The Dakota chief. (Gann Valley, Buffalo County, S.D.) 18??-1913, 1895-01-03
CHEAPEST OF AL LIGHTS
That shown by Firefiies = Scier,,
Experiments in Way of Imito.:-"ht

That SHOWN by Flrefies = Scien,,o
Experiments in Way of INITIATING
One of the prettiest sights of a sm'
mer evening In the country Is a mead.
covered with a swarm of ~flittiny g."
flies. Many intensely practical na'
pie have laughed at any suggestions
that this freely light could be utjli1as
in any way by man. Yet scientis,'
have long been at work on the problem .
and one of the number, Secretarn
Langley. of the Smithsonian Insti,,,
ton, has arrived at some startling con.
illusions. The light shed by these in
sects, says the Boston Journal. is fl.
most economical illuminant in ,bo
world. 1t has no waste and no eyor
running meter. Moreover, it is lon
times as cheap as gas, which meaN
that n pays a dollar for a cenvs
worth of light, and even with elan
tricity the waste is enormous. With
the freely there is no waste by the pro..
duction of heat. This may seem ratbor
strange to those who inseparahly con.
nect a light with some degree of heat
manifestation, and this cold light,
If such it might be called, would be M.
culiarly adapted to a hot summer even.
ing. 1t Is probably simply the result
of n chemical action which produces
n phosphorescence. 1t is produced al
Observation-Disclosures Of the. cost Of
energy represented in a,candlG flame.
and Is supposed to come from the slow
combustion of a material secreted by
the nervous organism Of the insect.
The temperature of the light-giving or.
CANS is the same as that of other parts
of the body.
In Professor Langley's experiments
he took the insects, kept them in the
dark all the time, preserved their eggs
Il long time, and ground the dried sub.
stance to powder. In all these cases
the application of moisture produced a
light, proving the chemical origin Of
the phenomenon. To produce a light
of equal brilliancy artificiallY would
require Il temperature Of at least 1000
degrees. The most brilliant of the $50
varieties of animal life capable Of
producing Il light of this character is
the "cucujo," the famous freely of the
tropics. Thirty-eight Of these yield one
candle power. The natives of Cuba
confine them in paper lanterns, and
they have been used to take photo,
graphs by a two-minute exposure of
bromide plates. These insects. or
beetles. to speak exactly, were used by
Professor Langley in experimenting.
They begin life As a grub. and are va
riously called ''skip-jacks," or "sprins-
tails" Damp evenings seen to be the
most favorable time to observe their
habits. as Then they shine most brill
iantly Nature having produced this
most economical light, which in the
most exaggerated instance cannot be
made TO affect the most delicate Their
momcter. seems To laugh ut the feeble
efforts of man Ia follow her plan. Il
is true that the GciSSlcr tube. n play
thing of the laboratory. will i'triuce
light without heat. but it is inca yaNe
of practical production. Scientists be-
lievethat ere long the secret of t'ie won
derful light. which las Been proved III.
like the luminous calcium sulphide
paint of commerce, will be discovered.
with q result as revolutionary in the
world of illumination as that caused by
electricity.