The Anderson intelligencer. [volume] (Anderson Court House, S.C.) 1860-1914, 1894-06-20
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TORCHES OF THE NIGHT.
Insects Furnish the Cheapest Form OF
Light.
PHILADELPHIA Times.

The retirement of G. Y. Riley from
The post of United States entomolo-
gist removes from Government EN-.
ploymcnt one of the most eminent in
yestigators of the city. Science un-
der Uncle Sam auspices has done no
more important work than has been
accomplished in the study of insects.
In that branch of the animal creation
Secretary Langley, Of the Smithsonian
Institution, has made perhaps the
most picturesque scarch-relating to
the light afforded by freAics,
This light, Prof. Langley has dis
covered, is the most economical IL
luminant in the world. 1t is one hum
dred times as cheap as gas. That is
to say, there is no waste, whereas the
waste in burning gas or lamps is more
than SO per cent. In other words, the
consumer pays dollar for every cents
worth of light he gets. With cleo;
tricity the waste is less, but still enor-
nous. The FREELY light expands no
energy in the shape Of heat.
So here is what might be termed
cool light without waste. If pro-
cess could be invented for producing
it in large quantities by arti6ce, the
discovery would be Of enormous benc-
fit to mankind. Incidentally, cleo
tricity and gas would be driven out Of
use for Illuminating purposes. That
the secret will be found sooner or later
is not at all unlikely. The notion
formerly held that the light was part
and parcel of the life of the FREELY has
been exploded. 1t is now believed to
be simply product of chemical COM
bustion.
Such being the case it ought to be
practicable to produce the phenome-
non in the laboratory or even en-
large scale. This peculiar light term
ed ."phosphorescence' has received
little attention from scientists up to
date; it affords an attractive field for
investigation. The supposition is
that it is made by the slow combus-
ton Of material sccreted under the
control of the nervous system of the
insect. It is produced at one-four-
hundredth-of the cost of energy ex-
pended in a candle flame. Nothing is
lost in the shape of heat, the light
giving organs having the same temper
ature as other parts Of the animal.
More than one hundred and fifty
families of animals on land and in wa
ter, embracing tens of thousands OF
species, produce such phosphorescent
light. They yield enough Of it to il
Illuminate London, Paris and Phila-
delphia. The surface Of the ocean is
alive with luminous crustaceans, jelly
fishes, etc., not to mention innumera-
lie vegetable organisms, each Of which
-, q tiny lantern. In the depths swim
lamp p-bearing fishes. On land crawl
glow-worms and electric centipedes,
while in the air frefies and flight
ming bugs" of many kinds disport
themselves. All of this light crowded
into one place would hardly affect.a
thermometer.
The most brilliant light afforded by
any land animal is that Of the famous
frefy of the tropics known as the
"cucujo." Thirty-eight Of them yield
one candle-power. Photographs have
been printed by two-minute exposure
of bromide plates to their illumina-
tion. People in Cuba conGne them
in paper lanterns for going about the
country at night or for indoor light
ming. Sometimes they attach one Of
the insects to each foot for travelling
in the dark to serve us guide to the
path. Also they use them as orna-
ments for the dress and hair.
1t is with these 6refies that Prof.
Langley conducted his experiments.
They are beetles, beginning life as
grubs, "Skipjacks" or "spring-tails"
they are sometimes called, because,
when placed on their backs, they jump
over with clicking sound. A small
species of the same family is found in
Florida and Texas. They have two
luminous spots on the thorax and an
other on the abdomen. Damp even
ings are most Favorable to the light
giving, the object of which Is presum-
ably to attract the sexes. The young
larvae feed largely on snails, to which
their bite is poisonous. The lumi-
nous organs are developed before the
insects leave the eggs,
Now, a theory formerly held was
that these frehies stored up light in
the daytime for emission at night-as
is done by the so-called luminous
paint" Of calcium sulphide. But it
was found that they shone as brightly
as ever after being confined for ten
days in darkness. Some that we're
carried all the way from Cuba to
Havrc in the pitch-black hold Of a
vessel were brilliant on their arrival.
A more striking disproof, however,
was afforded by batch of larvae
hatched in the dark from eggs laid in
the dark in piece of rotten wood, the
young insects being kept in darkness
for the first six months Of their lives.
They shone.
Prof. Langley decided that the light
did not depend on the vital principle
of the insect. He found that the egg
became luminous on being shaken in
glass receptacle. Then he dried the
eggs and kept them in that condition
for long time. On being moistened
they shone. The dried eggs were
powdered in a mortar, but they gave
light on being moistened. The bee
ties themselves, twelve hours after
being killed by electricity, were still
luminous. So the Professor infers
that nothing more than a chemical
cobustion is concerned in the manu-
facture of this Cheapest light" He
thinks there is hope that VIC may be
able to reproduce it some day.
To make light equal in brilliancy
to that of this tropical insect we must
produce temperature of 1000 de-
grees. The frefy's lamp creates no
heat that can be detected by the most
delicate instrument. It's energy is
entirely expended in illumination.
Nature, while offering object lessons
in the art on every hand, laughs at
mans efforts to initiate her in this
field. There is a device known as