Evening times-Republican. [volume] (Marshalltown, Iowa) 1890-1923, 1908-11-05

light similar to the ones illuminating
our city streets and stores. These pow
erful lights are so enclosed that the
light rays may be concentrated by
means Of mirrors until they are nearly
parallel For this purpose a parabolic,
or conical curved mirror is used.
Some remarkable claims have been
made as to the range of searchlights,
one authority stating that the beams
Of light can be seen one hundred miles
away when weather conditions are right.
The record seems to be held by the
navy When the Newark" and the
charleston We're lying in the River
Platte, in the vicinity of Montevideo,
Uruguay under exceptionally good con-
ditions of the weather and clouds, sig
nails were exchanged between the two
vessels when they We're lying sixty-f1ve
miles apart. A good searchlight viii!
have range of three miles that is to
say, an object three miles away from
the light will be brilliantly and dis
tinctly illuminated. Not long ago test
was made at the Brooklyn navy yard
of one of their powerful lights intended
for use on shipboard. The shaft of light
was turned in the direction of the
Times building, approximately three
miles distant. and while the observers
in the tower at Brooklyn could not see
any one on the roof of the Times build
ing, a man stationed there. looking at
the searchlight, was daZzled by its bril-
liancy. At one time the light was
turned on a point about the same dis
lance from the tower. but in the direc-
ton of Flatbush with similar results.
A thfrty-inch protector on the summit
of NJ. Washington is used to show the
tourists the beauties of the surround
ing mountains. When turned on the
Lizzie Bourne monument, 1000 feet
away, the monument looms up sharply
from the background.
The searchlight attains Its greatest
usefulness in the navy during actual
service. While lying at anchor on
dark night, with the enemy's ships
somewhere in the vicinity, these great
lights are worked constantly, sweep
ing the horizon, stopping now and then
to investigate suspicious objects. Then
too, the navy makes use of the pro-
jectors in signaling from one ship to
another. Uncle Sans ships are. in the
main. equipped with thirty-inch pro-
iectors. Some Of the vessels notably
the Massachusetts, are equippedt WITH
projectors. There are
a few siNty-inch searchlights in use.
The New Hampshire is equipped with
two siNty-i inch projectors and the
Connecticut with one. Some idea Of
the size of the large projectors may
be obtained from considering some OF
the data on a siXty-inch protector
which weighs 5000 pounds, and re-
quires for it operation about 10 l-S
horse power Both of the carbons are
cored The upper carbon is ~ inches
in diameter, the lower Il inches. The
lighting power is about 100000 cam
die power
Each ship is not equipped with port
able searchlights, which are at all
times available for use in connection
with landing parties. 1t is expected
that. in the future, these outfits will
be of valuable use to such parties.
They have never been given an actual
trial in warfare, as they have only
come into use since the Spanish war. !
Each of these portable lights consist |
of two parts. On one carriage Is
mounted the generating apparatus, and
on the other is protector and drum
on which is found long insulated ca
bles. The generator is driven by
little gasolene engine, Of six horse pow
err, and the electricity is transmitted to
the searchlight thru the cables uncoiled
from the searchlight carriage drum.
Before a searchlight is accepted at
the Schenectady plant of the general
electric works it is tested for it's range
by comparing a light given off against
that emitted by a standard Shuckers
protector. A test is also made on the
mirror to see that it is truly parabolic.
If the results of these two tests are
the light is accepted.