94 OPHTHALMOLOGY FOR VETERINARIANS 



followed by the yellow oxid of mercury ointment to 

 promote healing. One of the best mild antiseptic washes 

 is the saturated solution of boric acid with a little 

 astringent added. Zinc sulphate is usually employed 

 for this purpose in the strength of | to i grain to the 

 ounce. 



If the ulcer is a foul one, that is, filled with purulent 

 matter, the object in treatment is to kill the bacteria 

 causing it, and at the same time to prevent its advance- 

 ment. Cure ting the ulcer to the healthy tissue was 

 formerly employed, and in some cases is a valuable pro- 

 cedure if done by experienced hands ; but much care must 

 be used, or more damage than good will be done by the 

 use of the curet. One of the best cleansing agents is one 

 of the new silver salts, either argyrol or protargol, from 

 lo to 50 per cent, solution. It is well to use the stronger 

 solution at first, gradually reducing the strength as one 

 gets results. This should be dropped into the eye, 

 and soon washed away with the purulent matter which 

 the silver salt has coagulated. This operation can be 

 repeated every one, two, or three hours, according to the 

 severity of the case; between times wash the eye freely 

 and frequently with a saturated solution of boric acid. 



If the ulcer does not respond to this treatment, but 

 rather increases in size and depth, touch it slightly with 

 the strong tincture of iodin. As this is exceedingly pain- 

 ful, it should be preceded by the application of a 5 to 10 

 per cent, solution of cocain dropped on the cornea. 



