November 9, 1917] 



SCIENCE 



445 



Atomic Number 

 Fig. 3. The abundance of the elements in the 

 meteorites. Every even-numbered element is more 

 abundant than the tvs-o adjacent odd-numbered ele- 

 ments. 



not exhibit any special fondness for the 

 even-numbered elements in comparison 

 with the odd, or, vice versa, any more than 

 the earth or the sun as a whole, at least not 

 unless there is an important difference be- 



tween these two systems of elements, which 

 is just what it is desired to prove. A study 

 of the compilations made by Farrington, by 

 Merrill, and by other workers of analyses of 

 meteorites, has given some very interesting 

 results. 



The results shoiv that in either the stone 

 or the iron meteorites the even-mimbered 

 elements are very much more alundant 

 than the odd. Thus in the iron meteorites 

 there are aiout i2j times more atoms of 

 even atomic number than of odd, while in 

 the stone meteorites the even-numbered ele- 

 ments are about 47 times more abundant. 

 If we average the 125 stone and 318 iron 

 meteorites given by Parrington, it is found 

 that the weight percentage is 98.78 for the 

 even and 1.22 for the odd-numbered ele- 

 ments, or the even-numbered elements are 

 about 81 times more abundant. 



If we consider these same meteorites, 443 

 in all, and representing all of the different 

 classes, it is found that the first seven ele- 

 ments in order of abundance are iron, oxy- 

 gen, silicon, magnesium, calcium, nickel 

 and sulphur, and not only do all of these 

 elements have even atomic numbers, but in 

 addition they make up p8.6 per cent, of the 

 material of the meteorites. 



Table IV. gives the average composition 

 of these meteorites. The numbers before 

 the symbols are the atomic numbers, and 



Average Composition of Meteorites 



TABLE IV 



Arranged According^ to the Periodic System 



