Deseret evening news. [volume] (Great Salt Lake City [Utah]) 1867-1920, 1890-04-18
DESERET EVENING NEWS.
WONDERS OF THE EYE.
CURIOUS THINGS ABOUT NATURES
PHOTOGRAPHIC CAMERA.

81 would like TO examine the in
terror Of the eye" said the oculist.
But, when he perceived n slight
shrinking en- the part Of the reporter,
who assumed for the time the role
Of patient, he smilingly added:
you need not be alarmed; il will
not hurt you n PARTICLE"
Then picking up n little disk
shaped mirror with a hole through
the center he led the patient into a
dark closet, and after lighting a
bright gas jet told him 10 Sit down
on the chair Immediately beneath.
Next he himself sat down opposite,
50 that the knees Of the two touched,
and held the small round look
ing glass in front If his
own eye, like an eyeglass,
with the mirror side outward, in
sueh "A manner that il reflected n
ray from the gas jet straight into the
PATIENTS eye through the pupil. He
could direct the ray easily enough,
inasmuch as be was looking along il
through small hole that pierced
the center OF the disk. IL you will
hold big, fiat button mold up 10
youreye and look through il at the
eye OF a person seated in front OF
you, you will get the notion Of the
way In which the Oculist operated.
suppose the button mold has quick
silvered glass on the surface turned
toward the object, and you will per-
ceive how easy il would be to throw
n ray reflected from a light above
the other persons head directly into
that other persOn's eye, and to
watch, through the hole in the but
ton mold.
WHATEVER THAT RAY REVEALED.
This was what the oculist was
doing with the mirror disk. The
ray it reflected entered the PATIENTS
eye, through the pupil, aud lighted
up the interior very much as a dark
room is lighted up 10y n bull',-sye
lantern shining through \ doorway
from outside. Just as the lantern
may be turned about this way and
that, to illuminate various parts OF
the darkened chamber beyond the
doorway, so the little looking glass
was manipulated between the fore
finger and thumb Of the physician,
as he held 10 before his own eye, in
such manner as 10 reveal 10 his
view every portion Of the inside
Of the ocular camera obscura-
for such the ey, ( ISL very much like
the camera of the photographer In
It's construction and working, and,
il has been found out quite re-
Gently that the sO-called ocular
purple'' in the eye actually produces
the pictures Of objects seen on the
nerve screen that lines the organ,
by n chemical process very much
like that employed 10y the photo
grapher to bring out the lines Of his
negatives. Possibly, some day, by
studying natures method, the sau
print artist may learn how to photo
graph colors IS the eye does. Who
knows?
The patient was very much re-
iieveI when at length he heard the
Occulist say that there was nothing
serious the matter.
81 observe n slight inflammation Of
the inner coat OF the left eye,' re- |
marked the physician, ''as well as
n mildly hyperemic condition OF
the lids, botn Of which little troubles
have undoubtedly been occasiOned
by the glasses you wear
'What is the little round mirror |
called with which you examined
any ~ es?" asked the patient while |
the 0Culist was engaged in fitting |
glasses Of various strengths into q
huge nose frame for trial.
go that little instrument, IT,
sponded the surgeon, sis due nearly |
all OF theprOgress made in ophthal-
mic scigPce since the days Of the |
ancient Egyptians, 5000 years ago.
And vet, as you see, Il is nothing but
a small, round mirror with "A hole
through il. IL is called the ophthal-
moscOpe, aud was invented by |
Helmholtz in I552. So few years
ago rs that very little was known
about the eye beyond what the old
Egyptian physicians were acquaint-
ed with. However, as 10 the Oph-
kaleidoscope, | was going TO say that
il afforded the first means ever DIS
covered for studying the interior OF
the living eye. From that point
modern ophthalmic science really
took it, rise, and there is not much
about the eye today that is not I'M
GerstOod."
NEAR sfGHTEDNESs AMONG THE
ANCIESTs.
'Were people afflicted with near
in ancient tines?"
''Oh, yes; though probably not TO
the same extent. We read, write
and study more than the ancients
did, and for this reason near-sight is
more common with us, for II is the
excessive use Of the eyes at the near
point that prOpagates the trouble. In
old times troubles with theeyes were
as atllictiOnss entby heaven,
for which there was no cure. Nero,
who liddled while Rome was burn
ing, was 50 near-sighted that al
though he had the very best seat in
the amphitheatre at the gladiator
shows, he could not see what was
going on. One day he discovered
that a certaia concave emerald in
his collection Of jewels aided his
vision materially, and from that
time he always carried the emerald
about with him, and, when he wanted
10 see anything at n distance, looked
il. He regarded the stone
rs a talisman, aud supposed that
Its prOpert es were magical"
''Is 1t true that every person needs
spectacles at some period Of life?"
Decidedly, If the person lives to
be fOrty-five years Of age. At tina:
age, or at any rate before fifty is
reached, the crystalline lens, which
is Of the consistency Of jelly in
has gradually hardened
TO the consistency Of wax, so that
the muscles which change the focus
Of the eye for various distanSes, by
altering the shape OF the lens, find
il difficult to 10 their work. You
will perceive that after looking Mt
an object across the street, TO exam
inc your finger attentively requires
n distinct effort Of the eye. You
have to exert the muscles that con-
troll the shape Of the lens in orier to
make the focus right for the near
point. II the lens has got
hard, through advancing age,
a continuous effort Of this sort,
rs in reading. becomes tire
some, and thus it is that IN, Imidil,-
aged man or woman finds the first
indication Of what is ignoraatly
termed failing sight in the blur
ring OF the letters in the book or
Now, the fact is, of
course, that the ocular organ is just
Is good As ever, save FOR the fact that
il needs a little help in the way Of