In July 1946 Clark was appointed Slade Professor of Fine Art at Oxford for a three-year term. The post required him to give eight public lectures each year on the "History, Theory, and Practice of the Fine Arts". The first holder of the professorship had been Ruskin; Clark took as his first subject Ruskin's tenure of the post. James Stourton, Clark's authorised biographer, judges the appointment to be the most rewarding his subject ever held, and notes how, during this period Clark established himself as Britain's most sought-after lecturer, and wrote two of his finest books, "Landscape into Art" (1947) and "Piero della Francesca" (1951). By this time Clark no longer hankered after a career in pure scholarship, but saw his role as sharing his knowledge and experience with the wide public.