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DISEASE OF THE LACHRYMAL PASSAGES. 



This malady, familiarly known as '' a watery eye," only now 

 and then occurs in horses. I may have met with some half-a- 

 dozen cases of it in my time ; some or all of which might have 

 been, in days gone by, called fistula lachrymalis : an appellation 

 which surgeons, better informed, of the present day, properly con- 

 fine to a form or stage of the disease that I cannot say I have ever 

 had occasion to treat in my own practice. The lachrymal apparatus 

 in animals is little subject to be out of repair. Its comparative sim- 

 plicity, the larger size of the passages and apertures, and the little 

 irregularity which happens in the lachrymal secretion, may serve 

 to account for this. 



In horses there seem to be three causes from which the tears, 

 instead of pursuing their natural course, may overflow the under 

 eyelid and trickle down the face. One is, an increase or super- 

 abundance of secretion ; and this mav arise either from some 

 external cause of irritation, or — what is commonly the case — ■ 

 from the presence of conjunctival inflammation: hence the 

 escape of tears upon the face becomes one of the symptoms of 

 ophthalmia. A second cause is, tumefaction of the eyelids, 

 occasioning diminution of the puncta lachrymalia, as well as, 

 perhaps, interfering somewhat with the regular course of the 

 tears into them. A third, and the grand cause, — it being the 

 one we are to regard as constituting the disease of which watery 

 eye is the sole or especial symptom, — is obstruction in the 

 lachrymal passages. The nature of this obstruction — so far as 

 our operations to relieve it have enabled us to judge of it — 

 appears to be similar to what constitutes a stricture in the urethra 

 in man; viz. a thickening of the lining membrane in some part 

 of the passages, in consequence, as it would seem, of some prior 

 or existing inflammation. That this membrane, which is of the 

 mucous class, appearing indeed to be a continuation of the con- 

 junctiva, is not infrequently inflamed, in its course through the 

 puncta at least, we may adduce as evidence the globule of 

 mucus so commonly seen lodging upon the puncta in catarrhal 

 and other inflammations about the head ; and if so often inflamed 



