2 Early History and Habits 



their constant state of liberty, and their roving habits, in 

 order to obtain food and water, they are inured to fatigue, 

 and can bear an enormous amount of long-continued fast 

 work, without failing under it, and without that training 

 which the domesticated animal must have. The walk and 

 the gallop are the horse's natural paces, and all others are 

 acquired; but nothing can exceed the fiery animation and 

 elegance of movement of the free horse ; and in these two 

 paces art has done nothing to improve his form, except, 

 perhaps, in slightly increasing the speed of the latter. In 

 all countries, and in every age, the horse feeds upon grain 

 or grass, though it is said that in Arabia he is occasionally 

 supported upon camel's milk, when food such as he usually 

 lives upon is not to be had. 



It may be useful to specify the terms employed to de- 

 scribe the principal parts of the horse. These details will 

 not prove altogether superfluous, as some of the words we 

 are about to explain not unfrequently occur in conversa- 

 tion. 



The two parts of the head of the horse which corre- 

 spond to the temples, or temporals in man, are above the 

 eyes. The orbit is the bony cavity designed to receive 

 and protect the eyeball, with its needful muscles, nerves, 

 and blood-vessels, &c. At the inner angle is situate the 

 haw, or membranes nictitans (a), a cartilaginous plate, 

 which forms the mechanism enabling the horse, especially, 

 to remove offending substances. He also in common 

 with other nocturnal animals possesses the power of 

 seeing objects clearly in the twilight and comparative 

 darkness. This is conferred by an arrangement within 

 and at the back of the eye, known as the tapetum 

 lucidum, or green carpet. The eyepits (p) are hollows 

 above the eyes, covered by skin, intended to provide for 

 motion of the eyeball during the action of its muscles, as 

 well as those engaged in mastication. 



The face (c) is that part of the head which extends 

 from the eyes to the nostrils. The forehead is above the 

 eyes. These are seen by the observer as he stands in 

 the front of the animal. 



The neck of the horse is designated by the term crest 



