The Lambertville record. [volume] (Lambertville, N.J.) 1872-1968, 1884-04-02
COLOR BLINDNESS.
Numbers of Railroad Employees Affected
WIKI this Trouble of the Eye.

For several years past oculists in this
city and elsewhere have interested them.
selves in the peculiar physiological anomaly
commonly known as color blindness to
such an extent that, while the real cause
has not been absolute developed, yet, in
countries like the United States aud Eng.
land, where the railway interests are SC
large and the lives of the travelling public
are virtually in the hands of one or two
men, the application of scientific knowl.
edge has been a great protection. In a
recent examination of over ten thousand
engineers and signal men employed by the
Pennsylvania R.ilr rad Company, Professor
William Thomson, of this city found that
ten per cent. were deficient in the full
amity of vision. Until within u very recent
date the Philadelphia and Reading Rail
'oad Company entrusted the lives of thou
sands of its patrons 70 men who was
totally blind in one eye and had only one
fourth normal vision in the other. The
man for years had charge OF signal tower
on the. Germantown branch. which govern.
ed the running of over q hundred trains
daily, carrying thousands o; people TO and
from their homes in the SUBURBS. Not
withstanding the lesson taught by this case
the Board of Managers of the road have
failed to note the Importance of having au
expert to protect the public from accidents
and themselves from litigation. In this
country, where trains are run ON the
- block svatan, e 10 moi 80 avail ;,,,No,.l
snce that signalmen and engine drivers as
we'll as all other train men, should be able
% distinguish between q red and green
light at once. 1t is discomforting to reflect
that according to statistics obtainable, the
chances are only twenty-four to one against
travelling in a train in charge OF color
blind driver, or of having, through the
defect Of the vision of tile signal man. an
accident where hundreds of lives may be
lost. Forty men in every thousand are
color blind. That is, they cannot tell the
Inference between a scarlet or dark green
solor, or a red from n green light. 10 a
person totally color blind there il no differ
ence in color between a strawberry and III
leaf They see form, light and shade
nothing more. Partial color blindness is
common. Some affected by it are blind to
red, others to green and u few to violet
hat is, to one or more of the three primary
,olors, and as much of it or them as may
enter into any combination of colors The
cause of this Is the insensibility of tho
retina of the eye to certain of the rnys of
Which pure white sunlight is composed. II
may be assumed that red, green and violet
nre the colors from which all others are
produced by light alone. These rays and
their compounds travel Mt different rates
and in different wave lengths, affecting the
retina of an ordinary eye SO MS to make
perceptble variety of hues. Dalton, the
great English scientist, was color blind for
red, and some amusement was afforded by
his wearing the red gown of q doctor Oh
civil law at Oxford in the open streets in
complete Inconsistencies that he afforded
4 remarkable spectacle to the ordinary eye
Of the average beholder. His great scien
iic reputation gave the name of Daltonisn
to the defect. The poet Whittier is said t.
be color blind and the Duke of Newcastle
who SO recently visited this country, cal
only recognize the riIe fruit of IA cherr,
tree by its form, he beng color blind fol
red. Philadelphia Press.