"How much of Africa had been explored out of simple hatred?" Peter Stark wonders in At the Mercy of the River: An Exploration of the Last African Wilderness (Ballantine, $24.95). He goes on to tell the loathsome story of King John I of Portugal, who in 1415 sent an invading force to Ceuta, "on the northern tip of Africa just across from Gibraltar." The monarch's rationale? "By killing Moors he would be 'washing his hands in the blood of the infidel' and cleansing himself of slaying fellow Christians in his previous battles with the Christian king of Castile."

Stark's own motive in going to Africa was more benevolent: He joined a small expedition determined to paddle the length of the Lugenda in Mozambique, 750 kilometers' worth of almost uncharted river. On the way, Stark had stomach problems, the group encountered locals carrying an AK-47, and rapids that had looked merely challenging from a scouting plane turned out to be seething maelstroms. Oh, and the author philosophized a good deal about the nature of exploring and the meaning of wilderness, which he identifies as a "sense of utter animal nakedness. Absolute vulnerability. I was in the midst of wilderness, and I didn't like it at all."

Paul Stoller's Gallery Bundu: A Story About an African Past (Univ. of Chicago; paperback, $15) is a novel about a different kind of African foray: David Lyons, the owner of the eponymous gallery of African art in New York, went to Niger in the late 1960s as an English-teaching Peace Corps volunteer. While there, he had an affair with a woman who, as he was about to leave, told him she was pregnant and the child was probably his. He left all the same but salved his conscience by sending periodic payments to the woman and child. Now, as a successful middle-aged businessman, David goes back to Africa, looking for the two people he walked out on. While there, he picks up the weaving he had learned in the country a generation earlier, a pastime that has new meaning for him: "I now realized that I had been blind to the central truth of weaving: one wove to remake a world that is continuously torn apart by jealousy, resentment, and bad faith."

-- Dennis Drabelle