136 DK. LEGEAK'S STOCK BOOK. 



CHAPTER X. 

 DISEASES OF THE EYE. 



We can scarcely overestimate the value of sound eyes in the 

 horse, and hence all diseases and injuries of the eye, if they prove 

 permanent, will greatly depreciate the usefulness and value of 

 the horse. A blind horse is always dangerous in the saddle or in 

 single harness. Again, a horse with partial sight or impaired 

 vision that sees things imperfectly, or imagines he sees things 

 that are not present, is still more dangerous than a totally blind 

 horse. 



SIMPLE, OE EXTERNAL OPTHALMIA. 



This is a disease nearly always caused by an injury and is an 

 inflammation of the lining membrane (conjunctiva) of the eye, 

 and if neglected will in many instances cause great trouble. 



Causes. It may be caused by blows with whips, clubs, or twigs, 

 the presence of foreign bodies like hay-seeds, grassburrs, chaff, 

 dust, lime, sand, etc. Foul air from badly kept stables or keep- 

 ing a horse in a dark, damp stable and sudden exposure to the 

 bright sunlight may cause the trouble. 



Symptoms. The eye is partially or completely closed, water- 

 ing of the eye, swollen lids, redness of the mucus membrane, 

 etc. After a short time the whole cornea may turn a bluish or 

 \vhitish color, and a thick, yellow deposit may take place in the 

 lower part of the eye. If due to a direct injury to the cornea a 

 \vhite spot can be plainly seen on the cornea. This bluish or 



