's Préludes are 24 pieces for solopiano, divided into two books of 12 preludes each. Unlike some notable collections of preludes from prior times, such as Chopin's Op. 28, or the preludes from Johann Sebastian Bach's Well-Tempered Clavier, Debussy's do not follow a strict pattern of key signatures. Each book was written in a matter of months, at an unusually fast pace for Debussy. Book I was written between December 1909 and February 1910, and Book II between the last months of 1912 and early April 1913.
Pieces
Two of the titles were set in quotation marks by Debussy because they are, in fact, quotations: «Les sons et les parfums tournent dans l'air du soir» is from Charles Baudelaire's poem Harmonie du soir. «Les fées sont d'exquises danseuses» is from J. M. Barrie's book Peter Pan in Kensington Gardens, which Debussy's daughter had received as a gift.
Performance practice
There is no proof that Debussy necessarily intended the preludes to be performed as a cycle, although the musical language throughout each book is so consistent that performers usually do so. An important precedent was set on 3 May 1911 by the pianist Jane Mortier who played the entire first book of preludes at the Salle Pleyel in Paris. The German-English pianist Walter Morse Rummel, a student of Leopold Godowsky, gave the premiere of the entire second book of preludes in 1913 in London. Initially, Debussy and other pianists who gave early performances of the works played them in groups of three or four preludes, which remains a popular approach today. This allows performers to choose preludes with which they have the strongest affinity, or those to which their individual interpretive gifts are most suited. There is a strong tonal relationship between the preludes that suggests that the published order of the preludes is not arbitrary. For example, the first three preludes in the first book revolve around the key of B. In these first three preludes, allusions to the key of B disappear and reappear, yet a strong sense of fluidity and connection between the preludes is still maintained. However, the order of the preludes is not considered imperative, as is the case with Chopin's preludes, for example. Several pianists have performed the set out of order, and at least one recording, by Ivan Ilić, changes the order of the set entirely. The first complete recording of both sets was made in England in 1938 by the South African pianist Adolph Hallis.
The titles
The titles of the preludes are highly significant, both in terms of their descriptive quality and in the way they were placed in the written score. The titles are written at the end of each work, allowing the performer to experience each individual sound world without being influenced by Debussy's titles beforehand. At least one of the titles is poetically vague: the exact meaning of Voiles, the title of the second prelude of the first book, is impossible to determine for certain, since plural nouns do not distinguish genders as the singular forms may do. The title of the fourth prelude «Les sons et les parfums tournent dans l'air du soir» represents a citation from Charles Baudelaire’s poem Harmonie du soir from his volume of poems Les Fleurs du mal.
