Quote from Louis Armstrong in Richard Hadlock's "Jazz Masters of the Twenties," pages 16-17: While he was playing with Fletcher Henderson at Roseland in 1924 "Victor Lopez came in there as guest one time. B. A. Rolfe was with him, and he would play a tune called 'Shadowland' an octave higher than it was written. I observed that, and it inspired me to make 'When You're Smiling.'" Ironically, in the same quote Armstrong criticized trumpeters who thinned out their tone just to play high, which is what I hear Rolfe (or whoever) doing on "Roses Remind Me of You." On the 1929 "When You're Smiling," Armstrong plays with the same full tone in his normal register and in the solo he takes at the end an octave higher than the rest of the record.