The electric eel. There are several species inhabiting the water, and which have the power of producing electric discharges by certain portions of their organism. The best known of these are the Torpedo, the Gymnotus, and the Silurus, found in the Nile and the Tiger.
In the Surinam eel, the electric organ goes the whole length of the body along both sides. It is able to give a very severe shock, and is a formidable antagonist when it has attained its full length of 5 or 6 feet.
A. Pilot’s seat and controlling wheel
B. Passenger’s seat
C. Movable flap to facilitate entering the hull
D. Handle, like that of a car, for starting the engine
E. The engine
F. Fuel tanks
G. The propeller.
In July, at Rheims, there was to be the great flying meeting; and Farman had made up his mind to wait for this. Aided by the experience he had gained with the Voisin machine, he had designed a craft which should be generally more efficient and faster in flight, and more quickly responsive to its controls. The biplane he produced, marking as it did a step forward in construction, is a machine that needs description. The general appearance of the craft is indicated by Fig. 46, while an illustration of this type of machine in flight will be found on Plate VII. A feature of the Voisin that Farman discarded was the vertical panel fitted between the main-planes to give sideway stability. An objection to these planes was that they added to the weight of the machine and checked its speed, tending also to drive it from its course should there be a side wind. But in taking away such fixed balancing-planes, Farman had to substitute another device; and what he did was to work upon the same theory as the Wrights had done, and obtain a similar result in a different way. They, it will be remembered, had warped the rear portions of their main-planes. Farman kept his planes rigid, but fitted to their rear extremities four narrow, hinged planes, or flaps, which could be moved up and down and were called ailerons. Their effect was the same as with the Wright wing-warp. When a gust tilted the machine, the pilot drew down the ailerons upon the side that was inclined downward; whereupon the air-pressure, acting upon the drawn-down surfaces, restored the machine to an even keel.
C. Pilot’s seat;
D. Motor and propeller;
E. Petrol tank;
F.F. Hinged balancing-planes, or ailerons;
H.H. Twin vertical rudders;
I. Landing wheels and skid
showing the span of main-planes, elevator, and tail, also the positions of landing gear and pilot’s seat.
Of famous aeroplanes at Rheims, five types stood out by themselves—the Farman, the Voisin, the Wright, the Bleriot, and the Antoinette, all of which have been described. But there was one other, which few people had heard of before it appeared here. This was the Curtiss biplane, built by an American named Glenn H. Curtiss, and engined with a motor which also bore his name. Curtiss had experimented with many power-driven machines—motor-cycles, motor-cars, airships, and aeroplanes—and had won a prize in America with a small, light biplane, and it was a craft of this type—as seen in the figure —that he brought with him to Rheims, his idea being to compete for the speed prize. The machine had a front elevator and tail-planes, according to the practice in biplane construction; but an innovation was the setting of the ailerons midway between the main-planes—a position that will be noted in the sketch; another novelty was the way these ailerons operated. At the pilot’s back, as he sat in his driving seat, was an upright rod with two shoulder-pieces—by means of which, should he shift his body, he could swing the rod from side to side. Wires ran from the rod to the ailerons; and if the pilot leaned over, say, to the right, he drew down the ailerons on the left side of the machine. The merit of such a control was that it was instinctive; that is to say, should the biplane tip down on one side, it was natural for the pilot to lean away from the plane-ends that were sinking; and he operated the ailerons automatically, as he did this, and so brought the machine level again.
B. Pilot’s seat and control-wheel
E. Motor and propeller
F. Tail-plane and rudder.
The Curtiss Biplane making a turn
There needs to be an equipment of spare machines also; and a number of travelling workshops with skilled engineers, which can be rushed from place to place for the repair of damaged craft. A sketch of one of these workshops on wheels, which are vital to the organisation, is seen in the figure
At the beginning of 1909 there were two types of successful aeroplane—the Wright and the Voisin. Bleriot had flown with his monoplane and flown well; but he was still in the process of evolving a practical machine, and several other inventors were in a similar stage. It was the Wright and the Voisin which had proved their worth; and the Wright, as has been said, was the better of the two. Of the Voisin, as flown in 1909, a reproduction is given in the figure. It was a heavier aeroplane than the Wrights’, owing largely to the weight of its alighting gear (250 lbs.) and of its big balancing tail (more than 100 lbs.); hence the necessity for using a 50-h.p. motor, which drove a two-bladed metal propeller at the rate of 1200 revolutions a minute. The Voisin brothers, and other French makers, did not approve of the two-propeller system of the Wrights: they preferred one screw, revolving at high speed. But there was no doubt—at any rate in this stage of aviation—that the Wright method was more efficient than that of the Frenchmen. It was calculated, indeed, that the Wright biplane, when actually in the air, could be driven at an expenditure of only 15 h.p.; whereas the Voisin, even with its 50-h.p. motor running at full speed, had only just enough power to fly.
