Part 6 (1/2)
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-s.h.i.+p 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-s.h.i.+p going straight ahead. It was astonis.h.i.+ng 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-s.h.i.+p 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-s.h.i.+p.
It is also the reason why air-s.h.i.+p 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-s.h.i.+pmen 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-s.h.i.+p'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 s.h.i.+fting weights might be unpleasant. And I looked forward to a good deal of pitching (_tangage_), as they say on board s.h.i.+p--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-s.h.i.+p, 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-s.h.i.+p 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-s.h.i.+p 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-s.h.i.+p 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-s.h.i.+p 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]