the Force of Fired Gunpowder. 157 



reasons which appeared to me to prove that, though the 

 inflammation of gunpowder is very rapid, yet the progress 

 of the combustion is by no means so instantaneous as 

 has been imagined. I shall now give an account of some 

 experiments which put that matter out of all doubt. 



It is a fact well known, that on the discharge of fire- 

 arms of all kinds, cannon and mortars, as well as mus- 

 kets, there is always a considerable quantity of uncon- 

 sumed grains of gunpowder blown out of them ; and, 

 what is very remarkable, and as it leads directly to a dis- 

 covery of the cause of this effect is highly deserving of 

 consideration, these unconsumed grains are not merely 

 blown out of the muzzles of fire-arms ; they come cut 

 also by their vents or touch-holes, where the fire enters to 

 inflame the charge ; as many persons who have had the 

 misfortune to stand with their faces near the touch-hole 

 of a musket, when it has been discharged, have found to 

 their cost. 



Now it appears to me to be extremely improbable, if 

 not absolutely impossible, that a grain of gunpowder, 

 actually in the chamber of the piece, and completely 

 surrounded by flame, should, by the action of that very 

 flame, be blown out of it, without being at the same time 

 set on fire. But if these grains of powder are actually on 

 fire when they come out of the piece, and are afterwards 

 found at a distance from it unconsumed^ this is, in my opin- 

 ion, a most decisive proof, not only that the combustion 

 of gunpowder is by no means so rapid as it has generally 

 been thought to be, but also (what will doubtless appear 

 quite incredible), that if a grain of gunpowder, actually 

 on fire, and burning with the utmost violence over the 

 whole extent of its surface, be projected with a z'ery great 

 velocity into a cold atmosphere, the fire will be extin- 



