286? 



AEROSTATIC VOYAGE. 



Analyfu 



of the atmojpheric 

 Mr. 



Anah/fis of the 

 Elevation of 



Aii 



Go: 



taken at an 

 6 Metres. 



Firft Ex- n 

 periment. 



Meafures. 

 "Atm. Air, 3. 

 Hyd. Gas, 2. 

 Refidue after 

 the combuf- 

 tion, - 3.04 



Air, 



Hyd. Gas, 

 Reiidue, 



- 



Meafures. 

 3. 

 2. 

 3.05 



2d Expe-^ 

 riment. 



Meafures. 

 r Atm. Air, 3. 

 Hyd. Gas, 2. 



L Refidue, 3.05 



Air, 



Hyd. Gas, 

 Refidue, 



- 



Meafures« 

 3. 

 2. 

 3.0 !> 



Atmofphenc air At the fame time one meafure of very pure oxigen gas 



and air taken at re q U i r ed 2.04 meafures of hidrogen gas: and this refult dif- 

 a great elevation, ' . .... 



are identically fermg only .01 from that obtained in experiments made on a 

 the fame. ve ry large fcale, and with great care, in the compofition of 



water, it is evident that great confidence may be placed in 

 our refults. They prove therefore that atmofpheric air, and 

 air taken at an elevation of 6636.5 metres, are identically the 

 fame, and that each of them contains .2149 of oxigen. On 

 analyzing the latter air by hydro-fulphuret of potafh, we 

 found in it .2163 of oxigen. I cannot give the refult of the 

 comparative experiment made on atmofpheric air, becaufe 

 we were unable to collect it; but the proportion of oxigen 

 which I have indicated, is alfo a little greater than that given 

 by the combuftion of hidrogen gas, and is comprized within 

 the limits of the variations found in the compofition of the 

 atmofphere at the furface of the earth, and which do not pre- 

 vent it from being considered as confiant. 

 This faft proved The identity of the analyfes of the two airs made by 

 by other expen- hidrogen gas, proves directly, that that which I brought did 

 not contain the latter gas ; nevertheless I alfo fatisfied myfeff 

 of it, by burning with the two airs only a quantity of hidro- 

 gen gas lefs than would have been rcquifite to abforb all 

 the oxigen gas; for I found that the refuiues of the com- 

 buftion of the two airs with the hidrogen gas were exactly 

 the fame. 



Sauffure 



