PHYSICAL SCIENCES 55 



was enhanced in interest by the presence of members 

 of I/ Association Frangaise pour FAvancement des 

 Sciences, who attended the meeting of the British 

 Association from their own meeting-place at Boulogne 

 across the Channel. Thomson's paper was followed 

 in the programme by one on the controversy concern- 

 ing the seat of Volta's contact force from Sir Oliver 

 Lodge, who has told the compiler of this record how 

 he could not refrain from continuing to discuss the 

 preceding ' epoch-making communication/ so that his 

 own subject received scant attention. Again, at the 

 Leicester meeting in 1907, there took place what Sil- 

 vanus Thompson l has described as ' one of the most 

 instructive discussions ever known in the Association,' 

 on the constitution of the atom, opened by Professor 

 [Sir] Ernest Rutherford. In this there took part 

 Sir Oliver Lodge, Sir William Ramsay, Professor 

 Frederick Soddy, Sir Joseph Larmor, and finally 

 Kelvin, whose last public appearance this meeting 

 proved to be; he died at the end of the same year. 

 Kelvin's activities at Leicester, in his eighty-fourth 

 year, brought fittingly to a close his unremitting 

 attachment to the interests of the Association. He 

 had proposed the vote of thanks to Gill for his presi- 

 dential address ; he had read a paper on the motions 

 of ether produced by collision of atoms or molecules 

 containing or not containing electrons ; and now he 

 keenly entered into debate, holding as he did that the 

 atom was an indivisible unit, and that therefore it 

 could not, as such, be said to possess a constitution. 



Lastly, the discovery of X-radiation, apart from 

 its now familiar and infinitely valuable benefits to 



1 Life of Lord Kelvin, p. 1201. 



