On the Mercury Line 2270 A (1S - 2p1)

Excitation of the mercury line $\lambda 2270$.—In a previous experiment by Hansen, Takamine and Werner, the line $\lambda 2270 (1S-2\mathrm{}{p}_1)$ was found to be excited either in a condensed discharge or in a strong magnetic field. By using the method employed by Metcalfe and Venkatesachar for the study of the absorption of mercury lines, it was found that the glow in the branched arc of a special kind of mercury lamp emits this line with considerable intensity. Under best circumstances, its intensity was stronger than the arc line $2302 (2\mathrm{}{p}_2-9\mathrm{}{d}_2)$, but fainter than $2323 (2\mathrm{}{p}_2-8\mathrm{}{d}_2)$.