100 DISEASES OF THE HOKSE. 



water freely, and let the food be only such as contains a large propor- 

 tion of liquid, gruels, mashes, turnips, beets, applas, pumpkins, 

 ensilage, succulent grasses, etc. If the acute stage has passed and 

 the presence of the calculus is manifested only by the frequent passage 

 of urine with gritty particles, by stiffness of the loins and hind limbs, 

 and by tenderness to pressure, the most promising resort is a long run 

 at pasture where the grasses are fresh and succulent. The long- 

 continued secretion of a watery urine will sometimes cause the break- 

 ing down of a calculus, as the imbibition of the less dense fluid by the 

 organic spongelike framework of the calculus causes it to swell and 

 thus lessens its cohesion. The same end is sought by the long-con- 

 tinued use of alkalies (carbonate of potassium), and of acids 

 (muriatic), each acting in a different way to alter the density and 

 cohesion of the stone. But it is only excej^tionally that any of these 

 methods is entirely satisfactory. If inflammation of the kidneys 

 develops, treat as advised under that head. 



Stone in the hladder {vesical calculus, or cystic calculus). — These 

 may be of any size up to over a pound in weight. One variety is 

 rough and crystalline and has a yellowish white or deep-brown color. 

 These contain about 87 per cent carbonate of lime, the remainder 

 being carbonate of magnesia, oxalate of lime, and organic matter. 

 The phosphatic calculi are smooth and white and formed of thin 

 concentric layers of great hardness extending from the nucleus out- 

 ward. Besides the phosphate of lime these contain the carbonates of 

 lime and magnesia and organic matter. In some cases the bladder 

 contains and may be even distended by a soft pultaceous mass made 

 up of minute round granules of carbonates of lime and magnesia. 

 This, when removed and dried, makes a firm, white, and stony mass. 

 Sometimes this magma is condensed into a solid mass in the bladder 

 by reason of the binding action of the mucus and other organic 

 matter, and then forms a conglomerate stone of nearly uniform con- 

 sistency and without stratification. 



Syni ptoms of stone in the hladdei\ — The symptoms of stone in the 

 bladder are more obvious than those of renal calculus. The rough 

 mulberry calculi especially lead to irritation of the mucous membrane 

 and frequent passing of urine in small quantities and often mingled 

 with mucus or blood or containing minute gritty particles. At times 

 the flow is suddenly arrested, though the animal continues to strain 

 and the bladder is not quite emptied. In the smooth phosphatic 

 variety the irritation is much less marked and may even be altogether 

 absent. With the pultaceous deposit in the bladder there is incon- 

 tinence of urine, which dribbles away continually and keeps the hair 

 on the inner side of the thighs matted with soft magma. In all cases 

 alike the calculus maj'^ be felt by the examination of the bladder with 

 the oiled hand in the rectum. The pear-shaped outline of the bladder 



