BUILDING OF LIVING MATTER 107 



I 



C 

 / % 



-c c- 



II I 

 -c c- 



\ s 

 c 



I 



(3) 



so leaving each carbon atom with only one 

 free centre of activity. 



Now these formulae do not represent actual 

 organic substances, but only structures on 

 which molecules can be built up ; none of 

 them can exist unless the free activities are 

 taken up by other atoms or groups of atoms. 

 Take the simplest case, that each of the free 

 positions is taken up by a hydrogen atom (H). 

 Then the schemes represent actual existing 

 bodies called hydrocarbons. The third one 

 would represent the molecule of the well- 

 known substance benzene, or benzol, the first 

 one a known hydrocarbon, hexane, and the 

 second one a reduced benzene (hexa-hydro- 

 benzol). 



Very many other groupings than simply 

 putting in hydrogen atoms can evidently be 

 made, and hence without any reduplication 



