The Sun.
London, England, 1840-06-23 00:00:00

It might be supposed that-
the propelling gear, being
so near to the stern-post, the vessel would be difficult to
steer. The contrary is, however, the fact. She takes
her helm most readily, and will turn within an unusually
small space. The propulsion being right on end, and
under water, (rives her a decided advantage over vessels
worked by paddle-wheels, one of which may pull more
or less at her side according to its immersion or abstrac-
tion from the water, particularly in a sea-way. So little
tendency has the screw to give an unsteady direction to
the vessel, that when she was put head to wind she
steamed on in a straight course without a hand at the
helm for some minutes together. On a lee shore a
small screw engine would doubtless be effectual when
other means had failed in preserving life and property in
merchani-ships. The Archimedes is provided with4a
steam-whistle, like those of ra•lway locomotives, a useful
contrivance, to warn vessels of her being near during
fogs, &c.
In noticing thus favourably Mr. Smith's screw pro-
peller, we have no object to serve but to bring it fairly
before the public, who must be the final arbiters as re-
gards its merits. We may possibly over-rate its present
practicable efficiency, and its probable improvements ;
but we incline to think that its introduction will at no
distant period be general, and that it may give rise to a
new era in steam navigation. For ourselves, if the feel-
ing of en% y belonged to our nature we should envy Mr.
Smith. NVe had rather be the author of this simple but
wonderful " Essay on Ocean," than of Pope's " Essay on
Man," for this admirable application of the screw of the
great mechanical philosopher of Syracuse may do more
good for humanity than all the fine perceptions of the
poet, however adorned by the graces of language.
But we must proceed to a short notice of
TIIE TRIP ON WEDNESDAY.

At twelve o'clock about seventy or eighty gentlemen
of the first respectability embarked in the Archimedes,
on her second experimental trip. The day was, as
before, remarkably propitious, and the attention of
Captain Chappell and the worthy inventor in offering
every explanation with respect to the vessel and its
mechanism was unremitting. As we have already
given so minute a description of the steamer and de-
tailed fully the principle of its propelling power, we
consider it. only necessary to add one or two additional
particulars, more especially as the route taken was
precisely similar to that adopted• on the previous day.
We may premise, however, in passing, that her
second trip has only tended to confirm our
former favourably expressed opinion of this novel
application. Shortly before reaching the Crosby
Light-ship, the Duchess of Lancaster steamship
was perceived making directly for the port, and as she
was known to be a remarkably fast sailer, and Mr.
Smith being desirous of proving the capabilities of the
Archimedes, immediately " put about,"and awaited the
arrival of the former vessel. On coming up. the screw
was immediately put in motion, and the two vessels
went admirably together for some distance, though we
are hound in fairness to state that the Duchess had a '
very slight advantage in respect of speed, owing, as will
be seen from the subjoined comparison, to her propor-
tions as to power, draught, &c., being better adapted
for quick sailing. The Archimedes had also the full
strength of the tide to contend with, whilst her com-
petitor ran the whole distance in the eddy. This is the
first time the Archimedes has been beaten, with the
slight exceptions above noticed.
ARCHIMEDES. I DUCHESS OF LANCASTER.
Diameter of cylinder 37 in. Diameter of cylinder ... 40 in.
Stroke
Tonnage ..237 Tonnage 03S
Draught
Estimated steam-power, !Estimated steam-power
80.horsei 90-horse
Length between perpen- Length between perpen-
diculars 107 ft.! diculars l2O ft.
Ilea m
Area et airiciahip.kiK*l*.g.,4r /Ana of _u4siship section-- - -
at 10 feet draught. ft. at 6 feet draught 100 ft.
-- - .

We may also add that the Archinzedes had that
morning taken in a four day's supply of coals, whilst
the Duchess may fairly be presumed, on the termina-
tion of her voyage, to have had a very small quantity
on board. It was the decided conviction of the whole
company, that had the vessels been on equal terms the
result would have been the reverse.

The company were landed about half past four, all
equally delighted with their gratifying excursion.
As there was a feeling on board relative to the slip
or loss of power from th screw, the lollorving explana-
tion will doubtless be satisfactory :—The screw, being
8 feet pitch, would, if working in a solid, advance
8 feet for each revolution ; but, working in a fluid, the
relati‘e difft-rence between the speed of the screw and
the vessel appears, at first sight, to be considerable,
from the supposed oblique action of the propeller. The
following mode of calculating the speed of both will
show that the dlfference is barely one-sixth, which is
considerably less than that of ordinary paddle-wheels.
The number of revolutions of the engine per minute
is 26, which, multiplied by the spur wheels 51 times,
gives that number of turns to the screw for one of the

26 revolutions of the engine per minute.
5! multiple.

138 revolutions of the screw per minute.
8 feet pitch of the screw.

1,104
.feet travelled per minute.
20 being lof 60, to bring it into

22,080 yards per hour.
which, divided by 1,760 (the number of yards in a sta-
tute mile), gives us 12 miles 160 yards per hour as the
speed of the screw. Speed of the vessel for 26 strokes
per minute, 10.10-25 miles per hour by the log.
As we remarked at the commencement, we must
leave our readers to judge from the facts we have stated
as to the general adoption of this mode of propulsion ;
but there seems to be only one opinion as to its supe-
riority to that now in use amongst all the scientific and
practical gentlemen with whom we have conversed.
We feel assured that all who have witnessed tbe qua-
lifications of the Archimedes will testify that none of our
statements are exaggerated. We can only add, in
closing our remarks, an earnest hope that Mr. Smith's
success may be commensurate with his talents, perse-
verance, and outlay of capital, and in the words of a
gallant old Admiral, " May his screw be long, and
long may he screw."