roject Mercury, and an additional five members of the team, provides Jon with the launching pad for a novel about the making of an astronaut, and the story of a friendship which dictated the destinations of two lives. Duke Dalmead and Matt Crispin grew up together on Cape Cod. As boys and well into manhood, it was Duke who led, with his restless ambition and cool independence. Duke went first to M.I.T., then with the outbreak of the war urged Matt to follow him into the air . In Australia, Matt found Jane; in England, Duke rediscovered Cleo--and after the war each brought his woman home to America, to very different marriages. After a try at M.I.T., the men return to flying, and their future course is set as they move from a private one-plane outfit that flies the Berlin airlift to military duty in the Korean conflict, test piloting in California, and the space program at angley, then Cape Canaveral. The interplay of personal and professional lives remains crucial, the friendship intact through life-and-death flying episodes until closes Duke out after his sister Anne, unable to take a rebuff from Duke, kills . Duke takes on the guilt of her death and has himself scratched from the , discarding the glory he has always sought. A final reconciliation occurs when Duke finds Matt, downed from his flight, in the Australian bush. A curious, completely convincing reversal in roles, lies at the root of the story of the two charioteers, whose fates are reeled out with calm capability and satisfying seriousness.