First published as Nihyaku Toka in 1906, The 210th Day is published here for the first time in English. Focusing on two strongly contrasting characters, Kei and Roku, as they attempt to climb the rumbling Mount Aso as it threatens to erupt, it is a celebration of personal experience and subjective reaction to an event in the author's life. During their progress up the mountain—where they encounter a storm on the 210th day (the lunar calendar day traditionally associated with typhoons)—and during a stopover at an inn along the way, Roku, the main protagonist, banters with Kei about his background, behavior and his reaction to the things they see. Kei surprises his easy–going friend by advocating a radical social agenda.

Written almost entirely in the form of an extended dialogue, carried over several episodes, the book reveals Soseki's gift for the striking image and his vivid imagination, as well as his talent for combining Eastern and Western genres—the Western auto–biography and the Japanese traditional literary diary—into a work with a unified theme and atmosphere.

In his Introduction to the book, Dr Marvin Marcus, Associate Professor of Japanese Language and Literature at Washington University, provides insight into Soseki's life and work.