Accordion with foot pedals used to pump the bellows
Video with "Harmonia Pedalowa" - Polish 3 row accordion with foot pedals used to pump the bellows. Harmonia - general term for the accordion used in Poland from the end of the l9th century. In order to facilitate playing, in some regions (e.g. Kurpie) a pedal pump is used for pumping air through a metal pipe to the bellows of the instrument, which is then called harmonia pedalowa or simply pedalówka (treadle).
Harmonia pedalowa cz.5 - YouTube