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condition wliicli undermines the general liealtli. The presence of 

 worms in the intestines, overwork, and debilitating diseases and causes 

 of every kind weaken the vitalitj^ and lay the sj'stem more open to 

 attack. Thierry long ago showed that the imxjrovement of close, low, 

 dark, damj) stables, where the disease had previously prevailed, prac- 

 tically banished this affection. Whatever contributes to strength and 

 vigor is x)rotecti^e — whatever contributes to weakness and poor health 

 is provocative of the disease in the predisposed subject. 



The symptoms vary according to the severity of the attack. In some 

 cases there is marked fever, and in some slighter cases this may be 

 almost altogether wanting, but there is alwaj's a lack of vigor and 

 energy, bespeaking general disorder. The local symptoms are in the 

 main those of internal ophthalmia, with, in manj' cases, an increased 

 hardness of the eye-ball from effusion into its cavity. The contracted 

 pupil does not expand much in darkness, nor even under the action 

 of belladonna. Opacity advances from the margin, over a j)art or 

 whole of the cornea, but so long as it is trausx)arent there may be seen 

 the turbid, aqueous humor with or without flocculi, the dingy^ iris 

 robbed of its clear black aspect, the slightly clouded lens and a green- 

 ish yellow reflection from the dei)tli of the eye. From the fifth to the 

 seventh day the flocculi i)recipitates in the lower part of the chamber, 

 exposing more clearly the iris and lens, and absorption commences so 

 that the eye may be cleared u^) in ten or fifteen days. 



The characteristic of the disease is, however, its recurrence again 

 and again in the same eye until blindness results. The attacks may 

 follow each other at intervals of a month, more or less, but they show 

 no relation to any particular xjhase of the moon as might be inferred 

 from the familiar name, but are determined rather by the Aveather, 

 the health, the food, or bj' some i)eriodicity of the sj^stem. From five 

 to seven attacks usually result in blindness, and then the second eye 

 is liable to be attacked until it also is ruined. 



In the intervals between the attacks some remaining symi)toms 

 betray the condition, and these become more marked after each suc- 

 cessive access of disease. Even after the first attack there is a bluish 

 ring round the margin of the transj)arent cornea. The eye seems 

 smaller than the other, at first because it is retracted in its socket, 

 and often after several attacks because of actual shrinkage (atrophy). 

 The upxDer eyelid, in place of presenting a uniform, continuous arch, 

 has about one-third from its inner angle an abrupt bend, caused by 

 the contraction of the levator muscle. The front of the iris has 

 exchanged some of its dark, clear brilliancy for a lusterless j'ellow, 

 and the depth of the eye presents more or less of the greenish yellow 

 shade. The pupil remains a little contracted, except in advanced and 

 aggravated cases, when, Avith opaque lens, it is widelj- dilated. If one 

 eye only has suffered, as is common, the contrast in these respects 

 with the sound eye is all the more characteristic. Another feature is 



