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U>.( I efn propoftd for navigating tbroiij^li the air, fome 

 have haJ recoirfe to artificial wings ; which, being con- 

 ftnirtcJ like thole of birtls and annexed to tlie human 

 bodv. mifht bear it up, ami by tlicir motion, prodiiccd 

 either by mechanical fprings, or miifcular exertion, effett 

 it< progrcfs in anv dircAion at plealurc. This is one of the 

 methods of arlillcial flying Inggelled by bifliop Wilkms, in 

 the feventh chapter of liis Uedaliis. or Trcatife on Mecha- 

 nical Motions; but the fuccefs of it i.rdoubtfu!, and expe- 

 riments made in this way have been few and unlalisfackoy. 

 Borelli (DeMotu Aniinalinm, cap. 22. prop. 193 and 204, 

 p. !</) and 20S, ed. 1710), having compared the power of 

 the miifeles which act on the wings of a bird with that of 

 the mufcics of the brcaft and arms of a man, tinds the latter 

 altogether infufficieiit to produce, by means of any wings, 

 that'^motion a;iainil the air, v.hich is ncccfl'aiy to railc a man 

 in the atmofpherc. 



Othei-s, with greater probability of fuccefs, have pro- 

 pofcd to attach the human body to fomc mafs, which being 

 lighter than air, might raife itfelf and the annexed weight 

 into the regions of that element. This method has adually 

 fucccedcd ; though Borelli {nil fiipra), as well as Leibnitz, 

 denied the pofTibility of a man's flying by any of the means 

 with which tiiey were acquainted. 



It is necdlefs to recite any of the accoimts relating to 

 this fubjeft, which have been tranfmitted to us by the 

 ancients. Moft, if not all of them, are fabulous. An 

 ingenious writer, in a work cited at the clofe of this article, 

 has given us the refult of his enquiries into the records ot 

 antiquity ; and he informs us, that the earlicll account of 

 any thing relating to flying, which has the appearance of 

 authenticity, is that of the wooden pigeon, conftruaed by 

 Archytas in the fourth century, before the Chriftian sra, 

 and of which Aulus Gelhus (Nodles Attics, lib. x. cap. 1 2. ) 

 relates, that it could fly by means of mechanical powers, 

 and by an intlofed fpirit. Thii fpiiit, or aura, our author 

 apprehends, was nothing more than a fort of animation, 

 which the machine appeared to be poflefTed of, in confc- 

 quence of its extraordinary mechanifm. Aeroftation was, 

 therefore, a fubjeft either altogether unknown, or veiy 

 imperfeftly underllood among the ancients ; unlcfs we fup- 

 pole it to be one of thofe arts, of which the records are 

 loll. In later times, the fchemes which have been propofed 

 hv ingenious men feem to have terminated in fpeculation. 

 The reader will find a brief account of fome of them under 

 the articles Atmosphere and Artificial Flying, and a 

 more coniprehenfive hiftory of the projefts and atchieve- 

 ments of different pcrfons, in the work cited below. Upon 

 the whole it appears, that the art of traverfing the air is an 

 invention of our own time ; and the whole hillory of it is 

 comprehended within a veiy ftiort period. 



Soon after Mr. Cavendifh's difcovery of the fpecific gra- 

 vity of inflammable air, it occurred to the ingenious Dr. 

 Black of Edinburgh, that if a bladder, fuihciently hght 

 and thin, were filled with this air, it would form a mafs 

 lighter than the fame bulk of atmofpheric air, and rife 

 in it. This thought was fuggefted in his leAures in 1767 

 or l';"68 ; and he propofed, by means of the allantois of a 

 calf, to try the experiment. Other employments, how- 

 ever, prevented the execution of his defign. The poflibi- 

 lity of conftruAing a veffel, which, when filled with inflam- 

 mable air, would alcend in the atmofphere, had occurred 

 alfo to Mr. CavaUo about the fame time ; and to him 

 belongs the honour of having firfl; made experiments on 

 this fubjtft, in the beginning of the year 1782, of which 

 an account was read to the Royal Society, on the 20th of 



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June in that year. He tried bladders ; but the thinneR of 

