideas, new words appear, or
+new meanings are given to words already in use.
+
+As yet, the vocabulary of aeronautics is in the same constructive and
+incomplete state as is the science to which it attempts to give voice,
+and the utmost that can be done at this time is to record such words
+and special meanings as are in use in the immediate present.
+
+
+A
+
+    _Adjusting Plane_--A small plane, or surface, at the outer end of
+    a wing, by which the lateral (from side to side) balance of an
+    aeroplane is adjusted. It is not connected with the controlling
+    mechanism, as are the ailerons--nor with any automatic device.
+
+    _Aerodrome_--A term used by Professor Langley as a better
+    name for the aeroplane; but latterly it has been applied to
+    the buildings in which airships are housed, and also in a few
+    instances, as a name for the course laid out for aeronautical
+    contests.
+
+    _Aerofoil_--Another name for the aeroplane, suggested as more
+    accurate, considering that the surfaces are not true planes.
+
+    _Aeronef_--Another name for an aeroplane.
+
+    _Aeroplane_--The type of flying machine which is supported
+    in the air by a spread of surfaces or planes, formerly flat,
+    and therefore truly “plane,” but of late more or less curved.
+    Even though not absolutely accurate, this term has resisted
+    displacement by any other.
+
+    _Aerostat_--A free balloon afloat in the air.
+
+    _Aeronate_--A captive balloon.
+
+    _Aileron_--A small movable plane at the wing-tips, or hinged
+    between the main planes, usually at their outer ends, operated by
+    the aviator to restore the lateral balance of the machine when
+    disturbed.
+
+    _Air-speed_--The speed of aircraft as related to the air in which
+    they are moving; as distinguished from land-speed (which see).
+
+    _Alighting Gear_--Devices on the under side of the aeroplane to
+    take up the jar of landing after flight, and at the same time to
+    check the forward motion at that moment.
+
+    _Angle of Entry_--The angle made by the tangent to the curve of
+    the aeroplane surface at its forward edge, with the direction, or
+    line, of travel.
+
+    _Angle of Incidence_--The angle made by the chord of the arc of a
+    curved “plane,” or by the line of a flat plane, with the line of
+    travel.
+
+[Illustration]
+
+    _Angle of Trail_--The angle made by the tangent to the rear edge
+    of a curved plane with the line of travel.
+
+    _Apteroid_--A form resembling the “short and broad” type of the
+    wings of certain birds--as distinguished from the pterygoid
+    (which see).
+
+    _Arc_--Any part of a circle, or other curved line.
+
+    _Arch_--The curve formed by bending the wings downward at the
+    tips, leaving them higher at the centre of the machine.
+
+    _Aspect_--The view of the top of an aeroplane as it appears when
+    looked down upon from above.
+
+    _Aspiration_--The (hitherto) unexplained tendency of a curved
+    surface--convex side upward--to rise and advance when a stream of
+    air blows against its forward edge and across the top.
+
+    _Attitude_--The position of a plane as related to the line of its
+    travel; usually expressed by the angle of incidence.
+
+    _Automatic Stability_--That stability which is preserved by
+    self-acting, or self-adjusting, devices which are not under the
+    control of the operator, nor a fixed part of the machine, as are
+    the adjusting planes.
+
+    _Aviation_--Flying by means of power-propelled machines which are
+    not buoyed up in the air, as with gas bags.
+
+    _Aviator_--The operator, driver, or pilot of an aeroplane.
+
+
+B
+
+    _Balance_--Equilibrium maintained by the controlling mechanism,
+    or by the automatic action of balancing-surfaces--as
+    distinguished from the equilibrium preserved by stabilizing
+    surfaces.
+
+    _Balancing Plane_--The surface which is employed either
+    intentionally, or automatically, to restore a disturbed balance.
+
+    _Biplane_--The type of aeroplane which has two main supporting
+    surfaces or planes, placed one above the other.
+
+    _Body_--The central structure of an aeroplane, containing the
+    machinery and the passenger space--as distinguished from the
+    wings, or planes, and the tail.
+
+    _Brace_--A construction member of the framing of aircraft
+    which resists a compression strain in a diagonal direction--as
+    distinguished from a “stay,” or “diagonal,” which supports a
+    pulling strain; also from a strut which supports a compression
+    strain in a vertical direction.
+
+
+C
+
+    _Camber_--The distance from the chord of the curve of a surface
+    to the highest point of that curve, measured at right angles to
+    the chord.
+
+    _Caster_, or _Castor_, _Wheel_--A wheel mounted on an upright
+    pivoted shaft placed forward of its axle, so that it swivels
+    automatically to assume the line of travel of an aeroplane when
+    landing: used in the alighting gear. To be distinguished from a
+    fixed wheel, which does not swivel.
+
+    _Cell_--A structure with enclosing sides--similar to a box
+    without top or bottom stood upon one side. The vertical walls
+    of the cell give lateral stability, and its horizontal walls
+    fore-and-aft stability.
+
+[Illustration: The first Santos-Dumont biplane, constructed of cells.]
+
+    _Centre of Gravity_--That point of a body where its weight
+    centres. If this point is supported, the body rests in exact
+    balance.
+
+    _Centre of Lift_--The one point at which the lifting forces of
+    the flying planes might be concentrated, and produce the same
+    effect.
+
+    _Centre of Resistance_--The one point at which the forces
+    opposing the flight of an air-craft might be concentrated, and
+    produce the same result.
+
+    _Centre of Thrust_--The one point at which the forces generated
+    by the revolving propellers might be concentrated, and produce
+    the same effect.
+
+    _Chassis_--The under-structure or “running-gear” of an aeroplane.
+
+    _Chord_--The straight line between the two ends of an arc of a
+    circle or other curved line.
+
+    _Compound Control_--A mechanical system by which several distinct
+    controls are operated through different manipulations of the same
+    lever or steering-wheel.
+
+    _Compression Side_--That side of a plane or propeller blade
+    against which the air is compressed--the under surface of a
+    flying plane, and the rear surface of a revolving propeller.
+
+    _Curtain_--The vertical surface of a cell--the wall which stands
+    upright.
+
+
+D
+
+    _Deck_--A main aeroplane surface. The term is used generally in
+    describing biplanes; as the upper deck, and the lower deck; or
+    with aeroplanes of many decks.
+
+    _Demountable_--A type of construction which permits a machine to
+    be easily taken apart for transportation.
+
+    _Derrick_--A tower-shaped structure in which a weight is raised
+    and allowed to fall to give starting impetus to an aeroplane.
+
+    _Dihedral_--That form of construction in which the wings of an
+    aeroplane start with an upward incline at their junction with the
+    body of the machine, instead of stretching out on a level.
+
+    _Dirigible_--The condition of being directable, or steerable:
+    applied generally to the balloons fitted with propelling power,
+    or airships.
+
+    _Double Rudder_--A rudder composed of two intersecting planes,
+    one vertical and the other horizontal, thus enabling the operator
+    to steer in any direction with the one rudder.
+
+[Illustration]
+
+    _Double-Surfaced_--Planes which are covered with fabric on both
+    their upper and lower surfaces, thus completely inclosing their
+    frames.
+
+    _Down-Wind_--Along with the wind; in the direction in which the
+    wind is blowing.
+
+    _Drift_--The recoil of an aeroplane surface forced through the
+    air: also the tendency to float in the same direction as the wind.
+
+
+E
+
+    _Elevator_--A shorter name for the elevating planes or elevating
+    rudder, used for directing the aeroplane upward or downward.
+
+    _Ellipse_--An oval figure outlined by cutting a cone through from
+    side to side on a plane not parallel to its base. Some inventors
+    use the curves of the ellipse in forming the wings of aeroplanes.
+    See Hyperbola and Parabola.
+
+    _Entry_--The penetration of the air by the forward edge of
+    aircraft surfaces. See Angle of Entry.
+
+    _Equivalent Head Area_--Such an area of flat surface as will
+    encounter head resistance equal to the total of that of the
+    construction members of the framework--struts, braces, spars,
+    diagonals, etc., of the aerial craft.
+
+
+F
+
+    _Feathering_--A form of construction in which mounting on hinges,
+    or pivots, permits the surfaces to engage the air flatwise in one
+    direction and to pass edgewise through it in other directions.
+
+    _Fin_--A fixed vertical stabilizing surface, similar in form to
+    the fin on the back of a fish.
+
+    _Fish Section_--A term applied to the lengthwise section of
+    an aircraft when the outline resembles the general shape of a
+    fish--blunted in front and tapering toward the rear. This form is
+    believed to encounter less resistance than any other, in passing
+    through the air.
+
+    _Fixed Wheel_--A wheel in a fixed mounting, so that it does not
+    swivel as does a caster wheel.
+
+    _Flapping Flight_--Flight by the up-and-down beating of wings,
+    similar to the common flight of pigeons.
+
+    _Flexible Propeller_--A propeller in which the blades are frames
+    covered more or less loosely with a fabric which is in a measure
+    free to adjust its form to the compression of the air behind it
+    as it revolves.
+
+    _Flying Angle_--The angle of incidence of the main surface of an
+    aeroplane when in flight. See Ground Angle.
+
+    _Footpound_--The amount of force required to raise one pound to
+    a height of one foot.
+
+    _Fore-and-aft_--From front to rear: lengthwise: longitudinal.
+
+    _Fuselage_--The framework of the body of an aeroplane.
+
+
+G
+
+    _Glider_--A structure similar to an aeroplane, but without motive
+    power.
+
+    _Gliding_--Flying down a slope of air with a glider, or with an
+    aeroplane in which the propelling power is cut off.
+
+    _Gliding Angle_--The flattest angle at which a given machine will
+    make a perfect glide. This angle differs with different machines.
+    The flatter the gliding angle the safer the machine.
+
+    _Ground Angle_--The angle of incidence of an aeroplane surface
+    when the machine is standing on the ground.
+
+    _Guy_--A wire attached to a more or less distant part of the
+    structure of any aircraft to prevent spreading. Also used to
+    denote controlling wires which transmit the movements of the
+    levers.
+
+    _Gyroscopic Action_--The resistance which a rotating wheel, or
+    wheel-like construction, exhibits when a disturbing force tends
+    to change its plane of rotation.
+
+
+H
+
+    _Hangar_--A structure for the housing of aeroplanes.
+
+    _Head Resistance_--The resistance encountered by a surface moving
+    through the air.
+
+    _Heavier-than-air_--A term applied to flying machines whose
+    weight is not counterbalanced or buoyed up by the lifting power
+    of some gas lighter than air; and which weigh more than the
+    volume of air displaced.
+
+    _Helicopater_--A type of flying machine in which propellers
+    revolving horizontally lift and sustain its weight in the air.
+
+    _Horizontal Rudder_--The rudder surface which is used to steer an
+    aircraft upward or downward: so-called because it lies normally
+    in a position parallel to the horizon; that is, level.
+
+    _Horse-power_--An amount of work equivalent to the lifting of
+    33,000 footpounds in one minute. See Footpound.
+
+    _Hyperbola_--The outline formed by the cutting of a cone by a
+    plane passing one side of its axis at such an angle that it would
+    also intersect another cone placed apex to apex on the same axis.
+
+
+K
+
+    _Keel_--A framework extending lengthwise under an aircraft to
+    stiffen the construction: usually employed on airships with
+    elongated gas-bags.
+
+
+L
+
+    _Lateral_--From side to side; that is, crossing the length
+    fore-and-aft, and generally at right angles to it.
+
+    _Land-speed_--The speed of aircraft as related to objects on the
+    ground. See Air-speed.
+
+    _Landing Area_--A piece of land specially prepared for the
+    alighting of aeroplanes without risk of injury.
+
+    _Leeway_--Movement of a machine aside from the intended course,
+    due to the lateral drift of the whole body of air; measured
+    usually at right angles to the course.
+
+    _Lift_--The raising, or sustaining effect of an aeroplane
+    surface. It is expressed in the weight thus overcome.
+
+    _Lighter-than-air_--A term used to designate aircraft which,
+    owing to the buoyancy of the gas attached, weigh less than the
+    volume of air which they displace.
+
+    _Longitudinal_--In a lengthwise, or fore-and-aft direction.
+
+
+M
+
+    _Main Plane_--The principal supporting surface of an aeroplane.
+    In the biplane, or the multiplane type, it denotes the lowest
+    surface, unless some other is decidedly larger.
+
+    _Main Landing Wheels_--Those wheels on the alighting gear which
+    take the shock in landing.
+
+    _Mast_--A vertical post or strut giving angular altitude to
+    guys or long stays. Also used (erroneously) to designate a spar
+    reaching out laterally or longitudinally in a horizontal position.
+
+    _Monoplane_--An aeroplane with one main supporting surface. A
+    Double Monoplane has two of such surfaces set one behind the
+    other (tandem) but on the same level.
+
+    _Multiplane_--An aeroplane having several main planes, at least
+    more than three (for which there is the special name of triplane).
+
+
+N
+
+    _Nacelle_--The framework, or body, of a dirigible balloon or
+    airship.
+
+    _Negative Angle of Incidence_--An angle of incidence below the
+    line of travel, and therefore expressed with a minus sign.
+    Surfaces bent to certain curves fly successfully at negative
+    angles of incidence, and exhibit a comparatively large lift.
+
+
+O
+
+    _Ornithopter_--A type of flying machine with wing surfaces which
+    are designed to raise and sustain the machine in the air by
+    flapping.
+
+
+P
+
+    _Panel_--Another name for Curtain--which see.
+
+    _Parabola_--The form outlined when a cone is cut by a plane
+    parallel to a line drawn on its surface from its apex to its
+    base. Declared to be the correct scientific curve for aeroplane
+    surfaces, but not so proven, as yet.
+
+    _Pilot_--A term widely used for an operator, or driver, of any
+    form of aircraft.
+
+    _Pitch_--The distance which a propeller would progress during one
+    revolution, if free to move in a medium which permitted no slip
+    (which see); just as the thread of a bolt travels in the groove
+    of its nut.
+
+    _Plane_--Speaking with exactness, a flat spread of surface; but
+    in aeronautics it includes also the curved sustaining surfaces of
+    aeroplanes.
+
+    _Polyplane_--Another term for Multiplane.
+
+    _Port_--The left-hand side of an aircraft, as one faces forward.
+    See Starboard.
+
+    _Projected Area_--The total area of an irregular structure as
+    projected upon a flat surface; like the total area of the shadow
+    of an object cast by the sun upon a plane fixed at right angles
+    to its rays.
+
+    _Propeller Reaction_--A force produced by a single revolving
+    propeller, which tends to revolve the machine which it is
+    driving, in the contrary direction. This is neutralized in
+    various ways in the machines driven by single propellers. Where
+    two propellers are used it is escaped by arranging them to move
+    in opposite directions.
+
+[Illustration: A pterygoid plane.]
+
+    _Pterygoid_--That type of the wings of birds which is long and
+    narrow--as distinguished from the apteroid type.
+
+    _Pylon_--A tower-shaped structure used as a derrick (which see);
+    also for displaying signals to aeronauts.
+
+
+R
+
+    _Radial Spoke_--A wire spoke extending from the hub of an
+    alighting wheel straight outward from the centre to the rim of
+    the wheel. See Tangent Spoke.
+
+    _Rarefaction Side_--A correct term for the incorrect “vacuum
+    side,” so-called. The side opposite the compression side: the
+    forward side of a revolving propeller blade, or the upper side
+    of a flying surface, or the side of a rudder-surface turned away
+    from the wind.
+
+    _Reactive Stratum_--The layer of compressed air beneath a moving
+    aeroplane surface, or behind a moving propeller blade.
+
+    _Rib_--The smaller construction members used in building up
+    surfaces. Generally they run fore-and-aft, crossing the spars or
+    wing-bars at right angles, and they are bent to form the curve of
+    the wings or planes.
+
+    _Rising Angle_--Technically, the steepest angle at which any
+    given aeroplane will rise into the air.
+
+    _Rudder_--A movable surface by which the aeronaut is enabled to
+    steer his craft in a desired direction. See Horizontal Rudder and
+    Vertical Rudder.
+
+    _Runner_--A construction similar to the runners of a sleigh, used
+    for alighting on some machines, instead of the wheel alighting
+    gear; a skid.
+
+
+S
+
+    _Screw_--Another term for propeller; properly, screw-propeller.
+
+    _Single-surfaced_--A term used to designate wings or planes
+    whose frames are covered with fabric only on the upper side. See
+    Double-surfaced.
+
+    _Skid_--Another name for runner.
+
+    _Skin Friction_--The retarding effect of the adherence of the
+    air to surfaces moving rapidly through it. It is very slight
+    with polished surfaces, and in case of slow speeds is entirely
+    negligible.
+
+    _Slip_--The difference between the actual progress of a moving
+    propeller, and the theoretical progress expressed by its pitch.
+    It is much greater in some propellers than in others, due to the
+    “churning” of the air by blades of faulty design and construction.
+
+    _Soaring Flight_--The sailing motion in the air achieved by some
+    of the larger birds without the flapping of their wings. It is
+    to be distinguished from gliding in that it is in an upward
+    direction. Soaring has never been satisfactorily explained, and
+    is considered to be the secret whose discovery will bring about
+    the largest advance in the navigation of the air.
+
+    _Spar_--A stick of considerable length used in the framing of the
+    body of aeroplanes, or as the long members in wing structures.
+
+    _Stabilize_--To maintain balance by the automatic action
+    of adjunct surfaces, as distinguished from the intentional
+    manipulation of controlling devices.
+
+    _Stabilizer_--Any surface whose automatic action tends to the
+    maintaining of balance in the air.
+
+    _Stable Equilibrium_--That equilibrium which is inherent in the
+    construction of the machine, and does not depend upon automatic
+    or controlling balancing devices.
+
+    _Starboard_--The right-hand side of an aircraft as one faces
+    forward. See Port.
+
+    _Starting Area_--An area of ground specially prepared to
+    facilitate the starting of aeroplanes into flight.
+
+    _Starting Device_--Any contrivance for giving an aeroplane a
+    powerful impulse or thrust into the air. See Derrick.
+
+    _Starting Impulse_--The thrust with which an aeroplane is started
+    into the air for a flight. Most machines depend upon the thrust
+    of their own propellers, the machine being held back by force
+    until the engines have worked up to flying speed, when it is
+    suddenly released.
+
+    _Starting Rail_--The rail upon which the starting truck runs
+    before the aeroplane rises into the air.
+
+    _Starting Truck_--A small vehicle upon which the aeroplane rests
+    while it is gaining sufficient impulse to take flight.
+
+    _Stay_--A construction member of an aeroplane sustaining a
+    pulling strain. It is usually of wire.
+
+    _Straight Pitch_--That type of pitch (which see) in a propeller
+    blade in which every cross-section of the blade makes the same
+    angle with its axis of revolution.
+
+    _Strainer_--Another term for Turnbuckle--which see.
+
+    _Strut_--An upright, or vertical, construction member of an
+    aeroplane sustaining a compression strain; as distinguished from
+    a brace which sustains a diagonal compression strain.
+
+    _Supplementary Surface_--A comparatively small surface used as an
+    adjunct to the large surfaces for some special purpose; as, for
+    instance, the preserving of balance, or for steering.
+
+    _Sustaining Surface_--The large surfaces of the aeroplane
+    whose rapid movement through the air at a slight angle to the
+    horizontal sustains the weight of the machine.
+
+
+T
+
+    _Tail_--A rear surface on an aeroplane designed to assist in
+    maintaining longitudinal stability. It is in use principally on
+    monoplanes, and is often so arranged as to serve as a rudder.
+
+    _Tail Wheel_--A wheel mounted under the rear end of an aeroplane
+    as a part of the alighting gear.
+
+    _Tangent_--A straight line passing the convex side of a curved
+    line, and touching it at one point only. The straight line is
+    said to be tangent to the curve at the point of contact.
+
+    _Tangential_--In the position or direction of a tangent.
+
+    _Tangent Spoke_--A wire spoke extending from the outer edge of
+    the hub of a wheel along the line of a tangent until it touches
+    the rim. Its position is at right angles to the course of a
+    radial spoke (which see) from the same point on the hub.
+
+    _Tie_--A construction member connecting two points with a pulling
+    strain.
+
+    _Tightener_--A device for taking up the slack of a stay, or tie;
+    as the turnbuckle.
+
+    _Tractor Propeller_--A propeller placed in front, so that it
+    pulls the machine through the air, instead of pushing, or
+    thrusting, it from behind.
+
+    _Triplane_--An aeroplane with three main surfaces, or decks,
+    placed in a tier, one above another.
+
+    _Turnbuckle_--A device with a nut at each end, of contrary pitch,
+    so as to take a right-hand screw at one end, and a left-hand
+    screw at the other; used for drawing together, or toward each
+    other the open ends of a stay, or tie.
+
+
+U
+
+    _Uniform Pitch_--That varying pitch in a propeller blade which
+    causes each point in the blade to move forward in its own circle
+    the same distance in one revolution.
+
+    _Up-wind_--In a direction opposite to the current of the wind;
+    against the wind; in the teeth of the wind.
+
+
+V
+
+    _Vertical Rudder_--A rudder for steering toward right or left; so
+    called because its surface occupies normally a vertical position.
+
+
+W
+
+    _Wake_--The stream of disturbed air left in the rear of a moving
+    aircraft, due mainly to the slip of the propeller.
+
+    _Wash_--The air-currents flowing out diagonally from the sides of
+    a moving aeroplane.
+
+    _Wing Bar_--The larger construction members of a wing, running
+    from the body outward to the tips. The ribs are attached to the
+    wing bars, usually at right angles.
+
+    _Wing Plan_--The outline of the wing or main plane surface as
+    viewed from above.
+
+    _Wing Section_--The outline of the wing structure of an aeroplane
+    as it would appear if cut by a plane passing through it parallel
+    to the longitudinal centre of the machine.
+
+    _Wing Skid_--A small skid, or runner, placed under the tip of
+    the wings of an aeroplane, to prevent damage in case of violent
+    contact with the ground.
+
+    _Wing Tip_--The extreme outer end of a wing or main plane.
+
+    _Wing Warping_--A controlling device for restoring disturbed
+    lateral balance by the forcible pulling down or pulling up of the
+    tips of the wings, or of the outer ends of the main surface of
+    the aeroplane.
+
+    _Wing Wheel_--A small wheel placed under the outer end of a wing
+    or main plane to prevent contact with the ground. An improvement
+    on the wing skid.
+
+
+THE END
+
+
+[Transcriber’s Note:
+
+Inconsistent spelling and hyphenation are as in the original.]
+
+
+
+
+
+End of the Project Gutenberg EBook of How it Flies or, Conquest of the Air, by 
+Richard Ferris
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+
+Project Gutenberg's How it Flies or, Conquest of the Air, by Richard Ferris
+
+This eBook is for the use of anyone anywhere in the United States and most
+other parts of the world at no cost and with almost no restrictions
+whatsoever.  You may copy it, give it away or re-use it under the terms of
+the Project Gutenberg License included with this eBook or online at
+www.gutenberg.org.  If you are not located in the United States, you'll have
+to check the laws of the country where you are located before using this ebook.
+
+Title: How it Flies or, Conquest of the Air
+       The Story of Man's Endeavors to Fly and of the Inventions
+              by which He Has Succeeded
+
+Author: Richard Ferris
+
+Release Date: August 5, 2017 [EBook #55268]
+
+Language: English
+
+Character set encoding: UTF-8
+
+*** START OF THIS PROJECT GUTENBERG EBOOK HOW IT FLIES OR, CONQUEST OF AIR ***
+
+
+
+
+Produced by Chris Curnow, Wayne Hammond and the Online
+Distributed Proofreading Team at http://www.pgdp.net
+
+
+
+
+
+
+</pre>
+
+
+<p><span class="pagenum" id="Page_4">4</span></p>
+
+<div class="figcenter">
+<img src="images/cover.jpg" alt="" />
+</div>
+
+<div class="figcenter">
+<img src="images/frontis.jpg" alt="" />
+<p class="caption">ORVILLE WRIGHT IN THE 80-MILE-AN-HOUR “BABY WRIGHT” RACER.
+<span class="pagenum" id="Page_5">5</span></p></div>
+
+<hr class="chap" />
+
+<h1>
+How It Flies<br />
+
+<small>or,</small><br />
+
+<span class="x-large">THE CONQUEST OF THE AIR</span><br />
+
+<span class="large table">The Story of Man’s Endeavors to Fly and of the<br />
+Inventions by which He Has Succeeded</span><br />
+
+<small>By</small><br />
+
+RICHARD FERRIS, B.S., C.E.<br />
+
+<span class="medium table">Illustrated by Over One Hundred and Fifty Half-tones and Line<br />
+Drawings, Showing the Stages of Development from the<br />
+Earliest Balloon to the Latest Monoplane and Biplane</span><br />
+
+<span class="medium table">New York<br />
+THOMAS NELSON AND SONS<br />
+381-385 Fourth Avenue</span></h1>
+
+<p><span class="pagenum" id="Page_6">6</span></p>
+
+<p class="copy table">Copyright, 1910, by<br />
+
+THOMAS NELSON &amp; SONS</p>
+
+<p class="caption">THE TROW PRESS, NEW YORK
+<span class="pagenum" id="Page_7">7</span></p>
+
+<hr class="chap" />
+
+<h2 id="PREFACE">PREFACE</h2>
+
+<p class="drop"><span class="uppercase">In</span> these pages, by means of simple language and
+suitable pictures, the author has told the story of
+the Ships of the Air. He has explained the laws of
+their flight; sketched their development to the present
+day; shown how to build the flying machine and
+the balloon, and how to operate them; recounted
+what man has done, and what he hopes to do with
+their aid. In a word, all the essential facts that
+enter into the Conquest of the Air have been gathered
+into orderly form, and are here presented to
+the public.</p>
+
+<p>We who live to-day have witnessed man’s great
+achievement; we have seen his dream of ages come
+true. Man has learned to <i>fly</i>!</p>
+
+<p>The air which surrounds us, so intangible and so
+commonplace that it seldom arrests our attention, is
+in reality a vast, unexplored ocean, fraught with
+future possibilities. Even now, the pioneers of a
+<span class="pagenum" id="Page_8">8</span>
+countless fleet are hovering above us in the sky, while
+steadily, surely these wonderful possibilities are
+unfolded.</p>
+
+<p>The Publishers take pleasure in acknowledging
+their indebtedness to the <i>Scientific American</i> for
+their courtesy in permitting the use of many of the
+illustrations appearing in this book.</p>
+
+<p><span class="smcap">New York</span>, October 20, 1910.
+<span class="pagenum" id="Page_9">9</span></p>
+
+<hr class="chap" />
+
+<h2 id="CONTENTS">CONTENTS</h2>
+
+<table>
+  <tr class="small">
+    <td class="tdr">CHAPTER</td>
+    <td />
+    <td class="tdr3">PAGE</td>
+  </tr>
+  <tr>
+    <td />
+    <td><a href="#PREFACE"><span class="smcap">Preface</span></a></td>
+    <td class="tdr3">7</td>
+  </tr>
+  <tr>
+    <td class="tdr">I.</td>
+    <td><a href="#Chapter_I"><span class="smcap">Introductory</span></a></td>
+    <td class="tdr3">11</td>
+  </tr>
+  <tr>
+    <td class="tdr">II.</td>
+    <td><a href="#Chapter_II"><span class="smcap">The Air</span></a></td>
+    <td class="tdr3">20</td>
+  </tr>
+  <tr>
+    <td class="tdr">III.</td>
+    <td><a href="#Chapter_III"><span class="smcap">Laws of Flight</span></a></td>
+    <td class="tdr3">37</td>
+  </tr>
+  <tr>
+    <td class="tdr">IV.</td>
+    <td><a href="#Chapter_IV"><span class="smcap">Flying Machines</span></a></td>
+    <td class="tdr3">55</td>
+  </tr>
+  <tr>
+    <td class="tdr">V.</td>
+    <td><a href="#Chapter_V"><span class="smcap">Flying Machines: The Biplane</span></a></td>
+    <td class="tdr3">78</td>
+  </tr>
+  <tr>
+    <td class="tdr">VI.</td>
+    <td><a href="#Chapter_VI"><span class="smcap">Flying Machines: The Monoplane</span></a></td>
+    <td class="tdr3">112</td>
+  </tr>
+  <tr>
+    <td class="tdr">VII.</td>
+    <td><a href="#Chapter_VII"><span class="smcap">Flying Machines: Other Forms</span></a></td>
+    <td class="tdr3">141</td>
+  </tr>
+  <tr>
+    <td class="tdr">VIII.</td>
+    <td><a href="#Chapter_VIII"><span class="smcap">Flying Machines: How to Operate</span></a></td>
+    <td class="tdr3">151</td>
+  </tr>
+  <tr>
+    <td class="tdr">IX.</td>
+    <td><a href="#Chapter_IX"><span class="smcap">Flying Machines: How to Build</span></a></td>
+    <td class="tdr3">174</td>
+  </tr>
+  <tr>
+    <td class="tdr">X.</td>
+    <td><a href="#Chapter_X"><span class="smcap">Flying Machines: Motors</span></a></td>
+    <td class="tdr3">193</td>
+  </tr>
+  <tr>
+    <td class="tdr">XI.</td>
+    <td><a href="#Chapter_XI"><span class="smcap">Model Flying Machines</span></a></td>
+    <td class="tdr3">215</td>
+  </tr>
+  <tr>
+    <td class="tdr">XII.</td>
+    <td><a href="#Chapter_XII"><span class="smcap">The Glider</span></a></td>
+    <td class="tdr3">241</td>
+  </tr>
+  <tr>
+    <td class="tdr">XIII.</td>
+    <td><a href="#Chapter_XIII"><span class="smcap">Balloons</span></a></td>
+    <td class="tdr3">257<span class="pagenum" id="Page_10">10</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">XIV.</td>
+    <td><a href="#Chapter_XIV"><span class="smcap">Balloons: The Dirigible</span></a></td>
+    <td class="tdr3">296</td>
+  </tr>
+  <tr>
+    <td class="tdr">XV.</td>
+    <td><a href="#Chapter_XV"><span class="smcap">Balloons: How to Operate</span></a></td>
+    <td class="tdr3">340</td>
+  </tr>
+  <tr>
+    <td class="tdr">XVI.</td>
+    <td><a href="#Chapter_XVI"><span class="smcap">Balloons: How to Make</span></a></td>
+    <td class="tdr3">351</td>
+  </tr>
+  <tr>
+    <td class="tdr">XVII.</td>
+    <td><a href="#Chapter_XVII"><span class="smcap">Military Aeronautics</span></a></td>
+    <td class="tdr3">363</td>
+  </tr>
+  <tr>
+    <td class="tdr">XVIII.</td>
+    <td><a href="#Chapter_XVIII"><span class="smcap">Biographies of Prominent Aeronauts</span></a></td>
+    <td class="tdr3">379</td>
+  </tr>
+  <tr>
+    <td class="tdr">XIX.</td>
+    <td><a href="#Chapter_XIX"><span class="smcap">Chronicle of Aviation Achievements</span></a></td>
+    <td class="tdr3">407</td>
+  </tr>
+  <tr>
+    <td class="tdr">XX.</td>
+    <td><a href="#Chapter_XX"><span class="smcap">Explanation of Aeronautical Terms</span></a></td>
+    <td class="tdr3">452</td>
+  </tr></table>
+
+<hr class="chap" />
+
+<p><span class="pagenum" id="Page_11">11</span></p>
+
+<h2 class="xx-large" id="HOW_IT_FLIES">HOW IT FLIES</h2>
+
+<hr class="chap" />
+<h2 id="Chapter_I">Chapter I.<br />
+
+INTRODUCTORY.</h2>
+
+<blockquote>
+
+<p>The sudden awakening&mdash;Early successes&mdash;Influence of the gasoline
+engine on aeroplanes&mdash;On dirigible balloons&mdash;Interested
+inquiry&mdash;Some general terms defined.</p></blockquote>
+
+<p class="drop"><span class="uppercase">In</span> the year 1908 the world awakened suddenly to
+the realization that at last the centuries of man’s
+endeavor to fly mechanically had come to successful
+fruition.</p>
+
+<p>There had been a little warning. In the late
+autumn of 1906, Santos-Dumont made a flight of
+720 feet in a power-driven machine. There was an
+exclamation of wonder, a burst of applause&mdash;then a
+relapse into unconcern.</p>
+
+<p>In August, 1907, Louis Bleriot sped free of the
+ground for 470 feet; and in November, Santos-Dumont
+made two flying leaps of barely 500 feet.
+That was the year’s record, and it excited little comment.
+It is true that the Wright brothers had been
+<span class="pagenum" id="Page_12">12</span>
+making long flights, but they were in secret. There
+was no public knowledge of them.</p>
+
+<p>In 1908 came the revelation. In March, Delagrange
+flew in a Voisin biplane 453 feet, carrying
+Farman with him as a passenger. Two weeks later
+he flew alone nearly 2½ miles. In May he flew
+nearly 8 miles. In June his best flight was 10½
+miles. Bleriot came on the scene again in July with
+a monoplane, in which he flew 3¾ miles. In September,
+Delagrange flew 15 miles&mdash;in less than 30 minutes.
+In the same month the Wrights began their
+wonderful public flights. Wilbur, in France, made
+records of 41, 46, 62, and 77 miles, while Orville
+flew from 40 to 50 miles at Fort Myer, Va. Wilbur
+Wright’s longest flight kept him in the air 2 hours
+and 20 minutes.</p>
+
+<p>The goal had been reached&mdash;men had achieved the
+apparently impossible. The whole world was roused
+to enthusiasm.</p>
+
+<p>Since then, progress has been phenomenally rapid,
+urged on by the striving of the inventors, the competition
+of the aircraft builders, and the contests for
+records among the pilots.</p>
+
+<p>By far the largest factor in the triumph of the
+aeroplane is the improved gasoline engine, designed
+<span class="pagenum" id="Page_13">13</span>
+originally for automobiles. Without this wonderful
+type of motor, delivering a maximum of power with
+a minimum of weight, from concentrated fuel, the
+flying machine would still be resting on the earth.</p>
+
+<div class="figcenter">
+<img src="images/i_013.jpg" alt="" />
+<p class="caption">The Renard and Krebs airship <i>La France</i>, at Chalais-Meudon.</p></div>
+
+<p>Nor has the influence of the gasoline motor been
+much less upon that other great class of aircraft, the
+dirigible balloon. After 1885, when Renard and
+Krebs’ airship <i>La France</i> made its two historic
+voyages from Chalais-Meudon to Paris, returning
+safely to its shed, under the propulsion of an electric
+motor, the problem of the great airship lay dormant,
+waiting for the discovery of adequate motive power.
+If the development of the dirigible balloon seems
+<span class="pagenum" id="Page_14">14</span>
+less spectacular than that of the aeroplane, it is
+because the latter had to be created; the dirigible,
+already in existence, had only to be revivified.</p>
+
+<p>Confronted with these new and strange shapes in
+the sky, some making stately journeys of hundreds
+of miles, others whirring hither and thither with the
+speed of the whirlwind, wonder quickly gives way
+to the all-absorbing question: <i>How do they fly?</i> To
+answer fully and satisfactorily, it seems wise, for
+many readers, to recall in the succeeding chapters
+some principles doubtless long since forgotten.</p>
+
+<hr class="tb" />
+
+<p>As with every great advance in civilization, this
+expansion of the science of aeronautics has had its
+effect upon the language of the day. Terms formerly
+in use have become restricted in application, and
+other terms have been coined to convey ideas so entirely
+new as to find no suitable word existent in our
+language. It seems requisite, therefore, first to acquaint
+the reader with clear definitions of the more
+common terms that are used throughout this book.</p>
+
+<p><i>Aeronautics</i> is the word employed to designate the
+entire subject of aerial navigation. An <i>aeronaut</i> is
+a person who sails, or commands, any form of aircraft,
+as distinguished from a passenger.
+<span class="pagenum" id="Page_15">15</span></p>
+
+<p><i>Aviation</i> is limited to the subject of flying by machines
+which are not floated in the air by gas. An
+<i>aviator</i> is an operator of such machine.</p>
+
+<div class="figcenter">
+<img src="images/i_015.jpg" alt="" />
+<p class="caption">A free balloon, with parachute.</p></div>
+
+<p>Both aviators and aeronauts are often called
+<i>pilots</i>.</p>
+
+<p>A <i>balloon</i> is essentially an envelope or bag filled
+<span class="pagenum" id="Page_16">16</span>
+with some gaseous substance which is lighter, bulk
+for bulk, than the air at the surface of the earth, and
+which serves to float the apparatus in the air. In its
+usual form it is spherical, with a car or basket suspended
+below it. It is a <i>captive balloon</i> if it is attached
+to the ground by a cable, so that it may not
+rise above a certain level, nor float away in the wind.
+It is a <i>free balloon</i> if not so attached or anchored,
+but is allowed to drift where the wind may carry it,
+rising and falling at the will of the pilot.</p>
+
+<div class="figcenter">
+<img src="images/i_016.jpg" alt="" />
+<p class="caption">A dirigible balloon.</p></div>
+
+<p>A <i>dirigible balloon</i>, sometimes termed simply a
+dirigible, usually has its gas envelope elongated in
+form. It is fitted with motive power to propel it,
+<span class="pagenum" id="Page_17">17</span>
+and steering mechanism to guide it. It is distinctively
+the <i>airship</i>.</p>
+
+<p><i>Aeroplanes</i> are those forms of flying machines
+which depend for their support in the air upon the
+spread of surfaces which are variously called wings,
+sails, or planes. They are commonly driven by propellers
+actuated by motors. When not driven by
+power they are called <i>gliders</i>.</p>
+
+<div class="figcenter">
+<img src="images/i_017.jpg" alt="" />
+<p class="caption">A biplane glider.</p></div>
+
+<p>Aeroplanes exist in several types: the <i>monoplane</i>,
+with one spread of surface; the <i>biplane</i>, with two
+spreads, one above the other; the <i>triplane</i>, with three
+spreads, or decks; the <i>multiplane</i>, with more than
+three.
+<span class="pagenum" id="Page_18">18</span></p>
+
+<p>The <i>tetrahedral plane</i> is a structure of many small
+cells set one upon another.</p>
+
+<p><i>Ornithopter</i> is the name given to a flying machine
+which is operated by flapping wings.</p>
+
+<div class="figcenter">
+<img src="images/i_018.jpg" alt="" />
+<p class="caption">A parachute descending.</p></div>
+
+<p><i>Helicopter</i> is used to designate machines which
+are lifted vertically and sustained in the air by propellers
+revolving in a horizontal plane, as distinguished
+from the propellers of the aeroplane, which
+revolve in vertical planes.
+<span class="pagenum" id="Page_19">19</span></p>
+
+<p>A <i>parachute</i> is an umbrella-like contrivance by
+which an aeronaut may descend gently from a balloon
+in mid-air, buoyed up by the compression of the
+air under the umbrella.</p>
+
+<p>For the definition of other and more technical
+terms the reader is referred to the carefully prepared
+Glossary toward the end of the book.
+<span class="pagenum" id="Page_20">20</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_II">Chapter II.<br />
+
+THE AIR.</h2>
+
+<blockquote>
+
+<p>Intangibility of air&mdash;Its substance&mdash;Weight&mdash;Extent&mdash;Density&mdash;Expansion
+by heat&mdash;Alcohol fire&mdash;Turbulence of the air&mdash;Inertia&mdash;Elasticity&mdash;Viscosity&mdash;Velocity
+of winds&mdash;Aircurrents&mdash;Cloud
+levels&mdash;Aerological stations&mdash;High altitudes&mdash;Practical
+suggestions&mdash;The ideal highway.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> air about us seems the nearest approach to
+nothingness that we know of. A pail is commonly
+said to be empty&mdash;to have nothing in it&mdash;when
+it is filled only with air. This is because our
+senses do not give us any information about air. We
+cannot see it, hear it, touch it.</p>
+
+<p>When air is in motion (wind) we hear the noises
+it makes as it passes among other objects more substantial;
+and we feel it as it blows by us, or when we
+move rapidly through it.</p>
+
+<p>We get some idea that it exists as a substance
+when we see dead leaves caught up in it and whirled
+about; and, more impressively, when in the violence
+of the hurricane it seizes upon a body of great size
+<span class="pagenum" id="Page_21">21</span>
+and weight, like the roof of a house, and whisks it
+away as though it were a feather, at a speed exceeding
+that of the fastest railroad train.</p>
+
+<p>In a milder form, this invisible and intangible air
+does some of our work for us in at least two ways
+that are conspicuous: it moves ships upon the ocean,
+and it turns a multitude of windmills, supplying the
+cheapest power known.</p>
+
+<p>That this atmosphere is really a fluid ocean, having
+a definite substance, and in some respects resembling
+the liquid ocean upon which our ships sail, and
+that we are only crawling around on the bottom of
+it, as it were, is a conception we do not readily
+grasp. Yet this conception must be the foundation
+of every effort to sail, to fly, in this aerial ocean, if
+such efforts are to be crowned with success.</p>
+
+<p>As a material substance the air has certain physical
+properties, and it is the part of wisdom for the
+man who would fly to acquaint himself with these
+properties. If they are helpful to his flight, he wants
+to use them; if they hinder, he must contrive to overcome
+them.</p>
+
+<p>In general, it may be said that the air, being in
+a gaseous form, partakes of the properties of all gases&mdash;and
+these may be studied in any text-book on
+<span class="pagenum" id="Page_22">22</span>
+physics, Here we are concerned only with those
+qualities which affect conditions under which we
+strive to fly.</p>
+
+<p>Of first importance is the fact that air has <i>weight</i>.
+That is, in common with all other substances, it is
+attracted by the mass of the earth exerted through
+the force we call gravity. At the level of the sea,
+this attraction causes the air to press upon the earth
+with a weight of nearly fifteen pounds (accurately,
+14.7 lbs.) to the square inch, when the temperature
+is at 32° F. That pressure is the weight of a column
+of air one inch square at the base, extending upward
+to the outer limit of the atmosphere&mdash;estimated to
+be about 38 miles (some say 100 miles) above sea-level.
+The practical fact is that normal human
+life cannot exist above the level of 15,000 feet,
+or a little less than three miles; and navigation
+of the air will doubtless be carried on at a much
+lower altitude, for reasons which will appear as we
+continue.</p>
+
+<p>The actual weight of a definite quantity of dry
+air&mdash;for instance, a cubic foot&mdash;is found by weighing
+a vessel first when full of air, and again after the
+air has been exhausted from it with an air-pump. In
+this way it has been determined that a cubic foot of
+<span class="pagenum" id="Page_23">23</span>
+<span class="pagenum" id="Page_24">24</span>
+dry air, at the level of the sea, and at a temperature
+of 32° F., weighs 565 grains&mdash;about 0.0807 lb. At a
+height above the level of the sea, a cubic foot of air
+will weigh less than the figure quoted, for its density
+decreases as we go upward, the pressure being less
+owing to the diminished attraction of the earth at
+the greater distance. For instance, at the height of
+a mile above sea-level a cubic foot of air will weigh
+about 433 grains, or 0.0619 lb. At the height of
+five miles it will weigh about 216 grains, or 0.0309
+lb. At thirty-eight miles it will have no weight at
+all, its density being so rare as just to balance the
+earth’s attraction. It has been calculated that the
+whole body of air above the earth, if it were all of
+the uniform density of that at sea-level, would extend
+only to the height of 26,166 feet. Perhaps a
+clearer comprehension of the weight and pressure of
+the ocean of air upon the earth may be gained by
+recalling that the pressure of the 38 miles of atmosphere
+is just equal to balancing a column of water
+33 feet high. The pressure of the air, therefore, is
+equivalent to the pressure of a flood of water 33 feet
+deep.</p>
+
+<div class="figcenter">
+<img src="images/i_023.jpg" alt="" />
+<p class="caption">Comparative Elevations of Earth and Air.</p></div>
+
+<p>But air is seldom dry. It is almost always mingled
+with the vapor of water, and this vapor weighs
+<span class="pagenum" id="Page_25">25</span>
+only 352 grains per cubic foot at sea-level. Consequently
+the mixture&mdash;damp air&mdash;is lighter than dry
+air, in proportion to the moisture it contains.</p>
+
+<div class="figcenter">
+<img src="images/i_025.jpg" alt="" />
+<p class="caption">Apparatus to show effects of heat on air currents. <i>a</i>, alcohol lamp;
+<i>b</i>, ice. The arrows show direction of currents.</p></div>
+
+<p>Another fact very important to the aeronaut is
+that the air is in <i>constant motion</i>. Owing to its
+ready expansion by heat, a body of air occupying one
+<span class="pagenum" id="Page_26">26</span>
+cubic foot when at a temperature of 32° F. will
+occupy more space at a higher temperature, and less
+space at a lower temperature. Hence, heated air will
+flow upward until it reaches a point where the natural
+density of the atmosphere is the same as its expanded
+density due to the heating. Here another
+complication comes into play, for ascending air is
+cooled at the rate of one degree for every 183 feet it
+rises; and as it cools it grows denser, and the speed
+of its ascension is thus gradually checked. After
+passing an altitude of 1,000 feet the decrease in temperature
+is one degree for each 320 feet of ascent.
+In general, it may be stated that air is expanded one-tenth
+of its volume for each 50° F. that its temperature
+is raised.</p>
+
+<p>This highly unstable condition under ordinary
+changes of temperature causes continual movements
+in the air, as different portions of it are constantly
+seeking that position in the atmosphere where their
+density at that moment balances the earth’s attraction.</p>
+
+<p>Sir Hiram Maxim relates an incident which aptly
+illustrates the effect of change of temperature upon
+the air. He says: “On one occasion, many years
+ago, I was present when a bonded warehouse in
+<span class="pagenum" id="Page_27">27</span>
+New York containing 10,000 barrels of alcohol was
+burned.... I walked completely around the fire,
+and found things just as I expected. The wind was
+blowing a perfect hurricane through every street in
+the direction of the fire, although it was a dead calm
+everywhere else; the flames mounted straight in the
+air to an enormous height, and took with them a
+large amount of burning wood. When I was fully
+500 feet from the fire, a piece of partly burned one-inch
+board, about 8 inches wide and 4 feet long, fell
+through the air and landed near me. This board had
+evidently been taken up to a great height by the
+tremendous uprush of air caused by the burning
+alcohol.”</p>
+
+<p>That which happened on a small scale, with a violent
+change of temperature, in the case of the alcohol
+fire, is taking place on a larger scale, with milder
+changes in temperature, all over the world. The
+heating by the sun in one locality causes an expansion
+of air at that place, and cooler, denser air rushes
+in to fill the partial vacuum. In this way winds are
+produced.</p>
+
+<p>So the air in which we are to fly is in a state of
+constant motion, which may be likened to the rush
+and swirl of water in the rapids of a mountain torrent.
+<span class="pagenum" id="Page_28">28</span>
+The tremendous difference is that the perils
+of the water are in plain sight of the navigator, and
+may be guarded against, while those of the air are
+wholly invisible, and must be met as they occur,
+without a moment’s warning.</p>
+
+<div class="figcenter">
+<img src="images/i_028.jpg" alt="" />
+<blockquote>
+
+<p>The solid arrows show the directions of a cyclonic wind on the earth’s surface.
+At the centre the currents go directly upward. In the upper air above the
+cyclone the currents have the directions of the dotted arrows.</p></blockquote>
+</div>
+
+<p>Next in importance, to the aerial navigator, is the
+air’s <i>resistance</i>. This is due in part to its density at
+the elevation at which he is flying, and in part to the
+direction and intensity of its motion, or the wind.
+<span class="pagenum" id="Page_29">29</span>
+While this resistance is far less than that of water
+to the passage of a ship, it is of serious moment to
+the aeronaut, who must force his fragile machine
+through it at great speed, and be on the alert every
+instant to combat the possibility of a fall as he passes
+into a rarer and less buoyant stratum.</p>
+
+<div class="figcenter">
+<img src="images/i_029.jpg" alt="" />
+<blockquote>
+
+<p>Diagram showing disturbance of wind currents by inequalities of the ground,
+and the smoother currents of the upper air. Note the increase of density
+at A and B, caused by compression against the upper strata.</p></blockquote>
+</div>
+
+<p>Three properties of the air enter into the sum total
+of its resistance&mdash;inertia, elasticity, and viscosity.
+Inertia is its tendency to remain in the condition in
+which it may be: at rest, if it is still; in motion, if
+it is moving. Some force must be applied to disturb
+this inertia, and in consequence when the inertia is
+overcome a certain amount of force is used up in the
+<span class="pagenum" id="Page_30">30</span>
+operation. Elasticity is that property by virtue of
+which air tends to reoccupy its normal amount of
+space after disturbance. An illustration of this tendency
+is the springing back of the handle of a bicycle
+pump if the valve at the bottom is not open, and the
+air in the pump is simply compressed, not forced into
+the tire. Viscosity may be described as “stickiness”&mdash;the
+tendency of the particles of air to cling together,
+to resist separation. To illustrate: molasses,
+particularly in cold weather, has greater viscosity
+than water; varnish has greater viscosity than turpentine.
+Air exhibits some viscosity, though vastly
+less than that of cold molasses. However, though
+relatively slight, this viscosity has a part in the resistance
+which opposes the rapid flight of the airship
+and aeroplane; and the higher the speed, the greater
+the retarding effect of viscosity.</p>
+
+<p>The inertia of the air, while in some degree it
+blocks the progress of his machine, is a benefit to the
+aeronaut, for it is inertia which gives the blades of
+his propeller “hold” upon the air. The elasticity of
+the air, compressed under the curved surfaces of the
+aeroplane, is believed to be helpful in maintaining
+the lift. The effect of viscosity may be greatly reduced
+by using surfaces finished with polished varnish&mdash;just
+<span class="pagenum" id="Page_31">31</span>
+as greasing a knife will permit it to be
+passed with less friction through thick molasses.</p>
+
+<p>In the case of winds, the inertia of the moving
+mass becomes what is commonly termed “wind pressure”
+against any object not moving with it at an
+equal speed. The following table gives the measurements
+of wind pressure, as recorded at the station on
+the Eiffel Tower, for differing velocities of wind:</p>
+
+<table id="velocity" class="bbox">
+  <tr>
+    <th>Velocity<br />in Miles<br />per Hour</th>
+    <th>Velocity<br />in Feet<br />per Second</th>
+    <th>Pressure <br />in Pounds on<br />a Square Foot</th>
+  </tr>
+  <tr>
+    <td>2</td>
+    <td class="decimal"><span class="right">2</span>.<span class="left">9</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">012</span></td>
+  </tr>
+  <tr>
+    <td>4</td>
+    <td class="decimal"><span class="right">5</span>.<span class="left">9</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">048</span></td>
+  </tr>
+  <tr>
+    <td>6</td>
+    <td class="decimal"><span class="right">8</span>.<span class="left">8</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">108</span></td>
+  </tr>
+  <tr>
+    <td>8</td>
+    <td class="decimal"><span class="right">11</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">192</span></td>
+  </tr>
+  <tr>
+    <td>10</td>
+    <td class="decimal"><span class="right">14</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">300</span></td>
+  </tr>
+  <tr>
+    <td>15</td>
+    <td class="decimal"><span class="right">22</span>.<span class="left">0</span></td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">675</span></td>
+  </tr>
+  <tr>
+    <td>20</td>
+    <td class="decimal"><span class="right">29</span>.<span class="left">4</span></td>
+    <td class="decimal"><span class="right">1</span>.<span class="left">200</span></td>
+  </tr>
+  <tr>
+    <td>25</td>
+    <td class="decimal"><span class="right">36</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">1</span>.<span class="left">875</span></td>
+  </tr>
+  <tr>
+    <td>30</td>
+    <td class="decimal"><span class="right">44</span>.<span class="left">0</span></td>
+    <td class="decimal"><span class="right">2</span>.<span class="left">700</span></td>
+  </tr>
+  <tr>
+    <td>35</td>
+    <td class="decimal"><span class="right">51</span>.<span class="left">3</span></td>
+    <td class="decimal"><span class="right">3</span>.<span class="left">675</span></td>
+  </tr>
+  <tr>
+    <td>40</td>
+    <td class="decimal"><span class="right">58</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">4</span>.<span class="left">800</span></td>
+  </tr>
+  <tr>
+    <td>45</td>
+    <td class="decimal"><span class="right">66</span>.<span class="left">0</span></td>
+    <td class="decimal"><span class="right">6</span>.<span class="left">075</span></td>
+  </tr>
+  <tr>
+    <td>50</td>
+    <td class="decimal"><span class="right">73</span>.<span class="left">4</span></td>
+    <td class="decimal"><span class="right">7</span>.<span class="left">500</span></td>
+  </tr>
+  <tr>
+    <td>60</td>
+    <td class="decimal"><span class="right">88</span>.<span class="left">0</span></td>
+    <td class="decimal"><span class="right">10</span>.<span class="left">800</span></td>
+  </tr>
+  <tr>
+    <td>70</td>
+    <td class="decimal"><span class="right">102</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">14</span>.<span class="left">700</span></td>
+  </tr>
+  <tr>
+    <td>80</td>
+    <td class="decimal"><span class="right">117</span>.<span class="left">2</span></td>
+    <td class="decimal"><span class="right">19</span>.<span class="left">200</span></td>
+  </tr>
+  <tr>
+    <td>90</td>
+    <td class="decimal"><span class="right">132</span>.<span class="left">0</span></td>
+    <td class="decimal"><span class="right">24</span>.<span class="left">300</span></td>
+  </tr>
+  <tr>
+    <td>100</td>
+    <td class="decimal"><span class="right">146</span>.<span class="left">7</span></td>
+    <td class="decimal"><span class="right">30</span>.<span class="left">000</span></td>
+  </tr>
+</table>
+
+<p>In applying this table, the velocity to be considered
+is the net velocity of the movements of the airship
+<span class="pagenum" id="Page_32">32</span>
+and of the wind. If the ship is moving 20 miles
+an hour <i>against</i> a head wind blowing 20 miles an
+hour, the net velocity of the wind will be 40 miles an
+hour, and the pressure 4.8 lbs. a square foot of surface
+presented. Therefore the airship will be standing
+still, so far as objects on the ground are concerned.
+If the ship is sailing 20 miles an hour <i>with</i>
+the wind, which is blowing 20 miles an hour, the
+pressure per square foot will be only 1.2 lbs.; while
+as regards objects on the ground, the ship will be
+travelling 40 miles an hour.</p>
+
+<div class="figcenter">
+<img src="images/i_032.jpg" alt="" />
+<blockquote>
+
+<p>Apparatus for the study of the action of air in motion; a blower at the farther
+end of the great tube sends a “wind” of any desired velocity through it.
+Planes and propellers of various forms are thus tested.</p></blockquote>
+</div>
+
+<p><span class="pagenum" id="Page_33">33</span></p>
+
+<p>Systematic study of the movements of the air
+currents has not been widespread, and has not progressed
+much beyond the gathering of statistics which
+may serve as useful data in testing existing theories
+or formulating new ones.</p>
+
+<p>It is already recognized that there are certain
+“tides” in the atmosphere, recurring twice daily in
+six-hour periods, as in the case of the ocean tides,
+and perhaps from the same causes. Other currents
+are produced by the earth’s rotation. Then there
+are the five-day oscillations noted by Eliot in India,
+and daily movements, more or less regular, due to the
+sun’s heat by day and the lack of it by night. The
+complexity of these motions makes scientific research
+extremely difficult.</p>
+
+<p>Something definite has been accomplished in the
+determination of wind velocities, though this varies
+largely with the locality. In the United States the
+average speed of the winds is 9½ miles per hour; in
+Europe, 10⅓ miles; in Southern Asia, 6½ miles; in
+the West Indies, 6⅕ miles; in England, 12 miles;
+over the North Atlantic Ocean, 29 miles per hour.
+Each of these average velocities varies with the time
+of year and time of day, and with the distance
+from the sea. The wind moves faster over water
+<span class="pagenum" id="Page_34">34</span>
+and flat, bare land than over hilly or forest-covered
+areas. Velocities increase as we go upward in the
+air, being at 1,600 feet twice what they are at 100
+feet. Observations of the movements of cloud forms
+at the Blue Hill Observatory, near Boston, give the
+following results:</p>
+
+<table id="cloudform" class="bbox">
+  <tr>
+    <th>Cloud Form</th>
+    <th>Height<br />in Feet</th>
+    <th>Average Speed<br />per Hour</th>
+  </tr>
+  <tr>
+    <td>Stratus</td>
+    <td>1,676</td>
+    <td>19 miles.</td>
+  </tr>
+  <tr>
+    <td>Cumulus</td>
+    <td>5,326</td>
+    <td>24 miles.</td>
+  </tr>
+  <tr>
+    <td>Alto-cumulus</td>
+    <td>12,724</td>
+    <td>34 miles.</td>
+  </tr>
+  <tr>
+    <td>Cirro-cumulus</td>
+    <td>21,888</td>
+    <td>71 miles.</td>
+  </tr>
+  <tr>
+    <td>Cirrus</td>
+    <td>29,317</td>
+    <td>78 miles.</td>
+  </tr>
+</table>
+
+<p>In winter the speed of cirrus clouds may reach
+96 miles per hour.</p>
+
+<p>There are forty-nine stations scattered over Germany
+where statistics concerning winds are gathered
+expressly for the use of aeronauts. At many of these
+stations records have been kept for twenty years.
+Dr. Richard Assman, director of the aerological observatory
+at Lindenburg, has prepared a comprehensive
+treatise of the statistics in possession of these
+stations, under the title of <i>Die Winde in Deutschland</i>.
+It shows for each station, and for each season
+of the year, how often the wind blows from each
+<span class="pagenum" id="Page_35">35</span>
+point of the compass; the average frequency of the
+several degrees of wind; when and where aerial voyages
+may safely be made; the probable drift of dirigibles,
+etc. It is interesting to note that Friedrichshafen,
+where Count Zeppelin’s great airship sheds
+are located, is not a favorable place for such vessels,
+having a yearly record of twenty-four stormy days,
+as compared with but two stormy days at Celle, four
+at Berlin, four at Cassel, and low records at several
+other points.</p>
+
+<p>In practical aviation, a controlling factor is the
+density of the air. We have seen that at an altitude
+of five miles the density is about three-eighths the
+density at sea-level. This means that the supporting
+power of the air at a five-mile elevation is so small
+that the area of the planes must be increased to more
+than 2½ times the area suited to flying near the
+ground, or that the speed must be largely increased.
+Therefore the adjustments necessary for rising at the
+lower level and journeying in the higher level are too
+large and complex to make flying at high altitudes
+practicable&mdash;leaving out of consideration the bitter
+cold of the upper regions.</p>
+
+<p>Mr. A. Lawrence Rotch, director of the Blue Hill
+Observatory, in his valuable book, <i>The Conquest of</i>
+<span class="pagenum" id="Page_36">36</span>
+<i>the Air</i>, gives this practical summary of a long
+series of studious observations: “At night, however,
+because there are no ascending currents, the wind is
+much steadier than in the daytime, making night the
+most favorable time for aerial navigation of all
+kinds.... A suitable height in the daytime, unless
+a strong westerly wind is sought, lies above the cumulus
+clouds, at the height of about a mile; but at night
+it is not necessary to rise so high; and in summer a
+region of relatively little wind is found at a height of
+about three-fourths of a mile, where it is also warmer
+and drier than in the daytime or at the ground.”</p>
+
+<p>Notwithstanding all difficulties, the fact remains
+that, once they are overcome, the air is the ideal highway
+for travel and transportation. On the sea, a
+ship may sail to right or left on one plane only. In
+the air, we may steer not only to right or left, but
+above and below, and obliquely in innumerable planes.
+We shall not need to traverse long distances in a
+wrong direction to find a bridge by which we may
+cross a river, nor zigzag for toilsome miles up the
+steep slopes of a mountain-side to the pass where we
+may cross the divide. The course of the airship is
+the proverbial bee-line&mdash;the most economical in time
+as well as in distance.
+<span class="pagenum" id="Page_37">37</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_III">Chapter III.<br />
+
+LAWS OF FLIGHT.</h2>
+
+<blockquote>
+
+<p>The bird&mdash;Nature’s models&mdash;Man’s methods&mdash;Gravity&mdash;The balloon&mdash;The
+airship&mdash;Resistance of the air&mdash;Winds&mdash;The
+kite&mdash;Laws of motion and force&mdash;Application to kite-flying&mdash;Aeroplanes.</p></blockquote>
+
+<p class="drop"><span class="uppercase">If</span> we were asked to explain the word “flying” to
+some foreigner who did not know what it meant,
+we should probably give as an illustration the bird.
+This would be because the bird is so closely associated
+in our thoughts with flying that we can hardly
+think of the one without the other.</p>
+
+<p>It is natural, therefore, that since men first had
+the desire to fly they should study the form and motions
+of the birds in the air, and try to copy them.
+Our ancestors built immense flopping wings, into the
+frames of which they fastened themselves, and with
+great muscular exertion of arms and legs strove to
+attain the results that the bird gets by apparently
+similar motions.</p>
+
+<p>However, this mental coupling of the bird with
+<span class="pagenum" id="Page_38">38</span>
+the laws of flight has been unfortunate for the
+achievement of flight by man. And this is true even
+to the present day, with its hundreds of successful
+flying machines that are not in the least like a bird.
+This wrongly coupled idea is so strong that scientific
+publications print pages of research by eminent contributors
+into the flight of birds, with the attempt to
+deduce lessons therefrom for the instruction of the
+builders and navigators of flying machines.</p>
+
+<p>These arguments are based on the belief that
+Nature never makes a mistake; that she made the
+bird to fly, and therefore the bird must be the most
+perfect model for the successful flying machine. But
+the truth is, the bird was not made primarily to fly,
+any more than man was made to walk. Flying is an
+incident in the life of a bird, just as walking is an
+incident in the life of a man. Flying is simply a
+bird’s way of getting about from place to place, on
+business or on pleasure, as the case may be.</p>
+
+<p>Santos-Dumont, in his fascinating book, <i>My Air-Ships</i>,
+points out the folly of blindly following Nature
+by showing that logically such a procedure
+would compel us to build our locomotives on the plan
+of gigantic horses, with huge iron legs which would
+go galloping about the country in a ridiculously terrible
+<span class="pagenum" id="Page_39">39</span>
+fashion; and to construct our steamships on the
+plan of giant whales, with monstrous flapping fins
+and wildly lashing tails.</p>
+
+<p>Sir Hiram Maxim says something akin to this in
+his work, <i>Artificial and Natural Flight</i>: “It appears
+to me that there is nothing in Nature which is
+more efficient, or gets a better grip on the water, than
+a well-made screw propeller; and no doubt there
+would have been fish with screw propellers, providing
+Dame Nature could have made an animal in two
+pieces. It is very evident that no living creature
+could be made in two pieces, and two pieces are
+necessary if one part is stationary and the other revolves;
+however, the tails and fins very often approximate
+to the action of propeller blades; they
+turn first to the right and then to the left, producing
+a sculling effect which is practically the same. This
+argument might also be used against locomotives. In
+all Nature we do not find an animal travelling on
+wheels, but it is quite possible that a locomotive
+might be made that would walk on legs at the rate
+of two or three miles an hour. But locomotives with
+wheels are able to travel at least three times as fast
+as the fleetest animal with legs, and to continue
+doing so for many hours at a time, even when attached
+<span class="pagenum" id="Page_40">40</span>
+to a very heavy load. In order to build a flying
+machine with flapping wings, to exactly imitate
+birds, a very complicated system of levers, cams,
+cranks, etc., would have to be employed, and these of
+themselves would weigh more than the wings would
+be able to lift.”</p>
+
+<p>As with the man-contrived locomotive, so the perfected
+airship will be evolved from man’s understanding
+of the obstacles to his navigation of the air,
+and his overcoming of them by his inventive genius.
