Connexion between the Atomic Weights. 115 



elements from ruthenium to samarium. In this case 



2 loo- w 



log 1 62 —log 144 



= 1-211. 

 If, however, we leave the gap, we hav< 



2 log w 



log 1 63 — log |16 

 = 1-205. 



Thus the q when we leave no gap is nearer to the first value 

 (</ = 1*209) than is the value of q obtained when we leave the 

 gap. This leads to the conclusion that no element of atomic 

 weight about 101 with properties aualogous to manganese is 

 to be predicted. 



The mean value of q can now be calculated from 



__ 2 log tv 

 2~log|62-log|8' 



which gives 



2 = 1-210. 



When the value of q has been determined as accurately as 

 possible, then the formula may be employed to determine 

 what empty places in the periodic table are to be filled by 

 predicted elements, in the same way as has been already done 

 above on the assumption that ^ = 1*21. 



Conclusion. 



The consequence which follows from the assumption that 



W=N*, 



where N is a -f integer and qu positive number whose actual 

 value approximates to 1*21, is that the list of atomic weights 

 starts abruptly at hydrogen but has no end. 



The fact that for many years all the elements that have 

 been discovered have atomic weights greater than that of 

 hydrogen and less than that of uranium would point to the 

 conclusion that any law for the connexion between the masses 

 of different kinds of atoms should lead to the list of elements 

 being limited at both the beginning and end. 



Cavendish Laboratory, 

 Cambridge. 



12 



