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Shifting and Swinging
Shifting and Swinging
[...Shifting and Swinging
When the eye with normal vision regards a letter either at the near-
point or at the distance, the letter may appear to pulsate, or move in
various directions, from side to side, up and down, or obliquely. When
it looks from one letter to another on the Snellen test card, or,from
one side of a letter to another, not only the letters, but the whole
line of letters and the whole card, may appear to move from side to
side. This apparent movement is due to the shifting of the eye, and is
always in a direction contrary to its movement. If one looks at the
top of a letter, the letter is below the line of vision, and therefore
appears to move downward. If one looks at the bottom, the letter is
above the line of vision and appears to move upward. If one looks to
the left of the letter, it is to the right of the line of vision and
appears to move to the right. If one looks to the right, it is to the
left of the line of vision and appears to move to the left.
Persons with normal vision are rarely conscious of this illusion, and
may have difficulty in demonstrating it; but in every case that has
come under my observation they have always become able, in a longer or
shorter time, to do so. When the sight is imperfect the letters may
remain stationary, or even move in the same direction as the eye.
It is impossible for the eye to fix a point longer than a fraction of
a second. If it tries to do so, it begins to strain and the vision is
lowered. This can readily be demonstrated by trying to hold one part
of a letter for an appreciable length of time. No matter how good the
sight, it will begin to blur, or even disappear, very quickly, and
sometimes the effort to hold it will produce pain. In the case of a
few exceptional people a point may appear to be held for a
considerable length of time; the subjects themselves may think that
they are holding it; but this is only because the eye shifts
unconsciously, the movements being so rapid that objects seem to be
seen all alike simultaneously.
The shifting of the eye with normal vision is usually not conspicuous,
but by direct examination with the opthalmoscope [1]. When the optic
nerve is observed with the ophthalmoloscope, movements can be noted
that are not apparent when only the exterior of the eye is regarded.
It can always be demonstrated. If one eye is examined with this
instrument while the other is regarding a small area straight ahead,
the eye being examined, which follows the movements of the other, is
seen to move in various directions; from side to side, up and down, in
an orbit which is usually variable. If the vision is normal, these
movements are extremely rapid and unaccompanied by any appearance of
effort. The shifting of the eye with imperfect sight, on the contrary,
is slower, its excursions are wider, and the movements are jerky and
made with apparent effort.
It can also be demonstrated that the eye is capable of shifting with a
rapidity which the ophthalmoscope cannot measure. The normal eye can
read fourteen letters on the bottom line of a Snellen test card. at a
distance of ten or fifteen feet, in a dim light, so rapidly that they
seem to be seen all at once. Yet it can be demonstrated that in order
to recognize the letters under these conditions it is necessary to
make about four shifts to each letter. At the near-point, even though
one part of the letter is seen best, the rest may be seen well enough
to be recognized; but at the distance it is impossible to recognize
the letters unless one shifts from the top to the bottom and from side
to side. One must also shift from one letter to another, making about
seventy shifts in a fraction of a second.
A line of small letters on the Snellen test card may be less than a
foot long by a quarter of an inch in height; and if it requires
seventy shifts to a fraction of a second to see it apparently all at
once, it must require many thousands to see an area of the size of the
screen of a moving picture. with all its detail of people, animals,
houses, or trees, while to see sixteen such areas to a second, as is
done in viewing moving pictures, must require a rapidity of shifting
that can scarcely be realized. Yet it is admitted that the present
rate of taking and projecting moving pictures is too slow. The results
would be more satisfactory, authorities say, if the rate were raised
to twenty, twenty-two. or twenty-four a second. The human eye and mind
are not only capable of this rapidity of action, and that without
effort or strain, but it is only when the eye is able to shift thus
rapidly, that eye and mind are at rest, and the efficiency of both at
their maximum. It is true that every motion of the eye produces an
error of refraction; but when the movement is short, this is very
slight, and usually the shifts are so rapid that the error does not
last long enough to be detected by the retinoscope, its existence
being demonstrable only by reducing the rapidity of the movements to
less than four or five a second. The period during which the eye is at
rest is much longer than that during which an error of refraction is
produced. Hence, when the eye shifts normally no error of refraction
is manifest. The more rapid the unconscious shifting of the eye, the
better the vision; but if one tries to be conscious of a too rapid
shift, a strain will be produced.
