When Cooper's most memorable hero, Leatherstocking, started an American tradition by setting off into the sunset in The Pioneers, one early reader said of his departure, "I longed to go with him." American readers couldn't get enough of the Leatherstocking saga (collected in two Library of America volumes) and, fourteen years after he portrayed the death of Natty Bumppo in The Prairie, Cooper brought him back in The Pathfinder,...