+This will not be in Nature’s way, but in man’s own
+way, and with cleverly designed machinery such as
+he has used to accomplish other seeming impossibilities.
+With the clearing up of wrong conceptions, the
+path will be open to more rapid and more enduring
+progress.</p>
+
+<p>When we consider the problem of flying, the first
+obstacle we encounter is the attraction which the
+earth has for us and for all other objects on its surface.
+This we call weight, and we are accustomed
+to measure it in pounds.</p>
+
+<p>Let us take, for example, a man whose body is attracted
+by the earth with a force, or weight, of 150
+pounds. To enable him to rise into the air, means
+must be contrived not only to counteract his weight,
+<span class="pagenum" id="Page_41">41</span>
+but to lift him&mdash;a force a little greater than 150
+pounds must be exerted. We may attach to him a
+bag filled with some gas (as hydrogen) for which the
+earth has less attraction than it has for air, and which
+the air will push out of the way and upward until a
+place above the earth is reached where the attraction
+of air and gas is equal. A bag of this gas large
+enough to be pushed upward with a force equal to
+the weight of the man, plus the weight of the bag,
+and a little more for lifting power, will carry the
+man up. This is the principle of the ordinary
+balloon.</p>
+
+<p>Rising in the air is not flying. It is a necessary
+step, but real flying is to travel from place to place
+through the air. To accomplish this, some mechanism,
+or machinery, is needed to propel the man after
+he has been lifted into the air. Such machinery will
+have weight, and the bag of gas must be enlarged to
+counterbalance it. When this is done, the man and
+the bag of gas may move through the air, and with
+suitable rudders he may direct his course. This combination
+of the lifting bag of gas and the propelling
+machinery constitutes the dirigible balloon, or airship.</p>
+
+<div class="figcenter">
+<img src="images/i_042.jpg" alt="" />
+<p class="caption">Degen’s apparatus to lift the man and his flying mechanism with the aid of
+a gas-balloon. See <a href="#Chapter_IV">Chapter IV</a>.</p></div>
+
+<p>The airship is affected equally with the balloon by
+<span class="pagenum" id="Page_42">42</span>
+prevailing winds. A breeze blowing 10 miles an
+hour will carry a balloon at nearly that speed in the
+direction in which it is blowing. Suppose the aeronaut
+wishes to sail in the opposite direction? If the
+<span class="pagenum" id="Page_43">43</span>
+machinery will propel his airship only 10 miles an
+hour in a calm, it will virtually stand still in the
+10-mile breeze. If the machinery will propel his
+airship 20 miles an hour in a calm, the ship will
+travel 10 miles an hour&mdash;as related to places on the
+earth’s surface&mdash;against the wind. But so far as the
+air is concerned, his speed through it is 20 miles
+an hour, and each increase of speed meets increased
+resistance from the air, and requires a greater expenditure
+of power to overcome. To reduce this resistance
+to the least possible amount, the globular
+form of the early balloon has been variously modified.
+Most modern airships have a “cigar-shaped”
+gas bag, so called because the ends look like the tip
+of a cigar. As far as is known, this is the balloon
+that offers less resistance to the air than any other.</p>
+
+<p>Another mechanical means of getting up into the
+air was suggested by the flying of kites, a pastime
+dating back at least 2,000 years, perhaps longer.
+Ordinarily, a kite will not fly in a calm, but with
+even a little breeze it will mount into the air by the
+upward thrust of the rushing breeze against its inclined
+surface, being prevented from blowing away
+(drifting) by the pull of the kite-string. The same
+effect will be produced in a dead calm if the operator,
+<span class="pagenum" id="Page_44">44</span>
+holding the string, runs at a speed equal to that
+of the breeze&mdash;with this important difference: not
+only will the kite rise in the air, but it will travel
+in the direction in which the operator is running, a
+part of the energy of the runner’s pull upon the
+string producing a forward motion, provided he
+holds the string taut. If we suppose the pull on the
+string to be replaced by an engine and revolving propeller
+in the kite, exerting the same force, we have
+exactly the principle of the aeroplane.</p>
+
+<p>As it is of the greatest importance to possess a
+clear understanding of the natural processes we propose
+to use, let us refer to any text-book on physics,
+and review briefly some of the natural laws relating
+to motion and force which apply to the problem of
+flight:</p>
+
+<blockquote>
+
+<p>(<i>a</i>) Force is that power which changes or
+tends to change the position of a body, whether
+it is in motion or at rest.</p>
+
+<p>(<i>b</i>) A given force will produce the same effect,
+whether the body on which it acts is acted
+upon by that force alone, or by other forces
+at the same time.</p>
+
+<p>(<i>c</i>) A force may be represented graphically
+<span class="pagenum" id="Page_45">45</span>
+<span class="pagenum" id="Page_46">46</span>
+by a straight line&mdash;the point at which the force
+is applied being the beginning of the line; the
+direction of the force being expressed by the direction
+of the line; and the magnitude of the
+force being expressed by the length of the line.</p>
+
+<p>(<i>d</i>) Two or more forces acting upon a body
+are called component forces, and the single
+force which would produce the same effect is
+called the resultant.</p>
+
+<p>(<i>e</i>) When two component forces act in different
+directions the resultant may be found by
+applying the principle of the parallelogram of
+forces&mdash;the lines (<i>c</i>) representing the components
+being made adjacent sides of a parallelogram,
+and the diagonal drawn from the included
+angle representing the resultant in
+direction and magnitude.</p>
+
+<p>(<i>f</i>) Conversely, a resultant motion may be
+resolved into its components by constructing a
+parallelogram upon it as the diagonal, either
+one of the components being known.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_045.jpg" alt="" />
+<p class="caption">The Deutsch de la Muerthe dirigible balloon <i>Ville-de-Paris</i>; an example of the “cigar-shaped” gas envelope.</p></div>
+
+<p>Taking up again the illustration of the kite flying
+in a calm, let us construct a few diagrams to show
+graphically the forces at work upon the kite. Let
+<span class="pagenum" id="Page_47">47</span>
+the heavy line AB represent the centre line of the
+kite from top to bottom, and C the point where the
+string is attached, at which point we may suppose all
+the forces concentrate their action upon the plane of
+the kite. Obviously, as the flyer of the kite is running
+in a horizontal direction, the line indicating the
+pull of the string is to be drawn horizontal. Let it
+be expressed by CD. The action of the air pressure
+being at right angles to the plane of the kite, we
+draw the line CE representing that force. But as
+this is a <i>pressing</i> force at the point C, we may express
+it as a <i>pulling</i> force on the other side of the
+kite by the line CF, equal to CE and in the opposite
+direction. Another force acting on the kite is its
+weight&mdash;the attraction of gravity acting directly
+downward, shown by CG. We have given, therefore,
+the three forces, CD, CF, and CG. We now wish to
+find the value of the pull on the kite-string, CD, in
+two other forces, one of which shall be a lifting force,
+acting directly upward, and the other a propelling
+force, acting in the direction in which we desire the
+kite to travel&mdash;supposing it to represent an aeroplane
+for the moment.</p>
+
+<p>We first construct a parallelogram on CF and CG,
+and draw the diagonal CH, which represents the resultant
+<span class="pagenum" id="Page_48">48</span>
+<span class="pagenum" id="Page_49">49</span>
+of those two forces. We have then the two
+forces CD and CH acting on the point C. To avoid
+obscuring the diagram with too many lines, we draw
+a second figure, showing just these two forces acting
+on the point C. Upon these we construct a new parallelogram,
+and draw the diagonal CI, expressing
+their resultant. Again drawing a new diagram,
+showing this single force CI acting upon the point
+C, we resolve that force into two components&mdash;one,
+CJ, vertically upward, representing the lift; the
+other, CK, horizontal, representing the travelling
+power. If the lines expressing these forces in the
+diagrams had been accurately drawn to scale, the
+measurement of the two components last found
+would give definite results in pounds; but the weight
+of a kite is too small to be thus diagrammed, and
+only the principle was to be illustrated, to be used
+later in the discussion of the aeroplane.</p>
+
+<div class="figcenter">
+<img src="images/i_048.jpg" alt="" />
+</div>
+
+<p>Nor is the problem as simple as the illustration
+of the kite suggests, for the air is compressible, and
+is moreover set in motion in the form of a current
+by a body passing through it at anything like the ordinary
+speed of an aeroplane. This has caused the
+curving of the planes (from front to rear) of the
+flying machine, in contrast with the flat plane of the
+<span class="pagenum" id="Page_50">50</span>
+kite. The reasoning is along this line: Suppose the
+main plane of an aeroplane six feet in depth (from
+front to rear) to be passing rapidly through the air,
+inclined upward at a slight angle. By the time two
+feet of this depth has passed a certain point, the air
+at that point will have received a downward impulse
+or compression which will tend to make it flow in the
+direction of the angle of the plane. The second and
+third divisions in the depth, each of two feet, will
+therefore be moving with a partial vacuum beneath,
+the air having been drawn away by the first segment.
+At the same time, the pressure of the air
+from above remains the same, and the result is that
+only the front edge of the plane is supported, while
+two-thirds of its depth is pushed down. This condition
+not only reduces the supporting surface to
+that of a plane two feet in depth, but, what is much
+worse, releases a tipping force which tends to throw
+the plane over backward.</p>
+
+<p>In order that the second section of the plane may
+bear upon the air beneath it with a pressure equal
+to that of the first, it must be inclined downward at
+double the angle (with the horizon) of the first section;
+this will in turn give to the air beneath it a
+new direction. The third section of the plane must
+<span class="pagenum" id="Page_51">51</span>
+then be set at a still deeper angle to give it support.
+Connecting these several directions with a smoothly
+flowing line without angles, we get the curved line
+of section to which the main planes of aeroplanes are
+bent.</p>
+
+<p>With these principles in mind, it is in order to
+apply them to the understanding of how an aeroplane
+flies. Wilbur Wright, when asked what kept his
+machine up in the air&mdash;why it did not fall to the
+ground&mdash;replied: “It stays up because it doesn’t
+have time to fall.” Just what he meant by this may
+be illustrated by referring to the common sport of
+“skipping stones” upon the surface of still water.
+A flat stone is selected, and it is thrown at a high
+speed so that the flat surface touches the water. It
+continues “skipping,” again and again, until its
+speed is so reduced that the water where it touches
+last has time to get out of the way, and the weight
+of the stone carries it to the bottom. On the same
+principle, a person skating swiftly across very thin
+ice will pass safely over if he goes so fast that the
+ice hasn’t time to break and give way beneath his
+weight. This explains why an aeroplane must move
+swiftly to stay up in the air, which has much less
+density than either water or ice. The minimum
+<span class="pagenum" id="Page_52">52</span>
+speed at which an aeroplane can remain in the air
+depends largely upon its weight. The heavier it is,
+the faster it must go&mdash;just as a large man must
+move faster over thin ice than a small boy. At
+some aviation contests, prizes have been awarded for
+the slowest speed made by an aeroplane. So far, the
+slowest on record is that of 21.29 miles an hour,
+made by Captain Dickson at the Lanark meet, Scotland,
+in August, 1910. As the usual rate of speed
+is about 46 miles an hour, that is slow for an aeroplane;
+and as Dickson’s machine is much heavier
+than some others&mdash;the Curtiss machine, for instance&mdash;it
+is remarkably slow for that type of aeroplane.</p>
+
+<p>Just what is to be gained by offering a prize for
+slowest speed is difficult to conjecture. It is like
+offering a prize to a crowd of boys for the one who
+can skate slowest over thin ice. The minimum speed
+is the most dangerous with the aeroplane as with the
+skater. Other things being equal, the highest speed
+is the safest for an aeroplane. Even when his engine
+stops in mid-air, the aviator is compelled to keep up
+speed sufficient to prevent a fall by gliding swiftly
+downward until the very moment of landing.</p>
+
+<p>The air surface necessary to float a plane is spread
+out in one area in the monoplane, and divided into
+<span class="pagenum" id="Page_53">53</span>
+two areas, one above the other and 6 to 9 feet apart,
+in the biplane; if closer than this, the disturbance
+of the air by the passage of one plane affects the supporting
+power of the other. It has been suggested
+that better results in the line of carrying power
+would be secured by so placing the upper plane that
+its front edge is a little back of the rear edge of the
+lower plane, in order that it may enter air that is
+wholly free from any currents produced by the rushing
+of the lower plane.</p>
+
+<p>As yet, there is a difference of opinion among the
+principal aeroplane builders as to where the propeller
+should be placed. All of the monoplanes have
+it in front of the main plane. Most of the biplanes
+have it behind the main plane; some have it between
+the two planes. If it is in front, it works in undisturbed
+air, but throws its wake upon the plane. If
+it is in the rear, the air is full of currents caused
+by the passage of the planes, but the planes have
+smooth air to glide into. As both types of machine
+are eminently successful, the question may not be so
+important as it seems to the disputants.</p>
+
+<p>The exact form of curve for the planes has not
+been decided upon. Experience has proven that of
+two aeroplanes having the same surface and run at
+<span class="pagenum" id="Page_54">54</span>
+the same speed, one may be able to lift twice as much
+as the other because of the better curvature of its
+planes. The action of the air when surfaces are
+driven through it is not fully understood. Indeed,
+the form of plane shown in the accompanying figure
+is called the aeroplane paradox. If driven in either
+direction it leaves the air with a <i>downward</i> trend,
+and therefore exerts a proportional lifting power.
+If half of the plane is taken away, the other half
+is pressed downward. All of the lifting effect is in
+the curving of the top side. It seems desirable, therefore,
+that such essential factors should be thoroughly
+worked out, understood, and applied.</p>
+
+<div class="figcenter">
+<img src="images/i_054.jpg" alt="" />
+<p class="caption">Section of the “paradox” aeroplane.
+<span class="pagenum" id="Page_55">55</span></p></div>
+
+<hr class="chap" />
+
+<h2 id="Chapter_IV">Chapter IV.<br />
+
+FLYING MACHINES.</h2>
+
+<blockquote>
+
+<p>Mythological&mdash;Leonardo da Vinci&mdash;Veranzio&mdash;John Wilkins&mdash;Besnier&mdash;Marquis
+de Bacqueville&mdash;Paucton&mdash;Desforges&mdash;Meerwein&mdash;Stentzel&mdash;Henson&mdash;Von
+Drieberg&mdash;Wenham&mdash;Horatio
+Phillips&mdash;Sir Hiram Maxim&mdash;Lilienthal&mdash;Langley&mdash;Ader&mdash;Pilcher&mdash;Octave
+Chanute&mdash;Herring&mdash;Hargrave&mdash;The
+Wright brothers&mdash;Archdeacon&mdash;Santos-Dumont&mdash;Voisin&mdash;Bleriot.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> term Flying Machines is applied to all
+forms of aircraft which are heavier than air,
+and which lift and sustain themselves in the air by
+mechanical means. In this respect they are distinguished
+from balloons, which are lifted and sustained
+in the air by the lighter-than-air gas which
+they contain.</p>
+
+<p>From the earliest times the desire to fly in the air
+has been one of the strong ambitions of the human
+race. Even the prehistoric mythology of the ancient
+Greeks reflected the idea in the story of Icarus, who
+flew so near to the sun that the heat melted the wax
+which fastened his wings to his body, and he fell
+into the sea.
+<span class="pagenum" id="Page_56">56</span></p>
+
+<p>Perhaps the first historical record in the line of
+mechanical flight worthy of attention exists in the
+remarkable sketches and plans for a flying mechanism
+left by Leonardo da Vinci at his death in 1519.
+He had followed the model of the flying bird as closely
+as possible, although when the wings were outspread
+they had an outline more like those of the bat.
+While extremely ingenious in the arrangement of the
+levers, the power necessary to move them fast enough
+to lift the weight of a man was far beyond the muscular
+strength of any human being.</p>
+
+<p>It was a century later, in 1617, that Veranzio, a
+Venetian, proved his faith in his inventive ability
+by leaping from a tower in Venice with a crude,
+parachute-like contrivance. He alighted without injury.</p>
+
+<p>In 1684, an Englishman, John Wilkins, then
+bishop of Chester, built a machine for flying in
+which he installed a steam-engine. No record exists
+of its performance.</p>
+
+<p>In 1678, a French locksmith by the name of Besnier
+devised what seems now a very crude apparatus
+for making descending flights, or glides, from elevated
+points. It was, however, at that date considered
+important enough to be described in the <i>Journal</i>
+<span class="pagenum" id="Page_57">57</span>
+<i>of the Savants</i>. It was a wholly unscientific combination
+of the “dog-paddle” motion in swimming,
+with wing areas which collapsed on the upward motion
+and spread out on the downward thrust. If
+it was ever put to a test it must have failed completely.</p>
+
+<p>In 1742, the Marquis de Bacqueville constructed
+an apparatus which some consider to have been
+based on Besnier’s idea&mdash;which seems rather doubtful.
+He fastened the surfaces of his aeroplane directly
+to his arms and legs, and succeeded in making
+a long glide from the window of his mansion
+across the garden of the Tuileries, alighting upon
+a washerwoman’s bench in the Seine without injury.</p>
+
+<p>Paucton, the mathematician, is credited with the
+suggestion of a flying machine with two screw propellers,
+which he called “pterophores”&mdash;a horizontal
+one to raise the machine into the air, and an upright
+one to propel it. These were to be driven by hand.
+With such hopelessly inadequate power it is not surprising
+that nothing came of it, yet the plan was a
+foreshadowing of the machine which has in these
+days achieved success.</p>
+
+<p>The Abbé Desforges gained a place in the annals
+<span class="pagenum" id="Page_58">58</span>
+of aeronautics by inventing a flying machine of
+which only the name “Orthoptere” remains.</p>
+
+<div class="figcenter">
+<img src="images/i_058.jpg" alt="" />
+<p class="caption">Meerwein’s Flying Machine. <i>A</i>, shows the position of the man in the wings,
+their comparative size, and the operating levers; <i>B</i>, position when in flight.</p></div>
+
+<p>About 1780, Karl Friedrich Meerwein, an architect,
+and the Inspector of Public Buildings for
+Baden, Germany, made many scientific calculations
+and experiments on the size of wing surface needed
+to support a man in the air. He used the wild duck
+as a standard, and figured that a surface of 126
+square feet would sustain a man in the air. This
+agrees with the later calculations of such experimenters
+as Lilienthal and Langley. Other of Meerwein’s
+<span class="pagenum" id="Page_59">59</span>
+conclusions are decidedly ludicrous. He held
+that the build of a man favors a horizontal position
+in flying, as his nostrils open in a direction which
+would be away from the wind, and so respiration
+would not be interfered with! Some of his reasoning
+is unaccountably astray; as, for instance, his argument
+that because the man hangs in the wings the
+weight of the latter need not be considered. It is
+almost needless to say that his practical trials were
+a total failure.</p>
+
+<div class="figcenter">
+<img src="images/i_059.jpg" alt="" />
+<p class="caption">Plan of Degen’s apparatus.</p></div>
+
+<p>The next prominent step forward toward mechanical
+flight was made by the Australian watchmaker
+Degen, who balanced his wing surfaces with
+a small gas balloon. His first efforts to fly not being
+successful, he abandoned his invention and took to
+ballooning.</p>
+
+<p>Stentzel, an engineer of Hamburg, came next with
+<span class="pagenum" id="Page_60">60</span>
+a machine in the form of a gigantic butterfly. From
+tip to tip of its wings it measured 20 feet, and their
+depth fore and aft was 5½ feet. The ribs of the
+wings were of steel and the web of silk, and they
+were slightly concave on the lower side. The rudder-tail
+was of two intersecting planes, one vertical
+and the other horizontal. It was operated by a carbonic-acid
+motor, and made 84 flaps of the wings
+per minute. The rush of air it produced was so
+<span class="pagenum" id="Page_61">61</span>
+great that any one standing near it would be almost
+swept off his feet. It did not reach a stage beyond
+the model, for it was able to lift only 75 lbs.</p>
+
+<div class="figcenter">
+<img src="images/i_060.jpg" alt="" />
+<p class="caption">Stentzel’s machine.</p></div>
+
+<p>In 1843, the English inventor Henson built what
+is admitted to be the first aeroplane driven by motive
+power. It was 100 feet in breadth (spread) and 30
+feet long, and covered with silk. The front edge was
+turned slightly upward. It had a rudder shaped like
+the tail of a bird. It was driven by two propellers
+run by a 20-horse-power engine. Henson succeeded
+only in flying on a down grade, doubtless because of
+the upward bend of the front of his plane. Later
+investigations have proven that the upper surface of
+the aeroplane must be convex to gain the lifting effect.
+This is one of the paradoxes of flying planes
+which no one has been able to explain.</p>
+
+<p>In 1845, Von Drieberg, in Germany, revived the
+sixteenth-century ideas of flying, with the quite original
+argument that since the legs of man were better
+developed muscularly than his arms, flying should be
+done with the legs. He built a machine on this plan,
+but no successful flights are recorded.</p>
+
+<p>In 1868, an experimenter by the name of Wenham
+added to the increasing sum of aeronautical
+knowledge by discovering that the lifting power of
+<span class="pagenum" id="Page_62">62</span>
+a large supporting surface may be as well secured
+by a number of small surfaces placed one above another.
+Following up these experiments, he built a
+flying machine with a series of six supporting planes
+made of linen fabric. As he depended upon muscular
+effort to work his propellers, he did not succeed
+in flying, but he gained information which has been
+valuable to later inventors.</p>
+
+<div class="figcenter">
+<img src="images/i_062a.jpg" alt="" />
+<p class="caption">Von Drieberg’s machine; view from above.</p></div>
+
+<div class="figcenter">
+<img src="images/i_062b.jpg" alt="" />
+<blockquote>
+
+<p>Wenham’s arrangement of many narrow surfaces in six tiers, or decks. <i>a</i>, <i>a</i>,
+rigid framework; <i>b</i>, <i>b</i>, levers working flapping wings; <i>e</i>, <i>e</i>, braces. The
+operator is lying prone.</p></blockquote>
+</div>
+
+<p>The history of flying machines cannot be written
+<span class="pagenum" id="Page_63">63</span>
+without deferential mention of Horatio Phillips of
+England. The machine that he made in 1862 resembled
+a large Venetian blind, 9 feet high and over
+21 feet long. It was mounted on a carriage which
+travelled on a circular track 600 feet long, and it was
+driven by a small steam engine turning a propeller.
+It lifted unusually heavy loads, although not large
+enough to carry a man. It seems to open the way
+for experiments with an entirely new arrangement
+of sustaining surfaces&mdash;one that has never since
+been investigated. Phillips’s records cover a series
+of most valuable experiments. Perhaps his most important
+work was in the determination of the most
+<span class="pagenum" id="Page_64">64</span>
+advantageous form for the surfaces of aeroplanes,
+and his researches into the correct proportion of motive
+power to the area of such surfaces. Much of
+his results have not yet been put to practical use by
+designers of flying machines.</p>
+
+<div class="figcenter">
+<img src="images/i_063.jpg" alt="" />
+<p class="caption">Phillips’s Flying Machine&mdash;built of narrow slats like a Venetian blind.</p></div>
+
+<p>The year 1888 was marked by the construction by
+Sir Hiram Maxim of his great aeroplane which
+weighed three and one-half tons, and is said to have
+cost over $100,000. The area of the planes was
+3,875 square feet, and it was propelled by a steam
+engine in which the fuel used was vaporized naphtha
+in a burner having 7,500 jets, under a boiler of
+small copper water tubes. With a steam pressure of
+320 lbs. per square inch, the two compound engines
+each developed 180 horse-power, and each turned a
+two-bladed propeller 17½ feet in diameter. The machine
+was used only in making tests, being prevented
+from rising in the air by a restraining track. The
+thrust developed on trial was 2,164 lbs., and the lifting
+power was shown to have been in excess of 10,000 lbs.
+The restraining track was torn to pieces, and
+the machine injured by the fragments. The dynamometer
+record proved that a dead weight of 4½
+tons, in addition to the weight of the machine and
+the crew of 4 men, could have been lifted. The
+<span class="pagenum" id="Page_65">65</span>
+stability, speed, and steering control were not tested.
+Sir Hiram Maxim made unnumbered experiments
+with models, gaining information which has been invaluable
+in the development of the aeroplane.</p>
+
+<div class="figcenter">
+<img src="images/i_065.jpg" alt="" />
+<p class="caption">View of a part of Maxim’s aeroplane, showing one of the immense propellers.
+At the top is a part of the upper plane.</p></div>
+
+<p>The experiments of Otto Lilienthal in gliding
+<span class="pagenum" id="Page_66">66</span>
+with a winged structure were being conducted at this
+period. He held that success in flying must be
+founded upon proficiency in the art of balancing the
+apparatus in the air. He made innumerable glides
+from heights which he continually increased until he
+was travelling distances of nearly one-fourth of a
+mile from an elevation of 100 feet. He had reached
+the point where he was ready to install motive power
+to drive his glider when he met with a fatal accident.
+Besides the inspiration of his daring personal experiments
+in the air, he left a most valuable series
+<span class="pagenum" id="Page_67">67</span>
+of records and calculations, which have been of the
+greatest aid to other inventors in the line of artificial
+flight.</p>
+
+<div class="figcenter">
+<img src="images/i_066.jpg" alt="" />
+<p class="caption">Lilienthal in his biplane glider.</p></div>
+
+<p>In 1896, Professor Langley, director of the Smithsonian
+Institution at Washington, made a test of a
+model flying machine which was the result of years
+of experimenting. It had a span of 15 feet, and a
+length of 8½ feet without the extended rudder.
+There were 4 sails or planes, 2 on each side, 30
+inches in width (fore-and-aft measurement). Two
+propellers revolving in opposite directions were driven
+by a steam engine. The diameter of the propellers
+was 3 feet, and the steam pressure 150 lbs.
+per square inch. The weight of the machine was
+28 lbs. It is said to have made a distance of 1
+mile in 1 minute 45 seconds. As Professor Langley’s
+experiments were conducted in strict secrecy,
+no authoritative figures are in existence. Later a
+larger machine was built, which was intended to
+carry a man. It had a spread of 46 feet, and was
+35 feet in length. It was four years in building,
+and cost about $50,000. In the first attempt to
+launch it, from the roof of a house-boat, it plunged
+into the Potomac River. The explanation given was
+that the launching apparatus was defective. This
+<span class="pagenum" id="Page_68">68</span>
+was remedied, and a second trial made, but the same
+result followed. It was never tried again. This
+machine was really a double, or tandem, monoplane.
+The framework was built of steel tubing almost as
+thin as writing paper. Every rib and pulley was
+hollowed out to reduce the weight. The total weight
+of the engine and machine was 800 lbs., and the
+supporting surface of the wings was 1,040 square
+feet. The aeroplanes now in use average from 2 to
+4 lbs. weight to the square foot of sustaining surface.</p>
+
+<p>About the same time the French electrician Ader,
+after years of experimenting, with the financial aid
+of the French Government, made some secret trials
+of his machine, which had taken five years to build.
+It had two bat-like wings spreading 54 feet, and was
+propelled by two screws driven by a 4-cylinder
+steam engine which has been described as a marvel
+of lightness. The inventor claimed that he was able
+to rise to a height of 60 feet, and that he made flights
+of several hundred yards. The official tests, however,
+were unsatisfactory, and nothing further was
+done by either the inventor or the government to continue
+the experiments. The report was that in every
+trial the machines had been wrecked.</p>
+
+<p>The experiments of Lilienthal had excited an interest
+<span class="pagenum" id="Page_69">69</span>
+in his ideas which his untimely death did not
+abate. Among others, a young English marine engineer,
+Percy S. Pilcher, took up the problem of
+gliding flight, and by the device of using the power
+exerted by running boys (with a five-fold multiplying
+gear) he secured speed enough to float his glider horizontally
+in the air for some distance. He then built
+an engine which he purposed to install as motive
+power, but before this was done he was killed by a
+fall from his machine while in the air.</p>
+
+<div class="figcenter">
+<img src="images/i_069.jpg" alt="" />
+<p class="caption">Plan of Chanute’s movable-wing glider.</p></div>
+
+<p>Before the death of Lilienthal his efforts had attracted
+the attention of Octave Chanute, a distinguished
+<span class="pagenum" id="Page_70">70</span>
+civil engineer of Chicago, who, believing
+that the real problem of the glider was the maintenance
+of equilibrium in the air, instituted a series
+of experiments along that line. Lilienthal had preserved
+his equilibrium by moving his body about as
+he hung suspended under the wings of his machine.
+Chanute proposed to accomplish the same end by
+moving the wings automatically. His attempts were
+partially successful. He constructed several types of
+gliders, one of these with two decks exactly in the
+form of the present biplane. Others had three or
+more decks. Upward of seven hundred glides were
+made with Chanute’s machines by himself and assistants,
+without a single accident. It is of interest
+to note that a month before the fatal accident to
+<span class="pagenum" id="Page_71">71</span>
+Lilienthal, Chanute had condemned that form of
+glider as unsafe.</p>
+
+<div class="figcenter">
+<img src="images/i_070.jpg" alt="" />
+<p class="caption">Chanute’s two-deck glider.</p></div>
+
+<p>In 1897, A. M. Herring, who had been one of
+the foremost assistants of Octave Chanute, built a
+double-deck (biplane) machine and equipped it with
+a gasoline motor between the planes. The engine
+failed to produce sufficient power, and an engine
+operated by compressed air was tried, but without
+the desired success.</p>
+
+<p>In 1898, Lawrence Hargrave of Sydney, New
+South Wales, came into prominence as the inventor
+of the cellular or box kite. Following the researches
+of Chanute, he made a series of experiments upon
+the path of air currents under variously curved
+surfaces, and constructed some kites which, under
+certain conditions, would advance against a wind believed
+to be absolutely horizontal. From these results
+Hargrave was led to assert that “soaring
+sails” might be used to furnish propulsion, not only
+for flying machines, but also for ships on the ocean
+sailing against the wind. The principles involved
+remain in obscurity.</p>
+
+<p>During the years 1900 to 1903, the brothers
+Wright, of Dayton, Ohio, had been experimenting
+with gliders among the sand dunes of Kitty Hawk,
+<span class="pagenum" id="Page_72">72</span>
+North Carolina, a small hamlet on the Atlantic
+Coast. They had gone there because the Government
+meteorological department had informed them that at
+Kitty Hawk the winds blew more steadily than at
+any other locality in the United States. Toward the
+end of the summer of 1903, they decided that the
+time was ripe for the installation of motive power,
+and on December 17, 1903, they made their first
+four flights under power, the longest being 853 feet
+in 59 seconds&mdash;against a wind blowing nearly 20
+miles an hour, and from a starting point on level
+ground.</p>
+
+<div class="figcenter">
+<img src="images/i_072.jpg" alt="" />
+<p class="caption">Wilbur Wright gliding at Kitty Hawk, N. C., in 1903.</p></div>
+
+<p>During 1904 over one hundred flights were made,
+<span class="pagenum" id="Page_73">73</span>
+and changes in construction necessary to sail in circles
+were devised. In 1905, the Wrights kept on
+secretly with their practice and development of their
+machine, first one and then the other making the
+flights until both were equally proficient. In the
+latter part of September and early part of October,
+1905, occurred a series of flights which the Wrights
+allowed to become known to the public. At a meeting
+of the Aeronautical Society of Great Britain,
+held in London on December 15, 1905, a letter from
+Orville Wright to one of the members was read.
+It was dated November 17, 1905, and an excerpt
+from it is as follows:</p>
+
+<p>“During the month of September we gradually
+improved in our practice, and on the 26th made a
+flight of a little over 11 miles. On the 30th we increased
+this to 12⅕th miles; on October 3, to 15⅓
+miles; on October 4, to 20¾ miles, and on October 5,
+to 24¼ miles. All these flights were made at about
+38 miles an hour, the flight of October 5 occupying
+30 minutes 3 seconds. Landings were caused by the
+exhaustion of the supply of fuel in the flights of
+September 26 and 30, and October 8, and in those
+of October 3 and 4 by the heating of the bearings
+in the transmission, of which the oil cups had been
+<span class="pagenum" id="Page_74">74</span>
+omitted. But before the flight on October 5, oil cups
+had been fitted to all the bearings, and the small
+gasoline can had been replaced with one that carried
+enough fuel for an hour’s flight. Unfortunately, we
+neglected to refill the reservoir just before starting,
+and as a result the flight was limited to 38 minutes....</p>
+
+<div class="figcenter">
+<img src="images/i_074.jpg" alt="" />
+<p class="caption">A Wright machine in flight.</p></div>
+
+<p>“The machine passed through all of these flights
+without the slightest damage. In each of these
+<span class="pagenum" id="Page_75">75</span>
+flights we returned frequently to the starting point,
+passing high over the heads of the spectators.”</p>
+
+<p>These statements were received with incredulity
+in many parts of Europe, the more so as the
+Wrights refused to permit an examination of their
+machine, fearing that the details of construction
+might become known before their patents were
+secured.</p>
+
+<div class="figcenter">
+<img src="images/i_075.jpg" alt="" />
+<p class="caption">The Archdeacon machine on the Seine.</p></div>
+
+<p>During the summer of 1905, Captain Ferber and
+Ernest Archdeacon of Paris had made experiments
+with gliders. One of the Archdeacon machines
+was towed by an automobile, having a bag of
+sand to occupy the place of the pilot. It rose
+satisfactorily in the air, but the tail became disarranged,
+<span class="pagenum" id="Page_76">76</span>
+and it fell and was damaged. It was rebuilt
+and tried upon the waters of the Seine, being
+towed by a fast motor-boat at a speed of 25 miles
+an hour. The machine rose about 50 feet into the
+air and sailed for about 500 feet.</p>
+
+<p>Archdeacon gathered a company of young men
+about him who speedily became imbued with his enthusiasm.
+Among them were Gabriel Voisin, Louis
+Bleriot, and Leon Delagrange. The two former,
+working together, built and flew several gliders, and
+when Santos-Dumont made his historic flight of 720
+feet with his multiple-cell machine on November 13,
+1906 (the first flight made in Europe), they were
+spurred to new endeavors.</p>
+
+<p>Within a few months Voisin had finished his
+first biplane, and Delagrange made his initial
+flight with it&mdash;a mere hop of 30 feet&mdash;on March
+16, 1907.</p>
+
+<p>Bleriot, however, had his own ideas, and on August
+6, 1907, he flew for 470 feet in a monoplane
+machine of the tandem type. He succeeded in steering
+his machine in a curved course, a feat which had
+not previously been accomplished in Europe.</p>
+
+<p>In October of the same year, Henri Farman, then
+a well-known automobile driver, flew the second
+<span class="pagenum" id="Page_77">77</span>
+Voisin biplane in a half circle of 253 feet&mdash;a notable
+achievement at that date.</p>
+
+<p>But Santos-Dumont had been pushing forward
+several different types of machines, and in November
+he flew first a biplane 500 feet, and a few days later
+a monoplane 400 feet.</p>
+
+<p>At this point in our story the past seems to give
+place to the present. The period of early development
+was over, and the year 1908 saw the first of
+those remarkable exploits which are recorded in the
+chapter near the end of this work entitled, “Chronicle
+of Aviation Achievements.”</p>
+
+<p>It is interesting to note that the machines then
+brought out are those of to-day. Practically, it may
+be said that there has been no material change from
+the original types. More powerful engines have
+been put in them, and the frames strengthened in
+proportion, but the Voisin, the Bleriot, and the
+Wright types remain as they were at first. Other
+and later forms are largely modifications and combinations
+of their peculiar features.
+<span class="pagenum" id="Page_78">78</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_V">Chapter V.<br />
+
+FLYING MACHINES: THE BIPLANE.</h2>
+
+<blockquote>
+
+<p>Successful types of aeroplanes&mdash;Distinguishing features&mdash;The
+Wright biplane&mdash;Construction&mdash;New type&mdash;Five-passenger
+machine&mdash;The Voisin biplane&mdash;New racing type&mdash;The Curtiss
+biplane&mdash;The Cody biplane&mdash;The Sommer biplane&mdash;The
+Baldwin biplane&mdash;New stabilizing plane&mdash;The Baddeck
+No. 2&mdash;Self-sustaining radiator&mdash;The Herring biplane&mdash;Stabilizing
+fins.</p></blockquote>
+
+<p class="drop"><span class="uppercase">In</span> the many contests for prizes and records, two
+types of flying machines have won distinctive
+places for themselves&mdash;the biplane and the monoplane.
+The appearance of other forms has been
+sporadic, and they have speedily disappeared without
+accomplishing anything which had not been better
+done by the two classes named.</p>
+
+<p>This fact, however, should not be construed as
+proving the futility of all other forms, nor that the
+ideal flying machine must be of one of these two
+prominent types. It is to be remembered that record-making
+and record-breaking is the most serious
+business in which any machines have so far been
+<span class="pagenum" id="Page_79">79</span>
+<span class="pagenum" id="Page_80">80</span>
+engaged; and this, surely, is not the field of usefulness
+to humanity which the ships of the air may be
+expected ultimately to occupy. It may yet be proved
+that, successful as these machines have been in what
+they have attempted, they are but transition forms
+leading up to the perfect airship of the future.</p>
+
+<div class="figcenter">
+<img src="images/i_079.jpg" alt="" />
+<p class="caption">The Wright biplane in flight.</p></div>
+
+<p>The distinguishing feature of the biplane is not
+alone that it has two main planes, but that they are
+placed one above the other. The double (or tandem)
+monoplane also has two main planes, but they are on
+the same level, one in the rear of the other.</p>
+
+<p>A review of the notable biplanes of the day must
+begin with the Wright machine, which was not only
+the first with which flights were made, but also the
+inspiration and perhaps the pattern of the whole
+succeeding fleet.</p>
+
+<h3>THE WRIGHT BIPLANE.</h3>
+
+<p>The Wright biplane is a structure composed of
+two main surfaces, each 40 feet long and 6 feet 6
+inches wide, set one above the other, parallel, and
+6 feet apart. The planes are held rigidly at this distance
+by struts of wood, and the whole structure is
+trussed with diagonal wire ties. It is claimed by
+the Wrights that these dimensions have been proven
+<span class="pagenum" id="Page_81">81</span>
+<span class="pagenum" id="Page_82">82</span>
+by their experiments to give the maximum lift with
+the minimum weight.</p>
+
+<div class="figcenter">
+<img src="images/i_081.jpg" alt="" />
+<blockquote>
+
+<p>Diagram showing the construction of the Wright biplane. The lever <i>R</i> is connected by the bar <i>A</i> with the rudder gearing <i>C</i>,
+and is pivoted at the bottom on a rolling shaft <i>B</i>, through which the warping wires <i>W</i><sup>1</sup>, <i>W</i><sup>2</sup> are operated. The semicircular
+planes <i>F</i> aid in stabilizing the elevator system.</p></blockquote>
+</div>
+
+<p>The combination of planes is mounted on two
+rigid skids, or runners (similar to the runners of a
+sleigh), which are extended forward and upward to
+form a support for a pair of smaller planes in parallel,
+used as the elevator (for directing the course
+of the aeroplane upward or downward). It has been
+claimed by the Wrights that a rigid skid under-structure
+takes up the shock of landing, and checks
+the momentum at that moment, better than any other
+device. But it necessitated a separate starting apparatus,
+and while the starting impulse thus received
+enabled the Wrights to use an engine of less power
+(to keep the machine going when once started), and
+therefore of less dead weight, it proved a handicap
+to their machines in contests where they were met by
+competing machines which started directly with their
+own power. A later model of the Wright biplane
+is provided with a wheeled running gear, and an
+engine of sufficient power to raise it in the air after
+a short run on the wheels.</p>
+
+<p>Two propellers are used, run by one motor. They
+are built of wood, are of the two-bladed type, and
+are of comparatively large diameter&mdash;8 feet. They
+<span class="pagenum" id="Page_83">83</span>
+revolve in opposite directions at a speed of 450 revolutions
+per minute, being geared down by chain
+drive from the engine speed of 1,500 revolutions per
+minute.</p>
+
+<p>The large elevator planes in front have been a distinctive
+feature of the Wright machine. They have
+a combined area of 80 square feet, adding that much
+more lifting surface to the planes in ascending, for
+then the under side of their surfaces is exposed to
+the wind. If the same surfaces were in the rear
+of the main planes their top sides would have to be
+turned to the wind when ascending, and a depressing
+instead of a lifting effect would result.</p>
+
+<p>To the rear of the main planes is a rudder composed
+of two parallel vertical surfaces for steering
+to right or left.</p>
+
+<p>The feature essential to the Wright biplane, upon
+which the letters patent were granted, is the flexible
+construction of the tips of the main planes, in virtue
+of which they may be warped up or down to restore
+disturbed equilibrium, or when a turn is to be made.
+This warping of the planes changes the angle of incidence
+for the part of the plane which is bent.
+(The angle of incidence is that which the plane
+makes with the line in which it is moving. The
+<span class="pagenum" id="Page_84">84</span>
+bending downward of the rear edge would enlarge the
+angle of incidence, in that way increasing the compression
+of the air beneath, and lifting that end of
+the plane.) The wing-warping controls are actuated
+by the lever at the right hand of the pilot, which
+also turns the rudder at the rear&mdash;that which steers
+the machine to right or to left. The lever at the left
+hand of the pilot moves the elevating planes at the
+front of the machine.</p>
+
+<div class="figcenter">
+<img src="images/i_084.jpg" alt="" />
+<blockquote>
+
+<p>Sketch showing relative positions of planes and of the operator in the Wright
+machine: <i>A</i>, <i>A</i>, the main planes; <i>B</i>, <i>B</i>, the elevator planes. The motor
+is placed beside the operator.</p></blockquote>
+</div>
+
+<p>The motor has 4 cylinders, and develops 25 to
+30 horse-power, giving the machine a speed of 39
+miles per hour.</p>
+
+<p>A newer model of the Wright machine is built
+without the large elevating planes in front, a single
+elevating plane being placed just back of the rear
+rudder. This arrangement cuts out the former lifting
+effect described above, and substitutes the depressing
+<span class="pagenum" id="Page_85">85</span>
+<span class="pagenum" id="Page_86">86</span>
+effect due to exposing the top of a surface
+to the wind.</p>
+
+<div class="figcenter">
+<img src="images/i_085.jpg" alt="" />
+<p class="small"><i>Courtesy of N. Y. Times.</i></p>
+
+<p class="caption">The new model Wright biplane&mdash;without forward elevator.</p></div>
+
+<p>The smallest of the Wright machines, popularly
+called the “Baby Wright,” is built upon this plan,
+and has proven to be the fastest of all the Wright
+series.</p>
+
+<h3>THE VOISIN BIPLANE.</h3>
+
+<p>While the Wrights were busily engaged in developing
+their biplane in America, a group of enthusiasts
+in France were experimenting with gliders of
+various types, towing them with high speed automobiles
+along the roads, or with swift motor-boats
+upon the Seine. As an outcome of these experiments,
+in which they bore an active part, the Voisin
+brothers began building the biplanes which have
+made them famous.</p>
+
+<p>As compared with the Wright machine, the Voisin
+aeroplane is of much heavier construction. It
+weighs 1,100 pounds. The main planes have a lateral
+spread of 37 feet 9 inches, and a breadth of 7
+feet, giving a combined area of 540 square feet, the
+same as that of the Wright machine. The lower
+main plane is divided at the centre to allow the introduction
+of a trussed girder framework which carries
+<span class="pagenum" id="Page_87">87</span>
+the motor and propeller, the pilot’s seat, the
+controlling mechanism, and the running gear below;
+and it is extended forward to support the elevator.
+This is much lower than in the Wright machine,
+being nearly on the level of the lower plane. It is
+a single surface, divided at the centre, half being
+placed on each side of the girder. It has a combined
+area of 42 square feet, about half of that of
+the Wright elevator, and it is only 4 feet from the
+front edge of the main planes, instead of 10 feet as
+in the Wright machine. A framework nearly square
+in section, and about 25 feet long, extends to the
+rear, and supports a cellular, or box-like, tail, which
+<span class="pagenum" id="Page_88">88</span>
+forms a case in which is the rudder surface for steering
+to right or to left.</p>
+
+<div class="figcenter">
+<img src="images/i_087.jpg" alt="" />
+<p class="caption">Diagram showing details of construction of the Voisin biplane. <i>C</i>, <i>C</i>, the
+curtains forming the stabilizing cells.</p></div>
+
+<p>A distinctive feature of the Voisin biplane is the
+use of four vertical planes, or curtains, between the
+two main planes, forming two nearly square “cells”
+at the ends of the planes.</p>
+
+<p>At the rear of the main planes, in the centre, is
+the single propeller. It is made of steel, two-bladed,
+and is 8 feet 6 inches in diameter. It is coupled
+directly to the shaft of the motor, making with it
+1,200 revolutions per minute. The motor is of the
+V type, developing 50 horse-power, and giving a
+speed of 37 miles per hour.</p>
+
+<div class="figcenter">
+<img src="images/i_088.jpg" alt="" />
+<blockquote>
+
+<p>Diagram showing the simplicity of control of the Voisin machine, all operations
+being performed by the wheel and its sliding axis.</p></blockquote>
+</div>
+
+<p>The controls are all actuated by a rod sliding back
+and forth horizontally in front of the pilot’s seat,
+having a wheel at the end. The elevator is fastened
+to the rod by a crank lever, and is tilted up or down
+as the rod is pushed forward or pulled back. Turning
+<span class="pagenum" id="Page_89">89</span>
+<span class="pagenum" id="Page_90">90</span>
+the wheel from side to side moves the rudder in
+the rear. There are no devices for controlling the
+equilibrium. This is supposed to be maintained automatically
+by the fixed vertical curtains.</p>
+
+<div class="figcenter">
+<img src="images/i_089.jpg" alt="" />
+<blockquote>
+
+<p>Voisin biplanes at the starting line at Rheims in August, 1909. They were flown by Louis Paulhan, who won
+third prize for distance, and Henri Rougier, who won fourth prize for altitude. In the elimination races
+to determine the contestants for the Bennett Cup, Paulhan won second place with the Voisin machine, being
+defeated only by Tissandier with a Wright machine. Other noted aviators who fly the Voisin machine are
+M. Bunau-Varilla and the Baroness de la Roche.</p></blockquote>
+</div>
+
+<p>The machine is mounted on two wheels forward,
+and two smaller wheels under the tail.</p>
+
+<p>This description applies to the standard Voisin
+biplane, which has been in much favor with many
+of the best known aviators. Recently the Voisins
+have brought out a new type in which the propeller
+has been placed in front of the planes, exerting
+a pulling force upon the machine, instead of
+pushing it as in the earlier type. The elevating
+plane has been removed to the rear, and combined
+with the rudder.</p>
+
+<p>A racing type also has been produced, in which
+the vertical curtains have been removed and a parallel
+pair of long, narrow ailerons introduced between
+the main planes on both sides of the centre. This
+machine, it is claimed, has made better than 60 miles
+per hour.</p>
+
+<p>The first Voisin biplane was built for Delagrange,
+and was flown by him with success.
+<span class="pagenum" id="Page_91">91</span></p>
+
+<h3>THE FARMAN BIPLANE.</h3>
+
+<p>The second biplane built by the Voisins went into
+the hands of Henri Farman, who made many flights
+with it. Not being quite satisfied with the machine,
+and having an inventive mind, he was soon building
+a biplane after his own designs, and the Farman biplane
+is now one of the foremost in favor among
+both professional and amateur aviators.</p>
+
+<p>It is decidedly smaller in area of surface than the
+Wright and Voisin machines, having but 430 square
+feet in the two supporting planes. It has a spread
+of 33 feet, and the planes are 7 feet wide, and set 6
+feet apart. In the Farman machine the vertical curtains
+of the Voisin have been dispensed with. The
+forward elevator is there, but raised nearly to the
+level of the upper plane, and placed 9 feet from the
+front edge of the main planes. To control the equilibrium,
+the two back corners of each plane are cut
+and hinged so that they hang vertically when not in
+flight. When in motion these flaps or ailerons
+stream out freely in the wind, assuming such position
+as the speed of the passing air gives them. They
+are pulled down by the pilot at one end or the other,
+as may be necessary to restore equilibrium, acting
+<span class="pagenum" id="Page_92">92</span>
+<span class="pagenum" id="Page_93">93</span>
+in very much the same manner as the warping tips
+of the Wright machine. A pair of tail planes are set
+in parallel on a framework about 20 feet in the rear
+of the main planes, and a double rudder surface behind
+them. Another model has hinged ailerons on
+these tail planes, and a single rudder surface set upright
+between them. These tail ailerons are moved
+in conjunction with those of the main planes.</p>
+
+<div class="figcenter">
+<img src="images/i_092.jpg" alt="" />
+<p class="caption">The Farman biplane, showing the position of the hinged ailerons when at rest. At full speed these surfaces stream out in
+the wind in line with the planes to which they are attached.</p></div>
+
+<div class="figcenter">
+<img src="images/i_093.jpg" alt="" />
+<p class="caption">Diagram of the Farman biplane. A later type has the hinged ailerons also
+on the tail planes.</p></div>
+
+<p>The motor has 4 cylinders, and turns a propeller
+made of wood, 8 feet 6 inches in diameter, at a speed
+of 1,300 revolutions per minute&mdash;nearly three times
+as fast as the speed of the Wright propellers, which
+are about the same size. The propeller is placed just
+under the rear edge of the upper main plane, the
+<span class="pagenum" id="Page_94">94</span>
+lower one being cut away to make room for the revolving
+blades. The motor develops 45 to 50 horse-power,
+and drives the machine at a speed of 41 miles
+per hour.</p>
+
+<p>The “racing Farman” is slightly different, having
+the hinged ailerons only on one of the main
+planes. The reason for this is obvious. Every depression
+of the ailerons acts as a drag on the air
+flowing under the planes, increasing the lift at the
+expense of the speed.</p>
+
+<div class="figcenter">
+<img src="images/i_094.jpg" alt="" />
+<p class="caption">Sketch of Farman machine, showing position of operator. <i>A</i>, <i>A</i>, main planes;
+<i>B</i>, elevator; <i>C</i>, motor; <i>P</i>, tail planes.</p></div>
+
+<p>The whole structure is mounted upon skids with
+wheels attached by a flexible connection. In case
+of a severe jar, the wheels are pushed up against the
+springs until the skids come into play.</p>
+
+<p>The elevator and the wing naps are controlled by
+a lever at the right hand of the pilot. This lever
+moves on a universal joint, the side-to-side movement
+working the flaps, and the forward-and-back
+motion the elevator. Steering to right or left is
+done with a bar operated by the feet.
+<span class="pagenum" id="Page_95">95</span></p>
+
+<div class="figcenter">
+<img src="images/i_095.jpg" alt="" />
+<p class="caption">Henri Farman carrying a passenger across country.
+<span class="pagenum" id="Page_96">96</span></p></div>
+
+<p>Farman has himself made many records with
+his machine, and so have others. With a slightly
+larger and heavier machine than the one described,
+Farman carried two passengers a distance of 35
+miles in one hour.</p>
+
+<h3>THE CURTISS BIPLANE.</h3>
+
+<p>This American rival of the Wright biplane is the
+lightest machine of this type so far constructed. The
+main planes are but 29 feet in spread, and 4 feet 6
+inches in width, and are set not quite 5 feet apart.
+The combined area of the two planes is 250 square
+feet. The main planes are placed midway of the
+length of the fore-and-aft structure, which is nearly
+30 feet. At the forward end is placed the elevator,
+and at the rear end is the tail&mdash;one small plane surface&mdash;and
+the vertical rudder surface in two parts,
+one above and the other below the tail plane. Equilibrium
+is controlled by changing the slant of two
+small balancing planes which are placed midway between
+the main planes at the outer ends, and in line
+with the front edges. These balancing planes are
+moved by a lever standing upright behind the pilot,
+having two arms at its upper end which turn forward
+so as to embrace his shoulders. The lever is
+<span class="pagenum" id="Page_97">97</span>
+<span class="pagenum" id="Page_98">98</span>
+moved to right or to left by the swaying of the pilot’s
+body.</p>
+
+<div class="figcenter">
+<img src="images/i_097.jpg" alt="" />
+<p class="caption">Glenn H. Curtiss in his machine ready to start. The fork of the balancing lever is plainly seen at his shoulders. Behind
+him is the radiator, with the engine still further back.</p></div>
+
+<p>The motor is raised to a position where the shaft
+of the propeller is midway between the levels of the
+main planes, and within the line of the rear edges,
+so that they have to be cut away to allow the passing
+of the blades. The motor is of the V type, with 8
+cylinders. It is 30 horse-power and makes 1,200
+revolutions per minute. The propeller is of steel,
+two-bladed, 6 feet in diameter, and revolves at the
+same speed as the shaft on which it is mounted.
+The high position of the engine permits a low running
+gear. There are two wheels under the rear
+edges of the main planes, and another is placed half-way
+between the main planes and the forward rudder,
+or elevator. A brake, operated by the pilot’s
+foot, acts upon this forward wheel to check the speed
+at the moment of landing.</p>
+
+<p>Another type of Curtiss machine has the ailerons
+set in the rear of the main planes, instead of between
+them.</p>
+
+<p>The Curtiss is the fastest of the biplanes, being
+excelled in speed only by some of the monoplanes.
+It has a record of 51 miles per hour.
+<span class="pagenum" id="Page_99">99</span></p>
+
+<h3>THE CODY BIPLANE.</h3>
+
+<p>The Cody biplane has the distinction of being
+the first successful British aeroplane. It was designed
+and flown by Captain S. F. Cody, at one time
+an American, but for some years an officer in the
+British army.</p>
+
+<p>It is the largest and heaviest of all the biplanes,
+weighing about 1,800 lbs., more than three times
+the weight of the Curtiss machine. Its main planes
+are 52 feet in lateral spread, and 7 feet 6 inches in
+width, and are set 9 feet apart. The combined area
+of these sustaining surfaces is 770 square feet.
+The upper plane is arched, so that the ends of the
+main planes are slightly closer together than at the
+centre.</p>
+
+<p>The elevator is in two parts placed end to end,
+about 12 feet in front of the main planes. They
+have a combined area of 150 square feet. Between
+them and above them is a small rudder for steering
+to right or left in conjunction with the large rudder
+at the rear of the machine. The latter has an area
+of 40 square feet.</p>
+
+<p>There are two small balancing planes, set one at
+each end of the main planes, their centres on the
+<span class="pagenum" id="Page_100">100</span>
+<span class="pagenum" id="Page_101">101</span>
+rear corner struts, so that they project beyond the
+tips of the planes and behind their rear lines.</p>
+
+<div class="figcenter">
+<img src="images/i_100.jpg" alt="" />
+<p class="caption">The Cody biplane in flight. Captain Cody has both hands raised above his head, showing the automatic stability of his machine.</p></div>
+
+<p>The biplane is controlled by a lever rod having
+a wheel at the end. Turning the wheel moves the
+rudders; pushing or pulling the wheel works the
+elevator; moving the wheel from side to side moves
+the balancing planes.</p>
+
+<p>There are two propellers, set one on each side of
+the engine, and well forward between the main
+planes. They are of wood, of the two-bladed type,
+7 feet in diameter. They are geared down to make
+600 revolutions per minute. The motor has 8 cylinders
+and develops 80 horse-power at 1,200 revolutions
+per minute.</p>
+
+<p>The machine is mounted on a wheeled running
+gear, two wheels under the front edge of the main
+planes and one a short distance forward in the centre.
+There is also a small wheel at each extreme end of
+the lower main plane.</p>
+
+<p>The Cody biplane has frequently carried a passenger,
+besides the pilot, and is credited with a
+speed of 38 miles per hour.</p>
+
+<p>The first aeroplane flights ever made in England
+were by Captain Cody on this biplane, January 2,
+1909.
+<span class="pagenum" id="Page_102">102</span></p>
+
+<h3>THE SOMMER BIPLANE.</h3>
+
+<p>The Sommer biplane is closely similar to the Farman
+machine, but has the hinged ailerons only on
+the upper plane. Another difference is that the tail
+has but one surface, and the rudder is hung beneath
+it. Its dimensions are:&mdash;Spread of main planes,
+34 feet; depth (fore-and-aft), 6 feet 8 inches; they
+are set 6 feet apart. The area of the main planes
+is 456 square feet; area of tail, 67 square feet; area
+of rudder, 9 square feet. It is driven by a 50-horsepower
+Gnome motor, turning an 8-foot, two-bladed
+propeller.</p>
+
+<p>M. Sommer has flown with three passengers, a
+total weight of 536 lbs., besides the weight of the
+machine.</p>
+
+<h3>THE BALDWIN BIPLANE.</h3>
+
+<p>The Baldwin biplane, designed by Captain Thomas
+S. Baldwin, the distinguished balloonist, resembles
+the Farman type in some features, and the Curtiss
+in others. It has the Curtiss type of ailerons, set
+between the wings, but extending beyond them laterally.
+The elevator is a single surface placed in
+front of the machine, and the tail is of the biplane
+type with the rudder between. The spread of the
+<span class="pagenum" id="Page_103">103</span>
+main planes is 31 feet 3 inches, and their depth 4
+feet 6 inches. A balancing plane of 9 square feet
+is set upright (like a fin) above the upper main
+plane, on a swivel. This is worked by a fork fitting
+on the shoulders of the pilot, and is designed to restore
+equilibrium by its swinging into head-resistance
+on one side or the other as may be necessary.</p>
+
+<div class="figcenter">
+<img src="images/i_103.jpg" alt="" />
+<p class="caption">The Baldwin biplane, showing balancing plane above upper main plane.</p></div>
+
+<p>The motive power is a 4-cylinder Curtiss motor,
+which turns a propeller 7 feet 6 inches in diameter,
+<span class="pagenum" id="Page_104">104</span>
+set just within the rear line of the main planes, which
+are cut away to clear the propeller blades.</p>
+
+<h3>THE BADDECK BIPLANE.</h3>
+
+<p>The newest biplane of the Aerial Experiment Association
+follows in general contour its successful
+precursor, the “Silver Dart,” with which J. A. D. McCurdy
+made many records. The “Baddeck No. 2”
+is of the biplane type, and both the planes are arched
+toward each other. They have a spread of 40 feet,
+and are 7 feet in depth at the centre, rounding to 5
+feet at the ends, where the wing tips, 5 feet by 5
+feet, are hinged. The elevator is also of the biplane
+type, two surfaces each 12 feet long and 28 inches
+wide, set 30 inches apart. This is mounted 15 feet
+in front of the main planes. The tail is mounted
+11 feet in the rear of the main planes, and is the
+same size and of the same form as the elevator.</p>
+
+<p>The controls are operated by the same devices as
+in the Curtiss machine. The propeller is 7 feet 8
+inches in diameter, and is turned by a six-cylinder
+automobile engine of 40 horse-power running at
+1,400 revolutions per minute. The propeller is
+geared down to run at 850 revolutions per minute.
+<span class="pagenum" id="Page_105">105</span>
+The motor is placed low down on the lower plane,
+but the propeller shaft is raised to a position as
+nearly as possible that of the centre of resistance of
+the machine. The speed attained is 40 miles per
+hour.</p>
+
+<div class="figcenter">
+<img src="images/i_105.jpg" alt="" />
+<p class="caption">The McCurdy biplane, “Baddeck No. 2.”</p></div>
+
+<p>A unique feature of the mechanism is the radiator,
+which is built of 30 flattened tubes 7 feet 6
+inches long, and 3 inches wide, and very thin. They
+are curved from front to rear like the main planes,
+and give sufficient lift to sustain their own weight
+<span class="pagenum" id="Page_106">106</span>
+and that of the water carried for cooling the cylinders.
+The running gear is of three wheels placed
+as in the Curtiss machine. The “Baddeck No. 2”
+has made many satisfactory flights with one passenger
+besides the pilot.</p>
+
+<h3>THE HERRING BIPLANE.</h3>
+
+<p>At the Boston Aircraft Exhibition in February,
+1910, the Herring biplane attracted much attention,
+not only because of its superiority of mechanical
+finish, but also on account of its six triangular stabilizing
+fins set upright on the upper plane. Subsequent
+trials proved that this machine was quite
+out of the ordinary in action. It rose into the air
+after a run of but 85 feet, and at a speed of only
+22 miles per hour, and made a 40-degree turn at a
+tipping angle of 20 degrees. As measured by the
+inventor, the machine rose in the air with the pilot
+(weighing 190 lbs.), with a thrust of 140 lbs., and
+required only a thrust of from 80 to 85 lbs. to keep
+it flying.</p>
+
+<p>The spread of the planes is 28 feet, and they are
+4 feet in depth, with a total supporting surface of
+220 feet. A 25 horse-power Curtiss motor turns a
+4-bladed propeller of 6 feet diameter and 5-foot pitch
+<span class="pagenum" id="Page_107">107</span>
+<span class="pagenum" id="Page_108">108</span>
+(designed by Mr. Herring) at the rate of 1,200 revolutions
+per minute.</p>
+
+<div class="figcenter">
+<img src="images/i_107.jpg" alt="" />
+<p class="caption">The L. A. W. (League of American Wheelmen) biplane at the Boston Aircraft Exhibition, February, 1910. Note the peculiar
+curve of the divided planes. The motor is of the rotating type, of 50 horse-power.</p></div>
+
+<p>The elevator consists of a pair of parallel surfaces
+set upon hollow poles 12 feet in front of the main
+planes. The tail is a single surface.</p>
+
+<p>The stabilizing fins act in this manner: when the
+machine tips to one side, it has a tendency to slide
+down an incline of air toward the ground. The fins
+offer resistance to this sliding, retarding the upper
+plane, while the lower plane slides on and swings as
+a pendulum into equilibrium again.</p>
+
+<h3>THE BREGUET BIPLANE.</h3>
+
+<p>The Breguet biplane is conspicuous in having a
+biplane tail of so large an area as to merit for the
+machine the title “tandem biplane.” The main
+planes have a spread of 41 feet 8 inches, and an area
+of 500 square feet. The tail spreads 24 feet, and
+its area is about 280 square feet. The propeller is
+three-bladed, 8 feet in diameter, and revolves at a
+speed of 1,200 revolutions per minute. It is placed
+in front of the main plane, after the fashion of the
+monoplanes. The motive power is an 8-cylinder
+R-E-P engine, developing 55 horse-power.
