Part of the Treatise on rhythm, colour and ornithology written in French by Olivier Messiaen, this volume is the first of the 7 tomes. This volume focuses on time, rhythms, Greek metrics, Hindu Rhythms and an analysis of 39 choirs of 'Spring' by Claude Le Jeune.

This treatise depicts the full theory behind Messiaens compositions and how he composed the music, including his conception of rhythms, his incorporation of birdsong and his relation to sound and colours.

While most of the composers struggle to explain their composition, Messiaen has managed to write a Treatise in 7 volumes to explain all the important aspects of his work.

Olivier Messiaen (1908-1992) was a French organist and composer passionate about Ornithology and one of the most important composer of his century. Inspired by Japanese music, he had a very special way of composing and his work can be identified by its complexity, its diatonic aspect, its harmony with limited transposition, its colour and its additive rhythms. He composed many works related to ornithology and birdsong, including the 'Bird Catalogue' in 7 volumes.