May 17, 1888] 



NA TURE 



Fig. 8. — Map showing the lines, bands, and Outings seen in the spectra of the elements which are indicated in bodies of Group II. The map is intended to show 

 also the relative intensities of the different lines, bands, and flutings, the lines, &c, seen in the lowest horizon being those seen at the lowest temperature. 



I 2 



HOT CARBONS 



MAGNESIUM. 



MANGANESE 



RESULT , SPECIES 2. 



RADIATION 



ABSORPTION 



HOT CARBON 



MAGNESIUM. 



MANGANESE. 

 RESULT, SPECIES 3 



HOT CARBON 



MAGNESIUM. 



MANCANESE. 



RESULT, SPECIES 5. 



RADIATION 



ABSORPTION 



RADIATION. 



ABSORPTION 



Fig. 



9.— Diagram showing the effects of variations in width of the flutings of carbon upon the integrated spectra of carbon radiation, and magnesium and 

 manganese absorption, as they occur in different species of bodies of Group II. The carbon radiation alone would give bright bands, while the 

 absorption alone would give dark ones ; but if the bright and dark bands fall in the same regions of the spectrum, the result will be enfeebled 

 radiation, enfeebled absorption, or nil, according to the relative quantities of radiating and absorbing substances present. Thus, in species 2, the 

 magnesium fluting at 500 15 masked by the carbon fluting at 517, but as the quantity of carbon diminishes, it appears as an abiorption band. 



