AERIAL NAVIGATION. 387 



neer, and later by Scliwarz, whose aluminum balloon proved unman- 

 ageable and was smashed in landing. The most ambitious attempt, 

 however, was that of Count Zeppelin, who built in 1900 a monster 

 air-ship 420 feet long and 39 feet in diameter. It was a cylinder with 

 paraboloid ends, but the shape was inferior and almost all the lifting 

 power was frittered away on a internal frame of aluminum, so that 

 the gasoline motor could be of only 33 horse power, and the speed 

 attained has variously been stated at 8 to 18 miles per hour. ISTever- 

 theless the design of Count Zeppelin contained many excellent fea- 

 tures, and a movement is now on foot in Germany to enable him to 

 try again, through means of a popular subscription. The mere size, 

 if he builds again as large, is a great element of success, for as the 

 cubic contents and lift increase as the cube of the dimensions, while 

 the weights increase in a far smaller ratio, a balloon of this great size 

 ought to be able to lift a very powerful motor, and to attain a speed 

 of 30 or more miles per hour. He has shown that the size is not be- 

 yond the possibility of control. 



Meanwhile gasoline motors had been increasing in efficiency and 

 diminishing in weight. The French war department gave no sign 

 and it was reserved for a Brazilian, Mr. Santos Dumont, to show to 

 the Parisians what could be accomplished by equipping an air-ship 

 with a gasoline motor. The history of his triumphs is so present to 

 all minds that it need only be alluded to, but it may be interesting to 

 give some details of the sizes and arrangements of his various balloons. 

 His first idea seems to have been that, in order to make it manageable, 

 a balloon should be made as small as possible, and that it was prac- 

 ticable to disencumber it of many adjuncts hitherto considered indis- 

 pensable. Neglecting to study carefully what had been found out by 

 his predecessors, he had to learn by experience, and he built five bal- 

 loons, all navigables, before he produced in 1901 his No 6, with which 

 he won the Deutsch Prize, by sailing 3% miles and return in half 

 an hour. This balloon was 108 feet long, 20 feet in diameter and was 

 provided with a gasoline motor of 16 horse power which might be driven 

 up to 18 or 20 horse power. While the speed over the ground was 14 

 miles an hour, retarded as it was by a light wind, the speed through 

 the air was about 19 miles an hour, a small but marked advance over 

 any previous performance; but the result would have been still better 

 if the shape had been that of Colonel Eenard's balloon. 



Since then Mr. Santos Dumont has built four new navigable bal- 

 loons. His No. 7, with which he expects to compete at St. Louis in 

 1904, is 160 feet long and 23 feet in diameter and is to be provided 

 with a motor of 60 horse power. His No. 8, which was sold to parties 

 in New York last year. His No. 9, which is his visiting balloon, being 

 only 50 feet long and 18 feet in diameter and provided with a 3 horse 

 power motor. Its speed is only 10 miles an hour, but it is handy to 



