A E R 



Rozicr anl t"ie marquis d'Aihndca took llicir refpeftive 

 polls in ill- f::ini;ry, and at 54 minutes after one the machine 

 wai abfulutcly abandoned to the clement, and afcendcd 

 calmly and maieftically in the atmofpherc. The aeronauts, 

 hiv'u^ reached" the hcijTht of about 2S0 feet, waved their 

 hats ^o the allonifhed multitude: but they foon rofe too 

 high to be d!ftin!;uilhed, and are thought to have foarcd to 

 an elevation of above 3000 feet. Tlicy were at firft driven 

 by a north-weft wind horizontally over the ri\er Seine and 

 over Paris, taking care to clear the ileeples and high build- 

 ings by increafing the fire ; and in rifmg met with a current 

 of air, which carried them fouthward. Having padcd the 

 Boiilevard, and defifting from fupplying the fire with fuel, 

 thty defcended vei-y gently in a field beyond the new Bou- 

 levard, about 9000 yards diftant from th.c palace de la 

 Misettc. They were in the air about 25 minutes. The 

 weight of the whole apparatus, including that of the two 

 travellers, was between 1600 and 1700 pounds. 



Notwithflanding the rapid progrefs of aeroftation in 

 France, we have no authentic accoimt of any aeroftatic ex- 

 periments performed in other countries till about the clofe 

 of the year 1783. The firft experiment of this kind, p'lb- 

 liclv exhibited in our own country, was performed in London 

 on the 25th of Norember, by count Zainbeccari, an inge- 

 nious Italian, with a balloon of oil filk, 10 feet in diameter, 

 and weighing 1 1 pounds. It was gilt, in order to render it 

 more beautiful and more impermeable to the inflammable air. 

 This balloon, thrse-fourths of which were filled with in- 

 flammable air, was launched from the Artilleiy -ground, in 

 the prefence of a vaft concourfe of fpeftators, at one o'clock 

 in the afternoon, and at half paft three was taken up near 

 Petwoith, in SufTex, 48 miles diftant from London ; fo 

 that it travelled at the rate of near 20 miles an hour. Its 

 defcent was occafioned by a rent, which mull have been the 

 effect of the rarefaction of the inflammable air, when the 

 balloon afcended to the rarer part of the atmofphere. 



The Parifian philofophers having concerted and executed 

 flie firft aerial voyage with a balloon inflated by heated air, 

 determined to attempt a fimilar voyage with a balloon filled 

 with inflammable air, which feemed to be preferable to 

 dilated air in eveiy refpeft, the expence attending it ex- 

 cepted. A fnbfcription was opened to defray the charges, 

 which were eftimated at about ten thoufand livres ; and the 

 balloon was conftrufted by Meflrs. Roberts, of gores of 

 filk, varniflied with a folution of elaftic gum. Its form 

 was fpherical, and it meafured 27^ feet in diameter. The 

 upper hemifphere was covered by a net, which was fattened 

 to the hoop encircling its middle, and called its equator. To 

 this equator was fufpended by ropes a car or boat, covered 

 with painted linen and beautifully ornamented, which 

 fwung a few feet below the balloon. In order to prevent 

 the burfting of the machine by the expanfion of the inflam- 

 mable air in a rarefied medium, it was furniflied with a valve, 

 which might be opened by means of a ftring annexed to it, 

 for the difcharge of part of the internal air without ad- 

 mitting the external to enter. To this balloon was likewife 

 annexed a long pipe through which it was filled. The 

 apparatus for filling it confifted of feveral can<s placed 

 round a large tub of water, each of which had a long tin 

 tube, terminating under a veffel or funnel, that was inver- 

 ted into the water of the tub. A tube proceeding from 

 this funnel, communicated with the balloon, which ftood 

 jnfl over it. Iron filings and diluted vitriolic acid were put 

 into the cafks ; and the inflammable air, produced from 

 thefe materials, paffed through the tin tubes, through the 

 water of the tub, and through the funnel of the balloon. 

