6o: 



NATURE 



[January 30, 19 13 



THE AJ-IATION EXHIBITS AT THE 

 SCIEXCE MUSEUM, SOUTH KEN- 

 SI XGTON A 



THE aviation exhibition which is open until the end 

 of February at the Science Museum, Soutli Ken- 

 sington, illustrates, in many cases by means of actual 

 flying' machines, the more important scientific prin- 



ciples underlying the practice of flying. Aviation is 

 a new art, and it comes almost as a shock to a visitor 

 to the exhibition to find that so long ago as 1844-5 a 

 model of a flying machine was made by Henson, 

 which, from the illustrations (Figs, i and 2) will be 

 seen to bear a striking resemblance to recent mono- 

 planes. For a moment at least a doubt arises as to 

 the assumed progress of the science in recent years, 

 especiallv when it is realised that one of the greatest 

 difficulties confronting Henson and his cu-|)i(inu. 1, 

 .Stringfellow, was the 

 provision of a powerful 

 and sufliciently light 

 engine. The doubt a^ 

 to our present progress 

 is removed on further 

 inquiry, although we 

 can quite realise that 

 the science of aero- 

 dynamics has, for al 

 least half a century, 

 waited for the develop- 

 ment of the light petrol 

 engine. 



Such differences as 

 occur between Benson's 

 proposed machine and 

 those of the present day 

 are essentially those 

 which have been intro- 

 duced since aeroplanes 

 lifted themselves from 

 the ground and aviators 

 found themselves under the necessity of balancing 

 their machines in more directions than for any pre- 

 viously known form of locomotion. 



The quantitative side of the science of aviation 

 received its beginning and a powerful initial impulse 

 from the work of Langley. As a result of his experi- 

 ments prior to 1S06, Langley calculated the size of 



wings necessary to carry a small steam engine, and 

 made models which flew for considerable distances. 

 Lilienthal afterwards introduced a universally 

 accepted modification into the shape of the wings by 

 giving a camber to the section, but the calculation 

 of the size of the wings necessary to support a given 

 weight at a specified speed still rests substantially on 

 !■"> same data as were obtained by Langley. 



Besides having the 

 proportions of a good 

 lifting surface, the Hen- 

 son model is further in- 

 teresting in that it has 

 a body carefully shaped 

 so as to offer a small air 

 resistance, a point of 

 design now receiving 

 much attention. Such 

 a surface, unless care- 

 fully placed, might, 

 h o W' e V e r, make the 

 machine liable to rolling 

 instability, a point of 

 difficulty which re- 

 mained for nearly two 

 \ears after power-driven 

 aeroplanes capable of 

 carrying an aviator had 

 left the ground. The 

 method of control intro- 

 duced by the Wright 

 brothers, and shown in the exhibition by the 

 actual working of the mechanism of a "Baby" 

 Wright biplane and a skeletonised Wilbur 

 Wright control, made flying for longer periods 

 than a few minutes a regular performance, 

 and has now been universally adopted. Before 

 this stage of progress had been readied, Lilienthal 

 and Pilcher, whose machines are exhibited, lost their 

 lives in an attempt to obtain stabilitv by the motion 

 relative tn the wing surfaces of a ronsidcrnhic nia--~-. 



1 Theillii.trationswhi 

 of the Exhibits, and 'are 

 H.M. Stationery Offio-. 



1 accotiip.iny this article 

 eproduced with pertniss 



XO. 2257, VOL. 90] 



Their experiments were carried out on gliders, i.e. 

 machines which obtained the necessary energy for 

 motion from a descent under the action of gravity, 

 and the aviator's body was the mass moved. This 

 method of control has been entirely superseded by 

 the invention of the Wright brothers. 



How far the modern aeroplane is able to look after 

 its own safety and how far it is dependent on the 

 skill of its pilot is still a subject for investigation 

 The tendency appears to be to trv to obtain stabilitj 



