The Democratic advocate. [volume] (Westminster, Md.) 1865-1972, 1885-03-14
rne Eve. and How 20 Care for Eyesislt.

This was the subject of the eighth lecture
in the Theological Seminary course, and was
delivered in the lecture room of the Methodist
Protestant Church, on Monday evening last,
nv DIR. J. W. Herring, of this city. The at
to- .Janee was large, and much interest was
manifested in the lecture. Large diagrams
and blackboard drawings were used through
out in illustrating the various points treated.
After some preliminary remarks IN regard
to the importance of vision as one OF the spe-
cial senses. and It's near relation to our com
fort and usefulness In life, and some general
reflections in respect to the physiology OF the
visual act. the lecturer took up the anatomy
of the eve and its appendages, speaking first
Of the orbit. its construction. shape, and the
direction of its axis, as affording the widest
range Of vision consistent with the opposite
action of the eye, which is binocular vision,
or our ability to recognize but one object, al
though a separate image Is made IN each eye.
The muscles of the eye were then shown,
and their anatomy and uses clearly pointed
out: there being four straight muscles, which
take hold of the eye-ball at about equal DIS
tances from each other, and by the action OF
which all the movements OF the ball, IN, out,
up and down, are made. Also two oblque
muscles, by. which the eye IS made to perform
its rotary movements. The lachrynal or tear
Secretlng apparatus "do eiiS' S'; ~ -
Office explained.
Nextthe beautiful and intricate construction
of the interior of the eye-ball was considered,
and the diagrams used in making its general
anatomy well understood. The retna, which
is the EXPANSION of the optic nerve, and that
mart of the eve upon which images are formed
and through which their impressions are CON
viewed to the brain, was particularly dwelt
upon. as was also the crystalline lens, which
is n small double convex lens, situated imme-
diately behind the pupil OF the eye, and
through which all the rays OF light which
reach the retina must pass. 10 the important
work of this lens, it was stated, we are largely
indebted not only for the accuracy, but ior
the wide, accommodating range OF vision.
The action of the iris, in enlarging and con-
tracing the pupil so as to accommodate the
eve to the requisite amount of light under
VARYING circumstances, was next explained.
The remaining anatomy of the eye, and the
reasons for the different colors OF the eye,
running from the intense black OF the negro,
through the brunettes and blondes, to the
pure Albino, were then considered.
The lecturer next took up the different de-
fects of vision, and explained the conditions
which produce them. Presbyopia, or old
sight, in which the crystalline lens becomes
somewhat hardened and hattened, and requir-
ing for its correction the CONFER lens. Hyper
metropia, or far sight, in which the defect is
in the fact that the diameter of the eye-ball,
from front,to back, is too short, requiring also
the convex lens. Myopia, or short sight, in
which the defect is the opposite Of the latter
condition. that is, the diameter of the eye ball
is too long, and requires for its correction the
concaUe lens. Stress was laid upon the import
ance of the early use of glasses in short sight.
After some practical suggestions in regard
to the care of eyesight, in which the subject
of artificial light was considered. The lee
turer closed by saying;
81 have now shown you the eye, and have
made such remarks upon the physiology Of
vision and the care of eyesight as seemed
proper for this lecture. We have been en-
abed, without difficulty, to follow the lines Of
light into the eye, see how an image is re
fected upon the retina, and to this exteni
understand how the visual act is performed,
There, however, in the language of the author
to whom | referred in the beginning, we
stand face to face with the incomprehensible.
Beyond the eye is the brain, whose functions
it is true, we may in many respects compre
bend, but beyond the brain is the infinite God
who made us, and whose ways are past lind
inc ont "