My Airships Part 6

Of course, when starting, or shortly after leaving the ground, one has sometimes to throw out ballast to balance the machine, as one may have made a mistake and started with the air-ship far too heavy. What I have referred to are manoeuvres in the air.

[Ill.u.s.tration: "No. 4" FREE DIAGONAL MOVEMENT UP]

[Ill.u.s.tration: "No. 6." FREE DIAGONAL MOVEMENT DOWN]

My first impression of aerial navigation was, I confess, surprise to feel the air-ship going straight ahead. It was astonishing to feel the wind in my face. In spherical ballooning we go with the wind, and do not feel it. True, in rising and descending the spherical balloonist feels the friction of the atmosphere, and the vertical oscillation makes the flag flutter, but in the horizontal movement the ordinary balloon seems to stand still, while the earth flies past under it.

As my air-ship ploughed ahead the wind struck my face and fluttered my coat, as on the deck of a transatlantic liner, though in other respects it will be more accurate to liken aerial to river navigation with a steamboat. It is not like sail navigation, and all talk about "tacking"

is meaningless. If there is any wind at all it is in a given direction, so that the a.n.a.logy with a river current is complete. When there is no wind at all we may liken it to the navigation of a smooth lake or pond.

It will be well to understand this matter.

Suppose that my motor and propeller push me through the air at the rate of 20 miles an hour, I am in the position of a steamboat captain whose propeller is driving him up or down the river at the rate of 20 miles an hour. Imagine the current to be 10 miles per hour. If he navigates against the current he accomplishes 10 miles an hour with respect to the sh.o.r.e, though he has been travelling at the rate of 20 miles an hour through the water. If he goes with the current he accomplishes 30 miles an hour with respect to the sh.o.r.e, though he has not been going any faster through the water. This is one of the reasons why it is so difficult to estimate the speed of an air-ship.

It is also the reason why air-ship captains will always prefer to navigate for their own pleasure in calm weather, and, when they find an air current against them, will steer obliquely upward or downward to get out of it. Birds do the same thing. The sailing yachtsman whistles for a fair breeze, without which he can do nothing, but the river steamboat captain will always hug the sh.o.r.e to avoid the freshet, and will time his descent of the river by the outgoing, rather than the incoming, tide. We air-shipmen are steamboat captains and not sailing yachtsmen.

The navigator of the air, however, has the one great advantage--he can leave one current for another. The air is full of varying currents.

Mounting, he will find an advantageous breeze or else a calm. These are strictly practical considerations, having nothing to do with the air-ship's ability to battle with the breeze when obliged to do it.

Before going on my first trip I had wondered if I should be sea-sick.

I foresaw that the sensation of mounting and descending obliquely with my shifting weights might be unpleasant. And I looked forward to a good deal of pitching (_tangage_), as they say on board ship--of rolling there would not be so much--but both sensations would be novel in ballooning, for the spherical balloon gives no sensation of movement at all.

In my first air-ship, however, the suspension was very long, approximating that of a spherical balloon. For this reason there was very little pitching. And, speaking generally, since that time, though I have been told that on this or that trip my air-ship pitched considerably, I have never been sea-sick. It may be due in part to the fact that I am rarely subject to this ill upon the water. Back and forth between Brazil and France and between France and the United States I have had experience of all kinds of weather. Once, on the way to Brazil, the storm was so violent that the grand piano went loose and broke a lady's leg, yet I was not sea-sick.

I know that what one feels most distressingly at sea is not so much the movement as that momentary hesitation just before the boat pitches, followed by the malicious dipping or mounting, which never comes quite the same, and the shock at top and bottom. All this is powerfully aided by the smells of the paint, varnish, tar, mingled with the odours of the kitchen, the heat of the boilers, and the stench of the smoke and the hold.

In the air-ship there is no smell--all is pure and clean--and the pitching itself has none of the shocks and hesitations of the boat at sea. The movement is suave and flowing, which is doubtless owing to the lesser resistance of the air waves. The pitches are less frequent and rapid than those at sea; the dip is not brusquely arrested, so that the mind can antic.i.p.ate the curve to its end; and there is no shock to give that queer, "empty" sensation to the solar plexus.

Furthermore, the shocks of a transatlantic liner are due first to the fore, and then to the after, part of the giant construction rising out of the water to plunge into it again. The air-ship never leaves its medium--the air--in which it only swings.

This consideration brings me to the most remarkable of all the sensations of aerial navigation. On my first trip it actually shocked me! This is the utterly new sensation of movement in an extra dimension!

