It is not clear when the essentially formalist notion of inner light became a commonplace in the criticism of Venetian painting of the sixteenth century, but it was certainly a major concern of the Bavarian painter Max Doerner, whose handbook The Materials of the Artist and Their use in Painting, with notes on the Techniques of the Old Masters (1921), had been published in an English translation in New York in 1934 and came to be much used in the circle of the abstract expressionists. Although Rothko has the reputation of being a poor technician, it is striking that he adopted a number of the thoroughly traditional materials and techniques discussed in Doerner's book, notably the grinding of his own pigments and the use of a variety of egg tempera. In addition to Doerner's particular interest in traditional methods, as implied in his title, he felt able to recommend some of the new synthetic materials, such as the titanium white and the coal tar 'lithol fast scarlet,' which were later used so disastrously by Rothko in his Harvard murals. On the other hand, Rothko showed none of Doerner's concern for the careful construction of stretchers, and he adopted the late medieval technique of interposing an isolating egg-white glaze between layers of pigments or vanish, which Doerner had specifically discouraged since egg white becomes very brittle with time and turns brown. Yet these examples too suggest that Rothko was quite familiar with Doerner's book," wrote John Gage in his essay.