Understanding Electric Discharges in Gas Tubes: Experiments and Atomic Structure

[manjuvenamma]

Can some one kindly explain or give a reference link that explains why it happens what it happens in electric discharges through gases like William Crookes expermient of 1870s and JJ Thomsons experiments with cathode rays? Covering also such important aspects such as what would have happened if we did not remove air/gas in the tube? Basically, I want to know how our present knowledge of atomic structure explains the experiments and its results?

 

[mikelepore]

http://en.wikipedia.org/wiki/Thermionic_emission
http://en.wikipedia.org/wiki/Cathode_ray_tube