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of copper, made sufficiently thin to float in the atmosphere, would be utterly unable to resist the external pressure; which being demonstrated, no attempt was made on the principle.

10. In 1709, Friar Guzman applied to the king of Portugal for his patronage of a flying machine constructed somewhat in the form of a bird or paper kite, but with tubes through which the wind was to pass to fill wings that were to elevate it and absurd as this plan obviously was, he met with the royal patronage to such a degree, that he obtained a place in the college of Barcelos, with a professorship in the university of Boimbra, and a pension for life of 6000 reis. But excepting this metaphorical movement upwards to places and honours, we do not hear that the friar ever made any ascent; though it is said, that in 1736, he constructed a large wicker basket covered with paper, seven or eight feet in diameter, which rose 200 feet in the air; and thus came to be reputed a conjurer.

11. It is well remarked by a valuable contemporary, (Sup. Ency. Brit. Art. AERONAUTICS,) that the persons who had hitherto occupied themselves most with attempts at ærial navigation, were all of them Catholic priests. And he enquires whether such a pursuit may be explained from their habits of seclusion, and ignorance of the affairs of real life, or from their familiar acquaintance with the relations of miracles and legendary tales. There can be no question that it arose from these causes in great part, as well as from the fact of religious men during the dark ages, engrossing almost every pretension to knowledge; thus some of the more artful of the priests, imposed on the vulgar the smatterings of natural philosophy as really miraculous facts: and then again in the dawning of the new day of literature, others of their order largely redeemed its credit by nobly dealing forth of their secluded stores of literature and science, and leading on to a brighter day.

12. In 1766, Mr. Henry Cavendish ascertained that inflammable air was at least seven times lighter than common air, and suggested to Dr. Black, that perhaps a thin bag filled with the former might be buoyed up by the common atmosphere. The same thought occurred afterwards to Mr. Cavallo; and he has the honour of being the first who made experiments on the subject. He first tried bladders; but found them too heavy. He then tried Chinese paper; but that proved permeable to the vapour. His experiments, therefore, in 1782, proceeded no farther than blowing up soap bubbles with inflammable air, which ascended rapidly to the ceiling.

13. While the true doctrine of aeronautics seemed thus on the point of being discovered in Britain, it was all at once announced in France, by two brothers, Stephen and John Montgolfier, natives of Annonay, and masters of a considerable paper manufactory there, who had turned their thoughts to this subject, as early as the middle of the year 1782. Their idea was to form an artificial cloud, by enclosing smoke in a bag, and making it carry up the covering along with it. In that year, the experiment was made at Avignon with a fine silk bag; and by apply

ing burning paper to an aperture at the bottom, the air was rarified, and the bag ascended to the height of 70 feet.—Various experiments were now tried upon a large scale, which greatly excited the public curiosity.

14. An immense bag of linen, lined with paper, and containing upwards of 23,000 cubit feet, was found to have the power of lifting about 500 pounds, including its own weight. Burning chopped straw and wool under the aperture of the machine, immediately occasioned it to swell; and afterwards to ascend into the atmosphere. In ten minutes it had risen 6000 feet; and when its force was exhausted, it fell to the ground at the distance of 7668 feet from the place it had left.

15. Not long after this, one of the brothers, invited by the Academy of Sciences to repeat his experiments at their expense, constructed a large balloon of an elliptical form. In a preliminary experiment, this machine lifted from the ground eight persons who held it, and would have carried them all off, if others had not quickly come to their assistance. Next day the machine was filled by the combustion of fifty pounds of straw, and twelve pounds of wool. The machine soon swelled, and sustained itself in the air, together with the charge of between 4 and 500 pounds weight. It was designed to repeat the experiment before the king at Versailles; but a violent storm of rain and wind happening to damage the machine, it became necessary to prepare a new one; and such expedition was used, that this vast balloon, nearly sixty feet in height and fortythree in diameter, was made, painted within and without, and finely decorated, in ninety-six hours. Along with it was sent a wicker cage, containing a sheep, a cock, and a duck, which were the first animals ever sent on such a voyage. The full success of the experiment was, however, prevented by a violent gust of wind, which tore the machine in two places near the top before it ascended. Still it rose 1440 feet; and after remaining in the air about eight minutes, fell to the ground at the distance of 10,200 feet from the place of its setting out. The animals were not in the least hurt.

