BUYING A HORSE 57 



duction of some irritating matter, wliich is curable by 

 simple means — and the specific ophthalmia, a spontaneous 

 affection, which ultimately culminates in cataract and 

 blindness. 



Viewed in front, the depths of the eye should be looked 

 into ; then sideways, which will assist in ascertaining 

 the clearness and absence of specks on or within its 

 surface. 



Floating in the aqueous humour (which preserves the 

 convexity of the cornea) is the iris, a muscular membrane, 

 the dilatation and contraction of which form an oval 

 aperture termed the pupil, which varies in size according 

 to the quantity of light which falls upon the eye. The iris 

 varies very little in colour in the horse, though it bears 

 some analogy to the colour of the skin. It is rarely 

 lighter than a hazel, or darker than a brown ; except in 

 milk-white, cream-coloured, or pied horses, when it is 

 white, and they are termed wall-eyed. If it is of a pale 

 variegated cinnamon colour, it is good. The pupil, or 

 aperture of the iris, is that horizontal, oblong, bluish 

 opening which admits the light to the posterior chambers 

 of the eye. It is important that the oval shape of the 

 pupil be perfect, for if any irregularity or unevenness is 

 perceived, it is a symptom that the organ has received 

 partial injury. In looking into the depths of the eye, 

 through the pupil, in a strong light, it should exhibit a 

 lively bluishness ; in a moderate light it should be perfectly 

 transparent ; if milky or turbid, that is the remanet of 

 former inflammation, which will probably recur. 



In bringing the horse out of the stable to the light, if 

 the pupil is large it is a bad sign ; by alternately shading 

 and admitting light, if it enlarges and lessens under its 

 stimulus, the eye is good. But if the retina is immovable, 

 the pupil large, and of an invariable size, whether shaded 

 or exposed to intense light — though no disorganisation 

 is apparent, the eye appearing bright, of a peculiar glossy 

 aspect, and of a greenish colour — the animal is blind from 

 the disease termed "glass eye," i.e., palsy of the optic 

 nerve. 



A decided cataract, or opacity of the crystalline lens, is 

 easily detected ; but when very small it may escape 

 observation. It appears as a cloudy or pearly white 

 substance within the pupil, towards the bottom of the eye. 



