THE AGE OF THE EARTH 



By GEORGE F. BECKER 

 CONTENTS 



PAGE 



Introductory Review 1 



Age from Soclium Accumulation 6 



The data 



Increment of oceanic sodium 6 



Results of asymptotic accumulation 11 



Age from Refrigeration 17 



Historical note 17 



Modified problem 19 



Numerical results 24 



Conclusions 27 



INTPtODUCTOEY EEVIEW 



The birtliday of the world known to us is commonly regarded as coin- 

 ciding- with the epoch of Leibnitz's consistentior statvs!^ This great phil- 

 osopher believed that the earth solidified from a state of fusion by stages 

 similar to those he had observed in the refrigeration of large mavsses of. 

 metal : cavities analogous to blow-holes developed and burst ; thin partial 

 crusts formed and broke : in some cases such crusts were extensive enough 

 and sufficiently cool to receive bodies of water, but were not strong enough 

 to support the accumulated liquid and presently gave Avay, so that fresh 

 convulsions ensued. At length, through the progress of refrigeration, 

 the globe emerged into " a state of greater consistency." Then chaos was 

 at an end and permanent oceans became possible. 



It is interesting to note that Leibnitz seems to have had in mind not 

 merely dry fusion, but fusion Avith the co-operation of water, or what 

 would now be called aqueoigneous fusion. 



Three methods have been devised for ascertaining the age of the ocean : 

 one from the accumulation of stratified rocks; another from chemical 

 denudation; and the third from the progress of refrigeration. Closely 

 allied to these is Sir George Darwin's discussion of the lapse of time since 

 the earth and the moon parted company." 



1 Protogaea, 1749. A sketch of this posthumous work .ippeared in the Acta Eruditorum, Jan., 

 1693. 



2 Phil. Trans., London, vol. 170, 1S79, p. .^11; and vol. 171, ISSO, p. S82. 



Smithsonian Miscellaneous Collections, Vol. 56, No. 6 



