Vacuum tube
Vacuum tube, used in an unrecorded experiment on cathode rays from a sphere of aluminium, 1881.
Vacuum tube used in an unrecorded experiment on cathode rays from a sphere of aluminium, on stand, 1881
Vacuum tube, used in an unrecorded experiment on cathode rays from a sphere of aluminium, 1881.
Stand, black, for vacuum tube used in an unrecorded experiment on cathode rays from a sphere of aluminium, 1881.