32 DISEASES OF THE HORSE. 



the burned places, spread on cotton or linen rags for a 

 few days ; then dress the sores with simple ointment. 

 (See Medicines.) 



Bursa Mucosa Enlarged. — (See Spavin and Wind 



Galls.) 



Calculi. — Stone in the bladder. 



Cancers. — This is a hard tumor, malignant in its cha- 

 racter, at first small in size, but rapidly increases, sind 

 becomes ulcerated. The horse is not aifected with so 

 many varieties of cancerous growth as the ox and the 

 dog, and even man himself. Melanotic cancer is most 

 commonly seen in gray horses, or those that turn white 

 with age. A small hard tumor is usually seen under the 

 root of the tail, and about the anus. 



When tumors of this kind are seen on gray horses, it 

 may reasonably be expected that growths of the same 

 character will be found inside, on the spleen, stomach, 

 and liver. Horses so affected may work well for years, 

 and may not for a month. The tumors increase in 

 size, when cut into, they discharge a fluid as black as the 

 ink of the cuttle-fish. 



Causes. — As this disease is not seen in young gray 

 horses until after they have almost turned white, it may 

 be inferred that the cause results from the loss, or want 

 of the usual pigment, or coloring matter, which gives color 

 to the hair, thus depriving the animal of some protection 

 from the air or sun. I think, however, that the true 

 cause will be found to be, not in the loss of the coloring 

 matter, but of its transfer from the skin and hair to the 

 blood. Hence the inky color of the contents of the tu- 

 mors. This opinion, which is my own, is still farther cor- 

 roborated by the fact that if the pus be taken from an 



