The historical scene for the discovery of Archimedes' principle is invested with slight humor and peopled with actual and fictional characters to dramatize his insight. Absent-minded Archimedes forgets everyday things like eating and bathing until King Hiero assigns slave boy Xanthius to keep the scientist clean and fed. Xanthius manages to slip fruit to the solar system contemplater but getting him to the Baths is a problem until the slave convinces Archimedes to think about the king's crown (whether silver has been substituted for gold) at the same time. Archimedes gets in, the same amount of water spills over, and ""Eureka!"" A sprightly approach to a classic principle, and a likely lever to understanding.