Manchester Memoirs, Vol. Hi. (1908), No. 10. 27 



within the Daltonian atoms, of which at present we can 

 form no idea, we are entitled by all experience to push 

 the consequences of their physical interaction as far as 

 possible, without fear of meeting irresolvable contra- 

 diction. 



This digression, and the related postulate that the 

 simplest representation of nature is the most probable 

 and effective one, receive illustration from the outstanding 

 puzzle of the electron-theory, already referred to. Why 

 do positive electrons not exist ? Put in this crude way the 

 question is absurd. They do exist, and they are equal 

 quantitatively to the negative electrons ; otherwise 

 ordinary molecules would not be neutral. But why are 

 they apparently so different in structure, whereas we 

 should expect them to be mirror images of the 

 negative ones ? The phenomena in this domain recall 

 the other question, why have the albumens and most 

 other vital products evolved on this planet left-handed 

 optical structure ? It may be that the union of positive 

 with negative electricity is something much more in- 

 timate than mere orbital motion ; for the structure of 

 the nuclei of electrons is as yet totally unconceived. It 

 may thus be that in the one or more types of molecule 

 that happen to be practically amenable to the expulsion 

 of an electron into the open, it is the negative that can 

 be readily driven out. If the central nucleus which knots 

 together the field of force constituting a positive electron 

 were large, such as, eg., might be represented by a sphere 

 of electrification of atomic dimensions, the intensity of 

 its field of strain would be small throughout, its energy 

 and inertia would thus be slight, and its effects would not 

 be prominent except as a mere centre of attraction. All 

 electric inertia would then belong to the negative 

 electrons. Is there any other inertia belonging to the 



