142 Dr. Priestley’s Experiments on the 
had difappeared ; but as this was effefted by the nitrous air uniting 
with all the dephlogifticated air contained in the common mafs, 
and as they unite in the proportion of one meafure of dephlo* 
gifticated air to two meafures of nitrous air, one-third of the 
0.93 m. viz. 0.31 m. will be the quantity of dephlogifticated 
air that was contained in the one meafure of common air oil 
which the experiment was made, the remainder, viz. 0.69, 
having been phlogifticated air. The common air contained in 
the tube would have been 1.23 oz. in. ; but deducing from is 
one-twentieth in the whole, it will only be 1.17 oz. m. I 
then fay, if one meafure of this air contains 0.69 m. of phlo- 
gifticated air, 1.17 oz. m. will contain 0.8073 oz. m. of phlo- 
gifticated air. This, therefore, was the quantity of phlogifti- 
cated air which had been expofed to the adtion of the acid of 
nitre in the tube. 
In order to find how much of the fame kind of air was con- 
tained in the tube after the procefs, I examined the refult above 
mentioned in the following manner. Since two meafures of 
nitrous air, and one of this refiduum, were reduced to 1.02 m. 
it is evident, that 1.98 m. had difappeared, and confequently 
one-third of this quantity, viz. 0.66 m. had been dephlogifti- 
cated air, and that the remainder of the meafure, viz. 0.34,. 
had been the proportion of phlogifticated air in one meafure 
of this refiduum. If then one meafure of this refiduum con- 
tains 0.34 m. of phlogifticated air, 2.03 oz. m. will contain 
0.6902 oz. m.. which is lefs than 0.8073 oz. m. the quantity 
contained in it before the procefs ; fo that a part of the phlo- 
gifticated air had been either abforbed or decompofed, its phlo- 
gifton having been imbibed by the acid at the fame time that 
it had emitted the dephlogifticated air. 
In 
