Equivalent widths of 82 Cr I lines, 70 Fe 1 lines, and 74 Ti I lines are measured in the spectra of four sunspots of average area 55 millionths of the visible hemisphere of the sun. Separate curves of growth for Cr I, Fe ...

The equivalent widths of the g and K lines are measured at the pole and at the equator of the Sun during a period of minimum solar activity. The difference of temperature between pole and equator is evaluated by Woolley's ...