156 ELECTRIC VIEW OF MATTER [CH. xvi. 



by the facts of cohesion. For a diagram representing 

 the state of things intended, see fig. 20. 



To investigate the actual law of force would be 

 difficult, and too many assumptions would have to be 

 made for the geometrical arrangement of the electrons 

 in the adjacent atoms ; it could only be approximate, 

 because we should probably, at least in the first 

 instance, have to assume a static distribution. 

 Nevertheless the attempt might be instructive, and 

 might in a developed form be suitable for an Adams 

 Prize Essay. 



o o o 0*0*0*0 



0*0*0*0 o o o 



* 0*0*0* 0*0*0*0 



0*0*0*0 o o o 



0*0*0* 0*0*0*0 



A B 



FIG. 20. Ordinary Cohesion between two Neutral Atoms A and B : 

 each atom supposed to consist of interleaved electrons of opposite sign 

 depicted in any convenient way which attract each other by residual 

 or spare affinity. This is due to a few of the lines of force which stretch 

 across the interspace, and hold the pair of atoms together. The maxi- 

 mum distortional shear permissible depends on the ratio of the electronic 

 to the atomic distance. 



It is quite plain, however, that the result would be 

 a force rapidly increasing and becoming great at 

 small distances, and practically nil at any perceptible 

 distance. 



A theory of cohesion cannot really be given until 

 the structure of an atom is better known, but in 

 all probability it will proceed on lines not wholly 

 unlike the above. 



Molecular forces on this view are electrical, just as 

 much electrical as are chemical forces ; but they occur 

 between chemically saturated molecules, and are due 

 to the interaction or distant influence of paired 



