148 SIR WILLIAM RAMSAY 



molecules and the mass of the central body. The 

 composition of the earth's atmosphere, the absence of 

 atmosphere around the moon and the composition of 

 the solar atmosphere, which contains hydrogen and 

 helium mixed with heavier gases, are thus explained, 

 and it appears that a gas of lower density than ammonia 

 would sooner or later disappear from the earth. Hence 

 any helium in our atmosphere would escape sooner or 

 later. 



The annual meeting of the Chemical Society was this 

 (1897) year marked by two events, both of which testify 

 to the position Ramsay occupied in the esteem of the 

 chemists of his own country. The presentation of the 

 LongstafE Medal, " for the discovery of helium and for 

 his share in the investigation of argon," represented 

 only another unit in the long series of prizes and dis- 

 tinctions which had fallen to his lot, and being available 

 only once in three years, this was the first opportunity 

 for the award of the medal by the Council. This year, 

 however, was the unprecedented occasion of a division 

 in the Chemical Society in regard to the nomination of 

 President. In accordance with custom the new presi- 

 dent was nominated by the Council for election at the 

 annual meeting. A considerable number of the Fellows, 

 however, being desirous of seeing Ramsay in the chair, 

 proposed him formally in opposition to the official 

 nominee. That this was done without his knowledge 

 is shown by a passage in a letter to his friend Fyfe, 

 dated the 21st March, ten days before the anniversary, 



