Hank Tennenbaum Story about Al Jolson

My father played rhythm bones with Al Jolson on the street in DC in front of the burlesque houses for the lines going in. Pennies, nickels, and dimes. They rarely saw quarters. Jolson sang and whistled, and my father played rhythm bones and did sand dancing. Jolson taught my father his style of whistling and my father tried to teach me but neither of us was any good at it. Hank