Propositiones de lithiasi tōn nephrōn

This is often the reason why this vice is hereditary, and it does not arise, as some think, because of a property of the kidneys that converts matter into stone by an occult virtue. Indeed, if it happened because of such a property of the kidneys, the entire kidneys would turn to stone very quickly.

XIII.
The natural density or narrowness of the passages is sufficient, through which the attracted juice is carried and sends the segregated urine to the bladder. Then also the weakness of the expulsive faculty, from whatever source it arises, if suitable matter is present.

XIV.
Stones are not generated by a cold intemperance, because in a living animal there cannot be so much cold as to be able to coagulate juices into stones so hard, which the author of the book On Renal Affections proves by the example of external things.

XV.
Acquired heat sometimes arises from internal causes, sometimes from external ones.

XVI.
Nephritis inflammation of the kidney is distinguished from colicky pain, as Galen testifies in On Afflicted Parts book 6, chapter 1, because in nephritis the pain is fixed, remaining in the side, sometimes extending into the bladder, and the urine is thin at the beginning, or turbid and suppressed. In colicky pain, the pain is unstable and wandering, pressing now in this part, now in that, sometimes raging in a place higher than the kidneys or around the navel. Finally, colicky pains are much more mitigated by soothing clysters than are nephritic ones.

XVII.
Which kidney is affected is known from the location of the pain, which is fixed constantly in one side or the other; and the stable pain infests the right side if...