Madison times. (Tallulah, Madison Parish, La.) 1884-1???, 1885-07-18
COLOR BLINDNESS.
Inability 10 Distinguish Red che Most
Freauent Defect.

The most frequent defect IN color
blindness is the inability to distinguish
red. A distinguished professor in an
English university once wore scarlet
gown through the streets, much to the
of many who saw him. On
being asked by friend what appeared
to him 70 be the color of this robe, he
answered, pointing to some evergreens
near by: at seems to me to resemble
those as closely as possible" The next
color most frequently mistaken for some
other is green. The Importance OF this
defect is estimated by the frequency OF
its occurrence. If it occurs only once in
10000 persons, It is of course of less i'm
portance than if happening once in 100.
Men are more frequently affected with
this defect of vision than women. The
defect, when it is congenitai, as 1t is In
most of the cases under the observation
of physicians, is incurable. 1t is some
times induced by immoderate use of to-
bacco or liquor. As many as one in
twenty-five of the men employed on
lines of travel are affected by this inabil-
ity to distinguish red from green. The
colsr blind in case of accident by travel
ON land and sea cannot readily be de-
tected because of the difficulty of tracing
the causes of the accident. One thus af-
fected can not tell red from a green
light, but one of these lights appears
darker or less bright to him than the
other.
The test of color blindness is not how
well one can name colors, but how much
he sees them. If two Letters be drawn,
one red and another green, on back
ground, person who is red blind VIII
distinguish only the green letter, and a
partv who is green blind would fail to
distinguish or see the green letter. In
other words. to the first the red color is
SUPPRESSED and to the second the green
The red blind will place purple or q
green alongside of rose color, supposine
them all to be the same shade. The
II green Dlluu Will COulOuuu thO pi"S INV
the gray with the rose color.
The test for an engineer is not to name
colors and shades of color, but to know
red as red and green as green, and tt
match red with red and green witt
green of their various shades. Four PEI
cent, of the $4,000 employees OF the Penn
sylvania railway have been found total
color.blind, and 10 per cent, more or les
affected with this defect of vision. Fiv,
per cent, of the same were found Will
Imperfect hearing. In this city lives
we'll known animal painter who is en-
tirely color-blind. He selects his colo
not by knowing the color itself, but D.
reading their names on the tubes. II
employs usually only black, brown AM
white in his work.
DIR. Jeffries, OF Philadelphia, Institute
a very efficient test of color-bllndness D
suspending numbered skeins OF worste
} of different colors from rod. In
standard colors of rsse, red, and greer
with all the various shades of these co
ors, were numbered with the odd mum
: bers. All other colOrs were numbere
with even numbers. The persons e.
. aminel for color-blindness were invite
10 match shades of the three named be
r fore as the standard, and if any so name
e were among those numbered with I'll
S even numbers it was seen at once tn
they were unable to distinguish colOr
DIR. George S. Munson.