204 op PROJECTILES.'

Whence it is easy to conceive; that in putting two shotsinto a gun, the velocity of each muit necessarily exceed halfof the velocity that one shot with the same cftarge wouklacquire; and the quantity of ihotion of the single shot isless than the sum of the quantities of motion of the two shot:but in ascertaining the effects of the three (hot, thetr forceafter passing through the men and horses being supposed to beentirely spent, the equation 8 = D u* vvi deb express's the effectsof one shot must be changed ; and to make up the excess,the initial velocity of each of the other two shot must exceed«\Z|; and each should strike a separate file. The pro-portion between the initial velocit acquired by one shot firedsingly, and that acquired by each when two shot are firedtogether with equal charges, can only be determined by ex-periment, as it changes whenever the char.;e is altered ; butit may be remarked, that in practice the velocity of each of

the two shot is less than u V {: wherefore the expedient ofputting two shot into a gun can be only advantageous whenthe enemy is drawn up in such a manner, that each shothas sufficient velocity to carry o.+ a file. For example, sup-pose the enemy be drawn ua eighteen deep, and each of twoshot fired together from an 8 pr. could strike a separate filewith an initial velocity os 978 feet, each of them w> uld de-stroy 18 men (197) : under this supposition there would be36 men destroyed by the two shot; while a shot of the samediameter, fired singly with an initial velocity of 1450 feet,could destroy only 18 men ; then its remaining velocity sussi- .cient to destroy 20 more would be useless.

CHAP. V.

Of the Effects of Case or Grape Shot inEngagements.

201. TPHERE are several kinds of (hot that come underthis head : one is formed of small pieces of iron of differentshapes and sizes put into cylinders of tin or pasteboard; thebases of which are closed by two circular pieces of wood.

A second