864 



Popular Science Monthly 



The motorcycle mounted on a platform at the side of the 

 airplane. The cyclist is a passenger. Army and navy officials 

 believe it will increase the scouting efficiency of the fliers 



Some Lessons Learned 

 by the Deep-Sea Divers 



EXPERIMENTS made by 

 the British Admiralty 

 and the United States Navy 

 prove that deep-sea diving is 

 feasible. It has been found 

 that the shorter the time a 

 diver takes in getting to the 

 bottom the better, because 

 the body absorbs less nitrogen. 

 Also, the diver must have at 

 least one and one half cubic 

 feet of air per minute at all 

 depths. Lacing the legs of 

 the diver's suit increases his 

 stability and permits him to 

 come to an erect position with 

 ease. It also lessens the dan- 

 ger of his falling or being sud- 

 denly blown to the surface. 



Adding the Motorcycle to the Usual 

 Airplane Equipment 



A MOTORCYCLE was recently carried 

 on a cross-country flight over Ingle- 

 wood and Los Angeles, California, in a 

 fifty-horsepower tractor biplane, on a plat- 

 form between the planes and alongside the 

 fusilage. A motorcyclist was also carried 

 as a passenger. Despite this extra weight, 

 the great plane got off the ground with a run 

 of two hundred and seventy feet and 

 climbed to an altitude of two thousand feet 

 and later to six thousand feet, 

 without any apparent addition- 

 al effort. 



When the flight was fin 

 ished members of the army 

 and navy flying corps 

 were unanimous in their 

 belief that the combina- 

 tion of airplane and 

 motorcycle marks the 

 beginning of a nev.'^ era in 

 military airplane equip- 

 ment. 



In the test flight the mo- 

 torcycle was secured with 

 straps to the airplane in such 

 a way that it could be quickly 

 removed. The platform that 

 held it in position was easily 

 constructed. At one time the 

 airplane landed because it was 

 short of gasoline. This the 

 motorcyclist quickly secured. 



The steel pin fits into a hole 

 in the crank-shaft. When the 

 pin is pulled out, the arm 

 slips loosely on the shaft so 

 that the motion-picture op- 

 erator may go through the 

 motions of taking a picture, 

 to please some one, without 

 exposing a foot of film 



The Fake Camera -Crank for Taking 

 Motion Pictures 



THE life of the camera-man who takes 

 the weekly news motion pictures is not 

 always one of glory. When Mrs. Vander- 

 rich, for instance, asks him to take a 

 picture of her poodle when he wants per- 

 mission to take pictures of her yacht, he 

 finds himself between two fires. Either he 

 must waste some precious film on the dog or 

 he must refuse and be shown the quickest 

 way back. One wise camera-man, how- 

 ever, improvised a fake camera- 

 crank for such occasions. The 

 crank-arm fits loosely on the 

 shaft of the film gear in the 

 camera. When the poodle 

 is going through his antics, 

 the turning arm slips on 

 the shaft, and not a foot 

 of film is exposed although 

 to all appearances a pic- 

 ture is being made. 



On coming to the 

 yacht, however, a flat 

 block on the crank -arm 

 is pressed inward. This 

 pushes a steel pin attached 

 to the thumb block into one 

 of the holes drilled into the 

 crank-shaft. The crank-arm 

 is thereby locked to the 

 shaft, so that when the crank 

 is turned, the film gear op- 

 erates as usual. 



