214 THE ANATOMY AND DISEASES OF THE NECK. 



standing, and the shoulder and arm are fixed points, this muscle will depress the 

 head and neck. 



The muscles of the neck are all in pairs. One of them is found on each side 

 of the neck, and the office which has been attributed to them can only be 

 accomplished when both act together; but supposing that one alone of the 

 elevating muscles should act, the head would be raised, but it would at the 

 same time be turned towards that side. If one only of the depressor muscles 

 were to act, the head would be bent downwards, but it would likewise be turned 

 towards that side. Then it will be easily seen that by this simple method of 

 having the muscles in pairs, provision is made for every kind of motion, upwards, 

 downwards, or on either side, for which the animal can possibly have occasion. 

 Little more of a practical nature could be said of the muscles of the neck, 

 although they are proper and interesting studies for the anatomist. 



This is the proper place to speak of the mane, that long hair which covers the 

 crest of the neck, and adds so much to the beauty of the animal. This, how- 

 ever, is not its only praise. In a wild state the horse has many battles to fight, 

 and his neck deprived of the mane would be a vulnerable part. The hair of the 

 mane, the tail, and the legs, is not shed in the same manner as that on the 

 body. It does not fall so regularly nor so often ; for if all were shed at once, the 

 parts would be left for a long time defenceless. 



The mane is generally dressed so as to lie on the right side some persons divide 

 it equally on both sides. For ponies it used to be cut off near the roots, only a 

 few stumps being left to stand perpendicularly. This was termed the hog-mane. 

 The groom sometimes bestows a great deal of pains in getting the mane of his 

 horse into good and fashionable order. It is wetted, and plaited, and loaded 

 with lead ; and every hair that is a little too long is pulled out. The mane and 

 tail of the heavy draught-horse are seldom thin, but on the well-bred horse the 

 thin well-arranged mane is very ornamental *. 



THE BLOOD-VESSELS OF THE NECK. 



Running down the under part of the neck are the principal blood-vessels 

 going to and returning from the head, with the windpipe and gullet. Our cut 

 could not give a view of the arteries that carry the blood from the heart to 

 the head, because they are too deeply seated. The external arteries are the 

 carotid, of which there are two. They ascend the neck on either side, close to 

 the windpipe, until they have reached the middle of the neck, where they some- 

 what diverge, and lie more deeply. They are covered by the sterno-maxillaris 

 muscle, which has been just described, and are separated from the jugulars by 

 a small portion of muscular substance. Having reached the larynx, they 

 divide into two branches, the external and the internal ; the first goes to ever)' 

 part of the face, and the second to the brain. 



The vertebral arteries run through canals in the bones of the neck, supplying 

 the neighbouring parts as they climb, and at length enter the skull at the large 

 hole in the occipital bone, and ramify on and supply the brain. 



Few cases can happen in which it would be either necessary or justifiable to 

 bleed from an artery. Even in mad-staggers the bleeding is more practicable, 

 safer, and more effectual, from the jugular vein than from the temporal or any 

 other artery. If an artery is opened in the direction in which it runs, there is 

 sometimes very great difficulty in stopping the bleeding ; it has even been neces- 

 sary to tie the vessel in order to accomplish this purpose. If the artery is cut 

 across, its coats are so elastic that the two ends are often immediately drawn 

 apart under the flesh at each side, and are thereby closed ; and after the first 

 gush of blood no more can be obtained. 



* Stevva* t's Stable CEconomy, p. 110. 



