For more than a decade before World War I, Alfred Stieglitz lent much of his formidable energy to his public career as an editor, publisher, proselytizer, and art dealer. In the 1920s and 30s, he turned again to his own photography, exploring his personal world at Lake George, in the Adirondack mountains of New York, where he spent summers at a family farmhouse. He photographed the things around him--the landscape, the clouds overhead, the intimate...