The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1857-10-18
Screw Steamer and Paddle Stsamsrs-Ix,,
vsxs1S Wood.

| owners We see from unnistAkeable data that
nine. tsuths Of al the steam vessels now building
ard lately built In Great Britain are iron screw
pfepeilers. Wehsve lately seen Q 'statement of
the Chief Engineer of the Royal Dookyard at
Wcoiwich, England, in relation to the increased
consumption Of fuel In marine engines to obtain
increased speed" From this we learn that as the
speed Of steamer increases the expense increases
in almost gecmetrical proportion. For instance,
steamship with capacity or displacement
of 5000 tons, and engines Of SO horse power, can
stesm six miles an hour. Such . vessel with 200
tons OF coal will steam 4,l54 miles in twenty
eight days twenty hours, and carry 1898 tons of
freight. Another steamer Of the same size, with
eogines of 4l6 horse power, will run twelve miles
IN hour, carry 7s4 tons Of freight, and in four
| teen days ten hours 60 distance of
asa miles, and consume 1900 tons of coal.
Another vessel OF the same capacity, with engines
Of l75 horse power, will run nine miles an hour
and with 200 tonsof coal will steam ,i07 miles;
perfotmit in thirty four dsyssevenhou andcairy
| OPS tons Of freight When 1t comes to eighteen
miles an hour, the vessel Of 5000 tons has about
attained ite maximum. The hull and engines
alone will weigh 1905 tons. The engines Of
! LAOS horse power, with 600 tons of coal and 80
tons OF freight, viii steam in two days and three
hours Assistance of 922 miles. At nineteen miles IA
hour, with engines of l652 horse power, the YES
sci (of 5000 tons) can take $50 tons Of COAL have
room for only 70 tons of freight, and steam In
eleven hours distance Of 207 miles. With much
larger vessels perhaps higher rate of speed
could be attained.
Now the question that we ask is, are these cal
culations true Of the latest inventions and most
approved engines, and when applied to the screw
prcpellers? The data here given probably refer
to the paddle wheel more directly than to The
screw. It was thought for long time that screw
steamers could not be made to run as fast as
those propelled with the paddle The reason
Why they have not usually made as good time
has been because Of their small engines-many
of them depending largely on their sails. Screw
steamers can make IS good time ss those With
| paddle wheels: witness the late run of the Ma
CARA, leaving some Of the crack steamers Of the
British rayy hull down in the distance in few
hours. The monster screw vessel Himalaya
steamed from Halifax, N. s., to Portsmouth, Eng
land, In nine days and few hours An extract
from late Edinburg payor--the Couant now
before us, says:-"W notice the arrival at Leith
Of handsome new Clyde built screw steamer
named the Hollywood, intended for the Rotterdam
trade. She appears to possess considerable cspa-
city for the stowage of cargo; has elegant accom-
modations in a cabin on deck for limited num-
Der of passengers; and, according to q tele-
graphic communication received by the owners,
has made her first trip to Rotterdam in a much
shorter time than has ever been docc by any
steamer
The difference between screw and paddle
steamer is this The paddle wheels require
more costly engine, and the machinery takes up
much more room. A paddle wheel steamer can
make but little use Of her sails in fact, the rig
gipg and spars, when the sails are farled, take
so much wind that il II doubtful If sails are, in
the long run, Of any advantage Then, in q
fresh breeze, the steamer careens so much that
often one paddle IL almost or quite out of the
water, while the other is submerged to an extent
that renders it nearly useless. Let screw
steamer careen ever so much the screw is CON
stantly at work. That is not all. The screw.
from its position, presses constantly on the
water, AID loses no power, while two thirds Of
paddle wheel is in the air, doing no service.
while power is constantly Lost or thrown away in
lifting its long arms and the back water Al
experience, as well as theory aud mechanical
science, prove that the scrca is fast driving the
paddle wheel from the ocean. Had the great
superiority OF the screw been known at an
earlier day, much money would have been
saved.
ADd re- TO material, we must go TO building
iron steamers The Dundee id,ertyr has some
remarks Illustrating their superiority. The fact
II, the proprietors Of crazy old ships-square-
headed, Dutch bottomed antiquities annot or
viii not. sec that their cumbrous old concerns
have thick planking and massive ribs and that
tie Displacement Of freight by these is a consde-
lahle 1T of against the displacement caused by
,nglnts ard boilers. The heavily-timbcrcd old
shipmastcr eyes The ponderous beams Of bis lub.
bCTly old craft, and snccrs salt water sheer at
the wire work frames Of iron vessels,
forcctfcl all the time that but FOR such
wire work, introduced az fastenings into
his slip, the clun.y craft would fall in pieces
Jy her own weight. The preiudiced old mariner
cries, Give me wood for my money oblivious of
The fact that it almost exceeds the carpenters
art 20 construct of wood such vessels ar
the Persia, Scotia and Great Eastern, vessels
which are respectively so, 100 aud 500 feet
long The Pict's boat Of patchwork
and sewn hide was not lighter in proportion than
il the willow like frame work and .heetlike skin
Of the world-famed Persia. Another advantage
Of iron a. building material, is that II neither
cracks in the SUM- nor rots in the wet; keep il
well painted and il knows neither dry rot nor wet
rot, absorl,s no water grows no heavier; and we
believe that many iron ships some years of age,
are now . sound and as good az they were on