342^ Otiih^ prefent State of Aerojlat'ton. 



rachiite: for this rcafon I offered to Mr. Garnerhi, that, a» 

 his balloon was capable; of carrying four pcrfons, it would be 

 fully adequate to the convevance of two, together with the 

 parachute and ballafl. : undi^r fuch circuniilances it would be 

 neceflary to fufpend the parachute beneath the car; and my 

 intention was to occupy the latter myfelf. An ofler fo ad- 

 vantageous for fecuring Mr. Garnerin's uiachine (otherwife 

 left at random) was rejected by him, from the acknowledge- 

 ment of his doubts rciped.ing the event of fo novel an expe- 

 riment. But I truft this experiment will not long remain 

 unattended to by fuch as may have an opportunity of per- 

 forminoit: the cffefts lubleqaently taking place from the 

 lofs of a weight of upwards of 200 pounds at an elevation of 

 lo.coo feet, are not fo terrific as might be imagined; as 

 during this afler-afcent no danger could attach to the ma- 

 chine; for, its neck being open, and thereby affording an exit 

 to the gas, now fomewhat^more expanded by the abltnce of 

 the mechanical preffure of the 3 o pounds jult loft, vet gra- 

 dually ftill more expanding ilfelf as it attains in this alcenfioa 

 a zone of air of leiler denfity, would neccffarily prevent any 

 rupture from that caufe ; while, if the aeronaut found his re- 

 fpn-ation too much affeftcd to allow his attaims.ent of the ut- 

 niofl; height furmountable under thefe circumfiances, he could 

 have nothing to fear fo long as he h<is the vhIvc at command. 

 Neither have we any caufe for apprehenfion from the velocity 

 likely to take place, if the traveller is not too near to the body 

 of the balloon, or in a fitting pofition ; in both which cafes 

 it is doubtful whether the approximation to a vacuum * ia 

 the wake and immediately in the vicinity of the lower pole 

 ot a large fpherical body, afcending with great velocity, might 

 not endanger afphyxia, from the fuddenly diminifhed denfity 

 of the air received into the lungs f. 



At the fame time, to fuch as defcend by a parachute from 

 a balloon left at random, I would advife an attention to the 

 following fimple precaution, which cannot fail of infuring the 



* Agreeably to what wc learn in projeftiles, that a bodv moving with a 

 velocity of izoo feet in a fecond, leaves behind it an aftual vacuum ; alfo 

 exemplified in the common exercife of fwinging, where a flightly fuffo- 

 cating fcnfation is experienced in the retrograde motion of the machine, 

 occafioned by the perPjn fitting m the wake fornied by the recoil of his 

 own body. 



f As 1 have no intention to fpeak in this place of the effefts likely to 

 enfue to an aeronaut in cafes where, the valve being unexpcftccllv found out 

 of repair, he is obliged to remain at the then unavoidatile iquilibrium, I 

 ftall rcferve theft points of difculhon as the fubjedt of a paper I propofe to 

 tranfmit ar a future oppoi -unity, in immediate rcferenei to the probable 

 cSfccts of diminilhcd atmofpheric preffure on the animal lyftem. 



fpeedy 



