124: YETERINAKY MEDICINE AND SUEGtKY. 



horse has also a peculiar power of withdrawing the eye into its orbit, 

 which adds to the difficulty of performing operations upon it. 



SIMPLE OR COMMON OPHTHALMIA. 



Synonyms. — Conjunctivitis; Inflammation of the conjunctiva. 



Definition. — An inflammation of the membrane which covers the 

 surface of the eye, and lines the eyelids. 



Etiology. — It usually has its origin in some casual injury, as a blow 

 of some sort, or some foreign substance getting into the eye. It may also 

 accompany influenza. 



Atmospheric causes are an occasional, but not very common source of 

 this disease. 



Symptoms. — Closing of the eye, accompanied by a profusion of 

 tears. General suffusion and redness about the cornea. Unless the seat 

 of injury is wholly external and therefore at once apparent, the eye 

 should be examined. Here, however, we at once meet with some dif- 

 ficulty. The animal closes his eyelids firmly. He is impatient to light. 

 As soon as we attempt to separate the lids, he withdraws his eye into the 

 socket, and the haw is thereby pushed forward, and the tears flow pro- 

 fusely. A sharp rap of the hand on the neck will sometimes cause the 

 animal to open his eye, and an opportunity to examine it will then be af- 

 forded. If this device fails, the hand should be laid steadily on the brow, 

 with the thumb resting on the margin of the upper lid; the thumb must 

 be kept quietly and firmly on the lid, until the retractor muscle ceases 

 to act violently, and then the lid should be gently pushed upward, and 

 the index finger of the other hand may at the same time draw down the 

 lower lid. 



A disturbed state of the blood-vessels and a reddened hue of the con- 

 junctival membrane will probably be noticed. Possibly, on further ex- 

 amination, we may detect a wound of the cornea, such as that inflicted 

 by a whip or by a bite from another horse. If, however, there is no sue! 

 wound, the chances are that some foreign body, such as a hayseed, has 

 lodged on the eye. The seat of such lodgment is genei'ally under tlie 

 wpper eyelid. In such cases, the removal of the foreign body is, of course, 

 the primary requisite. The upper eyelid is easily everted, with a little 

 tact, by pressing against it outer surface with the blunt end of a lead 



