In 1894 Nikola Tesla noticed damaged film in his lab that seemed to be associated with Crookes tube experiments and began investigating this " radiant energy of " invisible " kinds ".
42.
Developed from the earlier Geissler tube, the Crookes tube consists of a partially evacuated glass bulb of various shapes, with two metal electrodes, the cathode and the anode, one at either end.
43.
The technology of manipulating electron beams pioneered in Crookes tubes was applied practically in the design of vacuum tubes, and particularly in the invention of the cathode ray tube by Ferdinand Braun in 1897.
44.
They were accelerated to a high velocity by the electric field between the electrodes, both because they did not lose energy to collisions, and also because Crookes tubes were operated at a higher voltage.
45.
But the Crookes tube, as it came to be known, produced little light because the vacuum in it was too good and thus lacked the trace amounts of gas that are needed for electrically stimulated luminescence.
46.
He built a Crookes tube ( later called a " Lenard tube " ) with a " window " in the end made of thin aluminum, facing the cathode so the cathode rays would strike it.
47.
There was at the time not a single Crookes tube in Chile, which is why they began to experiment with light bulbs having a vacuum analogous to these tubes, but lacked the adequate electrodes for the anode.
48.
We knew that the vacuum of an incandescent lamp of good quality is comparable to that of the Hittorf or Crookes tubes, and that, furthermore, the degree of vacuum in such lamps improves significantly after illuminating 100 or more hours.
49.
However, in Thomson's Crookes tube the density of residual atoms was so low that the space charge from the electrons and ions was insufficient to electrically screen the externally applied electric field, which permitted Thomson to successfully observe electrical deflection.
50.
However, bearing in mind at the same time certain qualities of incandescent light bulbs, generally known as Edisons, we considered that for the generation of the R�ntgen rays one could do without the Crookes tubes or others of the same type.
