THE HORSE—THE EYE AND EAR. 151 
at objects familiar before, shying at strange vehicles, looking suspiciously at 
whatever he meets; and if he sees better in the evening or in a mild light 
than in the sunshine, 
A whitish-gray speck, or more than one, may form upon the lens of the 
eye orits enveloping sac, without any apparent previous inflammation, or 
after an injury from the removal of a piece of the front part of the eye. 
These are known as “false cataracts.” They may disappear without 
treatment, though cannabis is a valuable aid. 
TREATMENT.— When cataract is suspected, sulphur and cannabis may 
be given to ward it off. When it is confirmed, it can not be cured in the 
horse, though the use of phosphorated oil has been followed by good 
results. Mix two grains of phosphorus in one ounce of almond oil and 
put a drop into the eye once a day for several months. In man it has been 
cured by removing the lens and using glasses instead, but this does not 
wholly restore the sight, and imperfect vision from removal of the natural 
lens will cause more alarm and nervousness in the horse than an inability to 
see an object at all. Cataract that is threatened by Moon-Blindness may 
be prevented by a proper use of the expedients named for that disorder. 
OBSCURED VISION.—AMAUROSIS. 
This is a disease of the optic nerve, or the adjacent part of the brain, 
causing partial or total blindness. Its causes are excess of lignt; a blow on 
the head; injury to the eyeball; tumor pressing against the brain or optic 
nerve; apoplexy; bleeding from castration; stomach staggers; pregnancy. 
Sym ptoms.—T hese are usually obscure, and generally appear suddenly ; 
the horse is cautious in his movements; steps high; stumbles or runs 
against any object in his way; throws up his head; moves his ears back- 
ward and forward, as if to catch any sound to guide him. On careful 
examination the eye stares; sometimes has a glassy appearance; pupil 
unnaturally large, and round instead of oblong, contracting slowly, and 
not at all in later stages; the iris shrinks to a small band around the pupil. 
An unnaturally large, round pupil should create suspicion, and the horse 
should be taken to the light and the lids drawn shut for some minutes, then 
suddenly opened. If the pupil does not readily contract from the glaring 
light, the presence of the disease is at once known. ‘ 
TREATMENT.—Treatment is usually unavailing. If stomach staggers 
or other disease be the cause, that disease should be treated. Since the 
disorder is due to nervous affection, remedies which act on the nerves will 
be useful in some cases. Strychnia, nitrate of silver, or a blister on the 
cheek or behind the ears may be used with benefit. 
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