74 Mr. W. Makower on the Molecular 



Experiments were next made to determine the value of 

 Xt. The porous vessel (V) was replaced and a current of 

 about 170 c.c. per minute passed through the apparatus. 

 The results of these experiments are given in Table VII. 



Table VII. — Diffusion of Radium Emanation. 



Gasometer fell *564 mm. per minute. 



The Current of Emanation was started at 12.51 p.m. 





Leak for 30 seconds, in scale-divisions 







of the electrometer. 





Time. 







Vessel A. 



Mean. 



Vessel B. Mean. 



3.03 p.m. 



166 









3.06 „ 



... 





88 







3.09 „ 



168 











3.12 „ 







92 







3.18 ., 



176 











3.21 „ 







93 







3.24 „ 



180 











3.27 „ 







96 







3.30 „ 



179 









3.33 „ 





99 





• 



3.36 „ 



168 171 



... 



89 





3.39 „ 





87 







3.42 „ 



172 











3.45 „ 







88 







3.51 „ 



176 











3.54 „ 







90 





3-57 „ 



169 











4.00 „ 







83 







4.03 „ 



170 









4.06 „ 







82 





4.09 „ 



166 







4.12 „ 





80 





4.15 „ 



164 







4.18 ., 





87 





9. Experiments ivith Thorium Emanation to determine 



log — and log— - /e 



The radium solution was removed and replaced by a wide 

 lead tube containing thorium oxide wrapped in filter-paper 

 over which a current of air could be passed into the vessel 



