Britain stays out of World War Two and lets the Nazis and the Japanese conquer Europe, Russia and Asia. In true 'belt and braces' style, a spinning rocket, powered by solid fuel, is built to claim back some national pride by trying to reach the moon first in 1950. Flown with dash by an public school boy, the brainy, but socially inferior, engineer has to use observation and a slide rule to navigate. One of the best alternate space exploration stories around, it gets the technology and social milieux just right. ( )