Fig. 52 exhibits an apparatus patented in 1871 by M. Danjard. This was to consist in parachute-like sails in front and at the rear, between which were to be placed two sustaining aeroplanes, between which again there was to be a pair of vibrating wings, which, in connection with screw, placed behind the car, were to furnish the impulsion. The front parachute was to be triangular in form, and made strong and rigid to cleave the air, while the rear parachute and the two aeroplanes were to be made flexible in the rear, so as to obtain a horizontal thrust from he escaping air compressed at the front. Under the rear parachute there was to be a rudder, to move to the right or to the left, and the machinery and aviators were to be in the central car. No motor is indicated save hand-power, but, of course, any primary motor could be applied if it were only light enough.
FIG. 52 -- DANJARD-- 1871.
The apparatus is not known to have been experimented with. Probably M. Danjard dropped a lot of paper models and found that the arrangement of planes in pairs was more stable than a single aeroplane, and the figure is here given to show a combination which will be seen to have given fair stability in other experiments to be hereafter described.
The next experiment to be mentioned was important and quite successful upon the small scale on which it was tried. Fig. 53 represents an aeroplane with automatic equilibrium, produced in 1871 by M. A. Pénaud who called it his "planophore,"and whose artificial bird and flying screw have already been noticed.
FIG. 53 -- PÉNAUD -- 1871.
The motive power in this aeroplane was, as in his former models, the force of twisted india-rubber threads, fastened to a stick 20 in. long, and rotating a double_vaned screw 8 in. in diameter. The aeroplane, 18 in. across, by a width of 4 in., was fastened to the main stick at about its center, so that, through the leverage of the from end, the center of gravity of the apparatus should be slightly in front of the center of surface of the sustaining aeroplane. The outer ends of the latter were bent upward, so as to furnish lateral stability by a diedral angle, and the longitudinal stability was secured by fastening to the main stick back of the aeroplane, as shown, a small pair of wings or rudders, set at an angle of about 8 pointing below the horizon of the main aeroplane.
This was the important feature of the apparatus, and M. Pénaud not only showed experimentally that it furnished automatic equilibrium, but he also demonstrated26 the mathematical reasons why it should do so, in reestablishing, through the action of the air impinging upon this horizontal rudder set at a fixed angle, any deviation of the aeroplane from the horizontal line of flight. The principle is the same as that of the rear told of the paper aeroplane which has already been described, and the following account of its mode of action was given by Mr. Bennett at the 1874 meeting of the Aeronautical Society of Great Britain:
The center of gravity of he machine is placed a little in front of the center of pressure of the aeroplane, so that it tends to make the model descend an incline; but in so doing it lessens the angle of inclination of the aeroplane, and the speed is increased At the same time the angle of the horizontal rudder is increased, and the pressure of the air on its upper surface causes it to descend; but as the machine tends to turn round its center of gravity, the front part is raised and brought back to the horizontal position. If, owing to the momentum gained during the descent, the machine still tends upward, the angle of the plane is increased, and the speed decreased. The angle of the rudder from the horizontal being reduced, it no longer receives the pressure of air on its superior surface, the weight in front reasserts its power, and the machine descends. Thus, by the alternate action of the weight in front and the rudder behind the plane, the equilibrium is maintained. The machine during flight, owing to the above causes, describes a series of ascents and descents after the manner of a sparrow.
The weight of the entire apparatus was 0.56 oz., of which the rubber absorbed 0.17 oz., or about one-third. The surface was 0.53 sq. ft., so that the proportion was nearly at the rate of 15 sq. ft. per pound, and necessarily gave a slow flight.
The apparatus was publicly exhibited in August, 1871, to a group of members of the French Society of Aerial Navigation, in the garden of the Tuileries, and the model, guided horizontally by a small vertical rudder, not shown on the figure, flew several times in a circle, falling gently to the ground near its starting-point, when the power of the rubber was exhausted. The speed was not quite 12 ft. per second, or about the same as that of insects with the same relative surface in proportion to their weight, and the flight was 131 ft. in 11 seconds, with 240 turns of the rubber.
Subsequently M. Pénaud measured the power consumed in a very ingenious way. He found that with 60 turns of the rubber the apparatus would just hold its own--i.e., hover in the same spot, against a wind of 9 ft. per ,second, and knowing the speed of rotation of the screw, as well as the weight of the apparatus, he deduced the conclusion that the power expended was at the rate of one horse-power for each 81 lbs. of weight, although M. Touche, who has revised the calculations, makes it about three times this amount--a result, of course, quite inferior to those obtained by Professor Langley and by Mr. Maxim, because, perhaps, of the greater proportion of surface to weight.