 thife, however fcraped and cleaned, were too heavy. In 

 ufing China paper, he found that the inilanimable air pafleJ 

 througli its pores, like water through a ficvc ; and having 

 failed of fnccefi by blowing this air into a thiuk folution of 

 gum, thick varnilhes, and oil paint, he was under a necef- 

 lity of being falislied with foap-balls, which, being inflated 

 with inflammable air, by dipping the end of a Imall glafs 

 tube, connected with a bhidder containing the air, into a 

 thick folution of foap, and gently coniprcifing the blad- 

 der, afceuded rapidly in the atmofphere ; and thefe were 

 the firll fort of inflammable air-balloons that were ever 

 made. 



For balloons formed on a larger fcale, and on the prin- 

 ciple of rarefied air, we muft direct our attention to France ; 

 where the two brotliers, Stephen and Jolepli Montgolfier, 

 paper-maiiufaAurers at Annonay, about 36 miles from 

 Lyons, dillinguilhed themfelves by exhibiting the firll of 

 thofe aeroftatic machines, which have fince excited fo much 

 attention and allonifliinent. The firll idea of fuch a ma- 

 chine was fuggefted to them by the natural afcent of the 

 fmoke and clouds in the atmofphere ; and the firll experi- 

 ment was made at Avignon by Stephen, the eldell of the 

 two brothers, towards the middle of November, 1782. 

 Having prepared a bag of fine filk, in the fhape of a pand- 

 Iclcpipedon, and in capacity about forty cubic feet, he 

 apphed to its aperture burning paper, which rarefied tlie 

 air, and thus formed a kind of cloud in the bag ; and when 

 it became fufficiently expanded, it afcended rapidly to the 

 cieling. Soon afterwards the experiment was repeated by 

 the two brothers at Annonay, in the open air, when the 

 machine afcended to the height of about feventy feet. 

 Encouraged by their fuccefs, they conftrudled a machine, 

 the capacity of which was about 6jo cubic feet ; which, 

 iu the experiment, broke the ropes that confined it, and 

 after afcending rapidly to the height of about 600 feet, 

 fell on the adjoining ground. With another machine, 35 

 feet in diameter, they repeated the experiment in April, 

 1783 ; when breaking loole from its confinement, it rofe to 

 the height of above 1000 feet, and being carried by the 

 wind, it fell at the diftance of about three quarters of a 

 mile from the place where it afcended. The capacity of 

 this machine was equal to about 23,430 cubic feet; and 

 when inflated, it meafured 117 Englilh feet in circumfe- 

 rence. The covering of it was formed of hnen, lined with 

 paper ; its fliape was nearly fpherical ; and its aperture was 

 fixed to a wooden frame about 16 feet in furface. When 

 filled with vapour, which was conjeftured to be about half 

 as heavy as common air, it was capable of lifting up about 

 490 pounds, befides its own weight, which, together with 

 that of the wooden frame, was equal to 500 pounds. 

 With this machine the next experiment was performed at 

 Annonay, on the 5th of June, 1783, before a great mul- 

 titude ot fpeclators. The flaccid bag was fufpended on a 

 pole 35 feet high ; ftraw and chopped wool were burnt 

 under the opening at the bottom ; the vapour, or rather 

 fmoke, foon inflated the bag, fo as to diftend it in all its 

 parts ; and this immenfe mals afcended in the air with fuch 

 a velocity, that in lefs than 10 minutes it reached the 

 height of about 6000 feet. A breeze carried it in an hori- 

 zontal direftion to the dillance of 7668 feet ; and it then 

 fell gently on the ground. Mr. Montgolfier attributed the 

 afcent of the machine, not to the rarefaftion of the heated, 

 air, which is the truecaufe, but to a certain gas or aeriform 

 fluid, fpecifically lighter than common air, which was fup-. 

 pofed. to be difengaged from burning fubftanccs, and.whichi 



has 



