another scarce early LP by John Cage, Sonatas and Interludes (1946-48) is considered Cage's first mature composition. The idea of a prepared piano filled with nuts, bolts, screws, rubber mutes and weather-stripping comes as much from Cowell's tinkering 15 years earlier (Aeolian Harp, for instance) as it does from Cage's engagement with percussion ensembles beginning in 1937. Indeed, it was the practical limitations of the stage at the Cornish School that forced Cage, an accomplished pianist, to consider the piano as his personal percussion ensemble (Bacchanale). And while many writers acknowledge the possible portrayal of the eight "permanent emotions" of Indian aesthetics (the erotic, heroic, odious, anger, mirth, fear, sorrow and the wondrous -- and their common tendency towards tranquillity), there is nothing in the score to suggest such a direct reference--although in a review of the 1949 Carnegie Hall performance, Cage says that the emphasis on ten-bar phrases in the last four sonatas represents tranquillity.