New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1905-12-01
THE CARnAgIA,s ENGINES.

The first transatlantic steamship propelled by
steam turbines which will run between British
ports and New-York is to start on her maiden
voyage from Liverpool tomorrow, The incident
is of more than local Importance. Peculiar In
terest attaches to the exhibition of her qualities
which the Carmania will give, because, except
Ger her motive machinery she is an exact dupli-
cate of the Caronia. The comparison which Is
thus made possible should prove especially IN
stru1tive owing to the size Of these vessels. The
Carmauia is the largest turbine steamship ahoat.
When fully loaded she will have displacement
more than twice as great as that OF the Nlr-
ginian and the Victorian, which have engines of
the same type. Moreover. the Carmania and the
Caronia are half as large again as the Lucan!a
and the Campania, their immediate predecessors
in the Cunard. companys service. Hitherto most
of the tests of the fitness Of Mr.. Parsonss inven-
ton for marine work have been made with small
yessels-torpedo boat destroyers steam yachts
and Channel steamers What is chiefly needed
now is a demonstration of its adaptation to ships
of large tonnage *>s. #~@~~ ~
During her trials nearly year ago, the Caro-
MIA trGversed measured mile four times at
mean speed of 1852 knots. She thus showed her
ability to maintain average of about nineteen
knots for several days The mean capacity of
her engines was trife less than $4,000 horse
power although a maximum Of 23,500 was at
tanned during a momentary squirt The engines
of the Carmania were designed merely to equal
those of the Caronia in power, but a good many
persons will be surprised If she does not develop
mean speed of twenty or even twenty-one knots
for the whole of voyage. She may not do her
prettiest the first time she crosses the ocean.
Few steamers do. No matter how nicely the
shRft bearings are adjusted, they usually need
some wear to reduce the friction to minimum.
Besides unforeseen trouble with boilers occa-
sionalIy prevents the best performance of which
a ship is capable. Hence it will not do to expect
great things Of the Carmania until she has made
several trips across the Atlantic.
The turbine is credited with superiority over
the reciprocating engine in eight or ten particu-
lars. OF these perhaps the most important is its
economy in the consumption Of steam. This
quality, however, is displayed only when the
engine is run at more than 60 per cent of its
capacity. At low speeds the advantage disap-
pears. In the merchant marine however q close
approach to the maximum speed is essential be-
cause in transportation time is money. What
ever doubt there may be, then, concerning the
suitability of the turbine to naval service this
one merit Is strong recommendation for use
in ships like the Carmania.
Besides its comparative ineficiency ut low
speeds. the turbine developed two other faults,
but both have now been remedied. The exceed
ingly rapid rotation of the shafts In the first en-
gines demanded remarkable multiplication OF
screws. The turbine had nine propellers, three
on each shaft. A reduction in rotary speed has
made It possible also to reduce the number OF
propellers The Carmania has only one on each
of her three shafts. Again, d turbine reyolyes
only in one direction and cannot be reversed
By supplementing the main engine with smaller
one, designed to turn the other way, the same
object is secured. Recent tests show that tur-
bine steamer can be stopped backed and ma
n9uvred quickly as any other Of equal size
and power equipment. 1t IS possible, of course.
that other defects will he discovered. No large
turbine has vet been subjected TO the test Of con-
tinued use for ten years The very form of the
mechanism has eliminated the need of one class
of repairs. What others may be required only
time can tell Still few engineers whose judg-
ment is uninfuenced betray anxiety on that
score. Unless the Carnania should offer other
testimony than is expected. therefore. the advan-
tages already manifested viii for 2 while sustain
the popularity Of the turbine.