Theses hasce de renum vesicaeque calculo

Among the many and great afflictions of the kidneys and bladder by which they are tormented, there is lithiasis, by which men are afflicted almost more severely and more frequently than by the others.

Lithiasis is an affliction, agonizing with pain and obstructions to urination, arising from a calculus obstructing or irritating the urinary passages.

It varies, however, in that one stone may be lodged in the kidneys themselves or in the ureters, and another in the bladder or its neck; the former is called a calculus of the kidneys, the latter of the bladder.

The proximate causes of this are twofold: the one efficient, the other material.

The efficient cause of calculi in our bodies is indeed a manifest heat, though it is not always necessarily vehement and intense.

The school of Physicians asserts that a thick, viscous, and tenacious humor provides the material for this; nevertheless, reason and experience themselves testify that an earthy matter is present in the serum, from which small grains of sand are generated, and from these, when compacted, stones are formed.

Since thick, pure phlegm cannot reach the kidneys at all, while the serum itself continually bathes them.

In which one may clearly see an earthy substance to be present, from the fact that if urine stands for some time, it deposits such matter as is accustomed to adhere to the chamber pot.

This usually takes its origin from heavy and salty foods, as the antecedent cause.

There is also an inherent sandy constitution of the kidneys, according to Fernel, on account of which this disease is also frequently hereditary.

The signs of the generation of a stone in the kidneys are: urine that is pure and watery from the start, in which the sandy particles previously seen are no longer excreted but are retained.