The Sun.
London, England, 1862-11-25 00:00:00

11IE NAVY.

Letters received yesterday by our Chatham cor-
respondent, dated " Fortress Monroe, Virginia, Nov.
9," announcing the departure from that place, on
the 28th ult., of her Majesty's screw steamers Cad-
mus, 21, 400-horse power, and Racer, 11, 150-
horse power, the latter on her way to England,
calling at Halifax, to be put out of commission.
The Cadmus was absent on a cruise till the 2d of
November, when she returned to Fortress Monroe,
at which was also lying the screw sloop Petrel, 11,
150 horse power. Gen. Dix, Governor of Fortress
Monroe, accompanied by his staff, visited the Cad-
mus and Petrel on the 3d inst. At noon on the 9th
inst. both ships were dressed in colours and a royal
salute fired by each in honour of his Royal High-
ness the Prince of Wales arriving at age. The salutes
were returned by the guns from the fort.
An Admiralty order has been received at Chatham
announcing that the usual examination of candidates
for apprenticeship by the Civil Service Commis-
sioners will not take place in the month of January
next, as it is not intended to enter any apprentices
in the dockyard during the next half-year.

Yesterday preparations were commenced in No.
4 dock, at Chatham, for the reception of the
paddlewheel steamer Promethus, 5, 200 horse
power, which is to undergo a thorough overhaul
and repair, her repairs being rendered necessary
in consequence of the length of time she was sta-
tioned on the coast of Africa.

The last advices from Australia report the fol-
lowing ships on that station :—The Fawn, 17, Capt.
Cator, at Hobart Town; the Harrier, 17, Capt. Sir
Malcolm M'Oregor, at New Zealand ; the Miranda,
14, Capt. Jenkins, at Melbourne; the Pioneer, 6,
Capt. Reilly, on a cruise to the northward; and the
Orpheus, 21, Commodore Burnett, at Sydney.
The Lily, 4, screw steam gunvessel, 702 tons,
200-horse power, was yesterday taken out of Sheer-
ness dockyard on trial of her machinery, which has
been undergoing some slight alteration. Com-
mander H. Harvey had charge of the vessel, her
engines being under the superintendence of Mr.
Rumble, Inspector of Machinery Afloat, and Mr.
Townsend. She sailed round the Mouse Light and
back, every thing working in a most satisfactory
manner. The Lily will be taken out on her trial
trip on Thursday next, previously to proceeding to
her destination.

About two months since there appeared in The
Sun an account of an experiment tried in Plymouth
Sound on a merchant steamer, the Volunteer, fitted
with Mr.Mulley's newly-invented auxiliary rudder.
That experiment was so successful that the Lords
of the Admiralty shortly afterwards appropriated
the screw steam Cordelia, 11 guns, of 579 tons and
150-horse power, to the use of the inventor, and she
was accordingly fitted with the auxiliary rudder
under the port quarter. It consisted of nine bars of
American elm 6 inches wide by 4 inches thick, the
area being 9 feet long by 41 feet wide. The auxi-
liary was made of bar 3 to fall somewhat into the
shape of the quarter, and the entire frame was
hinged at the fore end, and was opened out aft by
Byes worked from the deck when required for use.
So equipped, she went into the Sound yesterday,
when a trial took place, under the superintendence
of Capt. Astley C. Key, C. 8., of the guardahip of
steam reserve Indus ; Mr. ['Nike, master builder, De-
vonport dockyard ; and Commander Brown, master
attendant, and the inventor. The result was most un-
expected. The ship's helm being put hard to starboard,
a complete revolution, without the interference of
the auxiliary, was made in 6 min. 26 sec. The
auxiliary, tried alone, was found not in any degree
to affect the ship's course ; this was attributed, in
some measure, to the fact the Cordelia is supplied
with a left-handed screw. The helm and the auxi-
liary being both put to starboard, the circuit occu-
pied 7 min. 37 sec., the auxiliary thus retarding in-
stead of assisting the revolution. These experi-
ments were repeated under various conditions, with
a uniform result. The quickest revolution (4 min.
50 sec.) was accomplished when the rudder was
placed in opposition to the auxiliary. The longe,t
(7 min. 37 sec.) was when the auxiliary power was
added to the action of the ordinary helm. These
results appeared to be inexplicable to all on board
the Cordelia.