Page:My Airships.djvu/94



Under the combined action of the propeller impulse, of the steering rudder, of the displacement of the guide rope, and of the two sacks of ballast sliding backward and forward as I willed, I had the satisfaction of making my evolutions in every direction—to right and left, and up and down. Such a result encouraged me, and, being inexperienced, I made the great mistake of mounting high in the air to 400 metres (1300 feet), an altitude that is considered nothing for a spherical balloon, but which is absurd and uselessly dangerous for an air-ship under trial. At this height I commanded a view of all the monuments of Paris. I continued my evolutions in the direction of the Longchamps racecourse, which from that day I chose for the scene of my aerial experiments. So long as I continued to ascend the hydrogen increased in volume as a consequence of the atmospheric depression. So by its tension the balloon was kept taut, and everything went well. It was not the same when I began descending. The air pump, which was intended to compensate the contraction of the hydrogen, was of insufficient capacity. The balloon, a long cylinder, all at once began to fold in the middle like a