Frederick Sommer taught at the Institute of Design in 1957– 1958, when Harry Callahan was on sabbatical in France. With his background in Surrealism and his acquaintance with Max Ernst, whom he had met in the 1940s in Arizona, Sommer brought something new to the Institute’s curriculum. While in Chicago, Sommer experimented by making his own negatives without the use of a camera. He painted compositions on fourby- five inch sheets of cellophane, which he then enlarged when printing on light-sensitive paper. Paracelsus, which the artist considered the best of his cliché verre work, oscillates between its appearance as a flayed torso and an abstract study of texture and tone.