The Cecil Whig. [volume] (Elkton, Md.) 1841-current, 1862-12-20
Ordnance nt-Guns and Iron
Ckads.

Captain j. A. Dahlgren, chief of the
Ordnance Department, has presented a
long report to The Secretary II the Navy,
from which we condense some interesting
information. He states that there is
now prospect of obtaining considera-
bic amount of inter for the manufac ,ure
Of gunpowder, from our own resources,
but the chief supplies for the whole
world arc still! in the hands Of the Brit
ish, and are obtained from the East
Indies. There are several private estab
lisments fabricating cannon for the navy,
viz: Knapp 4 Rudd, Pittsburgh, Pa:
Algcr & Co., Boston, Mass; r. p. Par
r9tt 4 Co., Cold Spring, N. Y; j.
Sparrow, Portland, Maine Ilinckley
4 Williams, Boston, Mass; u. Chaffee,
Providence, r. l., and Seyfert & Nc
Manus, Reading, Pa.
lRoN-CLAD SHIPS.
The use of solid shot fred from 10
Founders at sea, ceased at the battle of
Navarino. After this Captain Paixhan
introduced shells. The terrific effects
of these were first really displayed at
Slnope, by the Russians. In 1855 the
French first used three iron-clad vessels
at the Kinburn forts, and none Of the
Russian shot was able the pierce the
pla ing. The first sea-going iron clad
frigate built was La Gloirc, and England
soon followed the example with the War
rior. These are large vessels, Of great
draught. The American coast being
mostl y shoal requires vessels of light
draught, hence they are inaccessible to
heavy iron-clads like the French and
English frigates. Vessels of the
Monitor and lronsides classes are likely
to suit our present purposes. Captain
Dahlgrcn states that Whitworth first
demonstrated that thick iron plating,
backed with wood, could be pierced with
shells. The ll-inch guns of the Moni.
tor were chiefly designed for shells,
which were computed 10 have an initial
velocity of about ! ,l2O feet per second ;
bu. this class of gun is capable of throw
ing l69-pound solid shot with 80 lbs. Of
powder, and an initial velocity of hoo
feet per second. The Merrimac was
armed with 9inch guns their shot did
no ma crlnl damage to the Moni or the
damage which the shot of the latter
effected is not known. The wrought
iron shot furnished to the Monitor
weighed lS6 lbs. Ii fired with - lbs.
of powder, their initial velocity would
only have been $50 feet per second, -
The Monitor only fired ~ shots at the
Merrimac, and many of these failed to
strike, from difficulty of aiming with
precision. The Monitor and Galcna
failed to make any impression in the
attack Oh Fort Darling, on the james
river, because their guns could not be
sufficiently elevated.
GUNS FOR IRoN-CLAps.
RiAed shot is the most accurate at
long ranges, but when they strike and
are DETECTED, they tumble over and have
a very erratic flight. Such shot, there
fore, have no capacity for ricochet firing,
which is one of the most certain modes
of operating in naval sevicc when round
shot is used. Rife shot have greater
penetrating but less persuasive power
than round shot. The rife gun, how
ever, is gradually making its way into
the service. The Galcna was fired upon
at Fort Darling with round shot from
81 Founders. These passed through
her plating, and the entire s structure of
the vessel was much damaged.
An ll-inch gun can be fired once per
minute with wcll-disciplined crew ;
but some Improvement must be made
before q l5-incb gun can be fired once
in three minutes. The Roanoke, which
is being converted into an iron-pla'ed
turret ship will be able to throw 300
lbs. of shot at once. The effect of her
shell of $50 lbs, and solid shot of $50
lbs, from l5-inch guns, will be damag-
ing beyond former experience. One
of the l5-inch guns has been tried
on 5a-inch iron plates backed with Is
inches of oak, and placed at 900 yards
distant. The shot passed through this
target with ease. One of the 1l-inch
cast-lron guns tweighing 10000 lbs, J
has been fred 1875 times, with charges
varying from 20 to 80 lbs. of powder
and shot of l65 and l69 lbs. This gun
does not exhibit any signs of giving way
A great number of experiments with
chcsc cast-lron guns afford proof that
they are as strong and durable as the
forged British guns.
COAST DEEENsEs.
Captain Dahlgren states that batteries
Of masonry should not be exposed to
rifle cannon. The exterior of stone and
brick forts should be covered with iron.
The low stone forts at the Narrows of
New York are not well calculated to
hinder the passage of an iron-clad YES
sci. The earth works on a high eleva-
ton arc superior. Steam rams will be
of Ii tie use, unless their speed is great
err than that Of her vessels. Floating
iron-clad batteries should be employed
to assist fors in cage of an attack by
iron-clad friga.es.
Dome OF the Capitol at washington.
The National Mtellagencar states
that the great dome of the capitol
designed by Thomas U Walker, and
now in course of construction under his