'8 WlLDE, Points of Chemical Philosophy. 



through its halogen combination, into helium was naturally 

 received by chemists with some degree of scepticism and 

 incredulity. The peculiar circumstances, however, under 

 which the transmutation was effected through Rutherford's 

 previous suggestion that the emanation from a radium 

 compound might resolve itself into helium, brought with 

 it an amount of conviction sufficient to establish the reality 

 of the transmutation in the minds of those who had closely 

 followed the course of the investigation. 



More recently, Himstedt and Meyer, 1 Giesel 2 and 

 others, by exhaustive and decisive methods, have con- 

 firmed the experimental results previously obtained by 

 Sir W. Ramsay and Mr. Soddy, so that the transforma- 

 tion of radium combinations into helium has now the 

 certainty of any well established fact in the natural 

 sciences. 



I may here be permitted to express my satisfaction 

 on the confirmation of the views and previsions advanced 

 in my former papers, especially in connection with the 

 transformation of radium into helium, and the places 

 assigned to these elements in my tables previous to their 

 discovery. 



In the first demonstration of the transformation of 

 radium bromide into helium, Sir W. Ramsay was careful 

 to point out that the transformation was not brought 

 about directly, but through a gaseous emanation evolved 

 from the radium bromide. He describes the emanation 

 as a new elementary substance resembling members of 

 the argon family in its chemical inertness. Hence, we 

 have an actual transformation of radium bromide into 

 the elementary emanation. Now, as no suggestion has 

 been made that elementary bromine was evolved in a 



1 Ann. d. Physik, Sept., 1904, Sept., 1905. 

 • Berichte, vol. 38, p. 2299, 1905. 



