new inflammable Air or Gafs, Sec. 403 
By this calculation, which will, perhaps, be found 
more accurate than the former, one cubic inch of folid 
gunpowder will yield above 569 cubic inches of per- 
manent elaftic fluid: I fay, above 569 cubic inches, for 
I do not put into the account the claftic fluid which is ge- 
nerated by the fulphur, nor that which charcoal, con- 
fumed by the inflammation of the gunpowder, yields 
above the quantity mentioned, which it gives when 
heated in a glafs vefiel, by which it is by no means con- 
fumed, an ounce lofing by this operation only 60 grains 
of its weight. 
As this elaftic fluid will increafe to four times its bulk, 
it follows, that one cubic inch of folid gunpowder will 
extricate in the moment of explofion above 22 7 6 cubic 
inches of elaftic air. Which computation is not far from 
the refult of my former calculation, and that of Mr. 
BERNOUILLI. 
An accurate calculation of the expanfion of gunpowder 
would be a very difficult undertaking. The expanfion of the 
moifture always contained in gunpowder, however dry, 
may alfo contribute its fhare towards the amazing powers 
of this ingredient. Nitre contains from its nature a great 
ffiare of water, which is neceflary for the cryftallization of 
it, and charcoal is always found to contain it. We know, 
that 
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