The Sun.
London, England, 1861-03-21 00:00:00

TIIE NAVY.

r The screw steamship Gibraltar, 101, the trial of
the machinery of which outside Plymouth Break-
water has been several times postponed, in conse-
quence of the boisterous state of the weather, was
built at Devonport from the lines of Sir B. Walker,
and launched in August, 1860. She is 252 feet long,
68 feet 6 inches broad, has a depth of hold of 25
feet 6 inches, and measures 3,715 tons. Messrs.
Maudslay and Field, of London, manufactured her
engines—a pair of 400-home power nominal, or
what is termed 800 collective. They have been
exerted up to an indicated power of 3,442 horses in
Keyham basin. The engines, double piston direct
horizontal, are, with the boilers, seated between the
foremast and mainmast—with the exception of some
modern improvements they are similar to those
fitted about eight months since on board the Revenge,
91, The steam from her boilers is conveyed from the
stokehole to the engineroom in one large pipe, which
is connected on both sides by junctions with the
boilers ; while in the Gibraltar there are two pipes
close to the boiler, so that besides other advantages
a great saving of space is obtained over head for
ventilation. In the engineroom the main steam pipe,
instead of being over the cylinders, goes round the
back, by which more room is obtained for getting
off the side-valve covers, &c. The cylinders proper
are completely enclosed in outer iron cylinders or
steam jackets, having between the two a space of
three inches, supplied with steam by separate
pipes. The Gibraltar's are the first screw engines
fitted in this manner. The engines of the Revenge
are fitted with a rack and pinion, and a single
port slide ; those of the Gibraltar have double port
slides and a screw instead of a rack, as a safer and
easier mode of reversing. The feed pipes are in
the former ship run under the stokehole floor ;
in the latter they are overhead. The hold of
the Gibraltar is deeper by about 18 inches, which
gives ample space between the boilers and the
orlop deck, and good height in the engine room.
The ventilation of the stokehole is much aided by
four pipes of about two feet diameter each, which
lead to the upper deck. The mode of ventilation
is that invented by Mr. Baker, chief engineer at
Chatham, and consists of a downcast shaft into the
engine-room, and an upcast from the stokehole, by
which there is a full supply of air in both places,
and a thorough draught to the furnaces. The Gib-
raltar has three donkey engines, two are for boiler
use exclusively, the third is for boiler uses or for
general purposes, such as pumping out the bilge
water, extinguishing fire, &c. Her stokehole is
fitted with overhead rails for the easy transit of
coal buckets, and the engine-room is supplied with
Suffield's patent indicator, for ready communica-
tion with the quarter-deck. The stokehole is 50
feet long; boilers, 42 feet. They will contain 100
tons of water. Behind them and on both sides of
the engine-room are the bunkers, which will hold
from 700 to 800 tens of coal, equal to seven or
eight days' consumption under full steam, the
quantity used in 24 hours being estimated at over
100 tons. From the centre of the engines to the
stern post, the screw shaft is 107 feet 6 inches
long; the diameter, 151 inches; in the stern tube,
17-ti inches. The Gibraltar is propelled by one
of Griffith's screws, of 19 feet diameter, with a pitch
capable of being varied from 22 to 27 feet. The
weight of the engines is 106 tons ; boilers and appa-
ratus, 206 tons 12 cwt. ; water in boilers, 118 tons ;
screw propeller and framework, 60 tons 12 cwt. ;
and of spare gear on board, 28 tons 10 cwt. ; total,
619 tons 14 cwt.
The Hussar, lately employed as a receiving-hulk
at Chatham harbour, having had the necessary
alterations and repairs effected to adapt her for a
target ship, has been put out of No. 2 dock at
Chatham. The second dock being now empty, pre-
parations will be commenced for laying down the
Achilles, previous to which, however, the present
caisson at the entrance to the dock will require to
be removed and a cofferdam erected in its place, by
which an additional length of nearly 30 feet will be
gained, thus giving a length of dock of nearly 400
feet for the new ship. Considerable quantities of
the heaviest portions of the beams and other parts
of the vessel still continue to arrive at the dockyard
from the iron companies who have entered into
contracts with the Admiralty for supplying them.
Her Majesty's iron paddlewheel steaaivessel
Weser, commissioned by Commander A. Johnstone
for the survey of the mouths of the Danube, in the
Black Sea, was yesterday undocked at Woolwich ;
and the screw steamsloop Star, built at Millwall,
was docked in her place, to be coppered.
The Pluto, 4, paddlewheel steamtug, 100 horse
power, in No. 4 dock at her Majesty's dockyard,
Sheerness, is being broken up. Forty shipwrights
are employed in carrying out the order, which is
to be completed within nine days, including the
clearing away of the timber.
The Hasty, 60, gunboat, and the Griper, 60, gun-
boat, at sheerness, are ordered to be fitted for the
first class steam reserve.
Yesterday Vice-Admiral W. J. Hope Johnstone
proceeded in the Wildfire, paddlewheel steamer, 76
horse power, to Chatham, for the purpose of inspect-
ing the /Etna and the Thunderbolt, previous to their
being removed into the Thames, to act as coast and
river defences. A further ipspection will shortly
take place, for the purpose of determining the
locality they are to occupy.
The following appointments were made yester-
day at the Admiralty :—Edwin West, promoted
to the rank of acting chief engineer in the Jasper;
Charles I. Serjeant and Joseph Lovering, promoted
to the rank of chief engineers, and appointed to the
Asia as supernumeraries ; Frederick N. Sutton,
promoted to the rank of chief engineer in the
Vixen ; James Ward, promoted to the rank of chief
engineer in the Alert ; William M. Chambers,
first-class assistant-engineer, to the Firefly; John
Jolly, second-class assistant-engineer, to the Han-
nibal ; William Rumble, third-class assistant-engi-
neer, to the James Watt ; John Muir, third-class
assistant-engineer, to the Victor Emmanuel; Joseph
Gill, acting third-class assistant-engineer, to the
Dauntless ; Henry Bunting, acting third-class
assistant-engineer, to the Hero ; Charles J. Devon-
shire, assistant-surgeon, to the Conqueror; and F.
W. B. Praed, naval cadet, to the Ariadne.