"The Sea at Mombasa is as blue as cornflower," wrote Isak Dinesen, "and, outside the inlet to the harbour, the long breakers of the Indian Ocean draw a thin crooked white line, and give out a low thunder even in the calmest weather." Vast, untamed, mysterious, and profoundly beautiful, Africa has always exerted a powerful sway over its Western admirers. And the dual nature of the Dark Continent reflected in Dinesen's lines--a paradise with a dark,...