breaching solid stone walls, but are very effective against
earthworks, ordinary buildings, and for bombarding. For these purposes
a good percussion or concussion fuze is desirable, but no reliable
fuzes of these kinds have as yet been devised.

266. Solid shot should only be used when great accuracy, at very long
range, and penetration are required.

267. If, in loading, a shot or shell jams in the bore, no attempt
should be made to force it down, but it should be withdrawn. This may
be done with the ladle, by depressing and striking the muzzle against
the lower sill of the port, or by running the gun out hard against the
side at extreme depression.

268. A gun is not to be loaded with more than a single shot at once,
without the express sanction of the Captain, and never with more than
a single shell. Solid shot are not to be fired from shell-guns
without a direct order from the Captain.

269. Experiments show that firing two loaded shells together should
never be practised. With quite reduced charges [of from 1/8th to
1/12th the weight of the single shell], of 88 loaded shells thus
fired, 25 were broken and 48 did not explode, and some of the
remainder were exploded too soon by the shock of discharge. Of 50
unloaded 8-inch shells, fired two at the same time, with 6 lbs. of
powder, only one was broken by the shock of the discharge. This
difference between loaded and empty shells is accounted for by the
fact that a small hole is generally broken into the outer shell,
through which its charge is ignited. _See_ p. 13, Report of Admiral
Farragut, dated August 31, 1853, on experiments made at Old Point
Comfort.

270. In loading with a shell, the most exact attention is required to
all the precautions relating to the position of the fuze and the mode
of setting home the shell. The Loader is to be specially instructed
that unless the leaden patch is stripped off, to expose the priming,
the fuze will not ignite, and consequently the shell cannot explode.

271. Grape-shot have not sufficient penetration to be used with
effect, generally, against ships-of-war beyond 150 yards. When the men
on the spar-decks of the enemy are exposed, by the heeling of the
ship, grape or canister may be used against them, at distances varying
from 200 to 300 yards. Against light vessels, a single stand of grape
from heavy guns may be used at about 400 yards. The dispersion of the
balls is about one-tenth the distance, and is practically i