768 Sir J. J. Thomson on the 



example, in formic acid, H — G# , where each molecule 



contributes 120 to the specific inductive capacity : glycollic 



H /OH 



acid nitrate, ^<OC , where each molecule contributes 



HV \ 



215 : and formamide, H — C\ , where each molecule 



contributes 210. In other cases the axes of the various 

 doublets might point so that the different doublets opposed 

 each other, and the resultant was less than any constituent. 



Acetic acid, tt^^/'C — C \ , where each molecule only 



n / ' \OH 

 H 



contributes 20*2 to the specific inductive capacity, is a 

 conspicuous instance of this effect. 



Though there is no intra-molecular ionization in CO, yet 

 when CO enters as a radicle into. .organic compounds, as in 

 acetone, aldehyde, acetic acid, and similar cases, it acts as a 

 doublet ; this would seem to be an example of the effect, 

 alluded to on p. 770, of the presence of other molecules in 

 promoting intra-molecular ionization. 



In some molecules only a few of the molecules may be 

 charged, all the others being uncharged. Thus in hydroxyl 

 compounds the atoms in the radicle OH might be the only 

 ones with a charge ; in a case like water, however, there 

 are no grounds for supposing that one of the hydrogen atoms 

 is charged and the other uncharged : if both of the atoms 

 have a positive charge, the oxygen atom must have two 

 negative charges and there are in reality two doublets in 

 the molecule. 



The hydroxyl radicle OH may exist in the molecule in 

 two states, according as the oxygen atom in it has one or 

 two negative charges. If the oxygen atom has only one 



- + 

 charge, then — H will form a single doublet, and there 



need be no other doublet in the molecule. If, however, the 

 oxygen atom has two charges, as presumably it has in a 

 molecule of water, then there must be a positive charge 

 on some atom not in the hydroxyl radicle, and thus there 

 must be at least two doublets in the molecule. 



I should like to put forward the suggestion that the 

 difference between these cases from the point of view of 



