DISEASES OF THE CORNEA 



415 



opacity of the cornea to cloud-like spots, dull white, chalky white, 

 or pigmented (Fig. 141). Calomel blown on the cornea by means 

 of a small cylinder of paper or a quill, salves, such as calomel 

 1 part and petroleum salve 4 parts; a piece the size of a pea is put 

 on the cornea and the lid gently massaged for several minutes. Calo- 

 mel and sugar of milk, equal parts, is also used; a small portion is put on 

 the eye by means of a camel's hair pencil, and the lid is gently massaged, 

 moving the lid by a circular motion of the finger for ten or fifteen minutes. 

 Red and yellow precipitate of mercury ointment or a few drops of iodide 

 of potassium, 3 per cent, solution, are sometimes found useful as an ab- 

 sorbent. When there are elevations or encrustations on the cornea due 

 to the deposit of chemicals from eye washes, they can be curetted 

 (scraped) off by means of a sharp knife. The cornea is, as a result of this 



Fig. 141. — Leucoma. 



irritation, apt to be slightly denser in its structure. Certain permanent 

 opacities of the cornea that disfigure the animal can be modified by 

 means of tattooing; the eye is cocained and a tattooing needle used. 

 The punctures are made in an oblique direction to avoid any possibility 

 of puncturing the cornea; a great number of small punctures are made 

 in the body of the opacity, covering its entire surface, and sepia or india 

 ink rubbed into punctures. This is done by putting the color in solution 

 on the eye and massaging the lid for ten or fifteen minutes at a time. 

 This tattooing may have to be repeated several times. 



