The Liverpool Standard and General Commercial Advertiser.
Liverpool, Merseyside, England, 1843-05-05 00:00:00

THE SCREW PROPELLER.

A small iron steam vessel has for some time been causing
considerable interest on the river, and may be considered a
subject of great public importance from the improvement
which it exhibits over the present mode of applying steam
power for the propulsion of vessels. When we look at the
ordinary paddle wheels, it is matter of surprise that they can
be secured from injury when the steamer is labouring in a
heavy sea, or that the vessel can be driven forward against
the wind with such incumbrances. It is somewhat surpris-
ing also that seamen, with all their prejudices, could ever be
reconciled sufficiently to such cumbersome appendages, when
the predilection of a seaman for a snug vessel is so proverbial.
From the specimen we have lately seen, and are about to de-
scribe, we foretell the speedy removal of those unsightly ma-
chines, which will probably be looked back upon as nothing
better than a pair of mill wheels suspended over the sides of
the vessel. . . . _

When we first saw the small vessel which is the subject of
this notice, skimming almost like magic on the Mersey, we
were disposed to cry out in a similar strain with a gentleman
who also witnessed her performance for the first time, " Good
bye to paddle wheels."
It will be very generally known that the screw propeller
has for some time excited considerable attention, from its
causing the removal of paddle-wheels and boxes ; but it has
made but little progress in actual practice from two causes—
one being the supposition that it could never be made so
efficient in propelling as the paddle-wheel—and the other
that, to obtain sufficient velocity it was necessary that it
should make more revolutions than the engines which
worked it, requiring the intervention of spur wheels, or
straps arid pulleys. This small steam-vessel, which was
built by Messrs. Mather, Dixon and Grantham, of this town,
however, proves very clearly that such doubts aro fallacious.
The engines are applied direct to the shaft to which the
screw is attached, and no spur wheels are required to obtain
the necessary speed ; and the makers have assured us that
this principle can be carried out in the largest vessels without
employing any means that practice has not already success-
fully established in the use of paddles on the old system.
That high velocities can be attained is shewn by this vessel,
which has now beaten every steamer on the Mersey, and this
with an expenditure of fuel not much exceeding one cwt. per
hour. _

We ourselves witnessed a race between her and the go-
vernment tender, in which the latter was certainly left be.
hind ; this is remarkable, as the tender is of great length,
and we are informed has a much greater power in proportion
to her sectional displacement.
_ . . .

Another proof of the value of these improvements is shown
in the fact, that the relative speed of the vessel and the screw
are as 93 to 100, while with the paddle wheel the proportion
is generally as 70 to 100, showing a saving of upwards of 20
per cent., or, in other words, that an engine of 80 horses'
power, with a screw, will drive a vessel as fast in smooth
water as one of 100 horses', with paddle wheels. But this is
not all; every one knows the loss with paddles when the ves-
sel is in rough water, or loaded deeply with cargo, or when
pressed over with canvas, but the screw is little affected by
any of these changes. This has already been shown with the
little vessel in question, and more than realizes the most san-
guine expectations of her projectors.
The screw employed was patented by Mr. Wooderoft, of
Manchester, several years since, but has not been generally
known, although, from the results, it has evidently greatvalue.
The pitch of the screw is not uniform, as usually made, but
expands or increases in the length of the pitch, the object
being, that as the water receives motion by the first impact of
the screw, the blade of the screw should follow it up with
greater rapidity. _

Mr. Grantham has shewn us drawings by which this plan
can be applied to ships of war, so that all the machinery shall
be below the water line. The government have lately
launched a large vessel to which the screw is to be applied ;
and, although the propeller is to be below water, the engine
is as vulnerable as ever, and it is much to be regretted that
the present principle was not known when this vessel was
commenced. Trials have been made in towing, and here the
superiority is equally obvious. As applied also to the ferries,
this principle is evidently of the greatest importance, and is
likely to prove an additional facility in crossing to Cheshire.
Messrs. Mather, Dixon, and Grantham have obtained a
patent for these improvements, and we wish them all the suc-
cess that the importance of the question demands.
It had always appeared to us that so long as it was neces-
sary to apply spur wheels, the screw propeller would never
be brought into general use, from the well known disadvan-
tages attending such machinery in vessels ; but now that we
see these objections removed, we can have little doubt that
th© paddle-wheels will be soon superseded.

FLIGHT OF THE DUBLIN CORPORATION TREASURER.—
Mr. Finn, the city treasurer, has absconded, bearing with
him a trifle of the, corporate
i funds to the tune of some thou-
sands—" say" 43000 ! It s even so ; and the excellent and
conscientious and trustworthy gentleman is at this present
i
writing enjoying himself on board the, Great Western, with a
hold forth to the
good offing and a " fin ; avo,n,ring gale,' 1,,
for
~
This uriating in s
all fun a cigar
e rate-payers, and the still more unfortunate holders of
city bends and debentures—the survivors of tontine and other
aiindagibausts what prospect mprrnosupt—ect dcooelds without.it
civic securities ? Sir J. K. James was a gentleman of station and
honour ; and he was, moreover—no
.bad ingredient in a trea-
surer of any description—a man of considerable wealth and
independent fortune. But he would cnot do for the pure and
immaculate town council. . They must, forsooth, have an
officer possessing their confidence—and they got him. It is
for this and such like appointments that they called upon the
citizens to pay a borough rate—for replacing
honest men by
schemers that the householders of Dublin are to be taxed.
,
This fellow, in whom the council had confidence," has
carried off with him all the money appropriated to pay the
lawful debts contracted by the corporation, for which pleas
of confession had been given—the stay of execution in each
of which will eipire this day, so that most probably by the
end of the week, we may have John Littledale, the auctioneer,
instead of George Roe, the lord mayor, hammering away at
the Mansion-house.—Dublin Matl.—The report to-day is
that the deficiency ranges between seven and ten thousand
pounds. A warrant has been issued for the apprehension of
Mr. Finn, and it will be forwarded by the Boston steamer on
the 4th instant. It appears that Finn sailed under the name
of Reynolds. He had two respectable sureties for £2,000
each.—Dublin paper of Wedgeiday.