<P>Clarence King's Survey, undertaken between 1867 and 1872, covered a vast swath of terrain, from the border of California eastward to the edge of the Great Plains. It was the first survey to include a full-time photographer—Timothy O'Sullivan—who produced about 450 finished photographs in large-format and smaller-format stereographs. O'Sullivan's images convey a distinct individual quality of perception, at once direct and laconic, as well as a perfect union of objective fact and personal interpretation. As such, O'Sullivan remains the most admired, studied, and debated photographer who worked on the great western surveys of the 19th century.<br><BR>This handsome and enlightening book aims to enrich and enlarge our understanding of O'Sullivan's pivotal body of western photographs by emphasizing the idea of <I>context</I>. This ambition encompasses several frames of reference: O'Sullivan's best-known images in relation to his larger body of survey work; the function his photographs served in relation to the survey's overall goals and methodologies; and the King Survey itself as a logical part of a complex and prolonged expeditionary endeavor. The volume also includes an essential catalogue raisonné of O'Sullivan's King Survey work.