Perfect sight is impossible without continual shifting, and such
shifting is a striking illustration of the mental control necessary
for normal vision. It requires perfect mental control to think of
thousands of things in a fraction of a second; and each point of
fixation has to be thought of separately, because it is impossible to
think of two things, or of two parts of one thing, perfectly at the
same time. The eye with imperfect sight tries to accomplish the
impossible by looking fixedly at one point for an appreciable length
of time; that is, by staring. When it looks at a strange letter and
does not see it, it keeps on looking at it in an effort to see it
better. Such efforts always fail, and are an important factor in the
production of imperfect sight.
One of the best methods of improving the sight, therefore, is to
imitate consciously the unconscious shifting of normal vision, and to
realize the apparent motion produced by such shifting. Whether one has
imperfect or normal sight, conscious shifting and swinging are a great
help and advantage to the eye; for not only may imperfect sight be
improved in this way, but normal sight may be improved also.
Detailed instructions for improving the sight by this method will be
given in my forthcoming book, The Cure of Imperfect Sight by Treatment
without Glasses.
[1] An instrument for viewing the interior of the eye...]
- Dr. W. H. Bates, December 1919
[...Shifting and Swinging
When the eye with normal vision regards a letter either at the near-
point or at the distance, the letter may appear to pulsate, or move in
various directions, from side to side, up and down, or obliquely. When
it looks from one letter to another on the Snellen test card, or,from
one side of a letter to another, not only the letters, but the whole
line of letters and the whole card, may appear to move from side to
side. This apparent movement is due to the shifting of the eye, and is
always in a direction contrary to its movement. If one looks at the
top of a letter, the letter is below the line of vision, and therefore
appears to move downward. If one looks at the bottom, the letter is
above the line of vision and appears to move upward. If one looks to
the left of the letter, it is to the right of the line of vision and
appears to move to the right. If one looks to the right, it is to the
left of the line of vision and appears to move to the left.
Persons with normal vision are rarely conscious of this illusion, and
may have difficulty in demonstrating it; but in every case that has
come under my observation they have always become able, in a longer or
shorter time, to do so. When the sight is imperfect the letters may
remain stationary, or even move in the same direction as the eye.
It is impossible for the eye to fix a point longer than a fraction of
a second. If it tries to do so, it begins to strain and the vision is
lowered. This can readily be demonstrated by trying to hold one part
of a letter for an appreciable length of time. No matter how good the
sight, it will begin to blur, or even disappear, very quickly, and
sometimes the effort to hold it will produce pain. In the case of a
few exceptional people a point may appear to be held for a
considerable length of time; the subjects themselves may think that
they are holding it; but this is only because the eye shifts
unconsciously, the movements being so rapid that objects seem to be
seen all alike simultaneously.
The shifting of the eye with normal vision is usually not conspicuous,
but by direct examination with the opthalmoscope [1]. When the optic
nerve is observed with the ophthalmoloscope, movements can be noted
that are not apparent when only the exterior of the eye is regarded.
It can always be demonstrated. If one eye is examined with this
instrument while the other is regarding a small area straight ahead,
the eye being examined, which follows the movements of the other, is
seen to move in various directions; from side to side, up and down, in
an orbit which is usually variable. If the vision is normal, these
movements are extremely rapid and unaccompanied by any appearance of
effort. The shifting of the eye with imperfect sight, on the contrary,
is slower, its excursions are wider, and the movements are jerky and
made with apparent effort.
