THE CONQUEST OF TIME AND SPACE 



twice the power could have been obtained. But steam 

 was considered too dangerous, and some other motive 

 power which combined lightness with power seemed 

 absolutely essential. The electric motor gave promise 

 of success in this direction, and in 1883 the two Tis- 

 gandier brothers in France applied such a motor to a 

 balloon that was able to make headway against a seven- 

 mile breeze, but was still far from fulfilling the require- 

 ments of an entirely dirigible balloon. Two years later 

 the motor-driven balloon La France, of Renard and 

 Krebs, attained a speed of fourteen miles an hour, and 

 showed a distinct advance over all preceding models. 



Meanwhile motors were being reduced in weight and 

 increased in power, and the hearts of aviators and 

 balloonists were cheered by the fact that the light metal, 

 aluminum, was steadily growing cheaper. Visions of 

 an all-aluminum balloon were constantly before the 

 minds of the inventors, and in 1894 such dreams took 

 practical form in a balloon whose construction was 

 begun by Herr Schwartz, under the auspices of the 

 German Government. This balloon was of most com- 

 plicated construction, depending for its lifting power 

 upon the gas-filled aluminum tank, but utilizing for its 

 steering-gear many of the features of the aeroplane. 

 It was essentially a balloon, not a flying- machine, how- 

 ever, with a ten to twelve horse-power benzine-engine 

 actuating iour propelling screws. 



Before the balloon was completed Herr Schwartz 

 died, but his plans were known to his wife, and, although 

 considerably altered, were carried to completion. When 

 all was finished, Herr Jaegels, an engineer who had had 



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