The Sun.
London, England, 1866-06-28 00:00:00

THE MIANTONOMAII.

To say that the Americans are a great people is
but to repeat a universally acknowledged aphorism.
They build a city, launch a fleet, or set an army in
the field in about the same space of time it would
occupy us in this grand, old, but slow-moving coun-
try to discuss the preliminaries. A pressing national
want felt by them is supplied at once, without refe-
rence to bewildered and bewildering " select cora-
n2ittees." Theoretical problems, in the art of war
especially, are reduced with astonishing celerity into
a practical, definite form, and the work, when com-
pleted, stands forth an accomplished fact, with its
virtues and its faults freely open to the criticism of
all Europe, and is, under all conditions, a striking
monument of the energy, decision, and practical
business sense of the statesmen and people of the
youngest and most powerful among the world's
family of nations.
One of the latest conceived and executed of these
Transatlantic prodigies is the two-turret vessel
Miantonomah, now anchored at Spithead, and in
allowing this vessel to visit England at the present
moment, the Government of Piesident Johnson has
conferred upon this country a service only secondary
to that so frankly rendered in the recent suppres-
sion of the miserable Fenian demonstration on the
shores of the Canadian lakes. The turret question
is just now to us a matter of vital importance with
regard to the constitution of our ironclad navy. It
ra:ty be eventually that iron-clothed fleets may be
composed wholly of turret or of broadside ships, or
that they may be composed of both, as with the
American navy, where turret ships occupy the posi-
tion of the heavy breaching artillery of the fleet, the
broadside ships being kept as the main body, avail-
able for general service where speed and power are
both combined in one vessel. No opportunity for
studying the whole subject with certain profit to
ourselves can be afforded equal to a visit to the
Iliantonomah and other turret ships of the Ameri-
can navy as they may visit our shores.
The Miantonomah is a sister vessel to the
Monadnock, now in the Pacific. As a war machine
for close heavy fighting she appears to be perfect.
The 15-inch Rodman guns are mounted on carriages
and slides very superior to anything before seen
England. The turrets are believed by the officers
of the ship to be invulnerable to any gun that can be
carried attoat. The sides of the ship are so low in the
water that nothing remains for an enemy to hit but
the turrets, aild they, with their two 450-pounders,
hit very hard in return. The training power of her
guns given by the revolving of her turrets is doubled
by reversing at any time the action of her twin
screws ; she is undoubtedly as safe and as seaworthy
as any vessel that ever floated as a man-of-
war ; she is, her officers say, quite as habitable as
any ordinary vessel they ever sailed in ; and she is
very much easier at sea than a broadside gun vessel
of the same tonnage would be. As a vessel of only
1,500 tons, carrying four 15-inch guns in their pon-
derous 10-inch iron turrets, the speed of the vessel
due from the proportion of her nominal engine
power to tonnage has been sacrificed by widening
and flattening the form of the ship's bottom, but
this has left her with a speed of eight knots, mean,
and is quite sufficient to enable her to fight any
action in her capacity of a turret ship, any want of
speed in manoeuvring which would be felt by avessel
of her class, driven by a single screw, being fully
compensated by the manoeuvring power given by
the reversed action of her twin screws.

