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“When will man cease to crawl in the depths to live in the azure
and quiet of the sky?”
To this question of Camille Flammarion’s the answer is easy. It
will be when the progress of mechanics has enabled us to solve the problem of
aviation. And in a few years—as we can foresee—a more practical
utilization of electricity will do much towards that solution.
In 1783, before the Montgolfier brothers had built their fire-balloon,
and Charles, the physician, had devised his first aerostat, a few adventurous
spirits had dreamt of the conquest of space by mechanical means. The first
inventors did not think of apparatus lighter than air, for that the science of
their time did not allow them to imagine. It was to contrivances heavier than
air, to flying machines in imitation of the birds, that they trusted to realize
aerial locomotion.
This was exactly what had been done by that madman Icarus, the son of
Daedalus, whose wings, fixed together with wax, had melted as they approached
the sun.
But without going back to mythological times, without dwelling on
Archytas of Tarentum, we find, in the works of Dante of Perugia, of Leonardo da
Vinci and Guidotti, the idea of machines made to move through the air. Two
centuries and a half afterwards inventors began to multiply. In 1742 the
Marquis de Bacqueville designed a system of wings, tried it over the Seine, and
fell and broke his arm. In 1768 Paucton conceived the idea of an apparatus with
two screws, suspensive and propulsive. In 1781 Meerwein, the architect of the
Prince of Baden, built an orthopteric machine, and protested against the
tendency of the aerostats which had just been invented. In 1784 Launoy and
Bienvenu had maneuvered a helicopter worked by springs. In 1808 there were the
attempts at flight by the Austrian Jacques Degen. In 1810 came the pamphlet by
Denian of Nantes, in which the principles of “heavier than air” are
laid down. From 1811 to 1840 came the inventions and researches of Derblinger,
Vigual, Sarti, Dubochet, and Cagniard de Latour. In 1842 we have the Englishman
Henson, with his system of inclined planes and screws worked by steam. In 1845
came Cossus and his ascensional screws. In 1847 came Camille Vert and his
helicopter made of birds’ wings. in 1852 came Letur with his system of
guidable parachutes, whose trial cost him his life; and in the same year came
Michel Loup with his plan of gliding through the air on four revolving wings.
In 1853 came Béléguic and his aeroplane with the traction screws,
Vaussin-Chardannes with his guidable kite, and George Cauley with his flying
machines driven by gas. From 1854 to 1863 appeared Joseph Pline with several
patents for aerial systems. Bréant, Carlingford, Le Bris, Du Temple, Bright,
whose ascensional screws were left-handed; Smythies, Panafieu, Crosnier,
&c. At length, in 1863, thanks to the efforts of Nadar, a society of
“heavier than air” was founded in Paris. There the inventors could
experiment with the machines, of which many were patented. Ponton
d’Amécourt and his steam helicopter, La Landelle and his system of
combining screws with inclined planes and parachutes, Louvrié and his
aeroscape, Esterno and his mechanical bird, Groof and his apparatus with wings
worked by levers. The impetus was given, inventors invented, calculators
calculated all that could render aerial locomotion practicable. Bourcart, Le
Bris, Kaufmann, Smyth, Stringfellow, Prigent, Danjard, Pomés and De la Pauze,
Moy, Pénaud, Jobert, Haureau de Villeneuve, Achenbach, Garapon, Duchesne,
Danduran, Pariesel, Dieuaide, Melkiseff, Forlanini, Bearey, Tatin, Dandrieux,
Edison, some with wings or screws, others with inclined planes, imagined,
created, constructed, perfected, their flying machines, ready to do their work,
once there came to be applied to thereby some inventor a motor of adequate
power and excessive lightness.
This list may be a little long, but that will be forgiven, for it is
necessary to give the various steps in the ladder of aerial locomotion, on the
top of which appeared Robur the Conqueror. Without these attempts, these
experiments of his predecessors, how could the inquirer have conceived so
perfect an apparatus? And though he had but contempt for those who obstinately
worked away in the direction of balloons, he held in high esteem all those
partisans of “heavier than air,” English, American, Italian,
Austrian, French—and particularly French—whose work had been
perfected by him, and led him to design and then to build this flying engine
known as the “Albatross,” which he was guiding through the currents
of the atmosphere.
“The pigeon flies!” had exclaimed one of the most persistent
adepts at aviation.
“They will crowd the air as they crowd the earth!” said one
of his most excited partisans.
