234 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1925 



that organ at eacli of its parts to the action of all the radium radia- 

 tions. Each of these radiations evidently can and does have a 

 specific action which is further dependent upon the duration of the 

 action and its intensity. One immediately sees how difficult it is to 

 I)ick out a particular action so that it may exercise its particular 

 power. We may thus understand the complexity of the problems 

 which are met with in the employment of radium in therapeutics. 



