THE RIFLE ON MOVING GAME. 301 



parallelogram in the second case is only one thirtieth 

 of the width of the one in the first case. 



Suppose now the train containing the rifle were at 

 rest, but the rifle were a hundred yards long, or long 

 enough to follow the mark and keep its muzzle against 

 it while the ball was passing up the barrel. The ball 

 would in such case hit the mark although the breech 

 of the rifle were at rest. Because in such case the ball 

 is carried along sidewise by the constantly increasing 

 motion of the long extended barrel. And now sup- 

 pose the barrel to be only three feet long instead of 

 three hundred feet, but following the mark with the 

 line of sights. What will then become of the ball ? If 

 those be correct who insist that the lateral motion of 

 the gun in following game is sufficient, the ball will 

 follow the same sidewise course as if it were still acted 

 upon by the constantly increasing lateral swing of the 

 three-hundred-foot barrel. In other words, if one half 

 of the long barrel were slit off for two hundred and 

 ninety-seven feet on the side opposite the direction 

 the mark is moving, so that the ball can escape from 

 the side of the barrel at any point beyond three feet 

 from the breech, the ball will nevertheless decline to 

 escape and hug the other half of the barrel as closely 

 as it did when the barrel was whole. There is no 

 possible escape from this conclusion. The ball must 

 take the same course in the half-open barrel that it 

 does in the whole one, or it cannot get far enough to 

 one side to reach the mark. Whether the ball will 

 leave the opening or not is an experiment any one 

 can easily try by whirling a ball up a tin tube slit off 

 in the same way as the barrel. 



For those who like more imposing philosophy I add 



