The effect of extraneous elements on spectral line intensity in the cathode‐layer arc

Data are given for the spectral line intensities of various trace elements in the cathode-layer are when they are incorporated into different bases. The bases considered are alumina, silica, calcium carbonate and phosphate, sodium pyrophosphate, chloride, and carbonate. The effects on the actual line intensities and on the ratios of the line intensities to those of iron as internal standard are considered. Most trace constituents gave their highest line intensities in the alumina base, whilst the more volatile trace constituents like copper, silver, zinc, bismuth, and cadmium tended to be greatly depressed by sodium chloride. Chromium, vanadium, and molybdenum were enhanced by calcium salts and depressed by silica. Constant intensity ratios for cobalt and nickel to iron were obtained in all bases except silica.