+<span class="pagenum" id="Page_109">109</span></p>
+
+<div class="figcenter">
+<img src="images/i_109.jpg" alt="" />
+<p class="small"><i>Courtesy of N. Y. Sun.</i></p>
+<blockquote>
+
+<p class="caption">The Seddon tandem biplane, constructed by Lieutenant Seddon of the British Navy. The area of its planes is 2,000 square feet.
+Compare its size with that of the monoplane in the background. It is intended to carry ten persons.
+<span class="pagenum" id="Page_110">110</span></p></blockquote>
+</div>
+
+<div class="figcenter">
+<img src="images/i_110.jpg" alt="" />
+
+<p class="table w100">
+<span class="tcell tdc">Wright biplane.</span>
+<span class="tcell tdc">Curtiss biplane.</span>
+</p>
+
+<p class="caption">Comparative build and area of prominent American biplanes.
+<span class="pagenum" id="Page_111">111</span></p>
+</div>
+
+<div class="figcenter">
+<img src="images/i_111.jpg" alt="" />
+
+<p class="table w100">
+<span class="tcell tdc">Voisin biplane.</span>
+<span class="tcell tdc">Breguet biplane.</span>
+</p>
+
+<p class="caption">Comparative build and area of prominent European biplanes.
+<span class="pagenum" id="Page_112">112</span></p></div>
+
+<hr class="chap" />
+
+<h2 id="Chapter_VI">Chapter VI.<br />
+
+FLYING MACHINES: THE MONOPLANE.</h2>
+
+<blockquote>
+
+<p>The common goal&mdash;Interchanging features&mdash;The Bleriot machine&mdash;First
+independent flyer&mdash;Construction and controls&mdash;The
+“Antoinette”&mdash;Large area&mdash;Great stability&mdash;Santos-Dumont’s
+monoplane&mdash;Diminutive size&mdash;R-E-P monoplane&mdash;encased
+structure&mdash;Hanriot machine&mdash;Boat body&mdash;Sturdy
+build&mdash;Pfitzner machine&mdash;Lateral type&mdash;Thrusting
+propeller&mdash;Fairchild, Burlingame, Cromley, Chauviere,
+Vendome, and Moisant monoplanes.</p></blockquote>
+
+<p class="drop"><span class="uppercase">In</span> all the ardent striving of the aviators to beat
+each other’s records, a surprisingly small amount
+of personal rivalry has been developed. Doubtless
+this is partly because their efforts to perform definite
+feats have been absorbing; but it must also be that
+these men, who know that they face a possible fall in
+every flight they make, realize that their competitors
+are as brave as themselves in the face of the same
+danger; and that they are actually accomplishing
+marvellous wonders even if they do no more than just
+escape disastrous failure. Certain it is that each,
+realizing the tremendous difficulties all must overcome,
+respects the others’ ability and attainments.
+<span class="pagenum" id="Page_113">113</span></p>
+
+<p>Consequently we do not find among them two distinctly
+divergent schools of adherents, one composed
+of the biplanists, the other of the monoplanists. Nor
+are the two types of machines separated in this book
+for any other purpose than to secure a clearer understanding
+of what is being achieved by all types in the
+progress toward the one common goal&mdash;the flight of
+man.</p>
+
+<p>The distinctive feature of the monoplane is that
+it has but one main plane, or spread of surface, as
+contrasted with the two planes, one above the other,
+of the biplane. Besides the main plane, it has a secondary
+plane in the rear, called the tail. The office
+of this tail is primarily to secure longitudinal, or
+fore-and-aft, balance; but the secondary plane has
+been so constructed that it is movable on a horizontal
+axis, and is used to steer the machine upward or
+downward. While most of the biplanes now have a
+horizontal tail-plane, they were not at first so provided,
+but carried the secondary plane (or planes) in
+front of the main planes. Even in the latest type
+brought out by the conservative Wright brothers, the
+former large-surfaced elevator in front has been removed,
+and a much smaller tail-plane has been added
+in the rear, performing the same function of steering
+<span class="pagenum" id="Page_114">114</span>
+the machine up or down, but also providing the fore-and-aft
+stabilizing feature formerly peculiar to the
+monoplane. Another feature heretofore distinctively
+belonging to the monoplane has been adopted by some
+of the newer biplanes, that of the traction propeller&mdash;pulling
+the machine behind it through the air, instead
+of pushing it along by a thrusting propeller
+placed behind the main planes.</p>
+
+<p>The continual multiplication of new forms of the
+monoplane makes it possible to notice only those
+which exhibit the wider differences.</p>
+
+<h3>THE BLERIOT MONOPLANE.</h3>
+
+<p>The Bleriot monoplane has the distinction of
+being the first wholly successful flying machine.
+Although the Wright machine was making flights
+years before the Bleriot had been built, it was still
+dependent upon a starting device to enable it to leave
+the ground. That is, the Wright machine was not
+complete in itself, and was entirely helpless at even
+a short distance from its starting tower, rail, and car,
+which it was unable to carry along. Because of its
+completeness, M. Bleriot was able to drive his machine
+from Toury to Artenay, France (a distance of
+<span class="pagenum" id="Page_115">115</span>
+<span class="pagenum" id="Page_116">116</span>
+8¾ miles) on October 31, 1908, make a landing, start
+on the return trip, make a second landing, and again
+continue his journey back to Toury, all under his
+own unassisted power. This feat was impossible to
+the Wright machine as it was then constructed, thus
+leaving the Bleriot monoplane in undisputed pre-eminence
+in the history of aviation.</p>
+
+<div class="figcenter">
+<img src="images/i_115.jpg" alt="" />
+<p class="caption">A Bleriot monoplane, “No. XI,” in flight.</p></div>
+
+<p>At a little distance, where the details of construction
+are not visible, the Bleriot machine has the appearance
+of a gigantic bird. The sustaining surface,
+consisting of a single plane, is divided into two wings
+made of a stiff parchment-like material, mounted one
+on each side of a framework of the body, which is
+built of mahogany and whitewood trussed with diagonal
+ties of steel wire.</p>
+
+<p>The main plane has a lateral spread of 28 feet
+and a depth of 6 feet, and is rounded at the ends. It
+has an area of about 150 square feet, and is slightly
+concave on the under side. The tail-plane is 6 feet
+long and 2 feet 8 inches in depth; at its ends are
+the elevators, consisting of pivoted wing tips each
+about 2 feet 6 inches square with rounded extremities.
+The rudder for steering to left or right is
+mounted at the extreme rear end of the body, and has
+an area of 9 square feet.
+<span class="pagenum" id="Page_117">117</span></p>
+
+<div class="figcenter">
+<img src="images/i_117.jpg" alt="" />
+<p class="caption">The Bleriot “No. XII.,” showing new form of tail, and the complete encasing with fabric.
+<span class="pagenum" id="Page_118">118</span></p></div>
+
+<p>The body is framed nearly square in front and
+tapers to a wedge-like edge at the rear. It extends
+far enough in front of the main plane to give room
+for the motor and propeller. The seat for the pilot
+is on a line with the rear edge of the main plane, and
+above it. The forward part of the body is enclosed
+with fabric.</p>
+
+<div class="figcenter">
+<img src="images/i_118.jpg" alt="" />
+<p class="caption">Forward chassis of Bleriot monoplane, showing caster mounting of wheels.
+The framing of the body is shown by the dotted lines.</p></div>
+
+<p>The machine is mounted on three wheels attached
+<span class="pagenum" id="Page_119">119</span>
+to the body: two at the front, with a powerful spring
+suspension and pivoted like a caster, and the other
+rigidly at a point just forward of the rudders.</p>
+
+<p>The lateral balance is restored by warping the tips
+of the main plane; if necessary, the elevator tips at
+the rear may be operated to assist in this. All the
+controls are actuated by a single lever and a drum
+to which the several wires are attached.</p>
+
+<div class="figcenter">
+<img src="images/i_119.jpg" alt="" />
+<blockquote>
+
+<p>Diagram of Bleriot “No. XI.,” from the rear. <i>A</i>, <i>A</i>, main plane; <i>B</i>, tail; <i>C</i>,
+body; <i>D</i>, <i>D</i>, wing tips of tail; <i>E</i>, rudder; <i>H</i>, propeller; <i>M</i>, motor; <i>O</i>, axis
+of wing tips; <i>R</i>, radiator; <i>a</i>, <i>a</i>, <i>b</i>, <i>b</i>, spars of wings; <i>h</i>, <i>h</i>, guy wires;
+<i>p</i>, <i>k</i>, truss.</p></blockquote>
+</div>
+
+<p>The motors used on the Bleriot machines have varied
+in type and power. In the “No. XI.,” with
+which M. Bleriot crossed the English Channel, the
+motor was a 3-cylinder Anzani engine, developing
+24 horse-power at 1,200 revolutions per minute. The
+<span class="pagenum" id="Page_120">120</span>
+propeller was of wood, 2-bladed, and 6 feet 9 inches
+in diameter. It was mounted directly on the shaft,
+and revolved at the same speed, giving the machine
+a velocity of 37 miles per hour. This model has
+also been fitted with a 30 horse-power R-E-P (R.
+Esnault-Pelterie) motor, having 7 cylinders. The
+heavier type “No. XII.” has been fitted with the
+50 horse-power Antoinette 8-cylinder engine, or the
+7-cylinder rotating Gnome engine, also of 50 horse-power.</p>
+
+<div class="figcenter">
+<img src="images/i_120.jpg" alt="" />
+<p class="caption">Sketches showing relative size, construction, and position of pilot in the
+Bleriot machines; “No. XI.” (the upper), and “No. XII.” (the lower).
+<span class="pagenum" id="Page_121">121</span></p></div>
+
+<p>The total weight of the “No. XI.” monoplane is
+462 pounds, without the pilot.</p>
+
+<h3>THE ANTOINETTE MONOPLANE.</h3>
+
+<p>The Antoinette is the largest and heaviest of the
+monoplanes. It was designed by M. Levavasseur,
+and has proved to be one of the most remarkable of
+the aeroplanes by its performances under adverse conditions;
+notably, the flight of Hubert Latham in a
+gale of 40 miles per hour at Blackpool in October,
+1909.</p>
+
+<p>The Antoinette has a spread of 46 feet, the surface
+being disposed in two wings set at a dihedral
+angle; that is, the outer ends of the wings incline
+upward from their level at the body, so that at the
+front they present the appearance of a very wide open
+“V.” These wings are trapezoidal in form, with the
+wider base attached to the body, where they are 10
+feet in depth (fore and aft). They are 7 feet in
+depth at the tips, and have a total combined area of
+377 square feet. The great depth of the wings requires
+that they be made proportionally thick to be
+strong enough to hold their form. Two trussed
+spars are used in each wing, with a short mast on
+each, half-way to the tip, reaching below the wing
+<span class="pagenum" id="Page_122">122</span>
+<span class="pagenum" id="Page_123">123</span>
+as well as above it. To these are fastened guy wires,
+making each wing an independent truss. A mast
+on the body gives attachment for guys which bind
+the whole into a light and rigid construction. The
+framework of the wings is covered on both sides with
+varnished fabric.</p>
+
+<div class="figcenter">
+<img src="images/i_122.jpg" alt="" />
+<p class="caption">The Antoinette monoplane in flight.</p></div>
+
+<p>The body is of triangular section. It is a long
+girder; at the front, in the form of a pyramid, expanding
+to a prism at the wings, and tapering toward
+the tail. It is completely covered with the fabric,
+which is given several coats of varnish to secure the
+minimum of skin friction.</p>
+
+<div class="figcenter">
+<img src="images/i_123.jpg" alt="" />
+<p class="caption">Diagram showing construction of the Antoinette monoplane.</p></div>
+
+<p>The tail is 13 feet long and 9 feet wide, in the
+form of a diamond-shaped kite. The rear part
+of it is hinged to be operated as the elevator. There
+<span class="pagenum" id="Page_124">124</span>
+is a vertical stabilizing fin set at right angles to the
+rigid part of the tail. The rudder for steering to
+right or left is in two triangular sections, one above
+and the other below the tail-plane. The entire length
+of the machine is 40 feet, and its weight is 1,045
+pounds.</p>
+
+<p>It is fitted with a motor of the “V” type, having
+8 cylinders, and turning a 2-bladed steel propeller
+1,100 revolutions per minute, developing from 50
+to 55 horse-power.</p>
+
+<p>The control of the lateral balance is by ailerons
+attached to the rear edges of the wings at their outer
+ends. These are hinged, and may be raised as well
+as lowered as occasion demands, working in opposite
+directions, and thus doubling the effect of similar
+ailerons on the Farman machine, which can only be
+pulled downward.</p>
+
+<p>The machine is mounted on two wheels under the
+centre of the main plane, with a flexible wood skid
+projecting forward. Another skid is set under the
+tail.</p>
+
+<p>It is claimed for the Antoinette machine that its
+inherent stability makes it one of the easiest of all
+for the beginner in aviation. With as few as five
+lessons many pupils have become qualified pilots, even
+<span class="pagenum" id="Page_125">125</span>
+<span class="pagenum" id="Page_126">126</span>
+winning prizes against competitors of much wider
+experience.</p>
+
+<div class="figcenter">
+<img src="images/i_125.jpg" alt="" />
+<p class="caption">Diagrams showing comparative size and position of surfaces and structure of the Bleriot (left) and Antoinette
+(right) monoplanes.</p></div>
+
+<h3>THE SANTOS-DUMONT MONOPLANE.</h3>
+
+<p>This little machine may be called the “runabout”
+of the aeroplanes. It has a spread of only 18 feet,
+and is but 20 feet in total length. Its weight is
+about 245 pounds.</p>
+
+<p>The main plane is divided into two wings, which
+are set at the body at a dihedral angle, but curve
+downward toward the tips, forming an arch. The
+depth of the wings at the tips is 6 feet. For a space
+on each side of the centre they are cut away to 5
+feet in depth, to allow the propeller to be set within
+their forward edge. The total area of the main plane
+is 110 square feet.</p>
+
+<p>The tail-plane is composed of a vertical surface
+and a horizontal surface intersecting. It is arranged
+so that it may be tilted up or down to serve as an
+elevator, or from side to side as a rudder. Its horizontal
+surface has an area of about 12 square feet.</p>
+
+<p>The engine is placed above the main plane and the
+pilot’s seat below it. The body is triangular in section,
+with the apex uppermost, composed of three
+strong bamboo poles with cross-pieces held in place by
+aluminum sockets, and cross braced with piano wire.
+<span class="pagenum" id="Page_127">127</span></p>
+
+<div class="figcenter">
+<img src="images/i_127.jpg" alt="" />
+<p class="caption">Santos-Dumont’s <i>La Demoiselle</i> in flight.</p></div>
+
+<p>The motor is of the opposed type, made by Darracq,
+weighing only 66 pounds, and developing 30
+horse-power at 1,500 revolutions per minute. The
+propeller is of wood, 2-bladed, and being mounted
+<span class="pagenum" id="Page_128">128</span>
+directly on the shaft of the motor, revolves at the
+same velocity. The speed of the Santos-Dumont
+machine is 37 miles per hour.</p>
+
+<div class="figcenter">
+<img src="images/i_128.jpg" alt="" />
+<p class="caption">The Darracq motor and propeller of the Santos-Dumont machine. The
+conical tank in the rear of the pilot’s seat holds the gasoline.</p></div>
+
+<p>The lateral balance is preserved by a lever which
+extends upward and enters a long pocket sewed on
+the back of the pilot’s coat. His leaning from side
+<span class="pagenum" id="Page_129">129</span>
+to side warps the rear edges of the wings at their
+tips. The elevator is moved by a lever, and the rudder
+by turning a wheel.</p>
+
+<p>While this machine has not made any extended
+flights, Santos-Dumont has travelled in the aggregate
+upward of 2,000 miles in one or another of this type.</p>
+
+<p>The plans, with full permission to any one to build
+from them, he gave to the public as his contribution
+to the advancement of aviation. Several manufacturers
+are supplying them at a cost much below that
+of an automobile.</p>
+
+<div class="figcenter">
+<img src="images/i_129.jpg" alt="" />
+<p class="caption">Sketch showing position of pilot in Santos-Dumont machine. <i>A</i>, main plane;
+<i>B</i>, tail plane; <i>C</i>, motor.</p></div>
+
+<h3>THE R-E-P MONOPLANE.</h3>
+
+<p>The Robert Esnault-Pelterie (abbreviated by its
+inventor to R-E-P) monoplane, viewed from above,
+bears a striking resemblance to a bird with a fan-shaped
+tail. It is much shorter in proportion to its
+spread than any other monoplane, and the body being
+<span class="pagenum" id="Page_130">130</span>
+entirely covered with fabric, it has quite a distinct
+appearance.</p>
+
+<p>The plane is divided into two wings, in form very
+much like the wings of the Antoinette machine.
+Their spread, however, is but 35 feet. Their depth
+at the body is 8 feet 6 inches, and at the tips, 5 feet.
+Their total combined area is 226 square feet.</p>
+
+<p>The body of the R-E-P machine has much the appearance
+of a boat, being wide at the top and coming
+to a sharp keel below. The boat-like prow in front
+adds to this resemblance. As the body is encased
+in fabric, these surfaces aid in maintaining vertical
+stability.</p>
+
+<p>A large stabilizing fin extends from the pilot’s seat
+to the tail. The tail is comparatively large, having
+an area of 64 square feet. Its rear edge may be
+raised or lowered to serve as an elevator. The rudder
+for steering to right or left is set below in the
+line of the body, as in a boat. It is peculiar in that
+it is of the “compensated” type; that is, pivoted
+near the middle of its length, instead of at the forward
+end.</p>
+
+<p>The control of the lateral balance is through warping
+the wings. This is by means of a lever at the
+left hand of the pilot, with a motion from side to side.
+<span class="pagenum" id="Page_131">131</span>
+The same lever moved forward or backward controls
+the elevator. The steering lever is in front of
+the pilot’s seat, and moves to right or to left.</p>
+
+<table class="images">
+  <tr>
+    <td class="w50"><img src="images/i_131a.jpg" alt="" /></td>
+    <td class="w50">Elevation, showing large stabilizing
+    fin; boat-like body encased in fabric;
+    and compensated rudder, pivoted
+    at the rear end of the fin.</td>
+  </tr>
+  <tr>
+    <td class="w50"><img src="images/i_131b.jpg" alt="" /></td>
+    <td class="w50">Plan, showing comparative spread
+    of surfaces, and the attachment of
+    wheels at the wing tips.</td>
+  </tr>
+  <tr>
+    <td colspan="2"><p class="caption">Graphic sketch showing elevation and plan of the R-E-P monoplane.</p></td>
+  </tr>
+</table>
+
+<p>The motor is an invention of M. Esnault-Pelterie,
+and may be of 5, 7, or 10 cylinders, according to
+the power desired. The cylinders are arranged
+in two ranks, one in the rear of the other, radiating
+outward from the shaft like spokes in a wheel.
+The propeller is of steel, 4-bladed, and revolves at
+1,400 revolutions per minute, developing 35 horse-power,
+<span class="pagenum" id="Page_132">132</span>
+and drawing the machine through the air at
+a speed of 47 miles per hour.</p>
+
+<h3>THE HANRIOT MONOPLANE.</h3>
+
+<p>Among the more familiar machines which have
+been contesting for records at the various European
+meets during the season of 1910, the Hanriot monoplane
+earned notice for itself and its two pilots, one
+of them the fifteen-year-old son of the inventor. At
+Budapest the Hanriot machine carried off the honors
+of the occasion with a total of 106 points for “best
+performances,” as against 84 points for the Antoinette,
+and 77 points for the Farman biplane. A
+description of its unusual features will be of interest
+by way of comparison.</p>
+
+<p>In general appearance it is a cross between the
+Bleriot and the Antoinette, the wings being shaped
+more like the latter, but rounded at the rear of the
+tips like the Bleriot. Its chief peculiarity is in the
+body of the machine, which is in form very similar
+to a racing shell&mdash;of course with alterations to suit
+the requirements of the aeroplane. Its forward
+part is of thin mahogany, fastened upon ash ribs,
+with a steel plate covering the prow. The rear part
+of the machine is covered simply with fabric.
+<span class="pagenum" id="Page_133">133</span></p>
+
+<p>The spread of the plane is 24 feet 7 inches,
+and it has an area of 170 square feet. The length of
+the machine, fore-and-aft, is 23 feet. Its weight is
+463 pounds. It is mounted on a chassis having both
+wheels and skids, somewhat like that of the Farman
+running gear, but with two wheels instead of four.</p>
+
+<p>The Hanriot machine is sturdily built all the way
+through, and has endured without damage some serious
+falls and collisions which would have wrecked
+another machine.</p>
+
+<p>It is fitted either with a Darracq or a Clerget motor,
+and speeds at about 44 miles per hour.</p>
+
+<h3>THE PFITZNER MONOPLANE.</h3>
+
+<p>The Pfitzner monoplane has the distinction of
+being the first American machine of the single-plane
+type. It was designed and flown by the late Lieut.
+A. L. Pfitzner, and, though meeting with many mishaps,
+has proved itself worthy of notice by its performances,
+through making use of an entirely new
+device for lateral stability. This is the sliding wing
+tip, by which the wing that tends to fall from its
+proper level may be lengthened by 15 inches, the
+other wing being shortened as much at the same time.
+<span class="pagenum" id="Page_134">134</span></p>
+
+<p>There is no longitudinal structure, as in the other
+monoplanes, the construction being transverse and
+built upon four masts set in the form of a square,
+6 feet apart, about the centre. These are braced
+by diagonal struts, and tied with wires on the edges
+of the squares. They also support the guys reaching
+out to the tips of the wings.</p>
+
+<div class="figcenter">
+<img src="images/i_134.jpg" alt="" />
+<blockquote>
+
+<p>The Pfitzner monoplane from the rear, showing the sliding wing tips; dihedral
+angle of the wings; square body; and transverse trussed construction.</p></blockquote>
+</div>
+
+<p>The plane proper is 31 feet in spread, to which
+the wing tips add 2½ feet, and is 6 feet deep, giving
+a total area of 200 square feet. A light framework
+extending 10 feet in the rear carries a tail-plane 6
+<span class="pagenum" id="Page_135">135</span>
+<span class="pagenum" id="Page_136">136</span>
+feet in spread and 2 feet in depth. Both the elevator
+and the rudder planes are carried on a similar framework,
+14 feet in front of the main plane.</p>
+
+<div class="figcenter">
+<img src="images/i_135.jpg" alt="" />
+<p class="caption">The Pfitzner monoplane, showing the structure of the body; the two conical gasoline tanks above;
+the propeller in the rear. Lieutenant Pfitzner at the wheel.</p></div>
+
+<p>The wings of the main plane incline upward from
+the centre toward the tips, and are trussed by vertical
+struts and diagonal ties.</p>
+
+<p>The motor is placed in the rear of the plane, instead
+of in front, as in all other monoplanes. It is
+a 4-cylinder Curtiss motor, turning a 6-foot propeller
+at 1,200 revolutions per minute, and developing 25
+horse-power.</p>
+
+<p>The Pfitzner machine has proved very speedy, and
+has made some remarkably sharp turns on an even
+keel.</p>
+
+<h3>OTHER MONOPLANES.</h3>
+
+<p>Several machines of the monoplane type have been
+produced, having some feature distinct from existing
+forms. While all of these have flown successfully,
+few of them have made any effort to be classed among
+the contestants for honors at the various meets.</p>
+
+<p>One of these, the Fairchild monoplane, shows resemblances
+to the R-E-P, the Antoinette, and the
+Bleriot machines, but differs from them all in having
+two propellers instead of one; and these revolve in
+<span class="pagenum" id="Page_137">137</span>
+the same direction, instead of in contrary directions,
+as do those of all other aeroplanes so equipped. The
+inventor claims that there is little perceptible gyroscopic
+effect with a single propeller, and even less
+with two. The propeller shafts are on the level of
+the plane, but the motor is set about 5 feet below,
+connections being made by a chain drive.</p>
+
+<div class="figcenter">
+<img src="images/i_137.jpg" alt="" />
+<p class="caption">The Beach type of the Antoinette, an American modification of the French
+machine, at the Boston Exhibition, 1910.</p></div>
+
+<p>The Burlingame monoplane has several peculiarities.
+Its main plane is divided into two wings, each
+<span class="pagenum" id="Page_138">138</span>
+10 feet in spread and 5 feet in depth, and set 18
+inches apart at the body. They are perfectly rigid.
+The tail is in two sections, each 4 feet by 5 feet, and
+set with a gap of 6 feet between the sections, in which
+the rudder is placed. Thus the spread of the tail
+from tip to tip is 16 feet, as compared with the 21½
+foot spread of the main plane. The sections of the
+tail are operated independently, and are made to serve
+as ailerons to control the lateral balance, and also
+as the elevator.</p>
+
+<p>The Cromley monoplane, another American machine,
+is modelled after the Santos-Dumont <i>Demoiselle</i>.
+It has a main plane divided into two wings,
+each 9 feet by 6 feet 6 inches, with a gap of 2 feet
+between at the body; the total area being 117 square
+feet. At the rear of the outer ends are hinged
+ailerons, like those of the Farman biplane, to control
+the lateral balance. The tail is 12 feet in the rear,
+and is of the “box” type, with two horizontal surfaces
+and two vertical surfaces. This is mounted
+with a universal joint, so that it can be moved in
+any desired direction. The complete structure, without
+the motor, weighs but 60 pounds.</p>
+
+<p>The Chauviere monoplane is distinct in having a
+rigid spar for the front of the plane, but no ribs.
+<span class="pagenum" id="Page_139">139</span>
+The surface is allowed to spread out as a sail and
+take form from the wind passing beneath. The rear
+edges may be pulled down at will to control the lateral
+balance. It is driven by twin screws set far back
+on the body, nearly to the tail.</p>
+
+<div class="figcenter">
+<img src="images/i_139.jpg" alt="" />
+<blockquote>
+
+<p>The Morok monoplane at the Boston Exhibition. It has the body of the
+Bleriot, the wings of the Santos-Dumont, and the sliding wing tips of
+the Pfitzner.</p></blockquote>
+</div>
+
+<p>The smallest and lightest monoplane in practical
+use is that of M. Raoul Vendome. It is but 16 feet
+in spread, and is 16 feet fore and aft. It is equipped
+with a 12 horse-power motor, and flies at a speed of
+nearly 60 miles per hour. Without the pilot, its
+<span class="pagenum" id="Page_140">140</span>
+entire weight is but 180 pounds. The wings are
+pivoted so that their whole structure may be tilted
+to secure lateral balance.</p>
+
+<p>The new Moisant monoplane is built wholly of
+metal. The structure throughout is of steel, and the
+surfaces of sheet aluminum in a succession of small
+arches from the centre to the tips. No authentic reports
+of its performances are available.</p>
+
+<p>In the Tatin monoplane, also called the Bayard-Clement,
+the main plane is oval in outline, and the
+tail a smaller oval. The surfaces are curved upward
+toward the tips for nearly half their length in both
+the main plane and the tail. The propeller is 8½ feet
+in diameter, and is turned by a Clerget motor, which
+can be made to develop 60 horse-power for starting
+the machine into the air, and then cut down to 30
+horse-power to maintain the flight.
+<span class="pagenum" id="Page_141">141</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_VII">Chapter VII.<br />
+
+FLYING MACHINES: OTHER FORMS.</h2>
+
+<blockquote>
+
+<p>The triplane&mdash;The quadruplane&mdash;The multiplane&mdash;Helicopters&mdash;Their
+principle&mdash;Obstacles to be overcome&mdash;The Cornu
+helicopter&mdash;The Leger helicopter&mdash;The Davidson gyropter&mdash;The
+Breguet gyroplane&mdash;The de la Hault ornithopter&mdash;The
+Bell tetrahedrons&mdash;The Russ flyer.</p></blockquote>
+
+<p class="drop"><span class="uppercase">While</span> the efforts of inventors have been
+principally along the lines of the successful
+monoplanes and biplanes, genius and energy have
+also been active in other directions. Some of these
+other designs are not much more than variations
+from prevailing types, however.</p>
+
+<p>Among these is the English Roe triplane, which is
+but a biplane with an extra plane added; the depths
+of all being reduced to give approximately the same
+surface as the biplane of the same carrying power.
+The tail is also of the triplane type, and has a combined
+area of 160 square feet&mdash;just half that of the
+main planes. The triplane type has long been familiar
+to Americans in the three-decker glider used extensively
+<span class="pagenum" id="Page_142">142</span>
+by Octave Chanute in his long series of
+experiments at Chicago.</p>
+
+<div class="figcenter">
+<img src="images/i_142.jpg" alt="" />
+<p class="caption">The Roe triplane in flight.</p></div>
+
+<p>The quadruplane of Colonel Baden-Powell, also
+an English type, is practically the biplane with unusually
+large forward and tail planes.</p>
+
+<p>The multiplane of Sir Hiram Maxim should also
+be remembered, although he never permitted it to
+have free flight. His new multiplane, modelled after
+the former one, but equipped with an improved gasoline
+<span class="pagenum" id="Page_143">143</span>
+motor instead of the heavy steam-engine of the
+first model, will doubtless be put to a practical test
+when experiments with it are completed.</p>
+
+<div class="figcenter">
+<img src="images/i_143.jpg" alt="" />
+<p class="caption">Sir Hiram Maxim standing beside his huge multiplane.</p></div>
+
+<p>Quite apart from these variants of the aeroplanes
+are the helicopters, ornithopters, gyropters, gyroplanes,
+and tetrahedral machines.</p>
+
+<h3>HELICOPTERS.</h3>
+
+<p>The result aimed at in the helicopter is the ability
+to rise vertically from the starting point, instead of
+<span class="pagenum" id="Page_144">144</span>
+first running along the ground for from 100 to 300
+feet before sufficient speed to rise is attained, as the
+aeroplanes do. The device employed to accomplish
+this result is a propeller, or propellers, revolving horizontally
+above the machine. After the desired altitude
+is gained it is proposed to travel in any direction
+by changing the plane in which the propellers
+revolve to one having a small angle with the horizon.</p>
+
+<div class="figcenter">
+<img src="images/i_144.jpg" alt="" />
+<blockquote>
+
+<p>The force necessary to keep the aeroplane moving in its horizontal path is the
+same as that required to move the automobile of equal weight up the same
+gradient&mdash;much less than its total weight.</p></blockquote>
+</div>
+
+<p>The great difficulty encountered with this type of
+machine is that the propellers must lift the entire
+weight. In the case of the aeroplane, the power of
+the engine is used to slide the plane up an incline of
+air, and for this much less power is required. For
+instance, the weight of a Curtiss biplane with the
+pilot on board is about 700 pounds, and this weight
+<span class="pagenum" id="Page_145">145</span>
+is easily slid up an inclined plane of air with a
+propeller thrust of about 240 pounds.</p>
+
+<p>Another difficulty is that the helicopter screws, in
+running at the start before they can attain speed sufficient
+to lift their load, have established downward
+currents of air with great velocity, in which the
+screws must run with much less efficiency. With
+the aeroplanes, on the contrary, their running gear
+enables them to run forward on the ground almost
+with the first revolution of the propeller, and as they
+increase their speed the currents&mdash;technically called
+the “slip”&mdash;become less and less as the engine speed
+increases.</p>
+
+<p>In the Cornu helicopter, which perhaps has come
+nearer to successful flight than any other, these
+downward currents are checked by interposing
+planes below, set at an angle determined by the operator.
+The glancing of the currents of air from the
+planes is expected to drive the helicopter horizontally
+through the air. At the same time these planes offer
+a large degree of resistance, and the engine power
+must be still further increased to overcome this,
+while preserving the lift of the entire weight. With
+an 8-cylinder Antoinette motor, said to be but 24
+horse-power, turning two 20-foot propellers, the machine
+<span class="pagenum" id="Page_146">146</span>
+is reported as lifting itself and two persons&mdash;a
+total weight of 723 pounds&mdash;to a height of 5
+feet, and sustaining itself for 1 minute. Upon the
+interposing of the planes to produce the horizontal
+motion the machine came immediately to the ground.</p>
+
+<div class="figcenter">
+<img src="images/i_146.jpg" alt="" />
+<p class="caption">Diagram showing principle of the Cornu helicopter. <i>P</i>, <i>P</i>, propelling planes.
+The arrow shows direction of travel with planes at angle shown.</p></div>
+
+<p>This performance must necessarily be compared
+with that of the aeroplanes, as, for instance, the
+Wright machine, which, with a 25 to 30 horse-power
+motor operating two 8-foot propellers, raises a weight
+of 1,050 pounds and propels it at a speed of 40 miles
+an hour for upward of 2 hours.</p>
+
+<p>Another form of helicopter is the Leger machine,
+so named after its French inventor. It has two propellers
+which revolve on the same vertical axis, the
+shaft of one being tubular, encasing that of the other.
+By suitable gearing this vertical shaft may be inclined
+<span class="pagenum" id="Page_147">147</span>
+<span class="pagenum" id="Page_148">148</span>
+after the machine is in the air in the direction
+in which it is desired to travel.</p>
+
+<div class="figcenter">
+<img src="images/i_147.jpg" alt="" />
+<p class="caption">The Vitton-Huber helicopter at the Paris aeronautical salon in 1909. It has the double concentric axis of
+the Leger helicopter and the propelling planes of the Cornu machine.</p></div>
+
+<p>The gyropter differs from the Cornu type of helicopter
+in degree rather than in kind. In the Scotch
+machine, known as the Davidson gyropter, the propellers
+have the form of immense umbrellas made up
+of curving slats. The frame of the structure has the
+shape of a T, one of the gyropters being attached to
+each of the arms of the T. The axes upon which the
+gyropters revolve may be inclined so that their power
+may be exerted to draw the apparatus along in a horizontal
+direction after it has been raised to the desired
+altitude.</p>
+
+<p>The gyropters of the Davidson machine are 28
+feet in diameter, the entire structure being 67 feet
+long, and weighing 3 tons. It has been calculated
+that with the proposed pair of 50 horse-power engines
+the gyropters will lift 5 tons. Upon a trial with a
+10 horse-power motor connected to one of the gyropters,
+that end of the apparatus was lifted from the
+ground at 55 revolutions per minute&mdash;the boiler
+pressure being 800 lbs. to the square inch, at which
+pressure it burst, wrecking the machine.</p>
+
+<p>An example of the gyroplane is the French Breguet
+apparatus, a blend of the aeroplane and the helicopter.
+<span class="pagenum" id="Page_149">149</span>
+It combines the fixed wing-planes of the one
+with the revolving vanes of the other. The revolving
+surfaces have an area of 82 square feet, and the fixed
+surfaces 376 square feet. The total weight of machine
+and operator is about 1,350 lbs. Fitted with
+a 40 horse-power motor, it rose freely into the air.</p>
+
+<p>The ornithopter, or flapping-wing type of flying
+machine, though the object of experiment and research
+for years, must still be regarded as unsuccessful.
+The apparatus of M. de la Hault may be taken
+as typical of the best effort in that line, and it is yet
+in the experimental stage. The throbbing beat of the
+mechanism, in imitation of the bird’s wings, has
+always proved disastrous to the structure before sufficient
+power was developed to lift the apparatus.</p>
+
+<p>The most prominent exponent of the tetrahedral
+type&mdash;that made up of numbers of small cells set
+one upon another&mdash;is the <i>Cygnet</i> of Dr. Alexander
+Graham Bell, which perhaps is more a kite than a
+true flying machine. The first <i>Cygnet</i> had 3,000
+cells, and lifted its pilot to a height of 176 feet. The
+<i>Cygnet II</i>. has 5,000 tetrahedral cells, and is propelled
+by a 50 horse-power motor. It has yet to
+make its record.</p>
+
+<p>One of the most recently devised machines is that
+<span class="pagenum" id="Page_150">150</span>
+known as the Fritz Russ flyer. It has two wings,
+each in the form of half a cylinder, the convex curve
+upward. It is driven by two immense helical screws,
+or spirals, set within the semi-cylinders. No details
+of its performances are obtainable.
+<span class="pagenum" id="Page_151">151</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_VIII">Chapter VIII.<br />
+
+FLYING MACHINES: HOW TO OPERATE.</h2>
+
+<blockquote>
+
+<p>Instinctive balance&mdash;When the motor skips&mdash;Progressive experience&mdash;Plum
+Island School methods&mdash;Lilienthal’s conclusions&mdash;The
+Curtiss mechanism and controls&mdash;Speed records&mdash;Cross-country
+flying&mdash;Landing&mdash;Essential qualifications&mdash;Ground
+practice&mdash;Future relief.</p></blockquote>
+
+<p class="drop"><span class="uppercase">Any</span> one who has learned to ride a bicycle will
+recall the great difficulty at first experienced
+to preserve equilibrium. But once the knack was
+gained, how simple the matter seemed! Balancing
+became a second nature, which came into play instinctively,
+without conscious thought or effort. On
+smooth roads it was not even necessary to grasp the
+handle-bars. The swaying of the body was sufficient
+to guide the machine in the desired direction.</p>
+
+<p>Much of this experience is paralleled by that of
+the would-be aviator. First, he must acquire the art
+of balancing himself and his machine in the air
+without conscious effort. Unfortunately, this is even
+harder than in the case of the bicycle. The cases
+<span class="pagenum" id="Page_152">152</span>
+would be more nearly alike if the road beneath and
+ahead of the bicyclist were heaving and falling as in
+an earthquake, with no light to guide him; for the
+air currents on which the aviator must ride are in
+constant and irregular motion, and are as wholly invisible
+to him as would be the road at night to the
+rider of the wheel.</p>
+
+<p>And there are other things to distract the attention
+of the pilot of an aeroplane&mdash;notably the roar
+of the propeller, and the rush of wind in his face,
+comparable only to the ceaseless and breath-taking
+force of the hurricane.</p>
+
+<p>The well-known aviator, Charles K. Hamilton,
+says:&mdash;“So far as the air currents are concerned,
+I rely entirely on instinctive action; but my ear is
+always on the alert. The danger signal of the aviator
+is when he hears his motor miss an explosion.
+Then he knows that trouble is in store. Sometimes
+he can speed up his engine, just as an automobile
+driver does, and get it to renew its normal action.
+But if he fails in this, and the motor stops, he must
+dip his deflecting planes, and try to negotiate a landing
+in open country. Sometimes there is no preliminary
+warning from the motor that it is going to
+cease working. That is the time when the aviator
+<span class="pagenum" id="Page_153">153</span>
+must be prepared to act quickly. Unless the deflecting
+planes are manipulated instantly, aviator
+and aeroplane will rapidly land a tangled mass on
+the ground.”</p>
+
+<div class="figcenter">
+<img src="images/i_153.jpg" alt="" />
+<p class="caption">Result of a failure to deflect the planes quickly enough when the engine stopped.
+The operator fortunately escaped with but a few bruises.</p></div>
+
+<p>At the same time, Mr. Hamilton says: “Driving
+an aeroplane at a speed of 120 miles an hour is not
+nearly so difficult a task as driving an automobile
+60 miles an hour. In running an automobile at high
+speed the driver must be on the job every second.
+<span class="pagenum" id="Page_154">154</span>
+Nothing but untiring vigilance can protect him from
+danger. There are turns in the road, bad stretches
+of pavement, and other like difficulties, and he can
+never tell at what moment he is to encounter some
+vehicle, perhaps travelling in the opposite direction.
+But with an aeroplane it is a different proposition.
+Once a man becomes accustomed to aeroplaning, it
+is a matter of unconscious attention.... He has
+no obstacles to encounter except cross-currents of air.
+Air and wind are much quicker than a man can
+think and put his thought into action. Unless experience
+has taught the aviator to maintain his equilibrium
+instinctively, he is sure to come to grief.”</p>
+
+<p>The Wright brothers spent years in learning the
+art of balancing in the air before they appeared in
+public as aviators. And their method of teaching
+pupils is evidence that they believe the only road to
+successful aviation is through progressive experience,
+leading up from the use of gliders for short
+flights to the actual machines with motors only after
+one has become an instinctive equilibrist.</p>
+
+<p>At the Plum Island school of the Herring-Burgess
+Company the learner is compelled to begin at
+the beginning and work the thing out for himself.
+He is placed in a glider which rests on the ground.
+<span class="pagenum" id="Page_155">155</span>
+The glider is locked down by a catch which may be
+released by pulling a string. To the front end of the
+glider is attached a long elastic which may be
+stretched more or less, according to the pull desired.
+The beginner starts with the elastic stretched but a
+little. When all is ready he pulls the catch free, and
+is thrown forward for a few feet. As practice gains
+for him better control, he makes a longer flight; and
+when he can show a perfect mastery of his craft for
+<span class="pagenum" id="Page_156">156</span>
+a flight of 300 feet, and not till then, he is permitted
+to begin practice with a motor-driven machine.</p>
+
+<div class="figcenter">
+<img src="images/i_155.jpg" alt="" />
+<p class="caption">A French apparatus for instructing pupils in aviation.</p></div>
+
+<p>The lamented Otto Lilienthal, whose experience
+in more than 2,000 flights gives his instructions
+unquestionable weight, urges that the “gradual development
+of flight should begin with the simplest apparatus
+and movements, and without the complication
+of dynamic means. With simple wing surfaces
+... man can carry out limited flights ... by
+gliding through the air from elevated points in paths
+more or less descending. The peculiarities of wind
+effects can best be learned by such exercises....
+The maintenance of equilibrium in forward flight
+is a matter of practice, and can be learned only by
+repeated personal experiment.... Actual practice
+in individual flight presents the best prospects for
+developing our capacity until it leads to perfected
+free flight.”</p>
+
+<p>The essential importance of thorough preparation
+in the school of experience could scarcely be made
+plainer or stronger. If it seems that undue emphasis
+has been laid upon this point, the explanation
+must be found in the deplorable death record among
+aviators from accidents in the air. With few exceptions,
+the cause of accident has been reported as,
+<span class="pagenum" id="Page_157">157</span>
+“The aviator seemed to lose control of his machine.”
+If this is the case with professional flyers, the need
+for thorough preliminary training cannot be too
+strongly insisted upon.</p>
+
+<p>Having attained the art of balancing, the aviator
+has to learn the mechanism by which he may control
+his machine. While all of the principal machines
+are but different embodiments of the same principles,
+there is a diversity of design in the arrangement of
+the means of control. We shall describe that of the
+Curtiss biplane, as largely typical of them all.</p>
+
+<p>In general, the biplane consists of two large sustaining
+planes, one above the other. Between the
+planes is the motor which operates a propeller located
+in the rear of the planes. Projecting behind
+the planes, and held by a framework of bamboo rods,
+is a small horizontal plane, called the tail. The rudder
+which guides the aeroplane to the right or the
+left is partially bisected by the tail. This rudder
+is worked by wires which run to a steering wheel located
+in front of the pilot’s seat. This wheel is similar
+in size and appearance to the steering wheel of
+an automobile, and is used in the same way for
+guiding the aeroplane to the right or left. (See <a href="#Chapter_V">illustration
+of the Curtiss machine in Chapter V</a>.)
+<span class="pagenum" id="Page_158">158</span></p>
+
+<p>In front of the planes, supported on a shorter projecting
+framework, is the altitude rudder, a pair
+of planes hinged horizontally, so that their front
+edges may tip up or down. When they tilt up, the
+air through which the machine is passing catches on
+the under sides and lifts them up, thus elevating
+the front of the whole aeroplane and causing it
+to glide upward. The opposite action takes place
+when these altitude planes are tilted downward.
+This altitude rudder is controlled by a long rod
+which runs to the steering wheel. By pushing on the
+wheel the rod is shoved forward and turns the altitude
+planes upward. Pulling the wheel turns the
+rudder planes downward. This rod has a backward
+and forward thrust of over two feet, but the
+usual movement in ordinary wind currents is rarely
+more than an inch. In climbing to high levels or
+swooping down rapidly the extreme play of the rod
+is about four or five inches.</p>
+
+<p>Thus the steering wheel controls both the horizontal
+and vertical movements of the aeroplane. More
+than this, it is a feeler to the aviator, warning him
+of the condition of the air currents, and for this reason
+must not be grasped too firmly. It is to be held
+steady, yet loosely enough to transmit any wavering
+<span class="pagenum" id="Page_159">159</span>
+<span class="pagenum" id="Page_160">160</span>
+force in the air to the sensitive touch of the pilot,
+enabling him instinctively to rise or dip as the current
+compels.</p>
+
+<div class="figcenter">
+<img src="images/i_159.jpg" alt="" />
+<p class="small"><i>Courtesy N. Y. Times.</i></p>
+
+<blockquote>
+
+<p>View of the centre of the new Wright machine, showing method of operating. Archibald Hoxsey in the pilot’s
+seat. In his right hand he holds a lever with two handles, one operating the warping of the wing tips,
+and the other the rudder. Both handles may be grasped at once, operating both rudder and wing tips
+at the same moment. In his left hand Hoxsey grasps the lever operating the elevating plane&mdash;at the
+rear in this type. The passenger’s seat is shown at the pilot’s right.</p></blockquote>
+</div>
+
+<p>The preserving of an even keel is accomplished
+in the Curtiss machine by small planes hinged between
+the main planes at the outer ends. They
+serve to prevent the machine from tipping over sideways.
+They are operated by arms, projecting from
+the back of the aviator’s seat, which embrace his
+shoulders on each side, and are moved by the swaying
+of his body. In a measure, they are automatic
+in action, for when the aeroplane sags downward
+on one side, the pilot naturally leans the other way
+to preserve his balance, and that motion swings the
+ailerons (as these small stabilizing planes are called)
+in such a way that the pressure of the wind restores
+the aeroplane to an even keel. The wires which connect
+them with the back of the seat are so arranged
+that when one aileron is being pulled down at its
+rear edge the rear of the other one is being raised,
+thus doubling the effect. As the machine is righted
+the aviator comes back to an upright position, and
+the ailerons become level once more.</p>
+
+<div class="figcenter">
+<img src="images/i_161.jpg" alt="" />
+<p class="caption">Starting a Wright machine. When the word is given both assistants pull vigorously downward on the propeller blades.</p></div>
+
+<p>There are other controls which the pilot must
+operate consciously. In the Curtiss machine these
+<span class="pagenum" id="Page_161">161</span>
+<span class="pagenum" id="Page_162">162</span>
+are levers moved by the feet. With a pressure of the
+right foot he short-circuits the magneto, thus cutting
+off the spark in the engine cylinders and stopping
+the motor. This lever also puts a brake on the forward
+landing wheels, and checks the speed of the
+machine as it touches the ground. The right foot
+also controls the pump which forces the lubricating
+oil faster or slower to the points where it is needed.</p>
+
+<p>The left foot operates the lever which controls the
+throttle by which the aviator can regulate the flow
+of gas to the engine cylinders. The average speed
+of the 7-foot propeller is 1,100 revolutions per minute.
+With the throttle it may be cut down to 100
+revolutions per minute, which is not fast enough to
+keep afloat, but will help along when gliding.</p>
+
+<p>Obviously, travelling with the wind enables the
+aviator to make his best speed records, for the speed
+of the wind is added to that of his machine through
+the air. Again, since the wind is always slower near
+the ground, the aviator making a speed record will
+climb up to a level where the surface currents no
+longer affect his machine. But over hilly and wooded
+country the air is often flowing or rushing in conflicting
+channels, and the aviator does not know what
+he may be called upon to face from one moment to
+<span class="pagenum" id="Page_163">163</span>
+the next. If the aeroplane starts to drop, it is only
+necessary to push the steering wheel forward a little&mdash;perhaps
+half an inch&mdash;to bring it up again.
+Usually, the machine will drop on an even keel.
+Then, in addition to the motion just described, the
+aviator will lean toward the higher side, thus moving
+the ailerons by the seat-back, and at the same
+time he will turn the steering wheel toward the lower
+side. This movement of the seat-back is rarely
+more than 2 inches.</p>
+
+<div class="figcenter">
+<img src="images/i_163.jpg" alt="" />
+<blockquote>
+
+<p>Diagram showing action of wind on flight of aeroplane. The force and direction
+of the wind being represented by the line <i>A B</i>, and the propelling
+force and steered direction being <i>A C</i>, the actual path travelled will be <i>A D</i>.</p></blockquote>
+</div>
+
+<p>In flying across country a sharp lookout is kept
+on the land below. If it be of a character unfit for
+landing, as woods, or thickly settled towns, the aviator
+must keep high up in the air, lest his engine
+<span class="pagenum" id="Page_164">164</span>
+stop and he be compelled to glide to the earth. A
+machine will glide forward 3 feet for each foot that
+it drops, if skilfully handled. If he is up 200 feet,
+he will have to find a landing ground within 600
+feet. If he is up 500 feet, he may choose his alighting
+ground anywhere within 1,500 feet. Over a city
+like New York, a less altitude than 1,500 feet would
+hardly be safe, if a glide became necessary.</p>
+
+<p>Mr. Clifford B. Harmon, who was an aeronaut
+of distinction before he became an aviator, under the
+instruction of Paulhan, has this to say: “It is like
+riding a bicycle, or running an automobile. You
+have to try it alone to really learn how. When one
+first handles a flying machine it is advisable to keep
+on the ground, just rolling along. This is a harder
+mental trial than you will imagine. As soon as one
+is seated in a flying machine he wishes to fly. It is
+almost impossible to submit to staying near the earth.
+But until the manipulation of the levers and the
+steering gear has become second nature, this must be
+done. It is best to go very slow in the beginning.
+Skipping along the ground will teach a driver much.
+When one first gets up in the air it is necessary to
+keep far from all obstacles, like buildings, trees, or
+crowds. There is the same tendency to run into
+<span class="pagenum" id="Page_165">165</span>
+<span class="pagenum" id="Page_166">166</span>
+them that an amateur bicycle rider has in regard
+to stones and ruts on the ground. When he keeps
+his eye on them and tries with all his might to steer
+clear of them, he runs right into them.”</p>
+
+<div class="figcenter">
+<img src="images/i_165.jpg" alt="" />
+<p class="caption">Practicing with a monoplane, 20 feet above the ground.</p></div>
+
+<p>When asked what he regarded the fundamental
+requirements in an aviator, Mr. Harmon said:
+“First, he must be muscularly strong; so that he
+will not tire. Second, he should have a thorough
+understanding of the mechanism of the machine he
+drives. Third, mental poise&mdash;the ability to think
+quick and to act instantly upon your thought.
+Fourth, a feeling of confidence in the air, so that
+he will not feel strange or out of place. This familiarity
+with the air can be best obtained by first
+being a passenger in a balloon, then by controlling
+one alone, and lastly going up in a flying machine.”</p>
+
+<div class="figcenter">
+<img src="images/i_167.jpg" alt="" />
+<p class="caption">Grahame-White on his Bleriot No. XII. The lever in front of him operates
+all the controls through the movement of the drum at its base.</p></div>
+
+<p>Mr. Claude Grahame-White, the noted English
+aviator, has this to say of his first experience with
+his big “No. XII.” Bleriot monoplane&mdash;which differs
+in many important features from the “No.
+XI.” machine in which M. Bleriot crossed the English
+Channel: “After several disappointments, I
+eventually obtained the delivery of my machine in
+working order.... As I had gathered a good deal
+of information from watching the antics and profiting
+<span class="pagenum" id="Page_167">167</span>
+by the errors made by other beginners on Bleriot
+monoplanes, I had a good idea of what <i>not</i> to do
+when the engine was started up and we were ready
+for our first trial.... It was a cold morning, but
+the engine started up at the first quarter turn. After
+many warnings from M. Bleriot’s foreman not on
+any account to accelerate my engine too much, I
+mounted the machine along with my friend as passenger,
+and immediately gave the word to let go, and
+<span class="pagenum" id="Page_168">168</span>
+we were soon speeding along the ground at a good
+sixty kilometers (about 37 miles) per hour....
+Being very anxious to see whether the machine would
+lift off the ground, I gave a slight jerk to the elevating
+plane, and soon felt the machine rise into the
+air; but remembering the warnings of the foreman,
+and being anxious not to risk breaking the machine,
+I closed the throttle and contented myself with running
+around on the ground to familiarize myself with
+the handling of the machine.... The next day we
+got down to Issy about five o’clock in the morning,
+some two hours before the Bleriot mechanics turned
+up. However, we got the machine out, and tied it
+to some railings, and then I had my first experience
+of starting an engine, which to a novice at first sight
+appears a most hazardous undertaking; for unless
+the machine is either firmly held by several men, or
+is strongly tied up, it has a tendency to immediately
+leap forward. We successfully started the engine,
+and then rigged up a leash, and when we had
+mounted the machine, we let go; and before eight
+o’clock we had accomplished several very successful
+flights, both with and against the wind. These experiences
+we continued throughout the day, and by
+nightfall I felt quite capable of an extended flight,
+<span class="pagenum" id="Page_169">169</span>
+if only the ground had been large enough.... The
+following day M. Bleriot returned, and he sent for
+me and strongly urged me not to use the aeroplane
+any more at Issy, as he said the ground was far too
+small for such a powerful machine.”</p>
+
+<div class="figcenter">
+<img src="images/i_169.jpg" alt="" />
+<blockquote>
+
+<p>Diagram of Bleriot monoplane, showing controlling lever <i>L</i> and bell-shaped
+drum <i>C</i>, to which all controlling wires are attached. When the bell is
+rocked back and forward the elevator tips on the rear plane are moved;
+rocking from side to side moves the stabilizing tips of the main plane.
+Turning the bell around moves the rudder.</p></blockquote>
+</div>
+
+<p><span class="pagenum" id="Page_170">170</span></p>
+
+<table class="images">
+  <tr>
+    <td class="w50"><img src="images/i_170.jpg" alt="" /></td>
+    <td>The Marmonier gyroscopic pendulum,
+    devised to secure
+    automatic stability of aeroplanes.
+    The wheels are
+    driven by the aeroplane motor
+    at high speed. The pendulum
+    rod is extended upward
+    above the axis and
+    carries a vane which is engaged
+    by any gust of wind
+    from either side of the aeroplane,
+    tending to tilt the
+    pendulum, and bringing its
+    gyroscopic resistance into
+    play to warp the wings, or
+    operate ailerons.</td>
+  </tr></table>
+
+<p>The caution shown by these experienced aviators
+cannot be too closely followed by a novice. These
+men do not say that their assiduous practice on the
+ground was the fruit of timidity. On the contrary,
+although they are long past the preliminary stages,
+their advice to beginners is uniformly in the line of
+caution and thorough practice.
+<span class="pagenum" id="Page_171">171</span></p>
+
+<div class="figcenter">
+<img src="images/i_171.jpg" alt="" />
+<blockquote>
+
+<p>When the aeroplane is steered to the left, the pendulum swings to the right and
+depresses the right side of the plane, as in (<i>c</i>). The reaction of the air
+raises the right side of the plane until both surfaces are perpendicular
+to the inclined pendulum, as in (<i>d</i>).</p></blockquote>
+
+<p class="caption">Diagrams showing action of Marmonier gyroscopic pendulum.</p>
+</div>
+
+<p>Even after one has become an expert, the battle
+is not won, by any means. While flying in calm
+weather is extremely pleasurable, a protracted flight
+is very fatiguing; and when it is necessary to wrestle
+<span class="pagenum" id="Page_172">172</span>
+with gusts of high wind and fickle air currents, the
+strain upon the strongest nerve is a serious source
+of danger in that the aviator is liable to be suddenly
+overcome by weariness when he most needs to be
+on the alert.</p>
+
+<div class="figcenter">
+<img src="images/i_172.jpg" alt="" />
+<blockquote>
+
+<p>In that inclined position the aeroplane makes the turn, and when the course
+again becomes straight, both the gyroscopic and centrifugal forces cease,
+and the pendulum under the influence of gravity becomes vertical. In
+this position it is inclined to the left with respect to the planes, on which
+its effect is to depress the left wing and so right the aeroplane, as in (<i>e</i>).</p></blockquote>
+
+<p class="caption">Diagram showing action of Marmonier gyroscopic pendulum.</p></div>
+
+<p>Engine troubles are much fewer than they used
+to be, and a more dependable form of motor relieves
+the mind of the aviator from such mental disturbance.
+Some device in the line of a wind-shield
+would be a real boon, for even in the best weather
+there is the ceaseless rush of air into one’s face at
+45 to 50 miles an hour. The endurance of this for
+hours is of itself a tax upon the most vigorous
+physique.
+<span class="pagenum" id="Page_173">173</span></p>
+
+<p>With the passing of the present spectacular stage
+of the art of flying there will doubtless come a more
+reliable form of machine, with corresponding relief
+to the operator. Automatic mechanism will supplant
+the intense and continual mental attention now
+demanded; and as this demand decreases, the joys of
+flying will be considerably enhanced.</p>
+
+<div class="figcenter">
+<img src="images/i_173.jpg" alt="" />
+<blockquote>
+
+<p>If, when pursuing a straight course, the aeroplane is tilted by a sideways wind
+(<i>b</i>), the action of the pendulum as described above restores it to an even
+keel, as in (<i>a</i>).</p></blockquote>
+
+<p class="caption">Diagrams showing action of Marmonier gyroscopic pendulum.
+<span class="pagenum" id="Page_174">174</span></p>
+</div>
+
+<hr class="chap" />
+
+<h2 id="Chapter_IX">Chapter IX.<br />
+
+FLYING MACHINES: HOW TO BUILD.</h2>
+
+<blockquote>
+
+<p>Santos-Dumont’s gift&mdash;<i>La Demoiselle</i>&mdash;Mechanical skill required&mdash;Preparatory
+practice&mdash;General dimensions&mdash;The
+frame&mdash;The motor&mdash;The main planes&mdash;The rudder-tail&mdash;The
+propeller&mdash;Shaping the blades&mdash;Maxim’s experience&mdash;The
+running gear&mdash;The controls&mdash;Scrupulous workmanship.</p></blockquote>
+
+<p class="drop"><span class="uppercase">When</span> Santos-Dumont in 1909 gave to the
+world the unrestricted privilege of building
+monoplanes after the plans of his famous No. 20&mdash;afterward
+named <i>La Demoiselle</i>&mdash;he gave not only
+the best he knew, but as much as any one knows
+about the building of flying machines. Santos-Dumont
+has chosen the monoplane for himself because
+his long experience commends it above others,
+and <i>La Demoiselle</i> was the crowning achievement
+of years spent in the construction and operation of
+airships of all types. In view of Santos-Dumont’s
+notable successes in his chosen field of activity, no
+one will go astray in following his advice.
+<span class="pagenum" id="Page_175">175</span></p>
+
+<p>Of course, the possession of plans and specifications
+for an aeroplane does not make any man a
+skilled mechanic. It is well to understand at the
+start that a certain degree of mechanical ability is
+required in building a machine which will be entirely
+safe. Nor does the possession of a successful machine
+make one an aeronaut. As in the case of bicycling,
+there is no substitute for actual experience, while in
+the airship the art of balancing is of even greater
+importance than on the bicycle.</p>
+
+<p>The would-be aviator is therefore advised to put
+himself through a course of training of mind and
+body.</p>
+
+<p>Intelligent experimenting with some one of the
+models described in Chapter XI. will teach much of
+the action of aeroplanes in calms and when winds are
+blowing; and practice with an easily constructed
+glider (see <a href="#Chapter_XII">Chapter XII</a>.) will give experience in
+balancing which will be of the greatest value when
+one launches into the air for the first time with a
+power-driven machine. An expert acquaintance with
+gasoline motors and magnetos is a prime necessity.
+In short, every bit of information on the subject of
+flying machines and their operation cannot fail to be
+useful in some degree.
+<span class="pagenum" id="Page_176">176</span></p>
+
+<p>The dimensions of the various parts of the Santos-Dumont
+monoplane are given on the original
+plans according to the metric system. In reducing
+these to “long measure” inches, all measurements
+have been given to the nearest eighth of an inch.</p>
+
+<p>In general, we may note some of the peculiarities
+of <i>La Demoiselle</i>. The spread of the plane is
+18 feet from tip to tip, and it is 20 feet over all
+from bow to stern. In height, it is about 4 feet 2
+inches when the propeller blades are in a horizontal
+position. The total weight of the machine is 265
+lbs., of which the engine weighs about 66 lbs. The
+area of the plane is 115 square feet, so that the total
+weight supported by each square foot with Santos-Dumont
+(weighing 110 lbs.) on board is a trifle
+over 3 lbs.</p>
+
+<p>The frame of the body of the monoplane is largely
+of bamboo, the three main poles being 2 inches in
+diameter at the front, and tapering to about 1 inch
+at the rear. They are jointed with brass sockets
+just back of the plane, for convenience of taking
+apart for transportation. Two of these poles extend
+from the axle of the wheels backward and slightly
+upward to the rudder-post. The third extends from
+the middle of the plane between the wings, backward
+<span class="pagenum" id="Page_177">177</span>
+<span class="pagenum" id="Page_178">178</span>
+and downward to the rudder-post. In cross-section
+the three form a triangle with the apex at
+the top. These bamboo poles are braced about every
+2 feet with struts of steel tubing of oval section,
+and the panels so formed are tied by diagonals of
+piano wire fitted with turn-buckles to draw them
+taut.</p>
+
+<div class="figcenter">
+<img src="images/i_177.jpg" alt="" />
+<blockquote>
+
+<p>Side view of the Santos-Dumont monoplane. <i>MP</i>, main plane with radiator, <i>R</i>, hung underneath; <i>RP</i>, rudder plane worked by
+wires <i>HC</i>, attached to lever <i>L</i>; <i>VC</i>, vertical control wires; <i>WT</i>, tube through which run the warping wires worked by lever
+<i>K</i>, in a pocket of the pilot’s coat; <i>B</i>, <i>B</i>, bamboo poles of frame; <i>S</i>, <i>S</i>, brass, or aluminum sockets; <i>D</i>, <i>D</i>, struts of bicycle tubing;
+<i>G</i>, gasoline; <i>RG</i>, reserve gasoline; <i>M</i>, motor; <i>P</i>, propeller; <i>Q</i>, <i>Q</i>, outer rib of plane, showing camber; <i>N</i>, skid.</p></blockquote>
+</div>
+
+<p>In the Santos-Dumont machine a 2-cylinder,
+opposed Darracq motor of 30 horse-power was used.
+It is of the water-cooled type, the cooling radiator
+being a gridiron of very thin ⅛-inch copper tubing,
+and hung up on the under side of the plane on either
+side of the engine. The cylinders have a bore of
+about 4⅛ inches, and a stroke of about 4¾ inches.
