The Sun.
London, England, 1864-12-15 00:00:00

The Achilles.

The iron frigate Achilles, 20 guns, 6,079 tens,
1,250 horse power of engines, Capt. Vaasittart, com-
menced her official trials in her sea-going trim yes.
terday, at Portsmouth, with her runs over the trial
ground at the measured mile in Stokes-bay, with
full boiler power, and in making her circles—also
under full power. A gunboat left the harbour at
8 30 a.m., for Spithead, with the officials oa board
to conduct the trial, the latter comprising Comman-
der Brett, of her Majesty's ship Asia; Messrs Ward
and Murdock, of the Steam Factory and Steam Re-
serve Departments; Messrs Brain and Elliott,
Assistant Master Shipwrights, &c. On the officials
reaching the ship she at once steamed out from the
anchorage to clear her fires in readiness to enter on
the mile. It was nearly 11 a.m., however, before
the ship commenced her first run, owing to a diffi-
culty experienced with her coals. The ship's draught
of water was 25ft 6in forward, and 26ft 10in aft.
She was not quite complete in ail her atorea, though
the deficiency was but trifling, and she had 560 tons
of coal in her bunkers, when she could have stowed
769 tons. The wind was moderately fresh, about 4
in strength, from E.N.E., with smooth water. The
engines drive a four blade Mangin screw, the blades
being fired at equidistant intervals round the boss
on the shafting, the diameter of the screw being 24ft
6in and its pitch 26f: Sin. The engines are pre.
cisely the same power as those of the Warrior-
-1,250 horses—made from the same patterns and by
the same makers, Messrs Penn. The ship's midship
section is stated to be precisely the same as the
Warrior's; in fact, she is a second Warrior, both in
hull and engines, with the single but important
exception that she is an Admiralty ,t im-
provement" on the Warrior, inasmuch that
the Achilles has had her bilges pulled out a little,
her floor also slightly lengthened forward, her arm
mour plating carried up to her main deck above the
water line round her bow and stern, her hull being
also minus figurehead and quarter galleries, and four
masts put into her in lieu of the ordinary three.
With these supposed improvements it might ream
sonably have been expected that the Achilles would
yesterday have beaten the Warrior in point of speed
at the measured mile, but the contrary was the re-
sult, and the Warrior still retains her proud position
as the fleetest ship under steam in her Majesty's
navy. The following are the results of the Achil-
les' run yesterday :

No. of - Time. Speed of ship. Steam. Vacuum. Rev. of
Run. M. s. Knots. Lb. Inches. Engines.
1 4 13 14.220 22i 26 49i

2 5 6 11.761 23

25 49

3 4 3 14 815 231 251 491
4 5 8 11.668 22 26 481
6 356 15.264 23 251 491
6 5.16 11.392 23/ 25 50
7 3 50 15.652 23 25 50
8 519 11.285 25 26 5)

Throwing the two first runs out of calcula•
tion, the remaining six give the ship a speed of
knots of 13 419. To appreciate the exact value of
this result we must refer to the ship's trial at light
draught off the Maplin Sands in April last, and the
Warrior's trial in her seagoing trim in Oct., 1861.
The Achilles on her light trial drew 22ft Gin.
of water forward, and 23ft 9in aft, or a mean draught
of 23ft 2in, and she attained a mean speed in her
six runs over the measured mile of .14 357 knots.
The Warrior, in her deep seagoing trim in October,
1861, drew 25ft Gin of water forward, and 26ft Sin
aft, giving a mean draught of 25ft 111 in, end she
attained a mean speed in her six runs over the mea.
eared mile of 14.354 knots. The Achilles yesterday
had thus a mean draught of water of 3ft in excess
of her draught on her light draught trial in April
last, and a mean draught of 21in in excess of that of
the Warrior in October, 1861. Two and a half
inches mean excess of immersion must necessarily
have its due effect on a ship's speed at the measured
mile ; but it will not account for the knot difference
in speed, for it cannot be really called less, between
the Achilles and the Warrior, and the cause must,
therefore, be looked for elsewhere. This cause may
not possibly be found attached to any one point of
difference between the two ships, but rather to
several causes, the most prominent of which are—
the substitution of a four-bladed " Mangin'' screw
in the Achilles for the two-bladed " Griffiths' of
the Wm rior, and the extra weight imposed on the
bows of the Aehilles by the forward, or bow mast
(as the ship has four masts there is a difficulty in
naming them, SO as to be understood clearly by the
reader), and her topgallant forecastle. A ship can-
not be loaded with impunity over its bows when
sent on a trial of speed over the measured mile
any more than a racehorse could be sent over the
course at Newmarket with a heavy weight sus-
pended round its neck. The Achilles has, however,
been thus unwisely weighted, and in her trial of
yesterday she paid the anticipated, and, indeed, un-
avoidable, penalty in a commensurate loss of speed,
if we attribute the greater portion of her loss to
this cause and not to the change of screw alone,
which may be fairly done. After the runs had
been concluded over the trial ground in Stokes-
bay, the ship was tested in her turning powers in
making circles with the following results
To Port.—Half circle made in 4min. 21sec. ; full
circle, Bmin. 36sec. ; angle of rudder, 25.5 ; turns of
wheel, 3; men at wheel, 21 ; time in getting up
helm, lmin. 4sec.; revolutions of engines, 47.
To Starboard.—Half circle made in 4mia. 4sec. ;
full circle, 7min. 56sec. ; angle of rudder, 25'5;
turns of wheel, 3 ; men at wheel, 18 ; time in get•
ting, up helm, lmin. 40sec.; revolutions of engines,
44.

The next step and the final experiment of the
day, was to teat the engines in their working to
signal, which give the following satisfactory
results:—
Engines stopped from time of moving telegraph
on the quarterdeck bridge in 19sec., started ahead
in 6sec., and from that position started astern in 16
secs. The engines made 13.250 revolutions during
the day, and their indicated power during the runs
over the measured mile was, as near as possible,
5,000 horse. The temperatures taken during the
first and last runs were—
When On Engine Fore Aft
taken. deck. room. stokehole. sto kehole.
Ist run 48 70 84 63 94 92 114 116 125 118
6th run 48 74 88 66 9) 104 118 123 130 128
Of the engines no particular description need be

given, as they are counterparts of those of the
Warrior, and they did their work quite as satisfac-
torily yesterday as the Warrior's did on the day of
her trial. More than this cannot be said in their
favour, for the simple fact that it would be impos
siblo to award them a higher weed of praise. They
were in sole charge throughout the day of the chief
engineer of the ship, Mr. J. Leys. Messrs. Penn
were represented on board by Mr. Matthews, a
member of the firm. As regards the ship herself
and her general appearance, at a distance she looks
with her four masts a very bad imitation of the
Great Eastern, and this appearance will not be im-
proved until the bow mast is taken out of her end
her foremast proper is removed some 15 or 20ft. for--
ward of its present position. The forward or bow-
mast, with its square rig, is not nnly an eyesore to
the ehip's general appearance and retards her speed
under steam, as was proved in yesterday's trial, but
it is also all but useless when the ship is under sail,
for if the wind is well aft the beam its canvas is not
wanted, and if the wind is at all short, or on the
bow, its canvas cannot be made use of, for its yards
cannot be braced up sharp, owing to the lead of the
stays and other gear. This mlitake in the ehip's rig,