14 EXAMINATION OF HORSES 



wheat husk purposely introduced under the upper 

 eyelid of a horse suffering from cataract, for reasons 

 too obvious to mention. 



The cornea, of all other structures of the eye, most 

 frequently shows signs of previous disease ; and when 

 we allow ample room for enlargement of the pupil in 

 comparative darkness, the cornea in front of the pupil 

 so dilated claims our special attention ; for any opa- 

 cities, from whatever cause, are unsoundness so long 

 as they may last, and it is for us to determine whether 

 they are temporary or permanent. The degree of 

 opacity within this area must be entirely set aside, as 

 there is no opacity which can be seen by us that 

 will not materially interfere with the rays of light, and 

 therefore with vision. When we come to remember 

 how frequently the whip is abused, we must be care- 

 ful in noticing the cornea of the right eye more espe- 

 cially; and since we do not find the pupil fully 

 dilated, we may safely allow that the eye is prac- 

 tically sound if the opacity is so near the margin of 

 the cornea as the sixth of an inch, and is of long 

 standing — that is, that it is not progressive. Should 

 any cicatrix from wound or ulcer, no matter on what 

 part of the cornea it occur, alter its convexity, then 

 it is unsoundness; indeed, you should always look at 

 the convexity of the cornea; for if conical or too flat, 

 we have not the means of rectifying the ingoing rays 

 by lenses (spectacles) ; therefore such eyes cannot be 

 considered sound. 