+The propeller is 2-bladed, 6½ feet across, and is
+run at 1,400 revolutions per minute, at which speed
+it exerts a pull of 242 lbs.</p>
+
+<p>Each wing of the main plane is built upon 2
+transverse spars extending outward from the upper
+bamboo pole, starting at a slight angle upward and
+bending downward nearly to the horizontal as they
+approach the outer extremities. These spars are of
+ash, 2 inches wide, and tapering in thickness from
+1⅛ inches at the central bamboo to about ⅞ inch at
+the tips of the wings. They are bent into shape by
+<span class="pagenum" id="Page_179">179</span>
+<span class="pagenum" id="Page_180">180</span>
+immersion in hot water, and straining them around
+blocks nailed to the floor of the workshop, in the
+form shown at QQ, p. 177.</p>
+
+<div class="figcenter">
+<img src="images/i_179.jpg" alt="" />
+<blockquote>
+
+<p>Front view of the Santos-Dumont monoplane, showing position of tubular struts supporting the engine and the wings; also the
+guys, and warping wires entering the tubes inside the wheels. <i>MP</i>, the main plane; <i>TP</i>, tail plane in the rear; <i>R</i>, radiators;
+<i>M</i>, motor; <i>P</i>, propeller, the arrow showing direction of revolution.</p></blockquote>
+</div>
+
+<p>The front spar is set about 9 inches back from the
+front edge of the plane, and the rear one about 12
+inches forward of the back edge of the plane. Across
+these spars, and beneath them, running fore and aft,
+are bamboo rods about ¾ of an inch in diameter
+at the forward end, and tapering toward the rear.
+They are set 8½ inches apart (centre to centre), except
+at the tips of the wings. The two outer panels
+are 10¼ inches from centre to centre of the rods, to
+give greater elasticity in warping. These fore-and-aft
+rods are 6 feet 5 inches long, except directly
+back of the propeller, where they are 5 feet 8 inches
+long; they are bound to the spars with brass wire
+No. 25, at the intersections. They also are bent to
+a curved form, as shown in the plans, by the aid of
+the hot-water bath. Diagonal guys of piano wire are
+used to truss the frame in two panels in each wing.</p>
+
+<p>Around the outer free ends of the rods runs a
+piano wire No. 20, which is let into the tips of the
+rods in a slot ⅜ inch deep. To prevent the splitting
+of the bamboo, a turn or two of the brass wire may
+be made around the rod just back of the slot; but
+<span class="pagenum" id="Page_181">181</span>
+<span class="pagenum" id="Page_182">182</span>
+it is much better to provide thin brass caps for the
+ends of the rods, and to cut the slots in the metal
+as well as in the rods. Instead of caps, ferrules will
+do. When the slots are cut, let the tongue formed
+in the cutting be bent down across the bamboo to
+form the floor to the slot, upon which the piano wire
+may rest. The difference in weight and cost is very
+little, and the damage that may result from a split
+rod may be serious.</p>
+
+<div class="figcenter">
+<img src="images/i_181.jpg" alt="" />
+<p class="caption">Plan and details of construction of <i>La Demoiselle</i>.</p></div>
+
+<p>After the frame of the plane is completed it is
+to be covered with cloth on both sides, so as entirely
+to enclose the frame, except only the tips of the rods,
+as shown in the plans. In the Santos-Dumont monoplane
+the cloth used is of closely woven silk, but a
+strong, unbleached muslin will do&mdash;the kind made
+especially for aeroplanes is best.</p>
+
+<p>Both upper and lower surfaces must be stretched
+taut, the edges front and back being turned over the
+piano wire, and the wire hemmed in. The upper
+and lower surfaces are then sewed together&mdash;“through
+and through,” as a seamstress would say&mdash;along
+both sides of each rod, so that the rods are
+practically in “pockets.” Nothing must be slighted,
+if safety in flying is to be assured.</p>
+
+<div class="figcenter">
+<img src="images/i_183a.jpg" alt="" />
+<p class="caption">Sectional diagram of 2-cylinder Darracq opposed motor.</p></div>
+
+<div class="figcenter">
+<img src="images/i_183b.jpg" alt="" />
+<p class="caption">Diagram of 4-cylinder Darracq opposed motor.</p></div>
+
+<div class="figcenter">
+<img src="images/i_183c.jpg" alt="" />
+<p class="caption">Diagram of 3-cylinder Anzani motor.</p>
+
+<p class="caption">Motors suitable for <i>La Demoiselle</i> monoplane.</p></div>
+
+<p>The tail of the monoplane is a rigid combination
+<span class="pagenum" id="Page_183">183</span>
+<span class="pagenum" id="Page_184">184</span>
+of two planes intersecting each other at right angles
+along a central bamboo pole which extends back 3
+feet 5½ inches from the rudder-post, to which it is
+attached by a double joint, permitting it to move
+upon either the vertical or the horizontal axis.</p>
+
+<p>Although this tail, or rudder, may seem at first
+glance somewhat complicated in the plans, it will not
+be found so if the frame of the upright or vertical
+plane be first constructed, and that of the level or
+horizontal plane afterward built fast to it at right
+angles.</p>
+
+<p>As with the main plane, the tail is to be covered
+on both sides with cloth, the vertical part first; the
+horizontal halves on either side so covered that the
+cloth of the latter may be sewed above and below
+the central pole. All of the ribs in the tail are to be
+stitched in with “pockets,” as directed for the rods
+of the main plane.</p>
+
+<p>The construction of the motor is possible to an
+expert machinist only, and the aeroplane builder will
+save time and money by buying his engine from a
+reliable maker. It is not necessary to send to
+France for a Darracq motor. Any good gasoline
+engine of equal power, and about the same weight,
+will serve the purpose.
+<span class="pagenum" id="Page_185">185</span></p>
+
+<p>The making of the propeller is practicable for a
+careful workman. The illustrations will give a better
+idea than words of how it should be done. It
+should be remembered, however, that the safety of
+the aviator depends as much upon the propeller as
+upon any other part of the machine. The splitting
+of the blades when in motion has been the cause of
+serious accidents. The utmost care, therefore, should
+be exercised in the selection of the wood, and in the
+glueing of the several sections into one solid mass,
+allowing the work to dry thoroughly under heavy
+pressure.</p>
+
+<div class="figcenter">
+<img src="images/i_185.jpg" alt="" />
+<blockquote>
+
+<p>Diagram showing how the layers of wood are placed for glueing: <i>A</i>, at the hub;
+<i>B</i>, half way to the tip of the blade; <i>C</i>, at the tip. The dotted lines show
+the form of the blade at these points.</p></blockquote>
+</div>
+
+<p>The forming of the blades requires a good deal of
+skill, and some careful preliminary study. It is apparent
+<span class="pagenum" id="Page_186">186</span>
+that the speed of a point at the tip of a revolving
+blade is much greater than that of a point
+near the hub, for it traverses a larger circle in the
+same period of time. But if the propeller is to do
+effective work without unequal strain, the twist in the
+blade must be such that each point in the length of
+the blade is exerting an equal pull on the air. It
+is necessary, therefore, that the slower-moving part
+of the blade, near the hub, or axis, shall cut “deeper”
+into the air than the more swiftly moving tip of
+the blade. Consequently the blade becomes continually
+“flatter” (approaching the plane in which it
+revolves) as we work from the hub outward toward
+the tip. This “flattening” is well shown in the
+nearly finished blade clamped to the bench at the
+right of the illustration&mdash;which shows a four-bladed
+propeller, instead of the two-bladed type needed for
+the monoplane.</p>
+
+<p>The propeller used for propulsion in air differs
+from the propeller-wheel used for ships in water,
+in that the blades are curved laterally; the forward
+face of the blade being convex, and the rearward
+face concave. The object of this shaping is the same
+as for curving the surface of the plane&mdash;to secure
+smoother entry into the air forward, and a compression
+<span class="pagenum" id="Page_187">187</span>
+<span class="pagenum" id="Page_188">188</span>
+in the rear which adds to the holding power on
+the substance of the air. It is extremely difficult to
+describe this complex shape, and the amateur builder
+of a propeller will do well to inspect one made by a
+professional, or to buy it ready made with his engine.</p>
+
+<div class="figcenter">
+<img src="images/i_187.jpg" alt="" />
+<p class="caption">Forming a 4-blade propeller out of 8 layers of wood glued firmly together.</p></div>
+
+<p>The following quotation from Sir Hiram Maxim’s
+account of his most effective propeller may aid the
+ambitious aeroplane builder: “My large screws were
+made with a great degree of accuracy; they were perfectly
+smooth and even on both sides, the blades being
+thin and held in position by a strip of rigid wood
+on the back of the blade.... Like the small screws,
+they were made of the very best kind of seasoned
+American white pine, and when finished were varnished
+on both sides with hot glue. When this was
+thoroughly dry, they were sand-papered again, and
+made perfectly smooth and even. The blades were
+then covered with strong Irish linen fabric of the
+smoothest and best make. Glue was used for attaching
+the fabric, and when dry another coat of glue
+was applied, the surface rubbed down again, and
+then painted with zinc white in the ordinary way and
+varnished. These screws worked exceedingly well.”</p>
+
+<p>The covering of the blades with linen glued fast
+commends itself to the careful workman as affording
+<span class="pagenum" id="Page_189">189</span>
+precaution against the splintering of the blades
+when in rapid motion. Some propellers have their
+wooden blades encased with thin sheet aluminum to
+accomplish the same purpose, but for the amateur
+builder linen is far easier to apply.</p>
+
+<table class="images">
+  <tr>
+    <td><blockquote>
+
+    <p>This method of mounting the
+    wheels of the chassis has
+    been found the most satisfactory.
+    The spring takes
+    up the shock of a sudden
+    landing and the pivot working
+    in the hollow post allows
+    the entire mounting to swing
+    like a caster, and adapt itself
+    to any direction at which
+    the machine may strike the
+    ground.</p></blockquote></td>
+    <td class="w50"><img src="images/i_189.jpg" alt="" /></td>
+  </tr>
+</table>
+
+<p>The wheels are of the bicycle type, with wire
+spokes, but with hubs six inches long. The axle is
+bent to incline upward at the ends, so that the wheels
+incline outward at the ground, the better to take
+the shock of a sideways thrust when landing. The
+usual metal or wood rims may be used, but special
+<span class="pagenum" id="Page_190">190</span>
+tires of exceptionally light construction, made for
+aeroplanes, should be purchased.</p>
+
+<p>The controlling wires or cords for moving the rudder
+(or tail) and for warping the tips of the wings
+are of flexible wire cable, such as is made for use
+as steering rope on small boats. The cable controlling
+the horizontal plane of the rudder-tail is fastened
+to a lever at the right hand of the operator. The
+cable governing the vertical plane of the rudder-tail
+is attached to a wheel at the left hand of the operator.
+The cables which warp the tips of the wings
+are fastened to a lever which projects upward just
+back of the operator’s seat, and which is slipped
+into a long pocket sewed to the back of his coat, so
+that the swaying of his body in response to the fling
+of the tipping machine tends to restore it to an even
+keel. Springs are attached to all of these controlling
+wires, strong enough to bring them back to a normal
+position when the operator removes his hands from
+the steering apparatus.</p>
+
+<p>The brass sockets used in connecting the tubular
+struts to the main bamboos and the rudder-post, and
+in fastening the axle of the wheels to the lower bamboos
+and elsewhere, should be thoroughly made and
+brazed by a good mechanic, for no one should risk
+<span class="pagenum" id="Page_191">191</span>
+<span class="pagenum" id="Page_192">192</span>
+the chance of a faulty joint at a critical spot, when
+an accident may mean the loss of life.</p>
+
+<div class="figcenter">
+<img src="images/i_191.jpg" alt="" />
+<p class="caption">Diagram of Bleriot monoplane showing sizes of parts, in metres. Reduced to
+feet and inches these measurements are:</p>
+
+<table class="tdr">
+  <tr>
+    <td>0.60 metres</td>
+    <td>1 ft.</td>
+    <td>11½ in.</td>
+  </tr>
+  <tr>
+    <td>1.50 metres</td>
+    <td>4 ft.</td>
+    <td>11   in.</td>
+  </tr>
+  <tr>
+    <td>2.10 metres</td>
+    <td>6 ft.</td>
+    <td>10½ in.</td>
+  </tr>
+  <tr>
+    <td>3.50 metres</td>
+    <td>11 ft.</td>
+    <td> 6   in.</td>
+  </tr>
+  <tr>
+    <td>8.00 metres</td>
+    <td>26 ft.</td>
+    <td> 3   in.</td>
+  </tr>
+  <tr>
+    <td>8.60 metres</td>
+    <td>28 ft.</td>
+    <td> 2½    in.</td>
+  </tr>
+</table>
+
+<blockquote>
+
+<p>The diagram being drawn to scale other dimensions may be found. In both
+the plan (upper figure) and elevation (lower figure), <i>A</i>, <i>A</i>, is the main plane;
+<i>B</i>, tail plane; <i>C</i>, body; <i>D</i>, elevator wing-tips; <i>E</i>, rudder; <i>a</i>, <i>a</i>, rigid spar;
+<i>b</i>, <i>b</i>, flexible spar; <i>r</i>, <i>r</i>, points of attachment for warping-wires; <i>h</i>, <i>h</i>, guys;
+<i>H</i>, propeller; <i>M</i>, motor; <i>R</i>, radiator; <i>S</i>, pilot’s seat; <i>P</i>, chassis.</p></blockquote>
+</div>
+
+<p>For the rest, it has seemed better to put the details
+of construction on the plans themselves, where they
+will be available to the aeroplane builder without the
+trouble of continually consulting the text.</p>
+
+<p>Some of the work on an aeroplane will be found
+simple and easy; some of it, difficult and requiring
+much patience; and some impracticable to any one
+but a trained mechanic. But in all of it, the worker’s
+motto should be, “Fidelity in every detail.”
+<span class="pagenum" id="Page_193">193</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_X">Chapter X.<br />
+
+FLYING MACHINES: MOTORS.</h2>
+
+<blockquote>
+
+<p>Early use of steam&mdash;Reliability necessary&mdash;The gasoline motor&mdash;Carburetion&mdash;Compression&mdash;Ignition&mdash;Air-cooling&mdash;Water-cooling&mdash;Lubrication&mdash;The
+magneto&mdash;Weight&mdash;Types of
+motors&mdash;The propeller&mdash;Form, size, and pitch&mdash;Slip&mdash;Materials&mdash;Construction.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> possibility of the existence of the flying
+machine as we have it to-day has been ascribed
+to the invention of the gasoline motor. While this
+is not to be denied, it is also true that the gasoline
+motors designed and built for automobiles and motor-boats
+have had to be wellnigh revolutionized to make
+them suitable for use in the various forms of aircraft.
+And it is to be remembered, doubtless to their
+greater credit, that Henson, Hargrave, Langley, and
+Maxim had all succeeded in adapting steam to the
+problem of the flight of models, the two latter using
+gasoline to produce the steam.</p>
+
+<p>Perhaps the one predominant qualification demanded
+<span class="pagenum" id="Page_194">194</span>
+of the aeroplane motor is reliability. A
+motor-car or motor-boat can be stopped, and engine
+troubles attended to with comparatively little inconvenience.
+The aeroplane simply cannot stop without
+peril. It is possible for a skilful pilot to reach the
+earth when his engine stops, if he is fortunately high
+enough to have space for the downward glide which
+will gain for him the necessary headway for steering.
+At a lesser height he is sure to crash to the earth.</p>
+
+<p>An understanding of the principles on which the
+gasoline motor works is essential to a fair estimate
+of the comparative advantages of the different types
+used to propel aeroplanes. In the first place, the radical
+difference between the gasoline motor and other
+engines is the method of using the fuel. It is not
+burned in ordinary fashion, but the gasoline is first
+vaporized and mixed with a certain proportion of air,
+in a contrivance called a carburetor. This gaseous
+mixture is pumped into the cylinder of the motor
+by the action of the motor itself, compressed into
+about one-tenth of its normal volume, and then exploded
+by a strong electric spark at just the right
+moment to have its force act most advantageously to
+drive the machinery onward.</p>
+
+<div class="figcenter">
+<img src="images/i_195.jpg" alt="" />
+<p class="caption">The “Fiat” 8-cylinder air-cooled motor, of the “V” type, made in France.</p></div>
+
+<p>It is apparent that there are several chances for
+<span class="pagenum" id="Page_195">195</span>
+failure in this series. The carburetor may not do
+its part accurately. The mixture of air and vapor
+may not be in such proportions that it will explode;
+in that case, the power from that stroke will be missing,
+and the engine will falter and slow down. Or
+a leakage in the cylinder may prevent the proper
+compression of the mixture, the force from the explosion
+will be greatly reduced, with a corresponding
+loss of power and speed. Or the electric spark may
+not be “fat” enough&mdash;that is, of sufficient volume
+and heat to fire the mixture; or it may not “spark”
+at just the right moment; if too soon, it will exert
+<span class="pagenum" id="Page_196">196</span>
+its force against the onward motion: if too late, it
+will not deliver the full power of the explosion at the
+time when its force is most useful. The necessity
+for absolute perfection in these operations is obvious.</p>
+
+<div class="figcenter">
+<img src="images/i_196.jpg" alt="" />
+<p class="caption">A near view of the Holmes engine from the driving side.</p></div>
+
+<div class="figcenter">
+<img src="images/i_197.jpg" alt="" />
+<p class="caption">The Holmes rotative engine, 7-cylinder 35 horse-power, weighing 160 pounds.<br />
+An American engine built in Chicago, Ill.</p></div>
+
+<p>Other peculiarities of the gasoline motor affect
+considerably its use for aeroplanes. The continual
+and oft-repeated explosions of the gaseous mixture
+inside of the cylinder generate great heat, and this
+not only interferes with its regularity of movement,
+<span class="pagenum" id="Page_197">197</span>
+<span class="pagenum" id="Page_198">198</span>
+but within a very brief time checks it altogether.
+To keep the cylinder cool enough to be serviceable,
+two methods are in use: the air-cooling system and
+the water-cooling system. In the first, flanges of
+very thin metal are cast on the outside of the cylinder
+wall. These flanges take up the intense heat,
+and being spread out over a large surface in this
+way, the rushing of the air through them as the machine
+flies (or sometimes blown through them with
+a rotary fan) cools them to some degree. With the
+water-cooling system, the cylinder has an external
+jacket, the space between being filled with water
+which is made to circulate constantly by a small
+<span class="pagenum" id="Page_199">199</span>
+pump. In its course the water which has just taken
+up the heat from the cylinder travels through a radiator
+in which it is spread out very thin, and this
+radiator is so placed in the machine that it receives
+the full draught from the air rushing through the
+machine as it flies. The amount of water required
+for cooling a motor is about 1⅕ lbs. per horse-power.
+With an 8-cylinder 50 horse-power motor, this water
+<span class="pagenum" id="Page_200">200</span>
+would add the very considerable item of 60 lbs. to the
+weight the machine has to carry. As noted in a previous
+chapter, the McCurdy biplane has its radiator
+formed into a sustaining plane, and supports its own
+weight when travelling in the air.</p>
+
+<div class="figcenter">
+<img src="images/i_198.jpg" alt="" />
+<p class="caption">The 180 horse-power engine of Sir Hiram Maxim; of the “opposed” type,
+compound, and driven by steam.</p></div>
+
+<div class="figcenter">
+<img src="images/i_199.jpg" alt="" />
+<blockquote>
+
+<p>The Anzani motor and propeller which carried M. Bleriot across the English
+Channel. The curved edge of the propeller blades is the entering edge,
+the propeller turning from the right of the picture over to the left. The
+Anzani is of the “radiant” type and is of French build.</p></blockquote>
+</div>
+
+<p>It is an unsettled point with manufacturers
+whether the greater efficiency (generally acknowledged)
+of the water-cooled engine more than compensates
+for the extra weight of the water.</p>
+
+<p>Another feature peculiar to the gasoline motor is
+the necessity for such continual oiling that it is styled
+“lubrication,” and various devices have been invented
+to do the work automatically, without attention
+from the pilot further than the watching of his
+oil-gauge to see that a full flow of oil is being pumped
+through the oiling system.</p>
+
+<p>The electric current which produces the spark
+inside of the cylinder is supplied by a magneto, a
+machine formed of permanent magnets of horseshoe
+form, between the poles of which a magnetized armature
+is made to revolve rapidly by the machinery
+which turns the propeller. This magneto is often
+connected with a small storage battery, or accumulator,
+which stores up a certain amount of current for
+use when starting, or in case the magneto gives out.
+<span class="pagenum" id="Page_201">201</span></p>
+
+<div class="figcenter">
+<img src="images/i_201.jpg" alt="" />
+<blockquote>
+
+<p>Sectional drawings showing details of construction of the Anzani motor. The flanges of the air-cooling system are distinctly shown. The
+section at the left is from the side; that at the right, from the front. All measurements are in millimètres. A millimètre is 0.039 inch.
+<span class="pagenum" id="Page_202">202</span></p></blockquote></div>
+
+<p>The great rivalry of the builders of motors has
+been in cutting down the weight per horse-power to
+the lowest possible figure. It goes without saying
+that useless weight is a disadvantage in an aeroplane,
+but it has not been proven that the very lightest engines
+have made a better showing than those of sturdier
+build.</p>
+
+<div class="figcenter">
+<img src="images/i_202.jpg" alt="" />
+<p class="caption">The “Gobron” engine of the “double opposed,” or cross-shaped type.
+A water-cooled engine, with 8 cylinders.</p></div>
+
+<p>One of the items in the weight of an engine has
+been the fly-wheel found necessary on all motors of
+4 cylinders or less to give steadiness to the running.
+<span class="pagenum" id="Page_203">203</span>
+With a larger number of cylinders, and a consequently
+larger number of impulses in the circuit of
+the propeller, the vibration is so reduced that the
+fly-wheel has been dispensed with.</p>
+
+<div class="figcenter">
+<img src="images/i_203.jpg" alt="" />
+<p class="caption">The Emerson 6-cylinder aviation engine, of the “tandem” type, water-cooled;
+60 horse-power; made at Alexandria, Va.</p></div>
+
+<p>There are several distinct types of aircraft engines,
+based on the arrangement of the cylinders.
+The “tandem” type has the cylinders standing upright
+in a row, one behind another. There may be
+as many as eight in a row. The Curtiss and Wright
+engines are examples. Another type is the “opposed”
+arrangement, the cylinders being placed in a
+<span class="pagenum" id="Page_204">204</span>
+<span class="pagenum" id="Page_205">205</span>
+horizontal position and in two sets, one working opposite
+the other. An example of this type is seen in
+the Darracq motor used on the Santos-Dumont monoplane.
+Another type is the “V” arrangement, the
+cylinders set alternately leaning to right and to left,
+as seen in the “Fiat” engine. Still another type
+is the “radiant,” in which the cylinders are all above
+the horizontal, and disposed like rays from the rising
+sun. The 3-cylinder Anzani engine and the 5- and
+7-cylinder R-E-P engines are examples. The “star”
+type is exemplified in the 5 and 7-cylinder engines
+in which the cylinders radiate at equal angles
+all around the circle. The “double opposed” or
+cross-shaped type is shown in the “Gobron” engine.
+In all of these types the cylinders are stationary,
+and turn the propeller shaft either by cranks or by
+gearing.</p>
+
+<div class="figcenter">
+<img src="images/i_204.jpg" alt="" />
+<p class="caption">The Elbridge engine, of the “tandem” type and water-cooled. It is an American engine, built
+at Rochester, N. Y.</p></div>
+
+<p>An entirely distinct type of engine, and one which
+has been devised solely for the aeroplane, is the rotative&mdash;often
+miscalled the rotary, which is totally
+different. The rotative type may be illustrated by
+the Gnome motor. In this engine the seven cylinders
+turn around the shaft, which is stationary. The
+propeller is fastened to the cylinders, and revolves
+with them. This ingenious effect is produced by an
+<span class="pagenum" id="Page_206">206</span>
+<span class="pagenum" id="Page_207">207</span>
+<span class="pagenum" id="Page_208">208</span>
+offset of the crank-shaft of half the stroke of the pistons,
+whose rods are all connected with the crank-shaft.
+The entire system revolves around the main
+shaft as a centre, the crank-shaft being also stationary.</p>
+
+<div class="figcenter">
+<img src="images/i_206.jpg" alt="" />
+<blockquote>
+
+<p>The famous Gnome motor; 50 horse-power, 7-cylinder, air-cooled; of the
+rotative type; made in France. This illustration shows the Gnome steel
+propeller.</p></blockquote>
+</div>
+
+<div class="figcenter">
+<img src="images/i_207a.jpg" alt="" />
+<p class="caption">Sectional diagram of the 5-cylinder R-E-P motor; of the “radiant” type.</p></div>
+
+<div class="figcenter">
+<img src="images/i_207b.jpg" alt="" />
+<p class="caption">Sectional diagram of the 5-cylinder Bayard-Clement motor; of the “star”
+type.</p></div>
+
+<p>Strictly speaking, the propeller is not a part of the
+motor of the flying machine, but it is so intimately
+connected with it in the utilization of the power created
+by the motor, that it will be treated of briefly
+in this chapter.</p>
+
+<p>The form of the air-propeller has passed through
+a long and varied development, starting with that of
+the marine propeller, which was found to be very inefficient
+in so loose a medium as air. On account of
+this lack of density in the air, it was found necessary
+to act on large masses of it at practically the same
+time to gain the thrust needed to propel the aeroplane
+swiftly, and this led to increasing the diameter
+of the propeller to secure action on a proportionally
+larger area of air. The principle involved is simply
+the geometric rule that the areas of circles are to
+each other as the squares of their radii. Thus the
+surface of air acted on by two propellers, one of 6
+feet diameter and the other of 8 feet diameter, would
+be in the proportion of 9 to 16; and as the central
+<span class="pagenum" id="Page_209">209</span>
+<span class="pagenum" id="Page_210">210</span>
+part of a propeller has practically no thrust effect,
+the efficiency of the 8-foot propeller is nearly twice
+that of the 6-foot propeller&mdash;other factors being
+equal. But these other factors may be made to vary
+widely. For instance, the number of revolutions
+may be increased for the smaller propeller, thus engaging
+more air than the larger one at a lower speed;
+and, in practice, it is possible to run a small propeller
+at a speed that would not be safe for a large
+one. Another factor is the pitch of the propeller,
+which may be described as the distance the hub of
+the propeller would advance in one complete revolution
+if the blades moved in an unyielding medium, as
+a section of the thread of an ordinary bolt moves in
+its nut. In the yielding mass of the air the propeller
+advances only a part of its pitch, in some cases not
+more than half. The difference between the theoretical
+advance and the actual advance is called the
+“slip.”</p>
+
+<div class="figcenter">
+<img src="images/i_209.jpg" alt="" />
+<blockquote>
+
+<p>The Call Aviation Engine, of the opposed type; water-cooled. The cylinders are large and
+few in number. The 100 horse-power engine has but 4 cylinders, and weighs only
+250 pounds. (The Gnome 100 horse-power engine has 14 cylinders.) This is an
+American engine, built at Girard, Kansas.</p></blockquote>
+</div>
+
+<p>In practical work the number of blades which have
+been found to be most effective is two. More blades
+than two seem to so disturb the air that there is no
+hold for the propeller. In the case of slowly revolving
+propellers, as in most airship mechanisms, four-bladed
+propellers are used with good effect. But
+<span class="pagenum" id="Page_211">211</span>
+where the diameter of the propeller is about 8 feet,
+and the number of revolutions about 1,200 per minute,
+the two-bladed type is used almost exclusively.</p>
+
+<p>The many differing forms of the blades of the
+propeller is evidence that the manufacturers have not
+decided upon any definite shape as being the best.
+Some have straight edges nearly or quite parallel;
+others have the entering edge straight and the rear
+edge curved; in others the entering edge is curved,
+and the rear edge straight; or both edges may be
+curved. The majority of the wooden propellers are
+of the third-mentioned type, and the curve is fashioned
+so that at each section of its length the blade
+presents the same area of surface in the same time.
+Hence the outer tip, travelling the fastest, is narrower
+than the middle of the blade, and it is also
+much thinner to lessen the centrifugal force acting
+upon it at great speeds. Near the hub, however,
+where the travel is slowest, the constructional problem
+demands that the blade contract in width and
+be made stout. In fact, it becomes almost round in
+section.</p>
+
+<p>Many propellers are made of metal, with tubular
+shanks and blades of sheet metal, the latter either
+solid sheets or formed with a double surface and hollow
+<span class="pagenum" id="Page_212">212</span>
+inside. Still others have a frame of metal with
+blades of fabric put on loosely, so that it may adapt
+itself to the pressure of the air in revolving. That
+great strength is requisite becomes plain when it is
+considered that the speed of the tip of a propeller
+blade often reaches seven miles a minute! And at
+this velocity the centrifugal force excited&mdash;tending to
+tear the blades to splinters&mdash;is prodigious.</p>
+
+<p>Just as the curved surface of the planes of an
+aeroplane is more effective than a flat surface in
+compressing the air beneath them, and thus securing
+a firmer medium on which to glide, so the propeller
+blades are curved laterally (across their width) to
+compress the air behind them and thus secure a better
+hold. The advancing side of the blade is formed
+with a still greater curve, to gain the advantage due
+to the unexplained lift of the paradox aeroplane.</p>
+
+<p>Where the propeller is built of wood it is made of
+several layers, usually of different kinds of wood,
+with the grain running in slightly different directions,
+and all carefully glued together into a solid
+block. Ash, spruce, and mahogany, in alternating
+layers, are a favorite combination. In some instances
+the wooden propeller is sheathed in sheet
+aluminum; in others, it is well coated with glue
+<span class="pagenum" id="Page_213">213</span>
+<span class="pagenum" id="Page_214">214</span>
+which is sandpapered down very smooth, then varnished,
+and then polished to the highest lustre&mdash;to
+reduce the effect of the viscosity of the air to the
+minimum.</p>
+
+<div class="figcenter">
+<img src="images/i_213.jpg" alt="" />
+<blockquote>
+
+<p>Two propellers, the one on the left of left-hand pitch; the other of right-hand
+pitch. Both are thrusting propellers, and are viewed from the rear.
+These fine models are of the laminated type, and are of American make;
+the one to the left a Paragon propeller made in Washington, D. C.; the
+other a Brauner propeller made in New York.</p></blockquote>
+</div>
+
+<p>In order to get the best results, the propeller and
+the motor must be suited to each other. Some motors
+which “race” with a propeller which is slightly
+too small, work admirably with one a little heavier,
+or with a longer diameter.</p>
+
+<p>The question as to whether one propeller, or two,
+is the better practice, has not been decided. The
+majority of aeroplanes have but one. The Wright
+and the Cody machines have two. The certainty of
+serious consequences to a machine having two,
+should one of them be disabled, or even broken so
+as to reduce the area, seems to favor the use of but
+one.
+<span class="pagenum" id="Page_215">215</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XI">Chapter XI.<br />
+
+MODEL FLYING MACHINES.</h2>
+
+<blockquote>
+
+<p>Awakened popular interest&mdash;The workshop’s share&mdash;Needed devices&mdash;Super-sensitive
+inventions&mdash;Unsolved problems&mdash;Tools
+and materials&mdash;A model biplane&mdash;The propeller&mdash;The
+body&mdash;The steering plane&mdash;The main planes&mdash;Assembling
+the parts&mdash;The motive power&mdash;Flying the model&mdash;A monoplane
+model&mdash;Carving a propeller&mdash;Many ideas illustrated&mdash;Clubs
+and competitions&mdash;Some remarkable records.</p></blockquote>
+
+<p class="drop"><span class="uppercase">It</span> is related of Benjamin Franklin that when he
+went out with his famous kite with the wire
+string, trying to collect electricity from the thundercloud,
+he took a boy along to forestall the ridicule that
+he knew would be meted out to him if he openly flew
+the kite himself.</p>
+
+<p>Other scientific experimenters, notably those working
+upon the problem of human flight in our own
+time, have encountered a similar condition of the
+public mind, and have chosen to conduct their trials
+in secret rather than to contend with the derision,
+criticism, and loss of reputation which a sceptical
+world would have been quick to heap upon them.
+<span class="pagenum" id="Page_216">216</span></p>
+
+<p>But such a complete revolution of thought has been
+experienced in these latter days that groups of notable
+scientific men gravely flying kites, or experimenting
+with carefully made models of flying machines,
+arouse only the deepest interest, and their
+smallest discoveries are eagerly seized upon by the
+daily press as news of the first importance.</p>
+
+<p>So much remains to be learned in the field of
+aeronautics that no builder and flyer of the little
+model aeroplanes can fail to gain valuable information,
+if that is his intention. On the other hand,
+if it be the sport of racing these model aeroplanes
+which appeals to him, the instruction given in the
+pages following will be equally useful.</p>
+
+<p>The earnest student of aviation is reminded that
+the progressive work in this new art of flying is
+not being done altogether, nor even in large part,
+by the daring operators who, with superb courage, are
+performing such remarkable feats with the flying machines
+of the present moment. Not one of them
+would claim that his machine is all that could be desired.
+On the contrary, these intrepid men more
+than any others are fully aware of the many and
+serious defects of the apparatus they use for lack of
+better. The scientific student in his workshop, patiently
+<span class="pagenum" id="Page_217">217</span>
+<span class="pagenum" id="Page_218">218</span>
+experimenting with his models, and working
+to prove or disprove untested theories, is doubtless
+doing an invaluable part in bringing about the sort
+of flying which will be more truly profitable to humanity
+in general, though less spectacular.</p>
+
+<div class="figcenter">
+<img src="images/i_217.jpg" alt="" />
+<p class="caption">A model flying machine built and flown by Louis Paulhan, the noted aviator, at a prize contest for models in France.
+The design is after Langley’s model, with tandem monoplane surfaces placed at a dihedral angle.</p></div>
+
+<p>One of the greatest needs of the present machines
+is an automatic balancer which shall supersede the
+concentrated attention which the operator is now
+compelled to exercise in order to keep his machine
+right side up. The discovery of the principle upon
+which such a balancer must be built is undoubtedly
+within the reach of the builder and flyer of models.
+It has been asserted by an eminent scientific experimenter
+in things aeronautic that “we cannot hope
+to make a sensitive apparatus quick enough to take
+advantage of the rising currents of the air,” etc.
+With due respect to the publicly expressed opinion
+of this investigator, it is well to reassure ourselves
+against so pessimistic an outlook by remembering
+that the construction of just such supersensitive
+apparatus is a task to which man has frequently
+applied his intellectual powers with signal success.
+Witness the photomicroscope, which records faithfully
+an enlarged view of objects too minute to be
+even visible to the human eye; the aneroid barometer,
+<span class="pagenum" id="Page_219">219</span>
+so sensitive that it will indicate the difference in
+level between the table and the floor; the thermostat,
+which regulates the temperature of the water flowing
+in the domestic heating system with a delicacy impossible
+to the most highly constituted human organism;
+the seismograph, detecting, recording, and
+almost locating earth tremors originating thousands
+of miles away; the automatic fire sprinkler; the
+safety-valve; the recording thermometer and other
+meteorological instruments; and last, if not of least
+importance, the common alarm-clock. And these are
+but a few of the contrivances with which man does
+by blind mechanism that which is impossible to his
+sentient determination.</p>
+
+<p>Even if the nervous system could be schooled into
+<span class="pagenum" id="Page_220">220</span>
+endurance of the wear and tear of consciously balancing
+an aeroplane for many hours, it is still imperative
+that the task be not left to the exertion of
+human wits, but controlled by self-acting devices
+responding instantly to unforeseen conditions as they
+occur.</p>
+
+<div class="figcenter">
+<img src="images/i_219.jpg" alt="" />
+<p class="caption">Diagram showing turbulent air currents produced when a flat plane is forced
+through the air at a large angle of incidence in the direction A-B.</p></div>
+
+<div class="figcenter">
+<img src="images/i_220.jpg" alt="" />
+<p class="caption">Diagram showing smoothly flowing air currents caused by correctly shaped
+plane at proper angle of incidence.</p></div>
+
+<p>Some of the problems of which the model-builder
+may find the solution are: whether large screws revolving
+slowly, or small screws revolving rapidly,
+are the more effective; how many blades a propeller
+should have, and their most effective shape; what is
+the “perfect” material for the planes (Maxim found
+that with a smooth wooden plane he could lift 2½
+times the weight that could be lifted with the best
+made fabric-covered plane); whether the centre of
+<span class="pagenum" id="Page_221">221</span>
+gravity of the aeroplane should be above or below
+the centre of lift, or should coincide with it; new
+formulas for the correct expression of the lift in
+terms of the velocity, and angle of inclination&mdash;the
+former formulas having been proved erroneous by
+actual experience; how to take the best advantage of
+the “tangential force” announced by Lilienthal, and
+reasserted by Hargrave; and many others. And
+there is always the “paradox aeroplane” to be explained&mdash;and
+when explained it will be no longer a
+paradox, but will doubtless open the way to the most
+surprising advance in the art of flying.</p>
+
+<p>It is not assumed that every reader of this chapter
+will become a studious experimenter, but it is unquestionably
+true that every model-builder, in his
+effort to produce winning machines, will be more
+than likely to discover some fact of value in the
+progress making toward the ultimate establishment
+of the commercial navigation of the air.</p>
+
+<p>The tools and materials requisite for the building
+of model aeroplanes are few and inexpensive. For
+the tools&mdash;a small hammer; a small iron “block”
+plane; a fine-cut half-round file; a pair of round-nose
+pliers; three twist drills (as used for drilling metals),
+the largest 1/16 inch diameter, and two smaller sizes,
+<span class="pagenum" id="Page_222">222</span>
+with an adjustable brad-awl handle to hold them;
+a sharp pocket knife; and, if practicable, a small
+hand vise. The vise may be dispensed with, and
+common brad-awls may take the place of the drills,
+if necessary.</p>
+
+<p>For the first-described model&mdash;the simplest&mdash;the
+following materials are needed: some thin whitewood,
+1/16 inch thick (as prepared for fret-sawing);
+some spruce sticks, ¼ inch square (sky-rocket sticks
+are good); a sheet of heavy glazed paper; a bottle of
+liquid glue; some of the smallest (in diameter) brass
+screws, ¼ to ½ inch long; some brass wire, 1/20 inch in
+diameter; 100 inches of square rubber (elastic)
+“cord,” such as is used on return-balls, but 1/16 inch
+square; and a few strips of draughtsman’s tracing
+cloth.</p>
+
+<div class="figcenter">
+<img src="images/i_223.jpg" alt="" />
+<blockquote>
+
+<p><i>A</i>, <i>B</i>, blank from which propeller
+is shaped; <i>P</i>, <i>P</i>, pencil lines at
+centre of bend; <i>C</i>, <i>D</i>, sections of
+blade at points opposite; <i>E</i>, <i>G</i>, propeller
+after twisting; <i>H</i>, view of
+propeller endwise, showing outward
+twist of tips; also shaft.</p></blockquote>
+</div>
+
+<p>As the propeller is the most difficult part to make,
+it is best to begin with it. The flat blank is cut out
+of the whitewood, and subjected to the action of
+steam issuing from the spout of an actively boiling
+tea-kettle. The steam must be hot; mere vapor will
+not do the work. When the strip has become pliable,
+the shaping is done by slowly bending and twisting
+at the same time&mdash;perhaps “coaxing” would be the
+better word, for it must be done gently and with
+<span class="pagenum" id="Page_223">223</span>
+<span class="pagenum" id="Page_224">224</span>
+patience&mdash;and the steam must be playing on the wood
+all the time, first on one side of the strip, then on
+the other, at the point where the fibres are being bent.
+The utmost care should be taken to have the two
+blades bent exactly alike&mdash;although, of course, with
+a contrary twist, the one to the right and the other to
+the left, on each side of the centre. A lead-pencil
+line across each blade at exactly the same distance
+from the centre will serve to fix accurately the centre
+of the bend. If two blocks are made with slots cut
+at the angle of 1 inch rise to 2¼ inches base, and
+nailed to the top of the work bench just far enough
+apart to allow the tips of the screw to be slid into the
+slots, the drying in perfect shape will be facilitated.
+The centre may be held to a true upright by two other
+blocks, one on each side of the centre. Some strips
+of whitewood may be so rigid that the steam will not
+make them sufficiently supple. In this case it may be
+necessary to dip them bodily into the boiling water,
+or even to leave them immersed for a few minutes;
+afterward bending them in the hot steam. But a
+wetted stick requires longer to dry and set in the screw
+shape. When the propeller is thoroughly dry and set
+in proper form, it should be worked into the finished
+shape with the half-round file, according to the several
+<span class="pagenum" id="Page_225">225</span>
+sections shown beside the elevation for each part
+of the blade. The two strengthening piece’s are then
+to be glued on at the centre of the screw, and when
+thoroughly dry, worked down smoothly to shape.
+When all is dry and hard it should be smoothed with
+the finest emery cloth and given a coat of shellac varnish,
+which, in turn, may be rubbed to a polish with
+rotten stone and oil.</p>
+
+<p>It may be remarked, in passing, that this is a crude
+method of making a propeller, and the result cannot
+be very good. It is given here because it is the easiest
+way, and the propeller will work. A much better
+way is described further on&mdash;and the better the propeller,
+the better any model will fly. But for a novice,
+no time will be lost in making this one, for the
+experience gained will enable the model-builder to
+do better work with the second one than he could do
+without it.</p>
+
+<p>For the aeroplane body we get out a straight spar
+of spruce, ¼ inch square and 15½ inches long. At the
+front end of this&mdash;on the upper side&mdash;is to be glued
+a small triangular piece of wood to serve as a support
+for the forward or steering plane, tilting it up
+at the front edge at the angle represented by a rise
+of 1 in 8. This block should be shaped on its upper
+<span class="pagenum" id="Page_226">226</span>
+side to fit the curve of the under side of the steering-plane,
+which will be screwed to it.</p>
+
+<p>The steering-plane is cut according to plan, out
+of 1/16 inch whitewood, planed down gradually to be
+at the ends about half that thickness. This plane is
+to be steamed and bent to a curve (fore and aft) as
+shown in the sectional view. The steam should play
+on the <i>convex</i> side of the bend while it is being
+shaped. To hold it in proper form until it is set,
+blocks with curved slots may be used, or it may be
+bound with thread to a moulding block of equal
+length formed to the proper curve. When thoroughly
+dry it is to be smoothed with the emery cloth,
+and a strip of tracing cloth&mdash;glossy face out&mdash;is to
+be glued across each end, to prevent breaking in case
+of a fall. It is then to be varnished with shellac,
+and polished, as directed for the propeller. Indeed, it
+should be said once for all that every part of the
+model should be as glossy as it is possible to make
+it without adding to the weight, and that all “entering
+edges” (those which push into and divide the air
+when in flight) should be as sharp as is practicable
+with the material used.</p>
+
+<p>The steering-plane is to be fastened in place by
+a single screw long enough to pierce the plane and
+<span class="pagenum" id="Page_227">227</span>
+the supporting block, and enter the spar. The hole
+for this screw (as for all screws used) should be
+drilled carefully, to avoid the least splitting of the
+wood, and just large enough to have the screw “bite”
+without forcing its way in. This screw which holds
+the plane is to be screwed “home” but not too tight,
+so that in case the flying model should strike upon
+it in falling, the slender plane will swivel, and not
+break. It will be noticed that while this screw passes
+through the centre of the plane sideways, it is nearer
+to the forward edge than to the rear edge.</p>
+
+<p>If the work has been accurate, the plane will balance
+if the spar is supported&mdash;upon the finger, perhaps,
+as that is sensitive to any tendency to tipping.
+If either wing is too heavy, restore the balance by
+filing a little from the tip of that wing.</p>
+
+<p>The main planes are next to be made. The lower
+deck of the biplane is of the 1/16 inch whitewood, and
+the upper one is of the glazed paper upon a skeleton
+framework of wood. The upright walls are of paper.
+The wooden deck is to be bent into the proper curve
+with the aid of steam, and when dry and set in form
+is to be finished and polished. The frame for the
+upper deck is made of the thin whitewood, and is
+held to its position by two diagonal struts of whitewood
+<span class="pagenum" id="Page_228">228</span>
+bent at the ends with steam, and two straight
+upright struts or posts. It is better to bend all cross-pieces
+into the curve of the plane with steam, but
+they may be worked into the curve on the top side
+with plane and file, and left flat on the lower side.
+The drawings show full details of the construction,
+drawn accurately to scale.</p>
+
+<p>It is best to glue all joints, and in addition to insert
+tiny screws, where shown in the plans, at the time
+of gluing.</p>
+
+<p>When all the wooden parts are in place the entire
+outline of the upper plane and the upright walls is
+to be formed of silk thread carried from point to
+point, and tied upon very small pins (such as are
+used in rolls of ribbon at the stores) inserted in the
+wood. The glazed paper is put on double, glossy
+side out. Cut the pieces twice as large (and a trifle
+more) than is needed, and fold so that the smooth
+crease comes to the front and the cut edges come together
+at the rear. The two inner walls should be
+put in place first, so as to enclose the thread front
+and back, and the post, between the two leaves of the
+folded paper. Cutting the paper half an inch too
+long will give one fourth of an inch to turn flat top
+and bottom to fasten to the upper and lower decks
+<span class="pagenum" id="Page_229">229</span>
+<span class="pagenum" id="Page_230">230</span>
+respectively. The two outer walls and the upper deck
+may be cut all in one piece, the under leaf being slit
+to pass on either side of the inner walls. A bit of
+glue here and there will steady the parts to their
+places. The cut edges at the rear of the deck and
+walls should be caught together with a thin film of
+glue, so as to enclose the rear threads.</p>
+
+<div class="figcenter">
+<img src="images/i_229.jpg" alt="" />
+<blockquote>
+
+<p><i>A</i>, <i>B</i>, plan, and <i>C</i>, section, of steering plane; <i>H</i>, section of lower main plane; <i>L</i>, wood skeleton of upper
+plane; <i>T</i>, <i>T</i>, silk thread; <i>O</i>, <i>O</i>, posts; <i>J</i>, <i>J</i>, braces; <i>E</i>, rubber strands; <i>D</i>, forward hook; <i>G</i>, shaft;
+<i>F</i>, thrust-block; <i>K</i>, upper plane of paper; <i>M</i>, elevation of main planes, from the rear.</p></blockquote>
+</div>
+
+<p>When the biplane is completed it is to be fastened
+securely to the spar in such a position that it is accurately
+balanced&mdash;from side to side. The spar may
+be laid on a table, and the biplane placed across it
+in its approximate position. Then move the plane to
+one side until it tips down, and mark the spot on the
+rear edge of the plane. Repeat this operation toward
+the other side, and the centre between the two marks
+should be accurately fastened over the centre line of
+the spar. Even with the greatest care there may still
+be failure to balance exactly, but a little work with a
+file on the heavy side, or a bit of chewing gum stuck
+on the lighter side, will remedy the matter.</p>
+
+<p>The body of the aeroplane being now built, it is
+in order to fit it with propelling mechanism. The
+motive power to whirl the propeller we have already
+prepared is to be the torsion, or twisting strain&mdash;in
+this case the force of untwisting&mdash;of india rubber.
+<span class="pagenum" id="Page_231">231</span>
+When several strands of pure rubber cord are twisted
+up tight, their elasticity tends to untwist them with
+considerable force. The attachment for the rubber
+strands at the front end of the spar is a sort of bracket
+made of the brass wire. The ends of the wire are
+turned up just a little, and they are set into little
+holes in the under side of the spar. Where the wire
+turns downward to form the hook it is bound tightly
+to the spar with silk thread. The hook-shaped tip is
+formed of the loop of the wire doubled upon itself.
+The rear attachment of the rubber strands is a loop
+upon the propeller shaft itself. As shown in the
+drawings, this shaft is but a piece of the brass wire.
+On one end (the rear) an open loop is formed, and
+into this is slipped the centre of the propeller. The
+short end of the loop is then twisted around the
+longer shank&mdash;very carefully, lest the wire cut into
+and destroy the propeller. Two turns of the wire is
+enough, and then the tip of the twisted end should
+be worked down flat with the file, to serve as a bearing
+for the propeller against the thrust-block. This
+latter is made of a piece of sheet brass (a bit of
+printers’ brass “rule” is just the thing) about 1/40
+of an inch thick. It should be ¼ of an inch wide
+except at the forward end, where it is to be filed to a
+<span class="pagenum" id="Page_232">232</span>
+long point and bent up a trifle to enter the wood of
+the spar. The rear end is bent down (not too sharply,
+lest it break) to form the bearing for the propeller,
+a hole being drilled through it for the propeller shaft,
+just large enough for the shaft to turn freely in it.
+Another smaller hole is to be drilled for a little screw
+to enter the rear end of the spar. Next pass the
+straight end of the propeller shaft through the hole
+drilled for it, and with the pliers form a round hook
+for the rear attachment of the rubber strands. Screw
+the brass bearing into place, and for additional
+strength, wind a binding of silk thread around it
+and the spar.</p>
+
+<p>Tie the ends of the rubber cord together, divide it
+into ten even strands, and pass the loops over the two
+hooks&mdash;and the machine is ready for flight.</p>
+
+<p>To wind up the rubber it will be necessary to turn
+the propeller in the opposite direction to which it
+will move when the model is flying. About 100 turns
+will be required. After it is wound, hold the machine
+by the rear end of the spar, letting the propeller
+press against the hand so it cannot unwind. Raise
+it slightly above the head, holding the spar level,
+or inclined upward a little (as experience may dictate),
+and launch the model by a gentle throw forward.
+<span class="pagenum" id="Page_233">233</span>
+If the work has been well done it may fly
+from 150 to 200 feet.</p>
+
+<p>Many experiments may be made with this machine.
+If it flies too high, weight the front end of the spar;
+if too low, gliding downward from the start, weight
+the rear end. A bit of chewing gum may be enough
+to cause it to ride level and make a longer and prettier
+flight.</p>
+
+<p>A very graceful model is that of the monoplane
+type illustrated in the accompanying reproductions
+from photographs. The front view shows the little
+machine just ready to take flight from a table. The
+view from the rear is a snap-shot taken while it was
+actually flying. This successful model was made by
+Harold S. Lynn, of Stamford, Conn. Before discussing
+the details of construction, let us notice some
+peculiar features shown by the photographs. The
+forward plane is arched; that is, the tips of the plane
+bend slightly downward from the centre. On the
+contrary, the two wings of the rear plane bend slightly
+upward from the centre, making a dihedral angle,
+as it is called; that is, an angle between two surfaces,
+as distinguished from an angle between two lines.
+The toy wheels, Mr. Lynn says, are put on principally
+for “looks” but they are also useful in permitting
+<span class="pagenum" id="Page_234">234</span>
+a start to be made from a table or even from
+the floor, instead of the usual way of holding the
+model in the hands and giving it a slight throw
+to get it started. However, the wheels add to the
+weight, and the model will not fly quite so far with
+them as without.</p>
+
+<div class="figcenter">
+<img src="images/i_234.jpg" alt="" />
+<p class="caption">Front view of the Lynn model of the monoplane type, about to take flight.</p></div>
+
+<p>The wood from which this model was made was
+taken from a bamboo fish-pole, such as may be
+bought anywhere for a dime. The pole was split
+<span class="pagenum" id="Page_235">235</span>
+up, and the suitable pieces whittled and planed down
+to the proper sizes, as given in the plans. In putting
+the framework of the planes together, it is well to
+notch very slightly each rib and spar where they
+cross. Touch the joint with a bit of liquid glue, and
+wind quickly with a few turns of sewing silk and tie
+tightly. This must be done with delicacy, or the
+frames will be out of true. If the work is done rapidly
+the glue will not set until all the ties on the
+<span class="pagenum" id="Page_236">236</span>
+plane are finished. Another way is to touch the joinings
+with a drop of glue, place the ribs in position
+on the spars, and lay a board carefully on the work,
+leaving it there until all is dry, when the tying can be
+done. It either case the joinings should be touched
+again with the liquid glue and allowed to dry hard.</p>
+
+<div class="figcenter">
+<img src="images/i_235.jpg" alt="" />
+<p class="caption">The Lynn model monoplane in flight, from below and from the rear.</p></div>
+
+<p>The best material for covering these frames is the
+thinnest of China silk. If this is too expensive, use
+the thinnest cambric. But the model will not fly so
+far with the cambric covering. The material is cut
+one-fourth of an inch too large on every side, and
+folded over, and the fold glued down. Care should
+be taken that the frame is square and true before the
+covering is glued on.</p>
+
+<p>The motive power is produced by twisting up rubber
+tubing. Five and three-quarter feet of pure rubber
+tubing are required. It is tied together with silk
+so as to form a continuous ring. This is looped over
+two screw-hooks of brass, one in the rear block and
+the other constituting the shaft. This looped tubing
+is twisted by turning the propeller backward about
+two hundred turns. As it untwists it turns the propeller,
+which, in this model, is a “traction” screw,
+and pulls the machine after it as it advances through
+the air.
+<span class="pagenum" id="Page_237">237</span></p>
+
+<div class="figcenter">
+<img src="images/i_237.jpg" alt="" />
+<blockquote>
+
+<p>Details and plans of the Harold Lynn model monoplane. <i>W</i>, tail block; <i>Y</i>,
+thrust-block; <i>S</i>, mounting of propeller showing glass bead next the thrust-block,
+and one leather washer outside the screw; <i>B</i>, glass bead; <i>C</i>, tin
+washer; <i>M</i>, <i>M</i>, tin lugs holding axle of wheels.</p></blockquote>
+</div>
+
+<p><span class="pagenum" id="Page_238">238</span></p>
+
+<p>The propeller in this instance is formed from a
+piece of very thin tin, such as is used for the tops of
+cans containing condensed milk. Reference to the
+many illustrations throughout this book showing propellers
+of flying machines will give one a very good
+idea of the proper way to bend the blades. The
+mounting with the glass bead and the two leather
+washers is shown in detail in the plans.</p>
+
+<div class="figcenter">
+<img src="images/i_238.jpg" alt="" />
+<blockquote>
+
+<p>Method of forming propeller of the laminated, or layer, type. The layers
+of wood are glued,in the position shown and the blades carved out according
+to the sections. Only one blade is shown from the axle to the tip.
+This will make a right hand propeller.</p></blockquote>
+</div>
+
+<p>The wheels are taken from a toy wagon, and a
+pair of tin ears will serve as bearings for the axle.</p>
+
+<p>The sport of flying model aeroplanes has led to the
+formation of many clubs in this country as well as
+in Europe. Some of the mechanisms that have been
+<span class="pagenum" id="Page_239">239</span>
+<span class="pagenum" id="Page_240">240</span>
+devised, and some of the contrivances to make the
+models fly better and further, are illustrated in the
+drawings.</p>
+
+<div class="figcenter">
+<img src="images/i_239.jpg" alt="" />
+<blockquote>
+
+<p>At <i>A</i> is shown a method of mounting the propeller with a glass or china bead to
+reduce friction, and a brass corner to aid in strengthening. <i>B</i> shows a
+transmission of power by two spur wheels and chain. <i>C</i> is a device for
+using two rubber twists acting on the two spur wheels <i>S</i>, <i>S</i>, which in turn are
+connected with the propeller with a chain drive. <i>D</i> shows a launching
+apparatus for starting. <i>W</i>, the model; <i>V</i>, the carriage; <i>F</i>, the trigger
+guard; <i>T</i>, trigger; <i>E</i>, elastic cord for throwing the carriage forward to
+the stop <i>K</i>.</p></blockquote>
+</div>
+
+<p>Records have been made which seem marvellous
+when it is considered that 200 feet is a very good
+flight for a model propelled by rubber. For instance,
+at the contest of the Birmingham Aero Club (England)
+in September, one of the contestants won the
+prize with a flight of 447 feet, lasting 48 seconds.
+The next best records for duration of flight were 39
+seconds and 38 seconds. A model aeroplane which
+is “guaranteed to fly 1,000 feet,” according to the
+advertisement in an English magazine, is offered for
+sale at $15.</p>
+
+<p>The American record for length of flight is held
+by Mr. Frank Schober, of New York, with a distance
+of 215 feet 6 inches. His model was of the
+Langley type of tandem monoplane, and very highly
+finished. The problem is largely one of adequate
+power without serious increase of weight.
+<span class="pagenum" id="Page_241">241</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XII">Chapter XII.<br />
+
+THE GLIDER.</h2>
+
+<blockquote>
+
+<p>Aerial balancing&mdash;Practice necessary&mdash;Simplicity of the glider
+Materials&mdash;Construction&mdash;Gliding&mdash;Feats with the Montgomery
+glider&mdash;Noted experimenters&mdash;Glider clubs.</p></blockquote>
+
+<p class="drop"><span class="uppercase">It</span> is a matter of record that the Wright brothers
+spent the better part of three years among the
+sand dunes of the North Carolina sea-coast practising
+with gliders. In this way they acquired that confidence
+while in the air which comes from intimate acquaintance
+with its peculiarities, and which cannot be
+gained in any other way. It is true that the Wrights
+were then developing not only themselves, but also
+their gliders; but the latter work was done once for
+all. To develop aviators, however, means the repeating
+of the same process for each individual&mdash;just
+as each for himself must be taught to read. And the
+glider is the “First Reader” in aeronautics.</p>
+
+<p>The long trail of wrecks of costly aeroplanes marking
+the progress in the art of flying marks also the
+<span class="pagenum" id="Page_242">242</span>
+lack of preparatory training, which their owners
+either thought unnecessary, or hoped to escape by
+some royal road less wearisome than persistent personal
+practice. But they all paid dearly to discover
+that there is no royal road. Practice, more practice,
+and still more practice&mdash;that is the secret of successful
+aeroplane flight.</p>
+
+<p>For this purpose the glider is much superior to
+the power-driven aeroplane. There are no controls
+to learn, no mechanism to manipulate. One simply
+launches into the air, and concentrates his efforts
+upon balancing himself and the apparatus; not as two
+distinct bodies, however, but as a united whole. When
+practice has made perfect the ability to balance the
+glider instinctively, nine-tenths of the art of flying
+an aeroplane has been achieved. Not only this, but
+a new sport has been laid under contribution; one
+beside which coasting upon a snow-clad hillside is a
+crude form of enjoyment.</p>
+
+<p>Fortunately for the multitude, a glider is easily
+made, and its cost is even less than that of a bicycle.
+A modest degree of skill with a few carpenter’s tools,
+and a little “gumption” about odd jobs in general,
+is all that is required of the glider builder.</p>
+
+<div class="figcenter">
+<img src="images/i_243.jpg" alt="" />
+<p class="caption">A gliding slope with starting platform, erected for club use.</p></div>
+
+<p>The frame of the glider is of wood, and spruce is
+<span class="pagenum" id="Page_243">243</span>
+<span class="pagenum" id="Page_244">244</span>
+recommended, as it is stronger and tougher for its
+weight than other woods. It should be of straight
+grain and free from knots; and as there is considerable
+difference in the weight of spruce from different
+trees, it is well to go over the pile in the lumber yard
+and pick out the lightest boards. Have them planed
+down smooth on both sides, and to the required thickness,
+at the mill&mdash;it will save much toilsome hand
+work. The separate parts may also be sawed out at
+the mill, if one desires to avoid this labor.</p>
+
+<p>The lumber needed is as follows:</p>
+
+<table>
+  <tr class="tdr">
+    <td>4</td>
+    <td class="tdl">spars</td>
+    <td style="padding: 0 2em">20 ft. long,</td>
+    <td>1¼ in. wide,</td>
+    <td>¾ in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td>12</td>
+    <td class="tdl">struts</td>
+    <td style="padding: 0 2em">3 ft. long,</td>
+    <td>1¼ in. wide,</td>
+    <td>¾ in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td>2</td>
+    <td class="tdl">rudder bars</td>
+    <td style="padding: 0 2em">8 ft. long,</td>
+    <td>¾ in. wide,</td>
+    <td>½ in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td>12</td>
+    <td class="tdl">posts</td>
+    <td style="padding: 0 2em">4 ft. long,</td>
+    <td>1½ in. wide,</td>
+    <td>½ in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td>41</td>
+    <td class="tdl">ribs</td>
+    <td style="padding: 0 2em">4 ft. long,</td>
+    <td>½ in. wide,</td>
+    <td>½ in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td>2</td>
+    <td class="tdl">arm rests</td>
+    <td style="padding: 0 2em">4 ft. long,</td>
+    <td>2 in. wide,</td>
+    <td>1 in. thick.</td>
+  </tr>
+  <tr class="tdr">
+    <td class="tdl" colspan="2">For rudder frame.</td>
+    <td class="tdc">24 running ft.,</td>
+    <td>1 in. wide,</td>
+    <td>1 in. thick.</td>
+  </tr>
+</table>
+
+<p>If it be impossible to find clear spruce lumber 20
+feet in length, the spars may be built up by splicing
+two 10-foot sticks together. For this purpose, the
+splicing stick should be as heavy as the single spar&mdash;1¼
+inches wide, and ¾ inches thick&mdash;and at least 4 feet
+long, and be bolted fast to the spar with six ⅛ inch
+round-head carriage bolts with washers of large bearing
+surface (that is, a small hole to fit the bolt, and a
+<span class="pagenum" id="Page_245">245</span>
+large outer diameter) at both ends of the bolt, to prevent
+crushing the wood. A layer of liquid glue
+brushed between will help to make the joint firmer.</p>
+
+<div class="figcenter">
+<img src="images/i_245.jpg" alt="" />
+<p class="caption">Otto Lilienthal in his single-plane glider. The swinging forward of his feet
+tends to turn the glider toward the ground, and increase its speed.</p></div>
+
+<p>Wherever a bolt is put in, a hole should be bored
+for it with a bit of such size that the bolt will fit
+snug in the hole without straining the grain of the
+wood.</p>
+
+<p>The corners of the finished spar are to be rounded
+off on a large curvature.
+<span class="pagenum" id="Page_246">246</span></p>
+
+<p>The ends of the struts are to be cut down on a
+slight slant of about 1/16 inch in the 1¼ inches that
+it laps under the spar&mdash;with the idea of tipping the
+top of the spar forward so that the ribs will spring
+naturally from it into the proper curve.</p>
+
+<p>The ribs should be bent by steaming, and allowed
+to dry and set in a form, or between blocks nailed
+upon the floor to the line of the correct curve. They
+are then nailed to the frames, the front end first:
+21 to the frame of the upper plane, and 20 to that
+of the lower plane, omitting one at the centre, where
+the arm pieces will be placed.</p>
+
+<p>Some builders tack the ribs lightly into place with
+small brads, and screw clamps formed from sheet
+brass or aluminum over them. Others use copper
+nails and clinch them over washers on the under side.
+Both methods are shown in the plans, but the clamps
+are recommended as giving greater stiffness, an essential
+feature.</p>
+
+<p>At the front edge of the frames the ribs are fastened
+flush, and being 4 feet long and the frame but
+3 feet wide, they project over the rear about 1 foot.</p>
+
+<p>The arm pieces are bolted to the spars of the lower
+frame 6½ inches on each side of the centre, so as to
+allow a free space of 13 inches between them. This
+<span class="pagenum" id="Page_247">247</span>
+<span class="pagenum" id="Page_248">248</span>
+opening may be made wider to accommodate a stouter
+person.</p>
+
+<div class="figcenter">
+<img src="images/i_247.jpg" alt="" />
+<p class="caption">Plan and details of Glider. The upper plane has a rib at the centre instead of the two arm pieces.</p></div>
+
+<p>The posts are then put into place and bolted to
+the struts and the spars, as shown, with ⅛inch bolts.</p>
+
+<p>The entire structure is then to be braced diagonally
+with No. 16 piano wire. The greatest care must be
+taken to have these diagonals pull just taut, so that
+they shall not warp the lines of the frames out of true.
