A so-called 'mechanical'--the postcard has a little paper tab which when pulled makes the right arm move back and forth as if the man (woman ?) here were playing.
One enjoys the sound of the accordion, musette, concertina, bandoneon, squeeze boxes of all sorts. Some version of the concertina known in virtually every culture on earth. Planet Squeezebox: the name of a marvelous 4-CD set from the 90s of world music spotlighting accordions and the like. Pure joy. Fine fun. Does the name *Gus Viseur* light up any switchboards?