32 THE ROYAL SOCIETY OF CANADA 



errors were made in their preparation, we should expect the solution 

 standards to come out similarly. This work shows fair agreement — 

 about 3% low, whereas the solid standard is 4 • 9% low. 



2. The strong and the weak solutions of the Rutherford- 

 Boltwood Standard, prepared in the ratio of 100:1, turn out to be 

 in fairly good agreement — probably within 2%. This shows that no 

 serious deterioration has occurred with time. 



3. It has been found that a radium bromide solution deteriorates 

 with each boiling. Also that if a sufficient amount of hydrochloric 

 acid, free from radioactive matter, is added, the solution will recover 

 its normal emanating power. The cause of this has not yet been 

 ascertained. 



May 22, 1915. 



Montreal. 