M. Pénaud was a very ingenious man, and might have accomplished great things in aerial navigation had not his career been cut short prematurely. He was one of the few men who have taken up the subject in his youth, for it is a singular fact that most of the scientific students of this inchoate research are now men of middle age, perhaps past the dread of being considered mentally unsound, but no longer with the ardor and the daring of youth. M. Pénaud however, began before he was 20 years old, by producing his flying screw. He had intended to enter the French Navy, but a painful hip disease had brought him to crutches, and left him no career but that of scientific studies. These he directed to aerial navigation, and during six or seven years of improved health he impetuously investigated and experimented upon the various phases of the problem. Not only did he produce the three forms of apparatus which have been described, almost the first which have practically worked, each flying upon a different principle and all produced by one man, but he took a very active part in the investigations promoted by the French Society for Aerial Navigation; making a scientific balloon ascent, in which he was somewhat injured. designing a plane table for platting the course of balloons, a guide rope break, a delicate barometer, a balloon-valve, a kite without a tail, balanced in the same way as his aeroplane, a form of explosion engine, a programme for experiments on air resistances, one for investigation of flight by instantaneous photography, since--carried out by Professor Marey, etc., etc., towering above his fellow-members in discussions, in a way which must have excited many jealousies; and he also contributed a number of very valuable papers to the Aéronaute in one of which he endeavored to account for the mystery of sailing flight by showing that ascending currents in the wind were not rare, and were quite sufficient to explain all the phenomena.
These labors finally culminated in his taking, in 1876 (in partnership with M. Gauchot a clever mechanician, who had produced an artificial bird), a patent for the apparatus shown in fig. 54, which was to be of sufficient size to carry up two men.
FIG. 54 -- PÉNAUD & GAUCHOT -- 1876.
It was to consist of an aeroplane somewhat in the form of an ellipse, built of a light framework covered both at top and bottom with varnished silk, and stiffened by wire stays radiating from two short masts above and from the car below the aeroplane. The outer ends of the aeroplane were to be flexible, or to be set at a diedral angle, in order to produce lateral stability, and the rear portion was also to be flexible and to bend upward, to produce the longitudinal stability, this being, moreover, provided for by two horizontal rudders, side by side, hinged at the rear, so as to set themselves automatically at the angle required to produce fore-and-aft equilibrium, upon the principle developed in the "planophore." Under these balanced horizontal rudders a vertical rudder was to steer to the right or left. A car, in the shape of a light boat, was to be rigidly attached just under the aeroplane, the steersman standing or sitting at the bow, with his head just above the top of the aeroplane, and protected from the wind by a glass box. Movable legs with rollers and springs were to be let down to get a preliminary run on land, or to alight in a glancing direction.
The motion was to be obtained from two propellers, placed at the front edge of the aeroplane, and rotating in opposite directions; the power to be furnished by a steam engine--although M. Pénaud said frankly that he knew of none in practical operation sufficiently light for his purpose. He believed it ought not to weigh more than 15 to 22 lbs. per horse-power, and hoped to get one constructed within those limits. The engine was so to be located in the car as to bring the center of gravity of the apparatus one-fifth of the distance back of the front edge, and all the steering was to be done by the helmsman through a single lever, which might either be pulled or pushed to work the horizontal rudders, or twisted to work the vertical rudder.
The sustaining surface of the aeroplane was to be proportioned at the rate of about 0,24 sq. ft. per pound of weight, the whole apparatus with two aviators was to weigh 2,640 lbs, and required an engine of 20 to 30 H.P. to fly through the air at 60 miles per hour, with an angle of incidence of 2°.
This apparatus, the result of several years of study by an able man who bestowed very careful thought thereon, was never built. The writer of this does not believe it would have succeeded if it had been experimented with, but valuable data might have been obtained. Aside from the difficulty about a light motive power, a difficulty now almost removed, it may be questioned whether the general form of the aeroplane was the best possible to glide upon the air, and whether the longitudinal equilibrium would have been as well preserved as in M. Pénaud's toy model. If not, then a sustaining surface of only 0.24 sq. ft. per pound would have been exceedingly dangerous. The horizontal rudders, when left to adjust themselves, were expected to regulate the automatic balance, but they were also expected, when actuated by the steersman, to alter the angle of incidence, .in order to cause the apparatus to rise or to fall. Such a change in the angle would necessarily alter the position of the center of pressure, and there was no provision for making a corresponding change in the center of gravity, other than by the displacement of the aviators themselves, or that of the fuel, water, or boiler, which displacement would be nearly impracticable.
