The Iowa plain dealer. [volume] (New Oregon, Howard County, Iowa) 1867-1895, 1884-10-30
DO THE EYES GET TIREDi
Some Popular Errors CONCERNING FatlG
uf tho Ontlc Organs.

Some Popular Errors Concerning Fatigue
of tho Optic Organs.
Persons speak Of their eyes being
fatigued, meaning thereby that the
seeing portion Of the brain IL fatigued,
but in that they are mistaken. 30
men say thnt their brains are tired.
Brains seldom become tired. The
rctinn OF the eve. which is part
Of the brains, and an offshoot from it,
hardly ever is tired. The fatigue is in
the inner and outer muscles attached TO
the eye and in the muscles Of accom-
mediation. The eyeball, resting in a
bed Of fat has attached to it six mus
cles for turning IL in any desired dircc-
tion, and the MUSCLE attached 10 the
side nearest The nose and one ut the
outer angle OF the eye should, In every
normal eye, bc balanced. They are used
IN converGing the eye on The object to
be viewed, and tho inner muscles are
used the more when the object is
near. The muscle OF accommodation
il the ono whica surrounds the lens Of
the eye. When il is wanted to gaze at
an object near at hand this muscle
rclaxes and allows the lens to thicken,
increasing its retractiye power at the
same time that the muscles OF the inner
or nasal side Of the eye contract and
direct the eye to the point gazed at. II
il IN these muscles that tho fatigue is
felt, aud one finds relief in closing the
eyes or in gazing at objects ut . DIS.
tance. The chief source of fatigue is
in the lack Of balance in tho two sets of
inner and outer muscles OF accom-
mediation.
II alay be set down that there is some
thing wrong when the eye becomes
fatigaed. The defective eye, as IL
gives out sooner. is really safe from
severe strains. The usual indication oi
strain is the rcdness Of the rim Of the
eyelid, betokening congestcd state oi
the inner surface, accompanied with
some pain. When il il shown that the
eye is not equal to the work required oi
it, the proper remedy is not rest, for
that is fatal to the strength, but the
use Of glasses of sufficient power tc
render unnecessary 30 much effort in
accommodating the eve to its vision. II
Is not good sense to waste time in rest
ing the eyes, and the practice docs moi
strengthen them.
Ewes begin to age nt about the tenth
or twelfth year of life, when they have
reached their full development. Al
the age OF forty-tive or fifty years the
lenses cease 10 shickcn, when tho pres.
sure is removed and then presbaGpia,
or old sight. begins. When a child il
compelled to use or requires the use ol
glasses there is little reason to hope
that il will outgrow their use, but the
person will use these glasses A. basis,
adding other glasses as he reaches the
age when old sight begins, or using the
thicker glasses. A case has been known
wherc child had ontggown the use oi
glasses, but in the meantime he had
grown from small md pnny child to Z
large and well-developed man.
Second sight, or the apparent recov'
cry Of strength of vision, which il
sometimes seen in persons Of advanced
age, is change. an clongation in the
shapc Of the eyeball, by which the per
son became nearsighted, accompanied
by change in tho lenses caused by tn,
appearance OF cataract. Lecture bl
DR.. W. W. Scc'y.