NO. 3 LANGLE\ MEMOIB ox MECHANICAL FLIGHT 259 



the large aerodrome, which had been determined by calculation from the results 

 obtained with the steam-driven models, was correct. For il was assumed thai 

 if the quarter-size model, which was an exact counterpart of the large machine, 

 should fly successfully with the same balancing as thai calculated for the large 

 one, the large one could reasonably be expected to ad similarly. II was at first 

 thought best to make another test with the model immediately after recovering 

 it from the water, but by the time it could be brought into the house-boat and 

 the water which had got into the engine cylinders could he removed and the 

 engine made to work properly quite a strong wind had sprung up and rendered 

 further tests of the model on this day impossible. If the launching track for the 

 small machine could have remained on the top of the boat without interfering 

 with the completion of the preparations for testing the large machine, it would 

 have been left there and other tests made with the model when Ihe weather was 

 suitable, but as this could not he done without interfering with the work on 

 the large machine, and the delays with the model had already been so great, the 

 small track was immediately removed and the model stored away in the house- 

 boat for possible later tests. 



At the first it was impossible to account for the engine on the model run- 

 ning so irregularly and slowing down so soon after it was launched, as it was 

 felt very certain that the cylinders could not in so short a time, and with the 

 aerodrome actually moving through the air, have heated up sufficiently to cause 

 it. After a while, however, one of the workmen volunteered the information 

 that in his zeal to fill the fuel tank completely so as to insure a long flight, 

 he had caused the tank to overflow so that some of the gasoline had run into 

 the intake pipe, and that he had noticed gasoline dripping from the intake pipe 

 as the machine went down the track. This excess gasoline in the intake pipe 

 had caused the mixing valve which controls the quality of the explosive mix- 

 ture to be improperly set, so that it would not furnish the proper mixture when 

 the fuel was supplied in the proper way by the carburetor, and consequently 

 when this excess gasoline had evaporated, the mixture furnished to the engine 

 was not proper, and it consequently slowed down, there being no human intelli- 

 gence on board to correct the adjustment of the mixing valve. 



A series of seven photographs of this flight, of the quarter-size model is 

 given in Plates 87 to 93. Plate 87, taken with a kodak from the tug-boat sta- 

 tioned several hundred yards directly ahead of the house-boat, shows the ma- 

 chine in full flight heading directly for the tug-boat. Although the aerodrome 

 was about fifteen or twenty feet higher above the level of the water than the 

 camera, still, at the considerable distance from which the photograph was taken, 

 this view would not show so much of the under side unless the machine had 

 been pointing upward. The photograph also proves very (dearly that at the 

 time it was taken the machine had certainly not dropped at all below the level 



