Page:My Airships.djvu/270

 AT half-past two o'clock on the afternoon of the 14th of February 1902 the staunch air-ship which won the Deutsch prize left the aerodrome of La Condamine on what was destined to be its last voyage. Immediately on quitting the aerodrome it began behaving badly, dipping heavily. It had left the balloon house imperfectly inflated, hence it lacked ascensional force. To keep my proper altitude I increased its diagonal pointing and kept the propeller pushing it on upward. The dipping, of course, was due to the counter effort of gravity. In the shaded atmosphere of the aerodrome the air had been comparatively cool. The balloon was now out in the hot, open sunlight. As a consequence, the hydrogen nearest to the silk cover rarefied rapidly. As the balloon had left the aerodrome imperfectly inflated the rarefied hydrogen was able to rush to the highest possible