SOUNDNESS. 19 



disease of the liver. Every part of the body is 

 liable to these two kinds of disease, and either 

 may exist separately or combined in the same 

 part. It is their union in an important part, that 

 in general makes a horse unsound. Some veter- 

 inarians therefore say, that " alterations of struc- 

 ture, attended with interruption or impairment 

 in function, constitute unsoundness." But I do 

 not adopt such a definition, because, in my opin- 

 ion, it is not sufficiently comprehensive on the 

 one hand, and is too much so on the other. Of 

 course, it excludes those diseases where altered 

 function is not combined with altered texture, 

 and hence several undoubted unsoundnesses are 

 out of its reach, such as glass eyes, partial palsy, 

 crib-biting, &c., where there is no perceptible 

 alteration in structure ; and even mange, and 

 some stages of glanders are not comprehended 

 in it, because, though there may be, and generally 

 is, alteration of structure united with impairment 

 in function, yet a slight alteration in the function 

 of the part where the disease is seated, does not 

 in every case interfere with the horse's capability 

 for work. Still these diseases constitute un- 

 soundness : the one will sooner or later destroy 

 the animal, while there is little chance of the 



