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Direct current measurements have been made of film currents in and emission currents from thin‐film sandwiches consisting of beryllium, thermally formed beryllium oxide, and overlayers of silver, barium or a combination of the two. Silver covered oxide films formed at low temperature yield regular film current characteristics but no electron emission. With high oxidizing temperatures, electron emission can be obtained but the films are subject to frequent breakdown. An intermediate temperature range yields more reproducible film currents and, in many cases, small but steady electron emission. A discontinuous forming process generally precedes the electron emission. Films with barium overlayers break down and heal repeatedly, accompanied by very irregular emission at film voltages considerably below those for silver covered films. Brief exposure of a silver overlayer to barium vapor induces marked changes. Initially, the film current is irregular as it is for barium alone, but as the current increases the characteristic reverts to that for silver without barium. Electron emission is more frequently obtained in this way, though it occurs in the same voltage range as without barium. The film‐current curve shapes indicate that the current is carried mainly by electrons passing over a voltage‐dependent barrier (Schottky effect), but cooling the samples has no effect on these curves, probably because of localized heating. A tentative model is proposed to account for the particular observations reported here. Work function differences, the porosity of the thin silver films, and cracks or grain boundaries in the oxide layer combine to produce highly localized currents, heating, and structural changes consistent with measurements and observed emission patterns.