484 POPULAR LECTURES AND ADDRESSES. 



apparatus but apparatus merely of the lecture- 

 illustration kind could teach. But there was 

 absolutely no provision of any kind for experi- 

 mental investigation, still less idea, even, for any- 

 thing like students' practical work. Students' 

 laboratories in physical science were not then 

 thought of. I remember one of the chemists of 

 the Liebig school asking me what was the object 

 of a physical laboratory. I replied that it was to 

 investigate the properties of matter. I could give 

 no better answer now. I may remind you that 

 there is no philosophical division whatever between 

 chemistry and physics. The distinction is that 

 different properties are investigated by different 

 sets of apparatus. The distinction between chem- 

 istry and physics must be merely a distinction of 

 detail and of division of labour. 



Soon after I entered my present chair in the 

 University of Glasgow in 1846 I had occasion to 

 undertake some investigations of certain electro- 

 dynamic qualities of matter, to answer questions 

 which had been suggested by the results of 

 mathematical theory, questions which could only 