 The car was ballaftcd with fand-bags j fo that by letting 



A E R 



fome of the air efcape tliroiijjh the valve tliey might dc- 

 fcend, and by difcharging (ome of their ballaft afcend. 

 The fpecific gravity of the inflammable air, with which the 

 balloon was filled, was to that of common air nearly as i to 

 5^, and the balloon's power of afcenfion, when filled for 

 the experiment and wnen aftually afcending, was twenty 

 pounds. The weight of the balloon and cf its various 

 appendages was 6045 pounds, and therefore the weight 

 fiiitained by the inflammable air was 6244 pounds : and if 

 from the weight of the common air difplaced, which was 

 found to be 771= pounds, the former be fubtrafled, there 

 will remain 147 pounds for -'ic real weight of the inflam- 

 mable air contained in the balloon. 



The I ft of December was fixed upon for the difplay of 

 this grand experiment ; and every precaution was made for 

 condufting it with advantage. The garden of the ThuiUie- 

 ries was the fcene of operation ; and it was crowded and 

 encompafled with an innumerable multitude of obfcrvers. 

 Signals were CTiven by the firing of cannon, waving of pen- 

 dants, &c. A fmall Montgo!Ji<r was launched for fticv.ing 

 the direftion of the wind, and f(jr the amuiement of the 

 people, previoufiy to the general difplay. At three quarters 

 after one o'clock, M. Charles and one of the Roberts, hav- 

 ing feated thenifelves in the boat attached to the balloon, 

 and furnifiied with proper inftruments, provifions, and. 

 cloathing, left the ground, and aicended with a moderately 

 accelerated velocity to the height of about 600 yards ; the 

 furiounding multitude ftanding filent with fear and amaze- 

 ment. At this height the aerial navigators made fignals of 

 their fafety. When they went up, the themiometer, ac- 

 cording to Fahrenheit's fcale, ftood at 59° ; and the baro- 

 meter at 30, 18 inches. At the height to which they 

 afcended the barometer ftood at 27 inches, whence they 

 deduced their elevation to be nearly 600 yards. During 

 the reft of the voyage the quickfilver in the barometer was 

 generally between 27 and 27, 6^ inches, rifing and falling as 

 part of the ballaft was thrown out or fome of the inflam- 

 mable air efcaped from the balloon. The thenuometer ge- 

 nerally ftood between 53 and 57°. Soon after their al'cent, 

 they remained ftationaiy for lome time ; they then moved 

 horizontally in the direction of N. N. W. and having croff- 

 ed the Seine, and paiTcd over feveral towns and villages, to 

 the great allonifliment of the inhabitants, they defcended in 

 a field about 27 miles diftant from Paris at a quarter paft 

 three o'clock ; fo that they had travelled at the rate of 

 about fifteen miles an hour, without feeling the Icaft incon- 

 venience. The balloon ftill containing a confiderable quan- 

 tity of inflammable air, M. Charles re-afcended alone. In 

 ten minutes he thought himfelf at the elevation of about 

 1500 toifes. The globe, being now in a rarefied medium, 

 fwelled confiderably ; but when fome of the inflammable air 

 was difcharged, it rofe ftill higher. The barometer, which 

 at his departure ftood at 28 inches four lines, had now 

 fallen to 18 inches ten lines. The thermometer, from about 

 47° of Fahrenheit's fcale, had funk to 21°. From thefe 

 data the elevation of the globe was eftimated at 1524 toifes, 

 or about 3,100 yards. M. d* Meunier fuppofes that he 

 afcended to the height of at leaft 3500 yards. He con- 

 tinued in the air about 33 minutes, and by occafionally 

 pulling the ftring of the upper valve, and thus letting out 

 the gas, he defcended about three miles from the place of 

 his alcent. All the inconvenience he experienced in his 

 elevation was a dr)- fliarp cold, with a pain in one of his 

 ears and a part of his face, which he afcribed to the dilata- 

 tion of the internal air. The fmall balloon, launched by 

 M. Montgolfier, was found to have moved in a direftion 

 oppofite to that of the aeronauts ; whence it is inferred, 



that 



