The brief Fantasia gregoriana, op.65, is based on the Gregorian Easter Hallelujah. Like a mosaic, the individual heterogenic episodes, lyrical, dance-like, hymnal and dramatic in turn, are combined through the permanent presence of the theme into a unified whole. The Gregorian Hallelujah is present as a type of mode in every bar of the work. The subdued introduction, characterised by the tritonically transposed structure of the original material, is followed by a sharply accentuated presentation...