"Tile; D'apC: Tile; l. DpWTa ()coi 7rpo7rapod)w D'T}K, mi'. "between us and Goodness the gods have placed the sweat of our brows." This quote from Isiodos, the first lyrical poet, is jotted on a sheet of paper found among the papers of Heike Kamerlingh Onnes at the Boerhaave Museum, Leiden. On this same sheet, one can also read quotes from Schiller, Goethe, Shakespeare, Homer, Pindar and Dante. Each quote is for somebody or something. It appears to have been a game played at least by Ehrenfest and Crommelin -an unmistakable sign of these two physicists's deep culture. This particular quote...