NASAL GLEET. 373 



the lungs. It may be caused by fubiess of blood to the head, 

 or by a diseased or weak condition of the blood-vessels of 

 the mucous membrane of the air-passages of the head, as, for 

 instance, in the case of a naevus (p. 162) of that surface. Horses 

 appear to be more liable to this accident when they are pulling 

 hard, than when they are allowed to go freely. The only treatment 

 which I can advise, and which I have successfully employed in two 

 or three cases, is the injection up the nostril, of water of a tem- 

 perature of about 120° to 125° F. (p. 65). I can suggest no 

 preventive. The advisability of putting the animal on laxative 

 food, and gradually bringing him on to work again is self-evident. 



Nasal Gleet {Ozmm). 



DEFINITION. — A chronic and stinking discharge from the nose, 

 due to local causes. It is a symptom of disease. If we use the 

 term " ozrcna " (from oZ^r^, a bad smell) as a synon^-m for nasal 

 gleet, we must regard a foul odour as a necessary condition of the 

 discharge. We cannot put under this heading any somewhat 

 similar discharge arising from a general disease, as, for instance, 

 glanders. 



In the discharge of ozsena, there has been found two kinds of bacteria, 



namely, the bacillus fwHchis ozcenci of Hajf'k. and the Ixicillu^ smnragchnus 

 joetidns, of Eeiman, both of which produce a very offensive smell. The ques- 

 tion whether or not these organisms cause the disease has not yet been 

 answered. 



ANATOMY. — Under ordinary conditions, a horse breathes through his 

 nostrils, which are separated from each other by a cartilaginous partition. 

 In order to give a large surface for the attachment of muscles without greatly 

 adding to the weight, some of the bones of the horse's face are hollowed 

 out, so as to foi-m, on each side, five cavities (or sinuses) ; the three principal, 

 which are the only ones that need our attention here, being : the frontal, 

 the superior maxillary, and the inferior maxillary sinus. Tlie sinuses on one side 

 are divided from those on the other f^ide by a bony partition which runs down 

 the centre of the face from a little above the level of the eyes, and which may 

 be regarded as a continuation of the partition between the two nostrils. There 

 is a common passage by which all the sinuses open into the nose; and there 

 is a passage between the frontal sinus and the superior maxillary sinus. 

 Under ordinary circumstances, the inferior maxillary sinus does not com- 

 municate with any of the other minuses. The sinuses of the head are " blind " 

 cavities, through which, practically speaking, there is no passage of air. 

 The volume of air, however, appears to be changed by a slight alteration of 

 tension during breathing. 



The frontal sinus, on each side, lies underneath the bone of the forehead, 

 between the eye and the middle line of the face. It extends about three 

 inches above and about the same distance below a line joining the centres of 

 the two eyes and drawn across the forehead. 



The superior maxillary sinus, which is the largest, extends below the eye, 

 supposing the head to be held in a vertical position. 



The inferior maxillary sinus is usually separated by a bony partition from 

 the superior maxillary sinus, below which it extends not lower down than the 

 end of the zj'-gomatic ridge. 



