A Treatise Upon the Art of Flying, by Mechanical Means, with a Full Explanation of the Natural Principles by which Birds are Enabled to Fly: Likewise Instructions and Plans, for Making a Flying Car with Wings, in which a Man May Sit, And, by Working a Small Lever, Cause Himself to Ascend and Soar Through the Air with the Facility of a Bird...

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J. Simmons, and sold by Longman, Hurst, Rees, & Orme, London, 1810 - 67 pàgines

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Pàgina 7 - There be three things which are too wonderful for me, yea, four which I know not: The way of an eagle in the air; the way of a serpent upon a rock; the way of a ship in the midst of the sea; and the way of a man with a maid.
Pàgina 14 - ... fastened to him, leaving the whole weight of his body unsupported. Friar Bacon, who lived nearly five centuries ago, wrote upon the subject, and he affirms that the art of flying is possible ; and many others have been of opinion that, by means of artificial wings affixed to the arms or legs, a man might fly as well as a bird. The philosophers of the reign of King Charles the Second were much engaged with this art. The famous Bishop Wilkin, who, in 1672, published a treatise upon flying, was...
Pàgina 23 - ... elasticity ; it was expedient too that the quill feathers should separate and open to let the upper air pass through the wings, to facilitate their ascent when they are struck upwards ; it was also necessary that they should all shut close together, forming each wing into a complete surface or web, when they are, by the muscular power of the bird, forced down in order to give a more secure hold upon the air below, and by that means keep the bird up. Now if we do but examine the quill feathers...
Pàgina 36 - ... sufficient to exult in the success of my experiment, which proved to me, in a very satisfactory manner, that what I had conceived to be the cause of the projectile motion of birds was really the cause, and that if I could but give a vertical motion to the wings, so that they might strike upon the air with a sufficient force, they would then increase the reaction of the air, and instead of being projected in an oblique descent, totally overcome their specific gravity, and continue flying in an...
Pàgina 35 - ... as I could, the wings and tail of a bird when expanded in a passive state. I then suspended a small weight from under them, with a piece of thread, exactly in the centre of gravity ; I held them up as high as I could reach, then took away my hand and left them flat upon the air, without giving any impulse to them whatever ; and by the weight pressing downwards the air under the wings became, in some degree, compressed, and by its reaction against the under side and the back edges of the wings,...
Pàgina 40 - ... feet each in length, let them be horizontally expanded, and fastened upon the top edge on each side of the car, with two joints each, so as to admit of a vertical motion to the wings, which motion may be effected by a man sitting and working an upright lever in the middle of the car ; a...
Pàgina 57 - ... similar to what may be observed in the raising of a common paper kite, except in a right angle, or perpendicular line ; but the nearer the angle of ascent inclines to the line of the horizon, the easier will the machine be found to ascend. I believe pigeons can ascend very near in a perpendicular line, but such an ascent would be too incommodious for artificial flying. When...
Pàgina 56 - ... before the car is placed there ; being thus elevated he will have depth enough on each side of the car to admit of his wings striking upon the air. He must then push the lever forward about eighteen inches from its perpendicular line, the tips of the wings will then rise three feet and a half above the level of their joints ; he must then, with a brisk exertion, pull the lever backwards eighteen inches past the perpendicular line, and the tips of the wings will be struck downwards, passing through...
Pàgina 18 - Desmarchais assert that it measures eighteen feet across the wings when expanded ; its beak is so strong as to pierce the body of a cow ; and it is positively asserted that two of them are capable of devouring that animal. They do not even abstain from attacking man himself ; but, fortunately, there are but few of the species.
Pàgina 21 - The great feathers, that were of a beautiful shining black, were two feet four inches long. The thickness of the beak was proportionable to the rest of the body ; the length about four inches ; the point hooked downwards, and white at its extremity ; and the other part was of a jet black.

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