Crookes Tube

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Crookes Tube The Crookes tube is an experimental cathode-ray tube designed for studying electrical discharges at low pressures. The device was invented in 1875 by the British physicist William Crookes. Crooks was one of the first scientists to systematically study propagation of the electric discharge in glass tubes filled with low density gas. The tube is shaped like a large pear, with metal plates soldered on both sides. Structurally, the tube is a glass cylinder with two electrodes soldered into it: an anode and a cathode. The tube is attached to a vacuum pump, which is used to pump out the air. The phosphorescent compound was used to coat the tube surface opposite the cathode. Once the electrodes were exposed to high voltage, the glass produced a bright glow. Crookes analyzed these observations only to conclude that the cathode produced a flux of rays that were later called cathode rays. If any impediment is placed on the path of cathode rays, the phosphorescent surface will contain a shadow of the object. This observation served as a basis for the following conclusion: the cathode rays, like any other radiation, propagate in a linear manner. For Crookes this device always remained to be a simple source of extraordinary rays, which were propagated by the negatively charged electrode (or the cathode). These rays were later called the cathode rays. However, later this tube was used as a prototype of oscilloscope tubes and television tubes.