Everyone knows that the ancient Egyptians were great mummifiers, and their sarcophagi and bandage-wrapped corpses are familiar images to us all. Yet across the vast sweep of history, we find many other great cultures in which the bodies of the dead were preserved as a matter of course. In coastal Peru were the Chinchorros, whose mummifying culture flowered several millennia before Egypt's, and in the Andes were the Chachapoyas, the 'Cloud People,'...