ffective range, whether the
actual distance had been correctly ascertained or not.

The deviation of projectiles is, however, generally increased by
ricochet, and in proportion to the roughness of the surface of the
water. Even a slight ripple will make a perceptible difference not
only in direction, but in range and penetration, and the height to
which the projectile will rise in its bounds.

Although these facts demand attention, yet when the estimated distance
does not require an elevation of more than three degrees, projectiles
from guns pointed rather too low for direct firing will probably
ricochet and strike the object with effect, even when the water is
considerably rough. This may be called "accidental ricochet."

When the water is not smooth, the most favorable circumstances for
ricochet firing are when the flight of the shot is with the roll of
the sea, and that roll is long and regular.

Ricochet will be effective against small objects up to 2,000 yards,
but should not commence at less than 600 yards; at less distances it
is preferable to fire direct. Ricochet is of no value from rifled guns
firing elongated projectiles, as they lose all certainty of direction
on the rebound.

Upon smooth water, a shot fired horizontally from the 32-pdr. of 33
cwt., with 4-1/2 lbs. powder, ricocheted and rolled about 3,000 yards;
the greatest range obtained from an elevation of 5 deg., with the same gun
and charge, was less than 1,800 yards. _See_ Dahlgren's Report on
32-pdr. of 32 cwt., p. 90.

Shot rarely ricochet at all with elevations above 5 deg., and the bounds
are always higher, with equal charges from the same gun, as the
elevation of the gun is increased.

319. Concentration of fire may be desirable under certain
circumstances; and arrangements have been sometimes made to secure it
by the simultaneous discharge of a number of guns upon some part of an
object whose distance is known.

The advantages of these arrangements are not very obvious, excepting
in cases where the position of the enemy may be visible from one part
of a ship and not from all the guns in the batteries.

The object sought to be obtained is therefore to aim from in-board at
an invisible target, the distance and direction of which are indicated
by the Captain. It is consequently necessary that he shall be so
placed as to obtain a distinct view of the enemy, or have suitable
observers to inform him of his exact position.

320. In genera