This bowed zither has movable middle bridges, dividing each string length into two playable segments. The high arching of the soundboard serves the same purpose as the violin’s arched bridge, making the strings individually accessible for tangential bowing. The uprights on the right side of the photo offer string-tension control: by flexing the upright forward or back while bowing, the player can create vibratos and pitch bends in the attached string.
This instrument, originally built many many years ago, seems now to have disappeared — did I give it away or throw it out? — and the only extant audio I could find for it the piece excerpted here, in which sadly the bowed zither plays only a few notes.