“From the locomotive to the aeromotive!” shouted the
noisiest of all, who had turned on the trumpet of publicity to awaken the Old
and New Worlds.
Nothing, in fact, is better established, by experiment and calculation,
than that the air is highly resistant. A circumference of only a yard in
diameter in the shape of a parachute can not only impede descent in air, but
can render it isochronous. That is a fact.
It is equally well known that when the speed is great the work of the
weight varies in almost inverse ratio to the square of the speed, and therefore
becomes almost insignificant.
It is also known that as the weight of a flying animal increases, the
less is the proportional increase in the surface beaten by the wings in order
to sustain it, although the motion of the wings becomes slower.
A flying machine must therefore be constructed to take advantage of
these natural laws, to imitate the bird, “that admirable type of aerial
locomotion,” according to Dr. Marcy, of the Institute of France.
In short the contrivances likely to solve the problem are of three
kinds:—
1. Helicopters or spiralifers, which are simply screws with vertical
axes.
2. Ornithopters, machines which endeavour to reproduce the natural
flight of birds.
3. Aeroplanes, which are merely inclined planes like kites, but towed or
driven by screws.
Each of these systems has had and still has it partisans obstinately
resolved to give way in not the slightest particular. However, Robur, for many
reasons, had rejected the two first.
The ornithopter, or mechanical bird, offers certain advantages, no
doubt. That the work and experiments of M. Renard in 1884 have sufficiently
proved. But, as has been said, it is not necessary to copy Nature servilely.
Locomotives are not copied from the hare, nor are ships copied from the fish.
To the first we have put wheels which are not legs; to the second we have put
screws which are not fins. And they do not do so badly. Besides, what is this mechanical
movement in the flight of birds, whose action is so complex? Has not Doctor
Marcy suspected that the feathers open during the return of the wings so as to
let the air through them? And is not that rather a difficult operation for an
artificial machine?
On the other hand, aeroplanes have given many good results. Screws
opposing a slanting plane to the bed of air will produce an ascensional
movement, and the models experimented on have shown that the disposable weight,
that is to say the weight it is possible to deal with as distinct from that of
the apparatus, increases with the square of the speed. Herein the aeroplane has
the advantage over the aerostat even when the aerostat is furnished with the
means of locomotion.
Nevertheless Robur had thought that the simpler his contrivance the
better. And the screws—the Saint Helices that had been thrown in his
teeth at the Weldon Institute—had sufficed for all the needs of his
flying machine. One series could hold it suspended in the air, the other could
drive it along under conditions that were marvelously adapted for speed and
safety.
If the ornithopter—striking like the wings of a bird—raised
itself by beating the air, the helicopter raised itself by striking the air
obliquely, with the fins of the screw as it mounted on an inclined plane. These
fins, or arms, are in reality wings, but wings disposed as a helix instead of
as a paddle wheel. The helix advances in the direction of its axis. Is the axis
vertical? Then it moves vertically. Is the axis horizontal? Then it moves
horizontally.
The whole of Robur’s flying apparatus depended on these two
movements, as will be seen from the following detailed description, which can
be divided under three heads—the platform, the engines of suspension and
propulsion, and the machinery.
Platform.—This was a framework a hundred feet long and twelve
wide, a ship’s deck in fact, with a projecting prow. Beneath was a hull
solidly built, enclosing the engines, stores, and provisions of all sorts,
including the watertanks. Round the deck a few light uprights supported a wire
trellis that did duty for bulwarks. On the deck were three houses, whose
compartments were used as cabins for the crew, or as machine rooms. In the
center house was the machine which drove the suspensory helices, in that
forward was the machine that drove the bow screw, in that aft was the machine
that drove the stern screw. In the bow were the cook’s galley and the
crew’s quarters; in the stern were several cabins, including that of the
engineer, the saloon, and above them all a glass house in which stood the
helmsman, who steered the vessel by means of a powerful rudder. All these
cabins were lighted by port-holes filled with toughened glass, which has ten
times the resistance of ordinary glass. Beneath the hull was a system of
flexible springs to ease off the concussion when it became advisable to land.
Engines of suspension and propulsion.—Above the deck rose
thirty-seven vertical axes, fifteen along each side, and seven, more elevated,
in the centre. The “Albatross” might be called a clipper with
thirty-seven masts. But these masts instead of sails bore each two horizontal
screws, not very large in spread or diameter, but driven at prodigious speed.