16. As the great power of these ærostatic machines, and their very gradual descent, now demonstrated they were capable of transporting people through the air with safety, M. Pilatre de Rozier offered to be the first ærial adventurer in a new machine, constructed in a garden in the Fauxbourg of St. Antoine. It was of an oval shape, forty-eight feet in diameter, and seventy-four in height, elegantly painted with the signs of the zodiac, ciphers of the king's name, and other ornaments; a proper gallery, grate, &c. enabled the person who ascended to supply the fire with fuel, and thus keep up the machine as long as he pleased. The weight of the whole apparatus was upwards of 1600 pounds. On the 15th October, 1783, M. Pilatre placing himself in the gallery, the machine was inflated, and permitted to ascend to the height of eightyfour feet, where he kept it afloat about four minutes and half; after which it descended very gently and such was its tendency to ascend, that it rebounded to a considerable height after

touching the ground. On repeating the experiment, he ascended to' the height of 210 feet. His next ascent was 262 feet; and in the descent a gust of wind having blown the machine over some large trees in an adjoining garden, M.Pilatre suddenly extricated himself by throwing straw and wool on the fire, which raised him at once to a sufficient height. On descending again, he once more raised himself to a proper height by the same means. The balloon was constructed by the Montgolfiers, and the spirited young naturalist who thus first ascended, seems to have caught at the moment of its filling, a sort of enthusiasm that prompted him to seat himself in the gallery, and to become the leader of these sublime experiments. Some time after, he ascended with M. Girand de Villette to the height of 330 feet; hovering over Paris at least nine minutes in sight of all the inhabitants, and the machine keeping all the while in a steady position.

17. It was now proved that ærostatic machines might be raised or lowered at the pleasure of the persons who ascended. On the 21st of November, 1783, therefore, M. Pilatre and the Marquis d'Arlandes undertook an ærial voyage, which lasted about twenty-five minutes, and during which time, they passed over a space of five miles. From the account given by the Marquis, they met with several different currents of air, the effect of which was, to give a very sensible shock to the machine, and the direction of the motion seemed to be from the upper part downwards. It appears also that they were in some danger of having the balloon burnt altogether; as the Marquis observed several round holes made by the fire in the lower part of it, which alarmed him considerably, and indeed not without reason. However, the progress of the fire was easily stopped by the application of a wet sponge, and all appearance of danger ceased.

18. Speculations were now entertained as to the possibility of a more convenient method of filling balloons, and instead of feeding a fire as it ascended, to inclose inflammable air at once in the machine; a plan which promised many advantages over the other. The first experiment upon it, was made by two brothers, M. Robert, and M. Charles, a professor of experimental philosophy. A bag composed of lutestring was varnished over with a solution of the elastic gum, called caoutchouc; and was about thirteen English feet in diameter. Many difficulties occurred in filling it with inflammable air; but being at last set at liberty, after having been well filled, it was thirty-five pounds lighter than an equal bulk of common air. It remained in the atmosphere about three quarters of an hour, during which it travelled fifteen miles. Its sudden descent was supposed to have been owing to a rupture, which had taken place when it ascended into the higher regions of the atmosphere.

This experiment, and the successful voyage made by M. Pilatre and the marquis, encouraged the idea of undertaking something of the same kind with a balloon filled with inflammable air. The machine used on this occasion

was formed of gores of silk, covered with a varnish of caoutchouc, of a spherical figure, and measuring twenty-seven feet and a half in diameter. A net was spread over the upper hemisphere, and fastened to a hoop which passed round the middle of the balloon. To this a sort of car was suspended a few feet below the under part of the balloon; and, in order to prevent the bursting of the machine, a valve was placed in it; by opening of which some of the inflammable air might be occasionally let out. The car was of basket work, covered with linen and beautifully ornamented; being eight feet long, four broad, and three and half deep; in weight 130 pounds. Great difficulties again occurred in filling the machine; but these at last being removed, the two adventurers took their seats about two P.M. on the 1st December, 1783. Persons skilled in mathematics were stationed with proper instruments, to calculate the height, velocity, &c. of the balloon. The weight of the whole apparatus, including that of the adventurers, was 604lb. and a half, and the power of ascent when they set out was 20lb. so that the whole difference betwixt the weight of this balloon and an equal bulk of common air, was 624lb. But the weight of the atmosphere displaced by the inflammable gas was calculated to be 771lb. so that there remains 147 for the weight of the latter; and this calculation makes it only five times and a fourth lighter than common air.

