EFFECT OF PRESSURE UPON ARC SPECTRA. NICKEL. 



237 



TABLE IX. 



The following abbreviations are used to express the width of bright lines and of reversals m columns 8 

 and 9 :-s = slight, m = moderate, c = considerable, g = great, vg = very great, G = very very great. 



Other abBreviations are : -r = reversed, r. = reversal nearly symmetrical, r, = reversal on violet 

 of centre of bright line, b B = broadening nearly" symmetrical, b r = broadening greater toward 

 b v = broadening greater towards violet, V = line has vanished under pressure. 

 VOL. CCXV. -A. 2 J 



