AEROSTATIC VOYAGE. 287 



Sauffiire junior alfo found, by ufing nitrous gas, that air The compofitioa 

 taken in the Col-du-Geant contained, within one httjndf^dth ° ( j^^'eveU 

 pari, as much oxigen as that of the . plain ; and his father where the fame, 

 afcertained the piefence of carbonic acid on the fummit of 

 Mont-Blanc: Moreover, the experiments of MM. Cavendim, 

 Macarty, Berthollet, and Davy, have confirmed the identity 

 of the compofition of the atmofphere over all the furface of 

 the earth. It may therefore be concluded generally, that 

 the conftitution of the atmofphere is the fame from the fur- 

 face of the earth to the greateft heights to which we can 

 afcend. 



Thefe are the two principal refults which I obtained from Recapitulation 

 my la'ft voyage. I have afcertained the fa<5t which had been re ""^ 



obferved by M. Biot and me, on the feniible permanence of 

 the intenfity of the magnetic power at a diftance from the 

 furface of the earth ; and betides, I think I have proved that 

 the proportions of oxigen and azote which constitute the at- 

 mofphere, do not vary fenfibly in the moft extended limits. 

 Many things ftill remain to be elucidated in the atmofphere, 

 and we hope the facls we have already collected will fo far 

 intereft the Inftitute as to induce them to deHre us to continue 

 our experiments. 



TABLE 



