The San Francisco call., 1897-07-18
A MONSI Err GUN.


tifcations. submitted in 1885, it was esti-
mated that fortv-four 16-nch breech-loading
steel rifles would be required, of which num-
Der ten were assigned to San Francisco. Al
though this report was the starting point ana
foundation OF subsequent coast-defense legis-
lation I6-inch guns have never been appro-
priated for, the heaviest gun mounted thus
far being the 12-inch.
The ordnance experts of the army were nat
urally desirous of undertaking the construc-
tion of 125- ton gun. and plans were accord
ingly prepared and the matter urged upon
Congress. At last the construction OF type
16-nch gun was authorized. and is now being
built This will be by far the most powerful
gun ever undertaken in the United States, and
is surpassed by only g few abroad. 1t will be
of the same general design Ton the built-up,
forged steel principle) as the other heavy Cali
bers of our system.
Few people, aside from those directly con-
cerned in the design and building OF such q
gun, can appreciate the difficulties which
must be met and overcome when any increase
OF caliber over the present is undertaken. If
a 20 or even 40-inch gun were prepared
most people would take it as a matter of
course, but it is altogether pro bable that the
limit of caliber has already been reached. The
difficulties win be appreciated from the state
ment that in our g. 10 and II inch guns, each
weighs approximately twice as much as the
next smaller caliber, burns twice the amount
OF powder and hurls projectile of twice the
weight. In passing from the 12-inch to the
16-inch the difference is even greater.
Caliber alone is but one element of guns
power. There are no modern guns of q cali
ber approaching some of those built centuries
ago by the Turks and Russians while in the
sixties we had our own 20-iuch Rodman cast
iron gun. The power of a gun is measured by
the energy of its pro jectile, and this in turn
depe, ds upon the latters weight and
velocity.
Those who saw the big Krupp gun at the
Worlds Fair can form good idea of the ap-
pearance of what will be the biggest of Uncle
Sans pets. 1t will be nearly so feet long, its
largest diameter will be 81 inches and its
weight will be 100000 pounds The charge
OF powder fred in the new gun will be 1860
pounds This will give to the 1850 pound
projectile a velocity a the muzzle of 1875 feet
per second or over twenty times the velocity
of a train moving mile minute. Expressed
in other terms, the steel pro ile as 1t leaves
the gun has an energy OF GA. .0S4 foot tons.
Some idea of this enormous energy may be
formed when it is realized that the shot Is
capable of penetrating 81 inches of solid steel
AT the muzzle of the gun, while at distance
OF $500 yards, or two miles, II still has suffi-
Cicut FelOClty 10 pleICt 20 iHCncS. IAese ut-
tails are the subject of long and very la borious
calculations and are all determined before the
first forging is made. To provide suita BILE
carriage capable OF standing the recoil is
almost or quite as difficult matter as build
ing the gun itself.
The foreign gun most nearly resembling the
new 16-inch gun is the KrupP 40-centimeter
Us rs inch). Of 119 tons, but ours is of con-
slider iably higher power. The long struggle
sldered as definitely settled in favor of the
gun. For time the Harvey arnlor had the
better Of it, but cuIiously enough, by the sim
pie expedient of placing cap OF soft metal
over the end of the projectile, armor is easily
penetrated which would break up an un-
capped prcisctile. AS the 12-inch gun is suffi-
cient for all ordinary requirements and ships
already have reached or passed the limit OF
armor-bearing, it is questionable whether the
16-inch gun will ever be manufactured in any
considerable numbers.
Considering the greatly increased cost OF
the larger caliber it seems most likely that
the decision will be in favor OF number of
smaller calib. .rs, such as 10 aad II inch, in
stead OF n limited mum ber of the largest size.
There are certain situations, however, where
space is a consideration, in which the true
policy will be to mount a few of the very
heaviest calibers This will be especially the
case in turrets mounted In exposed situations,
such as reefs Here the gun must certainly
be more than a match Tor anything which
can be brought against ii, otherwise it will
be OF little use.