This album demonstrates Dong Qichang's interpretation of the entire spectrum of Song and Yuan styles using a set of contrasting brushstroke methods, which could also be used for depicting actual landscapes. The great theorist and painter took as his point of departure the works of the Yuan master Ni Zan (1306–1374), whose paintings were regarded as calligraphic abstractions of earlier Song styles. In the first two leaves, Dong contrasts—in what he regards as the early and late styles of Ni Zan's art-an "earthen" landscape (round, parallel, "hemp-fiber" brushstrokes) with a "rocky" one (angular, oblique, "folded-ribbon" brushstrokes). In successive leaves, Dong juxtaposes various "earthen" and "rocky" themes in order to evoke different paradigmatic styles of the Northern Song period.