THE PROGRESS OF SCIENCE 



409 



THE PEOGRESS OF SCIENCE 



LANGLEY MEMOIR ON MECHAN- 

 ICAL FLIGHT 



In the development of mechanical 

 flight the United States has taken an 

 honorable place both in theory and in 

 practise. The work of Langley, Cha- 

 nute and the Wright brothers can not 

 be paralleled by any other nation. 

 While in many directions we have done 

 more than our share in mechanical in- 

 vention, it has often happened that we 

 have depended on Great Britain, 

 France and Germany for scientific 

 principles. But Langley was an emi- 

 nent physicist and Chanute a leading 

 engineer. It is interesting to know 

 how far their achievements in aero- 

 nautics were based on mathematics and 

 physical research and how far on em- 

 pirical trials. The Langley "Memoir 

 on Mechanical Flight," just published 



by the Smithsonian Institution, gives 

 full details in regard to the work done 

 by Langley and under his direction. 

 The first part of the volume was in the 

 main written by him in 1897; the 

 second part, dealing with ■ further ex- 

 periments with the small models and 

 with the large aerodrome, has been 

 written by Mr. Charles M. Manly, who 

 became assistant in charge of the ex- 

 periments in 1898. 



In 1891 Langley announced as the 

 result of experiments carried on 

 through previous years that machines 

 could be constructed which would give 

 such a velocity to inclined surfaces 

 that bodies indefinitely heavier than 

 the air could be sustained upon it and 

 moved through it at a great speed. 

 As a result of experiment and theory 

 it was proved that one-horse power 





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Path op Aerodrome Flights, May 6 and November 28, 1896, 

 near quantico, va., on the potomac river. 

 VOL. LXXIX. — 28. 



