The author wishes to express his gratitude to Professor Ashley Horace Thorndike of Columbia University for his generous and invaluable criticism of this essay in its first and final forms. He also wishes to thank Professor Emery Neff and Dr. Henry Wells, of Columbia University, for their ready encouragement and criticism of this project in its various stages of development. He furthermore owes thanks to the Trustees of Columbia University for the award of a "Cutting Fellowship" which provided a year of study and travel. Most particularly, he wishes to express his gratitude to Professor Henry K. Dick and to Dr. Charles W. Everett of Columbia College for their warm interest and generous criticism of this essay from its beginning to its completion.
He wishes also formally to thank Dr. Samuel Monk of Princeton University, Mr. George Hibbitt of Columbia College and Mr. Francis Steegmuller for aid in bibliographical search; and Miss Suzanne Ziegler for friendly criticism of the text of this volume.
He is furthermore indebted to the courtesy of the librarians of the Morgan Library, New York City, for the privilege of examining the manuscripts of Modern Painters and Stones of Venice; and to Sotheby and Co., London, for their kindness in permitting the perusal of several volumes of Ruskin's notebooks before their sale in July 1930.