202 
MANUAL OF MODERN FARRIERY. 
muscle, d d, called the retractor, is added ; it arises from 
the edge of the foramen, through which the optic-nerve 
enters the orbit. The use of this muscle is to support the 
eye generally, or when it is suddenly called into great 
action, and aided by the straight muscles, it draws the eye 
back out of the reach of danger, and in the act of drawing 
it back it forces the haw to protrude in the manner already 
described, as an additional defence. The cornea, i, is the 
only visible part of the eyeball of a horse, or at least it 
should be; and it is said that where much white is seen, 
that it is an indication of bad temper. The pupil, k, in 
the horse differs in form from that of all other animals. 
It is of an elongated, oblong, ovate form, and placed trans¬ 
versely, as represented in fig. 4, plate iii. 
The eye is a very important organ in the horse. It ought 
to be large and rather prominent; the eyelid should be fine 
and thin. This thinness is for the purpose of preventing 
pressure, and at the same time to give more extensive and 
easy motion. 
The horse is devoid of eyebrows, and the eyelashes are 
singularly arranged. The rows of hairs are longest and 
most numerous on the upper lid, and especially towards the 
outer or temporal corner, because the light falls on the eye 
from above ; and as he stands, especially when he is grazing, 
us well as from the lateral situation of the eyes, the greater 
portion of the light, the attacks of insects, and the trick¬ 
ling down of moisture, is chiefly from the outside. To¬ 
wards the inner corner of the eye there are hardly any 
eyelashes, because there is little or no danger from below, 
and as little light is thrown from below, the eyelashes are 
thin and short. While horses are grazing, insects may find 
their way to the eye towards the inner angle, the principal 
or only hair is found on the lower lid. All of which most 
