General Balloon Company.
I had expected to find our starting-point in some open space, or at least in one of the squares, and was therefore not a little surprised to see that this building was situated in one of the most densely populated neighbourhoods. Perhaps, thought I, this is merely the office where the tickets have to be taken. But when I got nearer, I perceived that the building differed essentially from other houses in this respect, that it had an entirely flat roof, which contained a kind of conveyance, not unlike a ship, but the precise outline of which I could not discover, owing to the glass vault over the street.
Bacon and Miss Phantasia were already on the spot, and after the customary morning greetings we entered to secure our seats. The first thing now was to be weighed; for the price of the passage naturally depended on the volume of our bodily organization. It need not be said that the young lady came off cheapest. We then passed through a door into a small parlour, or waiting-room, where we found a few more passengers. In the centre of the room I noticed a staircase, and up at the ceiling a kind of trap. Against the walls were several cushioned seats, as in a first-class railway carriage. After a short time the whole apartment seemed to move. I heard a gentle rustling along the walls, as if something were sliding down the paper-hangings. But even before I had time to think on the subject there was a lowering of the trap in the ceiling, and a cheerful greeting of “Welcome a-high, ladies and gentlemen!”
We got upstairs through the aperture, and found ourselves on the flat roof of the building, but precisely underneath the air-ship; we entered, however, the open trap constructed in the latter, for we soon found out that the weather was bitterly cold. This, unfortunately, prevented me from becoming more intimately acquainted with the outward appearance of the balloon, and with its locomotive powers. On the other hand, ample opportunity was afforded us for examining its internal arrangements. As soon as we came into what I can but term the “hold” of the vessel, Bacon called my attention to a long narrow cylinder which ran across the whole length of the ship. “Therein lies,” said he, “the whole secret of aëronautics. In order that I may explain this to you, I must remind you of this, that it was formerly impossible to steer any balloon except before the wind. An ordinary vessel, when the keel cuts through the water, can sail half or quarter-wind, because she moves in the two intermediate matters of air and water, the latter offering a greater resistance than the former, and thereby supporting the vessel in her movements; to which must be added that the resistance operates in a definite direction, namely, in that of the motion of the ship, so that by supplying the craft with a rudder or helm one is able to turn her at pleasure to the right or the left.
“But,” continued Bacon, “this becomes quite a different matter when a vessel is merely surrounded by air. Driven onward by the wind, which means carried along by the atmospheric current, she meets with no resistance, and therefore lacks every point of support whereby to turn herself. She will always offer the largest of her sides to the wind, which falls upon it at right angles, just the same as on a light piece of paper or cloth whirled round by the wind.
“In order, then, to render such balloon voyages possible at all, it was necessary, in the first place, to afford the machine its required support, its resistance, and this was accomplished in the following manner: The long cylinder which runs along the whole of the ship is a bar of malleable iron, surrounded by a spiral copper wire which has been coated with an insulating substance. If, now, a voltaic current is made to pass along that wire, the bar becomes a most powerful electro-magnet, which, when free in its movements, like the needle of a compass, adopts a direction from south to north, with a slight easterly deviation, and also a certain inclination. When driven out of its natural direction by another power, the needle will endeavour to resume its original inclination. As, now, the magnet and the vessel are so joined together as virtually to form but one body, the balloon, or rather the ship, is in itself a gigantic compass. The inclination is removed just the same as with the needle of the compass. One has merely to alter the centre of gravity, and this can be done in several ways. Thus, all that remains is the direction in the magnetic meridian.
“If, now, the wind blows in the same direction that one wishes to travel, then the apparatus is not worked; that is to say, no current is passed through the wire. Should the wind, however, be unpropitious, then the ship is at once changed into a magnet. For example, suppose the wind to be due west, and the sails to be placed at right angles with the wind, then the vessel will be driven neither east nor northward, but towards a point intermediate; just as a vessel at sea when pushed north by the current of the water, and westward by the wind, does not follow either of these directions exclusively, but an intermediate one. It is not difficult, therefore, to perceive that the aëronaut, by the proper joint working of his sails and of the electro-magnetic apparatus, is enabled to turn his ship into any direction he chooses. Nor is that all. The apparatus also serves as a helm or rudder; for as soon as I press this knob the current is at once reversed; the north pole becomes the south pole, and vice versâ. It stands to reason that the vessel must turn under the circumstances, and, of course, according to pleasure; for at any moment the helmsman may interrupt the current, whereby the ship ceases to be a magnet.
“Now, as indeed at sea, the case may be that the wind is too strong, and the power of the magnet insufficient to properly govern the air-ship. In that case we have recourse to those energeiathecs of which I spoke yesterday; these tend to set in circular motion the four-winged screws which you see here and there peeping out of the sides, and this is always done as near as possible at right angles with the direction in which the vessel has a tendency to deviate.
“Thus it is usually possible to keep the ship in the direction required; but should the aëronaut fail in his attempt to do so, even then he has another resource left him which the seaman lacks. He rises or descends with his air-ship in search of a more favourable wind; nor does he do so at hap-hazard, for the meteorological institute has long since issued charts upon which are marked the directions of all the air-currents that will probably be found at any given altitude for any given time. These charts are arranged in the same manner as those formerly published by the institute, which, however, merely showed the probable direction of the wind in the immediate vicinity of the earth’s surface.
“With regard to the modes of ascent and descent, they differ somewhat according to the nature of the various apparatuses, and for these, to explain them to you in detail—by which alone you would understand the differences—we should have to go on deck, and it is so bitterly cold there, that we are better where we are. Suffice it to say that the old clumsy process of throwing out ballast for the purpose of rising has long been dispensed with, since it was found that the measure was merely a partial or momentary one, and slightly unacceptable to the denizens of the earth below. The most appropriate method we have learned from nature; it consists, namely, of an imitation of the operation of the swim-bladder in fishes. The latter accomplish their ascent and descent in the water by a greater or lesser compression of that bladder, or of the air contained in it; some of them having even special compression apparatuses for that object. From this you will easily conclude the application of the aquatic locomotion to that of the navigation in the air.”
This, I must confess, I did not quite see; but many other points in Bacon’s explanation remained to be cleared up. Not a few questions were on the tip of my tongue, but I asked no more. I felt that I was a child of the nineteenth century, too little au courant of the science of modern times to understand all that had been accomplished during the last two hundred years; moreover, I feared that by putting more silly questions I should lower myself in the estimation of my friend.