60 . SOUNDNESS IN HORSES. 



principally, on the upper margin of the pupil) are regular ; 

 for it sometimes happens that one or more of them be- 

 come torn away from the iris, and may, consequently, 

 affect the vision. The cornea should be carefully ex- 

 amined, to see if there are any scars or opacities on it ; 

 and, while holding the candle or lamp a little to one 

 side, and raised or depressed, as the case may require, we 

 should look through the pupil, and try to detect any 

 speck on the lens or its capsule, the fact of the existence 

 of which should be sufficient to cause the rejection of the 

 horse for cataract. We may also regard the eye from 

 one side, while holding the taper to the front. To further 

 test the condition of the lens, we may hold the light a 

 little to one side of the eye, and look for the three 

 images of the flame that are^to be seen in a healthy eye; 

 the first and brightest being reflected from the cornea ; 

 the second and largest from the front surface of the lens ; 

 and the third, which is small, dim, and placed upside- 

 down, from the back of the lens. If the flame be slowly 

 moved from one side to the other, the first two images 

 will follow the direction of the candle, while the third 

 and reversed one will go the opposite way. If a cataract 

 be present and complete, the third image will be absent. 

 If it be only partial, the view of the third image will be 

 found to be obstructed when the light falls on the 

 opacity. The ophthalmoscope might frequently be used 

 with benefit in the examination of the eyes of the horse. 



