OF THE NOSE AND MOUTH. 197 



This cavity is divided into two parts by a cartilage called the Se2)tu))i 

 (d, d). It is of considerable thickness and strength, and divides the 



ca\'ity of the nose into two equal parts. It is placed in the centre for the 

 purpose of strength, and it is formed of cartilage, in order that, by its 

 gradually yielding resistance, it may neutralise almost any force that may 

 be applied to it. 



When we open the nostril, we see the membrane by which the cartilage, 

 and the whole of the cavity of the nose, is lined, and by the colour of which, 

 much more than by that of the lining of the eyelids, we jiidge of the degree 

 of fever, and particularly of inflammatioai of the lungs, or any of the air- 

 passages. The above cut shows the ramifications of the blood-vessels, 

 both arterial and venous, on the membrane of the nose. It beautifully 

 accounts for the accurate connection which we trace between the colour 

 of the nasal membrane, and various diseases or states of the circulation. 

 By the sore places or ulcerations discovered on this membrane, we 

 likewise determine respecting the existence of glanders ; and the inter- 

 position of the septum is a wise and benevolent provision to hinder the 

 spread of the mischief, by cutting off all communication with the neigh- 

 boui'ing parts, and also to preserve one nostril pervious, when the other is 

 diseased or obstructed. The nasal cavity is, on either side, occupied by 

 two bones, which, from their being rolled up somewhat in the form of a 

 turban, are called the tnrhinated or turhan-shaped bones. They are as 

 thin as gauze, and pei-forated like gauze, with a thousand holes. Between 

 them are left sufficient passages for the air. 



If they were unrolled, they would present a very considerable surface ; 

 and on every part of them is spread the substance or pulp of the oJfacforj/ 

 or first pair of nerves. These bones, lined with delicate membranes and 

 covered by the olfactory nerves, are the seat of smell ; and they are thus 

 expanded, because the sense of smell in the horse must, to a very consider- 

 able degree, supply the place of the sense of touch and the lessons of ex- 

 perience in the human being. By this alone he is enabled to select, amongst 

 the nutritive and poisonous herbage of the meadow, that which would 

 suppoi^t and not destroy him. The troops of wild horses are said to smell 

 the approach of an enemy at a very considerable distance. In his domestic 

 state, the horse does not examine the different food which is placed before 

 him with his eye, but with his nose ; and if the smell displeases him no 

 coaxing will induce him to eat. He examines a stranger by the smell, and, 

 by very intelligible signs, expresses the opinion which he forms of him by 

 this inquisition. The horse will evidentally recognise his favourite groom 

 when he has nothing else to indicate his approach but the sense of smell. 

 These cavities are likewise organs of voice. The sound reverberates 



