United States. Surgeon-General's Office, American Roentgen Ray Society · New York : Middleditch · leaf 31
hardson and others that electrons wereemitted by hot metals. The simplest application of this principle to Roent-gen ray development has been worked out by Dr. W. D.Coolidge in the Research Laboratory of the General Elec-tric Company at Schenectady. In this tube, the cathodeis a spiral filament of… … Fig. 5. Coolidge cathode construction- 2 3
