In his poem to the hesitating purchaser of Treasure Island, Robert Louis Stevenson names Cooper among the great romancers he has emulated, describing him as “ Cooper of the wood and wave.” That phrase names both the aspect of Cooper's work which interests me, the adventure novels, and the major subdivision of that aspect. I am not, that is, going to discuss the non-fiction, and among the fiction I am not going to discuss the Effingham or the Littlepage novels, nor even the historical novels as such. I'm going to concentrate upon the Leatherstocking saga, seen as forest books, and upon sea fiction like Afloat and Ashore, The Pilot, and The Sea Lions. I want to point out differences between the two sub-genres in fictional art and fictional success, and to try to explain those differences in terms of social and political forces. But I also want to stress the unity of the two, which is to say Cooper's identity as an adventure novelist. Because we lack a critical vocabulary for that genre, critics have, it seems to me, failed to take proper account of one of the major forms and forces of our literature. And this is particularly unfortunate in American Studies, because adventure has been so large a part of American culture.