This bookis intended to be of assistance to the physicist or engineer concerned with designing and building electron devices such as high-vacuum transmitter- or amplifier tubes, gas- or vapor-filled rectifiers, thyratrons, X-ray or luminescent tubes, glow or incandescent lamps, Geiger- or ionization counters, vacuum photo- cells, photoconductive cells, selenium-, germanium- or silicon rectifiers or trans- istors. For this purpose, extensive information is required concerning the compo- sition, behavior and handling of materials as well as a thorough knowledge of high-vacuum technique...