TRIBUTE. — SAMUEL PIERPONT LANGLEY 

 PIONEER IN PRACTICAL AVIATION. 1 



By Henky Leffmann, Member of the Franklin Institute. 



[With 9 plates.] 



It may be safely assumed, I think, that mankind from its earliest 

 period of self-consciousness had aspirations of flying. In primitive 

 times birds were more abundant and varied than at present, at least 

 in civilized countries, and the ease and grace of their flight must have 

 profoundly impressed the rudest races. The legend of Icarus and his 

 waxen wings is one of the expressions of this feeling. Among the 

 world-wide and very ancient witchcraft legends we find the gift of 

 flying a usual feature. In the later phases of these superstitions, 

 especially as they appear in English-speaking nations, the highly un- 

 romantic method of broomstick flight is eminently characteristic. 



Notwithstanding all aspirations, no practical method of flight by 

 human beings can be demonstrated until 1783, when the brothers 

 Montgolfier sent up a hot-air balloon. Hydrogen gas was soon after 

 substituted for air, and the balloon in substantially its present form 

 was produced. The standard form of balloon, however, does not fly 

 in the full sense of the word ; it simply floats in the air, subject to the 

 currents thereof. Its modification, the dirigible, which has acquired 

 such prominence in recent years, especially in the form known as the 

 Zeppelin, has solved some of the problems of flight, but it is an ex- 

 pensive, complicated, and untrustworthy form, and has very limited 

 practical application. 



All creatures that fly are heavier than air, and this leads to the 

 view that it will be by the method they use — namely, reaction upon 

 the air as a material substance — that true flight will be obtained. 



This was Langley's view, and it is to his honor that he insisted on 

 this principle, and pointed the way, both in theory and practice, to its 

 accomplishment. It is the purpose of this paper to summarize his 

 main work, and to present his claims to the gratitude and admiration 

 of the American people. The history of the later years of his life, 



1 Presented at a meeting of the Alumni Association of the Franklin Institute, held 

 Thursday, Oct. 31, 1918. Reprinted by permission from the Journal of the Franklin 

 Institute, vol. 187, No. 1, January, 1919. 



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