Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/207

Rh THE BALLOON.] AERONAUTICS 189 .scent of jven per- 3iis at .yons. .mencan srostatic sperimeut i 1783. Remarks a the dis- Dvery of ie balloon. to let go, and the balloon being thus so greatly lightened, ascended very rapidly to a height of about 2 miles. After staying in the air about half-an-hour, he descended 3 miles from the place of ascent, although he believed the distance traversed, owing to different currents, to have been about 9 miles. In this second journey M. Charles experienced a violent pain in his right ear and jaw, no doubt produced by the rapidity of the ascent. He also witnessed the phenomenon of a double sunset on the same day ; for when he ascended, the sun had set in the valleys, and as he mounted he saw it rise again, and set a second time as he descended. All the features of the modern balloon as now used are more or less due to Charles, who invented the valve at the top, suspended the car from a hoop, which was itself at tached to the balloon by netting, etc. The M. Robert who accompanied him in the ascent was one of the brothers who had constructed it. On January 19, 1784, the largest balloon on record (if the contemporary accounts are correct) ascended from Lyons. It was more than 100 feet in diameter, about 130 feet in height, and when distended had a capacity, it is said, of over half -a-mil lion cubic feet. It was called the Flesselles (from the name of its proprietor or owner, we believe), and after having been inflated from a straw fire in seventeen minutes, it rose with seven persons in the car, viz., Joseph Montgolfier, Pilatre de Rozier, Count de Laurencin, Count de Dampierre, Prince Charles de Ligne, Count de Laport d Anglefort, and M. Fontaine, the last gentleman having leaped into the car just as the machine had started. The fire was fed with trusses of straw, and the balloon rose majestically to the height of about 3000 feet, but descended again after the lapse of about a quarter of an hour from the time of starting, in consequence of a rent in the upper part. It is proper here to state that researches on the use of gas for inflating balloons seem to have been carried on at Philadelphia nearly simultaneously with the experiments of the Montgolfiers ; and when the news of the latter reached America, Messrs Rittenhouse and Hopkins, mem bers of the Philosophical Academy of Philadelphia, con structed a machine consisting of forty-seven small hydrogen gas-balloons attached to a car or cage. After several pre liminary experiments, in which animals were let up to a certain height by a rope, a carpenter, one James Wilcox, was induced to enter the car for a small sum of money ; the ropes were cut, and he remained in the air about ten minutes, and only then effected his descent bj r making in cisions in a number of the balloons, through fear of falling into the river, which he was approaching. The improvements that have been made in the manage ment and inflation of balloons in the last ninety years have only had reference to details, so that as far as essential principles are concerned the subject is now in pretty much the same state as it was in 1783. We have therefore ar rived at a point in the history of the balloon where it is well to consider how much the Montgolfiers and Charles owed to their predecessors ; and it is proper here to state that, although we have assigned the invention to the two brothers, Stephen and Joseph as no doubt they both conducted the early experiments together still there is reason to believe that the share of the latter was very small. Stephen, however, although the originator of balloons, does not appear ever to have ascended himself, and Joseph did not repeat the ascent just mentioned in the Flesselles. The Montgolfiers had studied Priestley s Ex periments relating to different kinds of Air, Avhence they first conceived the possibility of navigating the atmosphere ; but their experiment was so simple as to require scarcely any philosophical knowledge. They had seen smoke ascend, and thought that if they could imprison it in a bag, the bag might ascend too ; and the observation and reasoning were both such as might occur to anybody. This does not detract from their merit; it, on the contrary, adds to it. The fact that millions of persons must have observed the same thing, and had not derived anything practical there from, only enhances the glory of those who in such well- worn tracts did make a discovery; but the simplicity of the invention shows that it is needless to inquire whence the brothers were led to make it, and how far any part of the credit is due to their predecessors. It is scarcely pos sible to imagine anything more remarkable than that the fact that a light bag held over a fire would ascend into the air was not discovered till 1783, notwithstanding that men in all ages had seen smoke ascend from fire (though, of course, the fire-balloon does not ascend for exactly the same reason that smoke does). It might be supposed that the connec tion of the Montgolfiers with a paper manufactory gave them facilities for constructing their experimental balloons of thin paper ; and perhaps such was the case, although we can find no evidence of it. With regard to Charles s substitution of hydrogen gas, there are anticipations that must be noticed. As early as 17GG Cavendish showed that this gas was at least seven times lighter than ordinary air, and it immediately occurred to Dr Black, of Edinburgh, well known as the discoverer of latent heat, that a thin bag filled with hydrogen gas would rise to the ceiling of a room. He provided, accordingly, the allautois of a calf, with the view of showing at a public lecture such a curious experi ment ; but for some reason it seems to have failed, and P&amp;gt;lack did not repeat it, thus allowing a great discovery, almost within his reach, to escape him. Several years afterwards a similar idea occurred to Tiberius Cavallo, who found that bladders, even when carefully scraped, are too heavy, and that China paper is permeable to the gas. But in 1782, the year before the invention of the Mont golfiers, he succeeded in elevating soap-bubbles by in flating them with hydrogen gas. The discovery of fire-balloons might have taken place almost at any time in the world s history, but the substitution of hydrogen gas for heated air could not have been made previously to the latter half of the last century; and although all the honour of an independent discovery belongs to the Mont golfiers, Charles, by his substitution of &quot; inflammable air &quot; for heated air, merely showed himself acquainted with the state of chemical science of his day. Charles never again ascended after his double expedition on the 1st of December 1783. We now return to the history of aerial navigation, and commence with an account of the first ascents of balloons in this country. Although the news of the Aimonay and subsequent experiments in France rapidly spread all over Europe, and formed a topic of general discussion, still it was not till five months after the Montgolfiers had first publicly sent a balloon into the air that any aerostatic experiment was made in England. In November 1783 Count Zambeccari, an Italian, who happened to be in London, made a balloon of oil-silk, 10 feet in diameter, and weighing 11 ft. It was publicly shown for several days, and on the 25th it was three-quarters filled with hydrogen gas, and launched from the Artillery ground at one o clock. It descended after two hours and a half near Petworth, in Sussex, 48 miles from London. This was the first balloon that ascended from English ground. On February 22, 1784, a hydrogen gas balloon, 5 feet in diameter, was let up from Sandwich, in Kent, and de scended at Warneton, in French Flanders, 75 miles distance. This was the first balloon that crossed the Channel. The difficulties and dangers of aerial navi gation having been surmounted by the end of the year Dr Bl; experi ineuts. Cavall inflate soap b bles w hydros gas in 1782. First ascent balloo