multiplets, do not appear in the solar spectrum. None of the above lines is strong enough to be seen in the spectra of the stars.

IONIZED YTTRIUM

Four of the multiplets attributed to ionized yttrium[334] are satisfactorily identified in the solar spectrum. The wave-lengths and identifications are contained in [Table XVI], p. 83. The arrangement is as in [Table XI].

[TABLE XVI]

SeriesWave-Lenght Int. Attribution Int. Wave-Lenght
*3710.30100Y33710.431
3832.87203833.026
*3774.3350Y33774.473
3878.27413878.334
3818.3710Y13818.487
*3788.693023788.839
3600.7250Y33600.880
3548.9920Y?23549.151
3664.5920Y23664.760
3611.0530Y, Mg?23611.189
3584.5110Y23584.660
3628.7010Y, Mg?23628.847
3601.9120Y13602.060
4309.612014309.792
4235.71604235.894
4199.2833004199.434
4398.0315In zircon [*]14398.178
4358.728Y-Zr04358.879
4422.6010Fe, Y34422.741
5087.4210Y?15087.601
4982.1230004982.319
5320.771--
5205.7110Y05205.897
5119.103005119.292
5289.8120005289.988
5200.418V05200.590

[*] But not Zr.

ZIRCONIUM (40)

The ultimate lines of the zirconium atom[335] are all found in the solar spectrum, far into the ultra-violet.

The bands in the spectra of stars of Class