THE EYE 131 



and proves how necessary they are as a protection to 

 the eye. 



The eye of a horse is more prominent and propor- 

 tionately very much larger than our own, so much so 

 that were provision not forthcoming to counterbalance 

 this peculiarity, the very greatest annoyance would 

 occur to the animal from the lodgment of dust, sand, 

 insects, etc. This provision is, however, afforded by 

 the lachrymal gland — a large, irregular gland, which 

 secretes an aqueous fluid, v^hich issues from it and is 

 allowed exit by the mere process of winking, and thus 

 washes away all foreign objects. This flow of relief is 

 termed ' tears,' and serves to quell any inflammation. 

 I have often seen horses suffer excruciating pain from 

 a blow in the eye, so that when water is observed to 

 be issuing from the eye and running down the cheek, 

 the eye should be examined for the presence of some 

 foreign object, and if this is not discoverable it ma}'- be 

 concluded that the eye has received a blow. 



There is a very beautiful triangular-shaped mem- 

 brane which is concealed in the corner of the eye of 

 a horse, and which the latter is able at will to slide 

 like a kind of shutter across the eye, in order to re- 

 move any substance, such as dust, flies, etc., which 

 may have lodged on the eyeball, and it also serves as 

 a protection to the eye in event of any danger threaten- 

 ing that organ. The eyeball being withdrawn some- 

 what back, permits this membrane to pass over it ; on 

 the eyeball being again allowed to resume its usual 

 position, the membrane slides back into its place. 



At times this membrane may become thickened by 

 reason of inflammation, and cases have not been 

 infrequent in which the cruelty of ignorance has caused 



