the Force of fired Gunpowder. 239 
gunpowder occurred to me many years ago; but a very expen- 
sive and troublesome apparatus being necessary in order to put 
it in execution, it was not till the year 1792, when, being 
charged with the arrangement of the army of his most Serene 
Highness the Elector Palatine, reigning Duke of Bavaria, 
and having all the resources of the military arsenal, and a num- 
ber of very ingenious workmen at my command, with the per- 
mission and approbation of his most Serene Electoral High- 
ness, I set about making the experiments which I shall now 
describe: and as they are not only important in themselves, 
and in their results, but as they are, I believe, the first of the 
kind that have been made, I shall be very particular in my ac- 
count of them, and of the apparatus used in making them. 
One difficulty being got over, that of setting fire to the pow- 
der without any communication with the external air, by caus- 
ing the heat employed for that purpose to pass through the 
solid substance of the barrel, it only remained to apply such a 
weight to an opening made in the barrel as the whole force of 
the generated elastic fluid should not be able to lift, or displace ; 
but in doing this many precautions were necessary. For, first, 
as the force of gunpowder is so very great, it was necessary 
to employ an enormous weight to confine it ; for, though by 
diminishing the size of the opening, the weight would be les- 
sened in the same proportion, yet it was necessary to make 
this opening of a certain size, otherwise the experiments would 
not have been satisfactory ; and it was necessary to make the 
support or base upon which the barrel was placed very massy 
and solid, to prevent the errors which would unavoidably have 
arisen from its want of solidity, or from its elasticity. 
The annexed drawings (Tab. V.) will give a complete idea 
