In his new series, his characters have exciting adventures with every kind of motor-driven machines--motor cycles, automobiles, aeroplanes and submarines. You may readily see what a vast field for adventures Mr. Grayson has chosen. _Now Ready_ BOB STEELE'S MOTOR CYCLE BOB STEELE ON HIGH GEAR BOB STEELE FROM AUTO TO AIRSHIP BOB STEELE AFLOAT IN THE CLOUDS BOB STEELE'S SUBMARINE CRUISE BOB STEELE IN STRANGE WATERS BOB STEELE'S MOTOR BOAT BOB STEELE'S WINNING RACE BOB STEELE'S NEW AËROPLANE BOB STEELE'S LAST FLIGHT