RADIUM CONTENTS OF SOME NOVA SCOTIAN MINERALS 



175 



apparatus as a whole was 58 electrometer scale divisions per 

 11~" gram of radium per minute of time of charge. Thus by 

 taking 10 grs. of the mineral, a measurement could be made on a 

 specimen containing 10~'^ gram Ra. per gram. The following 

 results were obtained: — - 



Specimen 



Location in Nova Scotia 



Ra. content in grs.: 

 per gram of mineral. 



Common salt 



Malagash, Cum. Co. 



Less than 5x1 0"^'' 



Potash salt 



Malagash, Cum. Co. 



Less than 5x1 0"'"* 



Felspar (light) 



Governor's Lake, Hfx. 

 Co. 



8.7x10-'' 



Felspar (dark) 



Governor's Lake, Hfx. 

 Co. 



14.0x10"" 



Siliceous slate 



Upper Musquodoboit, 

 Hfx. Co. 



2.6xlC 



Remarks 



The dark felspar contained a number of dark coloured 

 impurities of which mica was one. The tests on the Malagash 

 deposit were suggested by Dr. Ellsworth, of the Geological 

 Survey of Canada, as possibly capable of throwing light on the 

 origin of that deposit. The measurements were made on both 

 the soluble and insoluble parts of the salt and no trace of radium 

 was found in either. Further measurements were cut short, 

 owing to the lack of time and to some difficulty in getting 

 samples. 



In conclusion, I wish to thank Dr. G. H. Henderson for 

 his kindly interest and guidance throughout the work. 



