My Airships Part 3

At the bottom of the abyss, which already opened 1500 yards below us, the earth, instead of appearing round like a ball, shows concave like a bowl by a peculiar phenomenon of refraction whose effect is to lift up constantly to the aeronaut's eyes the circle of the horizon.

Villages and woods, meadows and chateaux, pa.s.s across the moving scene, out of which the whistling of locomotives throws sharp notes. These faint, piercing sounds, together with the yelping and barking of dogs, are the only noises that reach one through the depths of the upper air.

The human voice cannot mount up into these boundless solitudes. Human beings look like ants along the white lines that are highways, and the rows of houses look like children's playthings.

While my gaze was still held fascinated on the scene a cloud pa.s.sed before the sun. Its shadow cooled the gas in the balloon, which wrinkled and began descending, gently at first, and then with accelerated speed, against which we strove by throwing out ballast. This is the second great fact of spherical ballooning--we are masters of our alt.i.tude by the possession of a few pounds of sand!

Regaining our equilibrium above a plateau of clouds at about 3000 yards we enjoyed a wonderful sight. The sun cast the shadow of the balloon on this screen of dazzling whiteness, while our own profiles, magnified to giant size, appeared in the centre of a triple rainbow! As we could no longer see the earth all sensation of movement ceased. We might be going at storm speed and not know it. We could not even know the direction we were taking save by descending below the clouds to regain our bearings.

A joyous peal of bells mounted up to us. It was the noonday Angelus ringing from some village belfry. I had brought up with us a substantial lunch of hard-boiled eggs, cold roast beef and chicken, cheese, ice-cream, fruits and cakes, champagne, coffee, and Chartreuse.

Nothing is more delicious than lunching like this above the clouds in a spherical balloon. No dining-room can be so marvellous in its decoration. The sun sets the clouds in ebullition, making them throw up rainbow jets of frozen vapour like great sheaves of fireworks all around the table. Lovely white spangles of the most delicate ice formation scatter here and there by magic; while flakes of snow form, moment by moment, out of nothingness, beneath our very eyes, and in our very drinking-gla.s.ses.

I was finishing my little gla.s.s of liqueur when the curtain suddenly fell on this wonderful stage setting of sunlight, cloud billows, and azure. The barometer rose rapidly 5 millimetres, showing a sudden rupture of equilibrium and a swift descent. Probably the balloon had become loaded down with several pounds of snow, and it was falling into a cloud.

We pa.s.sed into the half darkness of the fog. We could still see our basket, our instruments, and the parts of the rigging nearest us, but the netting that held us to the balloon was visible only to a certain height, and the balloon itself had completely disappeared. So we had for a moment the strange and delightful sensation of hanging in the void without support, of having lost our last ounce of weight in a limbo of nothingness, sombre and portentous.

After a few minutes of fall, slackened by throwing out more ballast, we found ourselves under the clouds at a distance of about 300 yards from the ground. A village fled away from us below. We took our bearings with the compa.s.s, and compared our route map with the immense natural map that unfolded below. Soon we could identify roads, railways, villages, and forests, all hastening toward us from the horizon with the swiftness of the wind itself.

The storm which had sent us downward marked a change of weather. Now little gusts began to push the balloon from right to left, up and down.

From time to time the guide rope--a great rope dangling 100 yards below our basket--would touch earth, and soon the basket, too, began to graze the tops of trees.

What is called "guide-roping" thus began for me under conditions peculiarly instructive. We had a sack of ballast at hand, and when some special obstacle rose in our path, like a tree or a house, we threw out a few handfuls of sand to leap up and pa.s.s over it. More than 50 yards of the guide rope dragged behind us on the ground; and this was more than enough to keep our equilibrium under the alt.i.tude of 100 yards, above which we decided not to rise for the rest of the trip.

This first ascent allowed me to appreciate fully the utility of this simple part of the spherical balloon's rigging, without which its landing would usually present grave difficulties. When, for one reason or another--humidity gathering on the surface of the balloon, a downward stroke of wind, accidental loss of gas, or, more frequently, the pa.s.sing of a cloud before the face of the sun--the balloon came back to earth with disquieting speed, the guide rope would come to rest in part on the ground, and so, unballasting the whole system by so much of its weight, stopped, or at least eased, the fall. Under contrary conditions any too rapid upward tendency of the balloon was counterbalanced by the lifting of the guide rope off the ground, so that a little more of its weight became added to the weight of the floating system of the moment before.