It can also be demonstrated that the eye is capable of shifting with a
rapidity which the ophthalmoscope cannot measure. The normal eye can
read fourteen letters on the bottom line of a Snellen test card. at a
distance of ten or fifteen feet, in a dim light, so rapidly that they
seem to be seen all at once. Yet it can be demonstrated that in order
to recognize the letters under these conditions it is necessary to
make about four shifts to each letter. At the near-point, even though
one part of the letter is seen best, the rest may be seen well enough
to be recognized; but at the distance it is impossible to recognize
the letters unless one shifts from the top to the bottom and from side
to side. One must also shift from one letter to another, making about
seventy shifts in a fraction of a second.
A line of small letters on the Snellen test card may be less than a
foot long by a quarter of an inch in height; and if it requires
seventy shifts to a fraction of a second to see it apparently all at
once, it must require many thousands to see an area of the size of the
screen of a moving picture. with all its detail of people, animals,
houses, or trees, while to see sixteen such areas to a second, as is
done in viewing moving pictures, must require a rapidity of shifting
that can scarcely be realized. Yet it is admitted that the present
rate of taking and projecting moving pictures is too slow. The results
would be more satisfactory, authorities say, if the rate were raised
to twenty, twenty-two. or twenty-four a second. The human eye and mind
are not only capable of this rapidity of action, and that without
effort or strain, but it is only when the eye is able to shift thus
rapidly, that eye and mind are at rest, and the efficiency of both at
their maximum. It is true that every motion of the eye produces an
error of refraction; but when the movement is short, this is very
slight, and usually the shifts are so rapid that the error does not
last long enough to be detected by the retinoscope, its existence
being demonstrable only by reducing the rapidity of the movements to
less than four or five a second. The period during which the eye is at
rest is much longer than that during which an error of refraction is
produced. Hence, when the eye shifts normally no error of refraction
is manifest. The more rapid the unconscious shifting of the eye, the
better the vision; but if one tries to be conscious of a too rapid
shift, a strain will be produced.
Perfect sight is impossible without continual shifting, and such
shifting is a striking illustration of the mental control necessary
for normal vision. It requires perfect mental control to think of
thousands of things in a fraction of a second; and each point of
fixation has to be thought of separately, because it is impossible to
think of two things, or of two parts of one thing, perfectly at the
same time. The eye with imperfect sight tries to accomplish the
impossible by looking fixedly at one point for an appreciable length
of time; that is, by staring. When it looks at a strange letter and
does not see it, it keeps on looking at it in an effort to see it
better. Such efforts always fail, and are an important factor in the
production of imperfect sight.
One of the best methods of improving the sight, therefore, is to
imitate consciously the unconscious shifting of normal vision, and to
realize the apparent motion produced by such shifting. Whether one has
imperfect or normal sight, conscious shifting and swinging are a great
help and advantage to the eye; for not only may imperfect sight be
improved in this way, but normal sight may be improved also.
Detailed instructions for improving the sight by this method will be
given in my forthcoming book, The Cure of Imperfect Sight by Treatment
without Glasses.
[1] An instrument for viewing the interior of the eye...]
- Dr. W. H. Bates, December 1919
POOL TURD ALERT Re: Shifting and Swinging
"Zetsu" <absolutelyinvincible@hotmail . com > wrote
> Detailed instructions for improving the sight by this method will be
> given in my forthcoming book, The Cure of Imperfect Sight by Treatment
> without Glasses.
Yet another big, smelly floater.
Never proven, never duplicated, never generating results better than
placebo.
-MT
"Zetsu" <absolutelyinvincible@hotmail . com > wrote
> Detailed instructions for improving the sight by this method will be
> given in my forthcoming book, The Cure of Imperfect Sight by Treatment
> without Glasses.
Yet another big, smelly floater.
Never proven, never duplicated, never generating results better than
placebo.
-MT
