Accession No

1955


Brief Description

glass discharge tube with shell target, 1875–1925


Origin


Maker


Class

physics


Earliest Date

1875


Latest Date

1925


Inscription Date


Material

glass; metal (aluminium?); wax (sealing wax); shell


Dimensions

height 360mm; breadth 140mm; depth 90mm


Special Collection

Cavendish collection


Provenance

Transferred from the Cavendish Laboratory, University of Cambridge, in 1974.


Inscription


Description Notes

Glass discharge tube with curved support tube and terminals at top (aluminium disc) and one side. Piece of shell is supported in main reservoir as the target, so that it is illuminated when a current is passed through the tube. Two side arms.

Condition good; complete.


References


Events

Description
Glass has been prized for centuries for its transparency and moldability. It’s these qualities that make it one of the most important materials in the history of physics. The Whipple cares for a large collection of glassware from the University of Cambridge’s Cavendish Laboratory of Experimental Physics.

Most of it dates from the 1880s to the 1930s, when Cavendish Professor J.J. Thomson and his students were studying the mysterious glows and rays that can be seen through the glass when electricity is run through a gas in a partial vacuum. These studies led to Thomson’s discovery that cathode rays were made up of sub-atomic negatively charged particles in 1897. He named them corpuscles: we know them as electrons.

The Cavendish Laboratory’s technical team included gifted glassblowers. They created and repaired the intricate vessels to order: whatever the researcher needed for his or her experiments. Many of the technicians joined the Laboratory as young boys and remained there throughout their careers. This meant there was an unbroken continuity of craft and technical knowledge across the Laboratory’s first six decades.

Physicists' experiments with discharge tubes stretched the glass-blower's art: each new experiment might require a new or adapted form, like the swan's neck here. As the fragile tubes were under vacuum, they could implode dangerously if shattered.




10/07/2025
Created by: Hannah Price on 10/07/2025


FM:40473

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