I am grateful to the countless individuals and institutions who have aided in the preparation of this book. I am particularly indebted to the staff of The New-York Historical Society, to Carolyn Scoon, Wilmer Leech, and Edward Santrucek for cooperation over many years, a consideration that has continually nourished my research in the nineteenth century. Jane des Grange and Anne Klein of the Suffolk Museum and Carriage House at Stony Brook, Long Island, were most generous in giving me access to Mount material. E. Hyde Cox and Caroline Benham of the Cape Ann Historical Association, Gloucester, Massachusetts, were helpful with photographs of Lane's work. Wendy Goodel of the Museum of Fine Arts, Boston, made photographs from the collections available with the greatest good will.
I am indebted to the following publications for permitting me to adapt these articles: Art News, "Copley: Eye and Idea," September, 1965; Bulletin of the Rhode Island School of Design, Museum Notes, "Thomas Cole", December, 1965; College Art Journal, "Asher B. Durand and European Art", Summer 1962.
The ideas presented in Chapter 5, on luminism, were first offered in a lecture at The Metropolitan Museum of Art on "Light and Space in Nineteenth-Century American Landscape Painting," in April, 1965.
I take this opportunity to thank the Trustees of Barnard College, Henry Boorse, Dean of the Faculty, and the Department of Art History for granting me the leave from my teaching duties that made it possible to complete this volume. My gratitude to my mentors and colleagues Marion Lawrence and Julius Held extends far beyond the few years during which the book was in preparation. To Benjamin Rowland, Jr., of Harvard, my thanks for initial encouragement of my work in the American field. I would like also