This was the weak point, for the pressure being then applied at a point differing from the center of gravity, would act with a leverage upon the apparatus and tilt it either forward or backward longitudinally, so that, had it been experimented with on a practical scale, it might have experienced a forward sheer or a plunge, either from too great an action of the horizontal rudders in rising or in coming down, or, as in the case of poor Le Bris's second experiment, from encounter with a stratum of wind of different horizontal direction than that for which the machine was adjusted.
Perhaps surmising the possibility of some such action, M. Pénaud suggested that the experiments should be conducted over a sheet of water. The apparatus might also have been suspended between two very high masts, or from a captive balloon, but probably the best results would have been obtained by experimenting entirely clear of any restraining supports.
At any rate no funds were forthcoming for the construction of the full-sized machine. M. Pénaud was criticised decried, misrepresented, and all sorts of obstacles arose to prevent the testing of his project. He lost courage and hope, his health gave way, and he died in October, 1880 before he had reached 30 years of age.
He had doubtless done much toward solving the difficult problem of automatic stability in the air, but the French aviators do not seem to accept M. Pénaud's device as a solution of the question of longitudinal equilibrium. They claim that it consumes too much power in the constant readjustment of the stability, and that in a full-sized navigable apparatus it would not act quickly enough to prevent disaster. In September, 1890 M. Hureau de Villeneuve published a paper in the Aéronaute, in which he treats the problem of stability as yet to be solved, and suggests the inverted cone, as exemplified in the parachute of Cocking (which failed simply by reason of faulty construction), and he proposes as a possible solution of the equilibrium in both directions, that the aviating surface shall be made to conform to the development of an inverted cone. That is to say, that its lines, whatever they may be in the ground plan shall in vertical projection follow the development of an inverted cone, placing the center of gravity so as to correspond with the position of the apex, and this he seems to have illustrated with a number of working models by cutting out various forms of birds out of an inverted cone. Pénaud said that his solution was practically the same as that of Sir George Cayley, with whose labors he was not acquainted at the time that he hit upon the device for his "planophore." In his articles in Nicholson's Journal, published in 1809 and 1810 Sir George Cayley shows that the lateral stability is easily secured by placing the wings, either curved or plane, at a slight diedral angle to each other and he lays down the principle, that in order to secure the longitudinal stability: 1. The center of gravity must be made to occupy a position directly under the center of pressure; and 2. The aeroplane requires, to steady it, a rudder in a similar position to the tail in the bird. He then continues:
All these principles upon which the support, steadiness, elevation, depression, and steerage of vessels for aerial navigation depend have been abundantly verified by experiments, both upon a large and small scale. I made a machine having a surface of 300 sq. it., which was accidentally broken before there was an opportunity of trying the effect of the propelling apparatus, but its steerage and steadiness were perfectly proved and it would sail obliquely downward in any direction according to the set of the rudder. Its weight was 56 lbs., and it was loaded with 84 lbs., thus making a total of 140 lbs., or about 2 sq ft. to 1 lb. Even in this state, when any person ran forward in it with his full speed. taking advantage of a gentle breeze in front, it would bear upward so strongly as scarcely to allow him to touch the ground, and would frequently lift him up and convey him several yards together.... It was beautiful to see this noble white bird sail majestically from the top of a hill to any given point of the plain below it, with perfect steadiness and safety, according to the set of its rudder merely by its own weight, descending in an angle of about 8° with the horizon.
