12 RUSS, Note on Radio-active Recoil. 



Inspection again shows that the experimental points 

 lie within the limits imposed by the two cases considered. 



This result confirms the impression already obtained 

 that the numbers of Radium A and Radium B particles 

 projected up the tube are not very different. 



It was thought unnecessary in the analysis to allow 

 for the difference in the ionisation produced by the r 

 particles from Radium A and Radium C. 



Conclusion. 



It has been seen that the experimental results obtained 

 may be explained on the supposition that Radium A and 

 Radium B particles are projected in about equal propor- 

 tions from the Radium Emanation when it is condensed 

 at the bottom of a tube from which the air has been 

 removed. 



If Radium C were radiated in anything like the 

 same proportion the experimental decay curves would 

 be markedly different. Some recent experiments by 

 Dr. Makower and the Author have shown that the 

 number of Radium C particles which effectively recoil as 

 the result of the ejection of beta particles from Radium B 

 is a very small fraction of the number of Radium A and 

 Radium B particles which do so as a result of the ejection 

 of alpha particles from Radium Emanation and Radium A 

 respectively. 