+A crooked frame will not fly straight, and is a source
+of danger when making a landing.</p>
+
+<p>The frames are now to be covered. There is a
+special balloon cloth made which is best for the purpose,
+but if that cannot be procured, strong cambric
+muslin will answer. Thirty yards of goods 1 yard
+wide will be required for the planes and the rudder.
+From the piece cut off 7 lengths for each plane,
+4 feet 6 inches long. These are to be sewed together,
+selvage to selvage, so as to make a sheet about 19
+feet 6 inches long and 4 feet 6 inches wide. As this
+is to be tacked to the frame, the edges must be double-hemmed
+to make them strong enough to resist tearing
+out at the tacks. Half an inch is first folded down
+all around; the fold is then turned back on the goods
+2½ inches and sewed. This hem is then folded back
+1 inch upon itself, and again stitched. Strips 3
+<span class="pagenum" id="Page_249">249</span>
+inches wide and a little over 4 feet long are folded
+“three-double” into a width of 1 inch, and sewed
+along both edges to the large sheet exactly over where
+the ribs come. These are to strengthen the fabric
+where the ribs press against it. Sixteen-ounce tacks
+are used, being driven through a felt washer the size
+of a gun wad at intervals of four inches. If felt is
+not readily obtainable, common felt gun wads will do.
+The tacking is best begun at the middle of the frame,
+having folded the cloth there to get the centre. Then
+stretch smoothly out to the four corners and tack at
+each. It may then be necessary to loosen the two
+centre tacks and place them over again, to get rid of
+wrinkles. The next tacks to drive are at the ends
+of the struts; then half-way between; and so on until
+all are in, and the sheet is taut and smooth. For
+a finer finish, brass round-head upholsterer’s nails
+may be used.</p>
+
+<p>The rudder, so-called, is rather a tail, for it is not
+movable and does not steer the glider. It does steady
+the machine, however, and is very important in preserving
+the equilibrium when in flight. It is formed
+of two small planes intersecting each other at right
+angles and covered on both sides with the cloth, the
+sections covering the vertical part being cut along
+<span class="pagenum" id="Page_250">250</span>
+the centre and hemmed on to the upper and lower
+faces of the horizontal part. The frame for the vertical
+part is fastened to the two rudder bars which
+stretch out toward the rear, one from the upper
+plane, and the other from the lower. The whole construction
+is steadied by guys of the piano wire.</p>
+
+<div class="figcenter">
+<img src="images/i_250.jpg" alt="" />
+<p class="caption">Lilienthal in his double-deck glider. It proved unmanageable and fell, causing
+his death. The hill is an artificial one built for his own use in experimenting.</p></div>
+
+<p>All wooden parts should be smoothed off with sandpaper,
+and given a coat of shellac varnish.</p>
+
+<p>To make a glide, the machine is taken to an elevated
+<span class="pagenum" id="Page_251">251</span>
+<span class="pagenum" id="Page_252">252</span>
+point on a slope, not far up to begin with.
+Lift the glider, get in between the arm rests, and
+raise the apparatus until the rests are snug under
+the arms. Run swiftly for a few yards and leap
+into the air, holding the front of the planes slightly
+elevated. If the weight of the body is in the right
+position, and the speed sufficient, the glider will take
+the air and sail with you down the slope. It may be
+necessary at first to have the help of two assistants,
+one at each end, to run with the glider for a good
+start.</p>
+
+<div class="figcenter">
+<img src="images/i_251.jpg" alt="" />
+<p class="caption">Diagram showing differing lines of flight as controlled by changing the position of the body. The wind must be blowing
+against the direction of flight; in the illustration this would be from left to right.</p></div>
+
+<p>The position of the body on the arm rests can best
+be learned by a few experiments. No two gliders are
+quite alike in this respect, and no rule can be given.
+As to the requisite speed, it must be between 15 and
+20 miles an hour; and as this speed is impossible to
+a man running, it is gained by gliding against the
+wind, and thus adding the speed of the wind to the
+speed of the runner. The Wrights selected the sand
+dunes of the North Carolina coast for their glider
+experiments because of the steady winds that blow
+in from the ocean, across the land. These winds
+gave them the necessary speed of air upon which to
+sail their gliders.</p>
+
+<p>The first flights attempted should be short, and
+<span class="pagenum" id="Page_253">253</span>
+as experience is gained longer ones may be essayed.</p>
+
+<p>Balancing the glider from side to side is accomplished
+by swaying the lower part of the body like a
+pendulum, the weight to go toward the side which
+has risen. Swinging the body forward on the arm
+rests will cause the machine to dip the planes and
+glide more swiftly down the incline. Holding the
+weight of the body back in the arm rests will cause
+the machine to fly on a higher path and at a slower
+speed. This is objectionable because the glider is
+more manageable at a higher speed, and therefore
+safer. The tendency at first is to place the weight
+too far back, with a consequent loss of velocity, and
+with that a proportionate loss of control. The proper
+position of the body is slightly forward of the mechanical
+centre of the machine.</p>
+
+<p>The landing is accomplished by shoving the body
+backward, thus tilting up the front of the plane.
+This checks the speed, and when the feet touch the
+ground a little run, while holding back, will bring
+the glide to an end. Landing should be practised
+often with brief glides until skill is gained, for it is
+the most difficult operation in gliding.</p>
+
+<p>After one becomes expert, longer flights may be
+<span class="pagenum" id="Page_254">254</span>
+secured by going to higher points for the start. From
+an elevation of 300 feet a glide of 1,200 feet is possible.</p>
+
+<div class="figcenter">
+<img src="images/i_254.jpg" alt="" />
+<p class="caption">Gliding with a Chanute three-decker. A start with two assistants.</p></div>
+
+<p>While it is necessary to make glides against the
+wind, it is not wise to attempt flights when the wind
+blows harder than 10 miles an hour. While the
+flight may be successful, the landing may be disastrous.</p>
+
+<p>The accomplished glider operator is in line for
+the aeroplane, and it is safe to say that he will not
+<span class="pagenum" id="Page_255">255</span>
+be long without one. The skilful and practised operator
+of a glider makes the very best aeroplane
+pilot.</p>
+
+<p>This chapter would not be complete without an
+adequate reference to the gliders devised by Professor
+Montgomery of Santa Clara, California. These machines
+were sent up with ordinary hot-air balloons
+to various heights, reaching 4,000 feet in some instances,
+when they were cut loose and allowed to
+descend in a long glide, guided by their pilots. The
+time of the descent from the highest altitude was
+twenty minutes, during which the glider travelled
+about eight miles. The landing was made accurately
+upon a designated spot, and so gently that there was
+no perceptible jar. Two of the pilots turned completely
+over sideways, the machine righting itself
+after the somersault and continuing its regular course.
+Professor Montgomery has made the assertion that
+he can fasten a bag of sand weighing 150 lbs. in the
+driver’s seat of his glider, and send it up tied upside
+down under a balloon, and that after being cut
+loose, the machine will right itself and come safely
+to the ground without any steering.</p>
+
+<p>Lilienthal in Germany, Pilcher in England, and
+Chanute in the United States are names eminent in
+<span class="pagenum" id="Page_256">256</span>
+connection with the experiments with gliders which
+have been productive of discoveries of the greatest
+importance to the progress of aviation. The illustration
+of the Chanute glider shows its peculiarities
+plainly enough to enable any one to comprehend
+them.</p>
+
+<p>The establishment of glider clubs in several parts
+of the country has created a demand for ready-made
+machines, so that an enthusiast who does not wish
+to build his own machine may purchase it ready
+made.
+<span class="pagenum" id="Page_257">257</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XIII">Chapter XIII.<br />
+
+BALLOONS.</h2>
+
+<blockquote>
+
+<p>First air vehicle&mdash;Principle of Archimedes&mdash;Why balloons rise&mdash;Inflating
+gases&mdash;Early history&mdash;The Montgolfiers&mdash;The
+hot-air balloon&mdash;Charles’s hydrogen balloon&mdash;Pilatre de
+Rozier&mdash;The first aeronaut&mdash;The first balloon voyage&mdash;Blanchard
+and Jeffries&mdash;Crossing the English Channel&mdash;First
+English ascensions&mdash;Notable voyages&mdash;Recent long-distance
+journeys and high ascensions&mdash;Prize balloon
+races&mdash;A fascinating sport&mdash;Some impressions, adventures,
+and hardships&mdash;Accident record&mdash;Increasing interest in
+ballooning.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> balloon, though the earliest and crudest
+means of getting up in the air, has not become
+obsolete. It has been in existence practically
+in its present general form for upwards of 500 years.
+Appliances have been added from time to time, but
+the big gas envelope enclosing a volume of some gas
+lighter than an equal volume of air, and the basket,
+or car, suspended below it, remain as the typical form
+of aerial vehicle which has not changed since it was
+first devised in times so remote as to lie outside the
+boundaries of recorded history.
+<span class="pagenum" id="Page_258">258</span></p>
+
+<p>The common shape of the gas bag of a balloon is
+that of the sphere, or sometimes of an inverted pear.
+It is allowed to rise and float away in the air as the
+prevailing wind may carry it. Attempts have been
+made to steer it in a desired direction, but they
+did not accomplish much until the gas bag was made
+long horizontally, in proportion to its height and
+width. With a drag-rope trailing behind on the
+ground from the rear end of the gas bag, and sails
+on the forward end, it was possible to guide the
+elongated balloon to some extent in a determined
+direction.</p>
+
+<p>In explaining why a balloon rises in the air, it is
+customary to quote the “principle of Archimedes,”
+discovered and formulated by that famous philosopher
+centuries before the Christian era. Briefly
+stated, it is this: Every body immersed in a fluid is
+acted upon by a force pressing upward, which is
+equal to the weight of the amount of the fluid displaced
+by the immersed body.</p>
+
+<p>It remained for Sir Isaac Newton to explain the
+principle of Archimedes (by the discovery of the law
+of gravitation), and to show that the reason why the
+immersed body is apparently pushed upward, is that
+the displaced fluid is attracted downward. In the
+<span class="pagenum" id="Page_259">259</span>
+case of a submerged bag of a gas lighter than air,
+the amount of force acting on the surrounding air
+is greater than that acting on the gas, and the latter
+is simply crowded out of the way by the descending
+air, and forced up to a higher level where its lighter
+bulk is balanced by the gravity acting upon it.</p>
+
+<p>The fluid in which the balloon is immersed is the
+air. The force with which the air crowds down
+around and under the balloon is its weight&mdash;weight
+being the measure of the attraction which gravity
+exerts upon any substance.</p>
+
+<p>The weight of air at a temperature of 32° Fahr.,
+at the normal barometer pressure at the sea-level
+(29.92 inches of mercury), is 0.0807 lbs. per cubic
+foot. The gas used to fill a balloon must therefore
+weigh less than this, bulk for bulk, in order to be
+crowded upward by the heavier air&mdash;and thus exert
+its “lifting power,” as it is commonly called.</p>
+
+<p>In practice, two gases have been used for inflating
+balloons&mdash;hydrogen, and illuminating gas, made ordinarily
+from coal, and called “coal gas.” Hydrogen
+is the lightest substance known; that is, it is
+attracted less by gravity than any other known substance,
+in proportion to its bulk.</p>
+
+<div class="figcenter">
+<img src="images/i_260.jpg" alt="" />
+<p class="caption">One of the earliest attempts to steer a spherical balloon by retarding its
+speed with the drag-rope, and adjusting the sail to the passing wind.</p></div>
+
+<p>A cubic foot of hydrogen weighs but 0.0056 lbs.,
+<span class="pagenum" id="Page_260">260</span>
+<span class="pagenum" id="Page_261">261</span>
+and it will therefore be pushed upward in air by
+the difference in weight, or 0.0751 lbs. per cubic foot.
+A cubic foot of coal gas weighs about 0.0400 lbs., and
+is crowded upward in air with a force of 0.0407 lbs.</p>
+
+<div class="figcenter">
+<img src="images/i_261.jpg" alt="" />
+<blockquote>
+
+<p>Apparatus to illustrate the principle of Archimedes. At the left, the small
+solid glass ball and large hollow glass sphere are balanced in the free air.
+When the balance is moved under the bell-glass of the air pump (at the
+right), and the air exhausted, the large sphere drops, showing that its
+previous balance was due to the upward pressure of the air, greater
+because of its larger bulk.</p></blockquote>
+</div>
+
+<p>It is readily seen that a very large bulk of hydrogen
+must be used if any considerable weight is to be
+lifted. For to the weight of the gas must be added
+the weight of the containing bag, the car, and the
+network supporting it, the ballast, instruments, and
+<span class="pagenum" id="Page_262">262</span>
+passengers, and there must still be enough more to
+afford elevating power sufficient to raise the entire
+load to the desired level.</p>
+
+<p>Let us assume that we have a balloon with a volume
+of 20,000 cubic feet, which weighs with its
+appurtenances 500 pounds. The hydrogen it would
+contain would weigh about 112 pounds, and the
+weight of the air it would displace would be about
+1,620 pounds. The total available lifting power
+would be about 1,000 pounds. If a long-distance
+journey is to be undertaken at a comparatively low
+level, this will be sufficient to carry the necessary
+ballast, and a few passengers. If, however, it is intended
+to rise to a great height, the problem is different.
+The weight of the air, and consequently its
+lifting pressure, decreases as we go upwards. If the
+balloon has not been entirely filled, the gas will expand
+as the pressure is reduced in the higher altitude.
+This has the effect of carrying the balloon
+higher. Heating of the contained gas by the sun will
+also cause a rise. On the other hand, the diffusion
+of the gas through the envelope into the air, and the
+penetration of air into the gas bag will produce a
+mixture heavier than hydrogen, and will cause the
+balloon to descend. The extreme cold of the upper
+<span class="pagenum" id="Page_263">263</span>
+air has the same effect, as it tends to condense to a
+smaller bulk the gas in the balloon. To check a
+descent the load carried by the gas must be lightened
+by throwing out some of the ballast, which is carried
+simply for this purpose. Finally a level is reached
+where equilibrium is established, and above which
+it is impossible to rise.</p>
+
+<p>The earliest recorded ascent of a balloon is credited
+to the Chinese, on the occasion of the coronation
+of the Emperor Fo-Kien at Pekin in the year
+1306. If this may be called historical, it gives evidence
+also that it speedily became a lost art. The
+next really historic record belongs in the latter part
+of the seventeenth century, when Cyrano de Bergerac
+attempted to fly with the aid of bags of air attached
+to his person, expecting them to be so expanded by
+the heat of the sun as to rise with sufficient force to
+lift him. He did not succeed, but his idea is plainly
+the forerunner of the hot-air balloon.</p>
+
+<p>In the same century Francisco de Lana, who was
+clearly a man of much intelligence and keen reasoning
+ability, having determined by experiment that the
+atmosphere had weight, decided that he would be able
+to rise into the air in a ship lifted by four metal
+spheres 20 feet in diameter from which the air had
+<span class="pagenum" id="Page_264">264</span>
+been exhausted. After several failures he abandoned
+his efforts upon the religious grounds that the
+Almighty doubtless did not approve such an overturning
+in the affairs of mankind as would follow
+the attainment of the art of flying.</p>
+
+<p>In 1757, Galen, a French monk, published a book,
+“The Art of Navigating in the Air,” in which he
+advocated filling the body of the airship with air
+secured at a great height above the sea-level, where
+it was “a thousand times lighter than water.” He
+showed by mathematical computations that the upward
+impulse of this air would be sufficient to lift a
+heavy load. He planned in detail a great airship to
+carry 4,000,000 persons and several million packages
+of goods. Though it may have accomplished
+nothing more, this book is believed to have been the
+chief source of inspiration to the Montgolfiers.</p>
+
+<p>The discovery of hydrogen by Cavendish in 1776
+gave Dr. Black the opportunity of suggesting that it
+be used to inflate a large bag and so lift a heavy load
+into the air. Although he made no attempt to construct
+such an apparatus, he afterward claimed that
+through this suggestion he was entitled to be called
+the real inventor of the balloon.</p>
+
+<p>This is the meagre historical record preceding the
+<span class="pagenum" id="Page_265">265</span>
+achievements of the brothers Stephen and Joseph
+Montgolfier, which marked distinctly the beginning
+of practical aeronautics. Both of these men were
+highly educated, and they were experienced workers
+in their father’s paper factory. Joseph had made
+some parachute drops from the roof of his house as
+early as 1771.</p>
+
+<p>After many experiments with steam, smoke, and
+hydrogen gas, with which they tried ineffectually to
+inflate large paper bags, they finally succeeded with
+heated air, and on June 5, 1783, they sent up a
+great paper hot-air balloon, 35 feet in diameter.
+It rose to a height of 1,000 feet, but soon came to
+earth again upon cooling. It appears that the Montgolfiers
+were wholly ignorant of the fact that it
+was the rarefying of the air by heating that caused
+their balloon to rise, and they made no attempt
+to keep it hot while the balloon was in the air.</p>
+
+<div class="figcenter">
+<img src="images/i_266.jpg" alt="" />
+<p class="caption">An early Montgolfier balloon.</p></div>
+
+<p>About the same time the French scientist, M.
+Charles, decided that hydrogen gas would be better
+than hot air to inflate balloons. Finding that this
+gas passed readily through paper, he used silk coated
+with a varnish made by dissolving rubber. His balloon
+was 13 feet in diameter, and weighed about
+20 pounds. It was sent up from the Champ de
+<span class="pagenum" id="Page_266">266</span>
+Mars on August 29, 1783, amidst the booming of
+cannon, in the presence of 300,000 spectators who
+assembled despite a heavy rain. It rose swiftly, disappearing
+among the clouds, and soon burst from
+the expansion of the gas in the higher and rarer atmosphere&mdash;no
+allowance having been made for this
+<span class="pagenum" id="Page_267">267</span>
+unforeseen result. It fell in a rural region near Paris,
+where it was totally destroyed by the inhabitants, who
+believed it to be some hideous form of the devil.</p>
+
+<p>The Montgolfiers had already come to Paris, and
+had constructed a balloon of linen and paper. Before
+they had opportunity of sending it up it was
+ruined by a rainstorm with a high wind. They immediately
+built another of waterproof linen which
+made a successful ascension on September 19, 1783,
+taking as passengers a sheep, a cock, and a duck.
+The balloon came safely to earth after being up eight
+minutes&mdash;falling in consequence of a leak in the air-bag
+near the top. The passengers were examined
+with great interest. The sheep and the duck seemed
+in the same excellent condition as when they went
+up, but the cock was evidently ailing. A consultation
+of scientists was held and it was the consensus
+of opinion that the fowl could not endure breathing
+the rarer air of the high altitude. At this juncture
+some one discovered that the cock had been trodden
+upon by the sheep, and the consultation closed
+abruptly.</p>
+
+<p>The Montgolfier brothers were loaded with honors,
+Stephen receiving the larger portion; and the
+people of Paris entered enthusiastically into the sport
+<span class="pagenum" id="Page_268">268</span>
+of making and flying small balloons of the Montgolfier
+type.</p>
+
+<p>Stephen began work at once upon a larger balloon
+intended to carry human passengers. It was fifty
+feet in diameter, and 85 feet high, with a capacity
+of 100,000 cubic feet. The car for the passengers
+was swung below from cords in the fashion that has
+since become so familiar.</p>
+
+<p>In the meantime Pilatre de Rozier had constructed
+a balloon on the hot-air principle, but with an arrangement
+to keep the air heated by a continuous
+fire in a pan under the mouth of the balloon. He
+made the first balloon ascent on record on October
+15, 1783, rising to a height of eighty feet, in the captive
+balloon. On November 21, in the same year, de
+Rozier undertook an expedition in a free balloon with
+the Marquis d’Arlandes as a companion. The experiment
+was to have been made with two condemned
+criminals, but de Rozier and d’Arlandes succeeded in
+obtaining the King’s permission to make the attempt,
+and in consequence their names remain as those of
+the first aeronauts. They came safely to the ground
+after a voyage lasting twenty-five minutes. After
+this, ascensions speedily became a recognized sport,
+even for ladies.
+<span class="pagenum" id="Page_269">269</span></p>
+
+<p>The greatest altitude reached by these hot-air balloons
+was about 9,000 feet.</p>
+
+<div class="figcenter">
+<img src="images/i_269.jpg" alt="" />
+<p class="caption">Pilatre de Rozier’s balloon.</p></div>
+
+<p>The great danger from fire, however, led to the
+closer consideration of the hydrogen balloon of Professor
+Charles, who was building one of 30 feet diameter
+for the study of atmospheric phenomena. His
+<span class="pagenum" id="Page_270">270</span>
+mastery of the subject is shown by the fact that his
+balloon was equipped with almost every device afterward
+in use by the most experienced aeronauts. He
+invented the valve at the top of the bag for allowing
+the escape of gas in landing, the open neck to permit
+expansion, the network of cords to support the car,
+the grapnel for anchoring, and the use of a small
+pilot balloon to test the air-currents before the ascension.
+He also devised a barometer by which he was
+able to measure the altitude reached by the pressure
+of the atmosphere.</p>
+
+<p>To provide the hydrogen gas required he used the
+chemical method of pouring dilute sulphuric acid on
+iron filings. The process was so slow that it took
+continuous action for three days and three nights to
+secure the 14,000 cubic feet needed, but his balloon
+was finally ready on December 1, 1783. One of the
+brothers Robert accompanied Charles, and they travelled
+about 40 miles in a little less than 4 hours,
+alighting at Nesles. Here Robert landed and Charles
+continued the voyage alone. Neglecting to take on
+board ballast to replace the weight of M. Robert,
+Charles was carried to a great height, and suffered
+severely from cold and the difficulty of breathing in
+the highly rarefied air. He was obliged to open his
+<span class="pagenum" id="Page_271">271</span>
+gas valve and descend after half an hour’s flight
+alone.</p>
+
+<p>Blanchard, another French inventor, about this
+time constructed a balloon with the intention of being
+the first to cross the English Channel in the air.
+He took his balloon to Dover and with Dr. Jeffries,
+an American, started on January 7, 1785. His balloon
+was leaky and he had loaded it down with a lot
+of useless things in the way of oars, provisions, and
+other things. All of this material and the ballast
+had to be thrown overboard at the outset, and books
+and parts of the balloon followed. Even their clothing
+had to be thrown over to keep the balloon out of
+the sea, and at last, when Dr. Jeffries had determined
+to jump out to enable his friend to reach the
+shore, an upward current of wind caught them and
+with great difficulty they landed near Calais. The
+feat was highly lauded and a monument in marble
+was erected on the spot to perpetuate the record of
+the achievement.</p>
+
+<p>De Rozier lost his life soon after in the effort to
+duplicate this trip across the Channel with his combination
+hydrogen and hot-air balloon. His idea seems
+to have been that he could preserve the buoyancy of
+his double balloon by heating up the air balloon at intervals.
+<span class="pagenum" id="Page_272">272</span>
+<span class="pagenum" id="Page_273">273</span>
+Unfortunately, the exuding of the hydrogen
+as the balloons rose formed an explosive mixture with
+the air he was rising through, and it was drawn to
+his furnace, and an explosion took place which blew
+the entire apparatus into fragments at an altitude of
+over 1,000 feet.</p>
+
+<div class="figcenter">
+<img src="images/i_272.jpg" alt="" />
+<p class="caption">Car and hoop of the Blanchard balloon, the first to cross the English Channel.</p></div>
+
+<p>Count Zambeccari, an Italian, attempted to improve
+the de Rozier method of firing a balloon by substituting
+a large alcohol lamp for the wood fire. In
+the first two trial trips he fell into the sea, but was
+rescued. On the third trip his balloon was swept
+into a tree, and the overturned lamp set it on fire.
+To escape being burned, he threw himself from the
+balloon and was killed by the fall.</p>
+
+<p>The year before these feats on the Continent two
+notable balloon ascensions had taken place in England.
+On August 27, 1784, an aeronaut by the name
+of Tytler made the first balloon voyage within the
+boundaries of Great Britain. His balloon was of
+linen and varnished, and the record of his ascension
+indicates that he used hydrogen gas to inflate it.
+He soared to a great height, and descended safely.</p>
+
+<p>A few weeks later, the Italian aeronaut Lunardi
+made his first ascent from London. The spectacle
+drew the King and his councillors from their deliberations,
+<span class="pagenum" id="Page_274">274</span>
+and the balloon was watched until it disappeared.
+He landed in Standon, near Ware, where
+a stone was set to record the event. On October 12,
+he made his famous voyage from Edinburgh over the
+Firth of Forth to Ceres; a distance of 46 miles in
+35 minutes, or at the rate of nearly 79 miles per
+hour; a speed rarely equalled by the swiftest railroad
+trains.</p>
+
+<p>From this time on balloons multiplied rapidly and
+the ascents were too numerous for recording in these
+pages. The few which have been selected for mention
+are notable either for the great distances traversed,
+or for the speed with which the journeys were
+made. It should be borne in mind that the fastest
+method of land travel in the early part of the period
+covered was by stage coach; and the sailing ship was
+the only means of crossing the water. It is no wonder
+that often the people among whom the aeronauts
+landed on a balloon voyage refused to believe the
+statements made as to the distance they had come,
+and the marvellously short time it had taken. And
+even as compared with the most rapid transit of the
+present day, the speeds attained in many cases have
+never been equalled.</p>
+
+<p>A remarkable English voyage was made in June,
+<span class="pagenum" id="Page_275">275</span>
+1802, by the French aeronaut Garnerin and Captain
+Snowdon. They ascended from Chelsea Gardens and
+landed in Colchester, 60 miles distant, in 45 minutes:
+an average speed of 80 miles an hour.</p>
+
+<p>On December 16, 1804, Garnerin ascended from
+the square in front of Notre Dame, Paris; passing
+over France and into Italy, sailing above St. Peter’s
+at Rome, and the Vatican, and descending into Lake
+Bracciano&mdash;a distance of 800 miles in 20 hours.
+This voyage was made as a part of the coronation
+ceremonies of Napoleon I. The balloon was afterwards
+hung up in a corridor of the Vatican.</p>
+
+<p>On October 7, 1811, Sadler and Burcham voyaged
+from Birmingham to Boston (England), 112 miles
+in 1 hour 40 minutes, a speed of 67 miles per hour.</p>
+
+<p>On November 17, 1836, Charles Green and Monck
+Mason started on a voyage in the great balloon of the
+Vauxhall Gardens. It was pear-shaped, 60 feet
+high and 50 feet in diameter, and held 85,000 cubic
+feet of gas. It was cut loose at half-past one in the
+afternoon, and in 3 hours had reached the English
+Channel, and in 1 hour more had crossed it,
+and was nearly over Calais. During the night it
+floated on over France in pitchy darkness and such
+intense cold that the oil was frozen. In the morning
+<span class="pagenum" id="Page_276">276</span>
+<span class="pagenum" id="Page_277">277</span>
+the aeronauts descended a few miles from Weilburg,
+in the Duchy of Nassau, having travelled about
+500 miles in 18 hours. At that date, by the fastest
+coaches the trip would have consumed three
+days. The balloon was rechristened “The Great
+Balloon of Nassau” by the enthusiastic citizens of
+Weilburg.</p>
+
+<div class="figcenter">
+<img src="images/i_276.jpg" alt="" />
+<blockquote>
+
+<p>Prof. T. S. C. Lowe’s mammoth balloon “City of New York,” a feature of
+the year 1860, in which it made many short voyages in the vicinity of
+New York and Philadelphia.</p></blockquote>
+</div>
+
+<p>In 1849, M. Arban crossed the Alps in a balloon,
+starting at Marseilles and landing at Turin&mdash;a distance
+of 400 miles in 8 hours. This remarkable record
+for so long a distance at a high speed has rarely
+been equalled. It was exceeded as to distance at the
+same speed by the American aeronaut, John Wise, in
+1859.</p>
+
+<p>One of the most famous balloons of recent times
+was the “Geant,” built by M. Nadar, in Paris, in
+1853. The immense gas-bag was made of silk of the
+finest quality costing at that time about $1.30 a yard,
+and being made double, it required 22,000 yards. It
+had a capacity of 215,000 cubic feet of gas, and lifted
+4½ tons. The car was 13 feet square, and had an
+upper deck which was open. On its first ascent it
+carried 15 passengers, including M. Nadar as captain,
+and the brothers Godard as lieutenants. A few
+weeks later this balloon was set free for a long-distance
+<span class="pagenum" id="Page_278">278</span>
+journey, and 17 hours after it left Paris it
+landed at Nieuburg in Hanover, having traversed
+750 miles, a part of the time at the speed of fully
+90 miles per hour.</p>
+
+<p>In July, 1859, John Wise, an American aeronaut,
+journeyed from St. Louis, Mo., to Henderson, N. Y.,
+a distance of 950 miles in 19 hours. His average
+speed was 50 miles per hour. This record for duration
+at so high a rate of speed has never been exceeded.</p>
+
+<p>During the siege of Paris in 1870, seventy-three
+balloons were sent out from that city carrying mail
+and dispatches. These were under Government direction,
+and receive notice in a subsequent chapter
+devoted to Military Aeronautics. One of these balloons
+is entitled to mention among those famous for
+rapid journeys, having travelled to the Zuyder Zee, a
+distance of 285 miles, in 3 hours&mdash;an average speed
+of 95 miles per hour. Another of these postal balloons
+belongs in the extreme long-distance class, having
+come down in Norway nearly 1,000 miles from
+Paris.</p>
+
+<p>In July, 1897, the Arctic explorer Andrée started
+on his voyage to the Pole. As some of his instruments
+have been recently recovered from a wandering
+<span class="pagenum" id="Page_279">279</span>
+band of Esquimaux, it is believed that a record
+of his voyage may yet be secured.</p>
+
+<p>In the same year a balloon under the command of
+Godard ascended at Leipsic, and after a wandering
+journey in an irregular course, descended at Wilna.
+The distance travelled was estimated at 1,032 miles,
+but as balloon records are always based on the airline
+distance between the places of ascent and descent,
+this record has not been accepted as authoritative.
+The time consumed was 24¼ hours.</p>
+
+<p>In 1899, Captain von Sigsfield, Captain Hildebrandt,
+and a companion started from Berlin in a
+wind so strong that it prevented the taking on of an
+adequate load of ballast. They rose into a gale, and
+in two hours were over Breslau, having made the
+distance at a speed of 92 miles per hour. In the
+grasp of the storm they continued their swift journey,
+landing finally high up in the snows of the
+Carpathian Alps in Austria. They were arrested
+by the local authorities as Russian spies, but succeeded
+in gaining their liberty by telegraphing to an
+official more closely in touch with the aeronautics of
+the day.</p>
+
+<p>In 1900 there were several balloon voyages notable
+for their length. Jacques Balsan travelled from
+<span class="pagenum" id="Page_280">280</span>
+<span class="pagenum" id="Page_281">281</span>
+Vincennes to Dantzig, 757 miles; Count de la Vaulx
+journeyed from Vincennes to Poland, 706 miles;
+Jacques Faure from Vincennes to Mamlity, 753
+miles. In a subsequent voyage Jacques Balsan travelled
+from Vincennes to Rodom, in Russia, 843 miles,
+in 27½ hours.</p>
+
+<div class="figcenter">
+<img src="images/i_280.jpg" alt="" />
+<p class="caption">The balloon in which Coxwell and Glaisher made their famous ascent of
+29,000 feet.</p></div>
+
+<p>One of the longest balloon voyages on record in
+point of time consumed is that of Dr. Wegener of the
+Observatory at Lindenberg, in 1905. He remained
+in the air for 52¾ hours.</p>
+
+<p>The longest voyage, as to distance, up to 1910,
+was that of Count de La Vaulx and Count Castillon
+de Saint Victor in 1906, in the balloon “Centaur.”
+This was a comparatively small balloon, having a
+capacity of only 55,000 cubic feet of gas. The start
+was made from Vincennes on October 9th, and the
+landing at Korostischeff, in Russia, on October 11th.
+The air-line distance travelled was 1,193 miles, in
+35¾ hours. The balloon “Centaur” was afterward
+purchased by the Aero Club of America, and has
+made many voyages in this country.</p>
+
+<p>The Federation Aeronautique Internationale, an
+association of the aeronauts of all nations, was
+founded in 1905. One of its functions is an annual
+balloon race for the International Challenge Cup,
+<span class="pagenum" id="Page_282">282</span>
+presented to the association by James Gordon Bennett,
+to be an object for competition until won three
+times by some one competing national club.</p>
+
+<p>The first contest took place in September, 1906,
+and was won by the American competitor, Lieut.
+Frank P. Lahm, with a voyage of 402 miles.</p>
+
+<p>The second contest was from St. Louis, Mo., in
+1907. There were three German, two French, one
+English, and three American competitors. The race
+was won by Oscar Erbslöh, one of the German competitors,
+with an air-line voyage of 872¼ miles, landing
+at Bradley Beach, N. J. Alfred Leblanc, now
+a prominent aviator, was second with a voyage of
+867 miles, made in 44 hours. He also landed in New
+Jersey.</p>
+
+<p>The third race started at Berlin in October, 1908,
+and was won by the Swiss balloon “Helvetia,” piloted
+by Colonel Schaeck, which landed in Norway
+after having been 74 hours in the air, and
+covering a journey of 750 miles. This broke the
+previous duration record made by Dr. Wegener in
+1905.</p>
+
+<p>The fourth contest began on October 3, 1909, from
+Zurich, Switzerland. There were seventeen competing
+balloons, and the race was won by E. W. Mix,
+<span class="pagenum" id="Page_283">283</span>
+representing the Aero Club of America, with a voyage
+of 589 miles.</p>
+
+<p>The fifth contest began at St. Louis, October 17,
+1910. It was won by Alan P. Hawley and Augustus
+Post, with the “America II.” They travelled 1,355
+miles in 46 hours, making a new world’s record for
+distance.</p>
+
+<p>Among other notable voyages may be mentioned
+that of the “Fielding” in a race on July 4, 1908,
+from Chicago. The landing was made at West
+Shefford, Quebec, the distance travelled being 895
+miles.</p>
+
+<p>In November of the same year A. E. Gaudron,
+Captain Maitland, and C. C. Turner, made the longest
+voyage on record from England. They landed at
+Mateki Derevni, in Russia, having travelled 1,117
+miles in 31½ hours. They were driven down to the
+ground by a severe snowstorm.</p>
+
+<p>On December 31, 1908, M. Usuelli, in the balloon
+“Ruwenzori” left the Italian lakes and passed over
+the Alps at a height of 14,750 feet, landing in
+France. This feat was followed a few weeks later&mdash;February
+9, 1909&mdash;by Oscar Erbslöh, who left St.
+Moritz with three passengers, crossing the Alps at an
+altitude of 19,000 feet, and landed at Budapest after
+<span class="pagenum" id="Page_284">284</span>
+<span class="pagenum" id="Page_285">285</span>
+a voyage of 33 hours. Many voyages over and among
+the Alps have been made by Captain Spelterini, the
+Swiss aeronaut, and he has secured some of the most
+remarkable photographs of the mountain scenery in
+passing. In these voyages at such great altitudes it
+is necessary to carry cylinders of oxygen to provide
+a suitable air mixture for breathing. In one of his
+recent voyages Captain Spelterini had the good fortune
+to be carried almost over the summit of Mont
+Blanc. He ascended with three passengers at Chamounix,
+and landed at Lake Maggiore seven hours
+later, having reached the altitude of 18,700 feet, and
+travelled 93 miles.</p>
+
+<div class="figcenter">
+<img src="images/i_284.jpg" alt="" />
+<p class="caption">Photograph of the Alps from a balloon by Captain Spelterini.</p></div>
+
+<p>In the United States there were several balloon
+races during the year 1909, the most important being
+the St. Louis Centennial race, beginning on October
+4th. Ten balloons started. The race was won by
+S. von Phul, who covered the distance of 550 miles
+in 40 hours 40 minutes. Clifford B. Harmon and
+Augustus Post in the balloon “New York” made
+a new duration record for America of 48 hours 26
+minutes. They also reached the highest altitude attained
+by an American balloon&mdash;24,200 feet.</p>
+
+<p>On October 12th, in a race for the Lahm cup, A.
+Holland Forbes and Col. Max Fleischman won.
+<span class="pagenum" id="Page_286">286</span>
+They left St. Louis, Mo., and landed 19 hours and
+15 minutes later at Beach, Va., near Richmond, having
+travelled 697 miles.</p>
+
+<p>In 1910, in the United States, a remarkable race,
+with thirteen competitors, started at Indianapolis.
+This was the elimination race for the International
+race on October 17th. It was won by Alan P. Hawley
+and Augustus Post in the balloon “America II.”
+They crossed the Alleghany Mountains at an elevation
+of about 20,000 feet, and landed at Warrenton,
+Va., after being 44 hours 30 minutes in the air;
+and descended only to escape being carried out over
+Chesapeake Bay.</p>
+
+<p>In recent years the greatest height reached by a
+balloon was attained by the Italian aeronauts Piacenza
+and Mina in the “Albatross,” on August 9,
+1909. They went up from Turin to the altitude of
+30,350 feet. The world’s height record rests with
+Professors Berson and Suring of Berlin, who on
+July 31, 1901, reached 35,500 feet. The record of
+37,000 feet claimed by Glaisher and Coxwell in their
+ascension on September 5, 1862, has been rejected as
+not authentic for several discrepancies in their observations,
+and on the ground that their instruments
+were not of the highest reliability. As they carried
+<span class="pagenum" id="Page_287">287</span>
+no oxygen, and reported that for a time they were
+both unconscious, it is estimated that the highest
+point they could have reached under the conditions
+was less than 31,000 feet.</p>
+
+<p>The greatest speed ever recorded for any balloon
+voyage was that of Captain von Sigsfield and Dr.
+Linke in their fatal journey from Berlin to Antwerp,
+during which the velocity of 125 miles per hour was
+recorded.</p>
+
+<p>Ballooning as a sport has a fascination all its own.
+There is much of the spice of adventure in the fact
+that one’s destiny is quite unknown. Floating with
+the wind, there is no consciousness of motion.
+Though the wind may be travelling at great speed,
+the balloon seems to be in a complete calm. A lady
+passenger, writing of a recent trip, has thus described
+her experience:&mdash;“The world continues slowly to unroll
+itself in ever-varying but ever-beautiful panorama&mdash;patchwork
+fields, shimmering silver streaks,
+toy box churches and houses, and white roads like the
+joints of a jig-saw puzzle. And presently cotton-wool
+billows come creeping up, with purple shadows and
+fleecy outlines and prismatic rainbow effects. Sometimes
+they invade the car, and shroud it for a while
+in clinging warm white wreaths, and anon they fall
+<span class="pagenum" id="Page_288">288</span>
+below and shut out the world with a glorious curtain,
+and we are all alone in perfect silence, in perfect
+peace, and in a realm made for us alone.</p>
+
+<p>“And so the happy, restful hours go smoothly by,
+until the earth has had enough of it, and rising up
+more or less rapidly to invade our solitude, hits the
+bottom of our basket, and we step out, or maybe roll
+out, into every-day existence a hundred miles away.”</p>
+
+<p>The perfect smoothness of motion, the absolute
+quiet, and the absence of distracting apparatus combine
+to render balloon voyaging the most delightful
+mode of transit from place to place. Some of the
+most fascinating bits of descriptive writing are those
+of aeronauts. The following quotation from the report
+of Capt. A. Hildebrandt, of the balloon corps
+of the Prussian army, will show that although his
+expeditions were wholly scientific, he was far from
+indifferent to the sublimer influences of nature by
+which he was often surrounded.</p>
+
+<p>In his account of the journey from Berlin to Markaryd,
+in Sweden, with Professor Berson as a companion
+aeronaut, he says: “The view over Rügen and
+the chalk cliffs of Stubbenkammer and Arkona was
+splendid: the atmosphere was perfectly clear. On
+the horizon we could see the coasts of Sweden and
+<span class="pagenum" id="Page_289">289</span>
+Denmark, looking almost like a thin mist; east and
+west there was nothing but the open sea.</p>
+
+<p>“About 3:15 the balloon was in the middle of the
+Baltic; right in the distance we could just see Rügen
+and Sweden. The setting of the sun at 4 P.M.
+was a truly magnificent spectacle. At a height of
+5,250 feet, in a perfectly clear atmosphere, the effect
+was superb. The blaze of color was dimly reflected
+in the east by streaks of a bluish-green. I have seen
+sunsets over France at heights of 10,000 feet, with
+the Alps, the Juras, and the Vosges Mountains in
+the distance; but this was quite as fine.</p>
+
+<p>“The sunsets seen by the mountaineer or the sailor
+are doubtless, magnificent; but I hardly think the
+spectacle can be finer than that spread out before the
+gaze of the balloonist. The impression is increased
+by the absolute stillness which prevails; no sound
+of any kind is heard.</p>
+
+<div class="figcenter">
+<img src="images/i_290.jpg" alt="" />
+<p class="caption">Landscape as seen from a balloon at an altitude of 3,000 feet.</p></div>
+
+<p>“As soon as the sun went down, it was necessary
+to throw out some ballast, owing to the decrease of
+temperature.... We reached the Swedish coast
+about 5 o’clock, and passed over Trelleborg at a
+height of 2,000 feet. The question then arose
+whether to land, or to continue through the night.
+Although it was well past sunset, there was sufficient
+<span class="pagenum" id="Page_290">290</span>
+<span class="pagenum" id="Page_291">291</span>
+light in consequence of the snow to see our way to
+the ground, and to land quite easily.... However,
+we wanted to do more meteorological work, and it
+was thought that there was still sufficient ballast to
+take us up to a much greater height. We therefore
+proposed to continue for another sixteen hours during
+the night, in spite of the cold.... Malmö was
+therefore passed on the left, and the university town
+of Lund on the right. After this the map was of no
+further use, as it was quite dark and we had no lamp.
+The whole outlook was like a transformation scene.
+Floods of light rose up from Trelleborg, Malmö,
+Copenhagen, Landskrona, Lund, Elsinore, and Helsingborg,
+while the little towns beneath our feet
+sparkled with many lights. We were now at a height
+of more than 10,000 feet, and consequently all these
+places were within sight. The glistening effect of
+the snow was heightened by the blaze which poured
+from the lighthouses along the coasts of Sweden and
+Denmark. The sight was as wonderful as that of the
+sunset, though of a totally different nature.”</p>
+
+<p>Captain Hildebrandt’s account of the end of this
+voyage illustrates the spice of adventure which is
+likely to be encountered when the balloon comes down
+in a strange country. It has its hint also of the hardships
+<span class="pagenum" id="Page_292">292</span>
+for which the venturesome aeronaut has to be
+prepared. He says:&mdash;</p>
+
+<p>“Sooner or later the balloon would have been at
+the mercy of the waves. The valve was opened, and
+the balloon descended through the thick clouds. We
+could see nothing, but the little jerks showed us that
+the guide-rope was touching the ground. In a few
+seconds we saw the ground, and learned that we
+were descending into a forest which enclosed a number
+of small lakes. At once more ballast was thrown
+out, and we skimmed along over the tops of the trees.
+Soon we crossed a big lake, and saw a place that
+seemed suitable for a descent. The valve was then
+opened, both of us gave a tug at the ripping cord,
+and after a few bumps we found ourselves on the
+ground. We had come down in deep snow on the
+side of a wood, about 14 miles from the railway station
+at Markaryd.</p>
+
+<div class="figcenter">
+<img src="images/i_293.jpg" alt="" />
+<p class="caption">Making a landing with the aid of bystanders to pull down upon the trail-rope
+and a holding rope.</p></div>
+
+<p>“We packed up our instruments, and began to
+look out for a cottage; but this is not always an
+easy task in the dead of night in a foreign country.
+However, in a quarter of an hour we found a farm,
+and succeeded in rousing the inmates. A much more
+difficult job was to influence them to open their front
+door to two men who talked some sort of double
+<span class="pagenum" id="Page_293">293</span>
+Dutch, and who suddenly appeared at a farmyard
+miles off the highway in the middle of the night
+and demanded admittance. Berson can talk in six
+languages, but unfortunately Swedish is not one of
+them. He begged in the most humble way for shelter
+... and at the end of three-quarters of an hour
+the farmer opened the door. We showed him some
+<span class="pagenum" id="Page_294">294</span>
+pictures of a balloon we had with us, and then they
+began to understand the situation. We were then received
+with truly Swedish hospitality, and provided
+with supper. They even proposed to let us have their
+beds; but this we naturally declined with many
+thanks.... The yard contained hens, pigs, cows,
+and sheep; but an empty corner was found, which
+was well packed with straw, and served as a couch for
+our tired limbs. We covered ourselves with our great-coats,
+and tried to sleep. But the temperature was
+10° Fahr., and as the place was only an outhouse
+of boards roughly nailed together, and the wind
+whistling through the cracks and crevices, we were
+not sorry when the daylight came.”</p>
+
+<p>Lest the possibility of accident to travellers by
+balloon be judged greater than it really is, it may
+be well to state that records collected in Germany in
+1906 showed that in 2,061 ascents in which 7,570
+persons participated, only 36 were injured&mdash;or but 1
+out of 210. Since that time, while the balloon itself
+has remained practically unchanged, better knowledge
+of atmospheric conditions has aided in creating
+an even more favorable record for recent years.</p>
+
+<p>That the day of ordinary ballooning has not been
+dimmed by the advent of the airship and the aeroplane
+<span class="pagenum" id="Page_295">295</span>
+is evidenced by the recently made estimate that
+not less than 800 spherical balloons are in constant
+use almost daily in one part or another of Christendom.
+And it seems entirely reasonable to predict that
+with a better comprehension of the movements of
+air-currents&mdash;to which special knowledge the scientific
+world is now applying its investigations as never
+before&mdash;they will come a great increase of interest in
+simple ballooning as a recreation.
+<span class="pagenum" id="Page_296">296</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XIV">Chapter XIV.<br />
+
+BALLOONS: THE DIRIGIBLE.</h2>
+
+<blockquote>
+
+<p>Elongation of gas-bag&mdash;Brisson&mdash;Meusnier&mdash;Air-ballonnets&mdash;Scott&mdash;Giffard&mdash;Haenlein&mdash;Tissandier&mdash;Renard
+and Krebs&mdash;Schwartz&mdash;Santos-Dumont&mdash;Von
+Zeppelin&mdash;Roze&mdash;Severo&mdash;Bradsky-Leboun&mdash;The
+Lebaudy dirigible&mdash;Zeppelin II&mdash;Parseval
+I&mdash;Unequal wind pressures&mdash;Zeppelin III&mdash;Nulli
+Secundus&mdash;La Patrie&mdash;Ville-de-Paris&mdash;Zeppelin IV&mdash;Gross
+I&mdash;Parseval II&mdash;Clement-Bayard I&mdash;Ricardoni’s airship&mdash;Gross
+II&mdash;The new Zeppelin II&mdash;La Republique&mdash;The
+German fleet of dirigibles&mdash;Parseval V&mdash;The Deutschland&mdash;The
+Erbslöh&mdash;Gross III&mdash;Zeppelin VI&mdash;The America&mdash;Clement-Bayard
+III&mdash;The Capazza lenticular dirigible.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> dirigible balloon, or airship, is built on the
+same general principles as the ordinary balloon&mdash;that
+is, with the envelope to contain the lifting
+gas, the car to carry the load, and the suspending
+cordage&mdash;but to this is added some form of propelling
+power to enable it to make headway against the
+wind, and a rudder for steering it.</p>
+
+<p>Almost from the very beginning of ballooning,
+some method of directing the balloon to a pre-determined
+goal had been sought by inventors. Drifting
+at the fickle pleasure of the prevailing wind
+<span class="pagenum" id="Page_297">297</span>
+did not accord with man’s desire for authority and
+control.</p>
+
+<p>The first step in this direction was the change
+from the spherical form of the gas-bag to an elongated
+shape, the round form having an inclination to
+turn round and round in the air while floating, and
+having no bow-and-stern structure upon which steering
+devices could operate. The first known proposal
+in this direction was made by Brisson, a French scientist,
+who suggested building the gas-bag in the
+shape of a horizontal cylinder with conical ends, its
+length to be five or six times its diameter. His idea
+for its propulsion was the employment of large-bladed
+oars, but he rightly doubted whether human
+strength would prove sufficient to work these rapidly
+enough to give independent motion to the airship.</p>
+
+<p>About the same time another French inventor had
+actually built a balloon with a gas-bag shaped like
+an egg and placed horizontally with the blunt end
+foremost. The reduction in the resistance of the air
+to this form was so marked that the elongated gas-bag
+quickly displaced the former spherical shape.
+This balloon was held back from travelling at the
+full speed of the wind by the clever device of a rope
+dragging on the ground; and by a sail rigged so as
+<span class="pagenum" id="Page_298">298</span>
+to act on the wind which blew past the retarded
+balloon, the navigator was able to steer it within
+certain limits. It was the first dirigible balloon.</p>
+
+<p>In the same year the brothers Robert, of Paris,
+built an airship for the Duke of Chartres, under the
+direction of General Meusnier, a French officer of
+engineers. It was cylindrical, with hemispherical
+ends, 52 feet long and 32 feet in diameter, and contained
+30,000 cubic feet of gas. The gas-bag was
+made double to prevent the escape of the hydrogen,
+which had proved very troublesome in previous balloons,
+and it was provided with a spherical air balloon
+inside of the gas-bag, which device was expected
+to preserve the form of the balloon unchanged by
+expanding or contracting, according to the rising or
+falling of the airship. When the ascension was made
+on July 6, 1784, the air-balloon stuck fast in the
+neck of the gas-bag, and so prevented the escape of
+gas as the hydrogen expanded in the increasing altitude.
+The gas-bag would have burst had not the
+Duke drawn his sword and slashed a vent for the
+imprisoned gas. The airship came safely to earth.</p>
+
+<p>It was General Meusnier who first suggested the
+interior ballonnet of air to preserve the tense outline
+of the form of the airship, and the elliptical form for
+<span class="pagenum" id="Page_299">299</span>
+the gas-bag was another of his inventions. In the
+building of the airship of the Duke de Chartres he
+made the further suggestion that the space between
+the two envelopes be filled with air, and so connected
+with the air-pumps that it could be inflated or deflated
+at will. For the motive power he designed
+three screw propellers of one blade each, to be turned
+unceasingly by a crew of eighty men.</p>
+
+<p>Meusnier was killed in battle in 1793, and aeronautics
+lost its most able developer at that era.</p>
+
+<div class="figcenter">
+<img src="images/i_299.jpg" alt="" />
+<p class="caption">The Scott airship, showing the forward “pocket” partially drawn in.</p></div>
+
+<p>In 1789, Baron Scott, an officer in the French
+army, devised a fish-shaped airship with two outside
+balloon-shaped “pockets” which could be forcibly
+drawn into the body of the airship to increase its
+density, and thus cause its descent.</p>
+
+<p>It began to be realized that no adequate power existed
+by which balloons could be propelled against
+<span class="pagenum" id="Page_300">300</span>
+even light winds to such a degree that they were
+really controllable, and balloon ascensions came to be
+merely an adjunct of the exhibit of the travelling
+showman. For this reason the early part of the
+nineteenth century seems barren of aeronautical incident
+as compared with the latter part of the preceding
+century.</p>
+
+<p>In 1848, Hugh Bell, an Englishman, built a cylindrical
+airship with convex pointed ends. It was 55
+feet long and 21 feet in diameter. It had a keel-shaped
+framework of tubes to which the long narrow
+car was attached, and there was a screw propeller on
+each side, to be worked by hand, and a rudder to
+steer with. It failed to work.</p>
+
+<p>In 1852, however, a new era opened for the airship.
+Henry Giffard, of Paris, the inventor of the
+world-famed injector for steam boilers, built an elliptical
+gas-bag with cigar-shaped ends, 144 feet long,
+and 40 feet in diameter, having a cubic content of
+88,000 cubic feet. The car was suspended from a
+rod 66 feet long which hung from the net covering
+the gas-bag. It was equipped with a 3-horse-power
+steam engine which turned a two-bladed screw propeller
+11 feet in diameter, at the rate of 110 revolutions
+per minute. Coke was used for fuel. The
+<span class="pagenum" id="Page_301">301</span>
+steering was done with a triangular rudder-sail.
+Upon trial on September 24, 1852, the airship
+proved a success, travelling at the rate of nearly 6
+miles an hour.</p>
+
+<div class="figcenter">
+<img src="images/i_301.jpg" alt="" />
+<p class="caption">The first Giffard dirigible.</p></div>
+
+<p>Giffard built a second airship in 1855, of a much
+more elongated shape&mdash;235 feet long and 33 feet in
+diameter. He used the same engine which propelled
+his first ship. After a successful trial trip, when
+about to land, the gas-bag unaccountably turned up
+on end, allowing the net and car to slide off, and, rising
+slightly in the air, burst. Giffard and his companion
+escaped unhurt.</p>
+
+<p>Giffard afterward built the large captive balloon
+for the London Exhibition in 1868, and the still
+<span class="pagenum" id="Page_302">302</span>
+larger one for the Paris Exposition in 1878. He
+designed a large airship to be fitted with two boilers
+and a powerful steam-engine, but became blind,
+and died in 1882.</p>
+
+<div class="figcenter">
+<img src="images/i_302.jpg" alt="" />
+<p class="caption">The Haenlein airship inflated with coal gas and driven by a gas-engine.</p></div>
+
+<p>In 1865, Paul Haenlein devised a cigar-shaped
+airship to be inflated with coal gas. It was to be
+propelled by a screw at the front to be driven by a
+gas-engine drawing its fuel from the gas in the body
+of the ship. An interior air-bag was to be expanded
+as the gas was consumed, to keep the shape intact.
+A second propeller revolving horizontally was intended
+to raise or lower the ship in the air.
+<span class="pagenum" id="Page_303">303</span></p>
+
+<p>It was not until 1872 that he finally secured the
+building of an airship, at Vienna, after his plans.
+It was 164 feet long, and 30 feet in diameter.
+The form of the gas-bag was that described by the
+keel of a ship rotated around the centre line of its
+deck as an axis. The engine was of the Lenoir type,
+with four horizontal cylinders, developing about 6
+horse-power, and turned a propeller about 15 feet
+in diameter at the rate of 40 revolutions per minute.
+The low lifting power of the coal gas with which it
+was inflated caused it to float quite near the ground.
+With a consumption of 250 cubic feet of gas per
+hour, it travelled at a speed of ten miles an hour.
+The lack of funds seems to have prevented further
+experiments with an invention
+which was at least very promising.</p>
+
+<div class="figcenter">
+<img src="images/i_303.jpg" alt="" />
+<p class="caption">Sketch of the De Lome airship.</p></div>
+
+<p>In the same year a dirigible
+balloon built by Dupuy de
+Lome for use by the French
+Government during the siege
+of Paris, was given a trial.
+It was driven by a screw propeller turned by eight
+men, and although it was 118 feet long, and 49
+feet in diameter, it made as good a speed record
+<span class="pagenum" id="Page_304">304</span>
+as Giffard’s steam-driven airship&mdash;six miles an
+hour.</p>
+
+<div class="figcenter">
+<img src="images/i_304.jpg" alt="" />
+<p class="caption">Car of the Tissandier dirigible; driven by electricity.</p></div>
+
+<p>In 1881, the brothers Albert and Gaston Tissandier
+exhibited at the Electrical Exhibition in Paris
+a model of an electrically driven airship, originally
+designed to establish communication with Paris during
+the siege of the Franco-Prussian War. In 1883,
+the airship built after this model was tried. It was
+92 feet long, and 30 feet at its largest diameter.
+The motive power was a Siemens motor run by 24
+<span class="pagenum" id="Page_305">305</span>
+bichromate cells of 17 lbs. each. At full speed the
+motor made 180 revolutions per minute, developing
+1½ horse-power. The pull was 26 lbs. The propeller
+was 9 feet in diameter, and a speed of a little
+more than 6 miles an hour was attained.</p>
+
+<div class="figcenter">
+<img src="images/i_305.jpg" alt="" />
+<p class="caption">Sketch of the Renard and Krebs airship <i>La France</i>, driven by a storage battery.</p></div>
+
+<p>In 1884, two French army engineers, Renard
+and Krebs, built an airship, the now historic <i>La
+France</i>, with the shape of a submarine torpedo. It
+was 165 feet long and about 27 feet in diameter at
+the largest part. It had a gas content of 66,000
+cubic feet. A 9 horse-power Gramme electric motor
+was installed, driven by a storage battery. This
+operated the screw propeller 20 feet in diameter,
+which was placed at the forward end of the long car.
+The trial was made on the 9th of August, and was
+a complete success. The ship was sailed with the
+wind for about 2½ miles, and then turned about and
+<span class="pagenum" id="Page_306">306</span>
+made its way back against the wind till it stood directly
+over its starting point, and was drawn down
+to the ground by its anchor ropes. The trip of about
+5 miles was made in 23 minutes. In seven voyages
+undertaken the airship was steered back safely to its
+starting point five times.</p>
+
+<p>This first airship which really deserved the name
+marked an era in the development of this type of
+aircraft. In view of its complete success it is astonishing
+that nothing further was done in this line
+in France for fifteen years, when Santos-Dumont began
+his series of record-making flights. Within this
+period, however, the gasoline motor had been adapted
+to the needs of the automobile, and thus a new and
+light-weight engine, suitable in every respect, had
+been placed within the reach of aeronauts.</p>
+
+<p>In the meantime, a new idea had been brought to
+the stage of actual trial. In 1893, in St. Petersburg,
+David Schwartz built a rigid airship, the gas receptacle
+of which was sheet aluminum. It was braced
+by aluminum tubes, but while being inflated the interior
+work was so badly broken that it was abandoned.</p>
+
+<p>Schwartz made a second attempt in Berlin in
+1897. The airship was safely inflated, and managed
+<span class="pagenum" id="Page_307">307</span>
+to hold its position against a wind blowing 17 miles
+an hour, but could not make headway against it.
+After the gas had been withdrawn, and before it
+could be put under shelter, a severe windstorm damaged
+it, and the mob of spectators speedily demolished
+it in the craze for souvenirs of the occasion.</p>
+
+<div class="figcenter">
+<img src="images/i_307.jpg" alt="" />
+<p class="caption">Wreck of the Schwartz aluminum airship, at Berlin, in 1897.</p></div>
+
+<div class="figcenter">
+<img src="images/i_308.jpg" alt="" />
+<blockquote>
+
+<p>The type of the earlier Santos-Dumont dirigibles. This shape showed a tendency to “buckle,” or double
+up in the middle like a jackknife. To avoid this the later Santos-Dumonts were of much larger proportional
+diameter amidships.</p></blockquote>
+</div>
+
+<p>In 1898, the young Brazilian, Santos-Dumont,
+came to Paris imbued with aeronautic zeal, and determined
+to build a dirigible balloon that would surpass
+the former achievements of Giffard and Renard,
+which he felt confident were but hints of what
+might be accomplished by that type of airship. He
+began the construction of the series of dirigible balloons
+which eventually numbered 12, each successive
+one being an improvement on the preceding. He
+<span class="pagenum" id="Page_308">308</span>
+<span class="pagenum" id="Page_309">309</span>
+made use of the air-bag suggested by Meusnier for
+the balloon of the Duke of Chartres in 1784, although
+in an original way, at first using a pneumatic
+pump to inflate it, and later a rotatory fan. Neither
+prevented the gas-bag from “buckling” and coming
+down with consequences more or less serious to the
+airship&mdash;but Santos-Dumont himself always escaped
+injury. His own record of his voyages in his book,
+<i>My Air-Ships</i>, gives a more detailed account of his
+contrivances and inventions than can be permitted
+here. If Santos-Dumont did not greatly surpass his
+predecessors, he is at least to be credited with an enthusiasm
+<span class="pagenum" id="Page_310">310</span>
+which aroused the interest of the whole
+world in the problems of aeronautics; and his later
+achievements in the building and flying of aeroplanes
+give him a unique place in the history of man’s conquest
+of the air.</p>
+
+<div class="figcenter">
+<img src="images/i_309.jpg" alt="" />
+<p class="caption">Type of the later Santos-Dumont’s dirigibles.</p></div>
+
+<p>In 1900, Count von Zeppelin’s great airship, which
+had been building for nearly two years, was ready
+for trial. It had the form of a prism of 24 sides,
+with the ends arching to a blunt point. It was 420
+feet long, and 38 feet in diameter. The structure
+was rigid, of aluminum lattice work, divided into
+17 compartments, each of which had a separate gas-bag
+shaped to fit its compartment. Over all was
+an outer envelope of linen and silk treated with
+pegamoid. A triangular keel of aluminum lattice
+strengthened the whole, and there were two cars of
+aluminum attached to the keel. Each car held a
+16 horse-power Daimler gasoline motor, operating
+two four-bladed screw propellers which were rigidly
+connected with the frame of the ship a little below
+the level of its axis. A sliding weight was run to
+either end of the keel as might be required to depress
+the head or tail, in order to rise or fall in the
+air. The cars were in the shape of boats, and the
+ship was built in a floating shed on the Lake of Constance
+<span class="pagenum" id="Page_311">311</span>
+<span class="pagenum" id="Page_312">312</span>
+near Friedrichshafen. At the trial the airship
+was floated out on the lake, the car-boats resting
+on the water. Several accidents happened, so that
+though the ship got up into the air it could not be
+managed, and was brought down to the water again
+without injury. In a second attempt a speed of
+20 miles an hour was attained. The construction
+was found to be not strong enough for the great
+length of the body, the envelope of the balloon was
+not sufficiently gas tight, and the engines were not
+powerful enough. But few trips were made in it,
+and they were short. The Count set himself to work
+to raise money to build another ship, which he did
+five years later.</p>
+
+<div class="figcenter">
+<img src="images/i_311.jpg" alt="" />
+<p class="caption">View of the Zeppelin I, with portion of the aluminum shell and external fabric removed to show the internal framing and
+separate balloons. In the distance is shown the great balloon shed.</p></div>
+
+<p>In 1901, an inventor named Roze built an airship
+in Colombo, having two gas envelopes with the engines
+and car placed between them. He expected to
+do away with the rolling and pitching of single airships
+by the double form, but the ship did not work
+satisfactorily, ascending to barely 50 feet.</p>
+
+<p>In 1902, Augusto Severo, a Brazilian, arranged
+an airship with the propelling screws at the axis of
+the gas-bag, one at each end of the ship. Instead
+of a rudder, he provided two small propellers to
+work in a vertical plane and swing the ship sideways.
+<span class="pagenum" id="Page_313">313</span>
+Soon after ascending it was noticed that the propellers
+were not working properly, and a few minutes
+later the car was seen to be in flames and the
+balloon exploded. Severo and his companion Sache
+were killed, falling 1,300 feet.</p>
+
+<div class="figcenter">
+<img src="images/i_313a.jpg" alt="" />
+<p class="caption">Sketch of the Severo airship, showing arrangement of the driving propellers
+on the axis of the gas-bag, and the steering propellers.</p></div>
+
+<div class="figcenter">
+<img src="images/i_313b.jpg" alt="" />
+<blockquote>
+
+<p>End view of Severo’s
+airship, showing the
+longitudinal division
+of the gas-bag to allow
+the driving shaft
+of the propellers to
+be placed at the axis
+of the balloon.</p></blockquote>
+</div>
+
+<p>In the same year Baron Bradsky-Leboun
+built an airship with partitions
+in the gas-bag which was
+just large enough to counterbalance
+the weight of the ship and
+its operators. It was lifted or lowered
+by a propeller working horizontally.
