Calculi

Concretions of various kinds which occur occasionally in the hollow organs and canals of the body. Disease of the organs acts as predisposing cause, and in the case of bladder stones limestone waters seem to produce them. In the bladder they are composed of ammonio-phosphates of lime and magnesia, oxalate of lime, uric acid, and rarely of cystine; in the kidneys, of uric acid or oxalate of lime; in the gall bladder, of cholesterine; occasionally in the salivary ducts and nasal pa ages, of phosphate and carbonate of lime; in the appendix cæcum, of fæces, sometimes covered with carbonate and phosphate of lime and of albuminous mucus.