Gilpin observer., 1912-06-13

abled before she came within the fighting range
adopted by powers.
In target practice all the rules aim at the
reproduction of the conditions of actual battle and
every effort is put forth to accomplish this end
Some time before the practice is to be held, each
ofhcer whose post requires an advance knowledge
OF the work to be done receives book of rules
for that particular practice. This book is consid
cred to be confidential document, the contents
of which are not to be revealed to persons outside
the service. The first page IS perforated and
bears number corresponding to that on the book
Itself The recipient signs receipt on this page
and 1t is torn out and retained by the navy depart
ment. This book therefore. is held under signed
agreement not to reveal what its pages contain.
The practice this year included spotters test
target shooting by individual ships and by divi-
sions, torpedo firing by battleships and by torpedo
boats. The sunken battleship San Marcos. for
merly the Texas, which is being used a naval
mark, was the target in the case of the spotter's
test 1t is reported that later her lattice frecon
troll masts to serve targets in order to learn
how long that type of mast will stand when under
fire. Each battleship has one or more spoilers
These are the men who occupy the fire control
baskets on the lattice masts and watch the fall
of the shots. They are expected to be able to tell
almost instantly how far over or under the mark
the shells struck and telephone 1t to the plotting
room, down In the bowels of the vessel. They sup
plement the mechanical range finder. and assist
the plotters below working out the ranges to cor
rect any differences thus indicated The discrep-
ancy between the range obtained mechanically
and the observation of the spoter is considered to
indicate the strength OF the powder charge and the
supply of powder is varied accordingly.
In the spoilers test the range was known to
the umpires. and the guns were fired at prear
ranged elevations, ranges. The spoilers were
expected to tell what the errors. discrepancies.
were. Their estimates then compared with
the known ranges
In individual practice each ship is limited to a
certain number of shots and 1t has Its own target,
The scoring is based on the number of hits per
minute per gun. 1t has been found that the gun
In land fortifcation may be expected to
average one hit in three shots at moving target
1t is. therefore considered that ship that can
make 30 per cent. of hits has made perfect
score. for the floating gun platform not only is
unstable but is moving while the fortifcation not
only has nxed platform, but there are oppor-
tunites for increasing the length of the base OF
the range finder.
The ranges obtained by taking two sights
at the mark from different points whose distance
apart is known with preciseness. The angles OF
the two sight lines when the sights are focused
known length OF the base line. will show its exact
distance. The forti6caton has advantage over
a vessel also in that the garrison plot out
of its ranges in advance. The range finder
on a battleship is approximately sixteen feet long.
This is the base line upon which the calculations
are worked out Taking this into consideration.
the capacity for making a hit on target more
on the part OF all who manipulate the fighting
machine.
As the ship Is not only limited In the number
of shots TO be fired, but in u measure to the In
terval of time In which they may be sent In search
OF the target, II vii be that without prelim'
mary practice OF some kind the records which
have been made would be impossible. 1t is not