"Then why should I be in need of gas?"
As a matter of scientific curiosity I may relate that I did not either lose or sacrifice a cubic foot of gas or a single pound of ballast that whole afternoon—nor has that experience been at all exceptional in the very practical little "No. 9" or even in its predecessors. It will be remembered that on the day succeeding the winning of the Deutsch prize my chief mechanician found that the balloon of my "No. 6" would take no gas because none had been lost.
After leaving my fellow-clubmen at St Cloud that afternoon I made a typically practical trip. To go from Neuilly St James to the Aéro Club's grounds I had already passed the Seine. Now, crossing it again, I made the café-restaurant of "The Cascade," where I stopped for refreshments. It was by this time 5 P.M. Not wishing to return yet to my station I crossed the Seine for a third time and went in a straight course as close to the great fort of Mount Valerien as delicacy permitted. Then, returning, I traversed the river once again and came to earth in my own grounds at Neuilly.
During the whole trip my greatest altitude was 105 metres (346 feet). Taking into consideration that my guide rope hangs 40 metres (132 feet) below me, and that the tops of the Bois trees extend up some 20 metres (70 feet) from the ground, this extreme altitude left me but 40 metres (140 feet) of clear space for vertical manœuvring.
It was enough; and the proof of it is that I do not go higher on these trips of pleasure and experiment. Indeed, when I hear of dirigibles going up 400 metres (1300 feet) in the air without some special justifying object I am filled with amazement. As I have already explained, the place of the dirigible is, normally, in low altitudes; and the ideal is to guide-rope on a sufficiently low course to be left free from vertical manœuvring. This is what M. Armengaud, Jeune, referred to in his learned inaugural discourse delivered before the Société Française de Navigation Aérienne in 1901, when he advised me to quit the Mediterranean and go guide-roping over great plains like that of La Beauce.
"No. 9" JUMPING MY WALL
It is not necessary to go to the plain of La Beauce. One can guide-rope even in the centre of Paris if one goes about it at the proper moment. I have done it.
I have guide-roped round the Arc de Triomphe and down the Avenue des Champs Elysées at as low an altitude as the house-tops on either side, fearing no ill and finding no difficulty. My first flight of this kind occurred when I sought for the first time to land in my "No. 9" in front of my own house door, at the corner of the Avenue des Champs Elysées and the Rue Washington, on Tuesday, 23rd June 1903.
Knowing that the feat must be accomplished at an hour when the imposing pleasure promenade of Paris would be least encumbered, I had instructed my men to sleep through the early part of the night in the air-ship station at Neuilly St James so as to be able to have the "No. 9" ready for an early start at dawn. I myself rose at 2 A.M., and in my handy electric automobile arrived at the station while it was yet dark. The men still slept. I climbed the wall, waked them, and succeeded in quitting the earth on my first diagonally upward course over the wall and above the River Seine before the day had broken. Turning to the left, I made my way across the Bois, picking out the open spaces so as to guide-rope as much as possible.