Constitution and Stability of Atom Nuclei. 317 



Table III. 



Abundance or the Atomic Species in the Meteoeites as Classified 



ACCORDING TO THEIR IsOTOPIC AND CLASS ^UMBERS. 



(Atomic Percentage.) 



Isotopic Number 



=0. 



Isotopic Number 



=1. 



Class Number 



=1. 



Class Number 



=11. 



Atomic 







Atomic 







Number. 



Symbol. 



Per cent. 



Number. 



Symbol. 



Per cent. 



6 



C 



0-12 



11 



Na 



0-62 



8 







53-16 



13 



Al 



1-21 



12 



Mg Si 



9-86 



15 



P 



0-06 



14 



Si 28 



1382 



19 



K 



011 



16 



S 



1-46 



Total.. 





. 200 



20 



Ca 



0-97 









26 



Fe 52 



? 



Class 



Number = 



III. 



28 



* Ni 5y 



V 



12 

 14 



Mg* 



Si 29 



1-65 



Total. 



. 79-39 



1-53 



Class 



Number = 



IV. 



Total. 





. 318 



7 



N 



o-oo 





* 





Isotopic Number 



_2, 



Isotopic Number 



=3. 



Class Number 



=1. 



Class 



Number = 



=11. 



Atomic 







Atomic 







Number. 



Symbol. 



Per cent. 



Number. 



Symbol. 



Per cent. 



12 



Mg 26 



1-65 



. ] 7 



CI 



000 



14 



Si 30 



? 









Total. 



. 165 





Isotopic Number 



=4. 



Isotopic Numbei 



= 5. 



Class Number = 



I. 



Class Number = 



= 11. 



Atomic 







Atomic 







^Number. 



Symbol. 



Per cent. 



Number. 



Symbol. 



Per cent. 



22 



Ti 



0-005 



23 



V 



000 



24 



Cr 



0-13 



25 



Mn 



006 



26 



Fe5<> 



12-30 



27 



Co 



04 



28 



Ni 60 



0-50 



Total. 





.. o-io 



Total 



.. 12-93 





It is worthy of note tbat tbe above percentages, together with those of the 

 lower isotopes of iron and cobalt of isotopic number to 3, whose percentages 

 are not included, since it is uncertain as to their exact isotopic number, make 

 up 999 per cent, of all of the material of the meteorites, and the similar 

 atomic species, atomic numbers up to 28 and isotopic numbers —1 to 5, make up 

 99-9 per cent, of the earth's surface, which indicates that no increase in the 

 ratio of electrons to protons (JS r /l 3 ) is able to sufficiently stabilise atoms with a 

 positive nuclear charge greater than 28 as to make such atomic species any 

 considerable factor in the abundance rehd ions. The important feature of tins 

 relation is that the abundance does not jail ojf gradually but suddenly 

 remarkably enough the fall in abundance comes just beyond nickel, while nickel 

 is the first of the elements in the region of abundant isotopes. All abundant 

 atomic species have isotopic numbers 4 or less. 



