308 Prof. W. D. Harkins on the 



2 (a). Atoms in which P is even are considerably more 

 abundant than when P is odd ; about 18 times as 

 abundant in the meteorites and 6^ times in the earth's 

 crust. It will be seen that these ratios are not so large 

 as those presented under 1, which is the more striking 

 and important correlation. 

 (b). Either the nuclei, or the electron-proton groups in 

 nuclei, are in general more stable when the number of 

 protons is even than when it is odd. 



3(a). Atoms in which M or P — N is even are very much 

 more abundant than those in which M is odd ; about 

 50 times in the meteorites, and 8 times in the crust of 

 the earth. 



It is thus apparent that P — N is more often even than 

 either N or P. 



4 (a). Atoms in which N is odd and P is even are extremely 



rare, being represented by O'OO per cent, in the meteorites, 

 the same percentage in the lithosphere, and by about 

 0*05 per cent, in the lithosphere, atmosphere, and hydro- 

 sphere, if the estimates are made from the collected 

 quantitative analyses, account being taken of the 

 existence of isotopes. An hypothesis to account for 

 this relation will be given later, since it is intended to 

 include in this section only those hypotheses which are 

 simply statements of the facts in the language of 

 electrons. 



5 (a) . No SPECIES OF ATOMS WHICH HAS BEEN FOUND TO EXIST 



EITHEE ON EARTH OB IN THE METEORITES HAS A VALUE 



FOB N/P of less than \ or 0*5. It is somewhat re- 

 markable, too, that in most of the atoms which exist the 

 ratio N/P is exactly 5, such atoms making up about 

 80 per cent, of the meteorites and 85 per cent, of the 

 earth's crust. The value of N/P is given by a function 

 which increases with increasing P — N 5 or M. The 

 general form of this function is represented on an N/P, 

 M plot by a curve which has very nearly the form of 

 one limb of one branch of an hyperbola, with the node 

 at M = 0, and N/P = 0'5. (See PL XII. fig. 1.) 



TL r Number of Nuclear Negative Electrons 



„'' A Number of Nuclear Positive Electrons 



is of fundamental importance in connexion with atomic 

 stability and abundance. The hypotheses based upon 

 this correlation are of such importance that they will be 

 reserved for a separate section of the paper. 