Like all human devices, however, the guide rope, along with its advantages, has its inconveniences. Its rubbing along the uneven surfaces of the ground--over fields and meadows, hills and valleys, roads and houses, hedges and telegraph wires--gives violent shocks to the balloon. Or it may happen that the guide rope, rapidly unravelling the snarl in which it has twisted itself, catches hold of some asperity of the surface or winds itself around the trunk or branches of a tree.

Such an incident was alone lacking to complete my instruction.

As we pa.s.sed a little group of trees a shock stronger than any hitherto felt threw us backward in the basket. The balloon had stopped short, and was swaying in the wind gusts at the end of its guide rope, which had curled itself around the head of an oak. For a quarter of an hour it kept us shaking like a salad-basket, and it was only by throwing out a quant.i.ty of ballast that we finally got ourselves loose. The lightened balloon made a tremendous leap upward and pierced the clouds like a cannon-ball. Indeed, it threatened to reach dangerous heights, considering the little ballast we had remaining in store for use in descending. It was time to have recourse to effective means, to open the manoeuvre valve and let out a portion of our gas.

It was the work of a moment. The balloon began descending to earth again, and soon the guide rope again rested on the ground. There was nothing to do but to bring the trip to an end, because only a few handfuls of sand remained to us.

He who wishes to navigate an air-ship should first practise a good many landings in a spherical balloon--that is, if he wishes to land without breaking balloon, keel, motor, rudder, propeller, water-ballast cylinders, and fuel holders. The wind being rather strong, it was necessary to seek shelter for this last manoeuvre. At the end of the plain a corner of the forest of Fontainebleau was hurrying toward us. In a few moments we had turned the extremity of the wood, sacrificing our last handful of ballast. The trees now protected us from the violence of the wind, and we cast anchor, at the same time opening wide the emergency valve for the wholesale escape of the gas.

The twofold manoeuvre landed us without the least dragging. We set foot on solid ground, and stood there watching the balloon die. Stretched out in the field, it was losing the remains of its gas in convulsive agitations, like a great bird that dies in beating its wings.

After taking a dozen instantaneous photographs of the dying balloon we folded it and packed it in the basket with its netting folded alongside. The little chosen corner in which we had landed formed part of the grounds of the Chateau de la Ferriere, belonging to M. Alphonse de Rothschild. Labourers from a neighbouring field were sent for a conveyance to the village of La Ferriere itself, and half-an-hour later a brake came. Putting everything into it we set off to the railway station, which was some 4 kilometres (2-1/2 miles) distant. There we had some work to lift the basket with its contents to the ground, as it weighed 200 kilogrammes (440 pounds). At 6.30 we were back at Paris, after a journey of 100 kilometres (more than 60 miles), and nearly two hours pa.s.sed in the air.

CHAPTER IV

MY "BRAZIL"--SMALLEST OF SPHERICAL BALLOONS

I liked ballooning so much that, coming back from my first trip with M.

Machuron, I told him that I wanted a balloon built for myself. He liked the idea. He thought that I wanted an ordinary-sized spherical balloon, between 500 and 2000 cubic metres in volume. No one would think of making one smaller.

It is only a short time ago, but it is curious how constructors still clung to heavy materials. The smallest balloon basket had to weigh 30 kilogrammes (66 lbs.). Nothing was light--neither envelope, rigging, nor accessories.

I gave M. Machuron my ideas. He cried out against it when I told him I wanted a balloon of the lightest and toughest j.a.panese silk, 100 cubic metres (about 3500 cubic feet) in volume. At the works both he and M.

Lachambre tried to prove to me that the thing was impossible.

[Ill.u.s.tration: "THE BRAZIL"

SMALLEST OF SPHERICAL BALLOONS]

How often have things been proved to me impossible! Now I am used to it I expect it. But in those days it troubled me. Still I persevered.

They showed me that for a balloon to have "stability" it must have a certain weight. Again, a balloon of 100 cubic metres, they said, would be affected by the movements of the aeronaut in his basket much more than a large balloon of regulation size.

[Ill.u.s.tration: Fig. 1.]

[Ill.u.s.tration: Fig. 2.]

With a large balloon the centre of gravity in the weight of the aeronaut is as in Fig. 1, _a_. When the aeronaut moves, say, to the right in his basket, Fig. 1, _b_, the centre of gravity of the whole system is not shifted appreciably.

In a very small balloon the centre of gravity, Fig. 2, _a_, is undisturbed only so long as the aeronaut sits straight in the centre of his basket. When he moves to the right the centre of gravity, Fig. 2, _b_, is shifted beyond the vertical line of the balloon's circ.u.mference, causing the balloon to swing in the same direction.

