The Sun.
London, England, 1862-03-01 00:00:00

THE TRIAL OF TILE DEFENCE.

This ship, of 600-horse power (nominal), 3,668
tons, and mounting 18 guns, commanded by Capt.
Richard A, Powell, 0.13., made her official trial
of speed at the measured mile in Stokes nay; Ports-
mouth, yesterday. The ship was cast off from the
dockyard at 9 45 a.m,, and left the harbour under
half steam, in charge of Capt. H. Broadhead, com-
manding her Majesty's ship Asia and the Steam
Reserve at the port ; Mr. Murdoch, inspector of
machinery afloat, and Mr. Miller, assistant engineer
to her Majesty's dockyard, superintending the trial
on behalf of the Admiralty; the machinery being
in charge of Mr. Halliday, representing the con-
tractors, Messrs. Penn and Son. A strong breeze,
at a force from 5 to 6, frcm E.N.E. was blowing as
the ship left the harbour at half speed, and a turn
was taken to the eastward of the anchorage to give
time for consultation with regard to the weather.
The breeze, however, increased rather than lessened
in force, and it was determined at all hazards to put
the vessel on the trial ground, as, should the trial
prove unsatisfactory, as might naturally be expected
from the state of the weather, it could be repeated
on a more favourable occasion. The result, how-
ever, will show that the speed of the ship under
steam is perfectly satisfactory. At the same time,
it must be remembered that the Defence, like the
Warrior, is the pioneer of her class, and therefore
both ships, so far as relates to comparative merits,
should be tried under precisely similar circum-
stances. Those circumstances are, that the War-
rior had nearly a calm and perfectly smooth water
in her trial. The Defence, on the contrary, had a
heavy breeze from E.N.E., and troubled water.
Under these circumstances the trial was commenced
and concluded, the pilotage of the ship being in
the hands of Mr. Jones, the veteran Queen's pilot
of the port, than whom, it is allowed by all, none
more efficient at his duties can be found. The fol-
lowing are the six runs made, and their results :-
Ist Run.— Mean time, 3 min. 47 sec. ; speed in
knots, 12.543; revolutions of engines, 671. 2d Run.
—Mean time, 6 min. 15 sec.; speed in knot, 9.600 ;
revolutions of engines, 651. 3d Run.—Mean time,
4 min. 33 sec.; speed in knots, 13.186 ; revo-
lutions of engines, 671. 4th Run,—Mean
time, 6 min; '24 sec. ; speed in knots, 9.375 ;
revolutions of engines, 68. sth Run.—Mean

time, 4 min. 25 sec. ; speed in knots, 13 584 ; re-
volutions of engines, 67. 6th Run.—Mean time,
6 min. 24 sec. ; speed in knots, 9.375 ; revolutions
of engines, 68. First means :-11.071, i 1.393,
11.282, 11480, 11.479. Second means:-11.232,
11.338, 11.381, 11.480. True mean speed, in knots,
11.357.
At the close of the runs at the measured mile the
ship was laid fair for Spithead, and, when in a fit
position, the helm was put hard a-port and a com-
plete circle made in 6 minutes 30 seconds, and, with
the helm the contrary way, in 7 minutes 6 seconds,
the time being taken in both instances not before
the ship felt her helm. The speed of the ship while
making the circles, with the helm hard over, was,
9 knots. The draught of water of the ship was—
aft, 25ft 4in ; forward, 24ft 4in. The pressure of
steam was 201 b ; vacuum, 24in. The propeller was
an improved Griffiths, with a diameter of 18ft and
a pitch of 21ft. The engines were stopped dead
from the time of moving the engine-room telegraph
in 6 seconds, started ahead again in 7 seconds, and
turned from that position astern in 13 seconds. In
turning at the measured mile, the position of the
ship, as taken from the shore in Stokes Bay, was
altered as follows :—From the time the masts were
in one, the ship's stern being to the shore, until
they were in the opposite pcsition, was 21 minutes,
and from the time they were in one from aft for-
ward (in the first-named position) until they were
fairly broadside on with the shore was 1 minute 40
seconds.

At the conclusion of the experiments the ship's
head was laid for the harbour, and in passing along
the harbour channel, in line with Southsea beach,
an accident occurred which might have been, but
fortunately was not, attended with very serious
consequences. It had been observed, with no small
alarm, that on the ship completing her first run at
the mile, in taking a sweep to the eastward along
the edge of the Sturbridge shoal to bring her head
round again for a second run to the westward,
she for some time took no notice whatever of
her helm after being put hard over, and ran in
dangerous vicinity to shoal water; but just in
time she came up to her helm, and escaped, most
probably, a disaster. The same uncertainty was
found in putting her at the circle, and, in fact, her
time in completing the circle was not taken until
she fully felt and answered her helm. In entering
the harbour channel, in line with the beach of