AND ITS SELF-CONSERVATION. 93 



theory the numbers representing the proportions in which 

 the elements combine have direct reference to the weights 

 of the combining atoms. For weight, as we have seen, is 

 simply the excess of attraction over centrifugal force in 

 the neighborhood of a gravitating body like the earth. 

 So that the relative weights of the atoms of different ele- 

 ments really means the relative excess of attraction over 

 centrifugal force as between the earth on one side, and the 

 atoms or force-centers in the elements taken severally. 



Now, the weight of an atom of hydrogen being taken 

 as 1, the weight of an atom of nitrogen is 14, and that of 

 an atom of oxygen is 16. But the simplest compound of 

 nitrogen and oxygen known to take place consists of two 

 parts of the former and one of the latter. Hence the 

 combining numbers for these two "elements" expressed 

 in their atomic weights are: 28 for nitrogen and 16 for 

 oxygen. And since the " atoms " can only combine as 

 wholes, the next more complex compound, supposing the 

 quantity of nitrogen to remain fixed, would be that in 

 which the quantity of oxygen would be doubled, and so on. 



Allowing, then, that the atom is real, not as an infin- 

 itely hard, absolutely fixed particle of something existing 

 independently of force, but rather as itself simply a focus 

 of force which constitutes a relation that must remain 

 fixed so long as the surrounding conditions remain ap- 

 proximately the same ; allowing this, we can see that the 

 law of multiple proportions only becomes the more sig- 

 nificant, without losing in any degree its simplicity. 



This law, indeed, but expresses the fixed relation be- 

 tween the general mass of the earth in its present rela- 

 tively matured stage of condensation and the various 

 classes of force-centers constituting, through their varied 



