The First Sonatina
The materials of Book 1, and the "Epilogo," all related and highly original compositions, and written in the new style first explored in Elegien (BV 249), were later revised and combined with a new introduction and short linking passages presenting the thematic roots of the pieces and gluing them together into a single entity. The new piece, resembling a set of variations without a theme, Busoni entitled Sonatina (BV 257). This more advanced and forward-looking composition was the first of what would eventually be six "sonatinas" containing some of the most unique and original piano music of the early 20th century.
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