St. Paul daily globe. [volume] (Saint Paul, Minn.) 1884-1896, 1895-01-31
THE INNER EYE.
Oculists Have Not Yet Succeed
Z ed in the Effort to Photograph

Oculists Have Not Yet Succeed
z cd in the Effort to Photograph
1t. s...
New York Sun.
Some of the oculists interested in the
effort to photograph the interior of the
human eye are looking to chemistry for
the next relief from the adverse condi-
tioa with which they are confronted.
The efforts to photograph in colors are
likely, if successful, to aid materially
in the work of securing picture of the
interior of the eye by producing pho
tographic plate sensitive to the red
rays of light. Apparently the latest
paper written on the general subject
of phctographing the human eye is
one by DR.. Lucien Howe, of Buffalo,
N. Y. It is published in the record
of the fourteenth session of the Opn-
archaeological Society of the United
Kingdom, which ended in July.
DR.. Howe calls attention to the ease
with which, theoretically, such a pho
tograph can be made, which has led
to the making of many attempts to
SECURE one. But the attempts, from the
earliest to the latest, have been mainly
useful in showing the difficulties in the
way of their accomplishment. DR..
Howe mentions one by DR.. Rosbrugh,
of Toronto, who secured a picture of
the interior of a cats eye, but it
merely shows an indefinite ontline of
some objects at the base of the globe
of the eye. Even the outline of optic
nerves can not be distinguished. Some
lines appear radiating from the center,
and give to the picture so blurred an
no Tlr IL
would hardly be recognized as pho
tograph of the interior of the eye
unless one knew beforehand what was
to be looked at. These lines he as
cribeS to the corneal reflex.
Although for fifteen years little of
note was done along this line, many
attempts have been made in the last
five years. In 1890 DR.. A. Eugene Flick,
of Zurich, got picture of the fundus
or base of the eye of an albino rabbit,
but, although two or three vessels
can be seen, there is no distinct out
line of the optic nerve. In 1891 DR.. Os-
valid Gerloff, to obviate the corneal
reflex, covered that part of the eye,
and, although he did away with the re-
/ f1eX, the vessels were hardly more ap-
parent than in DR.. Fick's picture. DR..
Gerloff'S picture was of human eye
blind from atrophy.
By the use of orthochromatic or iso-
chromatic plates, such as are made for
the efforts to take photographs in
colors and to be sensitive to red light
rays, DR.. Howe took several pictures
Of an artificial eye, and the outlines of
thet vessels were as distinct as when
seen in normal eye with the ophthal-
moscope. But in photograph he
took also with an isochromatic plate,
of a normal human eye with the pupil
widely dilated, only the outline of the
-disk could be plainly seen, and three
!, OF four vessels could be traced to
Considerable distance. This photo
graph, although imperfect, is called the
best one SO far produced.
. The examiners eye at the ophtha1-
moScope being merely a camera, it is
{ theoretically one of the easiest things
|, Imaginable to replace it with a photo
graphic camera and let the pictures so
|, clearly produced on the examiners
retina be impressed on the photo
graphic plate. But, in experiment. the
result, seemingly natural and inevi-
table, does not come about. The light
reflected from the fundus oculi, or base
of the globe of the eye, is red, and so
has little or no effect on the film of the
Photographic plate, just as red light
used in the photographers dark room
does not effect the plates he is de-
yeloping, which would be ruined by
white light. So DR.. Howe thinks re-
lief must come from the chemist. The
manufacturers have been making
plates somewhat sensitive to red rays,
and DR.. Howe looks to them for the
next advance in the experiments of
photographing the eyes interior. He
suggests, too. that it is necessary that
the plates be exceedingly rapid. AS
drawings to show conditions of the
eye are unreliable, photographs are
much to be desired, and DR.. Howe's
paper was intended in the way of sug-
gestion to other experimenters.