I finally got to see San Diego I Love You a 1944 movie
where Buster Keaton is a bus driver. After ten years back
and forth on the same route, he decides to take the bus on
a detour. There's a great scene of the bus driving along
the moonlit beach, while a passenger in the back plays
violin. Also, a gag I'm sure Buster wrote involving a
barbershop specializing in black eyes.