19. When the balloon rose, the thermometer stood at 9°. of Fahrenheit, and the barometer at 30.18 inches; and, by means of the power of ascent with which it left the ground, it mounted upwards till the mercury fell to twenty-seven inches, from which they calculated their height to be about 600 yards. Throwing out ballast occasionally as they found the machine descending by the escape of some of the inflammable air, they found it practicable to keep at pretty near the same distance from the earth during the rest of their voyage; the quicksilver fluctuating between 27 and 27.65 inches, and the thermometer between 53°. and 57°. the whole time. They continued in the air an hour and three quarters, and alighted at the distance of twentyseven miles from Paris; having suffered no inconvenience during their voyage, nor experienced any contrary currents of air, as had been felt by M. Pilatre and the Marquis.

20. As the balloon still retained a great quantity of inflammable gas, M. Charles determined to continue the voyage by himself. M. Robert accordingly left the machine, which was now 130 pounds lighter, and arose with such velocity, that in twenty minutes it was almost 9000 feet from the earth, and entirely out of the sight of terrestrial objects. The globe, which had been rather flaccid, soon began to swell, and the inflammable air escaped in great quantity. He now drew the valve to prevent the balloon from bursting; and the inflammable gas, being considerably warmer than the external air, diffused itself all round, and was felt like a warm atmosphere. In ten minutes, however, the thermometer indicated a great variation of temperature: his fingers were benumbed with cold, and he

felt a violent pain in his right ear and jaw, which he ascribed to the expansion of the air in these organs, as well as to the external cold. But the beauty of the prospect which he enjoyed, made amends for these inconveniences. At his departure the sun was set on the vallies; but the height to which M. Charles was got in the atmosphere, rendered him again visible, though only for a short time. He saw, for a few seconds, vapours rising from the vallies and rivers. The clouds seemed to ascend from the earth, and collect one upon the other, still preserving their usual form; only their colour was grey and uniform for want of sufficient light in the atmosphere. By the light of the moon, he perceived that the machine was turning round with him in the air; and he observed that there were contrary currents which brought him back again. He observed also, with surprise, the effects of the wind, and that the streamers of his banners pointed upwards; which, he says, could not be the effect either of his ascent or descent, as he was moving horizontally at the time. At last, recollecting his promise of returning to his friends in half an hour, he pulled the valve, and accelerated his descent. When within 200 feet of the earth, he threw out two or three pounds of ballast, which rendered the balloon again stationary; but, in a little time afterwards, he gently alighted in a field about three miles distant from the place whence he set out; though, by making allowance for all the turuings and windings of the voyage, he supposes that he had gone through nine miles at least. By the calculations made, it appears that he rose at this time not less than 10,500 feet; a height somewhat greater than that of Mount Etna.

21. Many similar ærial voyages were now performed, of which a particular description would be superfluous. But as it had occurred to M. Charles, in his last flight, that there might be a possibility of directing the machine in the atmosphere, this was attempted by M. Jean Pierre Blanchard; who gives an account of the sensations he felt during one of his ærostatic excursions, somewhat different from those of M. Charles; having, in one part of it, found the atmosphere very warm, in another cold; and having once found himself very hungry, and at another time almost overcome by a propensity to sleep. The height to which he arose, as measured by mathematical instruments, was thought to be very little less than 10,000 feet; and he remained in the atmosphere an hour and a quarter.

agitation of his wings, both in ascending, descending, moving sidewise, and even in some measure against the wind: however, this is supposed, with some degree of probability, to have been a mistake, as in no succeeding voyage could the effect of his machinery be perceived.

