840 



LORD KELVIN. 



CO, SO,Na C/(dry common sait) if each single atom, 0, N } H, Cl, C, *) 

 8, Na, 2 ) had just one electrion for its neutralizing quantum. If the 

 combination is so close that the centres coincide, the two electrions will 

 rest stably at equal distances oii the two sicles of the common centre 

 as at the end of § 9. I see at présent no reason for considering it ex- 

 cessively improbable that tins may be the case for SO, or for any other 

 binary combinations of two atoms of différent qualifjj for neither of 

 which there is reason to believe that its neutralizing quantum is not 

 exactly one electrion. But for the binary combinations of two atoms of 

 identical quality which the chemists have discovered in diatomic gases 

 (0 2 , N 2 , etc.) there must, over and above the electric repulsion of the 

 two similar electric globes, be a strong atomic repulsion preventing 

 stable equilibrium with coincident centres, however strongly the atoms 

 may be drawn together by the attractions of a pair of mutually 

 repellent electrions within them ; because without such a repulsion the 

 two similar atoms would become one, which no possible action in nature 

 could split into two. 



§11. Eeturning to § 9, let us pull the two atoms gradually asunder 

 from the concentric position to which we had brought them. It is easily 

 seen that they will both remain within the smaller atom A, slightly 

 disturbed from equality of distance on the two sides of its centre by 

 attractions towards the centre of A'; and that when À is infinitely 

 distant they will settle at distances each equal to | <% |K 2 — '62996,% 

 on the two sides of C, the centre of A. If, instead of two monelectrio- 

 nic atoms, we deal as in § 9 with two polyelectrionic atoms, we fincl 

 after séparation the number of electrions in the smaller atom increased 

 and in the larger decreased; and this with much smaller différence of 

 magnitude than the three to one of diameters which we had for our 

 monelectrionic atoms of §9. This is a very remarkable conclusion, poin- 

 ting to what is probably the true explanation of the first known of the 



a ) The complexity of the hydrocarbons and the Van 't Hoff and Le Bel doc- 

 trine of the asymmetric results (chirality) produced by the quadri valence of carbon 

 makes it probable that the carbon atom takes at least four electrions to neutra- 

 lize it electrically. 



2 ) ïhe fact that sodium, solid or liquid, is a metallic conductor of electricity 

 makes it probable that the sodium atom, as ail other metallic éléments, takes 

 a large number of electrions to neutralize it. (see below § 30). 



