December 26, 1930 – Death of Eugen Goldstein, discoverer of the channel beams that led to the discovery of the isotopes

With the support of the German Academy of Sciences, this German physicist carried out numerous experiments on electric discharges in a vacuum that led to the discovery of canal rays, which he first reported to the Berlin Academy in 1886 and continued his research on the same subject until about 1915.

Goldstein observed that when an electric discharge was produced in a tube containing a rarefied gas, using as a negative electrode (cathode) a metal sheet normal to the axis of the tube and provided with small holes, bright rectilinear lines directed towards the part opposite to that occupied by the positive electrode (anode). If the gas contained in the tube was air, the stripes were yellow.

The rectilinear shape suggested rays that spread in a straight line, which is why Goldstein gave them the name of channel rays.

Thanks to the study of the trajectories of such rays, would lead Joseph John Thomson and Francis Aston to the discovery of isotopes in 1913.

If you want to know more about this scientist, click on the following link: Eugen Goldstein