Lesson 13

The eye is about one inch in size. It is about one inch from the cornea to the retina. To focus one inch takes about 40.00 optical diopters of curvature. This is divided between the cornea and the eye lens. The cornea has about 30 diopters of plus curvature. The eye lens, when it is relaxed or flattened, has about ten diopters of plus curvature.

The curvature of the eye lens is proven by the following facts: When the eye lens is extracted in operations for cataract, it takes about a plus 10 diopter spherical lens, in glasses, to replace it for clear distant vision. It takes about 3.00d. more for reading at 13 inches. It taks a lens of more than 100.00d. for hyper-sighted eyes. It takes a weaker lens for near-sighted eyes. A cataract lens is, ordinarily, a plus 10.00d. spherical lens.

Should the eyes grow bigger, if the growth is natural and symmetrical, it would make no difference for the focus. A larger sphere or a larger eye has less curvature. It would focus on the retina just the same as the one inch eye. Should the eye be smaller it would also make no difference. A smaller sphere or a smaller eye has more curvature to focus nearer.

It is claimed by many authorities that the far-sighted or hyper-sighted eyes are smaller eyes and near-sighted eyes are those whih grow bigger. This is a fanciful assumption. The midgets are not all hyper-sighted and the giants are not all nearsighted. The small birds cannot see farther than the eagle -- the eagle, surely, is not near-sighted.

The natural size and the natural growth of the eyes should have little to do with being hyper-sighted and becoming near-sighted. It is the unnatural use and the subsequent unnatural growth which can, and does, make our eyes poor-sighted, near-sighted and astigmatic.


The optical curvature of our eyes and of lenses are relative curvatures; it is similar to relative humidity.

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