Evening star., 1898-06-04
LOSS OF VISUAL ACUTENESS.
Reasons That Tend to Make Children
Need Glasses.


Need Glasses.
Frcm the jewelers. Weekly.
1t is interesting to compare the visual
acutenesS of the normal eye before and
after the effect of some purely physical
cause, that may be within the realm of
either nature or civilization. Taking a few
instances of each for illustration, will cite
from nature first. 1t is well known that
severe illness greatly impairs the acute
ness of vision of an otherwise strong eye.
Almost the first thing a convalescent will
do is to call for book or newspaper to
while away the tediUm of the sick room.
Unless warned not to try his eyes too
much, he is apt. through forgetfulness, to
overtask his accommc cdative powers or in
Jure the already weakened ciliary muscle
When the rest of his body RECEIVERS its nor
mai strength the eye continues weak. After
straning the eyes more, in the vain hope
that his sight will improve, the person. if
ne is wise, will consult experienced help; if
otherwise, he will pick up the first pair of
sIcctac!es available, regardless of whether
they shouli be too strong too weak for
his eyes Should he finally go to an op-
tician, the latter will often find ii difficult
to fit glasses satisfactorily.
Other natural causes that affect eyes are
wind, dust, light and heat, when excessive
Eyes otherwise good enough become weak
L
be due to an error of refraction, and under
most conditions the accom- nlodative power
OF the eye is strong enough to overcome
the error. But under such atmospheric or
climatic conditions 1 have mentioned
the accommodation is lessened and the
eye cannot find relief. except by the use of
glasses They should generally be convex.
Having mentioned those losses of visual
acuteness due to natural causes, next in
order are causes produced by civilization
AT the outset l will say that if the patient
We're TO change his occupation and take
plenty of fresh air and exercise, the optic
ian's service might never be needed, but
these ifs are in the way. and are not to
be got rid of by the average individual
Take boy from the country, bring him
to town and place him at clerical work,
writing, perhaps, all day and into the
Fight. Put him behind a counter, and le;
him stand all day with one hour free out
Oh twelve or more, or let him sit at work
bench, following a trade that keens his
eyes fixed steadily. hour after hour twelve
or eighteen inches in front of him. Take
this same youth with hitherto good eyes
and bid him use them day in and day out
reading for profession or let him occupy
lis time in dimly lighted room or bend
oven desk beneath artificial light all the
time l might go on giving instance after
instance, without particulariZing any call
ing as more harmful than others to the
eyes.
Is 1t wonder that the children of this
generation are wearing glasses along with
their grand sires? Old age is no longer the
reason for wearing glasses In nine cases
out CT ten the young man needs a convex
glass to assist his overtaxed eyes in full
filling their duties.
In addition to these causes of weakened
vision. it is hardly Necessary to mention
the common evils of tobacco and alcoholic
stimulants. Again. if the strong constitu-
ton or boy cannot save his eyes from
their thousand and one uses, how can frail
women escape? The ever increasing army
of women workers in shops and offices. and
the new avenues Of employ yment opening to
them, swell the number of spectacle wear
ers. 1t has been my purpose to point out
that 1t is not the serious and very plain er-
rors of refraction that cause the most of
an opticians patronage, and he must often
attribute the loss of visual acuteness to
other causes.