National Republican., 1885-03-03

In accordance with tho provisions Of
The bill passed during the lrst session Of
the present congress- providing for the con-
struction OF the steel cruisers, tho manufac-
ture of portion Of the steel guns provided
for therein was begun at the Washington
navy yard about Jan. 1, 1884. These guns
are as follows Four s-inch, ten 6-inch,
and two 5.inch. In addition to these
there are two 10.inch guns in course Of
manufacture for the Miantonomoh.
A greater portion Of tho steel for the
Jtuns was received from the Midvale Steel
Il Works, Nicetown, Philadelphia, Pa,
where IL was manufactured. Tho tubes
and jackets are rough turned and rough
bored ut the navy yard and then returned
to the Midvale Steel Company for oil tenn
pering, which is done at tho expense Of
tho company, for the purpose Of raising
The motal up TO the requirements. Tho
oil tempering Is more effective after the
forgings are bored than it would be IL
done before boring.
Many parts of tho guns arc oll-tom-
percd ut the navy yard.
THE PROCESS CONSISTS
of.immersing the steel at q cherry heat
in bath OF oil, and there allowing II to
cool. For this purpose there Is largo
tank sunk in tho ground about IL feet
deep, with q diameter Of 8 feet, and hold
ing 1000 gallons of oil. It Is necessary
to have the liquid In which tho steel is
immersed at low temperature, and to
this end the tank is constructed with
double sides, making 5-iuch space
around the inner tank, through which
water cirCulates. BY this means the tenn
perature of the oil Is reduced to about 81
| degrees, in which the steel, heated to a
temperature of over $50 degrees, is i'm
morsed. Sperm oil was at first used, but
cotton-seed oil is now substituted, rs II is
much cheaper and answers the purpose
equally as we'll US sperm oil.
ON COOLING
j the steel Is tested to ascertain tho tensile
strength, elasticity, and extension, and it
js often necessary to repeat the process or
to anneal IL.
THE ANNEALING PROCESS
Is conducted by burying the metal in a
tank filled with sand under which fire
is built and banked and the whole al
lowed TO cool. When the steel is taken
out 1t possesses increased ductiity.
After the tubes and jackets have been
tempered at tho Midvale Works and
specimens from them tested and approved
n they are again sent to tho navy yard
where they are fine bored aud fine turned
preparatory TO assembling with the other
parts of the gun.
THE TINE REQUIRED
to complete one of these guns Is about
tix months. During the early stage OF
she work the progress is more rapid than
later on, as each of the parts, oil which
there are from fourteen to twenty, accord
/ ing to the size of the gun, can be worked
on separately, but as the work progresses
and the parts are assembled fewer work.
men can be employed on the gun.
The most interesting item of the work
of assembling the parts is in shrinking
the jacket and hoops on tho tube. The
Jacket is the enlarged part of the breech
of the gun, the inner measurement OF
which is made about 2-100 of an inch
smaller than the outer measurement oil
the tube over which II is placed. This
is done by heating the jacket to TEN.
perature sufficient to expand it to q size
slightly larger than the tube. Consider
able skill is necessary In calculating and
obtaining this shrnkage, as tho differ
ence in the sizes of the two measure.
ments is called, SO as to make tho jacket
only Of sufficient size to pass over the
tube when heated and to fit firmly wher
it cools. Too great n shrinkage would
cause strain on the metal, while tot
little would prevent the jacket having Q
strong hold.
THE PROCESS OF REMOVING
jacket from its tube, ns ia sometimes
necessary, is by arranging the gun so tina
molten metal may be poured around thI
Jacket the heat giving it an expansion
sufficient to draw tho tube out. Tn,
main point In this process is to raise the
tube from the jacket Immediately it Il
loosened, as during short delay tn
tube would expand proportionately ant
prevent its being drawn from its Jacket
After the Jacket is fitted on the tube
the hoops, which are additional strength
ening bands, are then shrunk on in lik
manner. These hoops number six il
the 5-inch and 6-inch guns and nine II
the S-inch and 10-inch guns, and ar
placed on the tube side by side, addin
greatly to the strength of the gun, 81
that even In tho event Of the tube crack
ing these hoops would
PREVENT A RUPTURE.
OF these guns four have been com
pleted, and one, o 6-inch, has been testeC
at the Annapolis proving grounds. 1t il
claimed that 1t stood higher test thai
any similar gun ever manufactured
This good report coming from the frs
American steel gun ever turned out fore
tells n high standard Of armament 70
the new steel cruisers.
The length aud weight of guns, weigh
ofprojectilcs, and amount of powder re
quired for each fire Of these guns are q
follows: Ten-inch, length 27l feet
weight $1,000 pounds. weight of proectil
500 pounds, powder 250 pounds; s-inct
length 81 feet, weight 27,500 pound.
weight of proIectile 250 pounds, powde
1875 pounds; G-inch. length IL feet, weigh
1000 pounds, weight of projectile 10
pounds, powder 80 pounds; 5-inch, lengt
13 feet, weight 6,200 pounds, weight Q
proectile 60 pounds, powder 80 pounds.
TWO OF THE s-INcH GUNS
W will 60 to tho Atlanta and two to the Bot
ton; the 6-inch guns will be divided bC
tween the Atlanta and Boston, and tn
5-inch will go to the Chicago.
The ordnance department employs %
men, which is nearly one-half the whol
number of employees in the navy yart
The ordnance machine shop, being to
IH chine shops of all the other department
r. have been brought into use for Ordnanc
n work.
These guns are not only made of Amer
lean steel, by American workmen, bu
<M are also entirely of American design, b,
ing designed mostly at the bureau of orc
M nance, navy department The breec
closure, which is known as the slotto
q screw systom, was an original idea wit
Il Mr.. Benjamin Chambers, formerly of tn
city. 1t was tested by the late Admir-
T. Farragut in 1851, and with modification
has been adopted by both the army an
z. navy, and has since become popular wit
and is rapidly being adopted by Europea
U gun manufacturers. 100
"a A slotted screw is an arrangement fc
X gripping the plug securely in the breec
M of gun after loading. The sections
f. screw threads on the inside of the breec
are arranged alternately with slots {
54 blank sections Of equal width 80 that I'll
corresponding screw and slot sections o