+Another propeller drove
+the ship forward. Through some
+lack of stability the car turned
+over, throwing out the two aeronauts, who fell 300
+feet and were instantly killed.
+<span class="pagenum" id="Page_314">314</span></p>
+
+<div class="figcenter">
+<img src="images/i_314.jpg" alt="" />
+<p class="caption">The first Lebaudy airship.</p></div>
+
+<p>In 1902, a dirigible balloon was built for the
+brothers Lebaudy by the engineer Juillot and the
+aeronaut Surcouf. The gas envelope was made
+cigar-shaped and fastened rigidly to a rigid elliptical
+keel-shaped floor 70 feet long and 19 feet wide, made
+of steel tubes&mdash;the object being to prevent rolling
+and pitching. It was provided with both horizontal
+and vertical rudders. A 35 horse-power Daimler-Mercedes
+motor was used to turn two twin-bladed
+screws, each of 9 feet in diameter. Between the
+25th of October, 1902, and the 21st of November,
+<span class="pagenum" id="Page_315">315</span>
+1903, 33 experimental voyages were made, the longest
+being 61 miles in 2 hours and 46 minutes; 38.7
+miles in 1 hour and 41 minutes; 23 miles in 1 hour
+and 36 minutes.</p>
+
+<div class="figcenter">
+<img src="images/i_315.jpg" alt="" />
+<p class="caption">Framing of the floor and keel of the Lebaudy airship.</p></div>
+
+<p>In 1904 this ship was rebuilt. It was lengthened
+to 190 feet and the rear end rounded off. Its capacity
+<span class="pagenum" id="Page_316">316</span>
+was increased to 94,000 cubic feet, and a new
+covering of the yellow calico which had worked so
+well on the first model was used on the new one.
+It was coated with rubber both on the outside and inside.
+The interior air-bag was increased in size to
+17,650 cubic feet, and partitioned into three compartments.
+During 1904 and 1905 30 voyages were
+made, carrying in all 195 passengers.</p>
+
+<div class="figcenter">
+<img src="images/i_316.jpg" alt="" />
+<p class="caption">The car and propellers of the Lebaudy airship.</p></div>
+
+<p>The success of this airship led to a series of trials
+under the direction of the French army, and in all
+of these trials it proved satisfactory. After the 76th
+successful voyage it was retired for the winter of
+1905-6.
+<span class="pagenum" id="Page_317">317</span></p>
+
+<p>In November, 1905, the rebuilt Zeppelin airship
+was put upon trial. While superior to the first one,
+it met with serious accident, and was completely
+wrecked by a windstorm in January, 1906.</p>
+
+<p>In May, 1906, Major von Parseval’s non-rigid
+airship passed through its first trials successfully.
+This airship may be packed into small compass for
+transportation, and is especially adapted for military
+use. In plan it is slightly different from previous
+types, having two air-bags, one in each end
+of the envelope, and the front end is hemispherical
+instead of pointed.</p>
+
+<p>As the airship is designed to force its way through
+the air, instead of floating placidly in it, it is evident
+that it must have a certain tenseness of outline
+in order to retain its shape, and resist being doubled
+up by the resistance it encounters. It is estimated
+that the average velocity of the wind at the elevation
+at which the airship sails is 18 miles per hour. If
+the speed of the ship is to be 20 miles per hour, as
+related to stations on the ground, and if it is obliged
+to sail against the wind, it is plain that the wind
+pressure which it is compelled to meet is 38 miles
+per hour&mdash;a gale of no mean proportions. When the
+large expanse of the great gas-bags is taken into consideration,
+<span class="pagenum" id="Page_318">318</span>
+it is evident that ordinary balloon construction
+is not sufficient.</p>
+
+<p>Attempts have been made to meet the outside pressure
+from the wind and air-resistance by producing
+mechanically a counter-pressure from the inside.
+Air-bags are placed inside the cavity of the gas-bag,
+usually one near each end of the airship, and these
+are inflated by pumping air into them under pressure.
+In this way an outward pressure of as much
+as 7 lbs. to the square foot may be produced, equivalent
+to the resistance of air at a speed (either of the
+wind, or of the airship, or of both combined) of 48
+miles per hour. It is evident, however, that the pressure
+upon the front end of an airship making headway
+against a strong wind will be much greater than
+the pressure at the rear end, or even than that amidships.
+It was this uneven pressure upon the outside
+of the gas-bag that doubled up the first two airships
+of Santos-Dumont, and led him to increase the proportional
+girth at the amidship section in his later
+dirigibles. The great difficulty of adjusting these
+varying pressures warrants the adherence of Count
+von Zeppelin to his design with the rigid structure
+and metallic sheathing.</p>
+
+<p>The loss of the second Zeppelin airship so discouraged
+<span class="pagenum" id="Page_319">319</span>
+<span class="pagenum" id="Page_320">320</span>
+its designer that he decided to withdraw
+from further aeronautical work. But the German
+Government prevailed on him to continue, and by
+October, 1906, he had the Zeppelin III in the air.
+This airship was larger than Zeppelin II in both
+length and diameter, and held 135,000 cubic feet
+more of gas. The motive power was supplied by two
+gasoline motors, each of 85 horse-power. The gas
+envelope had 16 sides, instead of 24, as in the earlier
+ship. At its trial the Zeppelin III proved highly
+successful. It made a trip of 69 miles, with 11 passengers,
+in 2¼ hours&mdash;a speed of about 30 miles an
+hour.</p>
+
+<div class="figcenter">
+<img src="images/i_319.jpg" alt="" />
+<p class="caption">The Zeppelin III backing out of the floating shed at Friedrichshafen. The illustration shows the added fin at the top, the rudders,
+dipping planes, and balancing planes.</p></div>
+
+<p>The German Government now made an offer of
+$500,000 for an airship which would remain continuously
+in the air for 24 hours, and be able to land
+safely. Count von Zeppelin immediately began work
+upon his No. IV, in the effort to meet these requirements,
+in the meantime continuing trips with No.
+III. The most remarkable of these trips was made
+in September, 1907, a journey of 211 miles in 8
+hours.</p>
+
+<p>In October, 1907, the English airship “Nulli Secundus”
+was given its first trial. The gas envelope
+had been made of goldbeater’s skins, which are considered
+<span class="pagenum" id="Page_321">321</span>
+impermeable to the contained gas, but are
+very expensive. This airship was of the non-rigid
+type. It made the trip from Aldershot to London, a
+distance of 50 miles, in 3½ hours&mdash;an apparent speed
+of 14 miles per hour, lacking information as to the
+aid or hindrance of the prevailing wind. Several
+other trials were made, but with small success.</p>
+
+<p>The offer of the German Government had stimulated
+other German builders besides Count von Zeppelin,
+and on October 28, 1907, the Parseval I,
+which had been improved, and the new Gross dirigible,
+competed for the government prize, at Berlin.
+The Parseval kept afloat for 6½ hours, and the Gross
+for 8¼ hours.</p>
+
+<p>Meanwhile, in France, the Lebaudys had been
+building a new airship which was named “La Patrie.”
+It was 197 feet long and 34 feet in diameter.
+In a trial for altitude it was driven to an elevation
+of 4,300 feet. On November 23, 1907, the “Patrie”
+set out from Paris for Verdun, a distance of
+146 miles. The journey was made in 6¾ hours, at
+an average speed of 25 miles per hour, and the fuel
+carried was sufficient to have continued the journey
+50 miles further. Soon after reaching Verdun a
+severe gale tore the airship away from the regiment
+<span class="pagenum" id="Page_322">322</span>
+of soldiers detailed to assist the anchors in holding
+it down, and it disappeared into the clouds. It is
+known to have passed over England, for parts of its
+machinery were picked up at several points, and
+some days later the gas-bag was seen floating in the
+North Sea.</p>
+
+<div class="figcenter">
+<img src="images/i_322.jpg" alt="" />
+<p class="caption">The “Ville-de-Paris” of M. de la Meurthe.</p></div>
+
+<p>Following close upon the ill-fated “Patrie” came
+the “Ville-de-Paris,” a dirigible which had been
+built by Surcouf for M. Henri Deutsch de la
+Meurthe, an eminent patron of aeronautic experiments.
+In size this airship was almost identical with
+the lost “Patrie,” but it was quite different in appearance.
+It did not have the flat framework at the
+bottom of the gas envelope, but was entirely round
+in section, and the long car was suspended below.
+<span class="pagenum" id="Page_323">323</span>
+At the rear the gas-bag was contracted to a cylindrical
+form, and four groups of two ballonnets each
+were attached to act as stabilizers. It was offered
+by M. de la Meurthe to the French Government to
+take the place of the “Patrie” in the army manœuvres
+at Verdun, and on January 15, 1908, made
+the trip thither from Paris in about 7 hours. It
+was found that the ballonnets exerted considerable
+drag upon the ship.</p>
+
+<p>In June, 1908, the great “Zeppelin IV” was
+completed and given its preliminary trials, and on
+July 1 it started on its first long journey. Leaving
+Friedrichshafen, its route was along the northerly
+shore of Lake Constance nearly to Schaffhausen,
+then southward to and around Lake Lucerne, thence
+northward to Zurich, thence eastward to Lake Constance,
+and to its shed at Friedrichshafen. The distance
+traversed was 236 miles, and the time consumed
+12 hours. This voyage without a single mishap
+aroused the greatest enthusiasm among the German
+people. After several short flights, during
+which the King of Württemberg, the Queen, and
+some of the royal princes were passengers, the Zeppelin
+IV set out on August 4 to win the Government
+reward by making the 24-hour flight. Sailing eastward
+<span class="pagenum" id="Page_324">324</span>
+from Friedrichshafen it passed over Basle,
+then turning northward it followed the valley of the
+Rhine, passing over Strasburg and Mannheim, and
+had nearly reached Mayence when a slight accident
+necessitated a landing. Repairs were made, and the
+journey resumed after nightfall. Mayence was
+reached at 11 <small>P. M.</small>, and the return trip begun. When
+passing over Stuttgart, at 6 <small>A. M.</small>, a leak was discovered,
+and a landing was made at Echterdingen, a
+few miles farther on. Here, while repairs were being
+made, a squall struck the airship and bumped
+it heavily on the ground. Some gasoline was spilled,
+in some unknown way, which caught fire, and in a
+few moments the great balloon was totally destroyed.
+It had been in continuous flight 11 hours up to the
+time of the first landing, and altogether 20¾ hours,
+and had travelled 258 miles.</p>
+
+<p>The German people immediately started a public
+subscription to provide Count von Zeppelin with the
+funds needed to build another airship, and in a few
+days the sum of $1,500,000 was raised and turned
+over to the unfortunate inventor. The “Zeppelin
+III” was taken in hand, and lengthened, and more
+powerful engines installed.</p>
+
+<p>The “Gross II” was ready to make its attempt for
+<span class="pagenum" id="Page_325">325</span>
+<span class="pagenum" id="Page_326">326</span>
+the Government prize on September 11, 1908. It
+sailed from Tegel to Magdeburg and back to Tegel,
+a distance of 176 miles, in 13 hours, without
+landing.</p>
+
+<div class="figcenter">
+<img src="images/i_325.jpg" alt="" />
+<p class="caption">The Clement-Bayard dirigible entering its shed.</p></div>
+
+<p>Four days later the “Parseval II” made a trip
+between the same points in 11½ hours, but cut the
+distance travelled down to 157 miles. In October,
+the “Parseval II” was sent up for an altitude test,
+and rose to a height of 5,000 feet above Tegel, hovering
+over the city for upward of an hour.</p>
+
+<p>During 1908, an airship designed by M. Clement,
+the noted motor-car builder, was being constructed
+in France. It made its first voyage on October 29,
+carrying seven passengers from Sartrouville to Paris
+and back, at a speed of from 25 to 30 miles per hour.
+The illustration gives a very good idea of the peculiar
+ballonnets attached to the rear end of the gas
+envelope. These ballonnets open into the large gas-bag,
+and are practically a part of it.</p>
+
+<p>In Italy a remarkable dirigible has been built by
+Captain Ricaldoni, for military purposes. It has
+the form of a fish, blunt forward, and tapering
+straight away to the rear. It has a large finlike surface
+on the under side of the gas-bag toward the
+rear. Its performances show that its efficiency as
+<span class="pagenum" id="Page_327">327</span>
+<span class="pagenum" id="Page_328">328</span>
+compared with its motive power is larger than any
+other dirigible in commission.</p>
+
+<div class="figcenter">
+<img src="images/i_327.jpg" alt="" />
+<p class="caption">Engine of the Clement-Bayard dirigible; 7-cylinder; 55 horse-power; weighing only 155 pounds.</p></div>
+
+<p>In May, 1909, the rebuilt “Zeppelin III,” now rechristened
+“Zeppelin II,” after many successful short
+flights was prepared for the Government trial. On
+May 29, 1909, with a crew of six men, Count von
+Zeppelin started from Friedrichshafen for Berlin,
+360 miles away. The great ship passed over Ulm,
+Nuremburg, Bayreuth, and Leipzig; and here it encountered
+so strong a head wind from the north, that
+it was decided to turn about at Bitterfeld and return
+to Friedrichshafen. The distance travelled had
+been nearly 300 miles in 21 hours. The course followed
+was quite irregular, and took the ship over
+Wurtzburg, and by a wide detour to Heilbron and
+Stuttgart. The supply of gasoline running low, it
+was decided to land at Goeppingen, where more
+could be obtained. It was raining heavily, and
+through some mistake in steering, or some sudden
+veering of the wind, the prow of the great dirigible
+came into collision with a tree upon the hillside.
+The envelope was badly torn, and a part of the aluminum
+inner structure wrecked. However, the mechanics
+on board were able to make such repairs that
+the ship was able to resume the voyage the next day,
+<span class="pagenum" id="Page_329">329</span>
+<span class="pagenum" id="Page_330">330</span>
+and made port without further mishap. The vessel
+having been 38 hours in the air at the time of the
+accident, so much of the Government’s stipulations
+had been complied with. But it had not succeeded
+in landing safely. Nevertheless it was accepted by
+the Government. The entire journey has been variously
+estimated at from 680 to 900 miles, either figure
+being a record for dirigibles.</p>
+
+<div class="figcenter">
+<img src="images/i_329.jpg" alt="" />
+<p class="caption">Accident to the new “Zeppelin II” at Goeppingen. The damage was repaired and the airship continued its voyage the next day.</p></div>
+
+<p>On August 4, the dirigible “Gross II” made a
+voyage from Berlin to Apolda, and returned; a distance
+of 290 miles in 16 hours. This airship also
+was accepted by the German Government and added
+to its fleet.</p>
+
+<p>In August, the Zeppelin II was successfully sailed
+to Berlin, where Count von Zeppelin was welcomed
+by an immense and enthusiastic multitude of his
+countrymen, including the Emperor and the royal
+family.</p>
+
+<p>On September 26, the new French dirigible, “La
+Republique,” built on the model of the successful
+Lebaudy airships, met with an accident while in the
+air. A blade of one of the propellers broke and
+slashed into the envelope. The ship fell from a
+height of 6,000 feet, and its crew of four men lost
+their lives.
+<span class="pagenum" id="Page_331">331</span></p>
+
+<div class="figcenter">
+<img src="images/i_331.jpg" alt="" />
+<p class="caption">View of the damaged Zeppelin from the front, showing the tree against which it collided.
+<span class="pagenum" id="Page_332">332</span></p></div>
+
+<p>On April 22, 1910, a fleet of German dirigibles,
+comprising the “Zeppelin II,” the “Gross II,” and
+the “Parseval I,” sailed from Cologne to Hamburg,
+where they were reviewed by Emperor William. A
+strong wind having arisen, the “Gross II,” which
+is of the semi-rigid type, was deflated, and shipped
+back to Cologne by rail. The non-rigid “Parseval”
+made the return flight in safety. The rigid “Zeppelin
+II” started on the return voyage, but was compelled
+to descend at Limburg, where it was moored.
+The wind increasing, it was forced away, and finally
+was driven to the ground at Weilburg and demolished.</p>
+
+<p>In May, 1910, the “Parseval V,” the smallest
+dirigible so far constructed, being but 90 feet in
+length, was put upon its trial trip. It made a circular
+voyage of 80 miles in 4 hours.</p>
+
+<p>For several months a great Zeppelin passenger
+dirigible had been building by a stock company
+financed by German capital, under the direction of
+the dauntless Count von Zeppelin. It was 490 feet
+long, with a capacity of 666,900 cubic feet. A passenger
+cabin was built with ¼-inch mahogany veneer
+upon a framework of aluminum, the inside being
+decorated with panels of rosewood inlaid with
+<span class="pagenum" id="Page_333">333</span>
+mother-of-pearl. The seats were wicker chairs, and
+the window openings had no glass. It was christened
+the “Deutschland.”</p>
+
+<p>After many days waiting for propitious weather
+the first “air-liner” set sail on June 22, 1910, from
+Friedrichshafen for Düsseldorf, carrying 20 passengers
+who had paid $50 each for their passage. In
+addition there were 13 other persons on board.</p>
+
+<p>The start was made at three o’clock in the morning,
+and the course laid was up the valley of the
+Rhine, as far as Cologne. Düsseldorf was reached at
+three o’clock in the afternoon, the airline distance
+of 300 miles having been covered in 9 hours of actual
+sailing. From Mannheim to Düsseldorf, favored
+by the wind, the great ship reached the speed
+of 50 miles per hour, for this part of the trip, outstripping
+the fastest express trains which consume
+6 hours in the winding track up the valley.</p>
+
+<p>The next morning the “Deutschland” left Düsseldorf
+on an excursion trip, carrying several ladies
+among its passengers. The voyage was in every way
+a great success, and public enthusiasm was widespread.</p>
+
+<p>On June 29, a test trip was decided upon. No
+passengers were taken, but 19 newspaper correspondents
+<span class="pagenum" id="Page_334">334</span>
+were invited guests. The Count had been
+warned of weather disturbances in the neighborhood,
+but he either disregarded them or felt confidence in
+his craft. It was intended that the voyage should
+last four hours, but the airship soon encountered a
+storm, and after 6 hours of futile striving against it,
+the fuel gave out. Caught in an upward draft, the
+“Deutschland” rose to an altitude of over 5,000
+feet, losing considerable gas, and then, entering a
+rainstorm, was heavily laden with moisture. Suddenly,
+without definite reason, it began to fall vertically,
+and in a few moments had crashed into the
+tops of the trees of the Teutoberg forest. No one
+on board received more than slight injury, and all
+alighted safely by means of ladders. The “Deutschland”
+was a wreck, and was taken apart and shipped
+back to Friedrichshafen.</p>
+
+<p>On July 13, another giant passenger airship, designed
+by Oscar Erbslöh, who won the international
+balloon race in 1907 by a voyage from St. Louis to
+Asbury Park, met with fatal disaster. It was sailing
+near Cologne at an altitude of about 2,500 feet
+when it burst, and Erbslöh and his four companions
+were killed in the fall.</p>
+
+<p>On July 28, the “Gross III” left Berlin with the
+<span class="pagenum" id="Page_335">335</span>
+object of beating the long distance record for dirigibles.
+Soon after passing Gotha the airship returned
+to that place, and abandoned the attempt. In 13
+hours a distance of 260 miles had been traversed.</p>
+
+<p>Undismayed by the catastrophes which had destroyed
+his airships almost as fast as he built them,
+Count von Zeppelin had his number VI ready to
+sail on September 3. With a crew of seven and
+twelve passengers he sailed from Baden to Heidelberg&mdash;53
+miles in 65 minutes. It was put into commission
+as an excursion craft, and made several successful
+voyages. On September 14, as it was being
+placed in its shed at the close of a journey, it took
+fire unaccountably, and was destroyed together with
+the shed, a part of the framework only remaining.</p>
+
+<p>On October 15, 1910, the Wellman dirigible
+“America” which had been in preparation for many
+weeks, left Asbury Park in an attempt to cross the
+Atlantic. Its balloon was 228 feet long, with a diameter
+of 52 feet, containing 345,000 cubic feet of
+gas. The car was 156 feet in length, and was arranged
+as a tank in which 1,250 gallons of gasoline
+were carried. A lifeboat was attached underneath
+the car. There were two engines, each of 80 horse-power,
+and an auxiliary motor of 10 horse-power.
+<span class="pagenum" id="Page_336">336</span>
+Sleeping quarters were provided for the crew of six,
+and the balloon was fitted with a wireless telegraph
+system. All went well until off the island of Nantucket,
+where strong north winds were encountered,
+and the dirigible was swept southward toward Bermuda.
+As an aid in keeping the airship at an elevation
+of about 200 feet above the sea, an enlarged
+trail-rope, called the equilibrator, had been constructed
+of cans which were filled with gasoline.
+This appendage weighed 1½ tons, and the lower part
+of it was expected to float upon the sea. In practice
+it was found that the jarring of this equilibrator,
+when the sea became rough, disarranged the machinery,
+so that the propellers would not work, and the
+balloon was compelled to drift with the wind. Toward
+evening of the second day a ship was sighted,
+and the America’s crew were rescued. The airship
+floated away in the gale, and was soon out of sight.</p>
+
+<p>On October 16, a new Clement-Bayard dirigible,
+with seven men on board, left Paris at 7.15 o’clock
+in the morning, and sailed for London. At 1 <small>P. M.</small>
+it circled St. Paul’s Cathedral, and landed at the
+hangar at Wormwood Scrubbs a half hour later.
+The distance of 259 miles (airline) was traversed
+at the rate of 41 miles per hour, and the journey
+<span class="pagenum" id="Page_337">337</span>
+<span class="pagenum" id="Page_338">338</span>
+surpassed in speed any previous journey by any other
+form of conveyance.</p>
+
+<div class="figcenter">
+<img src="images/i_337.jpg" alt="" />
+<p class="small"><i>Copyright by Pictorial News Company.</i></p>
+
+<p class="caption">Wellman dirigible “America” starting for Europe, October 15, 1910.</p>
+</div>
+
+<p>On November 5, 1910, the young Welsh aeronaut,
+Ernest T. Willows, who sailed his small dirigible
+from Cardiff to London in August, made a trip
+from London across the English Channel to Douai,
+France. This is the third time within a month that
+the Channel had been crossed by airships.</p>
+
+<div class="figcenter">
+<img src="images/i_338.jpg" alt="" />
+<blockquote>
+
+<p>Diagram of the Capazza dirigible from the side. <i>A A</i>, stabilizing fins; <i>B</i>, air-ballonnet;
+<i>R</i>, rudder; <i>M M</i>, motors; <i>FS</i>, forward propeller; <i>SS</i>, stern
+propeller.</p></blockquote>
+</div>
+
+<p>Toward the close of 1910, 52 dirigibles were in
+commission or in process of construction. In the
+United States there were 7; in Belgium, 2; in England,
+6; in France, 12; in Germany, 14; in Italy, 5;
+in Russia, 1; in Spain, 1.</p>
+
+<p>The new Capazza dirigible is a decided departure
+from all preceding constructions, and may mark a
+<span class="pagenum" id="Page_339">339</span>
+new era in the navigation of the air. Its gas envelope
+is shaped like a lens, or a lentil, and is arranged
+to sail flatwise with the horizon, thus partaking
+of the aeroplane as well as the balloon type.
+No definite facts concerning its achievements have
+been published.</p>
+
+<div class="figcenter">
+<img src="images/i_339.jpg" alt="" />
+<p class="caption">Capazza dirigible from the front. From above it is an exact circle in outline.
+<span class="pagenum" id="Page_340">340</span></p></div>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XV">Chapter XV.<br />
+
+BALLOONS: HOW TO OPERATE.</h2>
+
+<blockquote>
+
+<p>Preliminary inspection&mdash;Instruments&mdash;Accessories&mdash;Ballast&mdash;Inflating&mdash;Attaching
+the car&mdash;The ascension&mdash;Controls&mdash;Landing&mdash;Some
+things to be considered&mdash;After landing&mdash;Precautions.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> actual operation of a balloon is always entrusted
+to an experienced pilot, or “captain”
+as he is often called, because he is in command, and
+his authority must be recognized instantly whenever
+an order is given. Nevertheless, it is often of great
+importance that every passenger shall understand the
+details of managing the balloon in case of need; and
+a well-informed passenger is greatly to be preferred
+to an ignorant one.</p>
+
+<p>It is ordinarily one of the duties of the captain
+to inspect the balloon thoroughly; to see that there
+are no holes in the gas-bag, that the valve is in perfect
+working order, and particularly that the valve
+rope and the ripping cord are not tangled. He should
+also gather the instruments and equipment to be carried.
+<span class="pagenum" id="Page_341">341</span></p>
+
+<p>The instruments are usually an aneroid barometer,
+and perhaps a mercury barometer, a barograph (recording
+barometer), a psychrometer (recording thermometer),
+a clock, a compass, and an outfit of maps
+of the country over which it is possible that the
+balloon may float. Telegraph blanks, railroad time
+tables, etc., may be found of great service. A camera
+with a supply of plates will be indispensable
+almost, and the camera should be provided with a
+yellow screen for photographing clouds or distant
+objects.</p>
+
+<p>The ballast should be inspected, to be sure that it
+is of dry sand, free from stones; or if water is used
+for ballast, it should have the proper admixture of
+glycerine to prevent freezing.</p>
+
+<p>It is essential that the inflating be properly done,
+and the captain should be competent to direct this
+process in detail, if necessary. What is called the
+“circular method” is the simplest, and is entirely
+satisfactory unless the balloon is being filled with
+pure hydrogen for a very high ascent, in which case
+it will doubtless be in the hands of experts.</p>
+
+<p>When inflating with coal-gas, the supply is usually
+taken from a large pipe adapted for the purpose. At
+a convenient distance from the gas-main the ground
+<span class="pagenum" id="Page_342">342</span>
+is made smooth, and the ground cloths are spread out
+and pegged down to keep them in place.</p>
+
+<p>The folded balloon is laid out on the cloths with
+the neck opening toward the gas-pipe. The balloon
+is then unfolded, and so disposed that the valve will
+be uppermost, and in the centre of a circle embracing
+the upper half of the sphere of the balloon, the
+opening of the neck projecting a few inches beyond
+the rim of the circle. The hose from the gas-main
+may then be connected with the socket in the neck.</p>
+
+<div class="figcenter">
+<img src="images/i_342.jpg" alt="" />
+<p class="caption">Balloon laid out in the circular method, ready for inflation. The valve is seen
+at the centre. The neck is at the right.</p></div>
+
+<p>Having made sure that the ripping cord and the
+valve rope are free from each other, and properly
+<span class="pagenum" id="Page_343">343</span>
+connected with their active parts, and that the valve
+is fastened in place, the net is laid over the whole,
+and spread out symmetrically. A few bags of ballast
+are hooked into the net around the circumference
+of the balloon as it lies, and the assistants distributed
+around it. It should be the duty of one man to hold
+the neck of the balloon, and not to leave it for any
+purpose whatever. The gas may then be turned on,
+and, as the balloon fills, more bags of ballast are
+hung symmetrically around the net; and all are continually
+moved downward as the balloon rises.</p>
+
+<p>Constant watching is necessary during the inflation,
+so that the material of the balloon opens fully
+without creases, and the net preserves its correct position.
+When the inflation is finished the hoop and
+car are to be hooked in place. The car should be
+fitted up and hung with an abundance of ballast.
+Disconnect the gas hose and tie the neck of the balloon
+in such fashion that it may be opened with a
+pull of the cord when the ascent begins.</p>
+
+<p>The ballast is then transferred to the hoop, or ring,
+and the balloon allowed to rise until this is clear of
+the ground. The car is then moved underneath, and
+the ballast moved down from the ring into it. The
+trail-rope should be made fast to the car directly
+<span class="pagenum" id="Page_344">344</span>
+under the ripping panel, the object being to retard
+that side of the balloon in landing, so that the gas
+may escape freely when the panel is torn open, and
+not underneath the balloon, as would happen if the
+balloon came to earth with the ripping panel underneath.</p>
+
+<p>The balloon is now ready to start, and the captain
+and passengers take their places in the car. The neck
+of the balloon is opened, and a glance upward will
+determine if the valve rope hangs freely through it.
+The lower end of this should be tied to one of the
+car ropes. The cord to the ripping panel should be
+tied in a different place, and in such fashion that no
+mistake can be made between them. The assistants
+stand around the edge of the basket, holding it so
+that it shall not rise until the word is given. The
+captain then adjusts the load of ballast, throwing off
+sufficient to allow the balloon to pull upward lightly
+against the men who are holding it. A little more
+ballast is then thrown off, and the word given to let
+go. The trail-rope should be in charge of some one
+who will see that it lifts freely from the ground.</p>
+
+<p>The balloon rises into the air to an altitude where
+a bulk of the higher and therefore lighter air equal
+to the bulk of the balloon has exactly the same weight.
+<span class="pagenum" id="Page_345">345</span>
+<span class="pagenum" id="Page_346">346</span>
+This is ordinarily about 2,000 feet. If the sun
+should be shining the gas in the balloon will be expanded
+by the heat, and some of it will be forced out
+through the neck. This explains the importance of
+the open neck. In some of the early ascensions no
+such provision for the expansion of the gas was made,
+and the balloons burst with disastrous consequences.</p>
+
+<div class="figcenter">
+<img src="images/i_345.jpg" alt="" />
+<p class="caption">Inflating a military balloon. The net is being adjusted smoothly as the balloon rises. The bags of ballast surround the balloon
+ready to be attached as soon as the buoyancy of the gas lifts it from the earth.</p></div>
+
+<p>When some of the gas has been driven out by the
+heat, there is less <i>weight</i> of gas in the balloon, though
+it occupies the same space. It therefore has a tendency
+to rise still higher. On the other hand, if it
+passes into a cloud, or the sun is otherwise obscured,
+the volume of the gas will contract; it will become
+denser, and the balloon will descend. To check the
+descent the load carried by the balloon must be lightened,
+and this is accomplished by throwing out some
+ballast; generally, a few handfuls is enough.</p>
+
+<p>There is always more or less leakage of gas
+through the envelope as well as from the neck, and
+this also lessens the lifting power. To restore the
+balance, more ballast must be thrown out, and in
+this way an approximate level is kept during the
+journey.</p>
+
+<p>When the ballast is nearly exhausted it will be
+necessary to come down, for a comfortable landing
+<span class="pagenum" id="Page_347">347</span>
+cannot be made without the use of ballast. A good
+landing place having been selected, the valve is
+opened, and the balloon brought down within a few
+yards of the ground. The ripping cord is then pulled
+and ballast thrown out so that the basket will touch
+as lightly as possible. Some aeronauts use a small
+anchor or grapnel to assist in making a landing, but
+on a windy day, when the car is liable to do some
+bumping before coming to rest, the grapnel often
+makes matters much worse for the passengers by a
+series of holdings and slippings, and sometimes causes
+a destructive strain upon the balloon.</p>
+
+<p>In making an ascent with a balloon full of gas
+there is certain to be a waste of gas as it expands.
+This expansion is due not only to the heat of the
+sun, but also to the lighter pressure of the air in the
+upper altitudes. It is therefore the custom with
+some aeronauts to ascend with a partially filled balloon,
+allowing the expansion to completely fill it.
+This process is particularly advised if a very high
+altitude is sought. When it is desired to make a
+long voyage it is wise to make the start at twilight,
+and so avoid the heat of the sun. The balloon will
+then float along on an almost unchanging level without
+expenditure of ballast. Rain and even the moisture
+<span class="pagenum" id="Page_348">348</span>
+from clouds will sometimes wet the balloon so
+that it will cause a much greater loss of ballast than
+would have been required to be thrown out to rise
+above the cloud or storm. Such details in the handling
+of a balloon during a voyage will demand the
+skilled judgment of the captain.</p>
+
+<div class="figcenter">
+<img src="images/i_348.jpg" alt="" />
+<p class="caption">A balloon ready for ascent. Notice that the neck is still tied.
+<span class="pagenum" id="Page_349">349</span></p></div>
+
+<p>The trail-rope is a valuable adjunct when the balloon
+is travelling near the ground. The longer the
+part of the trail-rope that is dragging on the ground
+the less weight the balloon is carrying. And at
+night, when it is impossible to tell the direction in
+which one is travelling in any other way, the line
+of the trailing rope will show the direction from
+which the wind is blowing, and hence the drift of the
+balloon.</p>
+
+<p>The care of the balloon and its instruments upon
+landing falls upon the captain, for he is not likely
+to find assistants at hand competent to relieve him
+of any part of the necessary work. The car and the
+ring are first detached. The ropes are laid out free
+and clear, and the valve is unscrewed and taken off.
+The material of the balloon is folded smoothly, gore
+by gore. The ballast bags are emptied. After all
+is bundled up it should be packed in the car, the covering
+cloth bound on with ropes, and definite instructions
+affixed for transportation to the starting-point.</p>
+
+<p>It is apparent that the whole of the gas is lost at
+the end of the journey. The cost of this is the largest
+expense of ballooning. For a small balloon of
+about 50,000 cubic feet, the coal-gas for inflating
+<span class="pagenum" id="Page_350">350</span>
+will cost about $35 to $40. If hydrogen is used, it
+will cost probably ten times as much.</p>
+
+<p>In important voyages it is customary to send up
+pilot balloons, to discover the direction of the wind
+currents at the different levels, so that the level which
+promises the best may be selected before the balloon
+leaves the ground. A study of the weather conditions
+throughout the surrounding country is a wise precaution,
+and no start should be made if a storm is
+imminent. The extent of control possible in ballooning
+being so limited, all risks should be scrupulously
+avoided, both before and during the voyage,
+and nothing left to haphazard.
+<span class="pagenum" id="Page_351">351</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XVI">Chapter XVI.<br />
+
+BALLOONS: HOW TO MAKE.</h2>
+
+<blockquote>
+
+<p>The fabrics used&mdash;Preliminary varnishing&mdash;Varnishes&mdash;Rubberized
+fabrics&mdash;Pegamoid&mdash;Weight of varnish&mdash;Latitudes of
+the balloon&mdash;Calculating gores&mdash;Laying out patterns and
+cutting&mdash;Sewing&mdash;Varnishing&mdash;Drying&mdash;Oiling&mdash;The neck&mdash;The
+valve&mdash;The net&mdash;The basket.</p></blockquote>
+
+<p class="drop"><span class="uppercase">The</span> making of a balloon is almost always placed
+in the hands of a professional balloon-maker.
+But as the use of balloons increases, and their owners
+multiply, it is becoming a matter of importance
+that the most improved methods of making them
+should be known to the intending purchaser, as well
+as to the amateur who wishes to construct his own
+balloon.</p>
+
+<p>The fabric of which the gas envelope is made may
+be either silk, cotton (percale), or linen. It should
+be of a tight, diagonal weave, of uniform and strong
+threads in both warp and woof, unbleached, and
+without dressing, or finish. If it is colored, care
+should be exercised that the dye is one that will not
+<span class="pagenum" id="Page_352">352</span>
+affect injuriously the strength or texture of the fabric.
+Lightness in weight, and great strength (as
+tested by tearing), are the essentials.</p>
+
+<p>The finest German percale weighs about 2½ ounces
+per square yard; Russian percale, 3⅓ ounces, and
+French percale, 3¾ounces, per square yard. The
+white silk used in Russian military balloons weighs
+about the same as German percale, but is very much
+stronger. Pongee silk is a trifle heavier. The silk
+used for sounding balloons is much lighter, weighing
+only a little over one ounce to the square yard.</p>
+
+<p>Goldbeater’s skin and rubber have been used to
+some extent, but the great cost of the former places
+it in reach only of governmental departments, and
+the latter is of use only in small balloons for scientific
+work&mdash;up to about 175 cubic feet capacity.</p>
+
+<p>The fabric is first to be varnished, to fill up the
+pores and render it gas-tight. For this purpose a
+thin linseed-oil varnish has been commonly used.
+To 100 parts of pure linseed-oil are added 4 parts
+of litharge and 1 part of umber, and the mixture is
+heated to about 350° Fahr., for six or seven hours,
+and stirred constantly. After standing a few days
+the clear part is drawn off for use. For the thicker
+varnish used on later coats, the heat should be raised
+<span class="pagenum" id="Page_353">353</span>
+to 450° and kept at about that temperature until it
+becomes thick. This operation is attended with
+much danger of the oil taking fire, and should be
+done only by an experienced varnish-maker.</p>
+
+<p>The only advantages of the linseed-oil varnish are
+its ease of application, and its cheapness. Its drawbacks
+are stickiness&mdash;requiring continual examination
+of the balloon envelope, especially when the
+deflated bag is stored away&mdash;its liability to spontaneous
+combustion, particularly when the varnish is
+new, and its very slow drying qualities, requiring a
+long wait between the coats.</p>
+
+<p>Another varnish made by dissolving rubber in benzine,
+has been largely used. It requires vulcanizing
+after application. It is never sticky, and is always
+soft and pliable. However, the rubber is liable to decomposition
+from the action of the violet ray of light,
+and a balloon so varnished requires the protection
+of an outer yellow covering&mdash;either of paint, or an
+additional yellow fabric. Unfortunately, a single
+sheet of rubberized material is not gas-tight, and it
+is necessary to make the envelope of two, or even
+three, layers of the fabric, thus adding much to the
+weight.</p>
+
+<p>The great gas-bags of the Zeppelin airships are
+<span class="pagenum" id="Page_354">354</span>
+varnished with “Pegamoid,” a patent preparation
+the constituents of which are not known. Its use by
+Count Zeppelin is the highest recommendation possible.</p>
+
+<p>The weight of the varnish adds largely to the
+weight of the envelope. French pongee silk after
+receiving its five coats of linseed-oil varnish, weighs
+8 ounces per square yard. A double bag of percale
+with a layer of vulcanized rubber between, and a
+coating of rubber on the inside, and painted yellow
+on the outside, will weigh 11 ounces per square
+yard. Pegamoid material, which comes ready prepared,
+weighs but about 4 ounces per square yard,
+but is much more costly.</p>
+
+<p>In cutting out the gores of the envelope it is possible
+to waste fully ⅓ of the material unless the
+work is skilfully planned. Taking the width of
+the chosen material as a basis, we must first deduct
+from ¾ of an inch to 1½ inches, in proportion to the
+size of the proposed balloon, for a broad seam and
+the overlapping necessary. Dividing the circumference
+at the largest diameter&mdash;the “equator” of the
+balloon&mdash;by the remaining width of the fabric gives
+the number of gores required. To obtain the breadth
+of each gore at the different “latitudes” (supposing
+<span class="pagenum" id="Page_355">355</span>
+<span class="pagenum" id="Page_356">356</span>
+the globe of the balloon to be divided by parallels
+similar to those of the earth) the following table is
+to be used; 0° representing the equator, and 90° the
+apex of the balloon. The breadth of the gore in inches
+at any latitude is the product of the decimal
+opposite that latitude in the table by the original
+width of the fabric in inches, thus allowing for
+seams.</p>
+
+<div class="figcenter">
+<img src="images/i_355.jpg" alt="" />
+<blockquote>
+
+<p>Finsterwalder’s method of cutting material for a spherical balloon, by which
+over one-fourth of the material, usually wasted in the common method,
+may be saved. It has the further advantage of saving more than half of
+the usual sewing. The balloon is considered as a spherical hexahedron
+(a six-surfaced figure similar to a cube, but with curved sides and edges).
+The circumference of the sphere divided by the width of the material
+gives the unit of measurement. The dimensions of the imagined hexahedron
+may then be determined from the calculated surface and the
+cutting proceed according to the illustration above, which shows five
+breadths to each of the six curved sides. The illustration shows the seams
+of the balloon made after the Finsterwalder method, when looking down
+upon it from above.</p></blockquote>
+</div>
+
+<h3><span class="smcap">Table for Calculating Shape of Gores for Spherical
+Balloons</span></h3>
+
+<table>
+  <tr>
+    <td class="tdr">0°</td>
+    <td class="decimal"><span class="right">1</span>.<span class="left">000</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">3°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">998</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">6°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">994</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">9°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">988</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">12°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">978</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">15°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">966</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">18°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">951</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">21°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">934</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">24°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">913</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">27°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">891</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">30°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">866</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">33°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">839</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">36°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">809</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">39°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">777</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">42°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">743</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">45°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">707</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">48°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">669</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">51°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">629</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">54°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">588</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">57°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">544</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">60°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">500</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">63°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">454</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">66°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">407</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">69°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">358</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">72°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">309</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">75°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">259</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">78°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">208</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">81°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">156</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">84°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">104</span></td>
+  </tr>
+  <tr>
+    <td class="tdr">87°</td>
+    <td class="decimal"><span class="right">0</span>.<span class="left">052⅓</span></td>
+  </tr>
+</table>
+
+<p>In practice, the shape of the gore is calculated by
+the above table, and plotted out on a heavy pasteboard,
+generally in two sections for convenience in
+handling. The board is cut to the plotted shape and
+used as the pattern for every gore. In large establishments
+all the gores are cut at once by a machine.</p>
+
+<p>The raw edges are hemmed, and folded into one
+<span class="pagenum" id="Page_357">357</span>
+another to give a flat seam, and are then sewn together
+“through and through,” in twos and threes:
+afterward these sections are sewn together. Puckering
+must be scrupulously avoided. In the case of
+rubberized material, the thread holes should be
+smeared with rubber solution, and narrow strips of
+the fabric cemented over the seams with the same
+substance.</p>
+
+<p>Varnishing is the next process, the gores being
+treated in turn. Half of the envelope is varnished
+first, and allowed to dry in a well-ventilated place
+out of reach of the sun’s rays. The other half is
+varnished when the first is dry. A framework which
+holds half of the balloon in the shape of a bell is
+usually employed. In case of haste, the balloon may
+be blown up with air, but this must be constantly renewed
+to be of any service.</p>
+
+<p>The first step in varnishing is to get one side (the
+outer, or the inner) coated with a varnish thin
+enough to penetrate the material: then turn the envelope
+the other side out and give that a coat of the
+thin varnish. Next, after all is thoroughly dry, give
+the outer side a coat of thick varnish closing all pores.
+When this is dry give the inner side a similar coat.
+Finally, after drying thoroughly, give both sides a
+<span class="pagenum" id="Page_358">358</span>
+coat of olive oil to prevent stickiness. The amount
+of varnish required is, for the first coat 1½ times the
+weight of the envelope, and for the second coat ½ the
+weight&mdash;of the thin varnish. For the thick coat on
+the outer side ⅓ of the weight of the envelope, and
+on the inner side about half as much. For the olive-oil
+coat, about ⅛ of the weight of the envelope will be
+needed. These figures are approximate, some material
+requiring more, some less; and a wasteful
+workman will cause a greater difference.</p>
+
+<p>The neck of the balloon (also called the tail) is in
+form a cylindrical tube of the fabric, sewn to an
+opening in the bottom of the balloon, which has been
+strengthened by an extra ring of fabric to support
+it. The lower end of the tube, called the mouth, is
+sewn to a wooden ring, which stiffens it. The size
+of the neck is dependent upon the size of the balloon.
+Its diameter is determined by finding the cube of
+one-half the diameter of the balloon, and dividing it
+by 1,000. In length, the neck should be at least
+four times its diameter.</p>
+
+<p>The apex of the balloon envelope is fitted with a
+large valve to permit the escape of gas when it is desired
+that the balloon shall descend. The door of
+the valve is made to open inward into the envelope,
+<span class="pagenum" id="Page_359">359</span>
+and is pulled open by the valve-cord which passes
+through the neck of the balloon into the basket,
+or car. This valve is called the manœuvring valve,
+and there are many different designs equally efficient.
+As they may be had ready made, it is best
+for the amateur, unless he is a machinist, to purchase
+one. The main point to see to is that the seat
+of the valve is of soft pliable rubber, and that the
+door of the valve presses a comparatively sharp edge
+of metal or wood so firmly upon the seat as to indent
+it; and the springs of the valve should be strong
+enough to hold it evenly to its place.</p>
+
+<p>The making of the net of the balloon is another
+part of the work which must be delegated to professionals.
+The material point is that the net distributes
+the weight evenly over the surface of the upper
+hemisphere of the envelope. The strength of the
+cordage is an item which must be carefully tested.
+Different samples of the same material show such
+wide variations in strength that nothing but an actual
+test will determine. In general, however, it may
+be said that China-grass cordage is four times as
+strong as hemp cordage, and silk cordage is ten times
+as strong as hemp&mdash;for the same size cords.</p>
+
+<p>The meshes of the net should be small, allowing
+<span class="pagenum" id="Page_360">360</span>
+the use of a small cord. Large cords mean large
+knots, and these wear seriously upon the balloon envelope,
+and are very likely to cause leaks. In large
+meshes, also, the envelope puffs out between the cords
+and becomes somewhat stretched, opening pores
+through which much gas is lost by diffusion.</p>
+
+<p>The “star,” or centre of the net at the apex of the
+balloon, must be fastened immovably to the rim of
+the valve. The suspension cords begin at from 30°
+to 45° below the equator of the envelope, and are
+looped through rings in what are called “goose-necks.”
+These allow a measure of sliding motion
+to the cordage as the basket sways in the wind.</p>
+
+<p>For protecting the net against rotting from frequent
+wetting, it is recommended to saturate it thoroughly
+with a solution of acetate of soda, drying immediately.
+Paraffin is sometimes used with more or
+less success, but tarring should be avoided, as it materially
+weakens the cordage. Oil or grease are even
+worse.</p>
+
+<p>At the bottom of the net proper the few large cords
+into which the many small cords have been merged
+are attached to the ring of the balloon. This is
+either of steel or of several layers of wood well bound
+together. The ropes supporting the basket are also
+<span class="pagenum" id="Page_361">361</span>
+<span class="pagenum" id="Page_362">362</span>
+fastened to this ring, and from it hang the trail-rope
+and the holding ropes.</p>
+
+<div class="figcenter">
+<img src="images/i_361.jpg" alt="" />
+<blockquote>
+
+<p>Sketch showing the diamond mesh of balloon cordage and the method of distributing
+the rings for the goose-necks; also the merging of netting cords
+into the suspension cords which support the car. The principal knots
+used in tying balloon nets are shown on the right.</p></blockquote>
+</div>
+
+<p>The basket is also to be made by a professional,
+as upon its workmanship may depend the lives of its
+occupants, though every other feature of the balloon
+be faultless. It must be light, and still very strong
+to carry its load and withstand severe bumping. It
+should be from 3 to 4 feet deep, with a floor space
+of 4 feet by 5 feet. It is usually made of willow and
+rattan woven substantially together. The ropes supporting
+the car are passed through the bottom and
+woven in with it. Buffers are woven on to the outside,
+and the inside is padded. The seats are small
+baskets in which is stored the equipment. With the
+completion of these the balloon is ready for its furnishings
+and equipment, which come under the direction
+of the pilot, or captain, as detailed in the preceding
+chapter.
+<span class="pagenum" id="Page_363">363</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XVII">Chapter XVII.<br />
+
+MILITARY AERONAUTICS.</h2>
+
+<blockquote>
+
+<p>The pioneer Meusnier&mdash;L’Entreprenant&mdash;First aerostiers&mdash;First
+aerial warship&mdash;Bombardment by balloons&mdash;Free balloons in
+observations&mdash;Ordering artillery from balloon&mdash;The postal
+balloons of Paris&mdash;Compressed hydrogen&mdash;National experiments&mdash;Bomb
+dropping&mdash;Falling explosives&mdash;Widespread
+activity in gathering fleets&mdash;Controversies&mdash;Range of vision&mdash;Reassuring
+outlook.</p></blockquote>
+
+<p class="drop"><span class="uppercase">Almost</span> from the beginning of success in traversing
+the air the great possibilities of all
+forms of aircraft as aids in warfare have been
+recognized by military authorities, and, as has so
+often been the case with other inventions by non-military
+minds, the practically unlimited funds at
+the disposal of national war departments have been
+available for the development of the balloon at first,
+then the airship, and now of the aeroplane.</p>
+
+<p>The Montgolfiers had scarcely proved the possibility
+of rising into the air, in 1783, before General
+Meusnier was busily engaged in inventing improvements
+in their balloon with the expressed purpose of
+making it of service to his army, and before he was
+<span class="pagenum" id="Page_364">364</span>
+killed in battle he had secured the appointment of
+a commission to test the improved balloon as to its
+efficiency in war. The report of the committee being
+favorable, a balloon corps was formed in April, 1794,
+and the balloon <i>L’Entreprenant</i> was used during the
+battle of Fleurus, on June 26th, by Meusnier’s successor,
+General Jourdan, less than a year after Meusnier’s
+death. In 1795 this balloon was used in the
+battle of Mayence. In both instances it was employed
+for observation only.</p>
+
+<p>But when the French entered Moscow, they found
+there, and captured, a balloon laden with 1,000
+pounds of gunpowder which was intended to have
+been used against them.</p>
+
+<p>In 1796 two other balloons were used by the
+French army then in front of Andernach and Ehrenbreitstein,
+and in 1798 the 1st Company of Aerostiers
+was sent to Egypt, and operated at the battle
+of the Nile, and later at Cairo. In the year following,
+this balloon corps was disbanded.</p>
+
+<p>In 1812 Russia secured the services of a German
+balloon builder named Leppich, or Leppig, to build
+a war balloon. It had the form of a fish, and was
+so large that the inflation required five days, but the
+construction of the framework was faulty, and some
+<span class="pagenum" id="Page_365">365</span>
+<span class="pagenum" id="Page_366">366</span>
+important parts gave way during inflation, and the
+airship never left the ground. As it was intended
+that this balloon should be dirigible and supplied
+with explosives, and take an active part in attacks
+on enemies, it may be regarded as the first aerial
+warship.</p>
+
+<div class="figcenter">
+<img src="images/i_365.jpg" alt="" />
+<p class="caption">A military dirigible making a tour of observation.</p></div>
+
+<p>In 1849, however, the first actual employment of
+the balloon in warfare took place. Austria was engaged
+in the bombardment of Venice, and the range
+of the besieging batteries was not great enough to
+permit shells to be dropped into the city. The engineers
+formed a balloon detachment, and made a
+number of Montgolfiers out of paper. These were of
+a size sufficient to carry bombs weighing 30 pounds
+for half an hour before coming down. These war
+balloons were taken to the windward side of the city,
+and after a pilot balloon had been floated over the
+point where the bombs were to fall, and the time
+consumed in the flight ascertained, the fuses of the
+bombs were set for the same time, and the war balloons
+were released. The actual damage done by the
+dropping of these bombs was not great, but the moral
+effect upon the people of the city was enormous. The
+balloon detachment changed its position as the wind
+changed, and many shells were exploded in the heart
+<span class="pagenum" id="Page_367">367</span>
+of the city, one of them in the market place. But
+the destruction wrought was insignificant as compared
+with that usually resulting from cannonading.
+As these little Montgolfiers were sent up unmanned,
+perhaps they are not strictly entitled to be dignified
+by the name of war balloon, being only what in this
+day would be called aerial bombs.</p>
+
+<p>The next use of the balloon in warfare was by
+Napoleon III, in 1859. He sent up Lieutenant
+Godard, formerly a manufacturer of balloons, and
+Nadar, the balloonist, at Castiglione. It was a tour
+of observation only, and Godard made the important
+discovery that the inhabitants were gathering their
+flocks of domestic animals and choking the roads
+with them, to oppose the advance of the French.</p>
+
+<p>The first military use of balloons in the United
+States was at the time of the Civil War. Within
+a month after the war broke out, Professor T. S. C.
+Lowe, of Washington, put himself and his balloon
+at the command of President Lincoln, and on June
+18, 1861, he sent to the President a telegram from
+the balloon&mdash;the first record of the kind in history.</p>
+
+<p>After the defeat at Manassas, on July 24, 1861,
+Professor Lowe made a free ascent, and discovered
+the true position of the Confederates, and proved
+<span class="pagenum" id="Page_368">368</span>
+the falsity of rumors of their advance. The organization
+of a regular balloon corps followed, and it
+was attached to McClellan’s army, and used in reconnoitering
+before Yorktown. The balloons were
+operated under heavy artillery fire, but were not
+injured.</p>
+
+<div class="figcenter">
+<img src="images/i_368.jpg" alt="" />
+<p class="caption">A small captive military balloon fitted for observation. A cylinder of compressed
+hydrogen to replace leakage is seen at F.
+<span class="pagenum" id="Page_369">369</span></p></div>
+
+<p>On May 24th, for the first time in history, a general
+officer&mdash;in this case, General Stoneman&mdash;directed
+the fire of artillery at a hidden enemy from a balloon.</p>
+
+<p>Later in the month balloons were used at Chickahominy,
+and again at Fair Oaks and Richmond, being
+towed about by locomotives. On the retreat from
+before Richmond, McClellan’s balloons and gas generators
+were captured and destroyed.</p>
+
+<p>In 1869, during the siege of a fort at Wakamatzu
+by the Imperial Japanese troops, the besieged sent
+up a man-carrying kite. After making observations,
+the officer ascended again with explosives, with which
+he attempted to disperse the besieging army, but
+without success.</p>
+
+<p>During the siege of Paris, in 1870, there were
+several experienced balloonists shut up in the city,
+and the six balloons at hand were quickly repaired
+and put to use by the army for carrying dispatches
+and mail beyond the besieging lines. The first trips
+were made by the professional aeronauts, but, as they
+could not return, there was soon a scarcity of pilots.
+Sailors, and acrobats from the Hippodrome, were
+pressed into the service, and before the siege was
+raised 64 of these postal balloons had been dispatched.
+Fifty-seven out of the 64 landed safely on French
+<span class="pagenum" id="Page_370">370</span>
+territory, and fulfilled their mission; 4 were captured
+by the Germans; 1 floated to Norway; 1 was
+lost, with its crew of two sailors, who faithfully
+dropped their dispatches on the rocks near the Lizard
+as they were swept out to sea; and 1 landed on
+the islet Hoedic, in the Atlantic. In all, 164 persons
+left Paris in these balloons, always at night,
+and there were carried a total of 9 tons of dispatches
+and 3,000,000 letters. At first dogs were carried
+to bring back replies, but none ever returned. Then
+carrier pigeons were used successfully. Replies were
+set in type and printed. These printed sheets were
+<span class="pagenum" id="Page_371">371</span>
+reduced by photography so that 16 folio pages of
+print, containing 32,000 words, were reduced to a
+space of 2 inches by 1¼ inches on the thinnest of
+gelatine film. Twenty of these films were packed
+in a quill, and constituted the load for each pigeon.
+When received in Paris, the films were enlarged by
+means of a magic lantern, copied, and delivered to
+the persons addressed.</p>
+
+<div class="figcenter">
+<img src="images/i_370.jpg" alt="" />
+<blockquote>
+
+<p>Spherical canister of compressed hydrogen for use in inflating military balloons.
+A large number of these canisters may be tapped at the same time and the
+inflation proceed rapidly; a large balloon being filled in two hours.</p></blockquote>
+</div>
+
+<p>In more recent times the French used balloons at
+Tonkin, in 1884; the English, in Africa, in 1885;
+the Italians, in Abyssinia, in 1888; and the United
+States, at Santiago, in 1898. During the Boer War,
+in 1900, balloons were used by the British for directing
+artillery fire, and one was shot to pieces by
+well-aimed Boer cannon. At Port Arthur, both the
+Japanese and the Russians used balloons and man-carrying
+kites for observation. The most recent use
+is that by Spain, in her campaign against the Moors,
+in 1909.</p>
+
+<p>The introduction of compressed hydrogen in compact
+cylinders, which are easily transported, has simplified
+the problem of inflating balloons in the field,
+and of restoring gas lost by leakage.</p>
+
+<p>The advent of the dirigible has engaged the active
+attention of the war departments of all the civilized
+<span class="pagenum" id="Page_372">372</span>
+nations, and experiments are constantly progressing,
+in many instances in secret. It is a fact at once
+significant and interesting, as marking the rapidity
+of the march of improvement, that the German Government
+has lately refused to buy the newest Zeppelin
+dirigible, on the ground that it is built of aluminum,
+which is out of date since the discovery of
+its lighter alloys.</p>
+
+<div class="figcenter">
+<img src="images/i_372.jpg" alt="" />
+<p class="caption">The German military non-rigid dirigible Parseval II. It survived the storm
+which wrecked the Zeppelin II in April, 1910, and reached its shed at
+Cologne in safety.</p></div>
+
+<p>Practically all the armies are being provided with
+fleets of aeroplanes, ostensibly for use in scouting.
+But there have been many contests by aviators in
+“bomb-dropping” which have at least proved that
+it is possible to drop explosives from an aeroplane
+with a great degree of accuracy. The favorite target
+<span class="pagenum" id="Page_373">373</span>
+<span class="pagenum" id="Page_374">374</span>
+in these contests has been the life-sized outline of
+a battleship.</p>
+
+<div class="figcenter">
+<img src="images/i_373.jpg" alt="" />
+<p class="caption">The German military Zeppelin dirigible, which took part in the manœuvres at Hamburg in April, 1910,
+and was wrecked by a high wind at Weilburg on the return journey to Cologne.</p></div>
+
+<p>Glenn Curtiss, after his trip down the Hudson
+from Albany, declared that he could have dropped
+a large enough torpedo upon the Poughkeepsie
+Bridge to have wrecked it. His subsequent feats
+in dropping “bombs,” represented by oranges, have
+given weight to his claims.</p>
+
+<p>By some writers it is asserted that the successful
+navigation of the air will guarantee universal peace;
+that war with aircraft will be so destructive that
+the whole world will rise against its horrors. Against
+a fleet of flying machines dropping explosives into
+the heart of great cities there can be no adequate
+defence.</p>
+
+<p>On the other hand, Mr. Hudson Maxim declares
+that the exploding of the limited quantities of dynamite
+that can be carried on the present types of
+aeroplanes, on the decks of warships would not do
+any vital damage. He also says that many tons of
+dynamite might be exploded in Madison Square,
+New York City, with no more serious results than
+the blowing out of the windows of the adjacent buildings
+as the air within rushed out to fill the void
+caused by the uprush of air heated by the explosion.
+<span class="pagenum" id="Page_375">375</span></p>
+
+<div class="figcenter">
+<img src="images/i_375.jpg" alt="" />
+<p class="caption">The Lebaudy airship “La Patrie.” As compared with the first Lebaudy, it shows the rounded stern with
+stabilizing planes, and the long fin beneath, with rudder and dipping planes.
+<span class="pagenum" id="Page_376">376</span></p></div>
+
+<p>As yet, the only experience that may be instanced
+is that of the Russo-Japanese War, where cast-iron
+shells, weighing 448 lbs., containing 28 lbs. of powder,
+were fired from a high angle into Port Arthur,
+and did but little damage.</p>
+
+<p>In 1899 the Hague Conference passed a resolution
+prohibiting the use of aircraft to discharge projectiles
+or explosives, and limited their use in war to observation.
+Germany, France, and Italy withheld
+consent upon the proposition.</p>
+
+<p>In general, undefended places are regarded as exempt
+from attack by bombardment of any kind.</p>
+
+<p>Nevertheless, there are straws which show how
+the wind is blowing. German citizens and clubs
+which purchase a type of airship approved by the
+War Office of the German Empire are to receive a
+substantial subsidy, with the understanding that in
+case of war the aircraft is to be at the disposal of
+the Government. Under this plan it is expected that
+the German Government will control a large fleet of
+ships of the air without being obliged to own them.</p>
+
+<p>And, in France, funds were raised recently, by
+popular subscription, sufficient to provide the nation
+with a fleet of fourteen airships (dirigibles) and
+thirty aeroplanes. These are already being built,
+<span class="pagenum" id="Page_377">377</span>
+and it will not be long before France will have the
+largest air-fleet afloat.</p>
+
+<p>The results of the German manœuvres with a fleet
+of four dirigibles in a night attack upon strong fortresses
+have been kept a profound secret, as if of
+great value to the War Office.</p>
+
+<p>In the United States the Signal Corps has been
+active in operating the Baldwin dirigible and the
+Wright aeroplanes owned by the Government. To
+the latter, wireless telegraphic apparatus has been
+attached and is operated successfully when the machines
+are in flight. In addition, the United States
+Aeronautical Reserve has been formed, with a large
+membership of prominent amateur and professional
+aviators.</p>
+
+<p>Some military experts, however, assert that the
+dirigible is hopelessly outclassed for warfare by the
+aeroplane, which can operate in winds in which the
+dirigible dare not venture, and can soar so high above
+any altitude that the dirigible can reach as to easily
+destroy it. Another argument used against the availability
+of the dirigible as a war-vessel is, that if it
+were launched on a wind which carried it over the
+enemy’s country, it might not be able to return at
+sufficient speed to escape destruction by high-firing
+<span class="pagenum" id="Page_378">378</span>
+guns, even if its limited fuel capacity did not force
+a landing.</p>
+
+<p>Even the observation value of the aircraft is in
+some dispute. The following table is quoted as giving
+the ranges possible to an observer in the air:</p>
+
+<table>
+  <tr>
+    <th>Altitude in feet.</th>
+    <th colspan="2">Distance of horizon.</th>
+  </tr>
+  <tr>
+    <td class="tdr">500</td>
+    <td class="tdc">30</td>
+    <td class="tdc">miles.</td>
+  </tr>
+  <tr>
+    <td class="tdr">1,000</td>
+    <td class="tdc">42</td>
+    <td class="tdc">“</td>
+  </tr>
+  <tr>
+    <td class="tdr">2,000</td>
+    <td class="tdc">59</td>
+    <td class="tdc">“</td>
+  </tr>
+  <tr>
+    <td class="tdr">3,000</td>
+    <td class="tdc">72</td>
+    <td class="tdc">“</td>
+  </tr>
+  <tr>
+    <td class="tdr">4,000</td>
+    <td class="tdc">84</td>
+    <td class="tdc">“</td>
+  </tr>
+  <tr>
+    <td class="tdr">5,000</td>
+    <td class="tdc">93</td>
+    <td class="tdc">“</td>
+  </tr>
+</table>
+
+<p>As a matter of fact, the moisture ordinarily in
+the air effectually limits the range of both natural
+vision and the use of the camera for photographing
+objects on the ground. The usual limit of practical
+range of the best telescope is eight miles.</p>
+
+<p>All things considered, however, it is to be expected
+that the experimenting by army and navy officers all
+over the world will lead to such improvement and
+invention in the art of navigating the air as will
+develop its benevolent, rather than its malevolent,
+possibilities&mdash;“a consummation devoutly to be
+wished.”
+<span class="pagenum" id="Page_379">379</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XVIII">Chapter XVIII.<br />
+
+BIOGRAPHIES OF PROMINENT AERONAUTS.</h2>
+
+<blockquote>
+
+<p>The Wright Brothers&mdash;Santos-Dumont&mdash;Louis Bleriot&mdash;Gabriel
+Voisin&mdash;Leon Delagrange&mdash;Henri Farman&mdash;Robert
+Esnault-Pelterie&mdash;Count von Zeppelin&mdash;Glenn H. Curtiss&mdash;Charles
+K. Hamilton&mdash;Hubert Latham&mdash;Alfred Leblanc&mdash;Claude
+Grahame-White&mdash;Louis Paulhan&mdash;Clifford B.
