Mr. Thompson’s Experiments 
3 H 
MISCELLANEOUS EXPERIMENTS, 
Of fine unjut c'tfsful attempts loincreafe the force of gun-powder. 
It has been fuppofed by many, that the force of fteam is 
even greater than that of gun-powder; and that if a quantity 
of water, confined in the chamber of a gun, could at once be 
rarified into fteam, it would impel a bullet with prodigious ve- 
locity. Several attempts have been made to fhoot bullets in this 
manner ; but I know of none that have fucceeded ; at leaft fo 
far as to render it probable that water can ever be fubftituted in 
the room of gun-powder for military purpofes, as fome have 
imagined. 
The great difficulty that attends making thefe experiments 
lies in finding out a method by which the water can at once be 
rarified, and converted into elaftic fteam; and it occurred to 
me, that poffibly that might be efife&ed by means of gun-pow- 
der, by confining a fmall quantity of water in fome very thin 
fubftance, and furrounding and inclofing it with powder, and 
afterwards fetting fire to the charge. The method 1 took to do 
this was as follows. Having procured a number of air blad* 
ders of very fmall fifties, I put different quantities of water 
into them from the fize of a fmall pea to that of a fmall piftol 
.bullet, and tying them up clofe with fome very fine thread, I 
hung up thefe little globules in the open air till they were quite 
-dry on the outfide. I then provided a number of cartridges 
made of fine paper, and filled them with a known quantity of 
jpowder, equal to the cuftomary charge for a common horfe- 
man’s piftol ; and having loaded fuch a piftol with one of them 
