240 THE HISTORY OF SCIENCE 



slightly, the engine slowing down. Then it began to 

 rise, moving straight ahead again for three or four 

 hundred feet, the propellers picking up their former 

 rate. Once more the engine slackened, but, before 

 the aeroplane reached the water, seemed to regain 

 its normal speed. For a third time the engine slowed 

 down, and, before it recovered, the aeroplane had 

 touched the water. It had traversed a distance of 

 one thousand feet in twenty-seven seconds. One of 

 the workmen confessed that he had poured into the 

 tank too much gasoline. This had caused an overflow 

 into the intake pipe, which in turn interfered with 

 the action of a valve. 



The larger aeroplane with the engineer Manly on 

 board was first tested on October 7 of the same year, 

 but the front guy post caught in the launching car 

 and the machine plunged into the water a few feet 

 from the house-boat. In spite of this discouraging 

 mishap the engineers and others present felt confi- 

 dence in the aeroplane's power to fly. What would 

 to-day be regarded by an aeronaut as a slight set- 

 back seemed at that moment like a tragic failure. 

 The fifty thousand dollars had been exhausted nearly 

 two years previously ; Professor Langley had made 

 as full use as seemed to him advisable of the resources 

 put at his disposal by the Smithsonian Institution ; 

 the young men of the press, for whom the supposed 

 aberration of a great scientist furnished excellent 

 copy, were virulent in their criticisms. Manly made 

 one more heroic attempt under very unfavorable con- 

 ditions at the close of a winter's day (December 8, 

 1903). Again difficulty occurred with the launching 

 gear, the rear wings and rudder being wrecked be- 



