40 THE NEW KNOWLEDGE. 



parts, then the fact of relationship may be explained in" a 

 simple, rational manner. 



For if the atoms are not simple, but on the contrary are 

 made up of component parts, then these parts would, of 

 course, unite together in certain numbers and in certain 

 ways to constitute the composite bodies we call atoms; 

 just as the atoms unite in various numbers and in various 

 ways to constitute the molecules of compounds, and it is 

 reasonable to assume that they actually would do so. Thus, 

 among the compounds of carbon, we are acquainted with 

 series of compounds, which in variations of molecular weight 

 and gradation of properties bear a striking resemblance to 

 the elements when arranged after the fashion of the 

 Groups in the periodic law. For example, we have the 

 series: 



Molecular weight. 



CH 4 Methane 16 



C 2 H 6 Ethane 30 



C 3 H 8 Propane 44 



C 4 H 10 Butane 58 



C 5 H 12 Pentane 72 



and a list of others up to a compound of the formula 

 QjoH 62 i n which, with a regular increase of 14 in the 

 molecular weight, there is a regular variation in their prop- 

 erties in such a way as to constitute them a definite group. 

 Therefore, if groups of atoms may unite together to form 

 bodies with correlated properties and group relationships, 

 why should not groups of sub-atoms unite together to form 

 the atoms with similar group relationships ? Again, in 

 chemistry, we occasionally find little groups of atoms 

 actually playing the role of elements. Thus, the little 



