The Dominion of the Air
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第5章 CHAPTER II. THE INVENTION OF THE BALLOON.(1)

It was a November night of the year 1782, in the little town of Annonay, near Lyons. Two young men, Stephen and Joseph Montgolfier, the representatives of a firm of paper makers, were sitting together over their parlour fire. While watching the smoke curling up the chimney one propounded an idea by way of a sudden inspiration: "Why shouldn't smoke be made to raise bodies into the air?"

The world was waiting for this utterance, which, it would seem, was on the tip of the tongue with many others. Cavendish had already discovered what he designated "inflammable air," though no one had as yet given it its later title of hydrogen gas.

Moreover, in treating of this gas--Dr. Black of Edinburgh, as much as fifteen years before the date we have now arrived at, had suggested that it should be made capable of raising a thin bladder in the air. With a shade more of good fortune, or maybe with a modicum more of leisure, the learned Doctor would have won the invention of the balloon for his own country.

Cavallo came almost nearer, and actually putting the same idea into practice, had succeeded in the spring of 1782 in making soap bubbles blown with hydrogen gas float upwards. But he had accomplished no more when, as related, in the autumn of the same year the brothers Montgolfier conceived the notion of making bodies "levitate" by the simpler expedient of filling them with smoke.

This was the crude idea, the application of which in their hands was soon marked with notable success. Their own trade supplied ready and suitable materials for a first experiment, and, making an oblong bag of thin paper a few feet in length, they proceeded to introduce a cloud of smoke into it by holding crumpled paper kindled in a chafing dish beneath the open mouth. What a subject is there here for an imaginative painter! As the smoky cloud formed within, the bag distended itself, became buoyant, and presently floated to the ceiling.

The simple trial proved a complete success, due, as it appeared to them, to the ascensive power of a cloud of smoke.

An interesting and more detailed version of the story is extant. While the experiment was in progress a neighbour, the widow of a tradesman who had been connected in business with the firm, seeing smoke escaping into the room, entered and stood watching the proceedings, which were not unattended with difficulties. The bag, half inflated, was not easy to hold in position over the chafing dish, and rapidly cooled and collapsed on being removed from it. The widow noting this, as also the perplexity of the young men, suggested that they should try the result of tying the dish on at the bottom of the bag. This was the one thing wanted to secure success, and that good lady, whose very name is unhappily lost, deserves an honoured place in history. It was unquestionably the adoption of her idea which launched the first balloon into space.

The same experiment repeated in the open air proving a yet more pronounced success, more elaborate trials were quickly developed, and the infant balloon grew fast. One worthy of the name, spherical in shape and of some 600 cubic feet capacity, was now made and treated as before, with the result that ere it was fully inflated it broke the strings that held it and sailed away hundreds of feet into the air. The infant was fast becoming a prodigy. Encouraged by their fresh success, the inventors at once set about preparations for the construction of a much larger balloon some thirty-five feet diameter (that is, of about 23,000 cubic feet capacity), to be made of linen lined with paper and this machine, launched on a favourable day in the following spring, rose with great swiftness to fully a thousand feet, and travelled nearly a mile from its starting ground.

Enough; the time was already ripe for a public demonstration of the new invention, and accordingly the 5th of the following June witnessed the ascent of the same balloon with due ceremony and advertisement. Special pains were taken with the inflation, which was conducted over a pit above which the balloon envelope was slung; and in accordance with the view that smoke was the chief lifting power, the fuel was composed of straw largely mixed with wool. It is recorded that the management of the furnace needed the attention of two men only, while eight men could hardly hold the impatient balloon in restraint. The inflation, in spite of the fact that the fuel chosen was scarcely the best for the purpose, was conducted remarkable expedition, and on being released, the craft travelled one and a half miles into the air, attaining a height estimated at over 6,000 feet.

From this time the tide of events in the aeronautical world rolls on in full flood, almost every half-year marking a fresh epoch, until a new departure in the infant art of ballooning was already on the point of being reached. It had been erroneously supposed that the ascent of the Montgolfier balloon had been due, not to the rarefaction of the air within it--which was its true cause--but to the evolution of some light gas disengaged by the nature of the fuel used. It followed, therefore, almost as a matter of course, that chemists, who, as stated in the last chapter, were already acquainted with so-called "inflammable air," or hydrogen gas, grasped the fact that this gas would serve better than any other for the purposes of a balloon. And no sooner had the news of the Montgolfiers' success reached Paris than a subscription was raised, and M. Charles, Professor of Experimental Philosophy, was appointed, with the assistance of M. Roberts, to superintend the construction of a suitable balloon and its inflation by the proposed new method.