288 DISEASES OF THE HOBSE, 



eyelids." In the absence of anything better, cold water may serve 

 every purpose. Above all, adhesive and oily agents (molasses, sugar, 

 fats) are to be avoided, as only adding to the irritation. By way of 

 suggesting agents that may be used with good effect, salt and sulphate 

 of soda may be named, in solutions double the strength of sulphate of 

 zinc, or 7 grains of nitrate of silver may be added to a quart of dis- 

 tilled water, and will be found especially applicable in gi*anular con- 

 junctivitis, diphtheria, or commencing ulceration. A cantharides 

 blister (1 part of Spanish fly to -i parts lard) may be rubbed on the 

 side of the face 3 inches below the eye, and washed off next morning 

 M^ith soapsuds and oiled daily till the scabs are dropped. 



WHITE SPECKS AND CLOUDINESS OF THE CORNEA. 



As a result of external ophthalmia, opaque specks, clouds, or hazi- 

 ness are too often left on the cornea and require for their removal 

 that they be daily touched with a soft feather dipped in a solution of 

 3 gi'ains nitrate of silver in 1 ounce distilled water. This should be 

 applied until all inflammation has subsided, and until its contact is 

 comparatively painless. It is rarely successful with an old, thick scar 

 following an ulcer, nor with an opacity having red blood vessels 

 running across it. 



ULCERS OF THE CORNEA. 



These may be treated with nitrate of silver lotion of twice the 

 strength used for opacities. Powdered gentian, one-half ounce, and 

 sulphate of iron, one-fourth ounce, daily, may improve the general 

 health and increase the reparatory power. 



INTERNAL OPHTHALMIA (IRITIS, CHOROIDITIS, AND RETINITIS). 



Although inflammations of the iris, choroid, and retina — the inner, 

 vascular, and nervous coats of the eye — occur to a certain extent inde- 

 pendently of ea?h other, yet one usually supervenes upon the other, 

 and, as the symptoms are thus made to coincide, it will be best for 

 our present purposes to treat the three as one disease. 



Causes. — The causes of internal ophthalmia are largely those of the 

 external form only, acting with greater intensity or on a more suscep- 

 tible eye. Severe blows, bruises, punctures, etc., of the eye, the 

 penetration of foreign bodies into the eye (thorns, splinters of iron, 

 etc.), sudden transition from a dark stall to bright sunshine, to the 

 glare of snow or water, constant glare from a sunny window, abuse 

 of the overdraw checkrein, vivid lightning flashes, drafts of cold, 

 damp air ; above all. when the animal is perspiring, exposure in cold 

 rain or snowstorms, swimming cold rivers; also certain general 

 diseases like rheumatism, arthritis, influenza, and disorders of the 



