The Sun.
London, England, 1864-04-25 00:00:00

.v_,.___,-L._._.,

iN EWs rApER
rising, turned his head and roared at th ,top 6 ;,
voice, " No." The reply had not a trace Psrlt.,„,
the impertinence was so near it that (a--; 4,131
bubbled over with noisy pleasure, and was ter I • •
tempered for the whole remainder of the evenin If" IS
there is any real wit behind it or any real power ac-
companyingit, impertinence mast, with a mixed audi-
ence, be allowed to be effective. Nor is it easy to say
what other weapon a Minister would find so easy to
his hand. Real wit is a betterdefence,but every states-
man cannot have real wit, and since the days of Sir-
Robert Peel it has been rather a scarce quality
among officials. His followers were not witty,
though there is humour in Mr. Gladstone, and a
sort of sharpness in the Duke of Newcastle. Im-
passibility is an Equally good defence, but it does
not tell much in debate except when exhibited by
a very good man indeed, and officials want a form
of retort which the country can read next dey.
Some weapon they must use to keep off the bores,
and the people with private intcreste and the mea
with crotchets, and the members of the Derby
Griffith stamp who otherwise would worry them
to death, and most of whom when smashed
wA`r an argument say, "Tie right honourable
,gentleman has stated precisely what I wanted to
elicit," and sit down as radiant as if they had 'even
applauded. A Minister to be useful must be dan-
gerous, and if he can only be so by being imperti-
Lent he cannot be said to be very blameable. A
porcupine is not a nice beast, but still one does not
condemn his use of his quills as in any way im-
moral, and if members will tease people like Sir
Charles Wood or Mr. Layard, why, they know
what to expect.

„” ~-,~~

Naval and Military Intelligence.
- 4.-

THE NAVY.

The official trial of the double-screw steam launch,
which has been constructed and fitted at Chatham
Dockyard, as a tender for her Majesty's screw
steamer Bombay, flagship of Rear-Admiral the
Hon. C. G. J. B. Elliot, C,8., took place at Chatham
on Saturday. The trial shows the vast superiority
of those steamers fitted with the double-screw in
manceuvring, turning, and steering, generally, to
those furnished with the single propeller. The vessel
experimented upon is 42ft. in length, with a breadth
of beam of lift., and she has been constructed en-
tirely under the supervision of the dockyard officials.
Her engines have been manufactured by Messrs.
John Penn and Sons. They are nominally of 3
horse power, but being on the highspressure prin-
ciple they can be worked up to ten times that power.
The entire machinery occupies a space of 6ft. by 4ft.,
and the engines are so constructed that the whole
machinery can be bodily lifted out of the launch and
placed on the deck of the vessel to which she is at•
tached. The weight of the whole is 3 tons 17cwt.
2qrs. 201 b. There are four cylinders, each with a
diameter of 4in., and a length of stroke of 6in. The
connecting rod is 12in. in length, and the diameter
11; the piston rod is Zia. The diameter of the
crank axles is llin„ and the diameter of the screw
shaft the same. The :screw propeller is 31ft. in
length. The fire-grate is 2ft. by 2ft. and the length
of each of the boiler tubes, of which there are 19,
3ft. 3in., and their external diameter 21in. The
total fire-bar surface is sft. ; surface of flue, 21ft. ;
and surface of tubes, 40ft. ; the total heating sur-
face is 61ft. The two screws are 4-bladed, and have
a diameter of 2ft., the set of the pitch being 3ft.
41in. Each screw is driven by its own indepen-
dent shafting, which thus enables both to be worked
in contrary directions. The quantity of coals on
board was 13 cwt. At starting the draught of
water, both fore and aft, was 2ft. 6in. From the
above figures it will be seen that the engines are
probably the smallest ever supplied to one of her
Majesty's Tussle, nevertheless the results achieved
were somewhat astonishing, and appeared to take
all the spectators by surprise. At 10 o'clock the
screw launch steamed from the dockyard pier,
having on board Captain Stewart, C. 8., superin-
tendent of the dockyard; Capt. Colin Campbell, of
the Bombay ; Captain Stokes, Queen's harbour.
master ; Mr. Thornton and Mr. Hutchens, master-
shipwrights, and others of the officials. The engines
were in charge of Mr. Wiggell, from:Messrs. Penn's
establishment, who superintended their working.
Prior to the launch undergoing the most impor-
tant portion of her day's trials Captain Stewart
directed her to be taken to the most crowded
portion of the harbour, in order to test her mar ceuv-
ring capabilities in and out among the vessels,
boats, and other craft about the dockyard. At this
time there was a pressure of steam of upwards of
GOlb, and the screws each making upwards of 200
revolutions per minute. Before she had been out
any great distance it soon became evident that the
twin-screw principle enabled a vessel to be almost
independent of her rudder. Acting upon this Capt.
Stewart boldly directed the tiller of the rudder to
be removed, and henceforward the vessel was steered
solely by her screws. With a strong flood tide
running, the vessel was manceavred by means of
her screws with as much ease as when her rudder
was brought into use, and, indeed, the remarkable
ease with whioh she was turned round boats, buoys,
and other objects pointed out by Capt. Stewart, as
well as the surprising steaming powers of the minia-
ture craft, elicited the admiration no less than the
astonishment of all on board, as well as of the pera
sons who watched her progress from the dockyard
and pier. After fully demonstrating to the officials
the steaming and steering capacities of the screw
launch she went alongside the dockyard, where some
slight alterations were effected in the machinery,
after which the miniature vessel's head was turned
down the harbour, and a run taken towards the
Nore, during which numerous experiments were
made in steering the launch solely by means of her
screws, with the most complete success. The time
occupied in the run from Chatham Dockyard to the
Camber was two hours, which would give an ave-
rage speed of rather over six knots per hour. The
boat was also tried in making circles, when with
the port screw going ahead at fall speed and
the starboard screw working astern the circles
were made as nearly as possible on a pivot,
the average time occupied being 1.247 of a
minute with the engines making 310 revolutions
per minute. During the run to and from the Nora
the engines worked with the utmost freedom and
regularity, the boilers giving a pressure of 601 b. of
steam, the average number of revolutions of the
screws being 320 per minute. Altogether, the trials
were deemed a complete success as establishing the
superiority of the double screw principle:
The Geyser, 6, paddle, Commander Thrupp, ar-
rived at Spithead yesterday, fromDevonport, with
men paid off from the Nilo.