Diseases of the Eyes. 337 



only be undertaken by the surgeon. All cases should 

 have a course of tonics (oxide of iron, nux vomica, ginger) 

 as soon as the violence of the fever has abated, and should 

 be submitted to a regimen calculated to improve their 

 condition so as to ward off a new attack. Recovery from 

 a particular attack may be expected in from 6 to 10 days, 

 and this contributes to sustain the reputation of such ri- 

 diculous resorts as knocking out the wolf teeth, and sudh 

 injurious ones as cutting out the haw (hooks). 



OATAEACT. 



This is the most constant result of internal ophthalmia, 

 though it may occur from other causes, such as diabetes or 

 uraemia. The condition is opacity of the lens, and may 

 be recognized as a white speck, or a white fleecy cloud 

 filling, in the worst cases, the whole of a widely dilated 

 pupil. It is best seen with the animal looking out of the 

 stable door, and with a dark background. A still more 

 satisfactory examination can be made with a hghted taper 

 in a dark room. Three images of the taper are reflected, 

 (1) from the surface of the eye (cornea), (2) from the an- 

 terior surface of the lens, and (3) from the posterior sur- 

 face of the lens. The two anterior are upright, the pos- 

 terior is inverted. If either of the two posterior images 

 is changed into a diffuse white haze ia passing over any 

 part of the pupil it implies an exudation into that part of 

 the lens — a cataract. Haziness of the large anterior im- 

 age is only caused by_opacity of the cornea. 



Treatment. Newly formed cataracts will sometimes 

 clt ar up, by absorption, under such treatment as is adopted 

 for inflammation, but the rule is that an opacity of the 

 lens once found, is permanent. In cattle and sheep the 

 lens may be extracted or depressed as in man, but in the 

 horse such an operation would be worse than useless, as 

 without spectacles he coidd never see things in their right 

 form or position, and would become an incorrigible shyer, 

 Better leave him bUnd. Cases not due to recurring oph- 

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