IN SEARCH OF A HORSE. 139 



three times, and covering it, while closed, with the 

 hand : on rapidly withdrawing the hand, you will 

 notice a contraction of the pupil, as soon as it is ex- 

 posed to the glare of sudden light. It will material- 

 ly assist the judgment to notice whether the oval 

 outline of the pupil is perfect ; if any irregularity or 

 unevenness is perceived, (except as to the upper line, 

 for the reason already mentioned) — this, though no 

 proof that the optic nerve is diseased, is a certain 

 mark that the organ has received partial injury ; and 

 it is immaterial to a purchaser from what cause it 

 has proceeded, if he is satisfied that injury has been 

 received. 



A decided cataract is readily detected, when the 

 nature of the complaint is explained : it is an opacity 

 of the crystalline lens. If the pupil appears to be 

 occupied by any cloudy and whitish substance, I will 

 not say, speaking scientifically, that it is a certain 

 evidence of cataract, but it is presumably to be as- 

 cribed to that cause, and at all events it is conclusive 

 as to there being a defect of sight. If the pupil has 

 a circular, instead of a flat, oval shape, already des- 

 cribed, this too, may be considered as an indication 

 of cataract. 



