A music historian with a fine interpretive ear for both music and language examines the collaboration of George and Ira Gershwin- -in what is not a biography but rather a nontechnical study of how the Gershwins' music, lyrics, and sense of drama are interrelated. With the help of in-depth interviews with Ira Gershwin, Rosenberg (Music Theater Program/NYU; The Brothers Gershwin, 1989- -not reviewed; coauthor, The Music Makers, 1978) traces the creative development of the major Gershwin songs and shows. After a short discussion of the brothers' upbringing and exceedingly different temperaments (``We never had much in common as kids,'' Ira recalled. ``I was always home reading...[George] would get into street fights and come home with black eyes''), she launches into a wide-ranging discussion of Rhapsody in Blue and ``The Man I Love,'' the breakthrough song in which the Gershwins first discovered their ``ability to make a song intrinsically dramatic.'' Next comes an examination of Lady, Be Good; here, Rosenberg cites one major reason why the brothers---especially at first---were so different from other collaborators: In the early days of musical comedy, stars were chosen and songs composed before the ``book'' (i.e., plotline, dialogue) was written, a separatist approach very much against the symbiotic Gershwin instinct. Other chapters study such shows as Oh, Kay! and Girl Crazy and explain such pivotal details as how George's ``blue'' notes affect the meaning of Ira's words. The chapter on Porgy and Bess is especially interesting. ``Above all,'' writes Rosenberg, ``Porgy and Bess is suffused with two [Gershwin] characteristics....The first is a depiction of deep loneliness....The second...is an appreciation of a diverse national character.'' Though at times too detailed for the general reader, Rosenberg's straightforward prose is a pleasure. Intriguing and insightful, casting new light on the Gershwin genius. (Black-and-white photographs; score samples.)
