232 THE SALIVARY GLANDS. 



a terrible jerk whenever the horse was disposed to be rebellious. The 

 animal, under such torture, became unmanageable, and the man who held 

 the chain sawing away with all his strength, the tongue was completely 

 cut off at the point which separates its base from the free portion of it. 

 The wound healed favourably, and he was soon able to manage a mash. 

 After that some hay was given to him in small quantities. He took it and 

 formed it into a kind of pellet with his lips, and then, pressing it against 

 the bottom of his manger, h e gradually forced it sufl&ciently back into the 

 mouth to be enabled to seize it with his grinders. 



Another horse came to an untimely end in a singular way. He had 

 scarcely eaten anything for three weeks. He seemed to be unable to 

 swallow. The channel beneath the lower jaw had much enlargement 

 about it. There was not any knovra cause for this, nor any account of 

 violence done to the tongue. At length a tumour appeared under the jaw, 

 Mr. Young of Muirhead punctured it, and a considerable quantity of 

 purulent matter escaped. The horse could drink his gruel after this, but 

 not take any solid food. A week afterwards he was found dead. Upon 

 separating the head from the trunk, and cutting transversely upon the 

 tongue, neai'ly opposite to the second grinder, a needle was found lying 

 longitudinally, and which had penetrated from the side to the inferior 

 portion of the tongue. It was an inch and a quarter in length, and the 

 neighbouring substance Avas in a state of gangTene. 



Vesicles Avill sometimes appear along the under side of the tongue, which 

 will increase to a considerable size. The tongue itself will be much enlarged, 

 the animal Avill be unable to swallow, and a great quantity of ropy saliva 

 ■will drivel from the mouth. This disease often exists -without the nature 

 of it being suspected. If the mouth is opened, one large bladder, or a 

 succession of bladders, of a purple hue, will be seen extending along the 

 whole of the under side of the tongue. If they are lanced freely and 

 deeply, from end to end, the swelling will very rapidly abate, and any 

 little fever that remains may be subdued by cooling medicine. A mild 

 solution of alum, applied by means of a small piece of sponge frequently 

 during the day, will accelerate the cure. The cause of this disease is not 

 clearly known, 



THE SALIVARY GLANDS. 



In order that the food may be properly comminuted preparatory to 

 digestion, it is necessary that it should be previously moistened. The food 

 of the stabled horse, however, is dry, and his meal is generally concluded 

 without any fluid being offered to him. Nature has made a provision for 

 this. She has placed in the neighbourhood of the mouth various glands 

 to secrete, and that plentifully, a limpid fluid, somewhat saHne to the taste. 

 This fluid is conveyed from the glands iiito the mouth, by various ducts, 

 in the act of chewing, and, being mixed with the food, renders it more 

 easily ground, more easily passed afterwards into the stomach, and better 

 fitted for digestion. 



The principal of these is the parotid gland (see cut, p. 199). It is placed 

 in the hollow which extends from the root of the ear to the angle of the 

 lower jaw. The portion of it, q, is represented as turned up, to show the 

 situation of the blood-vessels underneath. In almost every case of cold 

 connected vdth sore throat, an enlargement of the parotid gland is evident 

 to the feeling, and even to the eye. It is composed of numerous small 

 glands connected together, and a minute tube proceeding from each, to 

 carry away the secreted fluid. These tubes unite in one common duct. 

 At the letter u, the parotid duct is seen to pass under the angle of the 

 lower jaw, together with the submaxillary artery, and a branch of the 



