2. The Cause of Eyesight Problems

While this book does not propose to deal in physio­logical technicalities, which can be found in any text­book on ophthalmology, it may be helpful to summarize briefly the structure of the eye and common eyesight problems.

The eyeball is embedded in fat and fibrous tissue and lodged in bony sockets called orbits. It is held in place and rotated by means of six extrinsic muscles, attached to the posterior bony wall of the socket; at the anterior pole, they are inserted into the eye­ball.

The eyeball itself is made up of three distinct layers, or coats. The outer part, which we know as the white of the eye, but which is more properly called the sclera, is a tough, fibrous tissue, which begins where the cornea leaves off, and extends back to where it is pierced by the optic nerve. Four-fifths of the sclera is opaque; the remaining one-fifth is a translucent area directly at the front of the eye, called the cornea.

Inside the sclera is a second coat, or lining, known as the choroid, composed of blood vessels and pigment, and is essentially a nutrient organ, providing nutri­tive fluid to the retina.

Within the choroid is a third coat, an extension of the optic nerve, a sensitive membrane called the retina. This is an exceedingly thin and highly compli­cated membrane, in which are the terminations of the nerve tendrils, which are of two kinds: rods and cones. The cones are the most sensitive and are found toward the center of the retina where the keenest seeing is done.

This center, about a sixteenth of an inch in diameter, is called the macula. Here form and color and sharp definition are registered. Beyond this spot, cones and rods mingle, but toward the periphery only rods are found. These are sensitive to dim light and therefore are used for night seeing.

About a tenth of an inch to the nasal side from the center is the optic disc, the point of entrance of the optic nerve, commonly called the blind spot. You ca demonstrate this blind spot easily for yourself. Cover your left eye and look at the circle on the left with your right eye, moving the book slowly from side to side. When the right-hand circle vanishes, its image has fallen on the blind spot of the retina.

When light rays reach the surface of the retina, the radiant energy undergoes a process of chemical change, and this new form of energy is carried by the optic nerve into the visual centers of the brain.

It has long been known that the eye adjusts to various distances, a process called accommodation. In myopia, or near-sighted vision, the rays of light are thrown to a point in front of the retina:

In hypermetropia, or long-sightedness, the rays of light focus in a point behind the retina:

(Diagram of hypermetropic eye)

(Diagram of normal eye)
In normal vision, the image is focused in a point directly upon the retina itself:

HELMHOLTZ THEORY

Until recent times, however, no one knew how this accommodation was accomplished. In the nineteenth century, an Austrian ophthalmologist named Hermann Ludwig Ferdinand von Helmholtz invented the ophthalmoscope, an instrument with which it was pos­sible to look inside the eye.

As a result of his experiments, based on studies of images of a flame reflected from the front of the crystalline lens, Helmholtz evolved the theory of ac­commodation on which orthodox ophthalmology is based: that accommodation is effected by the change in shape of the lens, and this change in turn is governed by the action of the ciliary muscle. Helmholtz him­self, however, did not offer any satisfactory explana­tion as to how the ciliary muscle operated, and he confessed that his theory was merely a probability be­cause the image obtained on the lens was so variable and uncertain that, to use his own words, it was "usually so blurred that the form of the flame could not be definitely distinguished."1

According to this theory, near-sightedness, far-sight­edness, and other errors of refraction were fixed states. So it followed, if Helmholtz was correct, that the eye was unlike every other organ in the body.

That is, when accommodation was defective, there was no cure for the situation and the only treatment was to put on artificial lenses so ground as to counteract the refrac­tive error of the crystalline lens.

In The Art of Seeing, an account of his own ex­perience with the Bates method, Aldous Huxley re­marked, "If orthodox opinion is right—if the organs of vision are incapable of curing themselves, and if their defects can only be palliated by mechanical devices— then the eye must be totally different in kind from other parts of the body. Given favorable conditions, all other organs tend to free themselves from their defects."

Must we accept the illogical theory that the eyes alone are beyond cure? Nature has been found capable of effecting cures in every part of the body; in fact, the miraculous body is so constructed that it might almost be said to be designed to cure itself. The skin throws off waste products, the blood stream combats disease, the lungs can seal off an infected area; even a carcinoma, or cancerous growth, can be blocked off in a spontaneous cure.


^xHandbuch der Physiologischen Optik, Edited by Nagel, 1909-11, Vol. 1, p. 122.

But not the eyes?

Some thirty years ago, Dr. W. H. Bates, a New York ophthalmologist who examined 30,000 pairs of eyes a year at the New York Eye and Ear Infirmary and other institutions, began to make discoveries that perplexed him because they were contrary to the Helmholtz theory.

Most startling of his discoveries was the fact that there were many cases of... [Chapter Incomplete]

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