The L Absorption Limits of Tungsten: Photometric Measurements

In a previous paper both the absorption and emission spectra of tungsten were photographed simultaneously on the same plate. It has since seemed advisable to make a photometric analysis of the original plates showing the L absorption bands. The results give for ${\mathrm{L}}_1$, 1.2117A, and for ${\mathrm{L}}_2$, 1.0708A, as compared with the former eye measurements of 1.2122A and 1.0716A, though the last are regarded by the author as more reliable. The mean variation in the measurements is less than.0002A. ${\mathrm{L}}_1$ is clearly between ${\beta }_5$ and ${\beta }_{10}$ and ${\mathrm{L}}_2$ between ${\gamma }_6$ and ${\gamma }_2$, indeed between ${\gamma }_6$ and a new line, 1.0699A.