A. Elevating plane
B. Pilot’s seat
D. Engine and propeller
E. Landing chassis
F. Balancing tail
The Voisin Biplane - top view
A fighting aeroplane
A. Machine-gun projecting from opening in bow
B. Gunner’s position
C. Pilot’s seat
D.D. Side windows for observation
E. Engine and propeller.
A. Enclosed body
B. Driver’s position
C. Steering wheel
D. Foot-controlled throttle lever for engine
E.E. The two sustaining-planes
F. The motor
J. Landing gear.
First probably for mails, and after this for passenger-carrying, will aeroplanes of the future be employed; and they will find a scientific use, too, in exploring remote corners of the earth, and in passing above forests which are now impenetrable. Small, fast machines, much cheaper than those of to-day, will be bought also for private use—many of them, as suggested by the figure, having room for only one man within their hulls. Then there will be flying clubs; and to these, after their day’s work, will come a city’s toilers. Through the cheapening of craft, as time goes on, practically all members of the community will experience the joys of flight. Thus, say on a summer’s evening, the doors of the sheds will be pushed aside, and the machines wheeled out and overhauled; then, one by one, these small, fast-moving craft will rise into the air and dart here and there—circling, manœuvring, dipping, and diving.
The difficulty with air-cooling—although it had obvious advantages over water-cooling—was to bring enough air to play upon the surfaces of the cylinders; and it was here that the Gnome won so complete a success. In other engines the cylinders were stationary, and their pistons, moving up and down in the cylinders, turned a crank-shaft to the end of which the propeller was fixed. Therefore the only air the cylinders obtained was what rushed upon them through the speed of the machine in flight. But in the Gnome, instead of the cylinders remaining stationary and the crank-shaft revolving, the cylinders themselves spun round, and the crank-shaft did not move. An illustration of this motor with one end of the crank-chamber removed, so that the piston-rods can be seen, is given in the figure. It will be noted that there are seven cylinders, set in the form of a star, and that the seven piston-rods projecting from them come together upon a single crank-pin, which is attached to the stationary crank-shaft and turns round it. The propeller, instead of being fitted to the crank-shaft, as was the case with other motors, was bolted to a plate upon the engine itself, so that when this turned around its crank-shaft, it carried the propeller with it.
An experimenter who braved this apathy and won his way until he became a constructor of aircraft, was Mr. A. V. Roe. For some time he was an advocate of the triplane form of machine—a craft, that is to say, with three main-planes fitted one above another. The machine with which he obtained flights, although they were very brief, is seen in the figure. Subsequently, however, Mr. Roe adopted the biplane form. His distinction in the pioneer days was that he managed to make his triplane lift into the air and fly a short distance, with the aid of a motor-cycle engine developing no more than 9 h.p.
A.A.A. Three main-planes
C. Four-bladed propeller
D.D.D. Triplane tail
F. Landing gear.
D. Pilot’s seat
E. Landing chassis
F. Combined tail and elevating-planes
The Bleriot Monoplane - top view showing its bird-like shape and the position of the pilot.
At the beginning of 1909 a new monoplane made its appearance in France—a powerful, finely constructed, and very stable machine. It was the Antoinette, designed by a famous engineer, and it was this craft which interested Latham. M. Levavasseur was the designer of it and of a specially lightened motor, first applied to motor-boats, and afterwards to the experimental biplane of M. Santos-Dumont and also to the aeroplane with which Farman first flew. The Antoinette, which M. Levavasseur also fitted with one of his motors, was a large monoplane—far larger than the Bleriot; and built not with the idea of being a fair-weather machine, but to fly in winds. The span of its wings was 46 feet, and they contained 365 square feet of sustaining surface, while the total weight was 1040 lbs.
D. Pilot’s seat and controlling wheel
E.E. Vertical rudders
G. Landing gear.
showing the spread of the planes and tail, and the delicate taper of the long, canoe-shaped body.
