3 3 Two cross bars three feet each, holding the two side rails together.-4 The middle rib with its two ends fastened to the side rails, bending down in the middle, so as to form the bottom of the car three feet below the top rails.-5 5 The two fore ribs to be united to the fore ends of the side rails, and to bend down to the middle rib, at the bottom of the car, and there joined to the back rib, which must have its upper end well fixed to the hindermost cross bar.-6 The seat for the man to sit upon, fixed with its front ten inches behind the axis of the crank.-77 Two foot-boards for the man's feet to rest upon.-8 The crank, two feet six inches long. 9 The head of the crank, eighteen inches long.-10 The axis of the crank, eighteen inches long.-11, 12 Two iron rods, fixed with joints to the two inner ends of the wings, and then to the two ends of the crank head.-13, 13 Two shafts to give expansion to the tail.-14 Small cords to brace the fore shaft of the wings.-15 Eight longitudinal parallel cords, well stretched, to which slips of silk must be sewed, each slip about seven inches broad; and the oblique cords, 16, must be well stretched and knotted to them at each part where they cross.-17 A number of small threads, running across the under side of the wings at about four inches asunder, to which each slip of silk must be attached, that they may be prevented from opening more than half an inch from each other when the wings move upwards. No. 3. A pair of paper wings, ten inches each in length, with a tail ten inches long down the middle; the frame or skeleton of the wings and tail to be formed of small sticks, about the thickness of a crow quill, and the paper must be fixed on by its edges being neatly pasted to the sticks: at the posterior angle of the wings the paper must have a piece of fine thin cloth pasted upon it to give strength to it at the corner. No. 4. Represents a pigeon flying from the ground in the angle of sixty. No. 5. Represents a grebe flying horizontally. TO THE Right Hon. Earl STANHOPE. MY LORD, AS far as an obscure individual like myself can judge of exalted characters, I am induced, in unison with public opinion, to hold a belief that your lordship is possessed, in a very superior degree, both of genius and a knowledge of the sciences; as well as a known predilection for every thing that is calculated to improve and extend the mechanic arts, or to meliorate the condition of mankind. To acknowledge also that your lordship is equally pre-eminent in the senate, is but paying a tribute which is very justly due to your patriotism, and the great exertions which you have made in advocating the cause of humanity. Every friend to his country must hold in grateful remembrance, the energetic and manly opposition which your lordship evinced to prevent the commencement of a war more undefined in its object, more inefficient, and more direful and ruinous in its consequences to our country, than any war it was ever madly and unjustly plunged into. My countrymen have now great cause also to remember, with indignation and deep regret, that, in return for your opposition to the origin of those baneful effects, which your lordship clearly foretold, and are now but too severely felt; in return for your wise counsels, and patriotic zeal, your lordship met with every coarse insult and contumely, which blind folly and malice could suggest. But your lordship has this inestimable consolation, that your life has been most honourably engaged ;—not with the savage arts of murder; not with the burning of towns, and the destruction of their unoffending and defenceless inhabitants; not with the filling of Europe with miserable widows and orphans; not with the ruin of manufactures and commerce, and the violation of the sacred constitutional rights and liberties of your countrymen; not with the low, base, and contemptible arts of any corrupt and venal faction; not with the arts of tyranny and oppression, or force and fraud; not with the machiavelian arts; but with the noble arts which are conducive to peace, civilization, and the convenience and happiness of mankind. Had I invented a diabolical engine that would effectually have swept off from the earth a considerable portion of its unwary inhabitants, I should never have thought of addressing your lordship; I must have sought patronage from another quarter; but considering the subject of this work, I thought no one was more able than your lordship to form a just estimation of its merits. I have, therefore, taken the liberty of dedicating it to you; flattering myself that the theory it contains, will be honoured with your lordship's approbation, which will greatly contribute to the pleasure of, My Lord, Your Lordship's humble Servant, HULL, Feb. 1810. PREFACE. I AM laying before the public a treatise upon a subject, perhaps, as extraordinary in its nature as any thing that has lately come before them; and after a candid perusal, should it meet with approbation from the friends to arts and sciences, my utmost pride will be gratified. The flight of birds, although so common and familiar to our sight, is certainly as great a phænomenon as any in the creation; and artificial flying, when accomplished, may be considered as one of the greatest wonders of the mechanic arts; which I firmly believe attainable upon the plan I have suggested. In this little work, I have shewn that birds wings do not increase their expansion in exact ratio with the increased specific gravity of their bodies; I have given a demonstration of the cause of the projectile motion of birds, the discovery of a true knowledge of which has bid defiance to philosophers in all ages; which, with other discoveries, I trust will prove that I have given consistency to what henceforth may be denominated the science of flying, and, which may alone be deemed of considerable importance to science, had nothing more than that been brought forward; but as I have gone much further, and have advanced arguments, and given plans to render the art of flying practicable, the importance of this little treatise becomes obvious, more particularly so if we take into consideration the various purposes to which artificial flying may be applied. When my work was just ready for the press, I was much surprised at the account a friend gave me of what he had seen that day upon flying, in a monthly journal. I immediately procured a sight of it, and found it to be an ingenious paper, written by Sir George Cayley; and I own I was astonished at the perusal. I conceived it to be very extraordinary that two persons, not having the least knowledge of each other, should be publishing their thoughts at the same time, upon such a subject; nor was I less surprised to find the subject treated of there, in a manner so rational, and far superior to any thing I had ever seen before. From what Sir George has thought, and the calculations he has made upon the subject, he is so san |