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The symptoms are watering of the eye, swollen lids, redness of the 

 mucous membrane exposed by the separation of the lids — it may be a 

 mere pink blush with more or less branching redness, or it may be a 

 deep, dark red, as from effusion of blood — and a bluish opacity of the 

 cornea which is normally clear and translucent. But except) when re- 

 sulting from wounds and actual extravasation of blood, the redness is 

 seen to be superficial, and if the opacity is confined to the edges, and 

 does not involve the entire cornea the aqueous humor behind is seen to be 

 still clear and limpid. The fever is always less severe than in internal 

 ophthalmia, and only runs high in the worst cases. The eyelids may 

 be kept closed, the eye-ball retracted, and the haw protruded over one- 

 third or one-half of the ball, but this is due to the pain only and not to 

 any excessive sensibility to light, as shown by the comparatively widely 

 dilated pupil. In internal ophthalmia, on the contrary, the narrow 

 contracted pupil is the measure of the pain caused by the falling of 

 light on the inflamed and sensitive optic nerve (retina) and choroid. 



If the affection has resulted from a wound of the cornea, not only is 

 that the point of greatest opacity, forming a white speck or fleecy cloud, 

 but too often blood-vessels begin to extend from the adjacent vascular 

 covering of the eye (sclerotic) to the white spot, and that portion of 

 the cornea is rendered permanently opaque. Again, if the wound has 

 been severe, though still short of cutting into the anterior layers of the 

 cornea, the injury may lead to ulceration which may penetrate more or 

 less deeply and leave a breach in the tissue which, if filled up at all, is 

 repaired by opaque fibrous tissue in place of the transparent cellular 

 structure. Pus may form, and the cornea assumes a yellowish tinge 

 and bursts, giving rise to a deep sore which is liable to extend as an 

 ulcer, and may be in its turn followed by bulging of the cornea at that 

 point (staphyloma). This inflammation of the conjunctiva may be 

 simply catarrhal, with profuse mucopurulent discharge; it may be 

 granular, the surface being covered with minute reddish elevations, or 

 it may become the seat of a false membrane (diphtheria). 



In treating external ophthalmia the first object is the removal of the 

 cause. Remove any dust, chaff, thorn, or other foreign body from the 

 conjunctiva, purify the stable from all sources of ammouiacal or other 

 irritant gas; keep the horse from dusty roads, and above all from the 

 proximity of a leading wagon and its attendant cloud of dust ; remove 

 from pasture and feed from a rack which is neither so high as to drop 

 seeds, etc., into the eyes nor so low as to favor the accumulation of 

 blood in the head ; avoid equally excess of light from a sunny window 

 in front of the stall and excess of darkness from the absence of win- 

 dows ; i^reserve from cold draughts and rains and wet bedding, and ap- 

 ply curative measures for inflammation of the adjacent mucous mem- 

 branes or skin. If the irritant has been of a caustic nature remove 

 any remnant of it by jjersistent bathing with tepid vrater and a soft 

 sponge, or with water mixed with white of egg, or a glass filled with 



