The Seattle post-intelligencer. [volume] (Seattle, Wash. Terr. [Wash.]) 1888-1914, 1898-05-19

Ever since the bornhardmeas as Manila
the world has had IFS azfention turned 10
the fac. that the accuracy a u1srksrnaEa-
ship OF the guns IN the navy Of the United
States Is something wonderful
TIE officials Of the navy have for long
time belseved that the accuracy Of the
Ansrscan guns were one % their best
points % superiority. bat II was not I'LL
the late engagement that i was proved
beyond a doubt that their method Of tfEi-
ing the correct range Is excellent.
The accuracy % the modern American
riaed guns Is oEe of thu wonders OF mod
EN- engineering. In an experiment, tried
several years ago two shots fred from
thu same gun fell within thirty yards ot
enc another after travegSiaz a distance
OF twelve miles. II IS dedueed from this
experiment that Il a modern rife Is laid
upon a target with due allowance Tor the
effect OF the wind. the shot viii ina the
mark
Unless the distance Of the large. Is
known the range and therefore the cor
rest elevation OF the gun cannot be de-
tsrmined- The exact determination Of the
distance OF moving object Is problem
that has worried the gunner ever since
the day when round shot was first thrown
from the sides of wooden ship.
This determination was CT great import
ance in those days. bu. now that ex-
pensive charges. costing. for the Large
guns in the vicinity Of Si.S0. are used. the
problem becomes of much more import
ance. Then, too. the Importance OF a
lucky shot cannot be oyerestimated in
these days.
In former years tho determination OF
accurate range was a matter OF mere
guesswork. The gunner would assume
distance. elevate his gun to the proper
angie and then fire. If the shot fell short
OF the mark, he would elevate his gun
more for the next charge. and vice versa.
This answered the purpose fairly well
IN those days. but now that sixty-ton guns
ara used with heavy charges, the neces-
s.ty OF accurate fire IS imperative.
The device used IN our navy and by
many other Bavies OF the world is the in
vention OF Lieut. Fisk, OF the United States
navy, now with Dewey's feet
The Fisk range finder - based upon the
well-known principle OF land surveying
with the transit. When an unknown dis
lance is wanted, such as the distance
across river. base line Is measured
along the bank. and the angles which this
line makes with a mark on the opposite
bank are measured by the transit With
this data the distance across the river
can hs determined by the principles OF
trigoaometry.
Applying this 10 the range finder. a base
line is carefully measured between two
over each point range finder is perma-
nently set. II the telescopes OF the two
instruments are placed upon the same OBJ
5ect at the same time and the angle re-
corded. the data necessary TO compute the
distance is given
In the din and hurry OF sea fight,
however. II would be difficult for even the
caimess ofiicer to make the necessary
mathematical calculations, and, moreover,
as the ships keep moving the angles keep
changing. and the distance between the
ships Keeps changing. In order to make
the determination OF the distance auto
matte. Lieut.. Fisk has placed his trans.s
IN the circuit OF a wheatstone bridge and
caused their change OF position to record
the distance OF the object on the gradu-
ated scale OK delicate gaIvancmeser.
All that was now necessary was for the
observers at the two range finders to keep
the cross hairs of the telescope uron this
same point OF the ship at the same time.
and the electric current Translated the
angles into distances and recorded them
by the movement OF needle over an arc
graduated into hundreds and thousands
OF yards.
ohe or these galvanometers Is placed In
the coming tower and one at each end Of
the principal guns OF the ship. The one
ra'or OF each instrument has a telephone
tran smitfer opposite his mouth, go thai
ne Kept tn constant communication
WITH the other operator. II the OPERATORS
were not kept in constant communication
serious defects would occur In the raad.
ing OF the range finder.
mis- is the first device OF the kfnd ever
invented. and is practically the only ara
or any USE II IL used in the nay;es ~
several OF the powers, and # is consid-
cred BY many officers TO be one OF Tho
most necessary fittings of the modem
cruiser. .A