De balneis et thermis naturalibus omnibus Italiae.

The second printed book on balneology. Savonarola took a skeptical approach to the subject, relying on his own observations and rejecting the notion that baths owed their virtues to occult or supernatural properties. Included in his work is the first recorded instance of a clock being used to regulate an actual, purposive experiment—in this case, a comparison of the water temperatures of two Italian hot springs.
ISTC is0029000. Digital facsimile from Bayerische Staatsbibliothek at this link.