and physical, discovered the thallium using spectral analysis, but it
was his work on cold cathode tubes, these tubes Crookes who made
to the work of Geissler
(production vacuum) Crookes was able to get a high vacuum on its pipes,
applied DC voltage of about 20-30 kv to anode and observed a beam of
light greenish, cathodes rays. In 1870 states that
are cathodes rays 'particles' with a negative electric charge.
Produced the first electronic tube that allowed
Thomson of the discovery.
Prize for Chemistry in 1907.