-THE ARTERIES OF THE NECK. il7 



internal enters the skull and is the main source whence the braia 

 derives its arterial blood. Smaller streams are sent to the brain from 

 the vertebral arteries, which, defended and partly concealed in canals 

 formed for them in the bones of the neck, after having fed the neigh- 

 boring parts, likewise expend the remainder on the brain, entering 

 by the great foramen, through which the spinal chord escapes. A 

 third and smaller branch, leaving the main trunk high up in the neck, 

 sends a small vessel to the brain, under the title of the occipital 

 artery. 



We can conceive of very few, if any, cases in which it would be 

 either necessary or advisable to bleed from an artery in the ox. The 

 temporal is, in a manner, out of reach ; and the artery of the fore- 

 head is so defended by its bony canal, as not to be easily got at ; 

 besides which, in bleeding from an artery, there will always be 

 extreme difficulty either in getting the quantity of blood wanted, on 

 account of the contraction of the vessel, or of stopping the haemor- 

 rhage, if the blood flow freely. 



There is one circumstance which will strike every one, and that is 

 — except the larger vessels immediately from the heart — the sraallness 

 of the arteries, and the largeness of the veins. What enormous ves- 

 sels are the jugulars and milk veins !> And what a torrent of blood 

 will pour from them if a large incision be made ! We shall bear 

 this in mind as we pass on. 



The submaxillary artery has been already described (fig. 27, pp. 

 202 and 205,) pursuing its course anteriorily, to bury itself beneath 

 the angle of the lov/er jaw, whence it speedily emerges again, and 

 close to the angle of the jaw. This should be remembered when 

 we are feeling for the pulse. It occurs under some circumstances of 

 disease, that it is difficult, or impossible, to ascertain the pulse at the 

 jaw, and should, therefore, teach us to go at once to the side when 

 there is any difficulty about the jaw. 



The temporal artery is much larger, because it has a great surface 

 to ramify upon and to feed : the figure will point out the spot at 

 which the pulse will usually be most conveniently felt. 



The anterior auricular artery is also large. It supplies not only the 

 anterior muscles of the ear, but also the temporal muscle, deeply 

 lodged in the temporal fossa. The pulse may be very readily felt by 

 means of it, and perhaps more readily than from the temporal. 



The superciliary artery, escaping from the foramen above the orbit 

 of the eye, is a considerable one. It forms two branches, of which 

 one goes to the root of the horn, and contributes to the vascularity 

 and nutriment of that part. The other descends downward, on tho 

 side of the face. 



The occipital artery is small, the brain of the ox, which a branch 

 of this artery supplies, being small compared to his size. 



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