AERIAL LOCOMOTION 435 



machine later, the early depletion of the funds provided by the Board 

 of Ordnance and Fortification made it imperative to utilize what had 

 already been constructed, as it was with the greatest reluctance that 

 Mr. Langley continued the work with the funds of the Institution, and 

 all expense which could be avoided was carefully guarded against. I 

 have thought it well to mention this fact as I have had many inquiries 

 as to why it was that Mr. Langley never realized that the superposed 

 type of construction for the supporting surfaces presented important 

 advantages. 



It was my duty while connected with the Smithsonian Institution to 

 prepare answers to the large number of letters on aeronautical subjects 

 which were constantly received. While some of the writers sought 

 advice, others offered it ; and a large number of the letters indicated 

 that the writers believed that the problem of constructing a successful 

 machine required the discovery of some " secret." In view of this 

 experience, I have thought that it might not be amiss to emphasize, 

 that there is no " secret " which needs to be discovered in order to build 

 a successful machine, but that success is to be achieved by laying out a 

 good design based on a proper knowledge of the laws of aerodromics 

 as at present known, next by giving the greatest care to constructing 

 the parts as strong as possible for the permissible weight, and then 

 trying the machine, not once only, but again and again under condi- 

 tions presenting the least possible danger to the operator. 



In this connection attention may be called to the fact that when a 

 machine is planned and the weight of the different parts is allotted, so 

 that the total weight shall not exceed a certain proportion relative to 

 the supporting area, the experimenter need not be surprised to find, 

 when he has completed his machine that it weighs forty or fifty per 

 cent, more than he has calculated ; for in carrying out the innumerable 

 details of construction small increases in weight at almost every point 

 finally increase the total weight surprisingly. 



In all of the accounts which I have lately seen of the experiments of 

 the Wright brothers, no mention has been made of the fact that the 

 success of the Wrights has been built on the very valuable work of 

 Mr. Chanute, who for many years carried on at his own expense work 

 in the construction and testing of gliding machines, and who I under- 

 stand, not only furnished the Wright brothers with the design for their 

 first gliding machine, but also placed at their disposition his own 

 machines with which they made their initial gliding experiments. 

 There is perhaps no one who has made a closer study and has a more 

 thorough understanding of the whole subject of aerodromics than Mr. 



