410 GHAPTEU 57. 



should be admitted : the body should be kept warm by clothing ; a linen 

 shade kept constantly wet should be applied over the eyes by day, as the 

 organ is intolerant of light. 



When the attack is an isolated one, a dihgent search should be made 

 for the causes which may have induced it ; and any such causes, if dis- 

 covered, should if possible be removed or reversed. Thus, if the horse is 

 fat and in high condition, depletives may be beneficial; -whilst on the 

 other hand, if the animal is low, good feeding and tonics will be appro- 

 priate. If the horse has been standing in a dark stable, and the eyes on 

 that account j^erhaps have become weak, it is probable that the tone of 

 the part will be benefited by the stimulus of a little more light during 

 the periods of intermission of the attacks. If, on the other hand, the 

 eyes have been affected by excess of light, relief may be given by de- 

 creasing it. 



Such measures may not perhaps have very much effect, but still they 

 ought not to be neglected. Their benefit consists not so much in reduc- 

 ing any existing attack — -for that will abate under almost any or indeed 

 without any treatment ; but in the chance they afford, that by careful 

 avoidance of all predisposing causes, added to careful attention to the 

 general health and to good stable management in every detail, they may 

 w^ard oft" the recurrence, or at least mitigate the violence of future attacks. 

 By such care, with time, age, and increasing strength, there is some little 

 reason to hope that kind nature may enable the system to wear out the 

 disease and resist its occurrence. In most cases, however. Specific Oph- 

 thalmia in spite of all treatment runs its course, sometimes unobtrusively 

 and with scarcely noticeable force, and at other times with acute 

 symptoms. 



Bleeding, however, as a general depletive, may be useful in some cases, 

 where the pulse and other symptoms indicate the need of such a remedy. 

 Setons under the eye, or preferably, rowels in the space between the jaws, 

 or blisters to the face and between the jaws, have been frequently tried, 

 but generally without producing any beneficial result. 



847. Cataracts. 



Cataracts are divided into true and spurious. The scat of true cataract 

 is in the crystalline lens, in its capside, or in both, or even between the 

 lens and its capsule. Any opacity in the lens must seriously interfere 

 with the vision. So likewise, though in a lesser degree, any opacity in 

 the capsule or between the capsule and the lens will affect the power of 

 sight. There are three classes of true cataract, distinguished as to name 

 by the position they occupy, namely Lenticular, Capsular, and Capsulo- 

 lenticular or Interstitial. 



The colour of a cataract depends on various circumstances, and esj>c- 

 cially on the length of time that has elapsed since its formation. In the 

 very early stage the lens may show only a slight nebulosity ; later there 

 may be seen in it streaky lines radiating to a centre, and at last cataract 

 may be fully developed as a circumscribed white spot gradually increasing 

 in size. 



