The Sun.
London, England, 1859-12-10 00:00:00

THE NAVI'.

The Ariadne, 26, screw frigate, Captain E. W.
Vansittart, was removed from the sheer hulk at
Chatham dockyard, and towed further down the
river to receive her Armstrong guns and her powder
on board. She is still short of her proper comple-
ment, but there is no doubt she will pick up the re-
mainder of her crew at Portsmouth, where she is to
proceed, after leaving Chatham, to await her final
orders.
The Charybdis. 21, screw corvette, was yester-
day admitted into the first dock at Chatham, to be
brought forward for the reserve service.
The Himalaya, screw troopship, Commander J.
Seccombe, will sail from Portsmouth, if possible,
on Monday next, for Halifax and the West Indies,
calling at Plymouth and Kingstown.
The crew of the Hero, 91, screw, Captain G. 11.
Seymour, was paid wages yesterday at Spithead,
and one watch granted leave ashore.
The Dryad, hulk, at Portsmouth, has been taken
into No. 1 dock at Portsmouth, to be broken up.
A series of important experiments have, during
the past 8 months, been carried out at Portsmouth
on board her Majesty's paddle steamer Wallace,
under the supervision of Mr. G. Murdock, inspec-
tor of machinery afloat at that port. The object
sought to be attained is the removal of the "scale"
generated on the surface of steam-boilers and their
tubes by other and more expeditious means than by
the present system of manual labour. The import-
ance of the subject will be fully comprehended by all
who may be in the slightest degree conversant with
steam machinery. Under the present system,
should a ship's boilers require cleaning out, or clear-
ing from scale, while on board the ship, all the
boiler doors are taken off and a number of men
sent into the boilers to clear the scale by manual
labour. By these means, with the greatest exer-
tion, and any amount of time, possibly 10 per cent.
of the scale might be removed, and with this small
improvement the engineer well knows the relief he
finds in getting steam. By the system which has
now been undergoing a long series of tests on board
the Wallace only one door of the boiler has to be
taken off to allow the introduction of the steam
pipe. The boiler to be acted upon is then filled
rapidly with superheated steam at a temperature
of 400 deg. of heat; this acting upon the saline de-
posits on the surface of the tubes, and other parts of
the boiler, expands and disengages it from the seve-
ral parts. After this the boiler is again filled with
water; and steam got up in the usual manner, and
kept up for a few hours, and on afterwards blowing
off the boilers they are found to be as free from
scale as when they were first put on board the ship.
The experiments have been highly successful. The
saving of fuel alone in our steam ships of war from
adapting this plan to their boilers will be very con-
siderable, and the whole scale may be removed
from a ship's boilers in twelve hours. A very re-
markable specimen of " scale" may be seen in the
chymical laboratory in Portsmouth dockyard,
which was removed from the boilers of her Ma-
jesty's ship Sidon, when under the command of Sir
C. Nap
perfect.
The following
impression of
scale
ehe is
following appointments wt he t o
re
mu tubes on
a de
yeyester-
day ttehre.
day at the Admiralty :—Lieut. P. Durrant, to the
Excellent ; J. H. H. Smale, first class assistant en-
gineer, to the Cumberland, for the Wrangler; M.
Hawkins an& D. Howarth, acting third class assis-
tant engineers, to the Asia ; and W. T. Dixon, pay-
master additional, to the Excellent.