Classical Harmonica: Before Larry Adler there was no such thing as a classical mouth organ player. He hit his stride in the 1930s, playing with George Gershwin and many of the great performers of the day. Composers such as Ralph Vaughan Williams, Darius Milhaud and Manuel de Falla wrote music for him. Thispast weekend, Adler—who''s in his 80s—gave a series of four concerts celebrating Gershwin with his hometown orchestra, the Baltimore Symphony. In the first of a two-part interview, Martin talks with Adler about how he got kicked out of the Peabody Conservatory, toured with the harmonica as a teen,and established himself as a classical musician.