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by which means it became, not only more beautiful, but less permeable to the gas. It was launched from the Artillery ground, London, on the 25th of November, 1783; and was taken up at Petworth in Sussex, at the distance of fortyeight miles.

29. On the 21st of September, 1784, Vincent Lunardi, an Italian, is said to have made the first ærial ascent in England. His balloon was of oiled silk, striped with blue and red, and thirty-three feet in diameter. There was no valve; the neck, which was in the form of a pear, through which the gas was introduced, being the medium through which it might be emitted. He took with him a dog, a cat, and a pigeon; and after remaining sometime, alighted, about twenty minutes after three, in a meadow in the neighbourhood of Ware, Hertfordshire.

30. Blanchard, who had performed numerous voyages before, on the 16th October ascended with Mr. Sheldon, professor of anatomy to the royal academy, from Chelsea, and after a short voyage of fourteen miles, brought his companion down, and re-ascended to so great an altitude, that he found great difficulty in breathing. The atmosphere at that height was so rare, that a pigeon sent off from the car, found great difficulty in supporting itself, and at length came and settled on the machine, afraid to venture in the boundless ocean which he saw on every side.

31. On the 7th of January, 1785, the same gentleman ascended from Dover, with Dr. Jefferies of America, on the daring exploit of crossing the sea to Calais. The morning was clear and frosty, and a little wind, scarcely perceptible, NNW. The balloon was stationed on the cliff, and at one o'clock, when all things were arranged, M. Blanchard ordered the boat to be pushed off, from the top of that celebrated precipice so finely described by Shakspeare. The balloon being scarcely sufficient to carry two men, (for in fact, Blanchard, though a successful adventurer, had little scientific knowledge as an æronaut,) they were soon obliged to cast out all their ballast, except three bags of sand, weighing in the whole thirty pounds. After this, they rose a little, but moved very slowly, in consequence of the calmness of the atmosphere. In a short time the barometer which on the cliff stood at 29°, 7'. had fallen to 27°, 3′. The weather being fine and warm, they had now a most beautiful view of the south of England. At ten minutes before two o'clock, when they were just in the midst of the strait, twelve miles from either shore, they found the balloon descending, and became alarmed at their situation. They threw out half their remaining ballast, but their descent was still more rapid than before; they then threw out the remainder, but this was insufficient; they next cast out a quantity of books. This caused the balloon again to ascend, but at a quarter past two, finding themselves again descending, they threw out the remainder of their books, and ten minutes after had a most delightful view of the coast of France. Still, however, the balloon was falling, and having no more ballast, they cast out their provisions, cut off the wings of their boat, and parted with every thing VOL I.

that was moveable, even to their only bottle, which in its descent cast out a steam like smoke, accompanied by a rushing noise, and when it struck the water, the balloon felt the shock. All this not stopping the descent of the balloon, they next threw out their anchors and cords, and at last stripped off their clothes, and fastening themselves to certain slings, intended to cut away the boat as their last resource. The balloon, however, began to rise, and they finally descended in safety in the forest of Guiennes, not far from Calais. The magistrates of that town received them with great kindness, and the king presented M. Blanchard with 12,000 livres, and a pension of 1200.

32. It would be tedious to relate all the different ærial voyages that have been performed in this and other countries; but we must not omit the ingenious Mr. Baldwin's excursion from Chester. This gentleman in September, 1785, ascended in Mr. Lunardi's balloon; and after traversing the air in a variety of directions, first alighted in the neighbourhood of Frodsham; then re-ascending, and pursuing his excursion, he finally landed at Rixtonmoss, twenty-five miles from Chester. Mr. Baldwin published the observations he made during this voyage, and gives the following curious particulars of it:-The sensation of ascending, he compares to a strong pressure from the bottom of the car upwards against the soles of his feet. At the distance of what appeared to him seven miles from the earth, though by the barometer, scarcely a mile and a half, he had a grand and most enchanting view of the city of Chester, and its adjacent places, below. The river Dee was of a red colour; the city very diminutive, and entirely blue. The whole seemed a perfect plain, the highest building having no apparent height, but all reduced to the same level, and the whole terrestrial prospect appeared like a coloured map. The perspective appearance of things to him, was very remarkable. The lowest bed of vapour that first appeared as a cloud, was pure white, in detached fleeces, increasing as they rose: they presently coalesced, and formed, as he expresses it, a sea of cotton, tufting here and there by the action of the air in the undisturbed part of the clouds. The whole became an extended white floor of cloud, the upper surface being smooth and even. Above this white floor he observed, at great and unequal distances, a vast assemblage of thunder clouds, each parcel consisting of whole acres in the densest form: he compares their form and appearance to the smoke of pieces of ordnance, which had consolidated as it were into masses of snow, and penetrated through the upper surface or white floor of common clouds, there remaining invisible and at rest. Some clouds had motions in slow and various directions, forming an appearance truly stupendous and majestic.

33. Mr. Baldwin endeavoured to convey some idea of the scene by a sketch, for which, see Plate II. fig. 1. It represents a circular view he had from the car of the balloon, himselt being over the centre of the view, looking down on the white floor of clouds and seeing the city of Chester through an opening, which discovered

the landscape below, limited by surrounding of this kind was connected with the desire to vapour to less than two miles in diameter. The breadth of the outer margin defines his apparent height in the balloon (viz. four miles) above the white floor of clouds. These regions did not feel colder, but rather warmer, than below, and the sun felt hottest when the balloon was stationary. The discharge of a cannon when the balloon was at a considerable height, was distinctly heard; and a second discharge, when at the height of thirty yards, so disturbed him as to oblige him for safety to lay hold firmly of the cords of the balloon. At a considerable height he emptied a pint bottle full of water; and as the air did not oppose a resistance sufficient to break the stream into small drops, it mostly fell down in large ones. The balloon was much affected by the water (a circumstance observed by others,) and at one time was going directly towards the sea. The mouth of the balloon, however, being opened, it descended into an under current blowing from the sea, and Mr. B. at length landed at Bellair Farm, in Rinsley, twelve miles from Chester.

34. The first ærial voyage that was made in Scotland, was performed by Mr. Vincent Lunardi, who, in November and December 1785, ascended twice from Heriot's Hospital-Gardens, Edinburgh. On both these occasions he went entirely out of sight, and the first day of his exhibition being remarkably fine and clear, his balloon, for a long time before it became quite invisible, by the reflection of the sun beams, appeared at first like a full moon, and afterwards like a star of the first magnitude. He alighted safely on that occasion in a field between Cupar and St. Andrews; but in his second voyage he was not so fortunate; for, a strong wind blowing from the west, his balloon was carried in an easterly direction, and when the power of the inflammable air was exhausted, fell into the sea, near the Isle of May, where he was taken up by some fishermen; after having, for a considerable time, experienced the cold bath in his basket: which was prevented from sinking altogether, by the small quantity of inflammable air still remaining in the balloon. After this he repeated his ærial voyages at Glasgow, Kelso, and several other places. Previous to Mr. Lunardi's exhibitions, Mr. James Tytler had greatly excited the public curiosity by undertaking to ascend from Comely Gardens with a rarefied air balloon; but, excepting one morning, that he went up a few hundred yards, in a small basket, without his stove, every other attempt, to make the balloon carry up him and the whole necessary apparatus, proved fruitless. Had he filled his balloon with inflammable, instead of rarefied air, as his skill in chemical operations is undoubted, he would certainly have succeeded, and in that case might have claimed the honour of being the first æronaut in Britain. 35. SECT. II. The attempts to improve the structure of ERONAUTIC machines will now engage our attention; and feeling that we have entered sufficiently into the details of preceding voyages, we shall only occupy our pages in the continuation of this article with such ascents as were nade for scientific purposes. A first attempt

lessen the expence of balloons, by discovering some method of ascending without throwing out ballast, and of descending without losing any of the inflammable air. The balloon of the duke de Chartres, afterwards duke d'Orleans, who ascended with this view from Paris in 1784, was constructed upon somewhat new principles. It was of an oblong form, made to ascend with its longer diameter horizontally, and measured fifty-five feet in length, and twenty-four in breadth. It contained within it a smaller balloon filled with common air; by blowing into which with a pair of bellows, and thus throwing in a considerable quantity of common air, it was supposed that the machine would become sufficiently heavy to descend; especially as, by the inflation of the internal bag, the inflammable air in the external one would be condensed into a smaller space, and thus become specifically heavier. The voyage, however, was attended with such circumstances as rendered it impossible to know what would have been the event of the scheme. The power of ascent, with which they set out, seems to have been very great; as in three minutes after parting with the ground, they were lost in the clouds, and involved in such a dense vapour, that they could see neither the sky nor the earth. In this situation they seemed to be attacked by a whirlwind, which, besides turning the balloon three times round from right to left, shook and beat it so about, that they were rendered incapable of using any of the means proposed for directing their course; and the silk stuff, of which the helm had been composed, was torn away. No scene can be conceived more terrible, than that in which they were now involved. An immense ocean of shapeless clouds rolled upon one another below them, and seemed to prevent any return to the earth, which still continued invisible, while the agitation of the balloon became greater every moment. In this extremity they cut the cords which held the interior balloon, and of consequence it fell down upon the aperture of the tube, that came from the large balloon into the boat, and stopped it up. They were then driven upwards by a gust of wind from below, which carried them to the top of that stormy vapour in which they had been involved. They now saw the sun without a cloud; but the heat of his rays, with the diminished density of the atmosphere, had such an effect on the inflammable air, that the balloon seemed every moment ready to burst. To prevent this, they introduced a stick through the tube, in order to push away the inner balloon from its aperture; but the expansion of the inflammable air pushed it so close, that all attempts of this kind proved ineffectual. It was now, however, become absolutely necessary to give vent to a very considerable quantity of the inflammable air; for which purpose the duke de Chartres himself bored two holes in the balloon, which tore open for the length of seven or eight feet. On this they descended with great rapidity, and would have fallen into a lake, had they not hastily thrown out sixty pounds of ballast, which enabled them just to reach the water's edge.

