40 LESSONS IN HORSE JUDGING. 



nerve, is a little body called the yellow spot {D 

 YS). 



26.— So much for the eyeball. Now let us see 

 how it is moved. The eyeball is imbedded in the 

 bony skull in a socket or case, partly of bone, 

 called the ^ orbit,' and being very delicate, this 

 bony orbit is filled with fat (Fig. 5, D), in which 

 the eyeball is imbedded. In old horses and dur- 

 ing illness this fat wastes away and allows the 

 eyeball to sink in its socket. There are five or 

 six muscles (Fig. 5, m m) to move the eye. The 

 ends of each muscle are attached, one to the bony 

 socket the other to the white outer tunic. We 

 have only two of these muscles depicted on the 

 diagram, but in real life one muscle is attached 

 to the upper part of the eye ; one to the lower; 

 one to the inner or nose side; one on the outer 

 side. So that when the top one contracts the eye 

 looks upwards, and so forth. There are two 

 other muscles obliquely i^Aeiced for rolling the eye, 

 but these we will not consider. The four muscles 

 named are called the four straight muscles, and 

 when they all contract at once, the eyeball is 

 pressed back into the socket and the ' haw ' (Fig. 

 5, D), which is a thin piece of grissle also imbed- 

 ded in the fat and whose edge can always be seen 

 on the inner angle of the eye, is pressed or 

 squeezed out of the fat and made to project over 

 the eye. 



27. — We must now turn our attention to the 

 front half of the eye as we see it in the living 

 animal, because it is this we have to examine 

 with the candle in the darkened stable. Still 



