Dr. Eugen Goldstein was a German physicist who was an early researcher in the area of discharge tubes and atoms, and has also been credited with the discovery of the proton. Goldstein worked at both the Berlin Observatory and the Potsdam Observatory during his career. While conducting research using Crookes tubes, Dr. Goldstein discovered that the tubes emitted light and that magnetic fields had an influence on that light. He eventually named these light rays Cathode rays. This research was the foundation of the eventual discovery of anode rays.
After the discovery of the cathode rays, Dr. Goldstein went on to do further research in this area. Because of the discovery of the nucleus by another scientist, Goldstein was able to differentiate between that part of the atom during the discharge experiments and located the positively charged particles. These were named "protons." His experiments with the discharge tubes caused him to observe the passage of electricity through the gases at both high and low pressure. While conducting the experiment with the low pressure gases, he discovered the anode rays.
During the discharge tube experiments, Goldstein noticed another phenomenon. When the perforated cathode is used, some radiation and particles appear behind the cathode ray itself. The radiation particles behind the cathode ray emanate from the anode. Like the proton, these particles, or rays, carry a positive charge. Because these positively charged radiation particles were coming directly from the anode, Dr. Goldstein named them "anode rays."
Because anode rays had a set of distinctive characteristics, which means they performed differently from the cathode rays, Dr. Goldstein was able to observe some identifiable features of this new type of ray. Anode rays in the experiment were traveling in a straight line and were made of material particles. These particles contained a positive charge and were made of gases already present in the current experiment. When these particle masses are thousands of times larger than the electrons in the atom, they become protons.