End view of Severo’s airship, showing the longitudinal division of the gas-bag to allow the driving shaft of the propellers to be placed at the axis of the balloon.] In the same year Baron Bradsky-Leboun built an airship with partitions in the gas-bag which was just large enough to counterbalance the weight of the ship and its operators. It was lifted or lowered by a propeller working horizontally. Another propeller drove the ship forward. Through some lack of stability the car turned over, throwing out the two aeronauts, who fell 300 feet and were instantly killed. [Illustration: The first Lebaudy airship.] In 1902, a dirigible balloon was built for the brothers Lebaudy by the engineer Juillot and the aeronaut Surcouf. The gas envelope was made cigar-shaped and fastened rigidly to a rigid elliptical keel-shaped floor 70 feet long and 19 feet wide, made of steel tubes--the object being to prevent rolling and pitching. It was provided with both horizontal and vertical rudders. A 35 horse-power Daimler-Mercedes motor was used to turn two twin-bladed screws, each of 9 feet in diameter. Between the 25th of October, 1902, and the 21st of November, 1903, 33 experimental voyages were made, the longest being 61 miles in 2 hours and 46 minutes; 38.7 miles in 1 hour and 41 minutes; 23 miles in 1 hour and 36 minutes. [Illustration: Framing of the floor and keel of the Lebaudy airship.] In 1904 this ship was rebuilt. It was lengthened to 190 feet and the rear end rounded off. Its capacity was increased to 94,000 cubic feet, and a new covering of the yellow calico which had worked so well on the first model was used on the new one. It was coated with rubber both on the outside and inside. The interior air-bag was increased in size to 17,650 cubic feet, and partitioned into three compartments. During 1904 and 1905 30 voyages were made, carrying in all 195 passengers. [Illustration: The car and propellers of the Lebaudy airship.] The success of this airship led to a series of trials under the direction of the French army, and in all of these trials it proved satisfactory. After the 76th successful voyage it was retired for the winter of 1905-6. In November, 1905, the rebuilt Zeppelin airship was put upon trial. While superior to the first one, it met with serious accident, and was completely wrecked by a windstorm in January, 1906. In May, 1906, Major von Parseval’s non-rigid airship passed through its first trials successfully. This airship may be packed into small compass for transportation, and is especially adapted for military use. In plan it is slightly different from previous types, having two air-bags, one in each end of the envelope, and the front end is hemispherical instead of pointed.