Calculate velocity; explain the Maltese cross mechanism that's the basis of the motion picture project? and work out the ways different pendulums (including Foucault's famous version) swing. Every attractive page in master Ivan Moscovich's eleventh collection of brain-busters offers a tricky puzzle pleasure. Sixteen tiles show either a crowned frog or a crown prince: distribute them randomly on a game board, face down, and then see if you can come...