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low. From some experiments they con- the boat, he had affixed a number of bladcluded, that they were able by the use of ders, for the purpose of rendering his gallery two oars to deviate from the direction of the buoyant, in case of a disaster at sea. The wind about 22o. But this experiment re height to which he ascended at one time quires repetition, in order to ascertain with was such, that by the intense cold his ink accuracy the effect here ascribed to oars. was frozen, and the mercury sunk into the The second aerial voyage in England was
ball of the thermometer. He himself was performed by Mr. Blanchard and Mr. Shel- sick, and he felt a strong impression on the don, professor of anatomy to the Royal tympanum of his ears. At his utmost ele. Academy, the first Englishman who ascended vation he thought himself stationary; but on with an aerostatic machine. This experi- discharging some gas he descended to a very ment was performed at Chelsea on the 16th rough current of air blowing to the north. of October. The wings used on this occa
He then entered a dense cloud, and expe- ! sion seemed to have produced no deviation rienced strong blasts of winds, with thunder in the machine's track from the direction of and lightning, which brought him with rapithe wind. Mr. Blanchard, having landed dity towards the surface of the water. The his friend about the distance of 14 miles from water soon entered his car; the force of the Chelsea, proceeded alone with different cur- wind plunged him into the ocean, and it was rents, and ascended so high as to experience with difficulty that he put on his cork jacket. great difficulty of breathing: a pigeon also, The bladders which he had prepared were which flew away from the boat, laboured now found of great use. The water, added for some time with its wings, in order to sus to his own weight, served as ballast; and the tain itself in the rarefied air, and after wan balloon maintaining its poise, answered the dering for a good while, returned and rested purpose of a sail, by means of which, and a on one side of the boat. Mr. Blanchard snatch-block to his car, he moved before the perceiving the sea before him, descended wind as regularly as a sailing-boat. He was near Rumsey, about 75 miles from London, at length overtaken by some vessels that having travelled at the rate of nearly 20 were crowding sail after him, and conveyed miles an hour.
to Dunleary with the balloon. On the 22d On the 12th of October, Mr. Sadler, of of July, Major Money, who ascended at Oxford, made a voyage of 14 miles from that Norwich, was driven out to sea, and after place in 17 minutes, with an inflammable air having been blown about for about two balloon of his own contrivance and construc- hours, he dropped into the water. After tion. The fate of M. P. de Rozier, the first much exertion for preserving his life, and aerial navigator, and of his companion M. when he was almost despairing of relief, he Romain, has been much lamented. They was taken up by a revenne cutter in a state ascended at Boulogne on the 15th of June, of extreme weakness : having been struggling with an intention of crossing the channel to to keep himself above water for about seven England. Their machine consisted of a hours. spherical balloon, 37 feet in diameter, filled The longest voyage that had been hitherto with inflammable air, and under this balloon made was performed by Mr. Blanchard, towas suspended a small Montgolfier, or fire wards the end of August. He ascended at balloon, ten feet in diameter. This Mont- Lisle, accompanied by the Chevalier de golfier was designed for rarefying the atmos- L'Epinard, and traversed a distance of 300 pherie air, and thus diminishing the specific miles before they descended. On this, as gravity of the whole apparatus. For the well as on other occasions, Mr. Blanchard first twenty minutes they seemed to pursue made trial of a parachute, in the form of a the proper course; but the balloon seemed large umbrella,which he contrived for breakto be much inflated, and the aeronauts ap- in bis fall in case of any accident. With peared anxious to descend. Soon, however, this machine he let down a dog, which came when they were at the height of about three to the ground gently, and unhurt. On the quarters of a mile, the whole apparatus was 8th of September Mr. Baldwin ascended in flames, and the unfortunate adventurers from the city of Chester, and performed an fell to the ground, and were killed on the aerial voyage of 25 miles in two hours and a spot.
