NO. II STRUCTURE OF THE ATOM PARSON 69 



to form a new group of eight that is characteristic of the " negative " 

 atoms : this destroys the paramagnetism. If Phosphorus, Sulphur, 

 or Chlorine atoms were isolated, they might be found to be para- 

 magnetic (it may be possible to test this with monatomic Iodine gas) ; 



but the ordinary state of Chlorine is (Cn\Cv , in which all the mag- 

 netons are bound for most of the time (see §9), while the complexity 

 of the gaseous molecules of Sulphur and Phosphorus leaves little 

 doubt that most of the valence magnetons are in groups of eight or 



LS 



s = s 



double positive bonds a as in % // , CPj= P = P ^Pj ' etc 



In the first short period, the diamagnetism of Boron (y + 3) is 

 explainable on the principles already set forth ; and the striking 

 feature is the strong paramagnetism of the Oxygen (y + 6) molecule 

 as compared with the comparative magnetic inertness of the Nitrogen 

 (y + 5) molecule. The only available determinations for Nitrogen 

 appear to be Quincke's, who gives for the susceptibility per cc. 

 + .001 at 1 atm., and + .04 at 40 atm. : these are evidently more 

 reliable than his values for Hydrogen, but there is the possibility 

 here of contamination with Oxygen. 



As for Oxygen, since in oxides, such as \jOj, Ca^O ), it is 



invariably diamagnetic, its paramagnetism in the molecular state has 

 led J. J. Thomson and others to suppose that one of the two atoms 

 is acting " positively." This, according to the present theory, would 



be represented by ( Oy= O , which formula has already been given 



in §9: there it was supposed that the molecule had another phase 



containing the double negative bond: (o4o). If the existence of 



the first phase is the true explanation of the paramagnetism of the 2 



molecule, we should expect the N 2 molecule, (N^N , to be para- 



1 A double positive bond is expected to have no magnetic moment, as will be 

 shown in a future paper : as we have seen for the H? molecule, a single positive 

 bond need have none. 