A number of very interesting experiments upon the stability of aeroplanes were tried in 1873 and 1874 by Mr. D. S. Brown. He had begun by seeking for a light motive power, and his proposal for a steam-engine with an India rubber bag instead of a cylinder has already been noticed; but becoming aware of the enormous importance of stable equilibrium, he turned his attention in that direction. He exhibited at the meeting of the Aeronautical Society of Great Britain, in 1873 a model consisting of two planes of equal size, one placed before the other at some distance and connected by a rod, which arrangement showed much greater stability than a single plane, and he followed this up at the next meeting, in 1874, by exhibiting models of what he called his aero-bi-plane, which showed still further improvement in the stability, in consequence of "constructing the anterior edges or frames of the planes rigid, and the other parts yielding or elastic." The two planes might be rectangular and have their anterior edges straight, or these might be curved to diminish the air resistance, and the surfaces were placed one behind the other in the same general plane, so that they did not, as in the case of Pénaud's "planophore," make a slight horizontal angle with each other.
Mr. Brown stated that "the aeroplane should not be inclined to its path of motion, but its surface should form a direct line with it.... the plane being kept at the same elevation by slightly directing its course upward, sufficient to compensate for any fall which may take place." As however, there was in the model a horizontal rudder, which regulated the angle of incidence in flight, Mr. Moy pointed out that the claim was a distinction without a difference. In one model the planes were connected with each other through double rods, so as to admit of a load, representing a car, being placed between them, and Mr. Brown stated that in this form it might be termed a progressive parachute, which was only supported by the air when in forward motion. When this motion was stopped--and this might be done by bringing it suddenly into a large angle with the horizon, so as to increase the resisting surface--the model settled down to the floor. It being, therefore, necessary that the apparatus should start with an initial motion, this was given by an India rubber rope fastened at one end to a post, and at the other, by means of a ring, to a vertical bolt inserted in the under part of the bi-plane, so that it might be released when the rope slackened. The experiments are described in the report of the meeting as follows:
Mr. Brown launched several planes of different dimensions. All showed perfect stability, and, save one or two, floated in the air in a horizontal position across the room, a distance of between 20 and 30 ft., and, apparently, in some instances could have gone further without falling had not the walls intervened. One he suddenly pressed downward in a perpendicular direction by striking it with a stick when in the air; this caused it to dart forward with great velocity in a horizontal course. Mr. Brown considered this an illustration of true flight, as the planes were only inclined the moment he struck the connecting-rod. During the flight they recovered their horizontal position and offered no resistance to the air.
It may be noticed that this arrangement of surfaces, which Mr. Brown referred to as "first steps to flight." differs from that of M. Pénaud in making the rear plane of the same size as that of the front, and parallel therewith, the automatic stability being obtained through the flexibility of the posterior edge. which acts much in the same way as the upward inclination of the rear plane or rudder in Pénaud's apparatus. Whether either of these arrangements, thus slightly differing in construction, will prove adequate in practical operation upon a large scale, can only be ascertained by experiment, but it may be stated that the British aviators have not accepted Mr. Brown's proposal as a solution of the problem of equilibrium, and that some of them believe that he made a mistake in placing his planes parallel with each other; "no change of action taking place whether the planes move from the horizontal to 45° or to any other angle."
The next apparatus to be noticed will be found described in most of the articles on flight in magazines and in encyclopedias but the writer of these lines has been fortunate enough to obtain from Mr. Moy himself still further particulars concerning an experiment which has well been characterized in the reports of the Aeronautical Society of Great Britain as "one of the most determined attempts at solving the problem which has yet taken place."
Fig. 55 shows a front view, from a photograph, of "Thomas Moy's aerial steamer," which was tried in the open air at the Crystal Palace near London in June, 1875. The supporting surfaces consisted in two aeroplanes, one in front and the other behind the propelling aerial wheels; the planes being of linen, stretched upon bamboo canes, and set at an angle of 10 with the horizon, the rear plane being placed higher than the front plane, but parallel therewith. A third steering plane, of smaller size, governed by a horizontal wind wheel with screw vanes, was placed in the rear to serve as a horizontal rudder. The front plane measured 50 sq. ft., and the after plane had 64 sq. It. of surface; their true size in relation to the whole apparatus being inadequately shown in the figure, because of the perspective, as they are seen nearly edgewise.
FIG. 55. -- MOY -- 1875.
Between the two supporting aeroplanes were placed two propelling aerial wheels 6 ft. in diameter, each provided with six blades. These were first made of thin laths to approximate to true helices, but were afterward made of Scotch cambric. The blades or vanes were by a most ingenious and simple arrangement caused to change their angle of incidence as they rotated, so as to be "successively caused to be inclined to the line of onward motion of the machine, in such a manner that the blades on one side of the neutral line will be caused to act downward on the air with both a raising and propelling effect, while those on the other side thereof will, in their upward course, be impinged upon by the air with only a lifting tendency." This being in effect an aerial screw in which the pitch was variable in every portion of the revolution, and constituting the chief feature of novelty in the whole apparatus.
