TRACT 34.

IN GUNNERY.

353

The diameter of the gun bore being 2 - 02, andthe diameter of the ball - - - 1-95, consequently

the windage was - - - - - 0-07

Mean length of the charge of powder 10-6

The two oaken plugs which were driven in, to fill up theholes, after the 8th and 9th rounds, weighed about l*. oz.to each inch of their length. The whole weights of theseplugs, and the weights of the balls lodged in the block,were continually added to the weight of the pendulum,to complete the numbers for the values of p in the 9thcolumn ; and from these numbers the correspondent valuesof g and », in the next two columns, are computed by theirproper corrections in Arts. 23 and 25. After which, thevelocities contained in the last column are computed by theformula in Art. 24. And the medium among all these velo-cities, as well as that of the recoils of the gun, are placed atthe bottom of their respective columns.

from the mean recoil with ball 35‘0take the recoil without a ball 23'4there remains - - - - c = 1T6

Then, having b = T051, and r = 10 6’5, by the rule12718 x -^yin Art. 36, we have only 1315 feet, for thevelocity of the ball as deduced from the recoil of the gun ;which is 141 less than the velocity found by the vibration ofthe pendulum, or about T Vth 0 f the whole velocity.

The powder blown out unfired was not much. Theapparatus performed all very well, except only that thewood of the pendulum seemed not to be very sound, as itwas pierced quite through by the end of this day’s experi-ments ; though the sheet lead with which the back wascovered, as well as the face, just prevented the balls andpieces of the wood from, falling out at the back of thependulum.

von. ii.

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