The ultimate jigsaw puzzle: You can't square a circle using a ruler and compass. But a pair of mathematical scissors will do the job by cutting the circle up into a huge but finite number of piecesFeatures
Forum: The Ppound in your pocket - Ian Stewart has finally sorted out his millions from his billionsForum
Review: Stalk the wild trajectory - Flights of fancy for Christmas begin with puzzles for the mind, soar with Balinese birds and British bats, then descend to the tomb and chaotic presentsBooks & Arts