200 TOWARDS THE HUMAN FORM 



may exceed 10,000 metres in thickness, but these have been 

 violently folded and eroded. All that remains to-day is that 

 portion of these colossal folds directed inwards into the 

 earth's surface where the heat generated lateral pressure at 

 the time of the folding, and the resistance of the still older 

 formations beneath to penetration by the edges of the folds, 

 was so intense that all the matter deposited by the 

 waters became dissolved or molten, and was regrouped 

 in crystalline mineral formation ; quartz, felspar, pyroxene, 

 mica, and amphiboles, whose association first produced 

 the mica-schists, then gneiss, and leptynites whose primitive 

 stratification is still discernible, and finally, the granites, 

 amphibolites, and unstratified porphyry, in which occur 

 isolated minerals such as garnets, tourmalines, emeralds, 

 and other hard stones. We could not expect to find in deposits 

 so completely metamorphosed, as the geologists say, the re- 

 mains of delicate primitive Algae. However, in Finland, the 

 oldest of these formations, the Archcean, contains carbonized 

 matter and specks of a special kind of lime called cipolin. We 

 may feel pretty sure that lime and organic matter found in 

 sedimentary deposits are all of organic origin. Hence there 

 must have been living organisms even at that remote epoch, 

 which was long known as the Azoic, because it was supposed to 

 correspond to an era in which the first consolidation of the 

 earth's crust took place, when life did not yet exist. A Scandi- 

 navian naturalist, J. J. Sederholm, has even found in it the 

 remains of organisms, but they are so ambiguous that some 

 have regarded them as plants, others as Echinoderms. 



Furthermore, the existence of living organisms on the earth 

 during the Archaean Period is rendered highly probable by the 

 discovery of a variety of fossils in the Algonkian strata which 

 follow next, and are essentially formed of mica-schists, and 

 for a long time were also regarded as azoic. No plants have 

 been discovered here, nor yet in the Cambrian Deposits which 

 initiated the series belonging to the Primary Epoch, and which 

 at times attain a thickness of 3,000 metres. However, it should 

 be remembered that at Shunga, in the Government of Olonetz, 

 and at Snojarvi, in Finland, there are intercalated between the 

 layers of Algonkian schists beds of dense coal, presenting 

 here and there a metallic lustre, which are richer in carbon 

 than anthracite and often attain a depth of two metres. 



