Idaho semi-weekly world. [volume] (Idaho City, Idaho Territory) 1875-1908, 1891-04-21
PHOSPH0R ESCENCE.
THE LIGHT WHICH tLLuMlNES WITH
OUT CREATING HEAT.

There is no subject which the re-
| searches of scientists have more com
pletely failed to elucidate than that of
the cause of animal, mineral and vege-
table phosphorescence-the light which,
unlike all other lights, illumines with
out either consuming or giving out any
perceptible heat. The ocean is the great
storehouse of phosphorescent light On
its surface myriads of noctiluce Qittle
creatures Just visible to the naked eye
are often seen lighting the waves for
miles, and presenting wonderful effects
| when the water is broken by the bow OF
a ship or the oars of boat. Persons who
have passed through stretch of water
crowded with noctiuce say that the
light they give dims that of the stars,
and makes the sea look as though 1t were
a vast heaving mass of metal at white
heat.
The intensity Of the light is explained
by the immense quantity of the little
animals, which are computed to number
thirty thousand or SO to the cubic foot
Bathers in waters where they abound
have often been amazed to find, on
emerging, that their bodies are rendered
luminous by the noctiluc8 that cling to
them
A kind of sea slug that is met with in
the Mediterranean and the Pacific emits
light from certain spots in the body. 1t
is capable of being kept in an aquarium.
and there are usually some specimens in
the famous one at Naples When dis
turbed or swimming the light makes it
look like flame in the water
PYRoSoME.
The most splendid of the many lumi-
nous inhabitants of the sea are the pyro-
some. At night they look as though
made of glowing white hot iron, diffus
ing so strong light that other fishes are
rendered visible when they happen to
swim within hesphere of their radiance
A distinguishing feature of the pyro
soma is the variety of tints that it gives
forth-orange, green, azure, blue, white
and various shades of dark red having
been all noticed by various observers.
A tiny kind of shark that is met with off
America is a noted light giver. Speci-
mems captured and taken into a dark
apartment present an extraordinary spec
tacse The entire surface of the head
and body emits greenish CLEAN that is
constant, and is not, as in the case of
most of these luminous inhabitants of
the sea, increased by friction and agita-
ton.
The smallness of the fins of this fish
show that it is not an active swimmer,
and the assumption is that its light is
useful in attracting its prey, on the prin-
ciple of the torches used by many saw
ages in fishing Several kinds of crabs
are luminous. One named the sapphirina
is noted for the intensely vivid character
of the light that proceeds from it, So
brilliant is it that it does not need dark
ness to make its presence known, but
corruscates blue, purple, green, gold and
sapphire rays in full daylight The
presence of school of mackerel is often
indicated by the phosphorescent CLEAN
which these fish produce. Fishermen
often descry them at a great distance by
this light, and hasten to surround them
by their nets. 1t is thought that mack
light, as after they are captured a gleam-
ing fluid is noticed running off their
bodies, and sometimes covering the hands
of the mea who toss them from the boat
FIREFLIEs.
1t has been urged that the poet was
guilty of an exaggeration in describing
the tireflies as giving sufficient light to
be of any service; but the accounts of
travellers in South America, who tell us
that the natives light their path while
Journeying by a couple of these insects
tied to their feet, show that he was
speaking qrte within the bounds of DOS
slolllty. At evening entertainments in
that part of the world it is customary
far ladies' to decorate their hair and
dresses with firehies, confined by deli.
cate silken threads.
The natives of Vera Cruz do quite a
large trade in firefies, which they catch
by waving blazing coal at the end of a
stick. Tho insects fly toward the light.
and are captured in nets. The fireflies
OF Northern America differ from those
Just described in the fact that they emit
thelr hight in capricious flashes, instead |
OF with a steady, uniform glow. This
popularity has gained for them the name |
OF lightning bugs" Their light is very
similar to that of our glowworm. A |
story is told of some French peasants
VINO were returning home one night and |
saw meteor fall through the sky in
front OF them; about half mile further
on they came to glowing mass in a
ditch and rushed away terrified, declar-
ing that a star had fallen upon the earth
and was burning it up. On investigation
II was found that this burning star was
nothing more uncanny than o mass of
frogs eggs that had developed nhosphor-
escence.
Several varieties of the vegetable KING.
dom are luminous in a greater or less
degree One of the fungi, which is not
at all uncommon on the walls of damn
dark mines, caverns, etc, occasionally
emlts sufficient light to admit of the
reading Of ordinary print by it. The
emission OF light from the common no
'ato "hen IN state of decomposition is
sometimes very striking Several of the
indian plants and grasses are also lumin.
Gus and it is said that in 1915 the noun
taihs near Syree were nightly illuminated
by Their means. The root stock of n
pant from the Ooraghum Jungle, sup
posed to be an orchid, possesses the ne.
euliar property of becoming luminous
"heh wetted, while, when dry. it is
quite l1SterIeSS The bair, ,l -