The steam-engine was placed between the two aerial wheels, and was a marvel of lightness. The diameter of the cylinder was 2 1/8 in. and the stroke 3 in., with 520 to 550 revolutions per minute. The heating surface was 8 sq. ft. or 2 2/3 sq. ft. per horse-power, the boiler being of the water-tube description, and the steam pressure was 120 to 160 lbs. per square inch, the fuel being liquid and burned in Russian lamps. The engine weighed, with the boiler, 80 lbs and developed fully 3 H.P., being at the rate of 26 2/3 lbs. per horse-power. or about the same as the 1868 engine of Mr. Stringfellow as rated by himself. Mr. Shill a clever mechanician who exhibited a remarkably light engine in 1868 was associated with Mr. Moy in producing the 1875 engine, and had an interest in the patents, so that the apparatus was also known as the "Moy & Shill aerial steamer." It was 14 ft. long and about 14 ft. wide, was mounted on three wheels, and weighed 216 lbs., thus being proportioned at the rate of 0.53 sq. ft. of sustaining surface per pound of weight, omitting the lifting effect of the aerial wheels, which measured 60 sq. ft. more.
The inventor estimated that at a speed of 35 miles per hour the apparatus would be able to rise from the ground and glide upon the air, and this estimate seems fully confirmed by Professor Langley's recent experiments, which show that the uplift on a plane surface of 114 sq. It. at an angle of 10 would be fully 206 lbs., while somewhat higher results are obtained from the table of "lift" and "drift" heretofore given herein, when taken. in connection with Smeaton's table of wind pressures.
After some preliminary tests a path around one of the fountains at the Crystal Palace was selected, which had a diameter of nearly 300 ft.; a pole was erected at the center of the fountain, and two cords were run from the top of the pole to each end of the machine in order to keep it at a uniform distance from the center. The gravel had been rolled, and steam was got up. The gravel, however, proved too rough, it shook the steamer and largely increased the traction. Then a board walk was laid over the path, and again steam was got up and a good run was made around the fountain, the machine (which was only a large model and could not carry an engineer) being wholly propelled by the action of the aerial wheels upon the air, acting only as driven.
The utmost speed attained was 12 miles per hour, while 35 miles an hour was required to cause it to leave the ground. This indicated that the resistances had been underestimated, which resistances consisted in the traction upon the boards, the air resistance on the framing, cordage and ground wheels, and also in the "drift" due to the inclination of the sustaining planes. With our present knowledge we can say that at a speed of 35 miles per hour (6 lbs. per sq. ft.) the latter would have been: 114 X 6 X 0.0585 = 40 lbs., and as the speed would have been 3,080 ft. per minute, the power required by the "drift" was: (40 x 3080)/33.000 = 3.73 H.P., to say nothing of the other elements of resistance, so that it is not strange that only 12 miles an hour was attained.
Mr. Moy needlessly handicapped himself in starting from the ground by a level run. He reasoned, like many others before and since, that "when they were coming down power was wanted, and, of course power was especially wanted when they were going up," but he encountered thereby, in an experimental machine, all the additional resistance of the traction upon the boards. He considered the propriety of launching the apparatus from a height, or down an incline, but then this costly machine, built wholly at his own expense, would surely have come to grief, for he says that "the transverse stability was better than the longitudinal stability, but both were bad," and unless this was first remedied, it really was not safe to experiment.
Mr. Moy also placed his sustaining aeroplanes at too obtuse an angle, for if he had simply doubled their area, and inclined them at 5° instead of 10° the "lift" would have been, by the table, at 35 miles per hour: 228 X 6 X 0.173 = 236 lbs., or practically the same as before, but the "drift" would have been diminished to: 228 X 6 X 0.0152 = 20.79 lbs., or about one half of that heretofore calculated.
Such experiments would doubtless have been tried had ample means been forthcoming, but other things were more pressing, for it was recognized that some modifications would be required in the steam generator, which was provided with six Russian lamps burning methylated spirits, and it was found that when running in the open air, the fumes from the three forward lamps extinguished the three after lamps, and thus reduced the power one half. Before even this difficulty could be remedied the machine was seriously injured by the wrecking of the bamboo aeroplane frames, while it was being moved stern' first across the grounds, in a fierce gale, and Mr. Moy then decided to rearrange it for experiment, as to its vertical lifting power, by substituting 12-ft. aerial wheels with vertical axles tried under cover.