Man has never known anything like free vertical existence. Held to the plane of the earth, his movement "down" has scarcely been more than to return to it after a short excursion "up," our minds remaining always on the plane surface even while our bodies may be mounting; and this is so much the case that the spherical balloonist as he rises has no sense of movement, but gains the impression that the earth is descending below him.

_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.

[Ill.u.s.tration: 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 gra.s.sy _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.

I could not think of anything to do. I might throw out ballast. That would cause the air-ship to rise, and the decreased pressure of the atmosphere would doubtless permit the expanding gas to straighten out the balloon again taut and strong. But I remembered that I must always come down again when all the danger would repeat itself, and worse even than before, from the more gas I should have lost. There was nothing to do but to go on down instantly.

I remember having the sure idea: "If that balloon cylinder doubles any more, the ropes by which I am suspended to it will work at different strengths and will begin to break one by one as I go down!"

For the moment I was sure that I was in the presence of death. Well, I will tell it frankly, my sentiment was almost entirely that of waiting and expectation.

"What is coming next?" I thought. "What am I going to see and know in a few minutes? Whom shall I see after I am dead?"

[Ill.u.s.tration: OVER THE BOIS DE BOULOGNE. BELOW THERE SEEMED TO BE AN OCEAN OF GREENERY, SOFT AND SAFE]

The thought that I should be meeting my father in a few minutes thrilled me. Indeed, I think that in such moments there is no room either for regret or terror. The mind is too full of looking forward.

One is frightened only so long as one still has a chance.

CHAPTER IX

EXPLOSIVE ENGINES AND INFLAMMABLE GASES

I have been so often and so sincerely warned against what is taken for granted to be the patent danger of operating explosive engines under ma.s.ses of inflammable gases that I may be pardoned for stopping a moment to disclaim undue or thoughtless rashness.

Very naturally, from the first, the question of physical danger to myself called for consideration. I was the interested party, and I tried to view the question from all points. Well, the outcome of these meditations was to make me fear fire very little, while doubting other possibilities against which no one ever dreamed of warning me.

[Ill.u.s.tration: THE QUESTION OF PHYSICAL DANGER]

I remember that while working on the first of all my air-ships in that little carpenter shop of the Rue du Colisee I used to wonder how the vibrations of the petroleum motor would affect the system when it got in the air.

In those days we did not have the noiseless automobiles, free from great vibration, of the present. Nowadays, even the colossal 80 and 90 horse-power motors of the latest racing types can be started and stopped as gently as those great steel hammers in iron foundries, whose engineers make a trick of cracking the top of an egg with them without breaking the rest of the sh.e.l.l.

My tandem motor of two cylinders, working the same connecting-rod and fed by a single carburator, realised 3-1/2 horse-power--at that time a considerable force for its weight--and I had no idea how it would act off terra firma. I had seen motors "jump" along the highway. What would mine do in its little basket, that weighed almost nothing, and suspended from a balloon that weighed less than nothing?

You know the principle of these motors? One may say that there is gasoline in a receptacle. Air pa.s.sing through it comes out mixed with gasoline gas, ready to explode. You give a whirl to a crank, and the thing begins working automatically. The piston goes down, sucking combined gas and air into the cylinder. Then the piston comes back and compresses it. At that moment an electric spark is struck. An explosion follows instantly; and the piston goes down, producing work. Then it goes up, throwing out the product of combustion. Thus with the two cylinders there was one explosion for every turn of the shaft.

Wishing to have my mind clear on the question I took my tricycle, just as it was after I had left the Paris-Amsterdam race, and, accompanied by a capable companion, I steered it to a lonely part of the Bois de Boulogne. There in the forest I chose a great tree with low-hanging limbs. From two of them we suspended the motor tricycle by three ropes.

When we had well established the suspension my companion aided me to climb up and seat myself on the tricycle saddle. I was as in a swing.

In a moment I would start the motor and learn something of my future success or failure.

Would the vibration of the explosive engine shake me back and forth, strain at the ropes until it had unequalised their tension, and then break them one by one? Would it jar the interior air balloon's pump and derange the big balloon's valves? Would it continually jerk and pull at the silk hems and the thin rods which were to hold my basket to the balloon? Free from the steadying influence of the solid ground, would the jumping motor jar itself until it broke? And, breaking, might it not explode?

All this and more had been predicted by the professional aeronauts, and I had as yet no proof outside of reasoning that they might not be right on this or that topic.

I started the motor. I felt no particular vibration, and I was certainly not being shaken. I increased the speed, and felt _less_ vibration!