ON AERIAL LOCOMOTION. 317 



The wiugs of all Hying creatures, whether of birds, bats, butterflies, 

 or other insects, have this one peculiarity of structure in common : The 

 front, or leading- edge, is rendered rigid by bone, cartilage, or a thicken- 

 ing of the membrane ; and in most birds of perfect flight even the indi- 

 vidual feathers are formed upon the same condition. In consequence 

 of this, when the wing is waved in the air, it gives a persistent force in 

 one direction, caused by tlie elastic re-action of tlie following portion of 

 the edge. The tins and tails of fishes act upon the same principle: in 

 the most rapid swimmers these organs are termed " lobated and 

 pointed." The tail extends out very wide transversely to the body, so 

 that a powerful impulse is obtained against a wide stratum of water, 

 on the condition before explained. This action is imitated in Macin- 

 tosh's screw-propeller, the blade of which is made of thin steel, so as to 

 be elastic. While the vessel is stationary, the blades are in a line with 

 the keel, but during rotation they bend on one side more or less,accord- 



" These buoyant sails, possessiDg iimueuse power, will, as we have before remarked, 

 serve as tloatiug observatories. - - - Elevated iu the air, a single seutiuel, 

 with a perspective, could watch and report the advance of the most powerful forces, 

 while yet at a great distance. He could mark their line of march, the composition 

 of their force, and their general strength, long before he could be seen by the enemy." 

 Again, at page 53, we have an account of ascents actually made as follows: " Nor 

 was less progress nsade in the experimental department, when lai'ge weights were re- 

 quired to be raised or ti'ansposed. While ou this subject, we must not omit to observe 

 that the first person who soared aloft iu the air by this invention was a lady, whose 

 courage would not be denied this test of its strength. An arm-chair was brought ou 

 the ground, then lowering the cordage of the kite by slackening the lower brace, the 

 chair was firmly lashed to the maiu line, and the lady took her seat. The main-brace 

 being hauled taut, the huge buoyant sail rose aloft with its fair burden, continuing 

 to ascend to the height of 100 yards. Ou descending, she expressed herself much 

 pleased with the even motion of the kite, and the delightful prospect she had enjoyed. 

 Soon after this, another cxperimeut of a similar nature took place, when the invent- 

 or's son successfully carried out a design not less safe than bold — that of scaling, by 

 this powerful .'lerial machine, the biow of a cliff 200 feet in perpendicular height. 

 Hero, after safely landing, he again took his seat in a chair expressly prepared for 

 the j)urpose, and, detaching the swivel-line, which kept it at its elevation, glided 

 gently dowu the cordage to the hand of the director. The buoyant sail employed on 

 this occasion was 30 feet iu height, with a proportionate spread of canvas. The I'ise 

 of the machine was most majestic, and nothing could snqiass the steadiness with 

 which it was maneuvered, the certainty with which it answered the action of the 

 braces, and the ease with which its power was lessened or increased. - - - Sub 

 sequeutly to this, an experiment of a very bold and novel character was made upon 

 an extensive down, where a wagon with a considerable load was drawn along, whilst 

 this huge machine, at the same time, carried an observer aloft iu the air, realizing 

 almost the romance of flying." 



It may be remarked that the brace-lines here referred to were convoyed dowu the 

 main-line and managed below ; but it is evident that the same lines could be managed 

 with e<iual facility by the jjcrsou seated iu the car above; and if the main line were 

 attached to a wati;r-drag instead of a wlieeled car, the adventurer could cross rivers, 

 lakes, or bays, with considerable latitude for steering and selecting tlui point of 

 landing, by hauling on the port or starhoaid brace-lines as required. And from the 

 uniformity of the lesistance otlered by the water drag, this experiment c(juld not bo 

 attended witii any greater amount of risk than aland flight by the same means. 



