Cathode Ray Tube

Physics

Accession Number: 2009.ph.205

Description:

A glass sphere, about 8.5cm in diameter, with four short glass projections, each holding an electrode. A glass bulb is mounted with curved glass stem from the bottom electrode projection to the wooden base. Slight burn marks directly across from the cathode.

Alternative Name:

Crookes Cathode Ray Tubes; High Vacuum Tube of High/Low Pair

Primary Materials: Wood, Metal, Glass

Markings: Old inventory number = phy63.

Dimensions (cm):

Height = 23 cm, Length = 11 cm, Width = 8 cm

Function:

Condition:

Slight burn marks directly across from the cathode.

Associated Instruments: Crookes Tubes (Various)

Manufacturer:

Likely built by Richard Uri-Muller (Braunschweig).

Date of Manufacture:

Provenance: Collection of Dr. Martin Lee.

Historical Notes:

Typically sold in pairs, one with a higher vacuum (lower pressure) than the other. The low vacuum tube would result in rays moving up and away from the cathode, towards an active anode, while the high-vacuum companion would show rays moving straight, directly across the cathode. Judging by the marks on the glass, this tube was the high vacuum (low pressure) tube.