quarter. His greatest elevation was about a · On the 19th of July Mr. Crosbie ascended mile and a half, and he supposes that the at Dublin, with a view of crossing the chan- velocity of his motion was sometimes at the nel to England. To a wicker basket of a rate of 20 miles an hour. He has published cirenlar form, which he had snbstituted for a circumstantial account of his voyage, de
scribed the appearances of the clouds as he descending with a machine called a parapassed through them, and annexed a variety chute, was performed by Mr. Garnerin on of observations relating to aerostation. the 21st of September, 1802. He ascended
It would be tedious to recount the aerial from St. George's parade, North Audley expeditions that were performed in various Street, and descended safe into a field near parts of our own country, as well as on the the small-pox hospital, at Pancras. The continent, in the whole course of the year balloon was of the usual sort, viz. of oiled 1785: more especially as they have afforded silk, with a net, from which ropes proceeded, us no experiment or discovery of any pecu- which terminated in, or were joined to a liar importance. The most persevering single rope at a few feet below the balloon. aerial navigator has been Mr. Blanchard. To this rope the parachute was fastened in In August, 1788, he ascended at Brunswick the following manner. The reader may for the thirty-second time. Within two easily form to himself an idea of this parayears from the first discovery of this art of chute, by imagining a large umbrella of cannavigating the atmosphere, more than forty vas, of about 30 feet in diameter, but destidifferent persons performed the experiment tute of the ribs and handle. Several ropes, without any material injury; and it may be of about 30 feet in length, which proceeded justly questioned, says Mr. Cavallo, whether from the edge of the parachute, terminated the first forty persons who trusted them in a common joining, from which shorter selves to the sea in boats escaped so safely. ropes proceeded, to the extremities of which The catastrophe that befel Rozier, and the a circular basket was fastened, and in this unpleasant circumstances that have hap- basket Mr. Garnerin placed himself. The pened to some of the aeronauts in onr own single rope passed through a hole in the cen. country, have been owing not so much to tre of the parachute, also through certain the principle of the art, as to want of judg- tin tubes, which were placed one after the ment, or imprudent management in the con- other in the place of the handle or stick of duct of it.
an umbrella, and was lastly fastened to the Omitting the various uninteresting, though basket; so that when the balloon was in the not very numerous aerial voyages undertaken air, by cutting the end of the rope next to in various parts of the world, during the 17 the basket, the parachute, with the basket, years subsequent to the above-mentioned would be separated from the balloon, and, dreadful accident of Pilatre de Rozier and in falling downwards, would be naturally Mr. Romain, we shall only add the account opened by the resistance of the air. The of two aerostatic experiments lately per use of the tin tubles was to let the rope slip formed in England by Mr. Garnerin, a off with greater certainty, and to prevent French aeronaut. The first of these is re- its being entangled with any of the other markable for the very great velocity of its ropes, as also to keep the parachute at a dismotion; the second for the exhibition of a tance from the basket. The balloon began mode of leaving the balloon, and of descend- to be filled about two o'clock. There were ing with safety to the ground. On the 30th 36 casks, filled with irou filings, and diluted of June, 1802, the wind being strong, though sulphuric acid, for the production of the not impetuous, Mr. Garnerin and another hydrogen gas. These communicated with gentleman ascended with an inflammable three other casks, or general receivers, to air, or liydrogen gas balloon, from Ranelagh each of which was fixed a tube that emptied gardens, on the south-west of London, be- itself into the main tube attached to the tween four and five o'clock in the afternoon; balloon. At six, the balloon being quite and in exactly three qnarters of an hour full of gas, and the parachute, &c. being atthey descended near the sea, at the dis- tached to it, Mr. Garnerin placed himself in tance of four miles from Colchester. The the basket, and ascended majestically amidst distance of that place from Ranelagh is 60 the acclamations of innumerable spectators. miles; therefore they travelled at the asto. The weather was the clearest and pleasantnishing rate of 80 miles per hour. It seems est imaginable; the wind was gentle, and that the balloon had power enongh to keep about west by south ; in consequence of them up four or five hours longer, in which which Mr. Garnerin went in the direction time they might have gone safely to the con- of nearly east by north. In about eight mitinent; but prudence induced them to de- nutes the balloon and parachute had ascendscend when they discovered the sea not fared to an immense height, and Mr. Garnerin, off. The singular experiment of ascending in the basket, could scarcely be perceived. into the atmosphere with a balloon, and of While every spectator was contemplating the
grand sight before them, Mr: Garnierin cut using one pound of each to every gallon of the rope, and in an instant he was separated water; and when the cloth is quite dry, to from the balloon, trusting his safety to the paint it over with some earthy colour, and parachute. At first, viz. before the para- strong size or glue. It may be also varnished chute opened, he fell with great velocity; over when perfectly dry, with some stiff, but as soon as the parachute was expanded, oily varnish, or simple drying linseed oil, which took place a few moments after, the which would dry before it penetrates quite descent became very gentle and gradual. through the cloth. The pieces of which an A remarkable circumstance was observed; hydrogen gas balloon is to be formed must namely, that the parachute, with the appen- be cut of a proper size, according to the dage of cords and basket, soon began to vi- proposed dimensions of it, when the varnish brate like the pendulum of a clock, and the is sufficiently dry. The pieces that comvibrations were so great, that more than pose the surface of the balloon are like those once the parachute, and the basket with Mr. gores that form the superficies of a globe ; Garnerin, seemed to be on the same level, and the best method of cutting them is to or quite horizontal: however, the extent of describe a pattern of wood or stiff card-pathe vibrations diminished as he descended. per, and to cut the silk or stuff upon it. To On coming to the earth, Mr. Garnerin ex the upper part of the balloon there must be perienced some pretty strong shocks; but adapted a valye, opening inward, to which he soon recovered bis spirits, and remained is annexed a string passing through a hole without any material hurt. As soon as the made in a small round piece of wood, which parachute was separated from the balloon, is fastened to the lowest part of the balloon, the latter ascended with great rapidity, and, opposite to the valve, to the boat below it; being of an oval form, turned itself with its so that the aeronaut may open it as occasion longer axis into an horizontal position. requires, and let the hydrogen gas out of the
We now come to the practice of the art. balloon. To the lower part of the balloon The shape of the balloon is one of the first are fixed two pipes of the same stuff with objects of consideration. As a sphere ad- the covering, six inches in diameter for a mits the greatest capacity under the least balloon of 30 feet, and much larger for balsurface, the spherical figure, or that which loons of greater size, and long enough to approaches nearest to it, has been generally reach the boat. These pipes are the aperpreferred. However, since bodies of this tures through which the hydrogen gas is inform oppose a greater surface to the air, and troduced into the balloon. The boat may consequently a greater obstruction to the be made of wicker work, and covered with action of the oar or wings than those of some leather, well painted or varnished over. The other form, and therefore cannot be so well best method of suspending it is by means guided in a calm, or in a course different of ropes, proceeding from the net which from the direction of the wind, it has been goes over the balloon. This net should be proposed to construct balloons of a conical formed to the shape of the balloon, and fall or oblong figure, and to make them proceed down to the middle of it, and have various with their narrow end forward. Next to cords proceeding from it to the circmnthe shape, it is necessary to consider the ference of a circle, about two feet below stuff that is most proper for forming the en- the balloon; and from that circle other ropes velope of the inflammable or rarefied air. should go to the edge of the boat. This Silk stuff, especially that which is called circle may be made of wood, or of several lutestring, properly varnished, has been most pieces of slender cane bound together, The commonly used for hydrogen gas balloons : meshes of the net may be small at top, and common linen, lined within and without against which part of the balloon the hydrowith paper, varnished, for those of rarefied gen gas exerts the greatest force, and inair. Varnished paper, or gold beater's skin, .crease in size as they recede from the top. will answer the purpose for making smali A hoop has been sometimes put round the hydrogen gas balloons; and the small rare- middle of the balloon for fastening the fied air balloons may be made of paper, net. This is not absolutely necessary; but without any varnish or other preparation. when used, it is best made of pieces of cane The stuff for large balloons of both kinds re bound together, and covered with leather. quires some previous preparation. The best When the balloon and its appendages are mode of preparing the cloth for a machine constructed, the next object of importance upon Montgolfier's principle, is first to soak is to procure proper materials for filling it. it is a solution of sal-ammoniac and size, Hydrogen gas for balloons may be obtainey
