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ОглавлениеThe First Public Trial of the Balloon—Montgolfier's Balloon, Annonay, June 5th, 1783
CHAPTER IV.
FIRST PUBLIC TRIAL OF THE BALLOON.
(Montgolfier's Balloon, Annonay, 5th of June, 1783.)
We are accustomed to rank the brothers Joseph and Etienne Montgolfier as equally distinguished in the field of science. The reason for thus associating these two names seems to have been the fraternal friendship which subsisted in an extraordinary degree in the Montgolfier family, rather than any equality of claim which they had to the notice of posterity. After special investigation, we find that Joseph Montgolfier was very superior to his brother, and that it is to him principally, if not exclusively, that we owe the invention of aerostation. Nevertheless, we shall not insist upon this fact; and seeing that a sacred amity always cemented a perfect union in the Montgolfier family, we will regard that union as unbroken in any sense, and will not insinuate that the brother of Montgolfier was undeserving of the honoured rank which in his lifetime he held.
In 1783, the sons of Pierre Montgolfier, a rich papermaker at Annonay department of Ardèche, were already in the prime of life, and it is related of them that their principal occupation was experimenting in the physical sciences. Joseph Montgolfier, after being convinced by a number of minor experiments made in 1782 and 1783, that a heat of 180° rarefied the air and made it occupy a space of twice the extent it occupied before being heated—or, in other words, that this degree of heat diminished the weight of air by one half—began to speculate on what might be the shape and the material of a structure which being filled with air thus heated, would be able to raise itself from the earth in spite of the weight of its own covering.
The Brothers Montgolfier.
His first balloon was a small parallelopiped in very thin taffeta, containing less than seventy-eight cubic inches of air. He made it rise to the roof of his apartment—in November, 1782—at Avignon, where he then happened to be. Having returned some little time after to Annonay, Joseph and his brother performed the same experiment, together in the open air with perfect success. Certain, then, of the new principle, they made a balloon of considerable size, containing upwards of sixty-five feet of heated air. This machine likewise rose, tore away the cords by which it was at first held down, and mounting in the air to the height of from two to three hundred feet, fell upon the neighbouring hills after a considerable flight. The brothers Montgolfier then made a very large and strong balloon, with which they wished to bring their discovery before the public.
The appointed day was the 5th of June, 1783 and the nobility of the vicinity were invited to be present at the experiment. Faujas de Saint Fond, author of "La Description des Expériences de la Machine Aérostatique," published the same year, gives the following account of it:—
"What," says Saint Fond, "was the general astonishment when the inventors of the machine announced that immediately it should be full of gas, which they had the means of producing at will by the most simple process, it would raise itself to the clouds! It must be granted that, in spite of the confidence in the ingenuity and experience of the Montgolfiers, this feat seemed so incredible to those who came to witness it, that the persons who knew most about it—who were, at the same time, the most favourably predisposed in its favour—doubted of its success.
"At last the brothers Montgolfier commenced their work. They first of all began to make the smoke necessary for their experiment. The machine—which at first seemed only a covering of cloth, lined with paper, a sort of sack thirty-five feet high—became inflated, and grew large even under the eyes of the spectator, took consistence, assumed a beautiful form, stretched itself on all sides, and struggled to escape. Meanwhile, strong arms were holding it down until the signal was given, when it loosened itself, and with a rush rose to the height of 1,000 fathoms in less than ten minutes."
It then described a horizontal line of 7,200 feet, and as it had lost a considerable amount of gas, it began to descend quietly. It reached the ground in safety; and this first attempt, crowned with such decisive success, secured for ever to the brothers Montgolfier the glory of one of the most astonishing discoveries.
"When we reflect for a moment upon the numberless difficulties which such a bold attempt entailed, upon the bitter criticism to which it would have exposed its projectors had it failed through any accident, and upon the sums that must have been spent in carrying it out, we cannot withhold the highest admiration for the men who conceived the idea and carried it out to such a successful issue."
Étienne Montgolfier has left us a description of this first balloon. "The aerostatic machine," he says, "was constructed of cloth lined with paper, fastened together on a network of strings fixed to the cloth. It was spherical; its circumference was 110 feet, and a wooden frame sixteen feet square held it fixed at the bottom. Its contents were about 22,000 cubic feet, and it accordingly displaced a volume of air weighing 1,980 lbs. The weight of the gas was nearly half the weight of the air, for it weighed 990 lbs., and the machine itself, with the frame, weighed 500: it was, therefore, impelled upwards with the force of 490 lbs. Two men sufficed to raise it and to fill it with gas, but it took eight to hold it down till the signal was given. The different pieces of the covering were fastened together with buttons and button-holes. It remained ten minutes in the air, but the loss of gas by the button-holes, and by other imperfections, did not permit it to continue longer. The wind at the moment of the ascent was from the north. The machine came down so lightly that no part of it was broken."
