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Our Surroundings 



Aviators are equipped with parachutes for use in case of acci- 

 dent. These are umbrella-like cloths, to the edges of which many 

 cords are fastened. The other ends of these cords are attached to 

 a waist belt. At ordinary times parachutes are carefully folded 

 and packed into small space, so arranged, however, that they will 

 be released when a cord is pulled, and will open by air pressure. 

 The aviator leaps from his machine and pulls the cord after he has 



Keystone View Company. 



ADMIRAL BYRD'S ANTARCTIC BIPLANE, OVER NEW YORK CITY 

 The pontoons enable the plane to light safely on the water. 



started down, the pressure of the air in the open parachute serving 

 to check his fall. 



SUMMARY 



The floating log, the dugout, the raft, and boats rowed by oars 

 were early used in water navigation. Sailing ships followed. 



The mariner's compass made possible long voyages, led to dis- 

 coveries of new lands, and increased the demand for ship trans- 

 portation. 



