SPHCIlic, OB PERIODIC, OPHTHALMIA. 



583 



Once, while training Gifford, one of my old pair of trained 

 horses, he ran accidentally' against the corner of a stair, striking the 

 eye so severely as to instantly destroy his power of sight ; the eye 

 was entirely closed,- and red with inflammation. In this case I sim- 

 ply kept the eye covered with a cloth kept constantly wet with 

 water in which was tincture of aconite in the proportion of about 

 40 drops to half a pint of water. There was entire recovery within 

 a week. This mild preparation has proved for. me very efficient in 

 reducing local inflammation. 



Specific, or Periodic, Ophthalmia, 



is the most severe affection to which the horse's eyi is liable, and is 



very common in this coun- 

 try. The pairts principally 

 and primarily involved are 

 the internal structures of 

 the eye, and the changes 

 which occur vary in degree 

 according to the severity 

 of the attack. 



Causes. — T he great 

 cause of this affection can 

 be traced to an hereditary 

 predisposition, always 

 ready to burst forth when 

 exposed to certain exciting 

 causes, such as injuries of 

 any kind, as before ex- 

 plained, being kept in very 

 dark and ill-ventilated sta- 

 bles, and then suddenly exposed to the glare of a hot sun ; and, like 

 simp%;pphthalmia, it may follow continued exposure to cold. 



Symptoms. — Among the first symptoms is a watery discharge 

 from one or both eyes, and on being exposed to the sunlight he ex- 

 hibits a peculiar uneasiness, with a partial closure of the affected 

 eye. As the disease advances, the eyelids become swollen, and if 

 turned upward, the conjunctiva appears reddened and injected ; the 

 eye looks smaller, and retracted into its socket ; the interior of the 

 eye reveals a peculiar muddy or turbid appearance, showing floating 

 flakes, and a yellowish or whitish deposit at the bottom of the cham- 

 ber. Fig. 902 is designed to show, on an enlarged scale, something 

 of this change. The symptoms are very like those of simple oph- 



Fig. 901. — Physiological Papilla, as Seen with the 

 Ophthalmoscope. 



