422 ASTRONOMY: SHAPLEY AND NICHOLSON 
The last three columns of the table show that, if the pulsation 
hypothesis is correct, the measured range in velocity is about 75% of 
the actual variation at the center of the disk. 
a b 
0 0 0.2 0.4 0.6 0.8 0.0 0.2 0.4 0.6 
FIG. 3 
There is considerable uncertainty in measures of the widths of ab- 
sorption lines by ordinary methods, but it has been assumed that the 
measured widths lie between intensities of I 7$, where Iq is the in- 
