Since Faraday had called the negative pole or plate the cathode, Goldstein called his radiation, cathode rays. On the wall opposite to the negative cathode, the glass glowed a strange, greenish color.īy 1876 Eugen Goldstein was certain that the glow was being caused by a new kind of radiation that started at the negative plate and radiated across the vacuum until it hit the glass. His superior vacuum pump removed all the air from the tube, and he connected the anode and the cathode to the appropriate ends of a powerful battery.Īt high enough voltages electricity certainly seemed to be able to leap across the vacuum between the oppositely charged plates, but that was not all. His apparatus consisted of a glass tube in which an anode (the positive pole, or plate) was at one end, and the cathode (the negative pole, or plate) was at the other end. Unfortunately his methods of producing an appropriate vacuum were not good enough and he never really succeeded, but a German glass blower - Heinrich Geissler - certainly did. He also got the idea to pass an electrical current (discharge) through a complete vacuum, just to see what happened - if anything. Using this technique, he discovered many things, including new elements, and aroused the interest of his pupil - Michael Faraday (1792 - 1867).įaraday coined many of the terms still used today, including electrolysis, electrolyte, electrodes, anode, anions, cathode and cations. The English chemist Humphrey Davy (1778-1829) had built the world's largest battery (over 250 metallic plates) and pushed the very high currents this battery could generate through all kinds of solutions, compounds and substances in the hope that the high energies involved would pull apart the chemical constituents. In the 1800s electricity was new, exciting and the subject of a lot of study.