434 -Abbe Fontana’s Account of Airs 
remainder, when treated with the tafte of nitrous air, 
gave II- 4, 11+ x (a> ; when the common atmofpheric air 
treated with the fame nitrous air gave II— 4, 11 + 8. It 
was therefore fenlihly better than the atmofpheric air, 
which, during three years of experiments made at Paris, 
I have conftantly found to be inferior to the air of the 
Seine water, extracted as above. 
Having repeated the experiment, I received the air 
into two different receivers. The firft of which, by be- 
ing fhaken in water, was diminifhed in the proportion of 
ten to feven ; and by the teft of nitrous air gave II- 14, 
11 + 1, Ill+x, when the common air gave II- 12, 11 + 6, 
III +6. 
The fecond quantity of air was diminifhed in the pro- 
portion of three to one; and when examined by the teft 
of nitrous air gave II±o, III±o. From whence it may 
be concluded, that the firft air was better than the atmo- 
fpheric air ; whereas the fecond was worfe, and mixed 
with much fixed air. 
Being in doubt whether the tin veflel employed in 
the experiment above mentioned might not alter the 
nature of the air, See. I made ufe of glafs veffels. Hav- 
ing therefore filled one of thefe veffels, having a long 
neck bent in two directions, with the Seine water, I 
1 
(a) See p. 343. for an explanation of this meafure. 
obtained 
