CHAMBERLIN— THE AGE OF THE EARTH. 269 



water equilibrium conditions wouM be expected to remove readily a consid- 

 erable amount of the NaCl while the K2O would be largely retained on the 

 weathering of the shale and the reformation of colloids resulting therefrom. 



From these authoritative statements of present knowledge and 

 opinion ; from the early experiments of Way, Eichhorn, Kullenberg, 

 Voelcker, Lemberg, and others, in mingling soils with salt solutions 

 and in passing salt solutions through soils, and from many inter- 

 mediate experiments cited by Sullivan,-*' there is left little ground for 

 doubt that when the acid radicals previously separated from the basic 

 radicals under conditions of very low concentration, again meet basic 

 radicals under conditions of high concentration in the ocean ofif the 

 mouths of the streams, reunion takes place in equilibrium proportions. 

 The experiments of Lemberg are particularly instructive on this point. 

 He treated potassium-aluminum silicates with sodium-chloride solu- 

 tions of different degrees of concentration, and after thoroughly 

 washing the solid material so treated found that potassium had been 

 replaced by sodium in increased quantities as the concentration of the 

 sodium solution was increased. Complete replacement of the potas- 

 sium by the sodium did not take place, but only replacement to the 

 degree required by the law of equilibrium. Now if, in addition to 

 laboratory results, we recall that in former times salt water was 

 freshened for use by passing it through soil, the periodic flooding of 

 the border waters of the ocean by soil wash from the lands may be 

 looked upon as a natural process of salt-water freshening. As there 

 was wash from all the lands, and as the shales formed from the wash 

 products are known to make up much the largest part of the sedi- 

 ments, the process was really one of great magnitude. 



As the recombinations are divided among the constituents in 

 accordance with the law of equilibrium, the sodium gets a smaller 

 share than the potassium, but it gets a share. From the imperfect 

 evidence one may guess that the sodium recombines to a third or a 

 fourth of the extent of the potassium, but whether more or less than 

 this proportion, it seems clear that enough sodium reunites with the 

 acid radicals in their solid state to vitiate the use of sodium solutions 

 as a criterion of age. This is as far as the present issue requires me 



26 Eugene C. Sullivan, " The Interaction between Minerals and Water 

 Solutions with Special Reference to Geologic Phenomena," Bull. No. 312, U. 

 S. Geo!. Surv. (1907), pp. 7-62. 