Therefore, they said, your necessary movements in the basket will cause your little balloon to roll and swing continually.

"We shall make the suspension tackle longer in proportion," I replied.

It was done, and the "Brazil" proved remarkably stable.

When I brought my light j.a.panese silk to M. Lachambre he looked at it and said: "It will be too weak." But when we came to try it with the dynamometer it surprised us. Tested thus, Chinese silk stands over 1000 kilogrammes (or 2200 lbs.) strain to the linear metre (33 feet). The thin j.a.panese silk stood a strain of 700 kilogrammes (1540 lbs.)--that is, it proved to be thirty times stronger than necessary according to the theory of strains. This is astonishing when you consider that it weighs only 30 grammes (a little more than one ounce) per square metre.

To show how experts may be mistaken in their merely off-hand judgments I have been building my air-ship balloons of this same material; yet the inside pressure they have to stand is enormous, while all spherical balloons have a great hole in the bottom to relieve it.

As the proportions finally adopted for the "Brazil" were 113 cubic metres (4104 cubic feet), corresponding to about 113 square metres (135 square yards) of silk surface, the whole envelope weighed scarcely 3-1/2 kilogrammes (less than 8 lbs.). But the weight of the varnish, three coats, brought it up to 14 kilogrammes (about 31 lbs.). The net, which often weighs into the hundreds of lbs., weighed 1800 grammes, or nearly 4 lbs. The basket, which usually weighs 30 kilogrammes (66 lbs.) at a minimum, weighed 6 kilogrammes (13 lbs.); the basket which I now have with my little "No. 9" weighs less than 5 kilogrammes (11 lbs.). My guide rope, small, but very long--100 yards--weighed at most 8 kilogrammes (17-1/2 lbs.); its length gave the "Brazil" a good spring.

Instead of an anchor I put in a little grappling-iron of 3 kilogrammes (6-1/2 lbs.).

Making everything light in this way I found that, in spite of the smallness of the balloon, it would have ascensional force to take up my own weight of 50 kilogrammes (110 lbs.) and 30 kilogrammes (66 lbs.) of ballast. As a fact, I took up that amount on my first trip. On another occasion, when a French Cabinet Minister was present, anxious to see the smallest spherical balloon ever made, I had practically no ballast at all, only 4 or 5 kilogrammes (10 or 11 lbs.). Nevertheless, causing the balloon to be weighed, I went up, and made a good ascent.

The "Brazil" was very handy in the air--easy to control. It was easy to pack also on descending, and the story that I carried it in a valise is true.

Before starting out in my little "Brazil" I made from twenty-five to thirty ascents in ordinary spherical balloons, quite alone, as my own captain and sole pa.s.senger. M. Lachambre had many public ascents, and allowed me to do some of them for him. Thus I made ascents in many parts of France and Belgium. As I got the pleasure and the experience, and as I saved him the labour and paid all my own expenses and damages, it was a mutually advantageous arrangement.

I do not believe that, without such previous study and experience with a spherical balloon, a man can be capable of succeeding with an elongated dirigible balloon, whose handling is so much more delicate.

Before attempting to direct an air-ship it is necessary to have learned in an ordinary balloon the conditions of the atmospheric medium, to have become acquainted with the caprices of the wind, and to have gone thoroughly into the difficulties of the ballast problem from the triple point of view of starting, of equilibrium in the air, and of landing at the end of the trip.

To have been oneself the captain of an ordinary balloon at the very least a dozen times seems to me an indispensable preliminary to acquiring an exact notion of the requisites for constructing and handling an elongated balloon furnished with its motor and propeller.

Naturally, I am filled with amazement when I see inventors, who have never set a foot in the basket, drawing up on paper--and even executing in whole or in part--fantastic air-ships, whose balloons are to have a capacity of thousands of cubic metres, loaded down with enormous motors which they do not succeed in raising from the ground, and furnished with machinery so complicated that nothing works! Such inventors are afraid of nothing, because they have no idea of the difficulties of the problem. Had they previously journeyed through the air at the wind's will, and amid all the disturbing influences of atmospheric phenomena, they would understand that a dirigible balloon, to be practical, requires first of all to have the utmost extreme of simplicity in all its mechanism.

Some of the unhappy constructors who have paid with their lives the forfeit of their rashness had never made a single responsible ascent as captain of a spherical balloon! And the majority of their emulators, now so devotedly labouring, are in the same inexperienced condition. This is my explanation of their lack of success. They are in the condition in which the first-comer would find himself were he to agree to build and steer a transatlantic liner without having ever quitted land or set foot in a boat!

CHAPTER V