Bidspirit auction | 2 middle C (256) tuning

2 middle C (256) tuning forks mounted on spruce (?) resonator boxes, circa 1870-1900, 11 1/2” X 5” X 12” each - 2 middle C (256) tuning forks mounted on spruce (?) resonator boxes, circa 1870-1900, 11 1/2” X 5” X 12” each,