Crawford avalanche. (Grayling, Mich.) 1879-19??, 1891-08-06

bubuAlueu sea speed. ................ II huOJs
indicssod horse power tsustainedj. 10000
Indicated horaa iraxuAs INA ~iss>s. s..A
The battery of the Pirate will consist
of eighteen machine guns, six torpedo
tubes, four six-inch b. l.. r. of high
power and eight four-inch b. l.. X.
rapid-fring guns. The six.inch guns
will be mounted in the open and pro-
tected by heavy shields attached to the
gun-carriages.
The arrangement of the motive pow
er will be novel in character, the force
being transmitted through three
screws, one placed amidships, as in
ordinary single-screw vessels. and two
others nlacad fA-ther forward. one on
eacn side, as is usual in twin-screw
vessels. This arrangement represents
the latest advance in steam engineer
ing where such great power is to be
transmitted, but 1t is not entirely new,
as it has been used by the French for
some of their later vessels.
If twin screws were used over 10, 600
1. II. P. would pass through single
shaft, but in this case each shaft trans
mits only $3.50. and the ship has in
edditiQn- ono mora ahanee ~, -e~ss----f---
breakdown.
The machinery consists of three sets
of triple expansion, vertical. inverted
cylinder engines, driving the triple
screws before mentioned, the center
screw being about four feet six inches
below the two others.
Each engine is placed in q water
tight compartment and is complete IN
every respect, so that the vessel may DO
propelled at slow speed by the center
scrow alone, by the two outer screws at
q medium speed, and by the three
screws when the highest of speed is re-
quired. Each shaft is fitted with q
disengaging coupling, so that, when
not in use, the propellers are free 10
Sevolve. A great advantage of this
arrangement is that it allows the ma
chinery to be worked at its maximum
and most economical number of revo-
buttons at all rates of the vessels
6ssad nbreRGR.hRsgilafs sal,yassnhs
vantage of great importance and one
that the arrangement of the two sets Of
engines working on the same screw
does not possess.
The total indicated horsepower at
129 revolutions per minute and forced
draught will be 2l,000. There will be
eight double-ended boilers placed in
four water-tight compartments, and
two single-ended auxiliary boilers on
the berth deck. The air tight fire.
room system of forced draught will be
used. All the boilers will be made Of
steel for working pressure of 160
pounds.
The vital portion of the vessel being
protected by an armored deck, the
space between this deck and the gun
deck will be infinitely subdivided by
coal bunkeEs and storerooms. In adj
dition to these, cofferdam five feet in
width will be worked next to the ships
side for the whole length of the YES
sci in bunkers. This will be filled
with patent fuel, forming q wall Ave
feet thick against machine-gun fire.
The contents can also be utilized A.
abaft the coal bunkers the coffardam
will be filed with some water-exolud-
ing snbstanoesimilart to ~woodise.'
In the wake of the 4-inch and ma
chine guns the ships sides will be
armed with four and two inch plates.
The 6-inch guns will be mounted in
the open, protected by heavy shields
attached to the un-carrisges. The
accommodations for officers and crew
are spacious, we'll ventilated and heat
ed. All the most approved modern
appliances for exhausting the vitiated
air and for incandescent lighting by
electricity have been incorporated in
the design The coal capacity is very
great. At ten-knot speed the Pirate
will have an endurance of 100 days or
q radius Of action of 26, $40 knots.