series, which may be regarded as corresponding to the binding of the
th electron in the normal state of the calcium atom.
Fig. 4.
These facts are shown in [figure 4] which gives a survey of the stationary states corresponding to the arc spectra of sodium and potassium. As in figures [2] and [3] of the sodium spectrum, we have disregarded the complexity of the spectral terms, and the numbers characterizing the stationary states are simply the quantum numbers
and
