ON ATMOSPHERICAL AtR. 100 



fame the following forms ; i.e. x +5/ = 100, and 1 103 r + 

 9833^=100000. Multiply the former by 985, fubtrad the 

 produd from the latter, and you will have the following equa- 

 tion ; i.e. 118jt:=1500: Hence by dlvifion, a:=:12,|^; 

 and the excefs of 100 above this number gives j/ = 87,|^. 

 The ftep<; of this procefs have been detailed minutely, with a 

 view to enable the chemical reader, who has the leall know- 

 ledge of algebra, to confider the grounds of the following 

 •conclulions, and to form his own judgment refpe6ling the 

 weight of them. 



It is evident from the foreproinpr calculation, that if 1 00 parts Air not a mix- 



r • r , • . .• r u • .» ture of oxigen. 



or a mixture of Ine oxigenous and azotic gales, having the ^^yg g^^ ^^otic 

 fpecilic gravity of common air, were deprived of their oxigen ga^es. 

 in a graduated tube, the reliduum would meafure foraethin* 

 more than 87 fuch parts, ?'. e. S7 ,\^. But when an equal 

 bulk of the atmofpherical fluid is treated in the f^me manner, 

 the portion of it which remain*; unabforbed, is much lefs than 

 the preceding quantity ; M. Chaptal makes it to be 72 fuch 

 parts, and fome writers call it 78, the mean of which is 75. 

 Now if we fubtra6l any one of thefe numbers from the refi- 

 duum fixed by calculation, a difference will be found, which 

 cannot be referred to the unavoidable imperfections of eudio- 

 meters, becaufe it could hardly efcape obfervation in any in- 

 ftrument of the kind, the leaft excefs being more than nine 

 parts, or nearly a tenth, of the whole fcale of 100 parts. On 

 the other hand, a mixture of 72 parts azote and 28 oxigen, or 

 • of 78 of the former and 22 of the latter, exceeds an equal bulk 

 of common air in weight ; confequently the atmofpherical 

 fluid is not a mechanical mixture of the two gafes in queflion, 

 if any credit be due to the experimental data. 



Though air has been fliewn not to coniifl of the oxigenous Air a gafeous 

 and azotic gafes Amply mixed together, it is certainly a com-*'*"*^*'^"*'^^' 

 pound that maybe refolved into thefe two principles: For 

 betides fupporting refpiration and combuflion, it converts me- 

 tals into oxides, and the nitrous gas into nitric acid; therefore 

 it contains the oxigenating principle. On the other hand, 

 when air is employed to oxigenate bodies, the refiduum of 

 it is azotic gas of greater or lefs purity; confequently the at- 

 mofpherical fluid is a gafeous oxide of azote, which can be 

 decompofed by art, though chemifts have not as yet difco- 

 vered a certain method of producing it at pleafure, by uniting 

 the oxigenating matter to th^ azotic bafe. 



Fafls 



