OF VETERINARY MEDICINE. 259 



or rubber eye can be inserted for the sake of appearance. The 

 wound should heal with little difficulty. Be sure that the instru- 

 ments are sterile before operating. 



PERIODIC OPHTHALMIA. 



Other names for this condition are Specific Ophthalmia, Re- 

 current Ophthalmia or Moonhlindness. It is an inflammatory af- 

 fection of the interior of the eye, intimately related to certain 

 soils, climates and systems, showing a strong tendency to recur 

 again and again, and usually ending in blindness from cataract 

 or other serious injury. It is peculiar to the horse. 



Semeiology. — The local symptoms are in the main those of 

 external ophthalmia, with, in many cases an increased hardness 

 of the eyeball from effusion into its cavity. The contracted pupil 

 does not contract much in darkness nor even under the action of 

 belladonna. The opacity advances from the margin of the cor- 

 nea over its whole surface. So long as it is transparent 

 there can be seen a turbid aqueous humor. This may or may 

 not contain floculi. The dingy iris is robbed of its clear black 

 aspect, the lens is cloudy and there is a greenish yellow reflec- 

 tion from the interior of the eye. From the fifth to the seventh 

 day there is a floculent precipitate which forms in the lower 

 part of the anterior chamber, exposing more clearly the iris and 

 the lens and absoption commences. The eye will clear up in 

 10 or 15 days. 



The striking characteristic of the disease, however, is its re- 

 currence again and again until blindness results. The attacks 

 may follow each other at intervals of a month, more or less, but 

 they show no relation to any particular phase of the moon as the 

 name ''moonhlindness" would lead one to think. The attacks 

 are rather determined by the weather, the health or the food, or 

 some periodicity of the system. From five to seven attacks 

 usually result in blindness in one eye and then the other runs 

 through the same course. In the intervals between the attacks 

 some symptoms remain which usually betray the condition. 

 Even after the first attacks there can usually be seen a bluish 

 ring around the margin of the cornea. The afifected eye seems 



