292 Mr. Thompson’s Experiments 
not be pin, or rather that the motion of the bullet does not 
O y 
begin to be retarded, till it has got to the diftance of two feet 
from the muzzle. The diftance, therefore, between the barrel 
and the pendulum, inftead of 12 feet, is to be eftimated at 10 
feet ; and as the bullet took up about _-i T part of a fecond in 
running over that fpace, it mull in that time have loft a velo- 
city of about 335 feet in a fecond, as will appear upon making 
the computation, and this will very exaCtly account for the 
apparent diminution of the velocity in the experiment ; for the 
difference of the velocities, as determined by the recoil and by 
the pendulum, — 2 109 - 1 763 = 346 feet in a fecond, is ex- 
tremely near 335 feet in a fecond, the diminution of the velo- 
city by the refiftance as here determined. 
If the diminution of the velocities of the bullets in the two 
fubfequent experiments be computed in like manner, it will 
turn out in the 86th experiment = 65 feet in a fecond, and in 
the 87th experiments 33 feet in a fecond; and making thefe 
corrections, the comparifon of the two methods of afcertaining 
the velocities will ftand thus : 
85th exp. 
Velocities lhewn by the pendulum, 1 7 63 
Add the diminution of the velocity I 
E D D j 
by the refiftance of the air, j 
2098 
Velocity by the recoil, - 2109 
The difference V = + 1 1 
I 
So that it appears, notwithftanding thefe corrections, that 
the velocities in the 86th and 87th experiments, and particu- 
larly in the laft, as they were determined by the pendulum, are 
{till 
86th exp. 87th exp* 
1317 1136 
6 5 33 
I382 I169 
I43O 1288 
+ 48 +H9 
