With respect to combinations of vertical and horizontal movements, man is absolutely without experience of them. Therefore, as all our sensations of movement are practically in two dimensions, this is the extraordinary novelty of aerial navigation that it affords us experiences—not in the fourth dimension, it is true—but in what is practically an extra dimension—the third—so that the miracle is similar. Indeed, I cannot describe the delight, the wonder, and intoxication of this free diagonal movement onward and upward or onward and downward, combined at will with brusque changes of direction horizontally when the air-ship answers to a touch of the rudder! The birds have this sensation when they spread their great wings and go tobogganning in curves and spirals through the sky!

Por mares nunca d'antes navegados!
(O'er seas hereto unsailed.)

The line of our great poet echoed in my memory from childhood. After this first of all my cruises I had it put on my flag.

It is true that spherical ballooning had prepared me for the mere sensation of height; but that is a very different matter. It is, therefore, curious that, prepared on this head as I was, the mere thought of height should have given me my only unpleasant experience. What I mean is this:

The wonderful new combinations of vertical and horizontal movements, utterly out of previous human experience, caused me neither surprise nor trouble. I would find myself ploughing diagonally upward through the air with a kind of instinctive liberty. And yet when moving horizontally—as you would say, in the natural position—a glance downwards at the house-tops disquieted me.

THE HOUSETOPS LOOK SO DANGEROUS

"What if I should fall?" the thought came. The house-tops looked so dangerous with their chimney-pots for spikes. One seldom has this thought in a spherical balloon, because we know that the danger in the air is nil: the great spherical balloon can neither suddenly lose its gas nor burst. My little air-ship balloon had to support not only exterior but interior pressure as well—which is not the case with a spherical balloon, as I shall explain in the next chapter—and any injury to the cylindrical form of my air-ship balloon by loss of gas might prove fatal.

While over the house-tops I felt that it would be bad to fall, but as soon as I left Paris and was navigating over the forest of the Bois de Boulogne the idea left me entirely. Below there seemed to be an ocean of greenery, soft and safe.

It was while over the continuation of this greenery in the grassy pelouse of the Longchamps racecourse that my balloon, having lost a great deal of its gas, began to double on itself. Previously I had heard a noise. Looking up, I saw that the long cylinder of the balloon was beginning to break. Then I was astonished and troubled. I wondered what I could do.