316 SCIENCE OF HOME AND COMMUNITY 



warped so as to steer the machine up and down. In the 

 later machines these planes are mounted in the rear. At 

 the rear also there are two vertical rudders for steering the 

 machine to the right and left. The balance is maintained 

 by warping the rear corners of the wings, which are made 

 movable. A single lever controls both the warping of the 

 wings and the action of the two vertical rudders. 



On the frame between the two main wings are carried the 

 engine and the seats for the operator and passenger. The 

 machine weighs 900 pounds and is driven by a 25 horse 

 power gasoline engine, which turns two twin-bladed pro- 

 pellers in opposite directions at the rate of 400 revolutions 

 a minute. If anything should happen to stop the engine 

 while in the air, the machine can glide to the ground and 

 land safely. The later machines are provided with wheels 

 for starting and alighting. 



Comparison of airship and airplane. In comparing the 

 airship and airplane, we find that each has its advantages. 

 The airship is safer, can carry a much greater weight, and 

 can stay in the air longer. On the other hand, the airplane 

 can travel faster and is much smaller and cheaper to 

 make. We might perhaps compare the airship with the 

 freight train that carries heavy loads and the airplane with 

 the express train that carries lighter loads and travels 

 faster. 



There seems little question that within a short tirr.o 

 regular passenger routes by means of airships and airplanes 

 will be established in this country, and that we may socn 

 have the novel sensation of traveling through the air faster 

 than the express train travels. And all the time we shall 

 be enjoying a magnificent view of the country over which 

 we are passing. 



Shortly after the signing of the armistice in November, 

 1918, there was established an air passenger service between 

 London and Paris. The journey takes only 2\ hours. Dur- 



