The Sun.
London, England, 1862-05-19 00:00:00

THE NAVY.

' The Duke of Somerset, as First Lord of the
Admiralty, will held a levee (the last this season)
on Thursday neat, at the Admiralty, Whitehall.
Letters dated February have been received at
Ply mouth from the screw steam corvette Charybdis,
21, Capt. the Hon. George D. Keane. She was
then at Yokahamma, Japan, but in consequence of
intelligence received from England in relation to
the Trent affair was appointed to sail the next day,
the 19th, for Vancouver's Island. On board the
corvette it was supposed that her commission would
he completed on the Pacific statical, under the com-
mand of Rear-Admiral Sir 'rhos. Maitland, K.C.13,,
crew steam frigate Bacchante, 51.
The Shannon, screw frigate, Capt. -Wainwright,
resumed her experimental trials at Portsmouth on
;iaturday, steaming out of harbour at noon for the
trial ground in Stokes Bay. The screw tested on
this occasion was the double-bladed " Mangin." It
was cast in the new foundry of Portsmouth dock-
yard, but copied from the screw now in use in the
:French Imperial navy, into which it was introduced
by M. Mangin, the inventor, some few years since.
This screw was fitted to the Austerlitz and ether
French ships of war at the time the Anglo-French
fleets proceeded to the Baltic on the outbreak of
hostilities with Russia; but it never attained a re-
putation, superior, if equal, to that of our common
Admiralty pattern screw. It required a less aper-
ture, however, in ships' sterns when necessarily
lifted. Other advantages were also claimed for it
by its advocates. The weather on Saturday was in
the highest degree favourable for developing the
power of any propeller, the wind being light and
the water perfectly smooth. The draught of water
Rey the ship was within one inch of the previous day
aft, and the same forward, being 20ft. tin, aft, and
21ft. gin. forward. On clearing the harbour channel
the ship at once proceeded to the trial ground, and
hilE runs were made at the measured mile. The
time and speed were respectively—in the Ist, 5 Min.
9 sec., 11.650 knots ; in the 2d, 5 min. 36 sec., 10-714
knots; in the 3d, 4 min. 55 sec., 12.203 knots; in
the 4th, 6 min. 2 sec., 9 944 knots ; in the sth,
4 min. 36 sec., 13.043 knots; and in the 6th, 6 min.
9 sec., 9.756 knots. In the fifh and sixth runs the
number of revolutions was 531, in the other 53.
Mean speed of the whole, 11.331 knots. At the con-
clusion of the runs of the measured mile the ship
was taken off to a fitting position, and her time as-
certained in making a complete circle with the helm
to port and also to starboard, the time being taken
from the moment of giving the order. The same
number of men (five)—in fact the same men—were
at the wheel as were there on the previous day. The
helm was first put hard:aport, and the rudder was
hove over to an angle of 131 deg. in 28 seconds. The
circle was completed in 7 minutes 14 seconds. The
helm was next put to starboard, the rudder was
hove over to an angle of 151 deg. in 30 seconds, and
tale circle completed in 7 minutes 1 second. The
engines during the time of making both circles ave-
raged 52 revolutions. It will be seen, therefore, by
comparison with the trial of the Admiralty pattern,
or common screw, of the previous day, that the
Mangin screw on Saturday obtained a slight advan.
tage, but very slight, certainly, in point of speed,
and that the ship also came round in less time than
she did on the preceding trial. Both these appa-
rently slight advantages were full accounted for by
the peculiarly favourable conditions of wind and
weather under which the Mangin screw was tried.
On the other hand, the Mangin communicated to
the ship a far greater vibratory motion than did the
common screw, had an unusually violent beat in its
revolutions through the water, and raised a column
of water beyond what is usual in the screw well.
The trials will be again resumed with a fresh pro-
peller to-day.
Some interesting firing with the 68-pounder
smooth-bore took place on Thursday, Friday, and
Saturday, from the Stork gunboat, at armour plates
on the side of the Sultan, target ship, at Ports-
mouth. With one exception, no armour plates pre-
viously tested at Portsmouth, whether experimen-
tally as targets, or merely for testing purposes,
have exceeded 4iin. The exception alluded to was
in the instance of Mr. Jones's angulated target,
one-half of which was plated with 51in. plates.
