Hello !!! Earlier today, I visited a vintage/antique event and I bought this instrument! This is called a psalmodikon, and according to different sources it originates from either Sweden or Denmark. The instrument itself has no bottom panel, and instead is supposed to be played on a table which creates a good sound chamber. Bow is made from horsehair !!
The seller told me this one is from around the 1850s, and that he got it from a couple of old karelian women. He said there were originally some notes for it too, but they have been lost to time.
It sounds much like a cello (o^-')b more photos below














