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perfect, words printed in long primer being scarcely legible. After 

 the division of the internal rectus muscle, vision not only improved, 

 but the eye became less presbyopic, and at the present time, three 

 weeks since the operation, said Dr. Hays, the glass (No. 14,) which 

 had been before adapted to the patient's left eye, now magnifies so 

 much, that it is unpleasant to read with it; and he is able to see best 

 with glass, No. 1 1 . On careful comparison, he is unable to perceive 

 any difference in the size of objects viewed with either eye through this 

 glass ; and an opera glass, adjusted to one eye, seems equally well 

 adapted for the other. These facts, Dr. Hays remarked, show, that a 

 change has taken place in the left eye, and this probably consists in an 

 elongation of its antero-posterior diameter, resulting from the operation. 



Dr. Hays also made some observations on the mode in which 

 squinting causes an impairment of the function of vision, and stated, 

 that from a great number of cases which he had examined, it ap- 

 peared to him to be a general rule, that the greater the degree of 

 strabismus, the more imperfect is the sight of the affected eye. In 

 all the cases in which he had operated, the sight had been improved. 



Dr. Dunglison stated, that he was not prepared to admit, from 

 this single observation, that the accommodating power of the eye is 

 owing to the pressure of the four recti muscles on the eye ball; 

 the division of any one of them not being likely, in his opinion, to 

 rectify the results of compression, if it existed in the case in ques- 

 tion. He was disposed to refer a great agency to the contraction 

 and dilatation of the pupil in facilitating distinct vision at different 

 distances, and he alluded to an experiment made on one of his own 

 eyes whilst a student of medicine. This consisted in applying some 

 freshly prepared extract of belladonna to the eyelids. The conse- 

 quence was, that the pupil soon became so much dilated, that the iris 

 was almost invisible. The focus of this eye was found to be at twice 

 the distance of that of the sound organ ; but in proportion as the ef- 

 fects of the belladonna passed off, and the pupil approached its na- 

 tural size, vision became more and more distinct, and the focus nearer 

 the natural. In the open air, all objects, except those near, were 

 distinctly seen, but on entering a room, every thing was obscured. 



Dr. Dunglison expressed the belief, that squinting is often owing to 

 impairment of vision in one eye, in consequence of a want of corres- 

 pondence in the sensibility of the two retina? ; the mind, therefore, 

 acquires the habit of attending to the impression made on the sound 

 eye only, and the other, being neglected, is drawn into a position to 

 interfere, as little as possible, with the better vision of its fellow. 



