A AES a esl a ee 
. 4 425 J 
in our élemént: and, indeed, { wa3_ 
much of that’ opinion, till Abbé 
Fontana convinced me of my error 
for, by keeping a’ bottle full of air 
taken from the atmofphere at the 
fame time, the conftitution of it is 
explored and accurately regiftered 3 
and examining fome time srretwards 
this very air, clofely fhut ‘up in a 
bottle, you find the refult of the 
trial to corre{pond exactly with the 
refult of that which was made at 
the time when-™ the” air © was taken 
from‘ the atmofphere, and ‘by no 
means conform with the refult of 
the trial inftituted ‘with the com- 
mon air of the day, unlefs it fhould 
happen that the conftitution of the 
atmofphere was juft the fame at 
both ‘times. I take this to be’ a 
demonttrative proof of the*excel- 
— of this method, as well as of 
the 
