Which Gas Was Used in J.J. Thomson's Cathode Ray Experiment?

[satrohraj]

Which gas is used in cathode ray experiment by J.J. Thomson & Sir William?

The voltage they used was about: 15k-20k V
The pressure they used: < 0.1mm of Hg
The gas they used: ?

 

[Astronuc]

Apparently different gases were tried in cathode ray tubes at the time.

However based on the fact that Thompson used an evacuated tube (0.1 mmHg vs 1 atmosphere or 760 mmHg), the I would expect the gas was air.

http://www.aip.org/history/electron/jj1897.htm

 

[f3nr15]

Apparently different gases were tried in cathode ray tubes at the time.

However based on the fact that Thompson used an evacuated tube (0.1 mmHg vs 1 atmosphere or 760 mmHg), the I would expect the gas was air.

http://www.aip.org/history/electron/jj1897.htm

What a coincidence, I'm on that site too searching for a brief outline of the debate on whether cathode rays are waves or particles (both are correct) and the properties which they exhibit categorized them as either waves or particles.