242 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 19 31 



other diagonal are approaching. Figure 3 shows the resulting dis- 

 tribution of radial motion (ignoring the transverse motion which is 



-> 



-> 



-^ — 



~> 



-> 



o 



rn 

 Fig. I. 



3 

 O 



rn 

 Fig. 2. 



\ 



^ 



•H 



/^ 



\ 



Fig. 3 

 Distribution of radial velocity 



not detected by the spectroscope). It will be seen that the distribu- 

 tion of motion is of the kind which distorts a square into a diamond. 



