Essays on the anatomy of the eye / by Arthur Jacob.

  • Jacob, Arthur, 1790-1874.
Date:
1824
Catalogue details

Licence: Public Domain Mark

Credit: Essays on the anatomy of the eye / by Arthur Jacob. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    accidental, and the consequence of changes occur- ring after death. It is here necessary to call to mind what those changes are with respect to the retina. If the eye had become flaccid previous to dissection, the retina, on being exposed, presents an irregular surface, arising from a number of folds diverging from the optic nerve as from a centre, and evidently produced by the loss of support, from the partial evaporation of the fluid of the vitreous humour. These folds, however, never observe any regular form, or preserve precise situations, and may be obliterated by changing the position of the eye in the water. They disappear altogether after the part has remained some time in water, in con- sequence of the vitreous humour becoming again distended, from imbibing the fluid in which it is immersed. It, however, requires no very great care or experience to distinguish between those ac- cidental folds and the peculiar one in question. If the examination be made from without, removing- the sclerotic and choroid behind, the retina appears to be forced or drawn at this point into the vitre- ous humour, to the depth of about a twelfth of an inch, the entire fold being something more than an eighth in length. At first there is little or no ap- pearance of a hole, but after the eye has remained for some time in the water, the fold begins to give way, and a small slit makes its appearance, which gradually widens, and assumes the appearance of a round hole. This hole is large in proportion to the degree to which the fold has yielded ; and when