; g - 4 Dr. Austin’s Experiments on 
Exp. 10. Three meafures of inflammable air, after 1 50 ele£lrical 
fhocks, became 5,1. To this was added as much dephlogifti- 
cated air as increafed the column of air to 10^.. After inflam- 
mation it meafured about 4,9 ; and was reduced by lime water 
to 2 4 • This refidue was not inflammable. 
The contra&ion upon burning thefe airs was 5,93 ; and the 
quantity of fixed air appears to be 2,1 5. This fixed air requires 
2,15 meafures of inflammable air and3,oi of dephlogifticated air. 
Thefe deducted from the fum of the contraction leave 2,92, above 
what is fufficient to account for the fixed air produced. Sup- 
pofing this contraction to have been occafioned by the union of 
light inflammable and dephlogifticated air, 1,94 of the former 
muft have combined with 0,97 of the latter. It is evident, 
that the quantity of dephlogifticated air ufed in this experi- 
ment is more than fufficient to combine with both kinds of 
inflammable air. 
The fixed air produced in thefe experiments is 0,23 lefs in 
proportion, than'was produced, when the inflammable air was 
not decompofed in the feventh and eighth experiments. It 
appears by calculation, that thefe 0,23 were expanded to about 
ten times their bulk. It is obfervable, that the expanfion in 
this cafe is 2,33 ; and that the quantity of light inflammable 
air which combined with the dephlogifticated air, is only 
I 5 q 7j which is 0,40 lefs. This proves, that it is very difficult, 
if not impoffible, to unite the whole of thefe airs ; and that a 
fmall quantity will remain diffufed in the refidue, unlefs the 
airs be much purer than I have been able to procure them ; yet 
it is not probable, that fo large a proportion of light inflam- 
mable air as 0,40 Ihould efcape combuftion, over and above 
what efcapes in fimilar circumftances, when no light in- 
flammable air is prefent. The addition of light inflammable 
