MIRACLES OF SCIENCE 



In any event, it seems reasonable to expect that not 

 merely trans-continental but trans-atlantic airship 

 service will be available within a few years. 



Whatever may be the importance of such passenger 

 service, however, it is not this possibility that accounts 

 for the rapid development of the airship. The real 

 spur to inventive ingenuity, accounting for the official 

 interest in the airship so ardently manifested in 

 Germany, France, and England, -has to do with the 

 possibilities of this craft as an agent not of peaceful 

 commerce but of warfare. This accounts for the de- 

 velopnient of the "Society for the Study of Motor 

 Aeronautics" in Germany, and for the recently opened 

 "Deutsch Aero-Dynamic Institute" in Paris. 



The possibility of launching a ton or two of dyna- 

 mite from the safe heights of the upper atmsphere 

 upon the deck of an enemy's ship or within the walls 

 of his fortress, is the vision that inspires the European 

 powers-that-be in their official aid to the develop- 

 ment of the airship. 



THE TRUE FLYING MACHINE 



Even the most powerful dirigible is, after all, a 

 floating apparatus rather than a true flying machine. 

 It owes its buoyancy to the fact that it displaces more 

 than its own weight of air; therefore it rises on the 

 same principle that causes the rise of the child's toy 

 balloon. In directing its course upward or down- 

 ward, as well as laterally, the influence of guiding 

 planes or rudders is of course necessary, and the pro- 

 peller blades, driven by powerful gasoline engines, 

 grip the air precisely as the propellers of a steamship 



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