Delaware state journal. [volume] (Wilmington, Del.) 1870-1883, 1880-07-01
A PROMISING INTENTION.
Am Important improvement i'm Conn
pound Marine Engines.

Am Important improvement i'm Conn
pound Marine Engines.
New York Times.
The improvements made in marine
steam engines few years ago by the
introduction of what is known as the
compound engine is likely to be supple
mented by another invention which is
practically a development of the same
principle. Mr.. LOTUS Perkins, the
deviser of the compound marine eugine,
has constructed a new machine, 10y the aid
of which he proposes to cross the Atlantic
in small steamer of 20 tons, called the
Anthracite. The governing idea in the
compound engine is that when steam has
been heated equivalent to pressure, of,
say, 40 pounds to the square inch, it
needs but very slight addition OF fuel to
increase the pressure to 120 or 100 pounds.
These engines, therefore, have two
cylinders, small one, in which the steam
is confined at a high pressure, and o
larger one, in which, MS il is needed, it is
allowed to expand itself. In consequence
of this contrivance, the consumption of
coal on our ocean steamers has
been very greatly reduced, and
about the same propelling power can
be obtained by daily consumption of 40
tons of fuel rs was formerly secured by
burning 100 tons per diem. What MIR.
Perkins has now done has been to carry
this principle yet further. Why stop, he
seems TO have reasoned, at 100 pounds
pressure! When this degree of heat has
been obtained, it is an easy matter to in.
crease it to pressure of 800 pounds, aud
then you have at command vastly greater
power. The obstacle in tine way of
applying this system to the ordinary com
pound engine was that the difference
between the pressure of steam in the
storage and working cylinders was loo
great for its easy tranmissioD from oneitO
| the other, and to overcome this he has
| had recourse 10 an intermediate cylinder,
that il, the steam on the Anth,uCite il
heated in the boilers up 10 o temperature
| equivalent to pressure of 800 pounds to
| the square inch, and then passes into 4
| cylinder s inches in diameter, thence
| into a cylinder Ii inches in diameter anc
lastly into one having diameter of .;
inches, where it acts directly in propellint
| the vessel.
| 1t will ut once be seen that this consti
tutes an immense economy of force, con
cedipg, MS all who have looked into the
matter must, that the great outlay in fuc
| is in raising the heat of the vapor to it
ordinary working degree. by MIR. Perk
| ms new method this force is iEcreaset
tenfold, with buta relatively slight addition
TO the heating medium. One possible de
| feet in this arrangement that will readily
| suggest itgelf to The reader is the intens
strain which pressure Of this kind mus
put upon tue boiier5 of an ocean steamer
aud their consequent liability TO explosion
Steam, at n tension Of 500 pounds To tn
| SQUARE, is an enormous force to be con
fined, and the explosion OF large boile
under these conditions would make shor
work OF the stoutpst ship that ever tionted
But this is contingency that Mr.. Perk
ms has not overlooked, and to meet it h
has constructed u boiler for his littl
steamer on an entirely new model. 1t
composed Of horizontal tubes welded u
at each end and connected together b
small vertical pipes, the whole hsvin
been tested to stand strain OF ., ~
pounds to the square inch, thong
whether the trial was by steam or col
water pressure is not stated. However
| the claim that he makes is that the sui
division is such that if an explosion shoul
occur it could not do material damag,
! for it would Of necessity be confined t
I | one of the numerous horizontal tubes an
, from this seLt the steam would readil
/ escape. .... .."...
! This is a nlAtter that can he testt
. better by experience than by theoret
4 reasoning; while at the same time ii mu
: be admitted that the theory seems q sour
I all a.
/ might be q considerable waste of hea
G But when the Anttraeite has made b
o trip ACROSS the Atlantic to this port, Il
s data for judgment will be supplied that
d now wanting. Tie immediate advantal
n TO us OF this improvement is in the pre-
/ pect it holds out of greatly reducing Il
l. cost of ocean transportation. Eve
,e invention that tends to lessen the eE pen
ID of carrying cargo across the Atlantic il
lie direct gain to the people of this countr
or The saving made does not go to al
" perceptible extent to the owners of t
ID steamships, for they are compelled
Or keen competition to content themsely
I'd with certain moderate return on the
to investments. Those who are benefit
m are the consumers of the msrchend
carried and the producers who, in con
~ | quenee Of low freight rates, can send tn
is wares to markets that, under other con
10 tions, would not be opened to them. II
a not easy to make close estimate of I
In gain, but it is safe to say that if the co
Iv pound engine had never been invented
es should not now have anything Rpproat
nj ing cur present hold on the Eugl
he market, aid if the 800 tons of coal Il
-er the faster steamers now burn on
or Atlantic voyage, and the 300 tons that
freight boats consume, can be reduced
spectiyely to 200 and l06 with corr
ponding reduction in the number of CT
beavers employed, the consequent deere
cit in rates of freight will be sufficient to I
a mit US to sell our grain in Liverpool "
rk' profit at lower prices than ever before,
me to ship it and other articles to mari
"a that are not now open to us. America
Ike no less than the English, have good rea
as for hoping that Mr.. Perkins latest inv
ton will prove success.