254 SMITHSONIAN CONTKIBUTIONS TO KNOWLEDGE VOL. '27 



so very brief that the engine could not have been given any attention by the 

 aviator had it needed it, which fortunately it did not. 



It is hardly necessary to recount at any length the great difficulties which 

 were experienced in these tests of the engine in the aerodrome frame before 

 the shafts, hearings, propellers, and, in fact, the frame itself were all properly 

 co-ordinated so that confidence could be felt that all of the parts would stand 

 the strains which were likely to come on them when the aerodrome was in flight. 

 These tests were really not tests of the engine itself, but of the frame, shafts, 

 and bearings. Suffice it to say that nearly a year was consumed by the various 

 breakages of the shafts, bearings, and propellers before it was felt that all of 

 these parts could be depended on, and even then the weakness of the bearings 

 above referred to was fully recognized. Had some of the better-grade balls 

 and steels for the bearings, which have since that time come on the market, 

 been obtainable then, there would have been no difficulty with these bearings. 

 However, this same remark might be made with reference to nearly all of the 

 details of the aerodrome, for it was the accessories, such as bearings for the 

 transmission and propeller shafts, spark plugs, coils, batteries, and a suitable 

 carburetor for the engine, that caused the chief delay after the main difficulty 

 of getting a suitable engine had been overcome. 



