620 Dr. A. C. Crehore on the Construction of 



This process may be continued by adding a fifth OFi 2 molecule, 

 making the compound O 5 H 10 , as in fig. 11, and a sixth making 

 the compound C 6 H ]2 , as in fig. 12. Each successive addition 

 enlarges the diameter of the ring, but the process cannot be 

 kept up indefinitely, because finally a point is reached where 

 the forces acting upon one of the OH 2 molecules become 

 unstable in a direction perpendicular to the plane of the 

 ring. There is a contest between the carbon and the hydrogen 

 atoms in this respect. When a carbon atom is displaced 

 perpendicular to the plane of the ring, the other carbon 

 atoms tend to push it further away and make for instability; 

 but if a hydrogen atom is so displaced, the other atoms in 

 both the hydrogen rings tend to restore it and make for 

 stability. The determination of the limit by means of the 

 graphical charts has not been done because it has become 

 evident that the required degree of accuracy is not obtainable. 

 To find this limit a special investigation making use of the 

 equations seems imperative, and this should be undertaken. 



The Chain Formation. 



Returning again to the molecule ("H 4 , methane, shown in 

 fig. 7, there is another fundamental way in which compound 

 molecules may be formed. By adding a molecule of OH 2 on 

 the side of this methane molecule the compound C^H 6 may be 

 formed, and the process may be continued almost indefinitely, 

 forming a long molecule in the shape of a chain, which 

 chemists express by the structural formula as follows: — 



H H H H H H 



I I I I I I 

 H— C— 0— 0— 0-C— C— H 



I I I I I I 

 H H K H H H 



The molecule representing this is shown in perspective 

 view as a chain of tetrahedra in fig. 13. When the first 

 molecule of CH 2 is added to the original CH 4 , the two 

 carbon atoms being located each on the equator of the other 

 strongly repel each other, and cause a great distortion of the 

 original methane tetrahedron. The two central hydrogen 

 atoms become separated to a much greater distance than they 

 formerly were, but the two pairs of hydrogen atoms at the 

 ends are not so separated. In each of the systems it is seen 

 that the hydrogen pla}'S the part of binder for the carbon 

 atoms. In fig. 13 the six carbon atoms are in a straight line, 

 each strongly repelling the other. An atom in the middle 



