26 



♦ KNOWLEDGE . 



[Jlly 11, 1884. 



a slight modification, it is probable that Besnier's method 

 would enable an active man to travel over ground with ex- 

 treme rapidity, clearing impediments of considerable height, 

 and taking tolerably wide rivers almost " in his stride " ; 

 but 1 believe that the method could never enable men 

 actually to fly. 



It may be remarked, indeed, that the art of flying, if it 

 is ever attained, will probably be arrived at by means of 

 attempts directed, in the first place, towards rapid passage 

 along tp-r<i Jirma. As the trapeze gymnast avails himself 

 of ihe supporting power of ropes, so the supporting power 

 of the air may be called into action to aid men in tra- 

 versing the ground. The following passage from Tumor's 

 Astra Canlra shows that our velocipedists might soon be 

 outvied by half-flying pedestrians : " Soon after Bacon's 

 time," he tells us, " projects were instituted to train up 

 children from their infancy in the exercise of flying with 

 artificial wings, which seemed to be the favourite plan of 

 the artists and philosophers of that day." If we credit 

 the accounts of some of these experiments, it would seem 

 that considerable progress was made that way. The indi- 

 viduals who used the wings could skim over the surface 

 of the earth with a great deal of ease and celerity. This 

 was accomplished by the combined faculties of running and 

 flying. It is stated that, by an alternate continued motion 

 of the wings against the air, and the feet against the ground, 

 they were enabled to move along with a striding motion, 

 and with incredible speed. 



A gymnast of our own day, Mr. Charles Spencer (" one 

 of the best teachers of gymnastics in this country," says 

 Mr. Brearey), has met with even more maiked success, for 

 he has been able to rai.'-e himself by the action of wings 

 attached to his arms. The material of which these wings 

 were made was too fragile for actual flight; and Mr. 

 Spencer was prevented from making strong efforts because 

 the wickerwork to which the apparatus was attached, 

 fitting tightly round his body, caused pain, and obstructed 

 his movements. Yet lie tells us that, running down a 

 small incline in the open air, and jumping from the ground, 

 he has been able, by the action of the wings, to sustain 

 flight for a distance of 120 feet; and when the apparatus 

 was suspended in the transe|)t of the Crystal Palace (in 

 the spring of 1868), he was able, as we have said, to raise 

 himself, though only to a slight extent, by the action of 

 the wings. It should be remarked, however, that his 

 ap])aratus seems very little adapted for its purpose, since 

 the wings are attached to the arms in such sort that the 

 weak breast-muscles are chiefly called into play. Borelli's 

 main objection applies in full to such a contrivance ; and 

 the wonder is that Mr. Spencer met with even a partial 

 success. One would have expected rather that the jire- 

 diction of a writer in the 7'imes (calling himself Apteryx, 

 or the Windless) would have been fulfilled, and that the 

 "aeronaut, if he flapped at all, wor.ld come to grief, like 

 the sage in ' Rasselas,' and all others who have tried flying 

 with artificial wings." 



The objection founded on the relative weakness of the 

 muscles of man as com[)ared with those of birds (without 

 reference to the question of adaptation), seems at first sight 

 more serious. Although there can be little question that 

 the superior strength of the muscles of birds has been in 

 general enormously exaggerated, yet such a superiority 

 undoubtedly exists to some degree. This gives the bird a 

 clear advantage over man, insomuch that man can never 

 hope by his unaided exertions to rival the bird in its own 

 element. It by no means follows, however, that because 

 man may never be able to rival the flight of the eagle or 

 the condor, of the pigeon or the swallow, he must therefore 

 needs be unable to fly at all. 



It should be remembered, also, that men can avail them- 

 selves of contrivances by which a considerable velocity may 

 be acquired at starting ; and ihut when the aeronaut is 

 once launched with adequate velocity, a comparatively 

 moderate exertion of force may probably enable him to 

 maintain that velocity, or even to increase it. In this case, 

 a moderate exertion of force would also suflice to enable 

 him to rise to a higher level. To show tl.at this is so, we 

 need only return to the illustration drawn from the kite. 

 If a weight be attached to a kite's tail, the kite, which will 

 maint&in a certain height w hen the wind is blowing with a 

 certain degree of force, will rise to a greater height when 

 the force of the wind is but slightly increased. 



Kites afibrd, indeed, the most striking evidence of the 

 elevating power resulting from the swift motion of an in- 

 clined plane through the air, the fact being remembered 

 always that, whatever supporting and elevating power is 

 obtained when air moves horizontally with a certain velo- 

 city against an inclined plane, precisely the same supjiorting 

 and elevating power will be obtained when the inclined 

 plane is drawn or propelled horizontally with equal velocity 

 through still air. Now the following passages from the 

 " History of the Char-volaijt," or kite-carriage, bear signi- 

 ficantly upon the subject we are now upon. The kite 

 employed in the first experiments (made early in the present 

 century) had a surface of fifty-five square feet. "Nor was 

 less progress made in the experimental department when 

 large weights were required to be raised or transposed. 

 While on this subject, we must not omit to observe that 

 the first person who soared aloft in the air by this invention 

 was a lady, whose courage would not be denied this test of 

 its strength. An arm chair was brought on the ground, 

 then, lowering the cordage of the kite by slackening the 

 lower brace, the chair was firmly lashed to the main-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 a hundred yards. On 

 descending, she expressed herself much pleased with the 

 easy motion of the kite and the delightful prospect she had 

 enjoyed. Soon after this another experiment of a similar 

 nature took place, when the inventor's son successfully 

 carried out a design not less safe than bold — that of scaling 

 by this powerful aeiial machine the brow of a cliff two 

 hundred feet in perpendicular height. Here, alter safely 

 landing, he again took his seat in a chair expressly prepared 

 for the purpose, and, detaching the swivel-line which kept 

 it at its elevation, glided gently down the cordage to the 

 hand of the director. The buoyant sail employed on this 

 occasion was thirty feet in height, and had a ]iroportionate 

 spread of canvas. The rise of the machine was most 

 majestic, and nothing could surj ass the steadiness with 

 which it was mameuvred, the certainty with which it 

 answered the action of the braces, and the ease with which 



its power was lessened or increased Subsequently 



to this, an experiment of a very- bold and novel character 

 was made upon an extensive down, where a waggon with a 

 considerable load was drawn along, while this huge machine 

 at the same time carried an observer aloft in the air, reali- 

 sing almost the romance of flying." 



We have here abundant evidence of the supporting and 

 elevating power of the air. This power is, however, in a 

 sense, dormant. It requires to be called into action by 

 suitable contrivances. In the kite, advantage is taken of 

 the motion of the air. In flight, advantage must be taken 

 of motion athwart the air, this motion being, in the first 

 place, communicated while the aeronaut or flying-machine 

 is on the ground. Given a sufficient extent of supporting 

 surface, and an adequate velocity, any holy, however heavy, 

 may be made to rise from the ground ; and there can be no 



