The Vancouver independent. (Vancouver, W.T. [Wash.]) 1875-1910, 1882-03-02
COler Sense In RaiIr0aders.

General manager Frank Thomson, of
the Pennsylvania Railroad Company, has
issued instructions under which exami-
nations will be made by the respective
superintendent on each division of the
road as soon as practicable OF all en-
ployes who are required to use or be
governed by signals. Pers~ MS will not
be appointed to such positions until
they have satisfactorily passed examina-
tions with regard to their vision, color
sense and hearing.
The method of examination was de-
vised by VIM. Thomson, M. D., Pro-
lessor of Ophthalmology in the Jefferson
Medical College, in conjunction with
special committee of the Society of
Transportation officers of the Pennsyl-
vania Road, and was accepted by the
railroad company. The instructions
have been so plainly laid down that it
is not necessary for skilled practitioner
to conduct the examination, but en-
ployes failing to come up to the standard
have the privilege of undergoing special
examination by Prof. Thomson, who
has been retained by the company as an
expert.
The entire method has been submitted
to practical experimental test extend
ing over nearly 1000 men, employed as
conductors, engineers, fremen and
brakemen, and the results have satisfied
the committee that the system proposed
may now be put in force with confidence
in its practical utility. Inquiry devel-
oped that there were in the service of
the Pennsylvania Railroad, of the 1888
men examined, 246 men deficient in the
full acuteness of vision, 30 absolutely
color blind and 81 defective in hearing.
In one of the reports an examination not
included in the instructions from the
committee was made with colored flags
and colored lights by night, and ID men
failed to be able TO recognize them from
total of "a, who were color-blind to
the test used for its detection.
Investigation has led deep thinkers to
the conclusion that one man in twenty
five will be found color blind to a degree
to render him unfit for service where
prompt recognition of signals is needed,
inasmuch as blindness for red and
green renders signals of these colors in
distinguishable. 1t is a fact in physiol-
ogical optics, however, that yellow and
blue are seen by those color-blind for
red and green, and that yellow-violet
blindness is so rare that it might lead to
the use of these yellow and blue colors,
in preference to red and green wherever
possible.
In considering system which would
enable any intelligent person to cond"ct
the examinations as to the strength of
vision, color sense and hearing, noting
his observations on proper blanks and
submitting these to the expert for iudg-
ment, it was found necessary: L. To as
certain whether each man possesses
sight sufficient to see form ut the average
distance, and range of vision to enable
him to see near objects well enough to
read written or printed orders and in
structions. 2. To learn if each man has
color sense sufficient to judge promptly
by day or night, between the colors IN
use for signals.
According to the instructions formu
lated for the examination and issued by
General Manager Thompson, the follow
ing apparatus will be used A card con-
tanning letters of graded sizes for testing
distant sight, frame for supporting
print to be read with graduated rod at
tached for measuring distance from the
eve while reading; spectacle frame for
obstructing the vision of either eye while
testing the other; watch with an hour
tick for testing the hearing, and an assort-
ment Of colored yarns for testing the
sense of color. This last consists OF a
frame containing forty tints of red green
and rose colors. Persons will be re-
quired to select given color when it is
named, to match test skein handed to
them and to undergo an examination on
thts noint which will calculnte their
color sense to nicely.