WITH PHYSIOLOGICAL OBSERVATIONS. 61 



rection outwards, the pupil, in passing the centre of the orbit, contracted a little, and, 

 when approaching the outer canthus, expanded again to the size it held when the 

 eye was in its usual inverted position. On looking from the temporal side into the 

 pupil, a large portion of the opake capsule was observed in the posterior chamber. 

 The interior of the eye-ball presented a brownish-black appearance. The patient 

 had not the slightest perception of light with this eye ; it was perfectly amaurotic. 

 The left eye presented in the conjunctiva, especially at the inner canthus, a number 

 of varicose vessels, and in the scleiotica a fine vascularity around the outer half of 

 the cornea ; this latter membrane was regularly convex, clear, and perfectly pellucid 

 The fibres of the iris were rather irregular ; its brown colour not equally diffused. 

 The pupil, which was uncommonly large, was not round, but drawn angularly down- 

 wards and inwards, neither altering 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 was observed undestroyed, rendered opake 

 in its whole extent, hypertrophied in several places, and of a colour and lustre 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 perpendi- 

 cular cleft of about one line and a quarter in length. This cleft was situated so far 

 from the centre of the pupil that it was entirely covered by the iris, and the inferior 

 border being united to the uvea, it was kept a little open, so that the aqueous humour 

 had free entrance into the cavity of the capsule. Except at the spot where the union 

 of the capsule with the uvea took place (the cause of the angular form of the pupil), 

 these two membranes were not in contact w^ith each other. The patient only com- 

 plained of an occasional sensation of pressure in the interior of the eye ; otherwise 

 the organ was free from pain. With this eye he had a perception of light, and was 

 even capable of perceiving colours of an intense and decided tone. He believed him- 

 self 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 towards the pupil. But this I am con- 

 vinced was a mere delusion ; for, from the state of the interior of the eye, as just de- 

 scribed, it is evident that all rays of light falling in the direction of the optic axis in 

 the pupil must be intercepted, and reflected by the opake capsule. By these rays, 

 therefore, a perception of light indeed might be conveyed, but certainly no percep- 

 tion 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 

 must fall at a place situated about midway between the ciliar ligament and tlio 

 centre of the posterior hemisphere, where, from the laws of optics, they could produce 

 but a very imperfect image ; and, owing to this imperfection of the image, it was im- 



