MILITARY AERONAUTICS SQUIER. 127 



der. It is balanced. Two pairs of movable horizontal planes, 8 feet 

 by 4 feet, each placed at the front, serve to guide the airship up and 

 down, as in the Patrie and Ville de Paris. These planes have addi- 

 tional inclined surfaces, which are intended to increase the stability 

 in a vertical plane. All these planes, both fixed and movable, are 

 constructed like kites, of silk stretched on bamboo frames. The guide 

 rope is 150 feet long. Speed attained, about 16 miles per hour. This 

 airship with a few improvements added has been in operation the 

 past few months. The steel framework connecting the gas bag to 

 the car is now entirely covered with canvas, which must reduce the 

 resistance of the air very materially. The canvas covering, inclosing 

 the entire bag, serves as a reinforcement to the latter and at the 

 same time gives attachment to the suspension underneath. It is re- 

 jDorted that a speed of 20 miles an hour has been attained with the 

 reconstructed airship. 



A pyramidal construction similar to that on the Patrie has been 

 built under the center of the car to protect the car and propellers on 

 landing. A single movable horizontal plane placed at the front end 

 of the car and operated by the pilot, controls the vertical motion. 



Germany. 



Three different types of airships are being developed in Germany. 

 The Gross is the design of Major Von Gross, who commands the 

 balloon battalion at Tegel, near Berlin, The Parse val is being de- 

 veloped by Major Von Parse val, a retired German officer, and the 

 Zeppelin is the design of Count Zeppelin, also a retired officer of the 

 German army. 



The Gross. 



The first airship of this type made its first ascension on July 23, 

 1907. The mechanical part was built at Siemen's Electrical Works 

 in Berlin ; the gas bag by the Kiedinger firm in Augsburg. 



Gas hag. — The gas bag is made of rubber cloth furnished by the 

 Continental Tire Company, similar to that used in the Ville de Paris. 

 It is diagonal thread, but there is no inner layer of rubber, as they 

 do not fear damage' from impurities in the hydrogen gas. Length, 

 131:^ feet; maximum diameter, about 30^ feet; volume, 03,576 cubic 

 feet. The elongation is about 3^. The form is cylindrical with 

 spherical cones at the ends, the whole being symmetrical. 



Suspension. — The suspension is ^practically the same as that of the 

 Patrie. A steel and aluminum frame is attached to the lower part of 

 the gas bag, and the car is suspended on this by steel cables. The ob- 

 jection to this system is even more apparent in the Gross than in the 

 Patrie. A marked dip along the upper meridian of the gas bag 

 shows plainly the deformation. 



