Source:  Electron    Tag:  cathode ray discharge tube experiment
In 1875,William Crookes carried out experiments with discharge of electricity electron through gases. The glass tube used to study the discharge of gases at low pressures is called discharge tube. It is a glass tube of 50 cm long and 4 cm in diameter as shown in the fig
When a high voltage source was connected between the two electrodes,one plate was positively charged and the other plate was negatively charged.i.e one is anode and the other is cathode.when tube is evacuated , abeam of current passed from cathode to anode in a straight line. This beam was named "cathode ray"
surprised to this result and started working to find out what these cathode rays were. It was sir J.J.Thomson who provided the correct answer in 1897.He showed that cathode rays could be deflected in magnetic and electric fields.In an electric field, they were attracted towards the positive plate.so these rays must be composed of negatively charged particles. They could not be waves because light waves cannot be deflected by electric and magnetic fields.
The name ELECTRON was given by Johnson stoney to this negatively charged particle. Thomson was also able to measure the mass-to-charge ratio of the cathode ray particle(electron).For his work,Thomson won the Noble prize in physics in 1906.