FOUCAULT'S PENDULUM
by Umberto Eco
Translated by William Weaver
Harcourt Brace Jovanovich
641 pages; $22.95
A man named Casaubon hides after closing time in a Paris museum called the Conservatoire des Arts et Metiers. Nearby, an enormous pendulum swings silently in the gathering darkness, mute testimony, as a 19th century French scientist named Foucault first demonstrated, to the rotation of the earth. Casaubon is here because he suspects something terrible will happen before dawn. If he is correct, then he and two friends, playful inventors of a plot to rule the world, do not have long to live. In their machinations,...