36. This plan for navigating ærostatic machines

by common air, being thus rendered dubious, another method was suggested: which was to put a small rostatic machine with rarefied air under an inflammable air balloon, but at such a distance that the inflammable air of the latter might be perfectly out of the reach of the fire used for inflating the former; and thus, by increasing or diminishing the fire in the small machine, the absolute weight of the whole would be considerably diminished or augmented. This scheme was unhappily put in execution by the celebrated M. Pilatre de Rozier and M. Romaine. Their inflammable air balloon was about thirty-seven feet in diameter, and the power of the rarefied air one, was equivalent to about sixty pounds. They ascended without any accident; but had not been long in the atmosphere, when the inflammable air balloon was seen to swell very considerably, at the same time that the Eronauts were observed, by telescopes, very anxious to get down, and busied in pulling the valve and opening the appendages to the balloon, in order to facilitate the escape of as much inflammable air as possible. Soon after this the machine took fire, at the height of about three quarters of a mile from the ground. No explosion was heard; and the silk of the balloon seemed to resist the atmosphere for about a minute; after which it collapsed, and descended along with the two unfortunate travellers so rapidly, that both of them were killed. Rozier seemed to have been dead before he came to the ground; but M. Romaine was alive when some persons came up to him, though he expired immediately after. 37. But the most striking improvement that has been attempted in the management of balloons is, the detaching a distinct vehicle for the safety or separate descent of the æronaut. The first invention of this description, now denominated a parachute, (Fr. a guard for falling,) is attributed to Bianchard, who, in one of his excursions from Lisle, about the end of August, 1785, let down from a great height a dog, by means of a basket fastened to a parachute, and the animal reached the ground unhurt. Since that period, the practice and management of the parachute have been carried much farther by other ærial adventurers, and particularly by M. Garnerin, who has repeatedly descended from the region of the clouds by that very slender machine.

When he visited London in 1802, he made two ascents, in the second of which he threw himself from an amazing elevation in his parachute, consisting of thirty-two gores of canvass, forming a complete hemisphere. When the balloon rose, the parachute hung like a curtain from the hoop, and below it was suspended a cylindrical basket, covered with canvass, four feet high and two and a quarter wide. In this basket the æronaut placed himself, and rose from North Audley-street, on the evening of the 2d of September. After hovering five or six minutes in the air, he cut the rope, and precipitated himself to the earth. Before the parachute opened he fell with great velocity, but as soon as it was expanded the descent was gradual: the whole apparatus, however, swung with the aeronaut from one direction to another, like the pendulum

of a clock, and made such tremendous oscillations, that the basket was sometimes thrown in almost an horizontal position, and was borne along before the wind over Mary-le-Bone and Somer's-Town, till it alighted in a field of St. Pancras. M. Garnerin received some severe cuts, bled considerably, and trembled, and was greatly agitated on his release from the basket. He said that the accident had been caused by one of the stays of the parachute having given way.

38. This voyage, and subsequent experiments of the same kind, gave rise to calculations on the rate and danger of the descent with a parachute, When it is first abandoned to the air, we see it fall with great celerity till the increasing velocity meets a resistance in the air equal, or nearly so, to the force of gravitation, after which it descends uniformly; but as this equilibrium is not attained at once, the machine in the first instance shoots beyond the bounds of its terminal velocity, then contracts within its just limits, exciting great alarm both in the æronaut and the spectators; and thus continues for some time, subject to a sort of interior oscillation, alternately accelerating and retarding. If the surface were flat, its motion would be equal to the velocity which a heavy body must acquire in falling through the altitude of a column of air incumbent on that surface, and having the same gravity as the whole apparatus. But a cylinder of air of one foot diameter and height, weighs only of a pound avoirdupoise. Wherefore if the square of the diameter of the parachute be divided by 17, the quotient will give the weight of an atmospheric column of one foot, and the weight of the apparatus being again divided by this quotient, will give the entire altitude of an equiponderant column; the square root of which multiplied by 8, will express the final velocity with which the parachute will strike the surface of the earth: thus, if the diameter of the parachute were 25 feet, then 25×25=625, which, divided by 17=3619. If, then, the parachute and aronaut weighed 3613, the shock would be equal to a fall of one foot; had the weight been twice as great, the fall would have been twice as heavy, &c. the velocity being at least 8/4, or 16 feet a second.

39. The resistance of the air, however, is greater than theory supposes. In the higher regions of the air the parachute descends with a rapidity that is not maintained in a dense atmosphere; and when the momentary inconvenience of rushing through this part of the atmosphere is overcome, the mean descent may be calculated at the rate of 12 feet a second, or a mile in 7 minutes; a rate which will not make the shock at the earth considerable.

40. It being now supposed that balloons might be usefully employed in observing the state of the atmosphere, and what circumstances attended the magnetic and electric actions in the upper regions; as also the proportions of the component parts of air in different altitudes, more or less remote from the earth, Messrs. Robertson and Lhoest made an ærial voyage from Ham burgh about the middle of July, 1803, and rose to so great a height, that the elasticity of the air

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