The plates lust fired at in Portsmouth harbour were
all 51in., and comprised one plate from the Mersey
Steel and Iron Works, 15ft. long and 3ft. 4in. in
breadth; and three plates from the Thames Ship-
building Company ; Messrs. Brown, Atlas Works,
Sheffield ; and Messrs. Beale, of Parkgate Works,
Yorkshire ; each plate being 6ft. in length and 3ft.
Sin. in breadth. 200 yards was the distance, and
cast-iron shot was used with 161 b. of powder. The
Mersey plate received 14 shots, Brown's and Beale's
9 each, and the Thames Iron Company's 10. The
timber backing, or ship's side, behind the last three
was not penetrated. All the plates were, of course,
broken, but all were of a superior quality, and all
proved by themanner in which they stood the pound-
ing of the 68 pounder that the additional inch of
iron added to their resisting power sufficiently to
compensate for the additional weight of armour,
about 401 b. per square foot. There is one other im-
portant feature worthy of notice. The latest trials
of armour plates have satisfactorily demonstrated
that great improvement has been made in the all-
important matter of welding rolled plates within
the last 12 months, The greatest and most active
agent in the destruction of all armour plates, how-
ever perfectly they may be manufactured, or how-
ever costly the material, are the bolts by which they
are at present fastened to their ships' sides. All
fractures from sound plates, on being struck by shot,
spring from or to a bolt hole, and a fracture ones
started in a plate, the destruction of the latter be-
comes merely a question of time, dependent upon
the quality of the iron used in its manufacture.
The Imperial Russian frigate Oleg sailed from
the Motherbank on Saturday evening for Copen-
hagen and Cronstadt.
The Cormorant, 4, 690 tons, 200 horse power, and
the Racehorse, 4, 200 horse power, both attached to
the Chatham steam reserve, are to be immediately
got ready for service on the China station.
The screw steamship Sanspareil, 80, Capt. Le G.
Bowyear, one of the Mexican expedition, which
left Vera Cruz on March 15 and Bermuda April 24,
arrived in Plymouth Sound on Saturday. She
brings home about 350 rank and file of Royal
Marines, under the command of Lieut.-Col. Samuel
Netterville Lowder, of the Plymouth division,—
viz., belonging to the Plymouth division, 200 rank
and file and the following officers :—Capts. Elliott,
West, and Naylor; First Lieuts. Nurse, Herlut,
Smith, Bouchier, and Westby ; and Second Lieuts.
Brea and Harrison ; belonging to the Portsmouth
division, 40 rank and file, under Capt. J. R. Lloyd,
and 28 Royal Marine Artillery, under First Lieut.
Poore; belonging to the Chatham division, 20 rank
and file, with Second Lieut. Menzies and Paymas-
ter Cooper; and belonging to the Woolwich division,
40 rank and file, under Capt. J. B. Seymour.
I hiring the absence of the expeditionary force 39
marines have died from fever and dysentery. Those
now returned appear to have been much debilitated
ev the climate. The Eastern division of Royal
Marines will proceed to-day, in
the paddle-wheel
steam vessels Geyser and Virago, to Portsmouth,
Chatham, -and Woolwich. The Sanspareil left on
the Mexican coast Her Msjesty's screw steami n
Mersey, 40, Capt. Henry Caldwell, C.B. , . gate
the steam
corvette Challenger, 22, Capt. John J. Kennedy,
C.B. ; the paddle-wheel steam sloop Barraconta, 6,
Commander G. J. Malcolm ; and the screw steam
gun-vessel Plover, 5, Commander the Hon. A. L.
Corry ; six French ships of war, including one line_
of-battle ship, three frigates, and three steamers;
and six Spanish ships—viz., three frigates and
three steamers. At Bermuda the screw steamship
Capt. E. K. Barnard, flag of Rear-Admiral Sir
_Alexander Milne, K.C.8.; the screw steamship
Donegal, 99, Capt. Sherard Osborn (which is ordered
home) ; the screw steamship Agamemnon, 89, Capt.
Thomas Rope ; the screw steamship Hero, 89, Capt.
A. P. Ryder ; the screw steam frigate Orlando, 50,
Capt. Francis Scott, C.B ;
the screw steam frigate
Melpomene, 51, Capt. Charles J. F. Swart; the
paddlewheel steam sloop Spiteful, 6, Commander
W. C. F. Wilson; Paddle-wheel steam sloop Hydra,
6, Capt. R. V. Hamilton, and the steam gunvessel
Landrail, 5, Commander T. iiM. Martin. The
crews of all the ships on the Mexican coast and
Bermuda were in a healthy state. The Sanspareil