in several ways: but the best methods are silken tubes are fastened round the tin ones ; by applying acids to certain metals; by ex- the iron tilings are to be put into the casks, posing animal, vegetable, and some mineral then the water, and lastly the sulphuric substances, in a close vessel, to a strong fire; acid. The balloon will speedily be inflator by transmitting the vapour of certain ed by the gas, and support itself without Auids through red-hot tubes. In the first of the aid of the rope GH. As the filling adthese methods, iron, zinc, and sulphuric acid vances, a net is adjusted about it, the cords are the materials most commonly used. The proceeding from the net are fastened to the acid must be diluted with five or six parts hoop MN; the boat IK is suspended from of water. Iron may be expected to yield the hoop, and whatever is wanted for the in the common way about 1700 times its voyage is deposited in the boat. When the own bulk of gas; or 4, ounces of iron, the balloon is sufficiently full, the silken tnbes like weight of sulphuric acid, and 224 ounces are separated from the tin tubes, their exof water, will produce one cubic foot of hy- tremities are tied, and they are placed in drogen gas; 6 ounces of zinc, an equal the boat. When the aeronants are seated weight of acid, and 30 ounces of water, are in the boat, the ropes that held the balloon necessary for producing the same quantity. down are slipped off, and the machine asIt is more proper to use the turnings or cends in the air as in figure 2. In figure 3, ehippings of great pieces of iron, as of can. is a representation of a part of Mr. Garnerin's non, &c. than the filings of that metal, be- balloon in its ascent, to which is attached cause the heat attending the effervescence the parachute in its contracted state, and will be diminished, and the diluted acid will below is the car. Figure 4 shews the man. pass more readily through the interstices of ner in which Mr. Garnerin descended in the the turnings, when they are heaped together, car by means of the expanded parachute, than through the filings, which stick closer to after he had detached it from the balloon. one another. The weight of the hydrogen In figure 5 is represented an apparatus, as gas thus obtained by means of sulphuric acid, described by Mr. Cavallo, for filling balloons is, in the common way of procuring it, gene- of the size of two or three feet in diameter rally one-seventh part of the weight of com with hydrogen gas, after passing it through mon air; and with the necessary precau
A is a bottle with the ingredients; tions for philosophical experiments, less than BCD a tube fastened in the neck at B, and one-tenth of the weight of common air. We passing through C, the cork of the other shall conclude this article with a description bottle, in which there is a hole made to reof some figures explanatory of the subject. ceive the tube, and to this the balloon is Figure 1 (plate Aerostation) represents a tied. Thus the hydrogen gas, coming out balloon, DF, suspended by means of the of the tube D, will pass first through the poles G and H, and the cord, for the pur water of the bottle E, and then into the balpose of being filled with gas. It is kept steady loon. Two small casks may be used instead and held down whilst filling by ropes, which of the bottles A and E. are readily disengaged. A, A, are two tubs, ÆRVA, in botany, a genus of the Mona. about three feet in diameter, and two feet delphia Decandria class and order. The deep, inverted in larger tubs, B, B, full of flowers are polyganous; the calyx five-leaved water. At the bottom of each of the in- and patent: the stamina are five; the pistilverted tubs there is a hole, to which is in- lum is a globulous ovary, having a filiform serted a tin tube; to these the silken tubes style, terminated by a bifid stigma : the fruit of the balloon are tied. Each of the tubs, is an oblong, single-seeded capsule, encomB, is surrounded by several strong casks, so passed by a calyx: there is but one species, regulated in number and capacity, as to be viz. the Æ. ægyptiaca, or tomentosa, which less than half full when the materials are grows on the sandy calcareous soil of Arabia. equally distributed. In the top of these ASCHYNOMENE, a word from the casks are two holes ; to one of which is Greek, signifying to be ashamed, becanse it adapted a tin tube, formed so as to pass retreats from the touch: bastard sensitive over the edge of the tub B, and throngh the plant, in botany, a genus of the Diadelphia water, and to terminate with its aperture Decandria class and order, and of the natural under the inverted tub A. The other hole, order of Papilio Naceæ, of which there are which serves for supplying the cask with 12 species found native in the East Indies, materials, is stopped with a wooden plug and cultivated in other hot countries. One When the balloon is to be filled, the com- of the species may be treated as hemp, and mon air is first to'be expelled, then the is used for the same purposes.
