An attempt was made to excite the $4f$ electron spectrum of Ag II in the Schüler tube with helium. Failure is discussed assuming the excitation process Ag normal atom+${\mathrm{He}}^{+}$. Some little extension was made to the lower spectrum. The Schüler tube was also used to extend the $4d^{8}6s$ and $5d$ configurations of Pd II. About forty terms were added. A complete list of lines arising from high levels is given.

• Received 9 June 1930

DOI:https://doi.org/10.1103/PhysRev.36.173