Idaho County free press. [volume] (Grangeville, Idaho Territory) 1886-current, 1911-05-18
MYSTERY OF LIGHT
Some Luminosity So Intense the
Eyes Cannot See It.
THE RIDDLE OF THE FREELY.

VIII Be- We SudI paVe Gt0US vvskO-a
out Heat and the Perfect Lamp.
The scientist set down a small black
box and impatiently pushed aside the
powerful microscope and the delicate
bOlometer. lit is most discOuragfng."
he muttered. TO have such a treasure
before ones eyes and still be- unable
to grasp it."
looked in the little box. surprised
to find nothing but "a few brilliant fire
dies. The scientist began to explain.
''In that box is the most efficient H.
luminant Known 10 a The radiant
output from one of those Insects or
responds to nearly fifty watts a can
die. while our very best artificial illu-
minant. the flaming arc lamp. gives
only two or three watts to the candle.
The light from those insects. as re-
corded by the bolometer. radiates little
il any heat. while the very best incan-
descent lamps waste more than 90 per
rem Of the electrical energy in useless
heat. Ii l could read this secret of
the insect world and make a lamp aft
er it's pattern l could produce 3S4 can
die power from the same current that
gives sixteen candle power today. Some
day the secret will be read"
The source Of all light Except the
light from f~irefies and their KIM is a
substance raised to a temperature suf-
f1cient to set up waves In he sur
rounding ether. which. when falling
upon the eye. produce the sensation
we know as light. Light waves vary
in length between n thirty-three-
Observation-Disclosures and n six
ty-five-thousandth of an inch. the first
being extreme red and the second ex-
IRENE violet. Rays of white light
have a length of one forty-five-thou-
sandth of an inch. The sun Is a great
mass of white hot matter. 1t is the at
mosphere that enables us to see light.
and outside of our atmosphere 1t is alb
solute darkness. as dark as the interior
Of Mammoth ave In an arc lamp 1t
Is the white hot particles Of carbon
floating between the two electrodes
that produce light. In the incandes-
tent lamp it is the hairpin flament in
side the glass globe that. when heated
by electricity, gives off light waves.
In gas and oil lamps light is produced
by the heated particles of carbon in the
flames above the wick or mantle.
The eye can stand without firing a
brilliance of about FIVE candle power
to the square inch of surface. The or
binary candle fame gives only two or
three candle power to the square inch.
while the sun al zenith gives 100000.
The arc light ranks next to sunlight,
with 10000 candle power an inch. and
the best tungsten flament incandes-
cents give 1000 candle power. This
means that if the sun could be chang
ed into a ball Of tungsten 1t would
throw off only 1000 candle power of
light from every square inch of its
surface, when the world would be
practically dark and we should freeze
to death in a week.
The prism shows that white light is
composed of a happy blend Of all col
Ors of the spectrum. The sun gives
the only pure white light, with the arc
lamps a close second and the metal
filament incandescents taking third
place. Sky light, such as comes from
the north on a clear day. is blush
white. Gas nantes give greenish
light. open fame yellow light and kero-
sene orange light.
By the laws Of evolution the human
eye has become accustomed to sun
light. or sky light. coming obliquely
from above. and our eyes resent light
coming from any other source. Snow
blindness. distress from white sand or
water. is the result Of violating this
rule. The upper eyelid is adapted to
shade the eye from a strong light
from above. The lower lid cannot per
form this office. 10 when a strong light
Is reflected up into the eyes It blinds
us.
The X ray has proved beyond doubt
that there are light rays which move
too fast for human eyes to register
This light p~enetrates books. wood. pa
per and v en human flesh. With the
Horoscope to assist our eyes we can
see he bones in Our arm without both
ering to remove coat or shirt. But a
man with X ray eyes would be sadly
handicapped in this world. for ht
could see nothing but solids, such as
earths and metals. and would be un
able to see a board fence at all. Be
yOnd doubt there is light so bright
that the eyes cannot see It. and to us
all Is darkness beyond what our eyes
will register.
Light rays themselves are invisible
When they To- through the ethel
alone our eyes cannot see them. conse
quently all Is total darkness. But
when they meet with the resistance OF
our atmosphere. producing heat. they
register on the retina and-behold. We
a see! AS the atmosphere thins
rapidly as we 60 upward. SO in pro
portion the air resistance diminishes
and consequently the heat of the sur
0aonQ tn urow Lose This oypla3ps