CAUSES OF UNSOUNDNESS. 75 



buyer finds, say, on the following day, that the 

 animal shies, and, on taking it to a veterinary 

 surgeon, he is informed that there is a small speck 

 on the cornea, which is apparently the cause of 

 shying. The question arises whether this was 

 present at the time of sale ; if so, there should 

 be no difficulty in compelling the vendor to re- 

 fund the purchase money. In all probabiUty the 

 vendor's argument would be that the disease had 

 sprung into existence since the time of sale, there- 

 fore the onus of proof rests with the buyer to 

 prove its existence at the time of sale. Veterinary 

 evidence would have to be relied upon. The 

 question is, how long does it take for a speck 

 (opacity) to render itself evident ? It may be at 

 once said that such may appear within a few hours 

 after an injury ; any slight scratch upon the cornea 

 is almost sure to cause it. A not uncommon cause 

 is the lash of the whip, but the best evidence, if it 

 is produced in this manner, is gleaned from the 

 shape of the mark. When the injury has only 

 been in existence for a few hours the speck is but 

 feebly marked, the milky aspect of it deepening 

 for the first few days. Again, a recent injury has 

 a tendency to spread, and not uncommonly extends 

 over the whole surface of the cornea ; but, even 



