The republic. [volume] (Washington [D.C.]) 1849-1853, 1852-08-25

using the screw propeller. The English are now
using it, as auxiliary to sails, and applying il TO
their ships Of the line, am told that they are
now putting a screw-propcller in a ship which 10
twelve feet longer than the Pennsylvania. They
are building for war purposes now none but screw
propellers. believe that it ia the universal opin-
ion Of the navy certainly it ID the opinion of every
officer Of our navy with whom have conyersed--
that there 10 no other mode of using steam, which
ID adapted to war purposes, except by the screw-
propeller. Captain Halstead gives the reason for
this. lie says to reduce the matter to an axiom
attic form that she best with the aid of her
sails, and sails best with the aid of the screw,
while paddle wheel steamer paddles best with
out her sais. and sails best without her paddles.
In the one case the two auxiliary to, while
in the latter the the efficiency of. the
other. Another difference, Captain Halstead
says, lie, that with screw propeller you can go to
sea with small supply OF coal, and carry large
freight Of other things, whilst with the sidc-wheel
paddle you have to 60 to sea with large supply of
coal and small supply Of other things. lie says
it has been proved in the merchant service that the
auxiliary screw-steamers can carry freight at
twenty two per cent less than the Others He says,
further, that the expense of a ten thousand horse
power, with paddle. wheel machinery, would DO
E245, 900; just one half that amount would be ne
cessary If you use the screw propeller. He says,
also, that the very service for which the British
paying paddle wheel steamers l2s. Cd, or about
IS per mile. to perform, was offered to he per-
formed by screw ste aners ut %. 3d. mile; that
the difference between the cost OF employing
steamers and paddle-wbeel steamers was the diff
ference between paying Is. Sd. or &c. Id. mile,
and l2s. cd. mile. find, too, that in the exami-
nation in England, in lSiS, Lord Auckland Gays
the English are using the screw propeller* to
large extent as an auxiliary power in the mer
chant service; and Mr.. Ward said that they had
answered perfectly in the Holland trade when
they had been tried. He WINS asked in ls4s: care
you aware whether it has become common in the
merchant service to use the screw propeller" lie
answered.: ....
cit ID extending in the merchant service, and
has produced some very curious results. Tho ex
poriments had been particularly successful in the
case of those small schoOners which are built for
the trade with Holland, and they seem to have
occupy only one-s seventh of the vessel, while the
engines Of the Blenhern occupy nearly one third.
And they attain very considerable speed-eight
knots, eight and half knots, and nine knots.
The screw is never raised. The aperturcs are all
immersed, and the voyage of two hundred and
sixty miles, upon long series Of experiments,
averages about thirty six hours" a.'.e
Twas shown this morning letter just received
from Boston, from gentleman of high authority
and great experience in such matters, which says:
"My opinion is 30 strongly in favor of propeng
with strong auxiliary steam, that believeif two
steamers wero to be sent on survey, or n naval
cruise Of any kind, the paddle starting to day. and
the propeller being laid down month hence, at
the end Of eighteen months the latter would be
ahead in her work, at cost Of fifty per cent. less
In short, the paddle must be constantly near tho
coal yard and the machine shop, while the other
would DO independent Of both"
Indeed, he says much to justify the opinion that
the screw propeller, an auxiliary, is destined to
make revolution in the merchant service. 1t is
q fact Of which have sort of doubt. was told
on Monday, at the Navy Department, that they
had made a comparison of the log of the ''San ia.
einto," before her machinery broke down, with the
log of the "Saranac," tho "San Jaci,to' being
propeller, and the "Saranac" side-wheel
steamer. The Saranac" beat the "San Jacinto''
less than three per cent. in point of speed, while
the superiority, in every other respect, was with
the d" San Jacinto." Captain Halstead says, at
PIP. g. and So: $685..
"Of armed vessels tho Terrible has been &C.
lected for comparison because she is the pow
erfully equipped paddle-steamer in the navy
fully rejecting all distances performed when tow.
ing. when cruising, or when disabled in machine.
~, find, from the special reports Of tho Terri
ble, that she performed, in 1876, al, and '4S, a
mean rate, or duty of ship Of 6.S3 knots per
hour. This is vessel of SAT tons, and 800 horsc
power, or with proportion OF one-h horse power TO
every 23l tons. But it must be observed, with
regard to the armed steamer, that, unlike the
sister ship in mail employ, sho is required for the
sake Of economy, to use her canvas whenever pos
sibc; and, Of the whole distance completed by the
Terrible 6,277 miles. or forty per cent. OF it.
was performed under sail alone.
"Now, we have seen that the two auxiliary yes
sells which have been quoted as standards, perform
cd eighty. nine voyages in the year lS47. making
good distance Of As, 54S miles, and showine a
mean rate, or duty Of ship of 8 .25 knots per
hour"
Again he says it has been found, inasmuch "a
the screw and sails auxiliary to each other,
that, instead of having to build them OF clumsy
moulds, as heretofore, these steamers con be built
OF the very finest forms. II were to hazard a
conjecture, would say that l have no doubt the
day will come when tho screw propeller, an
auxiliary, will be used with our fast clippers, and
make the finest merchant ships in the world. .
Extracts from q work entitled "The Screw
fleet of the Navy" by Captain E. P. Hastead, of
the English Navy. He coInmends the adoption Of
screw ships in the Brazil mail service, for the fol-
lowing reasons: At page 81 --. .l...sr ... D..
"Bccause it 10 a principle which is capable OF
reducing public expenditure, at the same time
that IT improves general commercc. because II
takes less out of the public purse and puts more
Ah'o piFotS ouoeS W"iO pouute popuisloh diaW5
very largely upon both; for, instead of carrying
goods, the paddle is compelled to carry Goals
only, and then it calls upon all of to pay for
the expense OF burning them"
And again, he says, at page SO:
81 am not in error when state that the practi-
cal difference between paddle propulsion and
screw propulsion-that is to say, between large
ships carrying large cargoes OF coal and small
cargocs of goods, amounts to this, viz That the
auxlliaries arc able to make profitable return
upon ireights which are twenty-five per cent
lower than those demanded by the full powered
steamer" .l..... .
WHO CELEBRATIoN.-The Wings of Louisville,
Kentucky, making preparations to celebrate