J.J. Thompson conducted his cathode ray experiment in 1897. Thompson had a long-lasting interest in the atomic structure, and this experiment resulted in the discovery of the electron.
J.J. Thompson was a British physicist born in 1856 who received the Nobel Prize for Physics in 1906. His research on negatively charged particles was essential for understanding the atom's structure, which led to further experiments by Ernest Rutherford and Niels Bohr. Thompson was the first physicist to develop the idea for the structure of the atom, which was then believed to be the smallest possible particle in the Universe, and was apparently indivisible.