In 1955 Boulez revised the order of these movements and interpolated three newly composed ones . The original, six-movement form lacked the two "Bel Édifice" settings and the third "commentaire" on "Bourreaux de solitude". In addition, the movements were grouped in two closed cycles: first the three "Artisanat furieux" movements, then the three "Bourreaux de solitude" ones, otherwise in the order of the final score. The first movement, though fundamentally the same composition, was originally scored as a duet for vibraphone and guitar—the flute and viola were added only in the revision—and numerous less significant alterations were made to playing techniques and notation in the other movements .