76 FORESTRY IN EASTERN RUSSIA. 



flank of the mountains, and not a particle of it into the low 

 country of Siberia, it follows that by far the greatest varia- 

 tion in physical outline which the region has undergone — 

 one by which a lofty wall was thrown up between Permia 

 and the orginal copper-sites of the Ural range — took 

 place at a period posterior to the formation of the Permian 

 deposits." ' 



