THE ULTRAVIOLET SOLAR SPECTRUM, λλ 2935-3060.

Solar spectrograms, obtained with a 21-foot concave grating, show better detail below X 3100 than has been reported previously. New measurements of wave length and visual estimates of intensity have been made for 665 lines, XX 2935-3060. Solar standards of wave length near X 4500 were observed in the second order for fixing the scale in the overlapping third order. Final measurements were made in the second-order ultraviolet. The new intensities are consistent with those found in the region of greater wave lengths; many of them differ widely from the early values. From a thorough study of laboratory data, identifications have been found for three-fourths of the tabulated lines. The lower E.P. is given for every classified line. Additional measurements (500 lines, XX 3060-3150), not presented in detail, show that differences be- tween our interpretation of solar spectrograms and that made by Jewell from Rowland's plates occur even where it is easy to obtain excellent spectrograms. The text is accompanied by tables and reproductions of spectra