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eye, and generally involves both visual organs at the same time. The pupil 
does not react to light, that is, it does not contract and dilate, when light is 
admitted into, and shut out from, the eye. The lids are wide open; and, 
when both eyes are affected, the animal is quite blind. This affection, 
when dependent upon disease of the nerve itself, is incurable; but, when it 
depends upon other causes, the eye may possibly be restored again to its 
normal condition. Therapeutic measures will usually avail nothing for the 
cure of this affection. Among the actual causes of this disease, are the 
growth of tumours in the brain, and blows on the eye. 
By cataract, we understand an opaque condition of the lens of the eye, 
or of its capsule, which obscures the vision of the animal. It necessarily 
constitutes unsoundness, for, although it may be very small, it is nevertheless 
very liable to increase, and eventually results in blindness of the affected eye. 
It must be carefully distinguished from specks on the cornea, which are, as 
a rule, the result of previous inflammation. 
FINIS. 
