28 Presidential Address 



and the skill with which it has been 

 worked out, yet thinks the evidence more 

 in favour of a minute ' central positive 

 nucleus, or nucleus-group, of practically 

 atomic mass; with electrons, larger i. e., 

 less concentrated and therefore less 

 massive than itself, revolving round it in 

 astronomical orbits. While from yet an- 

 other point of view it is insisted that 

 positive and negative electrons can only 

 differ skew-symmetrically, one being like 

 the image of the other in a mirror, and 

 that the mode in which they are grouped 

 to form an atom remains for future dis- 

 covery. But no one doubts that elec- 

 tricity is ultimately atomic. 



Even magnetism has been suspected 

 of being atomic, and its hypothetical unit 

 has been named in advance the magneton: 

 but I confess that here I have not been 

 shaken out of the conservative view. 



We may express all this as an invasion 

 of number into unexpected regions. 



Biology may be said to be becoming 

 atomic. It has long had natural units 

 in the shape of cells and nuclei, and some 



