488 Albert P. Mathews 



from mathematical reasoning, that the attraction between 

 such magnets would be inversely as the yth or 9th power of 

 the distance, and thus agree with the assumptions of his father, 

 that molecular attraction diminished at such a rate that it 

 was effective only when the molecules were in contact. Later, 

 Sutherland 1 concluded that cohesional attraction was due to 

 electrostatic affinity of these electron couples. Lodge 2 made 

 a similar suggestion. He thought some of the lines of force 

 between the atoms wandered outside the molecule to atoms of 

 other molecules and thus produced molecular cohesion. This 

 would make molecular cohesion of the same nature as chemical 

 affinity. While the relation between the two is close, both 

 being zero in the absence of an electric charge, or valence, 

 one is not causally dependent on the other, although both 

 depend on the valences. The attraction between the atoms 

 is probably of an electrostatic kind and, if so, should vary 

 inversely as the square of the distance. The atomic weight 

 does not appear to play a part in chemical affinity, for very 

 light elements may enter into very firm union. In cohesion, 

 molecular weight does play a large part; and while it is not 

 impossible that the cohesional attraction may be inversely 

 as the square of the distance, it is not probable, or at any 

 rate it has not yet been proved to general satisfaction. 



It seems much more probable to me that cohesion is more 

 closely related to magnetism than to electrostatic affinity 

 and I would raise the question whether magnetism is anything 

 else than molecular cohesion made apparent at distances 

 more than molecular. Is it not possible that molecular cohe- 

 sion, involving as it does both atomic and valence electrons 

 (atomic weight and valence) is due, perhaps, to the magnetic 

 effects produced by the movements of these electron couples? 

 In this view the atoms would be united by their electro- 

 static affinities and these same valences and the other atomic 

 electrons by their magnetic effects produce the molecular 



1 Sutherland: Phil. Mag., [6] 17, 667 (1909). 



2 Lodge: Nature, 70, 176 (1904). 



