We finally reach the discovery of electrons. The path starts with experiments on electricity in small vacuum vessels and vacuum pumps, improved by Heinrich Geissler, further improved by William Crookes, and then proving that their mysterious cathode rays were matter, not light, responding to electric and magnetic fields and possessing a mass, as J.J. Thomson showed. Robert Millikan determined the actual mass of the electron. We hear about Thomas Edison's strange electrical effect, and Heinrich Hertz's photoelectric effect. Finally we end with a variety of possible models attempting to explain the structure of atoms.

Support the show

• Support my podcast at https://www.patreon.com/thehistoryofchemistry
• Tell me how your life relates to chemistry! E-mail me at [email protected]
• Get my book, O Mg! How Chemistry Came to Be, from World Scientific Publishing, https://www.worldscientific.com/worldscibooks/10.1142/12670#t=aboutBook