STONES IN THE KIDNEYS. 423 



It is evident that this is an evil we have little power to 

 combat : if a horse by passing a stone with his fa?ces indi- 

 cated a constitutional disposition to separate sabulous matter 

 from his food, and afterwards to concrete it by the mucus 

 of his bowels, the removal of a stone actually formed is 

 hopeless. The abdominal calculus generally has a nucleus, 

 or centre, consisting of a nail or stone. It is composed of 

 the triple phosphates, is generally round, and is easily 

 recognised, by its external surface bearing a polish so bright 

 as to seem the creation of art. Others are composed of the 

 fine hairs which cover the substance of the oat, and some, 

 called dung-balls, are formed by the feeces becoming com- 

 l^act. The first is usually found within the small intestines, 

 the two last invariably in the posterior bowels. 



STONES IN THE KIDNEYS, OR URINARY CALCULI. 



Urinary calculi are rather common in the horse; and 

 as we know these animals are much subject to disturbances 

 in their urinary secretion, we might think it very probable 

 that the silicious matter which is separated from the blood 

 should aggregate within the kidneys, as well as collect in 

 the bladder. We have better evidence than mere supposi- 

 tion, for urinary calculi have been found in horses who 

 have died under symptoms which might have been mistaken 

 for very acute enteritis. We may also suppose, that the 

 early accumulation would occasion irregular and diminished 

 secretion of urine ; followed, at length, by a bloody puru- 

 lent mixture with the water, until more active symptoms 

 should arise, and carry ofi^ the horse. Concretions within 

 the kidneys might be removed in their early state by reme- 

 dies tending to decompose them in the urinary pelvis. For 

 this purpose we have the mineral acids, of which the hydro- 

 chloric, as holding the silicious matter in solution, is to be 

 preferred. The mineral acids pass through the body un- 

 changed, being emitted with the urine in a state of purity. 

 Their power, therefore, is unimpaired, and they are ready 

 to act upon a calculus encountered within the kidney, with 

 all that energy which they would display were the substance 

 outside the animal. The action of the acid may, likewise, 

 be promoted, by injecting a drachm in a gallon of water 

 into the bladder daily. Two drachms of the hydrochloric 



