Ether and Energy in Evolution of Matter 11 



The granite shell or crust contained either in its own con- 

 stitution, or enclosed as graphite masses (in the case of carbon), 

 or included as gaseous cavities, all of the elements that make 

 up organic bodies. Furthermore, abundant and varied com- 

 binations had already taken place among the elements, so 

 as to produce granitic compounds, from which, by subsequent 

 alterations, disintegration, and reintegration, all of the more 

 recent rock constituents could be derived. 



If we now compare the views of physicists and geologists, 

 as to the probable age of the earth's crust from the time when 

 the granitic rocks had been formed up to the present day, a 

 considerable diversity of opinion is encountered. Kelvin, in 

 his earlier calculations, based his estimates on three physical 

 factors, and concluded that a period of from 20,000,000 to 

 100,000,000 of years has elapsed since subaerial denudation 

 and deposition began to take place. But the more recent 

 studies of G. Darwin, Woodward, and Perry, on the physical 

 side, have caused them to concede at least 100,000,000 of years 

 as a likely time-minimum. In this they have agreed TNdth 

 the earlier claims of geologists, who aUke from the geodynamical 

 and the palseontological standpoints claimed a greatly extended 

 period. 



From the geological standpoint J. Joly {10: 23) has esti- 

 mated the amount of sodium annually carried to the ocean, 

 since its earliest formation, in relation to the total quantity 

 dissolved there, and concludes that the process of transfer 

 has proceeded for 90 to 100 millions of years. Sollas {11: 24) 

 again is inclined, also on geological grounds, to accept a time 

 limit vaguely intermediate between the minimum and maximum 

 of Kelvin. 



Arldt in treating of the phases of the earth {9: 553) appor- 

 tions the time limits as follows, beginning with the period 

 when the earth had just passed from a nebulous state into that 

 of a white star, and onward till recent date. 



Period of white star evolution 135 millions of years 



yellow star evolution 125 



red star evolution 27^/2 



" " yellow star evolution 125 " " 



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