Agnes Mary Clerke

“ Data of this kind, which are by other means inaccessible to the astronomer, are obviously indispensable to any adequate conception of the stellar system as a whole or in its parts. In solar physics Huggins suggested a spectroscopic method for viewing the red prominences in daylight; and his experiments went far towards settling a much-disputed question regarding the solar distribution of calcium. In the general solar spectrum this element is represented by a large number of lines, but in the spectrum of the prominences and chromosphere one pair only can be detected. ”

“ HUGGINS, SIR WILLIAM (1824–1910) , English astronomer, was born in London on the 7th of February 1824, and was educated first at the City of London School and then under various private teachers. Having determined to apply himself to the study of astronomy, he built in 1856 a private observatory at Tulse Hill, in the south of London. At first he occupied himself with ordinary routine work, but being far from satisfied with the scope which this afforded, he seized eagerly upon the opportunity for novel research, offered by Kirchhoff’s discoveries in spectrum analysis. ”

“ The striking discovery was, in 1903, made by the same investigators that the spontaneous luminosity of radium gives a spectrum of a kind never before obtained without the aid of powerful excitation, electrical or thermal. ”