23. On the 28th of June, 1784, M. Flewrant and Madame Thible, (the first female who ever dared adventure upon these exploits,) ascended at Lyons before the king of Sweden, who then travelled under the name of Count Haga. On their entering the car, (which was 75 feet in height,) they ascended with great celerity, and in four minutes the noise of the multitude was no longer audible. Two minutes afterwards, the eye could not distinguish them. Their greatest altitude was 13,500 feet, (the highest yet reached) and the flag, with its staff of fourteen pounds weight, being thrown out, it was seven minutes descending to the ground. The thermometer had dropt to 43° on Fahrenheit's scale; and the sensation of cold that they felt, was attended by a ringing in the ears. Different currents were found to occupy the strata of the atmosphere, and when passing from one strata to another, the balloon received a sensible undulation. The travellers continued to feed their fire with vine loppings, till, having exhausted their fuel, they descended in a corn field, after remaining in the atmosphere three quarters of an hour. About a fortnight afterwards, a splendid ascent was exhibited from the outer court of Versailles, by command of the French monarch, as a compliment to the king of Sweden. this balloon, the naturalists, Rozier and Proust, undertook the management. On their stepping into the car, it rose in the most rapid manner to the height of 12,520 feet, and appeared to float in a vast congregation of towering white clouds. The thermometer stood at 21°, and flakes of snow fell copiously on the voyagers, while it only rained below. Descending from this chaos of clouds, they were cheered and delighted by the aspect of the rich and populous district, spread out before them in the most lively manner, and finally alighted at the forest of Chantilly, thirty-six miles from the place of their ascent, after an excursion of one hour and five minutes.

Of

24. In August, the Abbé Carnus, professor of philosophy, and M. Lauchet, professor of belles lettres, ascended at Rodez, a town of Guienne in France, to a height of 3920 yards above the level of the town. These aronauts filled one or two bottles with air at their highest elevation, and found that they contained a quarter less air than if filled at the level of the sea, and that the air was much purer.

22. Similar attempts to direct balloons through the atmosphere, were made in 1784, by Messrs. Morveau and Bertrand, at Dijon, who raised 25. Messrs. Charles and Robert, from their themselves with an inflammable air balloon to success in their former experiments, were enthe height, as was thought, of 13,000 feet; pass-couraged to enlarge their balloon to the size of ing through a space of eighteen miles in an hour and twenty-five minutes. M. Morveau had prepared oars for directing the machine through the air; but they were damaged by the wind, so that only two remained serviceable; by working these, however, they were able to produce a sensible effect on the motion of the machine. In a third ærial voyage performed by M. Blanchard, he seemed to produce some effect by the

an oblong spheroid, 46 feet and a third long, and 27 and a half in diameter, made so as to float with its longest part parallel to the horizon. The wings were of the shape of an umbrella without the handle, to the top of which a stick was fastened parallel to the aperture of the umbrella. See Plate I. fig. 2. Five of these were disposed round the car, which was near 17 feet in length. The balloon was filled in

three hours, and, with the addition of 450 lbs. of ballast, remained in æquilibrio with the atmosphere. About noon, on the 19th September 1784, they began to ascend; and having risen to the height of 1400 feet, they perceived some thunder clouds near the horizon, which they took great pains to avoid. From this account, however, it should seem, that they had passed safely through the thunder clouds; as, about forty minutes after three, they heard a loud clap of thunder; and, three minutes after, another much louder; at which time the thermometer sunk from 77 to 59 degrees. The sudden cold, occasioned by the approach of these clouds, condensed the inflammable air, so that the balloon descended very low, and they were obliged to throw out forty pounds of ballast; yet on examining the heat of the air within the balloon, they found it to be 104°, when that of the external atmosphere was only 63. When they had got so high that the mercury in the barometer stood only at 23.94 inches, they found themselves becalmed; so that the machine did not go even at the rate of two feet in a second, though it had before gone at the rate of 24 feet in a second. On this they determined to try the effect of their oars to the utmost; and, by working them for thirty-five minutes, and marking the shadow of the balloon on the ground, they found in that time, that they had described the segment of an ellipsis, whose longest diameter was 6000 feet. After having travelled about 150 miles, they descended, only on account of the approach of night, having still 200 pounds of ballast left.