AESCULUS, in botany, a genus of the ing. The sediment, after infusion, loses its Heptandria Monogynia class and order, of bitter taste, and becomes good food for the natural order of Trihilatæ. There are fowls when mixed with bran. The Edinthree species : the first, or common horse burgh College have admitted the horsechestnut, was brought from the northern chestnut into their Pharmacopæia of 1783, parts of Asia into Europe about the year on the recommendation of Dr. Gardiner, 1550, and sent to Vienna about the year who says, that three or four grains of the 1558. From Vienna it was conveyed 10 powder snuffed up the nostrils in the eveFrance and Italy; but it came to us from ning, operate next morning as an excellent the Levant. It is distinguished by the beau- sternutatory, and thereby proves very betiful parabolic form of its branches, the dis- neficial in obstinate inflammations of the position and structure of its digitate leaves, eyes. A patent was granted, in 1796, to and by the pyramidal bunches of its white Lord W. Murray, for his discovery of a flowers, variegated near the centre with yel- method of extracting starch from horselow or red. Although this tree is now less chestnuts. in esteem for avenues and walks than it for The second species, or yellow-flowered merly was, on account of the early decay of horse-chestnut, is a native of North Caroits leaves, it affords an excellent shade ; audlina, was cultivated with us in 1764, and the spikes of flowers which appear in May, flowers in May and June. with the intermixture of large leaves, exhibit The third species, or scarlet horse-chest. a noble appearance. The most eligible situa- nut, rises to the height of twenty feet, tion for these trees is in lawns and parks, without much extending its bravches; its where they may be planted singly, and where bark is smooth, and the leaves, which are their fruit will be serviceable to the deer, opposite, on long, red petioles, are of a who are fond of it. This tree is of quick light green. growth; and in a few years it will afford a The common horse-chestnut is propagood shade in summer, and yield plenty of gated by sowing the nuts, after preserving flowers. Trees, raised from nuts, have in 12 them in sand during the winter : but the or 14 years become large enough to shade scarlet is propagated by grafting it upon two or three chairs with their branches, stocks of the common horse-chestnut. which in the season are covered with flowers. ÆTHUSA, in botany, a genus of the PenBut the trees are of short duration, and the tandria Digynia class and order, and belong. Food is of little value. It serves, however, ing to the natural order of Umbellatæ or Umfor water-pipes, turner's ware, and fuel: and belliferæ : the calyx is an universal spreading for these uses it is worth the charge of plant- umbel, and the partial is also spreading, ing, and should be felled in November or but small; having no universal involucre, December. The horse-chesnut has been and the partiul one placed on the outside, employed in France and Switzerland for the and consisting only of three very long, linear, purpose of bleaching yarn; and it is recom- pendulous leaflets, and the proper perianmended in the Memoirs of the Society of thium scarcely observable: the universal Berne, Vol. II. part 2, as capable of exten- corolla is nearly uniform, with all the flossive use in whitening not only flax and hemp, cules fertile, and the partial has the petals but silk and wool. It contains an astringent bent in, heart-shaped, and unequal : the saponaceous juice, which is obtained by stamina are simple tilaments, with roundish peeling the nuts, and grinding or rasping anthers; the pistillum is an inferior germ, and them. 'l'hey are then mixed with hot rain the styles are reflex, with obtuse stigmas : or running water, in the proportion of 20 it has no pericarpium, and the fruit is roundnuts to 10 or 12 quarts of water. Wove ish, streaked and bipartile: the seeds are caps and stockings were milled in this water, two, roundish, streaked, except on a third and took the dye extremely well; and suc part of the surface, which is plain. There cessful trials were made of it in fulling stuffs are four species, the principal is Æ. cyna. and cloths. Linen washed in this water pium, common fool's parsley, or lesser hemtakes a pleasing light sky-blue colour; and lock, which is a common weed in fields and the filaments of hemp, steeped in it some kitchen-gardens, and in a slight degree poidays, were easily separated. The author
It is easily distinguished when in of the memoir, above referred to, imagines, flower, in July and August, from true parthat if the meal of the chestnuts could be sley and chervil, by the three narrow penmade into cakes or balls, it would answer dent leaflets of the involucre, placed on the the purposes of soap, in washing and full- outer part only of the umbel, and by its be