This, then, was the man selected to lead 28 soldiers, two steam tractors and two heavy wooden boats through dense jungle from Cape Town to Lake Tanganyika, 2,500 miles and a 6,000-foot mountain away, in order to attack a much larger German force. Along the way, he made a point of trying to shoot the wild game, but almost always missed. Employing deadpan to delightful effect, Giles Foden has recreated this forgotten sideshow with aplomb in "Mimi and Toutou's Big Adventure."

Spicer took with him a second in command with canary yellow hair and an addiction to Worcestershire sauce; a former racing driver; two Highlanders in tartan; and a large supply of laxatives to dispense to the Africans, who apparently needed them (we are never told why). "You English have a genius for amateurism. That's what makes you so dangerous," one Belgian officer observed on encountering this motley crew. "Who but amateurs could have dreamed up an expedition like this?" Spicer named his attack boats Mimi and Toutou, the French for "meow" and "bowwow"; that was his favorite sort of joke.

The expedition did indeed prove dangerous, mostly to its participants, but the tiny flotilla somehow managed to capture one of the larger German ships and sink another. After this initial success, and having sewn himself a special vice admiral's flag, Spicer took to his bed with acute depression. He then wandered off for several months, nobody quite knew where.

This naval action in miniature did not alter the course of the war one jot, although the episode achieved immortality by inspiring C. S. Forester's novel "The African Queen," which in turn inspired the film of the same name starring Humphrey Bogart and Katharine Hepburn. Spicer returned to the admiralty (and thoroughly deserved anonymity) and spent the rest of his life lying about his exploits in Africa. Back on the banks of Lake Tanganyika, however, he was deified by the local tribe as "Bwana Chifunga-Tumbo," or Lord Bellycloth, in memory of his sartorial habits.

Foden is an accomplished novelist ("The Last King of Scotland"), and at times this story reads like an amalgam of Evelyn Waugh and Joseph Conrad. The truth is stranger than any fiction, and the pleasure of this book lies in its unbelievable veracity: the vivid re-creation of a lost time when eccentricity flourished and Britannia ruled the waves with a couple of little boats, a nice skirt and plenty of laxatives.