in the Spectrum of the Solar Atmosphere. 7 357 
choff and Angstrém which accompany their respective 
atlases. In the preliminary catalogue the numbers were derived 
om the maps; hence some slight discrepancies in the tenths 
of division. 
The fifth column, marked F, contains a rough estimate of 
the percentage of frequency with which the lines were seen 
ring the six weeks of observation ; and the sixth column, B, 
4 similar estimate of their maximum brightness compared with 
that of the hydrogen line C. 
1€ variations of brilliance, however, when the chromosphere 
Was much disturbed, were so considerable and so sudden that 
no very great weight can be assigned to the numbers given. 
Nor is it to be inferred that lines which have in the table the 
Same index of brightness were always equally bright. On cer- 
tain occasions one set of lines would be particularly conspicu- * 
atts’ Index of Spectra.” Since the positions of the lines in 
the latter work are given only to the nearest unit of “Angstrém’s 
Scale,” I have marked the coincidences indicated by it with a (w), 
* 
Considering them less certain than those shown by the maps. 