+Harmon&mdash;Walter Brookins&mdash;John B. Moisant&mdash;J. Armstrong
+Drexel&mdash;Ralph Johnstone.</p></blockquote>
+
+<p class="drop"><span class="uppercase">On</span> January 1, 1909, it would have been a brief
+task to write a few biographical notes about
+the “prominent” aviators. At that date there were
+but five who had made flights exceeding ten minutes
+in duration&mdash;the Wright brothers, Farman, Delagrange,
+and Bleriot. At the close of 1910 the roll of
+aviators who have distinguished themselves by winning
+prizes or breaking previous records has increased
+to more than 100, and the number of qualified pilots
+of flying machines now numbers over 300. The impossibility
+of giving even a mention of the notable
+airmen in this chapter is apparent, and the few whose
+names have been selected are those who have more
+<span class="pagenum" id="Page_380">380</span>
+recently in our own country come into larger public
+notice, and those of the pioneers whose names will
+never lose their first prominence.</p>
+
+<h3>THE WRIGHT BROTHERS.</h3>
+
+<p>The Wright Brothers have so systematically
+linked their individual personalities in all their work,
+in private no less than in public, that the brief life
+story to be told here is but one for them both. In
+fact, until Wilbur went to France in 1908, and
+Orville to Washington, the nearest approach to a
+separation is illustrated by a historic remark of
+Wilbur’s to an acquaintance in Dayton, one afternoon:
+“Orville flew 21 miles yesterday; I am going
+to beat that to-day.” And he did&mdash;by 3 miles.</p>
+
+<p>Their early life in their home town of Dayton,
+Ohio, was unmarked by significant incident. They
+were interested in bicycles, and at length went into
+the business of repairing and selling these machines.</p>
+
+<p>Their attention seems to have been strongly turned
+to the subject of human flight by the death of Lilienthal
+in August, 1896, at which time the press published
+some of the results of his experiments. A
+magazine article by Octave Chanute, himself an experimenter
+with gliders, led to correspondence with
+<span class="pagenum" id="Page_381">381</span>
+him, and the Wrights began a series of similar investigations
+with models of their own building.</p>
+
+<p>By 1900 they had succeeded in flying a large glider
+by running with a string, as with a kite, and in the
+following year they had made some flights on their
+gliders, of which they had several of differing types.
+For two years the Wrights studied and tested and
+disproved nearly every formula laid down by scientific
+works for the relations of gravity to air, and
+finally gave themselves up to discovering by actual
+trial what the true conditions were, and to the improvement
+of their gliders accordingly. Meanwhile
+they continued their constant personal practice in
+the air.</p>
+
+<p>The most of this experimental work was done at
+Kitty Hawk, N. C.; for the reason that there the
+winds blow more uniformly than at any other place
+in the United States, and the great sand dunes there
+gave the Wrights the needed elevation from which
+to leap into the wind with their gliders. Consequently,
+when at last they were ready to try a machine
+driven by a motor, it was at this secluded spot that
+the first flights ever made by man with a heavier-than-air
+machine took place. On December 17, 1903,
+their first machine left the ground under its own
+<span class="pagenum" id="Page_382">382</span>
+<span class="pagenum" id="Page_383">383</span>
+power, and remained in the air for twelve seconds.
+From this time on progress was even slower than
+before, on account of the complications added by the
+motive power; but by the time another year had
+passed they were making flights which lasted five
+minutes, and had their machine in such control that
+they could fly in a circle and make a safe landing
+within a few feet of the spot designated.</p>
+
+<div class="figcenter">
+<img src="images/i_382.jpg" alt="" />
+<p class="caption">Turpin, Taylor, Orville Wright, Wilbur Wright, Brookins, and Johnstone discussing the merits of the Wright
+machine.</p></div>
+
+<p>On the 5th of October, 1905, Wilbur Wright made
+his historic flight of 24 miles at Dayton, Ohio, beating
+the record of Orville, made the day before, of
+21 miles. The average speed of these flights was 38
+miles an hour. No contention as to the priority of the
+device known as wing-warping can ever set aside the
+fact that these long practical flights were made more
+than a year before any other man had flown 500 feet,
+or had remained in the air half a minute, with a
+heavier-than-air machine driven by power.</p>
+
+<p>The Wrights are now at the head of one of the
+largest aeroplane manufactories in the world, and
+devote the larger part of their time to research work
+in the line of the navigation of the air.
+<span class="pagenum" id="Page_384">384</span></p>
+
+<h3>ALBERTO SANTOS-DUMONT.</h3>
+
+<p><span class="smcap">Alberto Santos-Dumont</span> was born in Brazil in
+1877. When but a lad he became intensely interested
+in aeronautics, having been aroused by witnessing
+the ascension at a show of an ordinary hot-air
+balloon. Within the next few years he had made
+several trips to Paris, and in 1897 made his first
+ascent in a balloon with the balloon builder Machuron,
+the partner of the famous Lachambre.</p>
+
+<p>In 1898 he began the construction of his notable
+series of dirigibles, which eventually reached twelve
+in number. With his No. 6 he won the $20,000 prize
+offered by M. Deutsch (de la Meurthe) for the first
+trip from the Paris Aero Club’s grounds to and
+around the Eiffel Tower in 30 minutes or less. The
+distance was nearly 7 miles. It is characteristic of
+M. Santos-Dumont that he should give $15,000 of
+the prize to relieve distress among the poor of Paris,
+and the remainder to his mechanicians who had built
+the balloon.</p>
+
+<p>His smallest dirigible was the No. 9, which held
+7,770 cubic feet of gas; the largest was the No. 10,
+which held 80,000 cubic feet.</p>
+
+<p>In 1905, when Bleriot, Voisin, and their comrades
+<span class="pagenum" id="Page_385">385</span>
+were striving to accomplish flight with machines heavier
+than air, Santos-Dumont turned his genius upon
+the same problem, and on August 14, 1906, he made
+his first flight with a cellular biplane driven by a 24
+horse-power motor. On November 13th of the same
+year he flew 720 feet with the same machine. These
+were the first flights of heavier-than-air machines in
+Europe, and the first public flights anywhere. Later
+he turned to the monoplane type, and with “La
+Demoiselle” added new laurels to those already won
+with his dirigibles.</p>
+
+<h3>LOUIS BLERIOT.</h3>
+
+<p><span class="smcap">Louis Bleriot</span>, designer and builder of the celebrated
+Bleriot monoplanes, and himself a pilot of the
+first rank, was born in Cambrai, France, in 1872.
+He graduated from a noted technical school, and soon
+attached himself to the group of young men&mdash;all under
+thirty years of age&mdash;who were experimenting
+with gliders in the effort to fly. His attempts at first
+were with the flapping-wing contrivances, but he
+soon gave these up as a failure, and devoted his energy
+to the automobile industry; and the excellent
+Bleriot acetylene headlight testifies to his constructive
+ability in that field.
+<span class="pagenum" id="Page_386">386</span></p>
+
+<p>Attracted by the experiments of M. Ernest Archdeacon
+he joined his following, and with Gabriel
+Voisin engaged in building gliders of the biplane
+type. By 1907 he had turned wholly to the monoplane
+idea, and in April of that year made his first
+leap into the air with a power-driven monoplane.
+By September he had so improved his machine that
+he was able to fly 600 feet, and in June, 1908, he
+broke the record for monoplanes by flying nearly a
+mile. Again and again he beat his own records, and
+at length the whole civilized world was thrilled by
+his triumphant flight across the British Channel on
+July 25, 1909.</p>
+
+<p>The Bleriot machines hold nearly all the speed
+records, and many of those in other lines of achievement,
+and M. Bleriot enjoys the double honor of
+being an eminently successful manufacturer as well
+as a dauntless aviator of heroic rank.</p>
+
+<h3>GABRIEL VOISIN.</h3>
+
+<p><span class="smcap">Gabriel Voisin</span>, the elder of the two Voisin brothers,
+was born in 1879 at Belleville-sur-Saone, near
+the city of Lyons, France. He was educated as an
+architect, but early became interested in aeronautics,
+and engaged in gliding, stimulated by the achievements
+<span class="pagenum" id="Page_387">387</span>
+of Pilcher, in England, and Captain Ferber,
+in his own country. He assisted M. Archdeacon in
+his experiments on the Seine, often riding the gliders
+which were towed by the swift motor boats.</p>
+
+<p>In 1906 he associated himself with his brother in
+the business of manufacturing biplane machines, and
+in March, 1907, he himself made the first long flight
+with a power-driven machine in Europe. This aeroplane
+was built for his friend Delagrange, and was
+one in which the latter was soon breaking records
+and winning prizes. The second machine was for
+Farman, who made the Voisin biplane famous by
+winning the Deutsch-Archdeacon prize of $10,000
+for making a flight of 1,093 yards in a circle.</p>
+
+<p>The Voisin biplane is distinctive in structure, and
+is accounted one of the leading aeroplanes of the
+present day.</p>
+
+<h3>LEON DELAGRANGE.</h3>
+
+<p><span class="smcap">Leon Delagrange</span> was born at Orleans, France,
+in 1873. He entered the School of Arts as a student
+in sculpture, about the same time that Henri Farman
+went there to study painting, and Gabriel Voisin,
+architecture. He exhibited at the Salon, and
+won several medals. In 1905, he took up aeronautics,
+assisted at the experiments of M. Archdeacon.
+<span class="pagenum" id="Page_388">388</span>
+His first aeroplane was built by Voisin, and he made
+his first flight at Issy, March 14, 1907. Less than
+a month later&mdash;on April 11&mdash;he made a new record
+for duration of flight, remaining in the air for 9
+minutes and 15 seconds&mdash;twice as long as the previous
+record made by Farman.</p>
+
+<div class="figcenter">
+<img src="images/i_388.jpg" alt="" />
+<p class="caption">Leblanc, Bleriot, and Delagrange,
+(from left to right) in aviation dress, standing in front of the Bleriot machine
+which crossed the English Channel.
+<span class="pagenum" id="Page_389">389</span></p></div>
+
+<p>At Rheims, in 1909, he appeared with a Bleriot
+monoplane, and continued to fly with that type of
+machine until his death. At Doncaster, England,
+he made the world record for speed up to that time,
+travelling at the rate of 49.9 miles per hour. He
+was killed at Bordeaux, France, in January, 1910,
+by the fall of his machine.</p>
+
+<h3>HENRI FARMAN.</h3>
+
+<p><span class="smcap">Henri Farman</span>, justly regarded as the most prominent
+figure in the aviation world today, was born
+in France in 1873. His father was an Englishman.</p>
+
+<p>While a mere boy he became locally famous as a
+bicycle racer, and later achieved a wider fame as a
+fearless and skillful driver in automobile races. In
+1902 he won the Paris-Vienna race.</p>
+
+<p>In September, 1907, he made his first attempt to
+fly, using the second biplane built by his friend Gabriel
+Voisin, and in the following year he won with
+it the Deutsch-Archdeacon prize of $10,000. He
+then built a machine after his own ideas, which more
+resembles the Wright machine than the Voisin, and
+with it he has won many prizes, and made many
+world records. Demands for machines, and for
+teaching the art of handling them, have poured in
+<span class="pagenum" id="Page_390">390</span>
+upon him, necessitating a continual increase of manufacturing
+facilities until it may safely be said that
+he has the largest plant for building flying machines
+in the world, turning out the largest number of machines,
+and through his school for aviators is instructing
+a larger number of pupils annually than
+any other similar establishment.</p>
+
+<h3>ROBERT ESNAULT-PELTERIE.</h3>
+
+<p><span class="smcap">Robert Esnault-Pelterie</span> was born in 1880,
+and educated in the city of Paris. He early showed
+a mechanical turn of mind, and was interested particularly
+in scientific studies. He became an enthusiast
+in matters aeronautic, and devoted himself
+to the construction of gasoline engines suitable for
+aviation purposes. After satisfying his ideal in this
+direction with the now famous “R-E-P” motor, he
+designed a new type of flying machine which is
+known as the “R-E-P monoplane.” His first flights
+were made at Buc in October, 1907, and while they
+were short, they proved the possibility of steering a
+flying machine so that it would describe a curved
+line&mdash;at that time a considerable achievement among
+European aviators. In April, 1908, he flew for ¾
+<span class="pagenum" id="Page_391">391</span>
+of a mile, and reached a height of 100 feet. This
+feat eclipsed all previous records for monoplanes.</p>
+
+<p>His fame, however, rests upon his motors, which
+are quite original in design and construction.</p>
+
+<h3>COUNT FERDINAND VON ZEPPELIN.</h3>
+
+<p><span class="smcap">Count Ferdinand von Zeppelin</span> was born in
+1838, on the shores of the Lake Constance, where
+his great airships have had their initial trials.</p>
+
+<p>It is an interesting fact that Count von Zeppelin
+made his first balloon ascension in a war-balloon attached
+to the army corps commanded by his friend,
+Carl Schurz, during the Civil War.</p>
+
+<p>It was only after years of absorbing study of all
+that human knowledge could contribute that Count
+von Zeppelin decided upon the type of dirigible which
+bears his name. Under the patronage of the King
+of Würtemberg he began his first airship, having
+previously built an immense floating shed, which,
+swinging by a cable, always had its doors facing away
+from the wind.</p>
+
+<p>The successful flights of the series of magnificent
+Zeppelin airships have been marvellous in an age
+crowded with wonders. And the misfortune which
+has followed close upon their superb achievements
+<span class="pagenum" id="Page_392">392</span>
+with complete destruction would long ago have undone
+a man of less energy and courage than the
+dauntless Count. It should be borne in mind, however,
+that of the hundreds of passengers carried in
+his ships of the air, all have come to land safely&mdash;a
+record that it would be difficult to match with any
+other form of travel. The accidents which have destroyed
+the Zeppelins have never happened in the
+air, excepting only the wrecking of the <i>Deutschland</i>
+by a thunderstorm.</p>
+
+<p>The indefatigable Count is now constructing another
+airship with the new alloy, electron, instead
+of aluminum. He estimates that 5,000 pounds’
+weight can be saved in this way.</p>
+
+<h3>CAPTAIN THOMAS S. BALDWIN.</h3>
+
+<p><span class="smcap">Captain Thomas S. Baldwin</span>, balloonist and
+aviator, was born in Mississippi in 1855. His first
+aeronautical experience was as a parachute rider from
+a balloon in the air. He invented the parachute he
+used, and received for it a gold medal from the Balloon
+Society of Great Britain. Exhibiting this parachute,
+Captain Baldwin made an extensive tour of
+the civilized world.</p>
+
+<p>In 1892 he built his first airship, a combination
+<span class="pagenum" id="Page_393">393</span>
+of a balloon, a screw propeller, and a bicycle, the last
+to furnish the motive power. It was not until 1902,
+when be installed an automobile engine in his airship,
+that he succeeded in making it sail. It was not
+yet dirigible, however; but after two years of devising
+and experimenting, he sailed away from Oakland,
+Cal., on August 2, 1904, against the wind, and after
+a short voyage, turned and came back to his balloon-shed.
+From this time on he made several successful
+dirigibles, and in 1908 he met all the requirements
+of the United States Government for a military dirigible,
+and sold to it the only dirigible it possesses.</p>
+
+<p>He became interested in the experiments of Curtiss
+and McCurdy at Hammondsport, in 1908, and aided
+in building the remarkable series of biplanes with
+which record flights were made. The newer design,
+known as the Baldwin biplane, is unique in the pivoted
+balancing plane set upright above the upper
+plane, a device entirely distinct from the warping or
+other manipulation of horizontal surfaces for the purpose
+of restoring lateral balance.</p>
+
+<h3>GLENN HAMMOND CURTISS.</h3>
+
+<p><span class="smcap">Glenn Hammond Curtiss</span> was born at Hammondsport,
+N. Y., on the shore of Lake Keuka, in
+<span class="pagenum" id="Page_394">394</span>
+1878. From boyhood he was a competitor and winner
+in all sorts of races where speed was the supreme
+test. By nature a mechanic, he became noted for his
+ingenious contrivances in this line, and built a series
+of extremely fast motor-cycles, with one of which he
+made the record of one mile in 26⅖ seconds, which
+still stands as the fastest mile ever made by man with
+any form of mechanism.</p>
+
+<p>Through the purchasing of one of his light engines
+by Captain Baldwin for his dirigible, Curtiss
+became interested in aeronautical matters, and soon
+built a glider with which he sailed down from the
+Hammondsport hills. The combination of his motor
+and the glider was the next step, and on July 4, 1908,
+he flew 1½ miles with the <i>June Bug</i>, winning the
+<i>Scientific American</i> trophy.</p>
+
+<p>Learning that the United States was not to be represented
+at the Rheims meet in August, 1909, he
+hastily built a biplane and went there. He won the
+first prize for the course of 30 kilometres (18.6
+miles), second prize for the course of 10 kilometres,
+the James Gordon Bennett cup, and the tenth prize
+in the contest for distance. From Rheims he went
+to Brescia, Italy, and there won the first prize for
+speed. In all these contests he was matching his
+<span class="pagenum" id="Page_395">395</span>
+biplane against monoplanes which were acknowledged
+to be a faster type than the biplane.</p>
+
+<p>On May 29, 1910, Mr. Curtiss made the first stated
+aeroplane tour to take place in this country, travelling
+from Albany to New York City, 137 miles, with
+but one stop for fuel. With this flight he won a
+prize of $10,000.</p>
+
+<p>He has made many other notable flights and stands
+in the foremost rank of the active aviators. At the
+same time he is busily engaged in the manufacture
+of the Curtiss biplane and the Curtiss engine, both
+staple productions in their line.</p>
+
+<h3>CHARLES KEENEY HAMILTON.</h3>
+
+<p><span class="smcap">Charles Keeney Hamilton</span> is justly regarded
+as one of the most skilful of aviators. He was born
+in Connecticut in 1881, and showed his “bent” by
+making distressing, and often disastrous, leaps from
+high places with the family umbrella for a parachute.</p>
+
+<p>In 1904 he worked with Mr. Israel Ludlow, who
+at that time was experimenting with gliders of his
+own construction, and when Mr. Ludlow began towing
+them behind automobiles, Hamilton rode on the
+gliders and steered them. Later he became interested
+<span class="pagenum" id="Page_396">396</span>
+in ballooning, and made a tour of Japan with
+a small dirigible.</p>
+
+<div class="figcenter">
+<img src="images/i_396.jpg" alt="" />
+<p class="caption">Hamilton and Latham.</p></div>
+
+<p>He early became famous in the aviation world by
+his spectacular glides from a great height. He has
+said that the first of these was unintentional, but his
+motor having stopped suddenly while he was high
+in the air, he had only the other alternative of falling
+<span class="pagenum" id="Page_397">397</span>
+vertically. The sensation of the swift gliding
+having pleased him, he does it frequently “for the
+fun of it.” These glides are made at so steep an
+angle that they have gained the distinctive name,
+“Hamilton dives.”</p>
+
+<p>Hamilton came most prominently before the public
+at large with his flight from Governor’s Island to
+Philadelphia and back, on June 13, 1910. Following
+close upon Curtiss’s flight from Albany to New
+York, it was not only a record-breaking achievement,
+but helped to establish in this country the value of
+the aeroplane as a vehicle for place-to-place journeyings.</p>
+
+<h3>HUBERT LATHAM.</h3>
+
+<p><span class="smcap">Hubert Latham</span>, the famous Antoinette pilot, is
+a graduate of Oxford. His father was a naturalized
+Frenchman.</p>
+
+<p>His first aeronautical experience was as companion
+to his cousin, Jacques Faure, the balloonist, on his
+famous trip from London to Paris in 6½ hours, the
+fastest time ever made between the two places until
+the Clement-Bayard dirigible surpassed it by a few
+minutes on October 16, 1910.</p>
+
+<p>The Antoinette monoplane with which M. Latham
+<span class="pagenum" id="Page_398">398</span>
+has identified himself began with the ingenious engine
+of Levavasseur, which was speedily made use
+of for aeroplanes by Santos-Dumont, Bleriot, and
+Farman. Levavasseur also had ideas about aeroplanes,
+and persuaded some capitalists to back him
+in the enterprise. When it was done, no one could
+be found to fly it. Here M. Latham, a lieutenant of
+miners and sappers in the French army, stepped into
+the breach, and has made a name for himself and
+for the Antoinette machine in the forefront of the
+progress of aviation.</p>
+
+<p>After winning several contests he set out, on July
+19, 1909, to cross the British Channel. After flying
+about half the distance he fell into the sea. Six
+days later Bleriot made the crossing successfully,
+and Latham made a second attempt on July 27th,
+and this time got within a mile of the Dover coast
+before he again came down in the water.</p>
+
+<p>He has shown unsurpassed daring and skill in
+flying in gales blowing at 40 miles per hour, a record
+which few other aviators have cared to rival.</p>
+
+<h3>ALFRED LEBLANC.</h3>
+
+<p><span class="smcap">Alfred Leblanc</span>, the champion cross-country flier
+of the world, was born in France in 1879. By profession
+<span class="pagenum" id="Page_399">399</span>
+he is a metallurgist. A friend of Bleriot,
+he became interested in monoplane flying, the
+more readily because he was already a skilled balloonist.</p>
+
+<p>At the time Bleriot made his historic flight across
+the British Channel, Leblanc preceded him, and,
+standing on the Dover shore, signalled Bleriot where
+to strike the land.</p>
+
+<p>He organized Bleriot’s school for aviators at Pau,
+and became its director. Its excellence is exhibited
+in the quality of its pupils; among them Chavez,
+Morane, and Aubrun.</p>
+
+<p>The achievement through which Leblanc is most
+widely known is his winning of the 489-mile race
+over the northern part of France in August, 1910,
+and with the victory the prize of $20,000 offered.</p>
+
+<h3>CLAUDE GRAHAME-WHITE.</h3>
+
+<p><span class="smcap">Claude Grahame-White</span>, the most famous of
+British aviators, learned to fly in France, under the
+tutelage of M. Bleriot, Having accomplished so
+much, he went to Mourmelon, the location of Farman’s
+establishment, and made himself equally proficient
+on the Farman biplane. While in France he
+taught many pupils, among them Armstrong Drexel.
+<span class="pagenum" id="Page_400">400</span>
+Returning to England, he opened a school for English
+aviators.</p>
+
+<p>He came into prominent public notice in his contest
+with Paulhan in the race from London to Manchester,
+and although Paulhan won the prize,
+Grahame-White received a full share of glory for
+his plucky persistence against discouraging mishaps.</p>
+
+<p>At the Boston-Harvard meet, in September, 1910,
+Grahame-White carried off nearly all the prizes, and
+in addition won for himself a large measure of personal
+popularity.</p>
+
+<p>On October 14th he flew from the Benning Race
+Track 6 miles away, over the Potomac River, around
+the dome of the Capitol, the Washington Monument,
+and over the course of Pennsylvania Avenue, up to
+the State, War, and Navy Department building,
+alighting accurately with his 40-foot biplane in the
+60-foot street. Having ended his “call,” he mounted
+his machine and rose skilfully into the air and returned
+to his starting point.</p>
+
+<p>At the Belmont Park meet, in October, Grahame-White
+captured the international speed prize with
+his 100-horse-power Bleriot monoplane, and finished
+second in the race around the Statue of Liberty,
+being beaten by only 43 seconds.
+<span class="pagenum" id="Page_401">401</span></p>
+
+<h3>LOUIS PAULHAN.</h3>
+
+<p><span class="smcap">Louis Paulhan</span> was, in January, 1909, a mechanic
+in Mourmelon, France, earning the good
+wages in that country of $15 per week. He became
+an aviator, making his first flight on July 10, 1909,
+of 1¼ miles. Five days later he flew over 40 miles,
+remaining in the air 1 hour 17 minutes, and rising
+to an altitude of 357 feet, then the world’s record.
+He flew constantly in public through the remainder
+of 1909, winning many prizes and breaking and
+making records.</p>
+
+<p>In January, 1910, he was the most prominent aviator
+at the Los Angeles meet, and there made a new
+world’s record for altitude, 4,166 feet.</p>
+
+<p>Within the 13 months and 3 weeks (up to October
+1, 1910) that he has been flying, he has won
+over $100,000 in prizes, besides receiving many
+handsome fees for other flights and for instruction
+to pupils.</p>
+
+<h3>CLIFFORD B. HARMON.</h3>
+
+<p><span class="smcap">Clifford B. Harmon</span> has the double distinction
+of being not only the foremost amateur aviator of
+America, but his feats have also at times excelled
+those of the professional airmen. On July 2, 1910,
+<span class="pagenum" id="Page_402">402</span>
+Mr. Harmon made a continuous flight of more than
+2 hours, breaking all American records, and this he
+held for several months.</p>
+
+<p>Mr. Harmon’s first experience in the air was as
+a balloonist, and in this capacity he held the duration
+record of 48 hours 26 minutes for a year. On
+this same voyage, at the St. Louis Centennial, he
+made a new record in America for altitude attained,
+24,400 feet.</p>
+
+<p>At the Los Angeles aviation meet, in January,
+1910, where he went with his balloon <i>New York</i>, he
+met Paulhan, and became his pupil. At that meet
+Paulhan made a new world’s record for altitude with
+a Farman biplane, and this machine Mr. Harmon
+bought, and brought to Mineola, L. I., where he
+practised assiduously, crowning his minor achievements
+by flying from there across Long Island Sound
+to Greenwich, Conn.</p>
+
+<p>At the Boston-Harvard aviation meet, in September,
+1910, Mr. Harmon won every prize offered to
+amateur contestants.</p>
+
+<h3>WALTER BROOKINS.</h3>
+
+<p><span class="smcap">Walter Brookins</span> is one of the youngest of noted
+aviators. He was born in Dayton, Ohio, in 1890,
+<span class="pagenum" id="Page_403">403</span>
+and went to school to Miss Katherine Wright, sister
+of the Wright brothers. Young Walter was greatly
+interested in the experiments made by the Wrights,
+and Orville one day promised him that when he grew
+up they would build a flying machine for him.
+Brookins appeared at Dayton in the early part of
+1910, after several years’ absence, during which he
+had grown up, and demanded the promised flying
+machine. The Wrights met the demand, and developed
+Brookins into one of the most successful American
+aviators.</p>
+
+<p>Brookins’s first leap into prominence was at the
+Indianapolis meet, in June, 1910, where he made a
+new world’s record for altitude, 4,803 feet. This
+being beaten soon after in Europe, by J. Armstrong
+Drexel, with 6,600 feet, Brookins attempted, at Atlantic
+City, in September, to excel Drexel’s record,
+and rose to a height of 6,175 feet, being forced to
+come down by the missing of his motor.</p>
+
+<p>On September 29, 1910, he left Chicago for
+Springfield, Ill. He made two stops on the way
+for repairs and fuel, and reached Springfield in 7
+hours 9 minutes elapsed time. His actual time in
+the air was 5 hours 47 minutes. The air-line distance
+between the two cities is 187 miles, but as
+<span class="pagenum" id="Page_404">404</span>
+Brookins flew in the face of a wind blowing 10 miles
+an hour, he actually travelled 250 miles. During
+the journey Brookins made a new cross-country record
+for America in a continuous flight for 2 hours
+38 minutes.</p>
+
+<h3>JOHN B. MOISANT.</h3>
+
+<p><span class="smcap">John B. Moisant</span> is an architect of Chicago, born
+there of Spanish parentage in 1883. Becoming interested
+in aviation, he went to France in 1909, and
+began the construction of two aeroplanes, one of them
+entirely of metal. He started to learn to fly on a
+Bleriot machine, and one day took one of his mechanicians
+aboard and started for London. The mechanician
+had never before been up in an aeroplane.
+After battling with storms and repairing consequent
+accidents to his machine, Moisant landed his passenger
+in London three weeks after the start. It was
+the first trip between the two cities for an aeroplane
+carrying a passenger, and although Moisant failed
+to win the prize which had been offered for such a
+feat, he received a great ovation, and a special medal
+was struck for him.</p>
+
+<p>At the Belmont Park meet, in October, 1910,
+Moisant, after wrecking his own machine in a gale,
+<span class="pagenum" id="Page_405">405</span>
+climbed into Leblanc’s Bleriot, which had been secured
+for him but a few minutes before, and made
+the trip around the Statue of Liberty in New York
+Bay and returned to the Park in 34 minutes 38 seconds.
+As the distance is over 34 miles, the speed was
+nearly a mile a minute. This feat won for him, and
+for America, the grand prize of the meet&mdash;$10,000.</p>
+
+<h3>J. ARMSTRONG DREXEL.</h3>
+
+<p><span class="smcap">J. Armstrong Drexel</span> is a native of Philadelphia.
+He was taught to fly a Bleriot machine at
+Pau by Grahame-White, and he has frequently surpassed
+his instructor in contests where both took part.
+At the English meets in 1910 he won many of the
+prizes, being excelled in this respect only by Leon
+Morane.</p>
+
+<p>At Lanark, Scotland, he established a new world’s
+record for altitude, 6,600 feet. At the Belmont Park
+meet he passed his former record with an altitude
+of 7,185 feet, making this the American record,
+though it had been excelled in Europe. At Philadelphia,
+November 23, 1910, he reached an altitude
+of 9,970 feet, according to the recording barometer
+he carried, thus making a new world’s record. This
+record was disputed by the Aero Club, and it may
+<span class="pagenum" id="Page_406">406</span>
+be reduced. A millionaire, he flies for sheer love of
+the sport.</p>
+
+<h3>RALPH JOHNSTONE.</h3>
+
+<p><span class="smcap">Ralph Johnstone</span> was born in Kansas City, Mo.,
+in 1880. He became an expert bicycle rider, and
+travelled extensively in many countries giving exhibitions
+of trick bicycle riding, including the feat
+known as “looping the loop.” He joined the staff
+of the Wright Brothers’ aviators in April, 1910, and
+speedily became one of the most skilful aeroplane
+operators.</p>
+
+<p>He made a specialty of altitude flying, breaking
+his former records day after day, and finally, at the
+International Aviation Meet at Belmont Park, L. I.,
+in October, 1910, he made a new world’s altitude
+record of 9,714 feet, surpassing the previous record
+of 9,121 feet made by Wynmalen at Mourmelon,
+on October 1st.</p>
+
+<p>Johnstone was instantly killed at Denver, Col.,
+on November 14, 1910, by a fall with his machine
+owing to the breaking of one of the wings at a
+height of 800 feet.
+<span class="pagenum" id="Page_407">407</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XIX">Chapter XIX.<br />
+
+CHRONICLE OF AVIATION ACHIEVEMENTS.</h2>
+
+<p class="drop"><span class="uppercase">How</span> feeble the start, and how wondrously rapid
+the growth of the art of flying! Nothing can
+better convey a full idea of its beginnings and its
+progress than the recorded facts as given below.
+And these facts show beyond dispute that the credit
+of laying the foundation for every accomplishment
+in the entire record must be largely due to the men
+whose names stand alone for years as the only aeroplanists
+in the world&mdash;the Wright Brothers.</p>
+
+<p>After the first flight on December 17, 1903, the
+Wrights worked steadily toward improving their machines,
+and gaining a higher degree of the art of
+balancing, without which even the most perfect machines
+would be useless. Most of their experimenting
+having been done in secret, the open record of
+their results from time to time is very meagre. It
+may be noted, however, that for nearly three years
+no one else made any records at all.
+<span class="pagenum" id="Page_408">408</span></p>
+
+<p>The next name to appear on the roll is that of
+Santos-Dumont, already famous for his remarkable
+achievements in building and navigating dirigible
+balloons, or airships. His first aeroplane flight was
+on August 22, 1906, and was but little more than
+rising clear of the ground.</p>
+
+<p>It was nearly seven months later when Delagrange
+added his name to the three then on the list of practical
+aviators. In about five months Bleriot joined
+them, and in a few more weeks Farman had placed
+his name on the roll. It is interesting to compare
+the insignificant figures of the first flights of these
+men with their successive feats as they gain in experience.</p>
+
+<p>Up to October 19, 1907, the flights recorded had
+been made with machines of the biplane type, but on
+that date, R. Esnault-Pelterie made a few short
+flights with a monoplane. A month later Santos-Dumont
+had gone over to the monoplane type, and
+the little group of seven had been divided into two
+classes&mdash;five biplanists and two monoplanists.</p>
+
+<p>On March 29, 1908, Delagrange started a new
+column in the record book by taking a passenger up
+with him, in this case, Farman. They flew only 453
+feet, but it was the beginning of passenger carrying.
+<span class="pagenum" id="Page_409">409</span></p>
+
+<p>During the first six months of 1908 only two more
+names were added to the roll&mdash;Baldwin and McCurdy&mdash;both
+on the biplane side. On July 4, 1908,
+Curtiss comes into the circle with his first recorded
+flight, in which he used a biplane of his own construction.
+The same day in France, Bleriot changed
+to the ranks of the monoplane men, with a flight
+measured in miles, instead of in feet. Two days
+later, Farman advanced his distance record from
+1.24 miles to 12.2 miles, and his speed record from
+about 21 miles an hour to nearly 39 miles an hour.
+In two days more, Delagrange had taken up the first
+woman passenger ever carried on an aeroplane; and
+a month later, Captain L. F. Ferber had made his
+first flights in public, and added his name to the
+growing legion of the biplanists.</p>
+
+<p>In the latter part of 1908, the Wrights seem to
+take possession of the record&mdash;Orville in America,
+and Wilbur in Europe&mdash;surpassing their own previous
+feats as well as those of others. Bleriot and Farman
+also steadily advance their performances to a
+more distinguished level.</p>
+
+<p>The record for 1909 starts off with three new
+names&mdash;Moore-Brabazon, and Legagneux in France,
+and Cody in England. Richardson, Count de Lambert,
+<span class="pagenum" id="Page_410">410</span>
+Calderara, Latham, Tissandier, Rougier, join
+the ranks of the aviators before the year is half gone,
+and a few days later Sommer and Paulhan add their
+names.</p>
+
+<p>Of these only Latham flies the monoplane type of
+machine, but at the Rheims tournament Delagrange
+appears as a monoplanist, increasing the little group
+to four; but, with Le Blon added later, they perform
+some of the most remarkable feats on record.</p>
+
+<p>The contest at Rheims in August is a succession of
+record-breaking and record-making achievements.
+But it is at Blackpool and Doncaster that the most
+distinct progress of the year is marked, by the daring
+flights of Le Blon and Latham in fierce gales.
+Spectators openly charged these men with foolhardiness,
+but it was of the first importance that it should
+be demonstrated that these delicately built machines
+can be handled safely in the most turbulent weather;
+and the fact that it has been done successfully will
+inspire every other aviator with a greater degree of
+confidence in his ability to control his machine in
+whatever untoward circumstances he may be placed.
+And such confidence is by far the largest element in
+safe and successful flying.
+<span class="pagenum" id="Page_411">411</span></p>
+
+<h3>NOTABLE AVIATION RECORDS TO CLOSE OF 1910</h3>
+
+<blockquote>
+
+<p><i>December 17, 1903</i>&mdash;Wilbur Wright with biplane,
+at Kitty Hawk, N. C., makes the first successful
+flight by man with power-propelled machine, a
+distance of 852 feet, in 59 seconds.</p>
+
+<p><i>November 9, 1904</i>&mdash;Wilbur Wright with biplane, at
+Dayton, O., flies 3 miles in 4 minutes and 30 seconds.
+(He and Orville made upward of 100 unrecorded
+flights in that year.)</p>
+
+<p><i>September 26, 1905</i>&mdash;Wilbur Wright with biplane
+“White Flier,” at Dayton, O., flies 11 miles in
+18 minutes and 9 seconds.</p>
+
+<p><i>September 29, 1905</i>&mdash;Orville Wright, with “White
+Flier,” at Dayton, O., flies 12 miles in 19 minutes
+and 55 seconds.</p>
+
+<p><i>October 3, 1905</i>&mdash;Wilbur Wright, with “White
+Flier” at Dayton, O., flies 15 miles in 25 minutes
+and 5 seconds.</p>
+
+<p><i>October 4, 1905</i>&mdash;Orville Wright with biplane
+“White Flier,” at Dayton, O., flies 21 miles in
+33 minutes and 17 seconds.</p>
+
+<p><i>October 5, 1905</i>&mdash;Wilbur Wright with “White
+<span class="pagenum" id="Page_412">412</span>
+Flier,” at Dayton, O., flies 24 miles in 38 minutes.
+(He made many unrecorded flights in that
+year.)</p>
+
+<p><i>August 22, 1906</i>&mdash;A. Santos-Dumont with biplane
+at Bagatelle, France, made his first public flight
+with an aeroplane, hardly more than rising clear
+of the ground.</p>
+
+<p><i>September 14, 1906</i>&mdash;Santos-Dumont with biplane,
+at Bagatelle, flies for 8 seconds.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_412.jpg" alt="" />
+<p class="caption">Santos-Dumont flying at Bagatelle in his cellular biplane.</p></div>
+
+<blockquote>
+
+<p><i>October 24, 1906</i>&mdash;Santos-Dumont with biplane, at
+Bagatelle, flies 160 feet in 4 seconds.</p>
+
+<p><i>November 13, 1906</i>&mdash;Santos-Dumont with biplane,
+at Bagatelle, flies 722 feet in 21 seconds. This
+feat is recorded as the first aeroplane flight made
+in Europe.</p>
+
+<p><i>March 16, 1907</i>&mdash;Leon Delagrange with first Voisin
+biplane, at Bagatelle, flies 30 feet.
+<span class="pagenum" id="Page_413">413</span></p>
+
+<p><i>August 6, 1907</i>&mdash;Louis Bleriot with a Langley machine,
+at Issy, France, flies 470 feet.</p>
+
+<p><i>October 15, 1907</i>&mdash;Henry Farman with biplane, at
+Issy, flies 937 feet in 21 seconds.</p>
+
+<p><i>October 19, 1907</i>&mdash;R. Esnault-Pelterie with monoplane,
+at Buc, France, makes short flights.</p>
+
+<p><i>October 26, 1907</i>&mdash;Farman with biplane, at Issy,
+flies 2,529 feet in a half circle, in 52 seconds.</p>
+
+<p><i>November 17, 1907</i>&mdash;Santos-Dumont with biplane,
+at Issy, makes several short flights, the longest
+being about 500 feet.</p>
+
+<p><i>November 21, 1907</i>&mdash;Santos-Dumont with monoplane
+at Bagatelle, makes several short flights,
+the longest being about 400 feet.</p>
+
+<p><i>January 13, 1908</i>&mdash;Farman with biplane, at Issy,
+makes the first flight in a circular course&mdash;3,279
+feet in 1 minute and 28 seconds.</p>
+
+<p><i>March 12, 1908</i>&mdash;F. W. Baldwin with biplane “Red
+Wing,” at Hammondsport, N. Y., flies 319 feet.</p>
+
+<p><i>March 21, 1908</i>&mdash;Farman with biplane, at Issy, flies
+1.24 miles in 3 minutes and 31 seconds.</p>
+
+<p><i>March 29, 1908</i>&mdash;Delagrange with biplane, at
+Ghent, Belgium, makes first recorded flight with
+one passenger (Farman), 453 feet.</p>
+
+<p><i>April 11, 1908</i>&mdash;Delagrange with biplane at Issy,
+<span class="pagenum" id="Page_414">414</span>
+flies 2.43 miles in 6 minutes and 30 seconds, winning
+the Archdeacon cup.</p>
+
+<p><i>May 18, 1908</i>&mdash;J. A. D. McCurdy with biplane
+“White Wing” at Hammondsport, flies 600
+feet.</p>
+
+<p><i>May 27, 1908</i>&mdash;Delagrange with biplane, at Rome,
+in the presence of the King of Italy, flies 7.9
+miles in 15 minutes and 25 seconds.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_414.jpg" alt="" />
+<p class="caption">The early Voisin biplane flown by Farman at Issy.</p></div>
+
+<blockquote>
+
+<p><i>May 30, 1908</i>&mdash;Farman with biplane, at Ghent,
+flies 0.77 miles with one passenger (Mr. Archdeacon).</p>
+
+<p><i>June 8, 1908</i>&mdash;Esnault-Pelterie with monoplane, at
+Buc, flies 0.75 miles, reaching an altitude of 100
+feet.</p>
+
+<p><i>June 22, 1908</i>&mdash;Delagrange with biplane, at Milan,
+<span class="pagenum" id="Page_415">415</span>
+Italy, flies 10.5 miles in 16 minutes and 30 seconds.</p>
+
+<p><i>July 4, 1908</i>&mdash;Glenn H. Curtiss with biplane, at
+Hammondsport, flies 5,090 feet, in 1 minute and
+42 seconds, winning <i>Scientific American</i> cup.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_415.jpg" alt="" />
+<p class="caption">The “June Bug” flown by Curtiss winning the <i>Scientific American</i> cup,
+July 4, 1908.</p></div>
+
+<blockquote>
+
+<p><i>July 4, 1908</i>&mdash;Bleriot with monoplane, at Issy, flies
+3.7 miles in 5 minutes and 47 seconds, making
+several circles.</p>
+
+<p><i>July 6, 1908</i>&mdash;Farman in biplane, at Ghent, flies
+<span class="pagenum" id="Page_416">416</span>
+12.2 miles in 19 minutes and 3 seconds, winning
+the Armengand prize.</p>
+
+<p><i>July 8, 1908</i>&mdash;Delagrange with biplane, at Turin,
+Italy, flies 500 feet with the first woman passenger
+ever carried on an aeroplane&mdash;Mrs. Peltier.</p>
+
+<p><i>August 9, 1908</i>&mdash;Wilbur Wright with biplane, at Le
+Mans, France, makes several short flights to
+prove the ease of control of his machine.</p>
+
+<p><i>August 8, 1908</i>&mdash;L. F. Ferber with biplane, at Issy,
+makes first trial flights.</p>
+
+<p><i>September 6, 1908</i>&mdash;Delagrange with biplane, at
+Issy, flies 15.2 miles in 29 minutes and 52 seconds,
+beating existing French records.</p>
+
+<p><i>September 8, 1908</i>&mdash;Orville Wright with biplane, at
+Fort Myer, Va., flies 40 miles in 1 hour and 2
+minutes, rising to 100 feet.</p>
+
+<p><i>September 9, 10, 11, 1908</i>&mdash;Orville Wright with biplane,
+at Fort Myer, makes several flights, increasing
+in duration from 57 minutes to 1 hour
+ten minutes and 24 seconds.</p>
+
+<p><i>September 12, 1908</i>&mdash;Orville Wright with biplane,
+at Fort Myer, flies 50 miles in 1 hour, 14
+minutes and 20 seconds, the longest flight on
+record.</p>
+
+<p><i>September 12, 1908</i>&mdash;Orville Wright with biplane,
+<span class="pagenum" id="Page_417">417</span>
+at Fort Myer, flies for 9 minutes and 6 seconds
+with one passenger (Major Squier), making a
+new record.</p>
+
+<p><i>September 17, 1908</i>&mdash;Orville Wright with biplane,
+at Fort Myer, flies 3 miles in 4 minutes, with
+Lieutenant Selfridge. The machine fell: Selfridge
+was killed and Wright severely injured.</p>
+
+<p><i>September 19, 1908</i>&mdash;L. F. Ferber with biplane, at
+Issy, flies 1,640 feet.</p>
+
+<p><i>September 21, 1908</i>&mdash;Wilbur Wright with biplane,
+at Auvours, flies 41 miles in 1 hour and 31 minutes.</p>
+
+<p><i>September 25, 1908</i>&mdash;Wilbur Wright with biplane,
+at Le Mans, France, flies 11 minutes and 35 seconds,
+with one passenger, making a new record.</p>
+
+<p><i>October 3, 1908</i>&mdash;Wilbur Wright with biplane, at
+Le Mans, France, flies 55 minutes and 37 seconds,
+with one passenger, making new record.</p>
+
+<p><i>October 6, 1908</i>&mdash;Wilbur Wright with biplane, at Le
+Mans, flies 1 hour 4 minutes and 26 seconds,
+with one passenger, breaking all records.</p>
+
+<p><i>October 10, 1908</i>&mdash;Wilbur Wright with biplane, at
+Auvours, flies 46 miles in 1 hour and 9 minutes,
+with one passenger (Mr. Painleve). Also carried
+35 others on different trips, one at a time.
+<span class="pagenum" id="Page_418">418</span></p>
+
+<p><i>October 21, 1908</i>&mdash;Bleriot with monoplane, at
+Toury, France, flies 4.25 miles in 6 minutes and
+40 seconds.</p>
+
+<p><i>October 30, 1908</i>&mdash;Farman with biplane at Chalons,
+France, makes a flight across country to Rheims&mdash;17
+miles in 20 minutes.</p>
+
+<p><i>October 31, 1908</i>&mdash;Farman with biplane, at Chalons,
+flies 23 minutes, reaching a height of 82
+feet.</p>
+
+<p><i>October 31, 1908</i>&mdash;Bleriot with monoplane, at
+Toury, flies 8.7 miles to Artenay, in 11 minutes,
+lands, and returns to Toury.</p>
+
+<p><i>December 18, 1908</i>&mdash;Wilbur Wright with biplane, at
+Auvours, flies 62 miles in 1 hour and 54 minutes,
+rising to 360 feet&mdash;making a world record.</p>
+
+<p><i>December 31, 1908</i>&mdash;Wilbur Wright with biplane,
+at Le Mans, flies 76.5 miles in 2 hours 18 minutes
+and 53 seconds, making a new world record,
+and winning the Michelin prize. The distance
+traversed (unofficial) is claimed to have been actually
+over 100 miles.</p>
+
+<p><i>January 28, 1909</i>&mdash;Moore-Brabazon with biplane,
+at Chalons, flies 3.1 miles, in practice with a
+Voison machine.</p>
+
+<p><i>February 14, 1909</i>&mdash;Legagneux with biplane, at
+<span class="pagenum" id="Page_419">419</span>
+Mourmelon, France, flies 1.2 miles, and in a second
+flight of 6.2 miles (10 kilometres), traces
+two circles.</p>
+
+<p><i>February 22, 1909</i>&mdash;S. F. Cody with biplane, at Aldershot,
+England, flies 1,200 feet in a 12-mile
+wind.</p>
+
+<p><i>February 23, 1909</i>&mdash;J. A. D. McCurdy, with the
+biplane “Silver Dart,” at Baddeck, Cape Breton,
+flies 2,640 feet.</p>
+
+<p><i>February 24, 1909</i>&mdash;McCurdy, with the biplane
+“Silver Dart,” at Baddeck, flies 4.5 miles.</p>
+
+<p><i>February 24, 1909</i>&mdash;Moore-Brabazon, with biplane,
+at Issy, flies 1.2 miles, tracing two circles.</p>
+
+<p><i>February 28, 1909</i>&mdash;Moore-Brabazon made several
+flights at Issy.</p>
+
+<p><i>March 8, 1909</i>&mdash;McCurdy, with biplane “Silver
+Dart,” at Baddeck, made five flights, the longest
+about 8 miles in 11 minutes and 15 seconds.</p>
+
+<p><i>March 10, 1909</i>&mdash;Santos-Dumont, with monoplane
+“Libellule,” at Bagatelle, flies 1,300 feet.</p>
+
+<p><i>March 11, 1909</i>&mdash;W. J. Richardson with a new
+form of aeroplane, at Dayton, O., flies for 38
+minutes, rising to a height of over 300 feet.</p>
+
+<p><i>March 11, 1909</i>&mdash;McCurdy with biplane “Silver
+Dart,” at Baddeck, flies 19 miles in 22 minutes.
+<span class="pagenum" id="Page_420">420</span></p>
+
+<p><i>March 17, 1909</i>&mdash;Count de Lambert (pupil of Wilbur
+Wright) made his first flight alone in biplane,
+at Pau, France. He remained in the air
+3 minutes.</p>
+
+<p><i>March 18, 1909</i>&mdash;McCurdy, with biplane “Silver
+Dart,” at Baddeck, flies 16 miles, completing a
+record of an even 1,000 miles in the air within
+a period of 10 months.</p>
+
+<p><i>March 18, 1909</i>&mdash;F. W. Baldwin with biplane “Silver
+Dart,” at Baddeck, made a short flight.</p>
+
+<p><i>March 20, 1909</i>&mdash;Wilbur Wright, with biplane, at
+Pau, succeeds in rising from the ground without
+the starting device previously used. He makes
+several flights.</p>
+
+<p><i>March 24, 1909</i>&mdash;Count de Lambert with biplane,
+at Pau, flies 15.6 miles in 27 minutes and 11
+seconds.</p>
+
+<p><i>April 10, 1909</i>&mdash;Santos-Dumont with monoplane
+“Demoiselle,” at St. Cyr, France, flies 1.2 miles.</p>
+
+<p><i>April 13, 1909</i>&mdash;Count de Lambert with biplane, at
+Pau, flies for 1 minute and 30 seconds, with one
+passenger (Leon Delagrange).</p>
+
+<p><i>April 16, 1909</i>&mdash;Wilbur Wright with biplane, at
+Rome, Italy, made many flights, taking up many
+passengers, one at a time.
+<span class="pagenum" id="Page_421">421</span></p>
+
+<p><i>April 27, 1909</i>&mdash;Legagneux with Voisin biplane, at
+Vienna, flies 2.5 miles in 3 minutes and 26 seconds.</p>
+
+<p><i>April 28, 1909</i>&mdash;Lieutenant Mario Calderara (pupil
+of Wilbur Wright) with biplane, at Rome, made
+his first public flight, remaining in the air 10
+minutes.</p>
+
+<p><i>April 30, 1909</i>&mdash;Moore-Brabazon with biplane, in
+England, flies 4.5 miles.</p>
+
+<p><i>May 14, 1909</i>&mdash;S. F. Cody, with the army biplane,
+at Aldershot, flies 1 mile.</p>
+
+<p><i>May 19, 1909</i>&mdash;Hubert Latham, with Antoinette
+monoplane, at Chalons, flies 1,640 feet.</p>
+
+<p><i>May 20, 1909</i>&mdash;Paul Tissandier (pupil of Wilbur
+Wright) with biplane at Pau, flies 35.7 miles.</p>
+
+<p><i>May 23, 1909</i>&mdash;Delagrange, with biplane, at Juvissy,
+flies 3.6 miles in 10 minutes and 18 seconds,
+winning the Lagatineri prize.</p>
+
+<p><i>May 23, 1909</i>&mdash;Henri Rougier, with biplane, at Juvissy,
+flies 18.6 miles (30 kilometres).</p>
+
+<p><i>May 30, 1909</i>&mdash;Bleriot, with monoplane at Issy,
+flies 8.7 miles.</p>
+
+<p><i>June 5, 1909</i>&mdash;Latham, with monoplane, at Chalons,
+flies for 1 hour 7 minutes and 37 seconds in wind
+and rain.
+<span class="pagenum" id="Page_422">422</span></p>
+
+<p><i>June 6, 1909</i>&mdash;Latham, with monoplane, at Juvissy,
+flies 10 miles across country.</p>
+
+<p><i>June 12, 1909</i>&mdash;Latham, with monoplane, at Juvissy,
+flies 30 miles in 39 minutes, winning the
+Goupy prize.</p>
+
+<p><i>June 12, 1909</i>&mdash;Delagrange, with biplane, at Juvissy,
+makes cross country flight of 3.7 miles.</p>
+
+<p><i>June 12, 1909</i>&mdash;Bleriot, with monoplane, at Juvissy,
+flies 984 feet, with two passengers&mdash;Santos-Dumont
+and Fournier.</p>
+
+<p><i>June 13 1909</i>&mdash;Ferber, with Voisin biplane, at Juvissy,
+flies 3.1 miles in 5 minutes and 30 seconds.</p>
+
+<p><i>June 19, 1909</i>&mdash;Santos-Dumont, with monoplane, at
+Issy, makes several flights.</p>
+
+<p><i>July 4, 1909</i>&mdash;Roger Sommer with biplane, at Chalons,
+flies 3.75 miles on Farman machine.</p>
+
+<p><i>July 10, 1909</i>&mdash;Louis Paulhan, with biplane, at
+Douai, France, makes his first flight&mdash;1.25 miles.</p>
+
+<p><i>July 13, 1909</i>&mdash;Curtiss, with biplane, at Mineola,
+L. I., flies 1.5 miles in 3 minutes.</p>
+
+<p><i>July 13, 1909</i>&mdash;Bleriot, with monoplane, at Mondesir,
+makes a flight of 26 miles across country in
+44 minutes and 30 seconds.</p>
+
+<p><i>July 15, 1909</i>&mdash;Paulhan with biplane, at Douai,
+<span class="pagenum" id="Page_423">423</span>
+flies for 1 minute and 17 seconds, soaring to an
+altitude of 357 feet.</p>
+
+<p><i>July 17, 1909</i>&mdash;Orville Wright, with biplane, at
+Fort Myer, flies 16 minutes and 40 seconds, at a
+speed of 40 miles an hour.</p>
+
+<p><i>July 17, 1909</i>&mdash;Curtiss, with biplane, at Mineola,
+makes 15 miles in 21 minutes, describing circles
+in both directions, as in the figure 8.</p>
+
+<p><i>July 18, 1909</i>&mdash;Curtiss, with biplane, at Hempstead
+Plains, L. I., flies 29½ miles in 52 minutes and
+30 seconds, a flight exceeded only by the Wrights,
+in America, and Bleriot, Latham, and Paulhan,
+in Europe.</p>
+
+<p><i>July 18, 1909</i>&mdash;Farman, with biplane, at Chalons,
+flies for 1 hour and 23 minutes, making his first
+long flight.</p>
+
+<p><i>July 18, 1909</i>&mdash;Sommer, with biplane, at Chalons,
+makes his longest flight&mdash;1 hour and 40 minutes.</p>
+
+<p><i>July 19, 1909</i>&mdash;Latham, with monoplane, at Calais,
+France, makes his first attempt to cross the Channel
+to Dover. He flies 11 miles, and then his
+machine falls into the sea.</p>
+
+<p><i>July 19, 1909</i>&mdash;Paulhan, with biplane, at Douai,
+makes a cross-country flight of 12.1 miles in 22
+minutes and 53 seconds.
+<span class="pagenum" id="Page_424">424</span></p>
+
+<p><i>July 20, 1909</i>&mdash;Orville Wright, with biplane, at
+Fort Myer, flies 1 hour and 20 minutes.</p>
+
+<p><i>July 21, 1909</i>&mdash;Orville Wright, with biplane, at
+Fort Myer, flies 1 hour and 29 minutes.</p>
+
+<p><i>July 21, 1909</i>&mdash;E. Lefebvre, with biplane, at La
+Haye, France, flies 2 miles.</p>
+
+<p><i>July 21, 1909</i>&mdash;S. F. Cody, with biplane, at Aldershot,
+flies 4 miles.</p>
+
+<p><i>July 23, 1909</i>&mdash;Farman, with biplane, at Chalons,
+makes a cross-country flight to Suippes&mdash;40
+miles in 1 hour and five minutes.</p>
+
+<p><i>July 23, 1909</i>&mdash;Paulhan, with biplane, at Douai,
+flies 43.5 miles in 1 hour 17 minutes and 19
+seconds.</p>
+
+<p><i>July 24, 1909</i>&mdash;Curtiss in biplane, at Hempstead
+Plains, flies 25 miles in 52 minutes and 30 seconds,
+winning the <i>Scientific American</i> cup the
+second time.</p>
+
+<p><i>July 25, 1909</i>&mdash;Bleriot, with monoplane, at Calais,
+flies to Dover, England, across the English Channel&mdash;32
+miles in 37 minutes.</p>
+
+<p><i>July 27, 1909</i>&mdash;Orville Wright, with biplane, at
+Fort Myer, flies 1 hour and 13 minutes, with one
+passenger, securing acceptance of Wright machine
+<span class="pagenum" id="Page_425">425</span>
+by U. S. Government on the duration specifications.</p>
+
+<p><i>July 27, 1909</i>&mdash;Latham, with monoplane, at Calais,
+flies 20 miles in a second attempt to cross the
+English Channel. When near Dover the machine
+fell.</p>
+
+<p><i>July 27, 1909</i>&mdash;Sommer, with biplane, at Chalons,
+flies to Vadenay and back&mdash;25 miles in 1 hour
+23 minutes and 30 seconds.</p>
+
+<p><i>July 30, 1909</i>&mdash;Orville Wright, with biplane, at
+Fort Myer, established a world record with one
+passenger in a cross-country flight to Shuter’s
+Hill and back&mdash;about 10 miles in 14 minutes and
+40 seconds, a speed of about 42 miles an hour&mdash;winning
+a bonus of $25,000 from the U. S. Government.</p>
+
+<p><i>August 1, 1909</i>&mdash;Sommer, with biplane, at Chalons,
+flies 1 hour 50 minutes and 30 seconds, at an
+average height of 80 feet, over a distance estimated
+at 70 miles, surpassing all French records.</p>
+
+<p><i>August 2, 1909</i>&mdash;McCurdy, with a new type of machine,
+at Petawawa, makes several flights.</p>
+
+<p><i>August 2, 1909</i>&mdash;F. W. Baldwin, with biplane, at
+Petawawa, makes several short flights.</p>
+
+<p><i>August 2, 1909</i>&mdash;Sommer, with biplane, at Chalons,
+<span class="pagenum" id="Page_426">426</span>
+flies to Suippes&mdash;9 miles, at the rate of 45 miles
+an hour.</p>
+
+<p><i>August 4, 1909</i>&mdash;Sommer, with biplane, at Chalons,
+in the effort to beat Wilbur Wright’s record,
+flies for 2 hours 0 minutes and 10 seconds
+(Wright’s record flight was 2 hours 20 minutes
+and 23 seconds, made on December 31, 1908).</p>
+
+<p><i>August 5, 1909</i>&mdash;E. Bunau-Varilla, with Voisin biplane,
+at Chalons, flies for 15 minutes.</p>
+
+<p><i>August 6, 1909</i>&mdash;Legagneux, with biplane, at Stockholm,
+flies with one passenger, 3,280 feet.</p>
+
+<p><i>August 6, 1909</i>&mdash;Paulhan, with biplane, at Dunkerque,
+France, flies for 18 minutes and 20 seconds,
+reaching an altitude of 200 feet.</p>
+
+<p><i>August 7, 1909</i>&mdash;Paulhan, with Voisin biplane, at
+Dunkerque, flies 23 miles in 33 minutes.</p>
+
+<p><i>August 7, 1909</i>&mdash;Sommer, with Voisin biplane, at
+Chalons, flies for 2 hours 27 minutes and 15
+seconds, making new world record for duration.</p>
+
+<p><i>August 13, 1909</i>&mdash;Charles F. Willard, with biplane,
+at Hempstead Plains, made the longest cross-country
+flight on record for America&mdash;about 12
+miles in 19 minutes and 30 seconds. The breaking
+of his engine caused him to come down. He
+landed without mishap.
+<span class="pagenum" id="Page_427">427</span></p>
+
+<p><i>August 22, 1909</i>&mdash;Sommer, with biplane, at Rheims,
+France, flies 1 hour 19 minutes and 30 seconds.</p>
+
+<p><i>August 22, 1909</i>&mdash;Legagneux, with biplane, at
+Rheims, flies 6.2 miles in 9 minutes and 56 seconds,
+winning third prize for speed over course
+of 10 kilometres.</p>
+
+<p><i>August 22, 1909</i>&mdash;Tissandier, with biplane, at
+Rheims, flies 18.6 miles in 29 minutes. (He
+won with this record the third prize for speed
+over 30 kilometres.)</p>
+
+<p><i>August 22, 1909</i>&mdash;E. Bunau-Varilla, with biplane,
+at Rheims, flies 6.2 miles in 13 minutes and 30
+seconds. (With this record he won the thirteenth
+prize for speed over course of 10 kilometres.)</p>
+
+<p><i>August 23, 1909</i>&mdash;Delagrange, with monoplane, at
+Rheims, flies 6.2 miles in 11 minutes and 4 seconds.
+(He won the tenth prize for speed over
+10 kilometres.)</p>
+
+<p><i>August 23, 1909</i>&mdash;Curtiss, with biplane, at Rheims,
+flies 6.2 miles in 8 minutes and 35 seconds&mdash;a
+speed of 42.3 miles an hour&mdash;beating the record
+for speed over course of 10 kilometres.</p>
+
+<p><i>August 23, 1909</i>&mdash;Paulhan, with biplane, at Rheims,
+flies 18.6 miles in 38 minutes and 12 seconds,
+reaching an altitude of 295 feet.
+<span class="pagenum" id="Page_428">428</span></p>
+
+<p><i>August 23, 1909</i>&mdash;Paulhan, with biplane, at
+Rheims, flies 34.8 miles in an endurance test.</p>
+
+<p><i>August 25, 1909</i>&mdash;Paulhan, with biplane, at Rheims,
+flies 82 miles in 2 hours 43 minutes and 25
+seconds. (With this record he won the third
+prize for duration of flight.)</p>
+
+<p><i>August 25, 1909</i>&mdash;Curtiss, with biplane, at Rheims,
+flies 6.2 miles in 8 minutes and 44 seconds, again
+reducing the time for 10 kilometres.</p>
+
+<p><i>August 25, 1909</i>&mdash;Bleriot, with monoplane, at
+Rheims, flies 6.2 miles in 8 minutes and 4 seconds,
+making a new record for speed over the
+course of 10 kilometres.</p>
+
+<p><i>August 26, 1909</i>&mdash;Curtiss, in biplane, at Rheims,
+flies 19 miles in 29 minutes. (With this record
+he won the tenth prize for duration of flight.)</p>
+
+<p><i>August 26, 1909</i>&mdash;Count de Lambert, with biplane,
+at Rheims, flies 72 miles in 1 hour and 52 minutes.
+(With this record he won the fourth prize
+for duration of flight.)</p>
+
+<p><i>August 26, 1909</i>&mdash;Latham, with monoplane, at
+Rheims, flies 96.5 miles in 2 hours 17 minutes
+and 21 seconds. (With this record he won the
+second prize for duration of flight.)</p>
+
+<p><i>August 27, 1909</i>&mdash;Farman, with biplane, at Rheims,
+<span class="pagenum" id="Page_429">429</span>
+flies 112 miles in 3 hours 4 minutes and 57 seconds.
+(This record won for him the first prize
+for duration of flight.)</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_429.jpg" alt="" />
+<p class="caption">Latham flying in his Antoinette at Rheims. To view this properly the picture
+should be held overhead.</p></div>
+
+<blockquote>
+
+<p><i>August 27, 1909</i>&mdash;Latham, with monoplane, at
+Rheims, flies to an altitude of 508 feet. (With
+this record he won first prize for altitude.)</p>
+
+<p><i>August 27, 1909</i>&mdash;Delagrange, with monoplane, at
+Rheims, flies 31 miles. (With this record he won
+the eighth prize for duration of flight.)