Each of these axes had its own movement independent of the rest, and each
alternate one spun round in a different direction from the others, so as to
avoid any tendency to gyration. Hence the screws as they rose on the vertical
column of air retained their equilibrium by their horizontal resistance.
Consequently the apparatus was furnished with seventy-four suspensory screws,
whose three branches were connected by a metallic circle which economized their
motive force. In front and behind, mounted on horizontal axes, were two
propelling screws, each with four arms. These screws were of much larger
diameter than the suspensory ones, but could be worked at quite their speed. In
fact, the vessel combined the systems of Cossus, La Landelle, and Ponton
d’Amécourt, as perfected by Robur. But it was in the choice and application
of his motive force that he could claim to be an inventor.
Machinery.—Robur had not availed himself of the vapor of water or
other liquids, nor compressed air and other mechanical motion. He employed
electricity, that agent which one day will be the soul of the industrial world.
But he required no electro-motor to produce it. All he trusted to was piles and
accumulators. What were the elements of these piles, and what were the acids he
used, Robur only knew. And the construction of the accumulators was kept
equally secret. Of what were their positive and negative plates? None can say.
The engineer took good care—and not unreasonably—to keep his secret
unpatented. One thing was unmistakable, and that was that the piles were of
extraordinary strength; and the accumulators left those of
Faure-Sellon-Volckmar very far behind in yielding currents whose ampères ran
into figures up to then unknown. Thus there was obtained a power to drive the
screws and communicate a suspending and propelling force in excess of all his
requirements under any circumstances.
But—it is as well to repeat it—this belonged entirely to
Robur. He kept it a close secret. And, if the president and secretary of the
Weldon Institute did not happen to discover it, it would probably be lost to
humanity.
It need not be shown that the apparatus possessed sufficient stability.
Its center of gravity proved that at once. There was no danger of its making
alarming angles with the horizontal, still less of its capsizing.
And now for the metal used by Robur in the construction of his
aeronef—a name which can be exactly applied to the
“Albatross.” What was this material, so hard that the bowie-knife
of Phil Evans could not scratch it, and Uncle Prudent could not explain its
nature? Simply paper!
For some years this fabrication had been making considerable progress.
Unsized paper, with the sheets impregnated with dextrin and starch and squeezed
in hydraulic presses, will form a material as hard as steel. There are made of
it pulleys, rails, and wagon-wheels, much more solid than metal wheels, and far
lighter. And it was this lightness and solidity which Robur availed himself of
in building his aerial locomotive. Everything—framework, hull, houses,
cabins— were made of straw-paper turned hard as metal by compression, and
— what was not to be despised in an apparatus flying at great
heights— incombustible. The different parts of the engines and the screws
were made of gelatinized fiber, which combined in sufficient degree flexibility
with resistance. This material could be used in every form. It was insoluble in
most gases. and liquids, acids or essences, to say nothing of its insulating
properties, and it proved most valuable in the electric machinery of the
“Albatross.”
Robur, his mate Tom Turner, an engineer and two assistants, two
steersman and a cook—eight men all told—formed the crew of the
aeronef, and proved ample for all the maneuvers required in aerial navigation.
There were arms of the chase and of war; fishing appliances; electric lights;
instruments of observation, compasses, and sextants for checking the course,
thermometers for studying the temperature, different barometers, some for
estimating the heights attained, others for indicating the variations of
atmospheric pressure; a storm-glass for forecasting tempests; a small library;
a portable printing press; a field-piece mounted on a pivot; breech loading and
throwing a three-inch shell; a supply of powder, bullets, dynamite cartridges;
a cooking-stove, warmed by currents from the accumulators; a stock of
preserves, meats and vegetables sufficient to last for months. Such were the
outfit and stores of the aeronef— in addition to the famous trumpet.
There was besides a light india-rubber boat, insubmersible, which could
carry eight men on the surface of a river, a lake, or a calm sea.
But were there an parachutes in case of accident? No. Robur did not
believe in accidents of that kind. The axes of the screws were independent. The
stoppage of a few would not affect the motion of the others; and if only half
were working, the “Albatross” could still keep afloat in her
natural element.
“And with her,” said Robur to his guests—guests in
spite of themselves—“I am master of the seventh part of the world,
larger than Africa, Oceania, Asia, America, and Europe, this aerial Icarian
sea, which millions of Icarians will one day people.”
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