A machine that has achieved success, owing to its power of varying speed, is the Sopwith military biplane. Adopting a practice that has become general, its wings are fitted upon what is practically a monoplane body. Tail-planes and rudder are the same as in a monoplane. The top main-plane, as will be seen, is set slightly in advance of the lower. The system is called “staggering”; and the idea is that, by placing the upper plane ahead of the lower, the total lifting power will be increased. It has been proved a disadvantage of the biplane that, when the main-planes are placed one above another, there is a slight loss of lift owing to the fact that, acting upon the air as they do quite close to each other, a certain amount of interference occurs between them—one tending to disturb the air-stream in which the other moves. By “staggering” the two planes this interference is overcome; but some makers regard it as a small consideration, and build their planes in the ordinary way, allowing as large a gap as possible between them. In the Sopwith military machine, engine and propeller are in front of the main-planes; then come the places for pilot and observer. The pilot sits first, and the body of the machine is so high that only his head appears above it, while just in front of his face, to deflect the wind-rush from the propeller, there is a raised section of the hull which acts as a screen. Behind the pilot, sitting in a second opening in the hull, is the observer. He has a view forward, rendered the better by setting back the lower-plane; while at the point at which it joins the body of the machine, immediately below him, this plane is hollowed out, so that he can look directly upon the earth below. Small windows are also fitted upon either side of the hull. Through those in front the pilot may glance when descending from a flight, so as to judge his distance from the ground, while the others are utilised by the observer, as he turns to look from side to side. This biplane, and many others, is balanced against sideway roll by ailerons, and not by warping the wings. Constant warping, such as is necessary in the everyday use of machines, has been declared to strain a plane and render it weak; therefore the use of ailerons is now favoured.
B. Motor, partly hidden by shield
D. Pilot’s seat
E. Observer’s seat
F. Outlook windows in side of hull
I. Landing gear.
The Curtiss Biplane in flight
showing the chassis and the position between the planes of the two ailerons (A.A.).
Another ardent worker in England, and one destined to become famous, was Mr. S. F. Cody. After developing a system of man-lifting kites which the British War Office acquired, he joined the military aircraft factory that had been established at Farnborough. Here, after tests with dirigible balloons, he began the construction of experimental biplanes—all machines of large size. Early in 1909 he made brief flights—the longest being one of about 250 yards. Then, after alterations to his machine, he managed in July to fly a distance of 4 miles. This he increased afterwards to 8 miles; and then on 1st September flew for 1 hour 3 minutes, rising to a height of 300 feet. Cody’s biplane was a very large machine, having 1000 square feet of lifting surface—twice that of the Farman or Voisin. Driving it was an 80-h.p. engine, which operated two propellers on the system used by the Wrights. With its pilot on board the machine weighed 2170 lbs.
A. Elevating-planes and vertical-plane
B. Pilot’s control lever
G. Landing gear
H. Rear skid.
showing the large size of the elevators, the position of the pilot, and the placing of the propellers.
A.A. Ballast bags filled with sand
B. Instruments (such as a statoscope, which shows at any moment whether the balloon is rising or falling; and an altitude meter)
C. Ring by which car is attached to balloon.
Hence there is a type of fast scouting monoplane, in which a pilot can ascend alone, and fly at 100 miles an hour. With such a craft, sweeping rapidly above an enemy’s position, the pilot-observer can return with his information at surprising speed. In the figure an air-scout of this type is seen. The tapering, covered-in body will be observed; this is to reduce wind resistance as the machine rushes through the air. The Gnome engine is, for the same reason, covered by an aluminium shield, which only allows the lower cylinders to project; they must, of course, be exposed in some way to the air, or they would not cool themselves. The landing-carriage has been reduced to its simplest form; this, again, is to reduce wind resistance; and the pilot, sitting deep in the body, shows only his head as the machine flies. Here, again, apart from the greater comfort in being so shielded, the placing of the pilot within the machine spells a lessening of pressure.
B. Motor (partly hidden by shield)
C. Pilot’s seat
D. Sustaining plane
But as airships were built larger, and greater speeds were obtained, it became necessary to strengthen the envelopes with some form of keel; and this led to a type which is known as the semi-rigid, and is developed successfully in France. The figure illustrates an airship of this build. Along the lower side of its envelope is placed a light, rigid framework or keel, and from this is suspended the car which contains engines and crew.
A. Gas-containing envelope
B. Strengthening keel
E. Car carrying engines, propeller, and crew.
A coastal sea-plane, as now planned, is a craft having, say, two engines, each devolving 120 h.p., with a wing span of some 80 feet, and an accommodation in its hull for three men—the pilot, a combatant with a machine-gun, and an observer with an installation of wireless. But types are changing constantly, and the tendency is to build larger craft. A machine weighing a couple of tons is shown, and a novelty in regard to it is that it has wheels upon either side of its boat-shaped car, upon which it can move on land, and which fold upward when it rests upon the water.
