The southern sentinel., 1903-09-18
SIGHT DELuSIoNa
People Deficient in Color p.
at Times Receive Singul.,
ular Impression.

OooA - queer failh,
the whole human race is subisr
to an extent. 1t has been dis
that an ordinary cannon, ii eo,.
over with blotches Of red, blra ~ -
low paint, becomes to all intsr.s
purposes invisible, at least at a,s
siderable distance, says the Pbil,sa'as
Press.
Six guns and their limbers 50 ,..
and streaked with the three M
colors. as they are called. wera .
on the Fox Hills at Aldersbot =.
number of artillery officers ipy;,.s
locate them.
The distance was only 3O0o ,,,.
a mere trifie in actual warfare-s,s.
officers were armed with the best "a
glasses.
But SO perfectly did the painted -.
harmonize with the natural baekm..
that no one was able to pick them
Some horse artillery sent forms
engage the guns never saw them - :
until they had reached a point 49,
1000 yards away.
Many animals of all kinds tab. .
vantage of the way in which sieht .
pecially human sight, confuses colon
The leopard, living in low thieas
where the sunlight, broken BY l.r
falls in patches on the soil beneath q
a skin blotched with black spots M
ing the creature practically inyidR.
except at very close quarters.
Among fish, insects, reptiles -
snakes. hundreds of species are Inn
Of which their markings render d.
practically invisible in their nstml
surroundings.
Recent researches have shown thss.
far greater number of people are I
least partially color blind than nj
formerly imagined.
The commonest case is defcientps.
ception of red. blue and violet Ola
partially color blind persons name tha
quite correctly. But they are urahs
to distinguish between rose red -
blush green.
A few years ago the color perceria
of 1000 railway officials was examinsl
and it was found that 9S were quite al
or blind, and a number more partiIk
so.
Women, 1t may be mentioned. n
hardly ever color blind. but why thhh
SO no one pretends to explain.
After any severe nervous shock ~
will be very likely to find that ~
have become temporarily color blind
Your perception Of green light h
probably gone. at least partially. Win
objects will then appear to You Of ;
reddish purple. and green objects tch
very much duller in hue than ordinarily
Anyone can make him or herself ter
porarily color blind by wearing pek
Of ruby-red glasses.
The prolonged action of red light q
the eyes ends by firing out the nerEa
which receive red light Consequenth,
when the glasses are at last removed
a rainbow appears to have only tv1
colors, yellow and blue.
Many people have found 1t difficult q
believe in the possibility of the extran'
binary attitudes assumed by galloplnl
horses or other creatures in rapid -
ton, as shown in instantaneous phctne
raphy.
Here we have another instance q
sights which we-that is, our eyes-sl
unable to grasp.
The fact is that though the eye sen
a view with extraordinary rapidlu
that view does not pass away At oad
from the retina.
What scientists call the positive -
age persists for perceptible period 2
time. and after it is gone it Is replace'
by a negative image, that Is the 81
view, but in colors Complementary 2
the positive image.
Thus, if the sight seen was res1me
of scarlet-clad soldiers, the neeanN
image would show those soldiers u
greenish blue hue.
So the impression we get when io's
ing at anything is actually made up
q number of different views OF the g
ject, whereas the instantaneous pnosp
graphic plate gives us only one OF the
views, and hence looks to us unnatul.
A small and simple experiment can
tried which will go far to consls0
him or her what debt we owe to cor
and what a good thing it is We nss
sunlight, which enables our eyes '
take advantage of the beautiful ~
Of nature. 81
Make a room quite dark. ana as
burn some carbonate Of soda IN y
fame of Bunsen gas burner.
It will burn with an orange yel'o'
light sufficiently strong to illumine
everything in the room. but you y.
realize with a sudden shock that, Dflsl
though the light is, all distincfions
color have vanished. Only light -
shade remain.
A crimson carnation, blue violes'
red tablecloth, yellow blind-aii lo'
gray or black or white. The faces
those present look positively repuisi"
for all natural color has disappeareo'
No other experiment will so well co.
vince those who have witnessed II 90
great loss would be that of our se1'
for color.
A Cows Queer Act.
The forco of bobif uos very fOfc1Dl