CALCULI. 437 



with oil. If this does not succeed, scarify the mucous membrane 

 freely with a lancet, and encourage the bleeding by the application 

 of warm water, and, when the swelling has gone down, again 

 attempt to replace the part. Keep the animal for some days on 

 soft food, in which a pint of linseed oil may be given daily with 

 advantage. West's Uterine and Anal Clamp, made by Huish, is 

 a very useful instrument in these cases. 



Calculi and Concretions. 



NATURE. — In the bowels of the horse, especially in the large 

 intestine, and very rarely in the stomach, are sometimes found 

 balls of undigested material, which occasionally may attain to a 



Fig. 143, — Phosphatic calculus, 



diameter of five or six inches, or even more. As they become 

 larger and larger, they usually cause death eventually from ob- 

 struction and pain. They are of three varieties. (1) Phosphatic 

 calculi (Fig. 143), which looks like rounded and polished stones, 

 and are chiefly composed of phosphate of magnesia and lime. 

 They are of a much greater specific gravity than the other two 

 kinds. An ordinary weight for these calculi is 2 or 3 lbs. ; although 

 they may, in exceptional cases, be as heavy as 16 lbs., or even 

 more. The term " calculus '' {calx, chalk) should, correctly speak- 

 ing, be restricted to this variety; and the other two might be 

 called " concretions." When a phosphatic calculus is found in 

 the stomach, we may feel certain that it has been passed into that 

 organ from the intestines ; because the acid nature of the gastric 

 juice would prevent its formation in the stomach. (2) Oat-hair 



