The Press.
London, England, 1857-04-25 00:00:00

AMERICAN STEAM FRIGATES.

A CONSIDERABLE discussion has arisen in naval
circles as to the relative Oficiency in war between
heavyarmed steam frigates and screw line-of-battle
ships. The question is as much one of speed
as of armament. The Americans are building
enormous heavy-armed steam frigates. We devote
our energies to the construction more of leviathan
liners, swifter, it is true, but with guns of less range.
The point raised is, whether we should not also
build steam frigates at least to match, if not to
excel, any afloat.
The Merrimac, when at Spithead a short time
since, attracted the attention of our naval authorities.
She was the first of that fleet of heavy-armed steam

frigates which our recent demonstration in the
American seas has created. A second, the Niagara,
about to be employed in laying down the Atlantic
submarine telegraph, wiU soon be over here. The
following description of her is taken from the
American papers :
The hull is of live oak, varying in width and thickness
from 22 inches by 14 near the keel to 11 by 8 on deck.
The keel is 320 feet long •, length on deck, 345 feet;
breadth of beam over all, 55 feet; depth of hold, 31 feet 8
inches. Four boilers and three horizontal engines of
1,000-horse power, built by Pease and Murphy, constitute
her propelling power. The cylinders are 72 inches in
diameter and 8 feet stroke. All of this machinery,
weighing over 500 tons, is applied to turn a single
propeller of 18 feet diameter. To protect the machinery
from shot in action it is all inclosed by immense iron
coal-bunkers, overarching and descending many feet
below the water-line. He chimneys are telescopic,
and while she is under sail or in battle may be lowe ed
almost out of sight. The engine and fire rooms are
perfect iu their way, and, being well supplied with ample
ventiliito.rs, will probably be as cool and comfortable as
can be desired.

The Niagara will rely for speed mainly on her siding
abilities, and although the fires will always be kept b. dded,
and everything in readiness for getting up steam at short
notice whenever required, she will, unless in calms and on
extraordinary occasions, be only a clipper frigate. Her
model is that of a mammoth clipper, with shallow forefoot,
sharp, high bow, and hollow water•lines. View her as we
will, not a single straight line is presented. Ever where
she curves fluent and free, challenging the admiration of
the most critical by her vast yet perfectly symn etrical
proportions. She sits on the sea " like a th ng of
life," and when careering before a twelve-knot I reeze
one would feel on her as though he were astride a fleet,
high•mettled courser, bounding along on the wil go of
the wind.

When under full sail she will spread about 14,000
running yards or 7,000 square yards of canvas, a d it is
anticipated that her speed tinder canvas will be lb or 16
knots, and under steam 11 or 12 knots an hour. Her
mainmast is 1•4 feet above deck, 111 feet in e treme
height, 371 inches in diameter; foremast. 74 fe• t above
deck, 101 feet in extreme height, and 3.5 1, i hes in
diameter; mizenmast. 8.5 feet in height, and SO inches in
diameter. Her mainyard is 106 feet in length, and her
foreyard 94 feet. Her armament will comist of 12
great guns of 11 inches bore, 12 feet in length, and
capable of throwing shot of 170 pounds and shells of 130
pounds weight. These guns were all cast at the West
Point Foundry, but will not be put on bawd until after
she has finished her peaceful task of laying the great sub-
marine cable.

One great feature in this vessel is her high and airy
decks. Between the bottom or orlop and terth decks
the height is 6 feet 6 inches ; between the lower and
main decks, 8 feet 8 inches; between the main and spar
decks, 7 feet 3 inches. The main deck, on which the
officers and most of the men live, is admirably lig htel
by a multitude of dead-lights, and thoroughly esatilat4.l