The first impression felt on stepping on to the
Mia.ntonomah's deck at Spithead is that she would
make a welcome addition to the fixed forts on the
Horse and Noman shoals for the defence of Spit-
head, and also that she would as assuredly be an
efficient weapon with which to attack the same forts
and open a passage into Spithead for an accompa-
nying fleet of iron-clad broadside ships. Between
decks the visitor is at first bewildered by the quan-
tity of machinery scattered about. There are no
less than 17 steam-engines, large and small, on this
deck, and all have their apportioned work. Six of
these engines drive the blowers which receive the air
from the main air shaft (standing between the two
funnels on the upper deck, about 9ft. in height), and
distribute it along shaftings and up through gratings
in all parts of the ship, for at sea the ship is neces-
sarily battened down fore and aft, and the only air
that can enter the ship then, except down the main
air shaft, is through the perforated tops of the
turrets and pilot-houses. With two of the blowers
set slowly to work ou board yesterday there
was a strong upward rush of cool air through the
air gratings in the floor of the ward room and other
parts of the ship, the thermometer in the captain's
cabin previous to the blowers being set moving
marking 75 deg. There was, however, a feeling of
oppressiveness which was, perhaps, due to the ab-
sence of the greater portion of the daylight, and the
knowledge that air was being then breathed which
had been sucked into a part of the vessel below the
water line by mechanical means, through an iron
column communicating with the outer atmosphere.
All the officers of the Miantonomah declare that
they rather like being at sea in a closed vessel. They
get plenty of air below from the blowers, and must
do so as long as there is any steam to drive them,
and of the two, for comfort, they prefer for a sea
voyage a vessel like their own to an ordinary cruiser.
Indeed, the thermometer records kept on board
prove that the heat below during the voyage across
the Atlantic cannot have been so great as would be
imagined by a stranger looking over the ship as she
lies at Spithead and examining the means of supply-
ing and regulating the inboard draught of fresh air.
At sea, however, the upper deck is always awash
with the seas rolling over it, and this no doubt tends
to cool the atmosphere below. As a handful of facts
are, however, with a cartload of opinions, we give
here a copy of the thermometer register of the tem-
perature on the middle of the berth deck on four
days, or rather nights, during the voyage across :
Juno 12. Juno 13. Juno 14. June 15.
Deg. Deg. Deg. Dog.
10 pan 72 71 70 70
12 midnight.- 69 71 70 71
2 a.m 64 70 70 68
4 a•m 64 70 64 68
G a.m 6l 70 70 67
With regard to the seaworthiness of the vessel,
no vessel, her officers declare, could have behaved
better than the Miantonomah, and there was a suf-
ficiently stiff breeze experienced between New York
and Halifax to test her in that respect. The seas
rolled over her deck whenever the waves rose, on
the quarters, the bows, or broadside, but they
washed over without affecting the ship, and the
officer of the watch from his roomy perch on the
raised platform between the two turrets could look
with perfect equanimity upon the submerged hull of
his vessel below. In this respect the Miantonomah
only differs from many deep loaded sailing clipper
ships in having no bulwarks to hold the water on
her decks. Of the exact amount of work to be got
out of the 15in. guns there appear to be no exact
data available for comparison with the work of our
beat present ship gun, the 12 ton 9in. rifle, or 250
pounder. Commander Cornwall, of the Miantono-
mah, who commanded a monitor before Charleston,
once fired a total of 750 rounds from one of these
guns, but the greatest number he ever fired in one
day was 60 rounds. No phraseology would describe
the outline of this gun so well as the accepted
" soda-water bottle." Although of the immense dia-
meter of bore of 15in. at the muzzle, the outer dia-
meter there is only 21in., but the breech is im-
mensely weighted with metal. The gun is so evenly
balanced upon its trunnions that the captain of the
gun can elevate or depress it with one of his fingers
on the screw lever. The elevating screw is lain. in
diameter, and works loosely with its heel in
a flat-
bottomed aietal cup, so as to give with any sudden
shock from the gun. The carriages are, as already
stated, superior to anything of the kind previously
seen in this country. They are simply made, and
have a "continuity of strength" throughout. The
compressors are three iron plates working between
four wooden balks. The slide lies on a level with
the turret floor, and is merely two iron beams 9in.
by 3in., planed true on their upper edge, and con-
nected to beams and plates at each end. Two men
can run the guns in or out with ease, and one man
can regulate the compressors. The sights over the
top of the gun gave a range of 2,300 yards. The
extreme of the gun's elevation is 9 deg., and of de-
pression 34 deg. The turrets are Oft. in height above
the iron 3-inch deck, the 3-inch wood deck above

the iron deck being above the actual base of the
turret on the composition ring on which it rests.
When fitted to the ship the under surface of the
turret plates where they rest on the composition ring,
and the ring there itself, are both planed true, and
are always afterwards kept well oiled and greased to
reduce the friction when the turret is revolving.
Supposing that the turret is raised, as it is termed,
for revolving, the fact is that only about two-thirds
of the weight is taken on the spindle, the remainder
slipping round on the composition ring. The turret
is built of ten one-inch rolled iron plates, the surfar,es
of which are all carefully planed, and the whole then
set up together in a cylindrical form, each plate
breaking joint with its next neighbour. The bolts
are " marlin-spike " shaped, of less diameter, but
more numerous than in our turrets, and their heads
are clinched on the outer face of the turret, instead
of being cut off, as with us. The top of the turret
is closed in with iron bars, 4in. by 3in., which are
again covered with iron plating of one inch, per-
forated. The two gunports are each 2ft. wide by
3ft. 10in. in depth. They can be closed when the
gun has been discharged by a 13in. iron stopper,
which is pivoted on the floor and roof of the turret,
and easily swings into and out of position. The
pilothouse on the top of each turret weighs about
30 tons.

The side armour of the ship is 7ft. in depth from
the deck level to below the water line, and is formed
of seven one-inch plates.

The engines of the ship are of 800 horse power,
nominal, on the back action principle of Mr. Isher-
wood, United States Navy, the connecting rod work-
ing towards each cylinder head. The cylinders are
30in. in diameter, with a 27in. stroke of piston,
driven at full speed at 80 revolutions, with from 35
to 38 pounds of steam. The screws work inwards.
The average heat in the engine-room in coming over
averaged 80 deg., and in the stokehole 120 deg.

The main faultto be found with the Miantonomah
is that she has been constructed of wood instead of
iron. The enormous weight she has to carry in
turrets, guns, side and deck armour, engines &c., must
tell upon a wooden hull. If we compare her with
our own wooden-hulled Royal Sovereign, we find
her excelling our ship in smallness of target offered
to an enemy's shot, and in manoeuvring power by
the action of her twin screws. On the other hand,
the Royal Sovereign's turrets appear to be mounted
on a much better system by reason of the greater
diameter and strength of their central spindle and
the solid wide area of support given by the frames
of conical wheels under the turret turntable. The
Roy al Sovereign, too, is much more habitable than
the Miantonomah. On the relative merits of the
guns and armour of the two ships no one can give a
reliable opinion. The only method by which those
questions could be satisfactorily solved would be to
build two cylinders, one on the American and one
orr the English turret principle, and fire with two
guns at each turret, one gun being an American 15-
inch Rodman, smallbore, and the other a 9-inch
English naval 12 ton rifle. The power of the two
guns would thus be proved on each turret at oppo-
site sides, and the principles on which the turrets are
built respectively would also be satisfactorily tested.
One peculiar feature in the American turret was
almost omitted from notice—its ten one-inch iron
plates have no backing. The interior diameter of
the Miantonomah's turrets is 21ft., and their height
from floor to the overhead beams 6ft. 4in.