Explain the discovery of protons.

(N/A) Electrical discharge carried out in a modified cathode ray tube led to the discovery of particles carrying a positive charge,also known as canal rays.
Characteristics of canal rays:
$(i)$ The positively charged particles depend upon the nature of the gas present in the cathode ray tube. These are simply the positively charged gaseous ions.
$(ii)$ The charge-to-mass ratio of the particles is found to depend on the gas from which they originate.
$(iii)$ Some of the positively charged particles carry a multiple of the fundamental unit of electrical charge.
$(iv)$ The behavior of these particles in a magnetic or electrical field is opposite to that observed for electrons or cathode rays.
The smallest and lightest positive ion was obtained from hydrogen and was called a proton $(H^{+})$.