Engineering Wonders of the World
Volume III

58 ENGINEERING WONDERS OF THE WORLD. FRENCH NON-RIGID AIRSHIP “ VILLE DE PARIS.” LARGE TRACTOR SCREW IN FRONT. Length, 62 metres; greatest diameter, 10'5 metres; volume, 3,200 cubic metres; horse-power of motor, 70. {Photo, Topical.) is divided fore and aft into three compart- ments by curtains of permeable cloth, not fixed at the bottom, so that The Ville w]ien ballonet is distended de Paris. . air can pass easily from one compartment to another. The car is very long and heavy, and is attached to the gas- bag by a number of ropes running to canvas bands sewn to the side of the bag. This “ long ” suspension gives a good distribution of weight. A single propeller of large diameter is mounted at the front of the car, and driven by a 75 horse-power motor at 980 revolutions per minute. The distinguishing feature of the Ville de Paris is the eight small cylinders, arranged in groups of two, which take the place of the vertical and horizontal stability planes of the Patrie. Their weight is exactly equal to the buoyancy of the gas which they contain, so that they have no ascensional effect. They are said to serve their purpose very well, but, in spite of their conical for- ward ends, cause a drag which militates against high speed. The Clément-Bayard I., designed by M. A. Clément, the founder of the famous French motor-car firm, was completed in 1908. Length, 56’25 metres ; maximum di- ameter, 10’58 metres ; volume, 3,500 cubic metres. The bag Clément- Bayard I. has at the tail four large pear-shaped gas ballonets, which communicate with the main bag through holes pierced in the envelope. The air ballonet is unusually large, and has a volume of 1,100 cubic metres. The car is built of steel tubes, and covered with cloth and aluminium sheeting. The vertical rudder has two parallel planes of steel ; the hori- zontal rudder three superposed planes, with a total surface of 16 square metres, and is set slightly forward of the centre of gravity. Both rudders are balanced and operated