896 Dr. A. C. Crehore 



on 



electrons around which is an outer ring like oxygen consisting of four 

 alpha-particles and eight connecting electrons. The total mass is thus 

 6x4=24, and atomic number 4+8 = 12. 



The isotopes of 25 and 26 are obtainable by inserting a hydrogen 

 atom into the inner ring as in Gl fig. lb, and as in Gl-2 kg. 1. These 

 additions do not affect the atomic number, which is 12 for all three 

 isotopes. 



Aluminium is based upon the boron atom just described to which the 

 oxygen atom is added. The mass is thus 11 '024 +16 = 27 -024, and the 

 atomic number 5+8 = 13 as it should be. The experimental isotopes 

 of Al have not been reported as yet. One and two hydrogen atoms 

 may be added to these rings without affecting the atomic number. 

 Thus the normal Al atom of mass 27'024 is rich in hydrogen, \diich is 

 not present in magnesium, and the extreme range of 90 cm. for the 

 particles from Al indicates the presence of hydrogen. As in the boron 

 atom the diameter through these hydrogen atoms is a line of weakness 

 because they are neutral atoms, so here this diameter is proportionally 

 weaker. It seems that the bombarding alpha-particles may easily break 

 this ring into two parts along this line of weakness and thus liberate 

 hydrogen with considerable energy in agreement with the observed 

 facts. 



Part II. 



Computation of the Distances between the Centres o 

 the Atoms forming Molecules. 



1. General Considerations. 



It goes without saying that all of the computations required 

 for the multitudinous combinations known to the chemist of 

 the atoms shown in fig. 1 have not been completed. But 

 the general formulse to which they are subject have been 

 developed, and their application to these forms will afford a 

 satisfactory test of these ideas. It seems best to have in 

 mind concrete forms with the understanding that the 

 exact positions of the electrons are subject to investigation. 

 Certain combinations have been calculated, and so far as 

 they go the results are in agreement with the known facts. 



Since the discovery by Laue of the diffraction patterns 

 produced when X-rays pass through a crystal, the distances 

 between the centres of the atoms in many crystals have been 

 accurately measured. There are not many dimensions in 

 the whole atomic realm in which one has such great con- 

 fidence as the distances between the centres of the atoms in 

 a crystal. The remarkable thing is that they are all of 

 substantially the same order of magnitude, equal to a small 

 number times 10 -8 cm. for all known solids and liquids 

 differing widely in atomic weight and number. The greatest 

 known distance between the nearest atoms in any solid is 

 probably within a factor of ten times the least known distance 



