68 ROYAL SOCIETY OF CANADA 
tions were boiled vigorously for 8 minutes or for 20 minutes. After 
deducting the small natural leak of the electroscope, the results ex- 
pressed in divisions per minute were as follows:— 
Divisions 
No. per min. Per cent. 
ie Blanks Ve see ee es ARR" 4.38 100 
DB) ASAT, oe Ree cog ee es chan JR 4.37 100 
SA MARO PEL ec ey Cr PEU 4.15 95 
Me HG Grae ATO te SU ee 4.22 96 
Ss 10cm BAG 10). oe 
LCI ee se teen ee 0.58 13 
GPL pram barite” ete oe ae 27 
It will be seen that while the addition of H,SO, reduced the 
amount of radium emanation liberated by only 4 or 5 per cent., the 
1.4 grams of Ba SO, reduced the yield to one quarter of the amount 
present, and the barium chloride and sulphuric acid together permitted 
but one-eighth of the radium emanation to escape. These results are 
very remarkable when it is remembered that the amount of radium 
bromide present was only 7.8 x 107! grams. They appear to indicate 
that the precipitated barium sulphate in the fifth flask occluded the 
radium and thus checked the escape of the emanation. 
In the sixth sample the low determination of the emanation ap- 
pears to show that the barium is more soluble than the radium. 
The writers propose to carry out further experiments in order to 
elucidate these peculiar reactions as far as possible. 
