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ROYAL SOCIETY OF CANADA 



20°C and under identical experimental conditions, for water and for 

 coal oil. It turns out that for thorium emanation as well as for ra- 

 dium emanation the oils from petroleum are the best liquid absorbers. 

 The non-absorption curve shown was obtained by filling the space which 

 had been occupied by the liquid under investigation with mercury, 

 and making the tube which delivered the emanation end at the 

 mercury surface. 



Other curves taken show that sulphuric acid absorbs only slightly 

 more than water (in fact their absorptive powers may be considered 

 equal), and that ethyl alcohol (absolute) is intermediate between 

 water and petroleum in its absorptive power, 



TABLE I. 



Multiply currents by 195 x 10"''* for amperes. 



We may write the solubilities of these common liquids in the 

 ascending order: — 



Distilled water 



Sulphuric acid. 



Ethyl alcohol. 



Petroleum 

 The solubilities of radium emanation in the same liquids are in this 

 order also. 



