DISEASES OP THE EYEWDS. 261 



or puckering. The simplest mode of holding them together is by a 

 series of sharp pins passed through the lips of the wound at intervals 

 of not over a third of an inch, and held together by a thread twisted 

 around each pin in the form of the figure 8, and carried obliquely 

 from pin to pin in two directions, so as to prevent gaping of the 

 wound in the intervals. The points of the pins may then be cut off 

 with scissors, and the wound- may be wet twice a day with a weak 

 solution of carbolic acid. 



Though cruelly excised for alleged " hooks," when itself perfectly 

 healthy in the various diseases which lead to retraction of the eye into 

 its socket, the haw may, like other bodily structures, be itself the seat 

 of actual disease. The pigmentary black tumors of white horses and 

 soft (encephaloid) cancer may attack this part primarily or extend to 

 it from the eyeball or eyelids ; hairs have been found growing from its 

 svirface; and the mucous membrane covering it becomes inflamed in 

 common with that covering the front of the eye. These inflamma- 

 tions are but a phase of the inflammation of the external structures 

 of the eye, and demand no particular notice nor special treatment. 

 The tumors lead to such irregular enlargement and distortion of the 

 haw that the condition is not to be confounded with the simple pro- 

 jection of the healthy structure over the eye when the lids are pushed 

 apart with the finger and thumb, and the same remark applies to the 

 ulceration, or caries, of the cartilage. In the latter case, besides the 

 swelling and distortion of the haw, there is this peculiarity, that in 

 the mids't of the red inflamed mass there appears a white line or mass 

 formed by the exposed edge of the ulcerating cartilage. The animal 

 having been thrown and properly fixed, an assistant holds the eyelids 

 apart while the operator seizes the haw with forceps or hook and care- 

 fully dissects it out with blunt-pointed scissors. The eye is then 

 covered with a cloth, kept wet with an eyewash, as for external 

 ophthalmia. 



OBSTETJCTION OF THE LACHRYMAL APPARATUS, OR WATERING EYE. 



The escape of tears on the side of the cheek is a symptom of exter- 

 nal inflammation of the eye, but it may also occur from any disease 

 of the lachrymal apparatus which interferes with the normal prog- 

 ress of the tears to the nose. Hence, in all cases when this symptom 

 is not attended by special redness or swelling of the eyelids, it is well 

 to examine the lachrymal apparatus. In some instances the orifice of 

 the lachrymal duct on the floor of the nasal chamber and close to its 

 anterior outlet will be found blocked by a portion of dry muco-puru- 

 lent matter, on the removal of which tears may begin to escape. This 

 implies an inflammation of the canal, which may be helped by occa- 



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