273 
the Force of fired Gunpowder, 
when the irregularities of the line AC (which, as had already 
been observed, must be attributed to the unavoidable errors of 
the experiments), are corrected, these two curves will be found 
to coincide with much precision throughout a considerable part 
of the range of the experiments ; but towards the end of the 
set of experiments, when the charges of powder were consider- 
ably increased, the elasticities seem to have increased faster 
than, according to the assumed law, they ought to have done. 
From this circumstance, and from the immense force the charge 
must have exerted in the experiment, when the barrel was 
burst, I was led to suspect that the elastic force of the fluid 
generated in the combustion of gunpowder, when its density 
is great, is still much greater than these experiments seem to 
indicate ; and a farther investigation of the subject served to 
confirm me in this opinion. 
It has been shown that the force exerted by the charge in 
the experiment in which the barrel was burst could not have 
been less than the pressure of 54,752 atmospheres ; but the 
greatest force of the generated elastic fluid, when, the powder 
filling the space in which it is confined, its density is = 1000, 
on computing its elasticity by the theorem a: 1+0 00 ° 4JC = y, turns 
out to be only equal to 29,178 atmospheres. 
In this computation the mean of the results of all the expe- 
riments in the foregoing set is taken as a standard to ascertain 
the value, expressed in atmospheres, of y, and it is y x 1.841 
= 29,178. 
But if, instead of taking the mean of the whole set of expe- 
riments as a standard, we select that experiment in which the 
force exerted by the powder appears to have been the greatest, 
