The Calhoun chronicle. [volume] (Grantsville, W. Va.) 1883-1984, 1902-02-11
TESTING THE BIG GUNS
MINUTE OBSERVATIONS MADE AT
THE PROVING. cRoUNDS.

CIV OF two Magnets, "a steel Rod, and
Knife Bladc-A Methodical Operation
The Government ordnance proving
ground ut Sandy Hook is Il busy and
thunderingly noisy place just at this
season of the year, and every week
thousands of dollars worth of armor
plate. projCctiles and powder are util-
lZed I'm demonstrating that this coun.
Try possesses the best guns. the best
steel armOr. and the most efficient eX-
plosiNeS i'm the world. 1t seems al
most wanton waste of material to
heaVe pOndcrOuS steel shell or armor-
piercing projcctile. which is the prod
net of the finest machinery. against n
steel plate which has required the work
OF many men and years of experiment
ing to bring it to it's perfection. and
submit it TO demolition.
But Governments are proWerbially
prodigal when il comes to testing these
offensive ana defensive weapons. their
substitutes for wooden walls" II
would indeed he niggardly to count
the cost of even half n dozen armor
plates, several hundred pounds of pow
der, and Il dozen or more steel shot
and weigh ii against the millions rem
resented in battle-ship, TO say moth
ing of the lives of four hundred men
and the dignity of the nations flag
Time was when the testing of Il gun
was, viewedin present lights. Il slipshod.
unsatisfactory sort of process. Much
was taken for granted after the piece
had demonstrated its ability to hold
together during the strain of n dis
charge. There We're few of the nice
ties OF gun test But now the PROV
ING of gun is as careful and method
zeal an operation as the testing of Il
watch Not only must 1t hold to-
gether, but it must demonstrate its in
tention to hold together under rapid
and continuous use, it must show itself
capable of giving the projcctiles n high
velocity, comparatively fiat traiec-
tory and be as good gun afterward as
IL was when it left the lathe and the
pit.
Velocity is the thing. for that means
range and penetration. The seacoast
defense guns. which stand to guard
the country against the invasion of
naval force, are designed TO hurl shells
filled with high explosives against an
enemy's ships, TO penetrate their ar
NOR or vulnerable parts. and. through
delayed action of the shell fuse. to
blow them out of the water"
So. after n gun has behaved properly
with powder. the test for velocity is
imposed. and this brings into use an
instrument which performs its task
with an accuracy which Is simply as
founding. 1t is used to measure the
velocity of the projectile and is called
n chrOnograph. 1t depends upon the
fundamental law of gravitation. and is
at once simple and complicated. The
principal is certainly simple
In n general way the chronoCraph
consists of n powerful magnet. steel
rod. and n knife blade. These three
parts. with others naturally related to
them. are mounted in a structure set
mt considerable distance from the en-
placement from which the gun is to
be tested is mounted This is to OBJ
Niate jarring when the piece is dis
charged. At the top of the machine is
the powerful magnet which. when the
current is closed holds the rod sus
pended as an armature. The rod hangs
over an aperture in the base of the
instrument, and at one edge of this
opening knife blade is placed and
held back against 4 spring by another
electro magnet. The brick foundation
upon which the instrument is built
goes many feet into the ground in or
der that the greatest stability may be
obtained.
TO return to the gun two square
frames are erected on the line or fire
the first one a hundred yards from the
mu2zle of the gun, and the frames
exactly one hundred yards apart Back
and forth across these frames is a net
work Of wires, rather n cross weaving
Of one wire, which runs from the
frame to the instrument in the distant
house, and is connected with the cleo
tro magnet which holds the slender
steel rod. The second screen is like
the first. save that it's wire runs to
ih" second electro magnet. the one
holding back the knife blade at the
base OF the chronograph.
Then, with the current on. the rod
suspended. the knife blade restrained
against the spring the gun is fired.
The prOiectile pierces the first screen.
thc Wire is broken. the current is
opened the magnet is demagnetizcd
instantly ana the rod drops The pro.
jcctile speeds across the hundred-yard
space. and pierces the second screen.
breaking IT'S wires and breaking the
electric current This releases the
knife blade. past which the rod must
fan ANA. cncrgizcd by the spring. the
blade flies forward and strikes the rod.
making q minute nick upon it, BY
this time the proiecuip has flown into
the great sand butte and buried itself
and the uicked steel rod has dropped
into "a sand-dllcd receptacle. The vc-
locity has been denoted by the uuliza
tIou of simple law.
VI i~ known that % falling body fails
INIa.u and Oug.hJlt feet ODE n.e
second thirtythrec feet th. second |
and sO ON iu This ratio until 10 reaches I.
,nrIh Applying this principle t1 tha
tad. So is known that tla loot was %.
a.ty at thc level oil tine blade. $50 chat
ly measuring tine distance from the
foot to- the nick eivcs the spac
through which the rod has fallen
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