On this day (May 17) in 1937, trumpeter John Birks Gillespie — better known by his nickname, Dizzy — made his first known recording, appearing with the Teddy Hill NBC Orchestra on the Jelly Roll Morton tune “King Porter Stomp” for RCA Records. Dizzy, of course, would go on to pioneer an entirely new movement in jazz: bebop. But it’s fun to hear him at the start of his career — not even 20 years old — laying the groundwork for a style that would change music forever.