The total surface of these new aerial wheels was 160 sq. ft., and the weight, including engine, boiler and all accessories was 186 lbs. It was found that by counter-balancing 66 lbs. with levers, the wheels would lift the remaining 20 lbs., thus showing a lift of 40 lbs. per H.P., or about he same as the best performance which has been attained with other forms of screws.
Mr. Moy, as the result of his various experiments, then proposed to build a much larger apparatus, with an engine of 100 H.P., and capable of carrying several men, both to avail of the diminished relative weight and resistance of larger engines and to secure intelligent control while in action; but the money could not be secured for this purpose. It would necessarily have cost a large sum, and at that time (1875) not only was the whole subject of aerial navigation generally considered as visionary, but there was not sufficient knowledge to enable the public, or even scientific men, to distinguish the difference between a wild proposal sure to fail to compass flight, and a promising experiment which was worth following up--a condition of affairs which has in a measure continued to this day, and which this account of "Progress in Flying Machines" is partly written to remedy.
So Mr. Moy got no money, but he had instead "two chancery suits about shares in his patents, with no help from any one;" his experiments had brought him down in funds, and he had to turn to hard work to live. As he justly remarks, "Unless you can lift the last ounce of a model, the unscientific people call it a failure, and few can appreciate that as size and weight increase, the relative hull resistance decreases, by reason of its diminished surface in proportion to its cubic contents." He, however , continued to take an active interest in the subject; read papers at the meetings of the Aeronautical Society of Great Britain, made private experiments with planes, both in air and in water, as well as with methods for securing automatic stability, and with an improved method of propulsion
In 1879 Mr. Moy exhibited at the meeting of the Aeronautical Society the small flying model shown in fig. 56, which he described as a "military kite" mounted upon wheels and provided with propelling gear. The front plane measured 660 sq. in. of surface, and the after plane, of half its linear dimensions, measured 165 sq. in. They were made of cambric, fastened to a central box-girder of thin pine, running lengthways, and mounted on small wheels, the aeroplanes being given a diedral angle, as shown, and the angle of incidence fore and aft being adjustable. At each end of the central stick or box-girder cross-arms were fastened, which held in position strands of indict-rubber strings, one on each side of the central stick and parallel therewith, the untwisting of which rotated (in opposite directions) two screw propellers with two vanes each. These propellers are removed in the plan and side view of fig. 56, for the sake of clearness, but are shown in the end elevation or front view.
FIG. 56. -- Moy -- 1879.
The model weighed 24 oz., of which 3 1/2 oz. was in the india-rubber springs, and with 500 turns of the rubber it would run on its wheels over a smooth surface, and under favorable circumstances would rise for a short distance upon the air, It would, of course, fly from the hand like Pénaud's planophore, but showed, like it, great waste of power, the supporting surfaces being at the rate of 3.82 sq. ft. per pound, and the angle of incidence required for it to rise from the ground being 8°; and more unfavorable than a flatter angle, at which, however, it would not have possessed sufficient "lift." Mr. Moy says that "its transverse stability was very good, but its longitudinal stability was defective, and was a perfect puzzle at that time, but now all these troubles are overcome."
He has recently patented in England a method for automatically securing horizontal stability, and it is to be hoped that he will be enabled to renew his experiments,
Mr. Moy has also been an observer of soaring or "sailing" flight, and he described the sailing of the albatross in a wind, on rigid wings, in a paper read before the Aeronautical Society in 1869 . Deeming it possible for man to imitate this performance, but recognizing the prodigious difficulty of reproducing the complicated shape and arrangement of curved surfaces (not planes), with which impulse is received from the wind, and of imitating the exquisite balancing through which the soaring birds perform this feat, he read a paper before the "Balloon Society," in 1884 in which he proposed an ingenious method of carrying on the many experiments required, with no greater danger than that of getting wet, by taking a start at sea from a lifeboat on the crest of the waves in a gale, equipped with a pair of wings and an inflated Boynton dress In the hope that some aviator, favorably situated, may try this experiment, the paper, rewritten for the purpose, will be given in the appendix.
Aéronaute, January, 1872. Page 4.
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