Last Thursday, the modestly clad figures in marble that adorn Symphony Hall's walls looked down upon a flood of giggling women. From eleven-year-old girl scouts to Radcliffe and Simmons College bobby-soxers, the girls had turned out in strength to see conductor-soloist Leonard Bernstein lead the Boston Symphony Orchestra in a rehearsal.

Picking his way through the orchestra to the podium, Bernstein clapped his hands to silence the applause. He removed his sport coat, revealing a white turtle-necked sweater, and there were a few whistles from the balcony. Smiling in a melancholy way, Bernstein announced, "The first number we shall rehearse, (Der Wein, by Albert Berg) is a group of sonnets about wine. In it, wine sings--in German, of course--as the first person: I comfort you, I fill your stomach, and so on." He then introduced the Wine, a black-haired soprano named Patricia Neway, who had poured herself into a black turtle-neck dress for the occasion.

Eschewing a baton and beating time heavily with his foot, Bernstein lead the orchestra and Miss Neway through the wandering atonalities of Der Wein. At one point he clapped his hands to stop the Orchestra and called Miss Neway to the podium for a discussion. After mulling over the score for a minute or two, Bernstein turned and told the audience, "If this passage has been unintelligible to you, I can tell you that it was the preceding passage--backwards. We shall play it for you again, just to give you another chance."

After the Orchestra had gone through Der Wein to the conductor's satisfaction, everyone took fifteen minutes out for a cigarette. Then Bernstein returned to rehearse parts of Sibelius' Fifth Symphony. This time Bernstein tailored his gestures to the varied moods of the music. During strident passages he reached out toward the orchestra as if to grab handfuls of sound; during the lighter moments he bounced up and down and flapped his arms like a happy bird.

As the ten o'clock musician's union curfew approached, it looked as if the audience might never learn how Bernstein plays and conducts Mozart's Concerto in E-flat major at the same time. Twenty minutes before the deadline, however, stage-hands wheeled a piano to the front of the stage, the conductor mounted the piano stool, and the Concerto began. Bernstein conducted, then played a few measures, then waved one hand while playing with the other, all the while chatting with members of the Orchestra. When both hands were occupied, he conducted with quick jerks of his head. He made only one mistake--a misplaced trill--which he passed off with a "pardon me" to the audience.

At the rehearsal's end the audience cheered, the orchestra bravoed, and the members of the string section politely tapped their instruments with their bows. Mopping his brow, smiling, and smoothing out a few wrinkles in his turtle-necked sweater, Bernstein acknowledged the kudos and turned to leave. As the audience filed out through the doors, two little girls clambered onto the stage waving autograph books.