500 SPECIFIC OR PERIODICAL OPHTHALMIA. 



twelve hours, it would again have almost become transpa- 

 rent, without any apparent medical agency. 



In the above detail of symptoms, it is the active inflam- 

 matory state which has been described, and is frequently so 

 sudden in its attack as to gain almost its "topmost height " 

 in a few hours. It is not, however, in every instance, thus 

 violent, nor thus sudden ; on the contrary, it sometimes 

 approaches more slowly, when the impatience of light is 

 not remarkable, and amounts only to a winking of the lids, 

 and moisture from tears, when brought into the full glare : 

 the globe of the eye looks rather yellow than red, and 

 within, it is only slightly disturbed by a discoloured muddi- 

 ness. The haw is then hardly apparent, the eyelids are less 

 swollen or gorged, and the tears pass in their natural 

 channel ; the eye or eyes remain without much variation 

 many days, and sometimes even weeks. This apparent 

 mildness of symptoms is not, however, a prognostic of a 

 less formidable disease, for this proves usually an obstinate 

 case, and may be eventually fatal to vision. 



Specific ophthalmia commonly attacks only one eye in the 

 horse, leaving the other totally unaffected, orat most only sym- 

 pathetically involved. Worthy of remark, is the complete 

 and sudden metastasis which often takes place in this disease. 

 From being in a very aggravated state of inflammation in 

 one eye, it will suddenly shift its seat to the other, leaving 

 the original much amended or nearly well ; and it will not 

 only thus change about from eye to eye, but may likewise 

 either spring from, or be transferred to, other organs. 



The periodical nature of the complaint is such, that, 

 having once made its appearance, there is almost a cer- 

 tainty of a recurrence of its attacks ; its appearance, how- 

 ever, cannot be anticipated : it may be absent for months, 

 or it may return in a week or two. It is always observed, 

 that the first of these inflammatory attacks, however violent, 

 having arrived at its height, usually gives way to medical 

 treatment ; or the disease leaves the horse of its own accord, 

 and the eyes recover nearly their former appearance : upon 

 a narrow inspection, there may be observed either some 

 small opaque spots within the lens, or the general cornea 

 will not be so distinctly clear as it was before the appearance 

 of the disease ; or even should the centre of the cornea be 