26. The effect of their wings is described thus:- Far from going against the wind, as is said by some persons to be possible in a certain manner, and some æronauts pretend to have actually done, we only obtained, by means of two oars, a deviation of 22°: it is certain, however, that if we could have used our four oars, we might have deviated about 40° from the direction of the wind; and as our machine would have been capable of carrying seven persons, it would have been easy for five persons to have managed and put in action eight oars, by means of which a deviation of about 80° would have been obtained. We had already observed, (say they) that if we did not deviate more than 22°, it was because the wind carried us at the rate of twenty-four miles an hour; and it is natural to judge, that, if the wind had been twice as strong as it was, we should not have deviated more than one half of what we actually did; and, on the contrary, if the wind had been only half as strong, our deviation would have been proportionably greater.'

27. One of the longest and most remarkable ærial voyages ever performed in France, was undertaken at Paris, in June 1786, by M. Testu, with a balloon twenty-nine feet in diameter, of glazed tiffany, furnished with wings, and inflated with gas. He ascended at four o'clock in the afternoon, the barometer standing at 29.68 inches, and the thermometer at 84°, though the day was cloudy and lowering. The machine had been only filled, but gradually swelled as it became drier and warmer, and acquired its

full distension at the height of 2800 feet; when, to avoid the waste of gas, and the danger of a rupture, M. Testu attempted to lower the balloon by his wings. Not being able to succeed, he thought proper to descend, and alighted in a corn field in the plain of Montmorency, when he was surrounded by the proprietor of the field, and a troop of peasants, who seized him, and insisted on being indemnified for the mischief occasioned by his idle and curious followers. He persuaded them that his wings were broken, and that he and the balloon were entirely at their mercy; when they drew both along, in supposed triumph, by cords fixed to the car, till M. Testu, perceiving that the loss of wings, cloak, &c. had made the balloon much lighter, suddenly cut the string, and left the farmer and his peasants gazing below. He now arose to the region of the clouds, whence he saw small frozen particles floating in the atmosphere, and heard thunder rolling under his feet. As the coolness of the evening advanced, the power of ascension diminished, and he alighted on the ground near the abbey of Royaumont about seven o'clock. He afterwards threw out some ballast, and rose again to a height of 2400 feet, when the thermometer was 66°. He now heard the blast of a horn below, and saw a company of huntsmen in full chase. He immediately opened the valve, and descended between Etouen and Varville; when rejecting his oars, he began to collect some ballast. While he did this, the huntsmen gallopped up to him. He then made another ascent, and passed through a dense body of clouds, awful by the frequent thunders, and flashes of lightning following each other in a rapid and vivid stream, illuminating the whole heavens at every explosion. The thermometer fell to 21°; but at the height of 3000 feet, rose as high as 56°. At this altitude, he floated about till half past nine o'clock, when he witnessed the final setting of the sun; a scene so grand, as to mock the richness of description. After this, he was involved in thick masses of thunder clouds, and lightnings flashing round him on all sides. The thermometer sunk to 21°. Snow and sleet fell copiously; loud peals of thunder rolled around, and seemed to shake the very firmament. This tremendous scene continued three hours, during which time our æronaut remained in the midst of the storm. The balloon was affected by a sort of undulating motion upward and downward, occasioned, as he supposed, by the electric action of the clouds. The lightning was excessively vivid, and the thunder was preceded by a sort of crackling noise. A calm at last succeeding, the stars broke upon his sight as clear as ever, and the sky seemed perfectly serene. He then took some refreshment, and at half-past two o'clock the day began to open upon the world. He staid till he had witnessed the rising of the sun, and afterwards descended to the earth, and alighted near the village of Campremie, sixty-three miles from Paris, having completed a voyage of nearly twelve hours.

28. The first balloon seen in England, was constructed by the ingenious Italian, Count Zambeccari. It was ten feet in diameter, weighed eleven pounds, and consisted of oiled silk, gilt,

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