Evening star. [volume] (Washington, D.C.) 1854-1972, 1911-09-10

from q looking glass, as Il IcdllS vi tdiiS-
hitting messages or signals
Science has taken the idea, modified and
improved upon it. and the now almost per-
feet means used by all prominent nations to
transmit messages by means OF mirror and
sun rays are but the outgrowth OF the idea
of the "untutored savage, who many, many
years ago conceived the idea of making the
flashes of sun RAYS from a small piece OF look
ing glass held in the hand the medium OF con-
veying signals and messages from point to
point. Some authorities MAINTAIN that the
idea came from a period as far back as the
time of Alexander as some histories record
the fact that he piloted his fleets by signals
made BY the rays of the sun reflected from
some bright surface; but it IS generally con-
coded that the modern idea originated with
our Indians.
One prominent Indian fighter of this coun-
try. now on the retired list of our army, says
in his excellent work upon the Indians,
3Oncc, standing upon a knoll overlooking
the valley of the South Platte, | witnessed,
almost at my feet, a drill of one hundred
warriors. Their commander, a Sioux chief,
sat on his horse on a knoll little way above
me and some two hundred yards from his
command in the plain below. For more
than half an hour he directed drill which
for variety and prornptness of action could
not be excelled-I doubt if equaled-by any
cavalry in the world. There were no verbal
commands, and all | could see was an oc-
casional movement of the right arm. He
afterward told me he had used looking
glass.
Improving the Indian
THE Indian with his small piece of looking
l glass could send signal flashes distance
of over twenty-five miles. Today the civilized
world, with the idea improved upon, and
with fine instruments made for the purpose,
is able to transmit long messages over seven
times as far The instrument used IS called
Telegraph, or sun writer. Various names
are given to this instrument such as hello
graph, heliotropc, and heliotelegraph; but
the principle is the same, the name varying
according to the peculiar pattern or the
country where the instrument IS used.
The Photograph may be described as an
: instrument by which rays of light are re-
fected from highly polished mirror, mount
ed on tripod so as to throw the resulting
flash on any desired point within the field of
vision. The signals are produced by causing
the reflected rays to appear and disappear
or be obscured, the intervals OF appearance
and observation being varied IN length SO as
to produce the combinations of long and
short flashes.
This is done in two ways. In the first of
these, known as signaling by appearance,
the reflected beam, or flash, is obscured
from the receiving station, except when
message is being transmitted, the flashes
then giving the signals. In the second meth
3D. or signaling by observation, the flash
is kept continually on the receiving station
and obscurcd only for intervals, when form
ing letters. The latter method is the one
used by the army signal corps.
1t sometimes is necessary to mount two
mirrors upon the tripod, the position of the
sun with respect to the direction in which it
is desired to signal making this necessary.
When the sun is in front of the sending sta
ton one mirror is used; but when behind
the station two are used, the rays being re-
fected from one mirror to the other and
thence to the distant station. a metal
screen that opens in the middle is mounted
on a tripod and is placed SO as to intercept
the RAYS of the sun before they strike the
i. mirror. BY this screen, causing it to open
and shut, the suns rays are thrown upon
the mirror and off it, thus making long and
short flashes, which are as easily read by ex-
perts at the receiving station as the click of
the telegraph instrument by a skilled OPP
orator. The Photograph is also used in de-
filming exactly distant points for large sur
veys, as the triangulation of large tracts of
country. 1t was used for this purpose by
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