The Sun.
London, England, 1863-11-09 00:00:00

THE NAVY.

The screw launch Experiment, fitted with twin screws
driven by double cylinder engines of 3-horse collective power
(nominal), made her second official trial at Portsmouth, on
Saturday, under the supervision of Commander Brett, of
her Majesty's ship Asia, the trial being conducted by Mr.
J, Ward, assistant to the chief engineer of Portsmouth
dockyard, and Mr. G. Murdoch, inspector of machinery
afloat. The wind was from the eastward, raising a slight
swell on the water that was rather against the chance of
the vessel exhibiting her hightest possible rate of speed.
A reference to the figures appended will, however, show
that the speed attained on the present trial was rather in
excess of that on the first trial ; but, as a higher and more
uniform pressure of steam was Maintained on the present
than on the previous trial, there is no doubt that had
the conditions of fence of wind— and smoothness of
water been equal, the experiments would have realised a
speed of seven knots. On reaching the measured mile in
Stokes-bay four runs were made, with both propellers
working, with the following results :-Ist run 6'394 knots.
steam pressure '6olbs.; 2d, 71.14 knots, steam pressure,
621b5.; 3d, 6,428 knots, steam pressure 621bs. ; 4th, 7.128
knots, steam pressure 641bs. The mean speed of the four
runs was 6780 knots. The evolutions of the engines ranged
from 302 to 304. Two runs were made with one propeller
(the port) only working, the results being :-Ist run, 4'551
knots, steam pressure 601bs. ; 2cl, 4 675 knots, steam pres-
sure 601bs. The mean speed was 4613 knots, the revolu-
tion of engines ranged from 320 to 360. These resultB
being found sufficiently concluiivse as to the boat's speed',
using both or only one propeller, she was next tested in
making circles, which were completed as follows :—With
both propellers going ahead—Half circle to starboard, 35
sec. ; to port, 32 sec. ; full circle, to starboard, 1 min. 8
sac. ;to port, 1 min. 8 sec. The diameter of the circle was
nearly three times the boat's length. With one propeller
driving ahead and the other astern, the following results
were obtained, the boat, as will be anticipated from previous
trials with twin screw vessels when driving their screws in
opposite directions, revolving after the fashion of a turn-
table, but with a spiral motion astern :—Half circle, to
starboard, 35 sec.; to port, 32 sec:; full circle to starboard,
1 min. 57 sec. ;to port, 1 min. 37 sec. It will be seen that
in twisting the boat round a circle the diameter of which is
her own length, a somewhat longer time is occupied than
in going round one three times her length. In the one in-
stance speed is sacrificed to the circle's diameter, and in the
other instance it is the reverse. The power of steering the
boat by the screws alone was next tested, and was at-
tended with the same certain result which has always
attended a similar experiment with twin screws. In
fact the boat, it was found, could be steered by her
screws alone with a precision and ease equal, if not
superior, to what would have attended the uee of her
rudder. This exactness or ease may not probably be found so
readily attainable in a vessel of large tonnage, but there can
be no possible doubt that a vessel of any tonnage may be
eteered With perfect safety in the Thames, or any other
river having a sufficient depth of water, by her screws alone
and without any rudder. Some further trials will be made
at Portsmouth with the Experiment, it being intended to
try her with her masts and sail on board, and her bow gun
and carriage fixed in their positions, and with her other
stores on board. It is very likely that this last trial will not
be attended with the most satisfactory results, as the boat
would then be too deep in the water either for speed or sea-
worthiness, It is the intention of the Admiralty to fit all
launches of first-class ships in the same manner in which
the Experiment is fitted, and simply as steam-tenders or
tow-boats they will be invaluable to the ship they belong
to. Towing the ship's boats, with their respective
crews on board, or any armed expedition, with her own
crew as riflemen, but with no big gun, the steam launch
would move along at a good speed ; but the load of a heavy
gun and its ammunition and masts and sails would so reduce
her speed as to render her all but useless as a towing vessel
to the other boats of the ship. With a ship's launch steam •
ing up an enemy's river with the other boats of the ship in
tow the crews of the latter would not expose themselves in
rowing, and, in addition, could bring their rifles to bear on
the river's banks from under the cover of their boats' bul-
warks, if not engaged in working the boat's gun. The Rus-
sians have for some time supplied single screw steam
launches to their ships on foreign service, and use them
chiefly as a means of transport, Her Majesty's ship Warrior
will, it is expected, be the first vessel in the British Navy
that will be supplied with one of the twin screw launches.
The Orontes, screw iron troopship, Capt. W. H. Hire,
arrived at,Spithead, late on Friday evening, from Malta and
Gibraltar. The military invalids were transferred front the
ship en baturday to Natley Hospital, and the time-expired
men, women, and children, insane men and priecners, to
the depots of their regiments, &c. The naval invalids were
transferred to her Majesty's ship Victory, and the Royal
and Naval Hospital at Hasler. Two warders and 32 con-
victs (the latter are tickets-of-leave), who also came from
Gibraltar in the ship, were transferred to the convict prison
at Portsea. Some 700 tons of old stores and a large quantity
of condemned powder has been sent to England in the ship
rom Malta and Gibraltar. The Orontes sailed from Malta
on the 31st ult., leaving at anchor there her Majesty's ship s
Hydra, Procris, and Redpole. The Malacca, 20, screw'
sailed from the Rock for England on the 20th ult. The Gib-
raltar, screw, liner, Capt. Prevost, sailed for Malta on the
31st ult. The Racoon, 20, screw, Capt, Count Gleichen, was
lying at Malaga. At Malta there was dullness of trade, and
consequent grumbling ashore, owing to the lengthened ab-
sence of the fleet at the Pirmus. Since leaving England the
Orontes has done very efficient service in the Mediterranean
in the exchange of regiments between Malta and Gibraltar,
and in the performance of which duty the conduct and at-
tention to the wants of their military passengers of Capt.
Hire and his officers are spoken of in very high terms. It
is, however, stated that although the Orontes was designed
and constructed for an improved Himalaya, she is, in fact,
very far from being even the equal of that vessel. Her ma-
chinery is of insufficient power, and she can with difficulty
average 10 knots. Her steering power is also defective, her
wheel requiring considerable alterations. At present it
takes six men in ordinary weather to steer her. She is an
excellent sea boat and remarkably easy in rough weather.
Her immediate requirements (to make her approach the
Himalaya in comfort to her passengers and speed) are, a
poop on the upper deck, and the present cabin space on the
main deck added to the troop berthing ; some alterations to
her machinery, and additional boiler space. It will take
about three weeks to make good her ordinary defects.
The crew of the screw steamship Desperate, 8, were paid
off on Saturday at Devonport, in the presence of Admiral.
Superintendent Symonds. The sloop will be placed in the
3d division of the Steam Reserve in Hamoaze.

