52 Experiments upon Gunpowder. 



The weight of the barrel, together with its carriage, 

 was 47^ pounds, to which three quarters of a pound is 

 to be added on account of the weight of the rods by 

 which it was suspended, which makes W = 48 pounds, 

 or 336,000 grains ; and the weight of the bullet was 

 580 grains. B is, therefore, to W as 580 is to 336,000, 



... i i / V II V W 



that is, as i is 579.31 very nearly; and v (= - - -) 



is equal to V U -j- 579-3 l 



The value of V U answering to the experiments 

 before mentioned was found to be 1.8522, consequently 

 the velocity of the bullets ( = v) was 1.8522 X 579-3 1 

 = 1073 f eet m a secon d, which is extremely near 1083 

 feet in a second, the mean of the velocities, as they 

 were determined by the pendulum. 



But the computation for determining the velocity of 

 a bullet upon these principles may be rendered still 

 more simple and easy in practice ; for the velocities of 

 the recoil being as the chords measured upon the rib- 

 bon, if 



c be put equal to the end of the chord of the recoil, 

 expressed in English inches, when the piece is fired 

 with powder only, 



and C = the chord when a bullet is discharged by 



the same charge, 

 then C c will be as V U, and consequently as 



r x w , which measures the velocity of the bullet; 

 B 



the ratio of W to B remaining the same. 



If, therefore, we suppose a case in which C c is 

 equal to one inch, and the velocity of the bullet be 

 computed from that chord, the velocity in any other 

 case in which C c is greater or less than one inch, will 

 be found by multiplying the difference of the chords C 