A. Hull upon which the machine floats when in the sea
B.B.B. Wheels upon which it may move when on land, and which fold upward when it is on the water
C. Pilot’s controlling wheel
D.D. Main sustaining planes
E. Four-bladed propeller driven by chain-gearing from engine within the hull.
To meet the demand for a purely scouting machine, in which pilot and passenger shall have a clear field for observation, both above and below, a monoplane has been designed which is called the “parasol.” This machine, a Morane-Saulnier, is shown. The two sustaining wings, forming a single surface, are raised above the body so that its occupants have nothing to impede their view earthward; and they can also see above them—an advantage of course in time of war, seeing that an enemy might be hovering overhead
A. Engine and propeller
B. Plane raised above hull
C. Seats for pilot and passenger
When petrol engines became available, they gave an impetus to the building of airships; for, like the aeroplane, the airship needed a motive agent which gives a high power for a low weight. One of the first to use a petrol motor in an airship with success was M. Santos-Dumont, whose name has been mentioned in connection with aeroplanes. He tested small, light airships, driven by petrol engines and two-bladed propellers—as illustrated in figure; and with one of these, on a calm, still day, he flew over Paris and round the Eiffel Tower.
A. Gas envelope
B. Wheeled framework which carried motor, propeller, and pilot’s seat
D. Horizontal rear-plane
The fitting of several motors has been shown to be practical; and it has the obvious advantage that, should one fail while in the air, the other or others will maintain a craft in flight. In such a machine as would fly the Atlantic, for example, it is proposed to fit four motors developing 800 h.p., and to carry a couple of mechanics who would constantly be tending them. Thus, should one engine develop trouble, its repair could be effected without descent, and with no worse result than a temporary fall in speed. In the figure is shown a method by which three Gnome motors may be fitted to a biplane.
A. First engine (a 50-h.p. Gnome)
B. Second engine (which is on the same shaft, but will run independently)
C. Third Gnome engine, also an independent unit
D. Four-bladed propeller (mounted higher than the crank-shaft bearing the engines, and driven by a chain gearing).
A. Lower part of aeroplane’s hull
B. Revolving barrel to which bombs are clipped
D. Releasing mechanism operated by marksman in machine.
Coal-gas superseded hot air in the filling of balloons, the latter being unsatisfactory, seeing that it cooled rapidly and allowed the balloon to descend; the only alternative being to do what some of the first aeronauts did, and burn a fire below the neck of their balloon even when in the air. But the dangers of this were great, seeing that the whole envelope might easily become ignited. With balloons filled with coal-gas long flights were possible, but they had always this disadvantage—the voyagers were at the mercy of the wind, and could not fly in any direction they might choose. If the wind blew from the north then they were driven south, the balloon being a bubble in the air, wafted by every gust. Aeronauts became disgusted with this inability to guide the flight of a balloon, and many quaint controls were tested; such, for example, as the use of a large pair of oars with which the balloonist, sitting in the car of his craft, rowed vigorously in the air.
...it was followed in due course by the use of small steam engines and electric motors, which were made to turn propellers such as are used in aeroplanes. For such experimental craft, the rounded form of gas-container was abandoned and a cigar-shaped envelope adopted, pointed at both ends, which could be more easily driven through the air. An airship of a crude and early type is seen here. It was built by an experimenter named Gifford, and in 1852 it flew at the rate of seven miles an hour.
A. Gas-containing envelope; B. Car suspended below envelope, which carried the aeronaut and a 3-horse-power steam engine; C. Two-bladed propeller driven by the engine; D. Rudder (in the form of a sail) by which the machine could be steered from side to side.
An Airship leaving its shed
Airships, like aeroplanes, are being armed with guns and bombs; and their power of raising weights enables them to carry heavy weapons. Large and highly destructive bombs have been tested in the German airships, being released over the sea and aimed at targets in the form of rafts. Latest-type airships also carry guns in their cars; and the Zeppelins have a platform upon the tops of their hulls, reached by a ladder through the middle of the ship, from which a machine-gun can be fired upward. This is a very necessary precaution, and is intended to frustrate the attack of an aeroplane. It would be the aim of the latter, whenever possible, to manœuvre above its big enemy—as suggested in figure —and drop a bomb upon its hull. Hence the construction of the top platform of the airship, from which her gunners can direct a vigorous fire aloft.
The Simuliidæ, or black flies, are small, dark, or black flies, with a stout body and a hump-back appearance. The antennæ are short but eleven-segmented, the wings broad, without scales or hairs, and with the anterior veins stout but the others very weak. The mouth-parts are fitted for biting.