262 SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE VOL. 27 



hide and azimuth, which these cameras automatically recorded, the speed, height, 

 etc., of the machine in flight could be accurately computed. After stationing 

 the tug-boats at proper points, so as to render assistance should the aerodrome 

 come down into the water at a considerable distance from the house-boat, it was 

 found, upon attempting to start the engine, thai for some reason il would not 

 operate. The sparking battery which had been placed at the extreme rear of 

 the aerodrome was found to be giving such a weak spark that it would not 

 ignite the mixture in the cylinders. Upon removing the connection which 

 grounded the terminal of the battery to the framework and replacing it by a 

 large copper wire leading up to the engine so as to decrease the resistance of 

 the circuit it was found that the battery still would not give sufficient spark. 

 A large quantity of dry cells, such as were used for the engine, had been pro- 

 cured to insure against delay from lack of batteries, but upon attempting to 

 gei a new set from this reserve supply it was found that they, as well as the set 

 that was on the machine, had so deteriorated that instead of giving eighteen 

 amperes on short circuit they would give only three, which was not a sufficient 

 current to enable the engine to operate. No shop tests on the huge engine had 

 been made since the large aerodrome had been brought down the river, as no 

 provision had been made for properly supporting the aerodrome in the house- 

 boat in such a way as to permit the large propellers to whirl around without cans 

 ing damage, and, therefore, the batteries which had hitherto proved to be suitable 

 had not had any special test since they had been brought down the river. As no 

 batteries suitable for use were on hand, and as none could be procured from a 

 point nearer than Washington, the test had to be abandoned for the day and 

 the aerodrome removed to the interior of the boat. 



Il was at first impossible to account for the rapid deterioration of so large 

 a number of dry cells, but it was later found that the damp, penetrating fogs 

 which had been experienced for nearly two months were responsible for it, and 

 that in order to preserve the batteries in such a climate it was necessary to 

 place them in metallic boxes which could be nearly, if not quite, hermetically 

 sealed. New batteries were immediately procured from Washington, and before 

 again mounting the aerodrome on the Launching track provision was made for 

 testing the engine inside the house-boat. 



Up to this time the wings had been stored inside the house-boat by sus- 

 pending them from the ceiling, but the time required to hoist them to the 

 upper works on top of the boat, after the main body of the aerodrome had 

 been placed on the launching car preparatory to making a flight, had added so 

 greatly to the delay, and consequently to the difficulty of getting the machine 

 entirely ready for a flight while the weather conditions remained suitable for 

 a test, that it was decided to build some framework on the upper works and 

 cover il wilh canvas so as to provide some boxes in which the wings could be 



