The great advantage of the aeroplane over any other mode of flying is thus described by Major Baden-Powell, one of our greatest living authorities on aeronautical matters: “When people realise that in the case of the aeroplane a contrivance like the awning of a small steam launch is capable of supporting the man and the engines, and that in the case of the balloon a mass like a big ship is necessary to lift the same weight, one can readily understand the advantages of the aeroplane, especially when to the drawbacks of the bulky balloon are added the great difficulties inherent in the retention of a large volume of expensive, inflammable, and subtle gas, ever varying in its density.”
The most successful inventors of flying machines at the present day are all Americans, though one of them has made his experiments on this side of the Atlantic. They are Sir Hiram Maxim, inventor of the famous gun, and one of the greatest mechanicians living; Professor Langley, Secretary of the Smithsonian Institute, Washington; and the brothers Wright.
Mr. Maxim, as he then was, commenced his experiments in the early nineties. As we have already shown, he went to Nature for his guide, and in constructing his flying machine took as his analogy the flight of birds. Birds urge their way onwards in the air by reason of the strength of their wings. A flying machine must do the same by the power of its engine; and as a bird’s wings must be strong in proportion to the bird’s weight, so the strength or horse-power of the engine must stand in a certain proportion to the number of pounds it weighs. Mr. Maxim’s first task, therefore, was to discover what proportion this must be, and by his experiments he arrived at a conclusion which Professor Langley in America, working at the same task at the same time, but quite independently, had also proved to be true, namely, that the faster a machine travels through the air the greater weight it may carry; or, in other words, the quicker a body moves through the atmosphere the less tendency will it have to fall to the ground. A quick-flying bird like an albatross, therefore, flies with less exertion, and so could carry a greater weight, than a slow-moving bird like a goose. It must therefore be to the advantage of the flying machine that its engines should attain as great a speed as possible.
Maxim’s next task was to construct a suitable engine. Light but powerful engines had not then reached the pitch of perfection they have now, and his results proved at the time a perfect revelation of what could be done in this direction, and led to great advances being made.
The Maxim Airship.
Next came the designing of the great machine itself. It was an enormous apparatus, weighing over three tons, capable of carrying three men, and supported by no less than 4000 square feet of aeroplanes, placed one above the other. Its steam-engine was of 363 horse-power, and worked two screws of nearly 18 feet in diameter. Before such a machine could rise from the ground it must first have attained a very great forward impetus, and this it was to receive by running at a great speed on wheels along a railway track specially laid down for it. To prevent the apparatus rising unduly, a reversed rail was erected a short distance above, on which the machine would begin to run as soon as it lifted itself off the lower track. Along this railway the flying machine was tested, and it was found that as soon as a speed of thirty-six miles an hour was reached the wheels were lifted clear off the ground, and were running only upon the upper rail. On the last occasion a speed of forty-two miles an hour was attained, when the lifting power became so great that the restraining rail broke away altogether, and the great flying machine actually floated in the air for a few moments, “giving those on board the sensation of being in a boat,” until, steam being shut off, it fell to the ground and was broken.
The enormous expense of his experiments has not prevented Sir Hiram Maxim from repeating them, and he hopes soon to have a much improved machine. Nevertheless his experience and calculations have been of great value to those who would follow in his footsteps, and have proved the possibility of constructing a flying machine which shall fly by virtue of its own motion.
Meanwhile in America Professor Langley was experimenting, independently, almost on the same lines. He also was bent on producing a flying machine, but instead of starting to work upon a large apparatus like Maxim, he began by making models, and gradually worked his way up to bigger things. For many months he studied to understand the principle of those ingenious little toys sometimes seen, which, by means of the tension of a twisted india-rubber band, will keep afloat in the air for a few seconds. Next he constructed small models driven by steam, in which he found his great difficulty was in keeping down the weight. For years he persevered in his work without any great success, until in 1896 he produced a model machine which he called an “aerodrome.” It was quite small, weighing with its engine only 25 lbs., and measuring but 14 feet from tip to tip of its aeroplanes. The experiments were made over water, and the necessary momentum was given by dropping it from a platform 20 feet high. On more than one occasion this little flying machine rose with great steadiness in the face of the wind to a height of 100 feet, moving so smoothly that it might have carried a glass of water without spilling a drop; and then, the steam of its engine being exhausted, sank down gracefully upon the water, having flown about half a mile in a minute and a half. This success encouraged Professor Langley next to construct a full-sized flying machine on the same lines; but this on its first voyage plunged headlong into the water and was hopelessly damaged. The United States Government have since granted him a sum of money to continue his experiments.
Latest of all the airship inventors, and perhaps so far the most successful, are the brothers Wright. Up to the date of writing this the full details of their work are not yet made public, but it is known that on the 17th of December 1903, their machine, which consists of two large aeroplanes driven forward by an engine of sixteen horse-power, after being started along a short track on level ground, rose into the air and flew for about half a mile.