The daily journal. (Salem, Or.) 1899-1903, 1903-06-12
Many are at Least
Partially Color
blind
Red the Hardest Color TO Dis
tingniSh--Nature Uses
Stripes and Spots for
COncealment
(Pearson's weekly)

iSui olue anu yellOW paint becomes 10
all intents and purposes invisible, at
least at any considerable distance.
Six guns and their llmbers so
painted and streaked with the three
primary colors. as they are called.
were placed on the Fox hills at Alder.
shot, and a number Of artillery OH.
GERS invited to locate them.
The distance was only 5000 yards
a mere trife In actual warfare-and
the officers were armed with the best
OF field glasses, But 80 perfectly did
the painted guns harmonize with the
natural background that no one was
able TO pick them out.
Some horse artillery sent forward
to engage the guns never saw them
at all until they had reached a point
barely 1000 yards away
Many animals OF all kinds take ad.
vantage OF the way in which sight.
especially human sight, confuses col.
ors The leopard, living In low thlckets
where the sunlight, broken by leaves,
falls in patches on the soil beneath.
has skin blotched with black spots.
making the creatures practically in.
visible except at very close quarters.
Among fish. insects, reptiles and
snakes, hundreds OF species are
known OF which their markings rem
der them practically invisible In their
natural surroundings.
Partially Color Blind.
Recent researches have shown that
a far greater number OF people are al
least partially color blind than wal
formerly imagined. The commones
case is a deficient perception OF red
blue and violet. often partially colo
blind persons name these quite cor
rectly. but they are unable to dis
tlnguish between rose red and blush
green.
I A few years ago DR., Fayre examined
the color perceptions OF 1000 railway
officials. and found that 9s we're quite
color blind, and a number more par
! TALLY so.
Women, Il may be mentioned, arC
hardly ever color blind. but why this
is so no one pretends TO explain. Az
ter any severe nervous shock. you
will be very likely TO find that you
have become temporarily color blind
Your perception OF green light has
probably gone. at least partially
White objects will then appear "a
you OF a reddish purple, and green oh
jects TO be very much duller In hue
than ordinarily.
Anyone can make him or herself
color blind by wearing a pair OF ruby
red glasses. The prolonged action OF
red light on the eyes ends by trims
out the nerves which receive red
light. Consequently, when the glass
es are at last removed. rainbow ap
pears 20 have only two colOrs, yellow
and blue.
Many people have found II dlfhcult
10 believe in the possibility of the ex
traordinary attitudes assumed by gal
looping horses or other creatures In
rapid motion, as shown in instantan'
eous photographs. Here we have an
other instance OF sights which We
that is. our eyes-are unable 20 grasp
The Positive image.
The fact Is that though the eye
selzes a view with extraordinary
rapldity. that view docs not pass away
at once from the retina. What scien'
lists call the positive image persists
for a perceptible period Of time. and
after Il is gone Il Is replaced BY a
negative image-that Is. the same
view. but IN colors Complementary 10
the positive lmags. Thus. II the sight
seen vas a regiment OF scarlet clad
soldiers. the negative image would
show these soldiers in a greenish
blue hue.
SO the impression We get when
looking at anything is actually made
up Of a number Of different views Of
the object, whereas the instantaneous
Photographic plate gives US only one
Of these views. and hence look 70 Us
unnatural
A small and simple experiment can
be tried by any reader which viii go
far 10 convince him or her what
debt We owe 20 color and what good
thing IL is we have sunlight which en-,
abies our eyes 20 take advantage Of
the beautiful hues Of nature. Make