398 THE BIOC08M08 PARTICULARIZED. 



can seek to count the layers of the past, as 

 we do those of the Sequoia. And by such a 

 count we may approximately determine the 

 age of this Earth-life in its multitudinous 

 sequences. The co-odination of all the fos- 

 sils along with their strata around the 

 globe is now a main task of Geology, which 

 has to give at last a telluric chronology, both 

 inorganic and organic up to date. 



The bare outlines of such a chronology we 

 may here set down in the nomenclature usual- 

 ly given : 



(I). Azoic, the era of Unlife, which in the 

 widest sense would embrace the Earth's earli- 

 est appearance in a nebulous form, perchance 

 first in the Cosmosphere, then in the Helio- 

 sphere, then in the Geosphere thrown off 

 from the Sun. This azoic era would include 

 the evolution of the chemical elements, start- 

 ing possibly with proto-hydrogen, which final- 

 ly evolve into chemical compounds, some of 

 which we have with us still in the form of 

 azoic rocks, unstratified, upon which the 

 earliest strata rest and begin the concentric 

 fossiliferous layers of Earth-life already men- 

 tioned. Herewith we have come to the next. 



(TT). Zoic, the era of Life on our globe, to 

 which Life has occurred the transition from 

 Unlife. In this era are found many divisions 

 and sub-divisions, of which the following may 



