82 THE FAR PAST. 



tute of organic remains. So far as our present purpose is 

 concerned, it matters little which term is adopted, so long 

 as we bear in mind that up to the present day they have 

 yielded no traces of life, and are to all intents and purposes 

 truly Azoic. That the Crystalline or Metamorphic strata^ 

 termed clay-slate, mica-schist, and gneiss, were at one time 

 the clayey, sandy, and limy deposits of seas and estuaries, 

 is at once admitted by every competent geologist ; and that 

 if these seas contained life, those strata must have imbedded 

 its remains. But then, these deposits have, since their soli- 

 dification into rock, been subjected to thermal, chemical, 

 electrical, and other agencies, to such a degree that they 

 have been converted, or metamorphosed, into crystalline 

 masses, and every trace of life has been obliterated from 

 their structure. No doubt it has been ingeniously sug- 

 gested that the occurrence in metamorphic rocks of sulphuret 

 of iron, of phosphate of lime, bituminous springs, and other 

 similar products, gives evidence of the presence of organic 

 bodies, through the medium of whose decay such com- 

 pounds were eliminated. On the other hand, experimental- 

 ists equally ingenious have assigned to these products a 

 purely chemical origin ; and, even if they could not, the 

 geologist would be little aided by a contrary hypothesis, so 

 long as he had no trace of organic form or texture to guide 

 him in his deductions. 



To the palaeontologist, therefore, the CAMBRIAN period, 

 with its obscure and scattered zoophytes, trilobites, and 

 shells, becomes the so-called " Dawn of Life." He knows 

 of nothing beyond this primordial zone, and the spirit of 

 true philosophy forbids him to substitute conjecture for 

 fact, or hypothesis for reality. It may gratify the cos- 

 mogonist to fashion a glowing globe by the condensation 

 of nebular masses, to cool by radiation a solid crust on the 

 glowing orb, and, after ages of chaotic confusion, to plant 



