PRALAYA, or doomsday in the Hindu eschatological scheme, comes at the end of the fourth and worst of the four ages, or yugas, at the end of each kalpa, or day of Brahmā. The Purāṇas, which describe this process in great detail, differ as to the precise length of time that this process requires, but the scale is always astronomical, involving hundreds of thousands of years. At the end of the kalpa, the heat of the sun becomes so intense that it dries up the whole earth and sets the three worlds (heaven, earth, and the underworld) on fire; when they have been entirely consumed, enormous clouds appear and rain falls for hundreds of years, deluging the whole world until the waters inundate heaven and all is reduced to the primeval ocean of chaos. In anthropomorphic terms, this is the moment when Brahmā, whose waking moments...