This Wheel of Urine is from Ullrich Pinder's Epiphanie Medicorum (1506). It was used to diagnose disease based on characteristics of the patient's piss, including its taste. Urinalysis is common today, of course. Well, not the tasting part. "The Urine Wheel" (SciAm)
David Pescovitz is Boing Boing's co-editor/managing partner. He's also a research director at Institute for the Future. On Instagram, he's @pesco.