Aerial Locomotion 



1 1 



while the aviator ascends a rope ladder to 

 his seat in the machine. In this way the 

 man would not be exposed to danger dur- 

 ing the critical operation of launching the 

 apparatus into the air, and by a converse 

 process a safe landing could be effected 

 without bringing the machine to the 

 ground. The chance of injury to the ma- 

 chine itself would also be much lessened 

 by relieving it of the weight of the man 

 during the initial process of launching 

 and the final process of bringing the ma- 

 chine down to the ground. 



Such speculations as these of course 

 are only justifiable upon the assumption 

 that it is possible to construct an aerial 

 vehicle large enough and strong enough 

 to support a man and an engine in the air, 

 and yet light enough to be flown as a kite 

 in a moderate breeze with the man and 

 engine and all on board. My experiments 

 in Nova Scotia have demonstrated that 

 this can be done ; and I now therefore 

 find myself seriously engaged in the at- 

 tempt to reduce these ideas to practice by 

 the actual construction of an aerodrome 

 of the kite variety. The progress of ex- 

 periment may be divided into three well- 

 marked stages : the kite stage, the motor- 

 boat stage, and the free flying-machine 

 rising from the water. 



THE KITE STAGE 



In April, 1899, I made my first com- 

 munication on the subject of kites to the 

 National Academy of Sciences in a paper 

 entitled "Kites with Radial Wings," 

 which was reviewed, with illustrations, in 

 the Monthly Weather Revieiv for April, 

 1899 (vol. XXVI, pp. 154-155, plate xi). 

 I made another communication to the 

 National Academy on the 23d of April, 

 1903, upon "The Tetrahedral Principle 

 in Kite Structure," which was published, 

 with ninet)'-one illustrations and an ap- 

 pendix, in the National Geographic 

 Magazine for June, 1903 (vol. xiv, pp. 

 220-251). The substance of the present 

 address was presented in part to the Na- 

 tional Acadeni}' of Sciences at their recent 

 meeting in Boston, Massachusetts, No- 

 vember 21, 1906. The experiments re- 



ferred to, which were undertaken at first 

 for my own pleasure and amusement, 

 have gradually assumed a serious char- 

 acter, from their bearing upon the flying- 

 machine problem. 



The word "kite" unfortunately is sug- 

 gestive to most minds of a toy — just as 

 the telephone at first was thought to be a 

 toy ; so that the word does not at all ade- 

 quately express the nature of the enor- 

 mous flying structures employed in some 

 of my experiments. These structures 

 vi'ere really aerial vehicles rather than 

 kites, for they were capable of lifting men 

 and heavy weights into the air. They 

 were flown after the manner of kites, but 

 their flying cords were stout manila 

 ropes. They could not be held by hand 

 in a heavy breeze, but had to be anchored 

 to the ground by several turns of the 

 ropes around stout cleats, like those em- 

 ployed on steamships and men-of-war. 



One of the great difficulties in making 

 a large structure light enough to be flown 

 as a kite has been pointed out by Pro- 

 fessor Simon Newcomb in an article in 

 McClure's Magazine, published in Sep- 

 tember, 1901, entitled "Is the Air-Ship 

 Coming?" and this difficulty had so much 

 weight with him at that time as to lead 

 him to the general conclusion that — 



"The construction of an aerial vehicle which 

 could carry even a single man from place to 

 place at pleasure requires the discovery of some 

 new metal or some new force." 



This conclusion the Wright brothers, 

 and now Santos Dumont, have demon- 

 strated to be incorrect; but Professor 

 Newcomb's objections undoubtedly have 

 great force, and reveal the cause of fail- 

 ures of attempts to construct large-sized 

 flying-machines upon the basis of smaller 

 models that actually flew. Professor 

 Newcomb shows that where two aerial 

 vehicles are made exactly alike, only dif- 

 fering in the scale of their dimensions, 

 the ratio of weight to supporting surface 

 is greater in the larger one than in the 

 smaller, the weight increasing as the 

 cube of the dimensions, whereas the sup- 

 porting surfaces only increase as the 

 squares. From this the conclusion is 



