756 Prof. H. E. Armstrong on Low-Temperature Ressarch 



described at the Chemical Society, on November 4, 1897, in an 

 address given by Prof. Dewar, then the President of the Society, 

 under the title "Liquefaction of Air and the Detection of Impurities." 

 There is no doubt that the information revealed in this paper gave 

 Ramsay and Travers a clue to the presence of unknown gases in the 

 air as well as to the method of isolating them and that it w^as the 



IL 



To Gasholder 



Apparatus for the examination oFthe 

 least condensible portion of Air. 



~^ 



Fig. 1. 



cause of their intrusion into this field of work. Prof. Dewar's course 

 of action, up to this date, had been systematic and logical ; he had 

 endeavoured, as far as possible, with the very limited means at his 

 disposal, to exploit the opportunities, which he was continually extend- 

 ing, of studying low-temperature phenomena ; and he had long been 

 eng ged in collecting gas given off from the Bath springs with the 



