The Sun.
London, England, 1864-03-18 00:00:00

The Double Screw at Sea.

The columns of The Sun have on various occasion 3
of late recorded trials of steam vessels fitted with
double or twin screws, trials which have excited
considerable interest from the great importance th©
principle under trial bore both towards the Royal
and mercantile marine, offering as it does a power of
naanceuvering a vessel when un:ler steam such as
never could have been attained by the single screw
or the paddle.. The public importance of the prin-
cipal has been fully acknowledged, indeed, by its
pirtial adoption by the Admiralty, and the t„,sti.
tnonv given to its merits in the House of Commons
by Lord Clarence Paget, Sir he. Elphinatone, and
others. These trials have hitherto taken place on

the comparatively smooth waters of the Thames,
but on Wcdnesday and Thursday, the 16th
and 17th inst., the twin screws reached their as yct
culminating point of success in the trial trip of the
Atalanta from London to Calais, and thence in a
race between that port and Dover with one of the
fastest boats of the London, Chatham, and Dovcr
Railway Company. The Atalanta is an iron vessel,
built by Messrs. J. and AV. Dudgeon, of Cubitt-

town-yard, Mil'wall; is 500 tons burden, 200 feet
long, 24 feet in breadth, 14 feet in depth, and is
driven by two screws, with independent engines,
the collective power being 200 horse. She is a
smart, clipper-looking craft, possessing at the same
time large carrying powers. On Wednesday she
left Gravesend at 15 minutes past twelve, in charge
of Mr; Leigh, Trinity Pilot, the wind being fresh
from E.S.E., and the young flood tide coming
up against her. The steam was up for the
first time, and it was, therefore, not intended
to make any official trial of her speed be-
tween the Thames and Calais, the port to which she
was first bound, but in passing the measured mile
in Long Reach she was found to be going 14 138

knots, which certainly appeared to confirm the
assertion of her builders that she would prove to be,
for her tonnege and horse power, the fastest screw
vessel afloat. The Nore lightship was passed at
21 minutes past 1, the greater part of the time the
port engine only having been at work, owing to
some adjustment being required to the starboard
crank bearings, but even under these disadvan-
tageous circumstances the distance, 224 miles, was
made in 75 minutes. The wind was now freshen-
ing, but the water was smooth and the weather
clear as tho vessel kept on her course
through the Oaze Deeps and the Alexandra
Channel, the engines making 120 revolutions
without a rattle, and doing their work magnifi-
cently. At 4.30 p.m. the held outline of the South
Foreland was merged in the general dark outline
of the English coact under the Atalanta's lee, while
the white cliffs of France west of Calais were rising
rapidly above the line of waters ahead. At 6 p.m.
the Atalanta was in her berth alongside the pier at
Calais, just ahead of the paddle mail packet Vivid,
with which she was to try her strength across the
Channel on the following day. The distance be-
tween the Downs and Calais could have been ace
complished in considerably less time, quick as it
really was, bat for the vessel having been kept on,
a mid-channel course between Dover and Calais for
some 10 miles, thus deviating from her direct course
for the latter place. On Thursday the Atalanta
crossed over from Calais to Dever, so as to steam back
from the latter to the former place in company with
the Vivid, which was appointed to leave with the
mail from Dover at 9 30. At 45 minutes past 9 the
Vivid came out, and the Atalanta having been,
placed in position as nearly as possible abreast
of her, the race across commenced. From the time
of starting the result was never for a moment in
doubt. The Vivid, pitching her bows into the sea as
she got clear of the land, was evidently making haul
work of it, and fast dropping astern of the Atalanta,
which, without throwing a drop of spray over her
deck, was making her way in splendid style, end
improving her position with every fresh puff of
wind and roll of the sea. As the French land was
neared the wind freshened, and as it so freshened
and the sea rose the better the Atalanta behaved.
Calais was reached in 77 minutes by the Atalanta,
bat the Vivid was 107 minutes—half an hour
behind the double screw. The success was of so
decided a character that it was considered un-
necessary to test the speed of the boat any fur-
ther, and a return course was therefore shaped
for the Thames, where she arrived at 5 p.m.,
and where she will complete her outfit for the
service for which she has been built. In crossing
the Channel the action of the screw on each quarter
was beautifully distinct through the deep, blue
clearness of the water, and it was surprising to
notice with what smooth solidity and entire absence
of water disturbance of any kind they worked.