BEARINGS OF RADIOACTIVITY ON GEOLOGY 695 



this paper the selective influence of strains on fusion and solution 

 was cited. There seems little doubt that a similar influence is 

 exerted by the great zones of strain that are developed in the earth 

 by diastrophic agencies. Among the tentative distributions of 

 these under study, a specific system seems more probable than 

 others and this is of such a nature as to direct fluid matter, par- 

 ticularly any that may arise at considerable depths, toward the 

 lines that are affected by volcanic extrusions. 



