As a small boy, Gershwin had few encounters with music. Years later, he remembered that heating a violinist at P.S. 25 play Humoresque gave him ""a flashing revelation of beauty."" At 12, he began piano lessons in the neighborhood with a ""Miss Green"": such are the beginnings of genius. This book is most interesting in describing a genius-at-work: using musical quotation from black and Jewish sources as well as ragtime; working from his own notebooks; buying a book about concertos ""to help him figure out how to write one."" Nadia Boulanger told Gershwin that ""there was nothing she could teach him."" And when he asked Ravel to teach him orchestration, Ravel is said to have replied: ""Why be a second-rate Ravel when you are already a firstrate Gershwin?"" Gershwin's unique gifts are made apparent here, though the mention of a huge number of songs, Broadway shows, movies, and famous names of the period may be off-putting for those not familiar with them. Most helpful as accompaniment to re-cordings of Gershwin's music.