Experiments upon Gimpowder. 57 



Velocity of the Bullet. 



Weight of The Barrel heavier The By the By the 



The Experiments, the Bullets, than the Bullet. Recoil. Recoil. Pendulum. Difference. 



The charge of powder consisted of 145 grains in 

 weight in each experiment. 



In order to shew in a more striking manner the re- 

 sult of these experiments and the comparison of the two 

 methods of ascertaining the velocities of bullets, I have 

 drawn the Fig. 16 where the numbers that are marked 

 upon the line AB are taken from A towards B, in pro- 

 portion to the weights of the bullets ; while the lines 

 drawn from those numbers, perpendicular from AB 

 (as w, v, for instance at the number 2352) and ending 

 at the curve c y d, express their velocities as shown by the 

 pendulum. The continuations of those lines on the op- 

 posite side of the line A B shew the recoil, and also the 

 velocities of the bullets as determined from it: thus 

 w, r, and the (dotted) lines parallel to it, which end at 

 the line g, /, express the recoil ; and the portion of each 

 of those lines that is comprehended between the line 

 AB and the curve m, n, (as w, ,) is as the velocity of 

 the bullet in the several experiments. The line A^ e, 

 denotes the weight of the charge of powder ; and the 

 line A, m. the velocity with which the elastic fluid escapes 

 out of the piece, when the powder is fired without any 

 bullet. 