+<span class="pagenum" id="Page_430">430</span></p>
+
+<p><i>August 27, 1909</i>&mdash;Sommer, with biplane, at Rheims,
+flies 37 miles. He won the seventh prize for distance.</p>
+
+<p><i>August 27, 1909</i>&mdash;Tissandier, with biplane, at
+Rheims, flies 69 miles. (This record won for him
+the sixth prize for distance.)</p>
+
+<p><i>August 27, 1909</i>&mdash;Lefebvre, with biplane, at
+Rheims, flies 12.4 miles in 20 minutes and 47
+seconds, exhibiting great daring and skill. (He
+was fined for “recklessness.”)</p>
+
+<p><i>August 27, 1909</i>&mdash;Bleriot, with monoplane, at
+Rheims, flies 25 miles in 41 minutes. (This record
+won for him the ninth prize for distance
+flown.)</p>
+
+<p><i>August 28, 1909</i>&mdash;Lefebvre, with biplane, at Rheims,
+makes a spectacular flight for 11 minutes with
+one passenger.</p>
+
+<p><i>August 28, 1909</i>&mdash;Curtiss, with biplane, at Rheims,
+flies 12.4 miles in 15 minutes and 56 seconds,
+winning the Gordon Bennett cup.</p>
+
+<p><i>August 28, 1909</i>&mdash;Bleriot, with monoplane, at
+Rheims, flies 6.2 miles in 7 minutes and 48 seconds.
+(With this record he won the first prize
+for speed over course of 10 kilometres.)</p>
+
+<p><i>August 29, 1909</i>&mdash;Farman, with biplane, at Rheims,
+<span class="pagenum" id="Page_431">431</span>
+flies 6.2 miles with two passengers, in 10 minutes
+and 30 seconds, winning a prize.</p>
+
+<p><i>August 29. 1909</i>&mdash;Curtiss, with biplane, at Rheims,
+flies 18.6 miles in 23 minutes and 30 seconds.
+(With this record he won the first prize for
+speed over course of 30 kilometres.)</p>
+
+<p><i>August 29, 1909</i>&mdash;Curtiss, with biplane, at Rheims,
+flies 6.2 miles in 7 minutes and 51 seconds, winning
+the second prize for speed over course of 10
+kilometres.</p>
+
+<p><i>August 29, 1909</i>&mdash;Rougier, with biplane, at Rheims,
+rises to a height of 180 feet, winning the fourth
+prize for altitude.</p>
+
+<p><i>August 29, 1909</i>&mdash;E. Bunau-Varilla, with biplane,
+at Rheims, flies 18.6 miles in 38 minutes and
+31 seconds. (With this record he won the
+eighth prize for speed over course of 30 kilometres.)</p>
+
+<p><i>August 29, 1909</i>&mdash;Orville Wright, with biplane, at
+Berlin, makes several short flights.</p>
+
+<p><i>August 29, 1909</i>&mdash;S. F. Cody, with biplane, at Aldershot,
+flies 10 miles with one passenger.</p>
+
+<p><i>September 4, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, flies for 55 minutes.</p>
+
+<p><i>September 6, 1909</i>&mdash;Sommer, with biplane, at Nancy,
+<span class="pagenum" id="Page_432">432</span>
+France, flies 25 miles in 35 minutes. He
+takes up a number of passengers; one at a time.</p>
+
+<p><i>September 7, 1909</i>&mdash;Lefebvre, with biplane, at Juvissy,
+is killed by the breaking of his machine
+in the air after he had flown 1,800 feet.</p>
+
+<p><i>September 8, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, flies 17 minutes with one passenger&mdash;Captain
+Hildebrandt.</p>
+
+<p><i>September 8, 1909</i>&mdash;S. F. Cody, with biplane, at Aldershot,
+flies to Farnborough and back&mdash;46 miles
+in 1 hour and 3 minutes. This is the first recorded
+cross-country flight in England.</p>
+
+<p><i>September 9, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, flies for 15 minutes with one passenger&mdash;Captain
+Englehardt.</p>
+
+<p><i>September 9, 1909</i>&mdash;Paulhan, with biplane, at Tournai,
+Belgium, flies 12.4 miles in 17 minutes.</p>
+
+<p><i>September 9, 1909</i>&mdash;Rougier, with biplane, at Brescia,
+flies 12 minutes and 10 seconds, soaring to
+a height of 328 feet.</p>
+
+<p><i>September 10, 1909</i>&mdash;Sommer, with biplane, at
+Nancy, flies 18 miles, accompanying troops on
+review.</p>
+
+<p><i>September 11, 1909</i>&mdash;Sommer, with biplane, at
+Nancy, flies to Lenoncourt&mdash;24 miles.
+<span class="pagenum" id="Page_433">433</span></p>
+
+<p><i>September 11, 1909</i>&mdash;Curtiss, with biplane, at Brescia,
+flies 31 miles in 49 minutes and 24 seconds,
+winning the first prize for speed.</p>
+
+<p><i>September 12, 1909</i>&mdash;Rougier, with biplane, at
+Brescia, flies 31 miles in 1 hour 10 minutes
+and 18 seconds, soaring to a height of 380 feet.</p>
+
+<p><i>September 12, 1909</i>&mdash;Calderara, with biplane, at
+Brescia, flies 6.3 miles with one passenger, winning
+a prize.</p>
+
+<p><i>September 13, 1909</i>&mdash;Paulhan, with biplane, at
+Tournai, flies to Taintiguies and back in 1 hour
+and 35 minutes.</p>
+
+<p><i>September 13, 1909</i>&mdash;Santos-Dumont, with monoplane,
+at St. Cyr, France, flies 5 miles in 12
+minutes, to Buc, to visit Maurice Guffroy, on a
+bet of $200 that each would be the first to visit
+the other.</p>
+
+<p><i>September 15, 1909</i>&mdash;Ferber, with biplane, at Boulogne,
+France, flies to Wimeroux&mdash;6 miles in 9
+minutes.</p>
+
+<p><i>September 15, 1909</i>&mdash;Calderara, with biplane, at
+Brescia, flies 5.6 miles with one passenger, winning
+the Oldofredi prize.</p>
+
+<p><i>September 17, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, flies for 54 minutes and 26 seconds,
+<span class="pagenum" id="Page_434">434</span>
+rising to an altitude of 765 feet (estimated). He
+afterward flew for 47 minutes and 5 seconds with
+Captain Englehardt.</p>
+
+<p><i>September 17, 1909</i>&mdash;Santos-Dumont, with monoplane,
+at St. Cyr, flies 10 miles in 16 minutes
+across country.</p>
+
+<p><i>September 17, 1909</i>&mdash;Paulhan, with biplane, at Ostend,
+Belgium, flies 1.24 miles in 3 minutes and
+16 seconds, along the water front and out over
+the sea.</p>
+
+<p><i>September 18, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, establishes a world record by flying for
+1 hour 35 minutes and 47 seconds, with one
+passenger&mdash;Captain Englehardt.</p>
+
+<p><i>September 18, 1909</i>&mdash;Paulhan, with biplane, at Ostend,
+flies for 1 hour over sea front, circling over
+the water; winning a prize of $5,000.</p>
+
+<p><i>September 20, 1909</i>&mdash;Rougier, with biplane, at
+Brescia, broke the record for high flying by
+reaching an altitude of 645 feet (official measurement).</p>
+
+<p><i>September 20, 1909</i>&mdash;Calderara, with biplane, at
+Brescia, flies 31 miles in 50 minutes and 51 seconds,
+winning the second prize for speed.</p>
+
+<p><i>September 22, 1909</i>&mdash;Captain Ferber, with a biplane,
+<span class="pagenum" id="Page_435">435</span>
+at Boulogne, flies 1 mile, when, his engine
+breaking in the air, his machine falls and
+he is killed.</p>
+
+<p><i>September 25, 1909</i>&mdash;Wilbur Wright, with biplane,
+at New York, flies from Governor’s Island around
+the Statue of Liberty.</p>
+
+<p><i>September 27, 1909</i>&mdash;Latham, in monoplane, at
+Berlin, flies 6.5 miles across country in 13 minutes.</p>
+
+<p><i>September 28, 1909</i>&mdash;Rougier, with biplane, at Berlin,
+flies 31 miles in 54 minutes, soaring to an altitude
+of 518 feet.</p>
+
+<p><i>September 29, 1909</i>&mdash;Latham in monoplane, at Berlin,
+flies 42 miles in 1 hour and 10 minutes,
+winning the second prize for distance.</p>
+
+<p><i>September 29, 1909</i>&mdash;Rougier, with biplane, at Berlin,
+flies 48 miles in 1 hour and 35 minutes.</p>
+
+<p><i>September 29, 1909</i>&mdash;Curtiss, with biplane, at New
+York, makes flights about the harbor from Governor’s
+Island.</p>
+
+<p><i>September 30, 1909</i>&mdash;Orville Wright, with biplane,
+at Berlin, soars to a height of 902 feet, making
+a world record for altitude.</p>
+
+<p><i>September 30, 1909</i>&mdash;Latham, with monoplane, at
+Berlin, flies 51 miles in 1 hour and 23 minutes.
+<span class="pagenum" id="Page_436">436</span></p>
+
+<p><i>October 1, 1909</i>&mdash;Rougier, with biplane, at Berlin,
+flies 80 miles in 2 hours and 38 minutes, winning
+the first prize for distance and speed.</p>
+
+<p><i>October 2, 1909</i>&mdash;Orville Wright, with biplane, at
+Berlin, makes a flight of 10 minutes’ duration
+with the Crown Prince of Germany.</p>
+
+<p><i>October 3, 1909</i>&mdash;Farman, with biplane, at Berlin,
+flies 62 miles in 1 hour and 40 minutes, winning
+the third prize for distance and speed.</p>
+
+<p><i>October 4, 1909</i>&mdash;Orville Wright, with biplane, at
+Berlin, soared to an altitude of 1,600 feet, making
+a world record.</p>
+
+<p><i>October 4, 1909</i>&mdash;Wilbur Wright, with biplane, at
+New York, flies from Governor’s Island to
+Grant’s Tomb and back&mdash;21 miles in 33 minutes
+and 33 seconds.</p>
+
+<p><i>October 10, 1909</i>&mdash;Curtiss, with biplane, at St.
+Louis, Mo., makes several flights at the Centennial
+celebration.</p>
+
+<p><i>October 10, 1909</i>&mdash;Paulhan, with biplane, at Pt.
+Aviation, flies 21.5 miles in 21 minutes and 48
+seconds.</p>
+
+<p><i>October 12, 1909</i>&mdash;Paulhan, with biplane, at Pt.
+Aviation, flies 3.6 miles in 6 minutes and 11 seconds,
+winning the prize for slowest flight.
+<span class="pagenum" id="Page_437">437</span></p>
+
+<p><i>October 16, 1909</i>&mdash;Curtiss, with biplane, at Chicago,
+makes exhibition flights at 45 miles per hour.</p>
+
+<p><i>October 16, 1909</i>&mdash;Sommer, with biplane, at Doncaster,
+England, flies 9.7 miles in 21 minutes and
+45 seconds, making the record for Great Britain.</p>
+
+<p><i>October 16, 1909</i>&mdash;Delagrange, with monoplane, at
+Doncaster, flies 5.75 miles in 11 minutes and 25
+seconds.</p>
+
+<p><i>October 16, 1909</i>&mdash;Cody, with biplane, at Doncaster,
+flies 3,000 feet, when his machine is wrecked,
+and he is injured.</p>
+
+<p><i>October 18, 1909</i>&mdash;Paulhan, with biplane, at Blackpool,
+England, flies 14 miles in 25 minutes and
+53 seconds.</p>
+
+<p><i>October 18, 1909</i>&mdash;Rougier, with biplane, at Blackpool,
+flies 17.7 miles in 24 minutes and 43 seconds,
+winning the second prize.</p>
+
+<p><i>October 18, 1909</i>&mdash;Farman, with biplane, at Blackpool,
+flies 14 miles in 23 minutes.</p>
+
+<p><i>October 18, 1909</i>&mdash;Le Blon, with monoplane, at
+Doncaster, flies 22 miles in 30 minutes, in a rainstorm,
+winning the Bradford cup.</p>
+
+<p><i>October 18, 1909</i>&mdash;Count de Lambert, with biplane,
+at Juvissy, flies 31 miles to the Eiffel Tower in
+Paris, and back, in 49 minutes and 39 seconds.
+<span class="pagenum" id="Page_438">438</span></p>
+
+<p><i>October 19, 1909</i>&mdash;Le Blon, with monoplane, at
+Doncaster, flies 15 miles in a gale.</p>
+
+<p><i>October 19, 1909</i>&mdash;Paulhan, with biplane, at Blackpool,
+flies 15.7 miles in 32 minutes and 18 seconds,
+winning the third prize.</p>
+
+<p><i>October 20, 1909</i>&mdash;Farman, with biplane, at Blackpool,
+flies 47 miles in 1 hour, 32 minutes, and
+16 seconds, winning the first prize&mdash;$10,000.</p>
+
+<p><i>October 20, 1909</i>&mdash;Le Blon, with monoplane, at
+Doncaster, makes a spectacular flight in a fierce
+gale.</p>
+
+<p><i>October 21, 1909</i>&mdash;Count de Lambert, with biplane,
+at Pt. Aviation, flies 1.25 miles in 1 minute
+and 57 seconds, winning prize of $3,000 for
+speed.</p>
+
+<p><i>October 22, 1909</i>&mdash;Latham, with monoplane, at
+Blackpool, flies in a squally gale blowing from
+30 to 50 miles an hour. When headed into the
+wind the machine moved backward in relation
+to points on the ground. Going before the wind,
+it passed points on the ground at a speed of nearly
+100 miles an hour. This flight, twice around
+the course, is the most difficult feat accomplished
+by any aviator up to this date.</p>
+
+<p><i>October 26, 1909</i>&mdash;Sommer, with biplane, at Doncaster,
+<span class="pagenum" id="Page_439">439</span>
+flies 29.7 miles in 44 minutes and 53 seconds,
+winning the Whitworth cup.</p>
+
+<p><i>October 26, 1909</i>&mdash;Delagrange, with monoplane, at
+Doncaster, flies 6 miles in 7 minutes and 36 seconds&mdash;a
+speed of over 50 miles an hour.</p>
+
+<p><i>October 30, 1909</i>&mdash;Moore-Brabazon, with biplane, at
+Shell Beach, England, wins a prize of $5,000 for
+flight with a British machine.</p>
+
+<p><i>November 3, 1909</i>&mdash;Farman, with biplane, at Mourmelon,
+France, flies 144 miles in 4 hours 6 minutes
+and 25 seconds, far surpassing his previous
+best record of 112 miles in 3 hours 4 minutes
+and 57 seconds, made at Rheims, and winning
+the Michelin cup for duration and distance.</p>
+
+<p><i>November 19, 1909</i>&mdash;Paulhan, with biplane, at
+Mourmelon, broke the record for height by ascending
+to 1,170 feet, in a wind blowing from 20
+to 25 miles an hour.</p>
+
+<p><i>November 19, 1909</i>&mdash;Latham, with Antoinette monoplane,
+surpassed Paulhan’s record by rising to
+an altitude of 1,333 feet.</p>
+
+<p><i>November 20, 1909</i>&mdash;Paulhan, with biplane, at
+Mourmelon, flies to Chalons and back&mdash;37 miles
+in 55 minutes.</p>
+
+<p><i>December 1, 1909</i>&mdash;Latham, with monoplane, at
+<span class="pagenum" id="Page_440">440</span>
+Mourmelon, soars to 1,500 feet in a 40-mile
+gale.</p>
+
+<p><i>December 30, 1909</i>&mdash;Delagrange, with monoplane,
+at Juvissy, flies 124 miles in 2 hours and 32 minutes&mdash;an
+average speed of 48.9 miles per hour,
+surpassing all previous records.</p>
+
+<p><i>December 31, 1909</i>&mdash;Farman at Chartres, France,
+flies to Orleans&mdash;42 miles in 50 minutes.</p>
+
+<p><i>December 31, 1909</i>&mdash;Maurice Farman, at Mourmelon,
+defending his brother Henry’s record
+against competing aviators, flies 100 miles in 2
+hours and 45 minutes, without a fault. The
+Michelin cup remains in his brother’s possession.</p>
+
+<p><i>January 7, 1910</i>&mdash;Latham, with Antoinette monoplane,
+at Chalons, rises to height of 3,281 feet
+(world’s record).</p>
+
+<p><i>January 10, 1910</i>&mdash;Opening of aviation meet at Los
+Angeles, Cal.</p>
+
+<p><i>January 12, 1910</i>&mdash;Paulhan, Farman biplane, at
+Los Angeles, rises to height of 4,146 feet.
+(World’s record.)</p>
+
+<p><i>January 17, 1910</i>&mdash;Paulhan, Farman biplane, at
+Los Angeles, flies 75 miles in 1 hour 58 minutes
+and 27⅖ seconds.</p>
+
+<p><i>February 7, 1910</i>&mdash;First flight in South America.
+<span class="pagenum" id="Page_441">441</span>
+Bregi, Voisin biplane, makes two flights near
+Buenos Aires.</p>
+
+<p><i>February 7, 1910</i>&mdash;Duray, with Farman biplane, at
+Heliopolis, Egypt, flies 5 kilometres in 4 minutes
+and 12⅘ seconds. (World’s record.)</p>
+
+<p><i>April 8, 1910</i>&mdash;D. Kinet, with Farman biplane, at
+Mourmelon, flies for 2 hours 19 minutes and 4⅖
+seconds with passenger, covering 102 miles.
+(World’s record for passenger flight.)</p>
+
+<p><i>April 11, 1910</i>&mdash;E. Jeannin, with Farman biplane,
+flies 2 hours 1 minute and 55 seconds, at Johannisthal.
+(German record.)</p>
+
+<p><i>April 15, 1910</i>&mdash;Opening of Nice meeting.</p>
+
+<p><i>April 17, 1910</i>&mdash;Paulhan, with Farman biplane,
+flies from Chevilly to Arcis-sur-Aube, 118 miles.
+(Record cross-country flight.)</p>
+
+<p><i>April 23, 1910</i>&mdash;Grahame-White, with Farman biplane,
+flies from Park Royal, London, to Rugby
+(83 miles) in 2 hours and 1 minute. Starting
+again in 55 minutes, flies to Whittington in 1
+hour and 5 minutes.</p>
+
+<p><i>April 27, 1910</i>&mdash;Paulhan, with Farman biplane,
+starts from Hendon, London, at 5.31 <small>P. M.</small>, flies
+within 5 mile circle and continues to Lichfield,
+arriving 8.10 <small>P. M.</small> (117 miles). Grahame-White
+<span class="pagenum" id="Page_442">442</span>
+starts from Wormwood Scrubs, London, at
+6.29 <small>P. M.</small>, flies to Roade, arriving 7.55 <small>P. M.</small>
+(60 miles).</p>
+
+<p><i>April 28, 1910</i>&mdash;Paulhan flies from Lichfield to
+within 5 miles of Manchester, winning the £10,000
+<i>Daily Mail</i> prize.</p>
+
+<p><i>April 30, 1910</i>&mdash;Opening of meeting at Tours,
+France.</p>
+
+<p><i>May 1, 1910</i>&mdash;Opening of flying-week at Barcelona.</p>
+
+<p><i>May 3, 1910</i>&mdash;Wiencziers, with Antoinette monoplane,
+twice circles the Strassburg cathedral.</p>
+
+<p><i>May 6, 1910</i>&mdash;Olieslagers, with Bleriot monoplane,
+makes flight of 18 minutes and 20 seconds above
+the sea at Barcelona, and over the fortress of
+Monjuich.</p>
+
+<p><i>May 13, 1910</i>&mdash;Engelhardt, with Wright biplane, at
+Berlin, flies 2 hours 21 minutes and 45 seconds.
+(German record.)</p>
+
+<p><i>May 15, 1910</i>&mdash;Kinet, with Farman biplane, flies
+2 hours and 51 minutes with a passenger at
+Mourmelon, making the world’s record for passenger
+flight.</p>
+
+<p><i>May 15, 1910</i>&mdash;Olieslagers, with Bleriot monoplane,
+flies 15 miles over the sea at Genoa.</p>
+
+<p><i>May 21, 1910</i>&mdash;M. de Lesseps, with Bleriot monoplane,
+<span class="pagenum" id="Page_443">443</span>
+flies from Calais to Dover in 37 minutes,
+winning £500 prize offered by M. M. Ruinart.</p>
+
+<p><i>May 28, 1910</i>&mdash;G. Curtiss, with Curtiss biplane,
+starts from Albany at 7.03 <small>A. M.</small>, flies to Poughkeepsie
+in 1 hour and 21 minutes (70 miles).
+Leaves Poughkeepsie at 9.24 <small>A. M.</small>, flies to Spuyten
+Duyvil in 1 hour and 11 minutes (67 miles).
+Rises again at 11.45, flies over New York,
+landing on Governor’s Island at 12.03 <small>P. M.</small>
+Wins prize of $10,000 given by the New York
+<i>World</i>.</p>
+
+<p><i>June 2, 1910</i>&mdash;Rolls, with Short-Wright biplane,
+leaves Dover at 6.30 <small>P. M.</small>, crosses Channel to
+French coast near Calais (7.15 <small>P. M.</small>), without
+landing re-crosses Channel to Dover, flies over
+harbor, circles Dover Castle, and lands at 8.10
+<small>P. M.</small> Wins second Ruinart prize of £80.</p>
+
+<p><i>June 14, 1910</i>&mdash;Brookins, with Wright biplane, at
+Indianapolis, reaches height of 4,380 feet.
+(World’s record.)</p>
+
+<p><i>June 25, 1910</i>&mdash;In Italian Parliament 25 million
+lire (about $5,000,000) voted for aviation in the
+extraordinary estimates of the Ministry of War.</p>
+
+<p><i>June 26, 1910</i>&mdash;Dickson, with Farman biplane, at
+Rouen, wins total distance prize of £2,000 and
+<span class="pagenum" id="Page_444">444</span>
+the £400 for longest unbroken flight. Distance
+flown, 466 miles.</p>
+
+<p><i>June 27, 1910</i>&mdash;M. de Lesseps, with Bleriot monoplane,
+flies over Montreal for 49 minutes, covering
+about 30 miles at height generally of 2,000
+feet.</p>
+
+<p><i>July 6, 1910</i>&mdash;First German military aeroplane
+makes maiden cross-country flight over Doeberitz.</p>
+
+<p><i>July 26, 1910</i>&mdash;M. de Lesseps, with Bleriot monoplane,
+starting from Ile de Gros Bois in the St.
+Lawrence, makes trip of 40 miles in 37 minutes.</p>
+
+<p><i>August 1, 1910</i>&mdash;Henry Farman takes up three passengers
+at Mourmelon for 1 hour and 4 minutes.</p>
+
+<p><i>August 5, 1910</i>&mdash;Chavez, with Bleriot monoplane,
+attains height of 5,750 feet. World’s record.</p>
+
+<p><i>August 7, 1910</i>&mdash;Lieutenants Cammerman and Villerme
+fly together from Mourmelon to Nancy,
+125 miles in 2½ hours, with a Farman biplane.</p>
+
+<p><i>August 11, 1910</i>&mdash;Drexel, with Bleriot monoplane,
+at Lanark, beats the world’s record for height,
+rising 6,600 feet.</p>
+
+<p><i>August 27, 1910</i>&mdash;First wireless telegram from a
+flying aeroplane, sent by McCurdy from a Curtiss
+machine in the air, at Atlantic City, N. J.
+<span class="pagenum" id="Page_445">445</span>
+The sending key was attached to the steering
+wheel.</p>
+
+<p><i>August 28, 1910</i>&mdash;Dufaux, with biplane constructed
+by himself, flies over Lake Geneva, wins prize of
+£200 offered by Swiss Aero Club.</p>
+
+<p><i>August 29, 1910</i>&mdash;Breguet, with Breguet monoplane,
+makes a flight at Lille, France, carrying five passengers,
+establishing world’s record for passenger
+flight.</p>
+
+<p><i>August 29, 1910</i>&mdash;Morane, with Bleriot monoplane,
+at Havre, beats world’s altitude record, reaches
+height of 7,166 feet.</p>
+
+<p><i>September 2, 1910</i>&mdash;Mlle. Hélène Dutrieux flies
+with a passenger from Ostend to Bruges, Belgium,
+and back to Ostend. At Bruges she circled
+around the famous belfry at a height of
+1,300 feet, the chimes pealing in honor of the
+feat&mdash;the most wonderful flight so far accomplished
+by a woman.</p>
+
+<p><i>September 3, 1910</i>&mdash;M. Bielovucci lands at Bordeaux,
+France, having made the trip from Paris,
+366 miles, inside of 48 hours. The actual time
+in the air was 7 hours 6 minutes. Strong head
+winds blew him backward, forcing a landing
+three times on the way. This is the fourth longest
+<span class="pagenum" id="Page_446">446</span>
+cross-country flight on record, and makes the
+world’s record for sustained speed over a long
+distance.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_446.jpg" alt="" />
+<p class="caption">Mlle. Hélène Dutrieux.</p></div>
+
+<blockquote>
+
+<p><i>September 4, 1910</i>&mdash;Morane, at Havre, rises to
+height of 8,469 feet.</p>
+
+<p><i>September 7, 1910</i>&mdash;Weyman, with Farman biplane,
+flies from Buc in attempt to reach the top of the
+Puy-de-Dôme, lands at Volvic, 5 miles from his
+<span class="pagenum" id="Page_447">447</span>
+destination. Establishes world’s record for flight
+with passenger, having covered 139 miles without
+landing.</p>
+
+<p><i>September 28, 1910</i>&mdash;Chavez crosses the Alps on a
+Bleriot monoplane from Brigue, in Switzerland,
+to Domodossola, in Italy, flying over the Simplon
+Pass.</p>
+
+<p><i>October 1, 1910</i>&mdash;Henri Wynmalen, of Holland, with
+a biplane at Mourmelon, France, rises to a height
+of 9,121 feet, making a new world’s record for
+altitude.</p>
+
+<p><i>October 4, 1910</i>&mdash;Maurice Tabuteau recrossed the
+Pyrenees, in his return trip from San Sebastian
+to Biarritz, without accident or marked incident.</p>
+
+<p><i>October 5, 1910</i>&mdash;Leon Morane, the winner of nearly
+all the contests in the English meets for 1910,
+fell with his monoplane at Boissy St. Leger, during
+a contest for the Michelin cup, and was seriously
+injured.</p>
+
+<p><i>October 8, 1910</i>&mdash;Archibald Hoxsey, with a biplane,
+makes the longest continuous aeroplane flight recorded
+in America, between Springfield, Ill., and
+St. Louis, Mo.&mdash;104 miles.</p>
+
+<p><i>October 12, 1910</i>&mdash;Alfred Leblanc, with monoplane,
+at St. Louis, flies 13 miles in 10 minutes, a speed
+<span class="pagenum" id="Page_448">448</span>
+of 78 miles per hour. It was not officially recorded,
+as a part of the distance was outside of
+the prescribed course.</p>
+
+<p><i>October 14, 1910</i>&mdash;Grahame-White flies from the
+Bennings Race Track 6 miles across the Potomac
+River to the Capitol at Washington, circles the
+dome, and then circles the Washington Monument,
+and finally alights with precision in Executive
+Street, between the Executive Offices and the
+building of the State, Army, and Navy Departments.
+After a brief call, he rose from the narrow
+street&mdash;but 20 feet wider than his biplane&mdash;and
+returned to the race track without untoward
+incident.</p>
+
+<p><i>October 16, 1910</i>&mdash;Wynmalen flies from Paris to
+Brussels, and returns, with one passenger, within
+the elapsed time of 27 hours 50 minutes, winning
+two prizes amounting to $35,000. The distance
+is 350 miles, and the actual time in the air was
+15 hours 38 minutes.</p>
+
+<p><i>October 25, 1910</i>&mdash;J. Armstrong Drexel, with monoplane,
+at Belmont Park, L. I., rises to height of
+7,105 feet, breaking previous records, and surpassing
+his own record of 6,600 feet, made at
+Lanark, Scotland.
+<span class="pagenum" id="Page_449">449</span></p>
+
+<p><i>October 26, 1910</i>&mdash;Ralph Johnstone, in biplane, at
+Belmont Park, rises to the height of 7,313 feet,
+through sleet and snow, breaking the new American
+record made by Drexel the day before.</p>
+
+<p><i>October 27, 1910</i>&mdash;Johnstone, with biplane, at Belmont
+Park, rises to height of 8,471 feet, surpassing
+his own record of the day before and establishing
+a new American record. The feat was
+performed in a gale blowing nearly 60 miles per
+hour, and the aviator was carried 55 miles away
+from his starting point before he landed.</p>
+
+<p><i>October 28, 1910</i>&mdash;Tabuteau, with biplane, at
+Etampes, France, makes a new world’s endurance
+record of 6 hours’ continuous flight, covering
+a distance of 289 miles.</p>
+
+<p><i>October 29, 1910</i>&mdash;Grahame-White, with monoplane,
+at Belmont Park, wins the International speed
+race over the distance of 62.1 miles, in 1 hour
+1 minute 4⅗ seconds.</p>
+
+<p><i>October 29, 1910</i>&mdash;Leblanc, with monoplane, at Belmont
+Park, makes a new world’s record for speed,
+reaching 70 miles per hour during the International
+speed race. Through a lack of fuel he lost
+the race to Grahame-White, after covering 59
+miles in 52 minutes.
+<span class="pagenum" id="Page_450">450</span></p>
+
+<p><i>October 30, 1910</i>&mdash;John B. Moisant, with monoplane,
+wins the race from Belmont Park around
+the Statue of Liberty in New York harbor, and
+the prize of $10,000. The distance is about 34
+miles, and Moisant covered it in 34 minutes 39
+seconds.</p>
+
+<p><i>October 30, 1910</i>&mdash;James Radley, with monoplane,
+at Belmont Park, wins the cross-country flight of
+20 miles in 20 minutes 5 seconds.</p>
+
+<p><i>October 31, 1910</i>&mdash;Johnstone, with biplane, at Belmont
+Park, rises to a height of 9,714 feet, breaking
+the previous world’s record, made by Wynmalen
+on October 1.</p>
+
+<p><i>October 31, 1910</i>&mdash;Drexel, with monoplane, racing
+for altitude with Johnstone, reaches a height of
+8,370 feet.</p>
+
+<p><i>October 31, 1910</i>&mdash;Moisant, with monoplane, at
+Belmont Park, wins the two-hour distance race
+with a record of 84 miles. His next nearest
+competitor covered but 57 miles.</p>
+
+<p><i>November 14, 1910</i>&mdash;Eugene Ely, with biplane,
+flew from a staging on the deck of the U. S.
+Cruiser <i>Birmingham</i> 8 miles to the shore near
+the mouth of Chesapeake Bay. The flight was
+intended to end at the Norfolk Navy Yard, but
+<span class="pagenum" id="Page_451">451</span>
+an accident to the propeller at starting forced
+Ely to make directly for the shore.</p>
+
+<p><i>November 17, 1910</i>&mdash;Ralph Johnstone, holder of
+the world’s altitude record of 9,714 feet, was
+killed at Denver, Col., by a fall with his biplane.</p>
+
+<p><i>November 23, 1910</i>&mdash;Drexel, at Philadelphia,
+reaches an altitude of 9,970 feet, passing all
+other altitude records. Coming down he made a
+straight glide of seven miles.</p>
+
+<p><i>December 2, 1910</i>&mdash;Charles K. Hamilton, at Memphis,
+Tenn., flies 4 miles in 3 minutes 1 second, a
+speed of 79.2 miles per hour. This is a new
+world’s record.</p></blockquote>
+
+<p><span class="pagenum" id="Page_452">452</span></p>
+
+<hr class="chap" />
+
+<h2 id="Chapter_XX">Chapter XX.<br />
+
+EXPLANATION OF AERONAUTICAL TERMS.</h2>
+
+<p class="drop"><span class="uppercase">Every</span> development in human progress is
+marked by a concurrent development in language.
+To express the new ideas, new words appear,
+or new meanings are given to words already in use.</p>
+
+<p>As yet, the vocabulary of aeronautics is in the
+same constructive and incomplete state as is the science
+to which it attempts to give voice, and the utmost
+that can be done at this time is to record such
+words and special meanings as are in use in the immediate
+present.</p>
+
+<h3>A</h3>
+
+<blockquote>
+
+<p><i>Adjusting Plane</i>&mdash;A small plane, or surface, at the
+outer end of a wing, by which the lateral (from
+side to side) balance of an aeroplane is adjusted.
+It is not connected with the controlling mechanism,
+as are the ailerons&mdash;nor with any automatic
+device.</p>
+
+<p><i>Aerodrome</i>&mdash;A term used by Professor Langley as
+<span class="pagenum" id="Page_453">453</span>
+a better name for the aeroplane; but latterly it
+has been applied to the buildings in which airships
+are housed, and also in a few instances, as
+a name for the course laid out for aeronautical
+contests.</p>
+
+<p><i>Aerofoil</i>&mdash;Another name for the aeroplane, suggested
+as more accurate, considering that the surfaces
+are not true planes.</p>
+
+<p><i>Aeronef</i>&mdash;Another name for an aeroplane.</p>
+
+<p><i>Aeroplane</i>&mdash;The type of flying machine which is
+supported in the air by a spread of surfaces or
+planes, formerly flat, and therefore truly
+“plane,” but of late more or less curved. Even
+though not absolutely accurate, this term has resisted
+displacement by any other.</p>
+
+<p><i>Aerostat</i>&mdash;A free balloon afloat in the air.</p>
+
+<p><i>Aeronate</i>&mdash;A captive balloon.</p>
+
+<p><i>Aileron</i>&mdash;A small movable plane at the wing-tips, or
+hinged between the main planes, usually at their
+outer ends, operated by the aviator to restore
+the lateral balance of the machine when disturbed.</p>
+
+<p><i id="Air_speed">Air-speed</i>&mdash;The speed of aircraft as related to the
+air in which they are moving; as distinguished
+from <a href="#Land_speed">land-speed</a> (which see).
+<span class="pagenum" id="Page_454">454</span></p>
+
+<p><i>Alighting Gear</i>&mdash;Devices on the under side of the
+aeroplane to take up the jar of landing after
+flight, and at the same time to check the forward
+motion at that moment.</p>
+
+<p><i id="Angle_of_Entry">Angle of Entry</i>&mdash;The angle made by the tangent to
+the curve of the aeroplane surface at its forward
+edge, with the direction, or line, of travel.</p>
+
+<p><i>Angle of Incidence</i>&mdash;The angle made by the chord
+of the arc of a curved “plane,” or by the line of
+a flat plane, with the line of travel.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_454.jpg" alt="" /></div>
+
+<blockquote>
+
+<p><i>Angle of Trail</i>&mdash;The angle made by the tangent to
+the rear edge of a curved plane with the line of
+travel.</p>
+
+<p><i>Apteroid</i>&mdash;A form resembling the “short and
+broad” type of the wings of certain birds&mdash;as
+distinguished from the <a href="#Pterygoid">pterygoid</a> (which see).</p>
+
+<p><i>Arc</i>&mdash;Any part of a circle, or other curved line.
+<span class="pagenum" id="Page_455">455</span></p>
+
+<p><i>Arch</i>&mdash;The curve formed by bending the wings
+downward at the tips, leaving them higher at the
+centre of the machine.</p>
+
+<p><i>Aspect</i>&mdash;The view of the top of an aeroplane as it
+appears when looked down upon from above.</p>
+
+<p><i>Aspiration</i>&mdash;The (hitherto) unexplained tendency
+of a curved surface&mdash;convex side upward&mdash;to
+rise and advance when a stream of air blows
+against its forward edge and across the top.</p>
+
+<p><i>Attitude</i>&mdash;The position of a plane as related to the
+line of its travel; usually expressed by the angle
+of incidence.</p>
+
+<p><i>Automatic Stability</i>&mdash;That stability which is preserved
+by self-acting, or self-adjusting, devices
+which are not under the control of the operator,
+nor a fixed part of the machine, as are the adjusting
+planes.</p>
+
+<p><i>Aviation</i>&mdash;Flying by means of power-propelled
+machines which are not buoyed up in the air, as
+with gas bags.</p>
+
+<p><i>Aviator</i>&mdash;The operator, driver, or pilot of an aeroplane.</p></blockquote>
+
+<h3>B</h3>
+
+<blockquote>
+
+<p><i>Balance</i>&mdash;Equilibrium maintained by the controlling
+mechanism, or by the automatic action of
+<span class="pagenum" id="Page_456">456</span>
+balancing-surfaces&mdash;as distinguished from the
+equilibrium preserved by stabilizing surfaces.</p>
+
+<p><i>Balancing Plane</i>&mdash;The surface which is employed
+either intentionally, or automatically, to restore
+a disturbed balance.</p>
+
+<p><i>Biplane</i>&mdash;The type of aeroplane which has two main
+supporting surfaces or planes, placed one above
+the other.</p>
+
+<p><i>Body</i>&mdash;The central structure of an aeroplane, containing
+the machinery and the passenger space&mdash;as
+distinguished from the wings, or planes, and
+the tail.</p>
+
+<p><i>Brace</i>&mdash;A construction member of the framing of
+aircraft which resists a compression strain in a
+diagonal direction&mdash;as distinguished from a
+“stay,” or “diagonal,” which supports a pulling
+strain; also from a strut which supports a compression
+strain in a vertical direction.</p></blockquote>
+
+<h3>C</h3>
+
+<blockquote>
+
+<p><i>Camber</i>&mdash;The distance from the chord of the curve
+of a surface to the highest point of that curve,
+measured at right angles to the chord.</p>
+
+<p><i>Caster</i>, or <i>Castor</i>, <i>Wheel</i>&mdash;A wheel mounted on an
+upright pivoted shaft placed forward of its axle,
+<span class="pagenum" id="Page_457">457</span>
+so that it swivels automatically to assume the line
+of travel of an aeroplane when landing: used in
+the alighting gear. To be distinguished from a
+fixed wheel, which does not swivel.</p>
+
+<p><i>Cell</i>&mdash;A structure with enclosing sides&mdash;similar to
+a box without top or bottom stood upon one side.
+The vertical walls of the cell give lateral stability,
+and its horizontal walls fore-and-aft stability.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_457.jpg" alt="" />
+<p class="caption">The first Santos-Dumont biplane, constructed of cells.</p></div>
+
+<blockquote>
+
+<p><i>Centre of Gravity</i>&mdash;That point of a body where its
+weight centres. If this point is supported, the
+body rests in exact balance.</p>
+
+<p><i>Centre of Lift</i>&mdash;The one point at which the lifting
+forces of the flying planes might be concentrated,
+and produce the same effect.</p>
+
+<p><i>Centre of Resistance</i>&mdash;The one point at which the
+forces opposing the flight of an air-craft might
+be concentrated, and produce the same result.
+<span class="pagenum" id="Page_458">458</span></p>
+
+<p><i>Centre of Thrust</i>&mdash;The one point at which the forces
+generated by the revolving propellers might be
+concentrated, and produce the same effect.</p>
+
+<p><i>Chassis</i>&mdash;The under-structure or “running-gear” of
+an aeroplane.</p>
+
+<p><i>Chord</i>&mdash;The straight line between the two ends of
+an arc of a circle or other curved line.</p>
+
+<p><i>Compound Control</i>&mdash;A mechanical system by which
+several distinct controls are operated through different
+manipulations of the same lever or steering-wheel.</p>
+
+<p><i>Compression Side</i>&mdash;That side of a plane or propeller
+blade against which the air is compressed&mdash;the
+under surface of a flying plane, and the rear surface
+of a revolving propeller.</p>
+
+<p><i id="Curtain">Curtain</i>&mdash;The vertical surface of a cell&mdash;the wall
+which stands upright.</p></blockquote>
+
+<h3>D</h3>
+
+<blockquote>
+
+<p><i>Deck</i>&mdash;A main aeroplane surface. The term is used
+generally in describing biplanes; as the upper
+deck, and the lower deck; or with aeroplanes of
+many decks.</p>
+
+<p><i>Demountable</i>&mdash;A type of construction which permits
+a machine to be easily taken apart for transportation.
+<span class="pagenum" id="Page_459">459</span></p>
+
+<p><i id="Derrick">Derrick</i>&mdash;A tower-shaped structure in which a
+weight is raised and allowed to fall to give starting
+impetus to an aeroplane.</p>
+
+<p><i>Dihedral</i>&mdash;That form of construction in which the
+wings of an aeroplane start with an upward incline
+at their junction with the body of the machine,
+instead of stretching out on a level.</p>
+
+<p><i>Dirigible</i>&mdash;The condition of being directable, or
+steerable: applied generally to the balloons fitted
+with propelling power, or airships.</p>
+
+<p><i>Double Rudder</i>&mdash;A rudder composed of two intersecting
+planes, one vertical and the other horizontal,
+thus enabling the operator to steer in any direction
+with the one rudder.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_459.jpg" alt="" />
+</div>
+
+<blockquote>
+
+<p><i id="Double_Surfaced">Double-Surfaced</i>&mdash;Planes which are covered with
+fabric on both their upper and lower surfaces,
+thus completely inclosing their frames.</p>
+
+<p><i>Down-Wind</i>&mdash;Along with the wind; in the direction
+in which the wind is blowing.</p>
+
+<p><i>Drift</i>&mdash;The recoil of an aeroplane surface forced
+through the air: also the tendency to float in the
+same direction as the wind.</p></blockquote>
+<p><span class="pagenum" id="Page_460">460</span></p>
+
+<h3>E</h3>
+
+<blockquote>
+
+<p><i>Elevator</i>&mdash;A shorter name for the elevating planes
+or elevating rudder, used for directing the aeroplane
+upward or downward.</p>
+
+<p><i>Ellipse</i>&mdash;An oval figure outlined by cutting a cone
+through from side to side on a plane not parallel
+to its base. Some inventors use the curves of the
+ellipse in forming the wings of aeroplanes. See
+<a href="#Hyperbola">Hyperbola</a> and <a href="#Parabola">Parabola</a>.</p>
+
+<p><i>Entry</i>&mdash;The penetration of the air by the forward
+edge of aircraft surfaces. See <a href="#Angle_of_Entry">Angle of Entry</a>.</p>
+
+<p><i>Equivalent Head Area</i>&mdash;Such an area of flat surface
+as will encounter head resistance equal to
+the total of that of the construction members of
+the framework&mdash;struts, braces, spars, diagonals,
+etc., of the aerial craft.</p></blockquote>
+
+<h3>F</h3>
+
+<blockquote>
+
+<p><i>Feathering</i>&mdash;A form of construction in which
+mounting on hinges, or pivots, permits the surfaces
+to engage the air flatwise in one direction
+and to pass edgewise through it in other directions.</p>
+
+<p><i>Fin</i>&mdash;A fixed vertical stabilizing surface, similar in
+form to the fin on the back of a fish.
+<span class="pagenum" id="Page_461">461</span></p>
+
+<p><i>Fish Section</i>&mdash;A term applied to the lengthwise section
+of an aircraft when the outline resembles the
+general shape of a fish&mdash;blunted in front and
+tapering toward the rear. This form is believed
+to encounter less resistance than any other, in
+passing through the air.</p>
+
+<p><i>Fixed Wheel</i>&mdash;A wheel in a fixed mounting, so that
+it does not swivel as does a caster wheel.</p>
+
+<p><i>Flapping Flight</i>&mdash;Flight by the up-and-down beating
+of wings, similar to the common flight of pigeons.</p>
+
+<p><i>Flexible Propeller</i>&mdash;A propeller in which the blades
+are frames covered more or less loosely with a
+fabric which is in a measure free to adjust its
+form to the compression of the air behind it as it
+revolves.</p>
+
+<p><i>Flying Angle</i>&mdash;The angle of incidence of the main
+surface of an aeroplane when in flight. See
+<a href="#Ground_Angle">Ground Angle</a>.</p>
+
+<p><i id="Footpound">Footpound</i>&mdash;The amount of force required to raise
+one pound to a height of one foot.</p>
+
+<p><i>Fore-and-aft</i>&mdash;From front to rear: lengthwise: longitudinal.</p>
+
+<p><i>Fuselage</i>&mdash;The framework of the body of an aeroplane.</p></blockquote>
+<p><span class="pagenum" id="Page_462">462</span></p>
+
+<h3>G</h3>
+
+<blockquote>
+
+<p><i>Glider</i>&mdash;A structure similar to an aeroplane, but
+without motive power.</p>
+
+<p><i>Gliding</i>&mdash;Flying down a slope of air with a glider,
+or with an aeroplane in which the propelling
+power is cut off.</p>
+
+<p><i>Gliding Angle</i>&mdash;The flattest angle at which a given
+machine will make a perfect glide. This angle
+differs with different machines. The flatter the
+gliding angle the safer the machine.</p>
+
+<p><i id="Ground_Angle">Ground Angle</i>&mdash;The angle of incidence of an aeroplane
+surface when the machine is standing on
+the ground.</p>
+
+<p><i>Guy</i>&mdash;A wire attached to a more or less distant part
+of the structure of any aircraft to prevent spreading.
+Also used to denote controlling wires which
+transmit the movements of the levers.</p>
+
+<p><i>Gyroscopic Action</i>&mdash;The resistance which a rotating
+wheel, or wheel-like construction, exhibits when
+a disturbing force tends to change its plane of rotation.</p></blockquote>
+
+<h3>H</h3>
+
+<blockquote>
+
+<p><i>Hangar</i>&mdash;A structure for the housing of aeroplanes.</p>
+
+<p><i>Head Resistance</i>&mdash;The resistance encountered by a
+surface moving through the air.
+<span class="pagenum" id="Page_463">463</span></p>
+
+<p><i>Heavier-than-air</i>&mdash;A term applied to flying machines
+whose weight is not counterbalanced or buoyed
+up by the lifting power of some gas lighter than
+air; and which weigh more than the volume of
+air displaced.</p>
+
+<p><i>Helicopater</i>&mdash;A type of flying machine in which propellers
+revolving horizontally lift and sustain its
+weight in the air.</p>
+
+<p><i id="Horizontal_Rudder">Horizontal Rudder</i>&mdash;The rudder surface which is
+used to steer an aircraft upward or downward:
+so-called because it lies normally in a position
+parallel to the horizon; that is, level.</p>
+
+<p><i>Horse-power</i>&mdash;An amount of work equivalent to the
+lifting of 33,000 footpounds in one minute. See
+<a href="#Footpound">Footpound</a>.</p>
+
+<p><i id="Hyperbola">Hyperbola</i>&mdash;The outline formed by the cutting of a
+cone by a plane passing one side of its axis at
+such an angle that it would also intersect another
+cone placed apex to apex on the same axis.</p></blockquote>
+
+<h3>K</h3>
+
+<blockquote>
+
+<p><i>Keel</i>&mdash;A framework extending lengthwise under an
+aircraft to stiffen the construction: usually employed
+on airships with elongated gas-bags.</p></blockquote>
+<p><span class="pagenum" id="Page_464">464</span></p>
+
+<h3>L</h3>
+
+<blockquote>
+
+<p><i>Lateral</i>&mdash;From side to side; that is, crossing the
+length fore-and-aft, and generally at right angles
+to it.</p>
+
+<p><i id="Land_speed">Land-speed</i>&mdash;The speed of aircraft as related to objects
+on the ground. See <a href="#Air_speed">Air-speed</a>.</p>
+
+<p><i>Landing Area</i>&mdash;A piece of land specially prepared
+for the alighting of aeroplanes without risk of
+injury.</p>
+
+<p><i>Leeway</i>&mdash;Movement of a machine aside from the intended
+course, due to the lateral drift of the
+whole body of air; measured usually at right angles
+to the course.</p>
+
+<p><i>Lift</i>&mdash;The raising, or sustaining effect of an aeroplane
+surface. It is expressed in the weight thus
+overcome.</p>
+
+<p><i>Lighter-than-air</i>&mdash;A term used to designate aircraft
+which, owing to the buoyancy of the gas attached,
+weigh less than the volume of air which they displace.</p>
+
+<p><i>Longitudinal</i>&mdash;In a lengthwise, or fore-and-aft direction.</p></blockquote>
+
+<h3>M</h3>
+
+<blockquote>
+
+<p><i>Main Plane</i>&mdash;The principal supporting surface of
+an aeroplane. In the biplane, or the multiplane
+<span class="pagenum" id="Page_465">465</span>
+type, it denotes the lowest surface, unless some
+other is decidedly larger.</p>
+
+<p><i>Main Landing Wheels</i>&mdash;Those wheels on the alighting
+gear which take the shock in landing.</p>
+
+<p><i>Mast</i>&mdash;A vertical post or strut giving angular altitude
+to guys or long stays. Also used (erroneously)
+to designate a spar reaching out laterally
+or longitudinally in a horizontal position.</p>
+
+<p><i>Monoplane</i>&mdash;An aeroplane with one main supporting
+surface. A Double Monoplane has two of
+such surfaces set one behind the other (tandem)
+but on the same level.</p>
+
+<p><i>Multiplane</i>&mdash;An aeroplane having several main
+planes, at least more than three (for which there
+is the special name of triplane).</p></blockquote>
+
+<h3>N</h3>
+
+<blockquote>
+
+<p><i>Nacelle</i>&mdash;The framework, or body, of a dirigible
+balloon or airship.</p>
+
+<p><i>Negative Angle of Incidence</i>&mdash;An angle of incidence
+below the line of travel, and therefore expressed
+with a minus sign. Surfaces bent to certain
+curves fly successfully at negative angles of incidence,
+and exhibit a comparatively large lift.</p></blockquote>
+<p><span class="pagenum" id="Page_466">466</span></p>
+
+<h3>O</h3>
+
+<blockquote>
+
+<p><i>Ornithopter</i>&mdash;A type of flying machine with wing
+surfaces which are designed to raise and sustain
+the machine in the air by flapping.</p></blockquote>
+
+<h3>P</h3>
+
+<blockquote>
+
+<p><i>Panel</i>&mdash;Another name for <a href="#Curtain">Curtain</a>&mdash;which see.</p>
+
+<p><i id="Parabola">Parabola</i>&mdash;The form outlined when a cone is cut by
+a plane parallel to a line drawn on its surface
+from its apex to its base. Declared to be the correct
+scientific curve for aeroplane surfaces, but
+not so proven, as yet.</p>
+
+<p><i>Pilot</i>&mdash;A term widely used for an operator, or
+driver, of any form of aircraft.</p>
+
+<p><i id="pitch">Pitch</i>&mdash;The distance which a propeller would progress
+during one revolution, if free to move in
+a medium which permitted no <a href="#Slip">slip</a> (which see);
+just as the thread of a bolt travels in the groove
+of its nut.</p>
+
+<p><i>Plane</i>&mdash;Speaking with exactness, a flat spread of
+surface; but in aeronautics it includes also the
+curved sustaining surfaces of aeroplanes.</p>
+
+<p><i>Polyplane</i>&mdash;Another term for Multiplane.</p>
+
+<p><i id="Port">Port</i>&mdash;The left-hand side of an aircraft, as one faces
+forward. See <a href="#Starboard">Starboard</a>.
+<span class="pagenum" id="Page_467">467</span></p>
+
+<p><i>Projected Area</i>&mdash;The total area of an irregular
+structure as projected upon a flat surface; like
+the total area of the shadow of an object cast
+by the sun upon a plane fixed at right angles to
+its rays.</p>
+
+<p><i>Propeller Reaction</i>&mdash;A force produced by a single
+revolving propeller, which tends to revolve the
+machine which it is driving, in the contrary direction.
+This is neutralized in various ways in
+the machines driven by single propellers. Where
+two propellers are used it is escaped by arranging
+them to move in opposite directions.</p></blockquote>
+
+<div class="figcenter">
+<img src="images/i_467.jpg" alt="" />
+<p class="caption">A pterygoid plane.</p></div>
+
+<blockquote>
+
+<p><i id="Pterygoid">Pterygoid</i>&mdash;That type of the wings of birds which
+is long and narrow&mdash;as distinguished from the
+apteroid type.</p>
+
+<p><i>Pylon</i>&mdash;A tower-shaped structure used as a <a href="#Derrick">derrick</a>
+(which see); also for displaying signals to aeronauts.</p></blockquote>
+
+<h3>R</h3>
+
+<blockquote>
+
+<p><i id="Radial_spoke">Radial Spoke</i>&mdash;A wire spoke extending from the hub
+of an alighting wheel straight outward from the
+<span class="pagenum" id="Page_468">468</span>
+centre to the rim of the wheel. See <a href="#Tangent_Spoke">Tangent
+Spoke</a>.</p>
+
+<p><i>Rarefaction Side</i>&mdash;A correct term for the incorrect
+“vacuum side,” so-called. The side opposite the
+compression side: the forward side of a revolving
+propeller blade, or the upper side of a flying
+surface, or the side of a rudder-surface turned
+away from the wind.</p>
+
+<p><i>Reactive Stratum</i>&mdash;The layer of compressed air beneath
+a moving aeroplane surface, or behind a
+moving propeller blade.</p>
+
+<p><i>Rib</i>&mdash;The smaller construction members used in
+building up surfaces. Generally they run fore-and-aft,
+crossing the spars or wing-bars at right
+angles, and they are bent to form the curve of the
+wings or planes.</p>
+
+<p><i>Rising Angle</i>&mdash;Technically, the steepest angle at
+which any given aeroplane will rise into the air.</p>
+
+<p><i>Rudder</i>&mdash;A movable surface by which the aeronaut
+is enabled to steer his craft in a desired direction.
+See <a href="#Horizontal_Rudder">Horizontal Rudder</a> and <a href="#Vertical_Rudder">Vertical Rudder</a>.</p>
+
+<p><i>Runner</i>&mdash;A construction similar to the runners of a
+sleigh, used for alighting on some machines, instead
+of the wheel alighting gear; a skid.</p></blockquote>
+<p><span class="pagenum" id="Page_469">469</span></p>
+
+<h3>S</h3>
+
+<blockquote>
+
+<p><i>Screw</i>&mdash;Another term for propeller; properly, screw-propeller.</p>
+
+<p><i>Single-surfaced</i>&mdash;A term used to designate wings or
+planes whose frames are covered with fabric only
+on the upper side. See <a href="#Double_Surfaced">Double-Surfaced</a>.</p>
+
+<p><i>Skid</i>&mdash;Another name for runner.</p>
+
+<p><i>Skin Friction</i>&mdash;The retarding effect of the adherence
+of the air to surfaces moving rapidly
+through it. It is very slight with polished surfaces,
+and in case of slow speeds is entirely negligible.</p>
+
+<p><i id="Slip">Slip</i>&mdash;The difference between the actual progress of
+a moving propeller, and the theoretical progress
+expressed by its pitch. It is much greater in
+some propellers than in others, due to the “churning”
+of the air by blades of faulty design and
+construction.</p>
+
+<p><i>Soaring Flight</i>&mdash;The sailing motion in the air
+achieved by some of the larger birds without the
+flapping of their wings. It is to be distinguished
+from gliding in that it is in an upward direction.
+Soaring has never been satisfactorily explained,
+and is considered to be the secret whose discovery
+<span class="pagenum" id="Page_470">470</span>
+will bring about the largest advance in the navigation
+of the air.</p>
+
+<p><i>Spar</i>&mdash;A stick of considerable length used in the
+framing of the body of aeroplanes, or as the long
+members in wing structures.</p>
+
+<p><i>Stabilize</i>&mdash;To maintain balance by the automatic
+action of adjunct surfaces, as distinguished from
+the intentional manipulation of controlling devices.</p>
+
+<p><i>Stabilizer</i>&mdash;Any surface whose automatic action
+tends to the maintaining of balance in the air.</p>
+
+<p><i>Stable Equilibrium</i>&mdash;That equilibrium which is inherent
+in the construction of the machine, and
+does not depend upon automatic or controlling
+balancing devices.</p>
+
+<p><i id="Starboard">Starboard</i>&mdash;The right-hand side of an aircraft as
+one faces forward. See <a href="#Port">Port.</a></p>
+
+<p><i>Starting Area</i>&mdash;An area of ground specially prepared
+to facilitate the starting of aeroplanes into
+flight.</p>
+
+<p><i>Starting Device</i>&mdash;Any contrivance for giving an
+aeroplane a powerful impulse or thrust into the
+air. See <a href="#Derrick">Derrick</a>.</p>
+
+<p><i>Starting Impulse</i>&mdash;The thrust with which an aeroplane
+is started into the air for a flight. Most
+<span class="pagenum" id="Page_471">471</span>
+machines depend upon the thrust of their own
+propellers, the machine being held back by force
+until the engines have worked up to flying
+speed, when it is suddenly released.</p>
+
+<p><i>Starting Rail</i>&mdash;The rail upon which the starting
+truck runs before the aeroplane rises into the air.</p>
+
+<p><i>Starting Truck</i>&mdash;A small vehicle upon which the
+aeroplane rests while it is gaining sufficient impulse
+to take flight.</p>
+
+<p><i>Stay</i>&mdash;A construction member of an aeroplane sustaining
+a pulling strain. It is usually of wire.</p>
+
+<p><i>Straight Pitch</i>&mdash;That type of <a href="#pitch">pitch</a> (which see) in
+a propeller blade in which every cross-section of
+the blade makes the same angle with its axis of
+revolution.</p>
+
+<p><i>Strainer</i>&mdash;Another term for Turnbuckle&mdash;which see.</p>
+
+<p><i>Strut</i>&mdash;An upright, or vertical, construction member
+of an aeroplane sustaining a compression strain;
+as distinguished from a brace which sustains a
+diagonal compression strain.</p>
+
+<p><i>Supplementary Surface</i>&mdash;A comparatively small
+surface used as an adjunct to the large surfaces
+for some special purpose; as, for instance, the
+preserving of balance, or for steering.</p>
+
+<p><i>Sustaining Surface</i>&mdash;The large surfaces of the aeroplane
+<span class="pagenum" id="Page_472">472</span>
+whose rapid movement through the air at
+a slight angle to the horizontal sustains the
+weight of the machine.</p></blockquote>
+
+<h3>T</h3>
+
+<blockquote>
+
+<p><i>Tail</i>&mdash;A rear surface on an aeroplane designed to
+assist in maintaining longitudinal stability. It
+is in use principally on monoplanes, and is often
+so arranged as to serve as a rudder.</p>
+
+<p><i>Tail Wheel</i>&mdash;A wheel mounted under the rear end
+of an aeroplane as a part of the alighting gear.</p>
+
+<p><i>Tangent</i>&mdash;A straight line passing the convex side of
+a curved line, and touching it at one point only.
+The straight line is said to be tangent to the
+curve at the point of contact.</p>
+
+<p><i>Tangential</i>&mdash;In the position or direction of a tangent.</p>
+
+<p><i id="Tangent_Spoke">Tangent Spoke</i>&mdash;A wire spoke extending from the
+outer edge of the hub of a wheel along the line
+of a tangent until it touches the rim. Its position
+is at right angles to the course of a <a href="#Radial_spoke">radial
+spoke</a> (which see) from the same point on the
+hub.</p>
+
+<p><i>Tie</i>&mdash;A construction member connecting two points
+with a pulling strain.
+<span class="pagenum" id="Page_473">473</span></p>
+
+<p><i>Tightener</i>&mdash;A device for taking up the slack of a
+stay, or tie; as the turnbuckle.</p>
+
+<p><i>Tractor Propeller</i>&mdash;A propeller placed in front, so
+that it pulls the machine through the air, instead
+of pushing, or thrusting, it from behind.</p>
+
+<p><i>Triplane</i>&mdash;An aeroplane with three main surfaces,
+or decks, placed in a tier, one above another.</p>
+
+<p><i>Turnbuckle</i>&mdash;A device with a nut at each end, of
+contrary pitch, so as to take a right-hand screw
+at one end, and a left-hand screw at the other;
+used for drawing together, or toward each other
+the open ends of a stay, or tie.</p></blockquote>
+
+<h3>U</h3>
+
+<blockquote>
+
+<p><i>Uniform Pitch</i>&mdash;That varying pitch in a propeller
+blade which causes each point in the blade to move
+forward in its own circle the same distance in
+one revolution.</p>
+
+<p><i>Up-wind</i>&mdash;In a direction opposite to the current of
+the wind; against the wind; in the teeth of the
+wind.</p></blockquote>
+
+<h3>V</h3>
+
+<blockquote>
+
+<p><i id="Vertical_Rudder">Vertical Rudder</i>&mdash;A rudder for steering toward
+right or left; so called because its surface occupies
+normally a vertical position.</p></blockquote>
+<p><span class="pagenum" id="Page_474">474</span></p>
+
+<h3>W</h3>
+
+<blockquote>
+
+<p><i>Wake</i>&mdash;The stream of disturbed air left in the rear
+of a moving aircraft, due mainly to the slip of the
+propeller.</p>
+
+<p><i>Wash</i>&mdash;The air-currents flowing out diagonally from
+the sides of a moving aeroplane.</p>
+
+<p><i>Wing Bar</i>&mdash;The larger construction members of a
+wing, running from the body outward to the tips.
+The ribs are attached to the wing bars, usually
+at right angles.</p>
+
+<p><i>Wing Plan</i>&mdash;The outline of the wing or main plane
+surface as viewed from above.</p>
+
+<p><i>Wing Section</i>&mdash;The outline of the wing structure of
+an aeroplane as it would appear if cut by a plane
+passing through it parallel to the longitudinal
+centre of the machine.</p>
+
+<p><i>Wing Skid</i>&mdash;A small skid, or runner, placed under
+the tip of the wings of an aeroplane, to prevent
+damage in case of violent contact with the
+ground.</p>
+
+<p><i>Wing Tip</i>&mdash;The extreme outer end of a wing or
+main plane.</p>
+
+<p><i>Wing Warping</i>&mdash;A controlling device for restoring
+disturbed lateral balance by the forcible pulling
+down or pulling up of the tips of the wings, or of
+<span class="pagenum" id="Page_475">475</span>
+the outer ends of the main surface of the aeroplane.</p>
+
+<p><i>Wing Wheel</i>&mdash;A small wheel placed under the outer
+end of a wing or main plane to prevent contact
+with the ground. An improvement on the wing
+skid.</p></blockquote>
+
+<h3>THE END</h3>
+
+<div class="transnote">
+<h3>Transcriber’s Note:</h3>
+
+<p>Inconsistent spelling and hyphenation are as in the original.</p>
+</div>
+
+
+
+
+
+
+
+
+<pre>
+
+
+
+
+
+End of the Project Gutenberg EBook of How it Flies or, Conquest of the Air, by 
+Richard Ferris
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+</pre>
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+</body>
+</html>
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author	nfenwick <nfenwick@pglaf.org>	2025-02-07 13:20:44 -0800
committer	nfenwick <nfenwick@pglaf.org>	2025-02-07 13:20:44 -0800
commit	331a9bfa7bf69921cea33243c673f01725dd9ee3 (patch)
tree	9bdf0f09a310aa1117b52c46907a819a540e5218