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not alter in dimension with the movements of the eye nor from the stimulus of light. On examining the eye by looking straight into it through the pupil, the anterior wall of the capsule appeared opaque in its whole extent, and of a color and luster like mother-of-pearl. On looking from the temporal side in an oblique direction into the pupil, there was visible in the anterior wall of the capsule a very small perpendicular cleft of about one line and a quarter in length. "This cleft was situated so far from the center of the pupil that it was entirely covered by the iris. With this eye the patient had a perception of light, and was even capable of perceiving colors of an intense and decided tone. He believed himself, moreover, able to perceive about one third of a square inch of any bright object, if held at the distance of half an inch or an inch from the eye, and obliquely in such a direction as to reflect the light strongly toward the pupil. But this, I am convinced, was a mere delusion, for all rays of light falling in the direction of the optic axis must have been intercepted and reflected by the opaque capsule. By these rays, therefore, a perception of light, indeed, might be conveyed, but certainly no perception of objects. On the other hand, it seems probable that the lateral cleft in the capsule permitted rays of light to pass into the interior of the eye. But as this small aperture was situated entirely behind the iris, those rays only would have permeated which came in a very oblique direction from the temporal side. Admitting, then, these rays of light to pass through the cleft, still on account of their obliquity they could produce but a very imperfect image, because they impinged upon an unfavorable portion of the retina. Moreover, I satisfied myself by experiments, that the patient could not in the least discern objects by sight. My experiments led me to the conclusion that his belief that he really saw objects resulted solely from his imagination combined with his power of reasoning. In feeling an object and bringing it in contact with the eyelids and the cheek, an idea of the object was produced, which was judged of and corrected according to the experience he had gained by constant practice. "The patient's sense of touch had attained an extraordinary
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