Anode Ray Tube

Physics

Accession Number: 2009.ph.30

Description:

A long cylindrical glass bulb mounted vertically on top of turned wooden base. The top and bottom of bulb have disc-shaped electrodes. In the middle of the bulb, on the same side and 5 cm apart, are two projections. The top one 3 cm long, the bottom one 6 cm, each containing an electrode. The top projection is attached to a metal ring inside the bulb. Likely contains rarefied hydrogen.

Alternative Name: Canal Ray Tube

Primary Materials: Metal, Glass, Wood

Markings:

Old inventory number = phy67. A label under the lower projection reads “Rich. Muller; 299; Braunschweig”.

Dimensions (cm):

Height = 41.5, Base Diameter = 14; Bulb: Height = 25, Diameter = 4

Function:

Cathode rays travel from the porous disc to the bottom of the tube, while anode rays (“canal rays”) travel from the bottom through the disc. Experiments with “canal rays” helped establish that protons are substantially more massive than electrons.

Condition:

Associated Instruments:

Manufacturer: Rich. Muller, Braunschweig

Date of Manufacture:

Provenance:

Historical Notes: