"She [Mary Cassatt] has infinite talent. I remember the time we started a little magazine called 'Le Jour et La Nuit' together. I was very much interested in processes then, and had made countless experiments [in printing; Degas mainly mono-type - Mary Cassatt mainly etchings].. .You can get extraordinary results with copper; but the trouble is that there are never enough buyers to encourage you to go on with it."