Historian of science Bill Newman says that Isaac Newton’s alchemical notebooks are like a gigantic jigsaw puzzle. But as you’ll see as you peruse the 300-year-old manuscript at left, this puzzle is no child’s play—more like an enigma wrapped in a mystery riddled with a number of misleading clues. With Bill Newman’s help, we’ve "decoded" a page from one of these manuscripts. To orient yourself to the bewildering world of 17th-century alchemy, we recommend you first read our interview with Bill Newman before plunging into the manuscript.—Susan K. Lewis