ON THE HORSE’S EYE. 
21 
allowed to run its course. The symptoms in this condition 
are but an aggregation of the former more pronounced. 
Lachrymation and intolerance to light increases, the lids 
become very swollen, so that the upper hangs down in a thick 
heavy fold. They are red, glistening, and oedematous, and 
if pressed upon are very tender. The conjunctiva becomes 
vascular and swollen, and patches of effused blood are 
noticed covering more or less of its surface. They often 
bleed freely on the slightest touch, as their epithelial cover¬ 
ing is very thin and easily shed. As the disease advances 
the discharge increases in quantity, becomes more opaque, 
thick and creamy; and on account of its admixture with 
blood, frequently assumes a reddish-yellow tint. The chief 
danger in purulent ophthalmia is the implication of the cor¬ 
nea. Any cloudiness of the latter must necessarily be looked 
upon as an untoward symptom. Sometimes there is a seri¬ 
ous infiltration into the cornea, which may remain confined 
to the periphery. If this opacity is considerable and extends 
over the center of the cornea, the sight may be greatly im- 
pared. Generally the infiltration changes into an ulcer, 
which may, in favorable cases, remain superficial, and as such 
may leave very little or no opacity of the cornea. The 
greatest attention must be paid to local treatment. The eyes 
should be frequently cleansed of the discharge. A moderate 
solution of nitrate of silver or sulphate of zinc should be 
applied. Ice compressed may also be applied to the eyelids, 
as it will often cut short the attack. If the temperature of 
the lids is but moderately increased, it is only necessary to 
employ cold compresses for an hour or two after the appli¬ 
cation of caustics, for we thus assist the astringent action of 
the caustic upon the blood vessels, and also moderate the 
reaction produced by it. The after-treatment consists of a 
saturated solution of borax, alternated with sulphate of copper. 
Periodic ophthalmia is the disease of the eyes in the lower 
animals that has baffled the skill of such men as Williams, Dick, 
Percivall and Coleman. And they lay it down in their works 
as one in which they do not feel justified in suggesting any 
line of treatment that will prove successful. They all agree 
