304 SCIENCE OF HOME AND COMMUNITY 



were developed that much progress was made in air navi- 

 gation. 



The first successful journey in a dirigible balloon was 

 made in France in 1884. Although this was a short journey 

 of only two or three miles and return, it showed the possi- 

 bilities that there are in this kind of airship. During the 

 last fifteen or twenty years great strides have been made 

 in the development of airships, France and Germany taking 

 the lead. 



Santos Dumont. Santos Dumont was the first man to 

 attain any great success with airships. He was a Brazilian 

 by birth, but he carried on most of his experiments in 

 France. He began his experiments about 1898 and his 

 many remarkable successes attracted much attention. One 

 of the chief of these was his trip around the Eiffel Tower 

 and return to his starting place. 



Zeppelins. Modern airships are of three types, rigid, 

 non-rigid, and semi-rigid. The best known of the rigid type 

 are those of Count Zeppelin of Germany, who began ex- 

 perimenting with airships about 1898. The success he has 

 attained since then is well known the world over. He began 

 the construction of airships of a gigantic size, much larger 

 than had ever before been attempted. 



The framework of the Zeppelin is made of aluminum, and 

 it is divided into separate compartments, each of which con- 

 tains a gas bag filled with hydrogen gas. Suspended from 

 this trame are two boat-shaped cars between which is a 

 weight running on a rail, by which the balance of the ship 

 fore and aft can be adjusted. The ship is driven by means 

 of four propellers, ten feet in diameter, each with three blades. 

 These are turned by two powerful engines of no horse 

 power, one in each car. 



At the rear end are two planes, which give greater sta- 

 bility when the airship is traveling rapidly. Steering up 

 and down is effected by means of elevating planes, and steer- 



