Before Cage embarked on his great lifelong experiment with indeterminancy in music--a historic exploration in which he sought to create music through chance events rather than predetermining it through artistry and/or craft--he had already gained a reputation as a radical because of his creation and use of the prepared piano. This is a piano that has been set up before the concert with various devices attached to specific strings: nuts, bolts, wires, and the like that might dampen or alter the pitch or tone produced, which is unlikely to be the one normally associated with each key. The result is radical in effect but seems to have emerged from a practical problem: Cage had been engaged to provide music for modern dance and wanted to make percussion and rhythmic effects without engaging lots of percussion players and instruments. In effect, then, a "prepared piano" is really just a box of percussion sounds. These sounds are not chancy at all: In his prepared piano pieces Cage meticulously prescribes just what piece of hardware goes where in the piano. Now, the key question: How does all this sound? Actually, the music is usually beguilingly exotic and pleasant to listen to. Daughters of the Lonesome Isle is a ten-minute, 1945 composition written for dancer Jean Erdman, and is one of the best and most famous of this entire genre of Cage's music. His efforts reached their compositional zenith a few years later with the marvelous Sonatas and Interludes for Prepared Piano). ~ Joseph Stevenson, All Music Guide