The paddlewheel steam-tender Sprightly, from Porte.
mouth, arrived on Saturday at Plymouth, with supernume-
raries for the Royal Adelaide.

The Emerald, 35, screw steam-frigate, 2,913 tons, 600-
horse power, Capt. A. Cumming, which recently formed one
of the Channel squadron, was paid out of commission by
Capt. Charles Wise, A.D.C., Superintendent of Sheerness-
dockyard, on Saturday. On Friday the officers of the dock-
yard and Sheerness Steam Reserve inspected the vessel
and machinery, and she is to be placed in the 3d division of
the Steam Reserve.

The sailing transport Empress, belonging to Messrs.
Houlder Brothers, taken up by the War Department for
the transport of the 4th battalion Military Train to Auck-
land, New Zealand, sailed from Woolwich pier yesterday
morning, in tow of two ateamtugs as far as the Nore. The
ship's hold was stowed well up with war stores of every de-
scription, consisting of guns, trenching tools, tents, forage,
hospital comforts, and on immense number of cases filled
with saddlery, harness, &c., amounting to 100 tons mea-
surement, and 100 tons of powder and ammunition in her
magazines. A large number of sheep, pigs, and poultry
were shipped for the voyage, and a patent distilling appa-
ratus will supply 55C gallons of fresh water per day. The
married officers and a proportionate number of the men are
accompanied by their wives and families.
The following appointments were made on Saturday at
the Admiralty :—Lieut. H. R. Berners, to the Liffey; Lieut,
H. C. Onslcw, to the Tamar; Arthur Blennerhassen, mid-
shipman, to the Royalist; Jas. H. Wallis, assist•surgeon,
to the Cumberland; Arthur J. Ireland, assist.-surgeon, to
the Duke of Wellington; and George Doveson, clerk, to the
Adventure.