After World War I ended, Eugene Jacques Bullard returned to Paris. He worked as a jazz drummer and nightclub owner, and as the tensions that led to World War II loomed, as an intelligence agent for France.
Research:

John Evelyn's 'Fumifugium'
39:35

SYMHC Classics: Hennig Brand
29:33

Behind the Scenes Minis: Odd Baby Train
28:32