Signedstamped in white on bulb: 10 M.A. / COOLIDGE / (VICTOR logo) / - TUBE - / MADE IN U.S.A. / 80491
Inscribedstamped in white on tube: U.S. PATENTS - 1,082,933 - 1,101,063 / 1,140,134 - 1,140,135 - 1,140,136 / 1,162,339 - 1,162,340 - 1,162,341 / 1,203,495 - 1,211,091 - 1,268,647 / 1,310,061 - 1,326,029 - 1,498,903 / 1,502,907 - 1,558,436 - 1,688,32# / PATENTS PENDING / THIS TUBE IS NOT LICESNSED (illegible) / RE-EXAUSTED OR REPAIRED NOR / THE METAL THEREIN CONTAINED / LICENSED TO BE USED EXCEPT IN / THIS PARTICULAR TUBE. / GENERAL ELECTRIC X-RAY CORP. / CHICAGO, ILL., U.S.A.
FunctionThis coolidge tube produces electrons by the heating of a cathode filament. These electrons are accelerated by a high voltage and hit the angled anode to produce the x-rays. Due to the large amounts of generated heat, this unit originally included radiator fins as a cooling mechanism, which allowed for a relatively small bulb size. It could also work without a rectifier as the anode was kept cold enough not to emit electrons for an inverse current.
This one was probably used for radiography.
ProvenanceFrom the Harvard Medical School.