284 Mr. Thompson’s Experiments 
what it was in the 76th and 77th experiments before mentiond, 
when the velocities fliewn by the recoil and by the pendulum 
were aimoft exactly the fame, I am inclined to believe, that 
there rauft have been fome miftake in determining: the vela- 
cities by the pendulum in thefe laft experiments, and that the 
velocity (hewn by the recoil is moft to be depended on. 
With 290 grains, or half the weight of the bullet in pow- 
der, in the 48th, 49th, and 50th experiments, the recoil was 
22,58, 22,92, and 22,38 ; and the recoil, with the fame charge 
of powder, without a bullet, at a mean of the 60th and 
99th experiments, was 10,66. The mean of the velocities 
of the bullets, computed from the recoil, is therefore 1416 
feet in a fecond, and the velocity fliewn by the pendulum was 
1427 feet in a fecond : the difference is not confderablc. 7 he 
mean of the velocities in the 109th, noth, 111th, and 
1 1 2th experiments is by the recoil 1464, and by the pendu- 
lum 1 444 feet in a fecond. 
With 330 grains of powder the velocities of the bullets 
appear to have been as* follows, viz . 
Vent at o. Vent at 1,3. Vent at 2,6. 
By the recoil 154 3 1620 1610 
By the pendulum 159 4 1625 1528 
See the 62d, 63d, 64th, 65th, 66th, 67th, and 17th 
experiments. 
The uniformity of the recoil was in all cafes very remarkable. 
Thus, in the firft fet of experiments with 290 grains of pow- 
der (from the 48th to the 5 7 th experiment inclufive), the recoil 
was, 
Vent 
