﻿240 Canadian Record of Science. 



Black Forest ; then the Harz, and finally the ranges of 

 Bohemia. 



This whole area, like the last, consists of fragments of 

 old, broken-down, folded mountain ranges ; the folds may 

 easily be followed in Vogesen and the Black Forest, and 

 a parallel curve occurs in the Taunus. 



In this broad area two directions of folding may be 

 distinguished : in the w^est the dominating folding is 

 towards the north-east, and in the east a similar one 

 towards the north-west. These two directions of folding 

 meet one another in the middle of the central plateau of 

 France. 



Where the rocks of the Caledonian Mountain system 

 abut against the Hebrides, there are enormous over- 

 thrusts, the strata are turned upside down, older forma- 

 tions being pushed over younger. Phenomena quite similar 

 are found on the northern edge of the second-mentioned 

 series of horsts. 



These inversions are distinctly seen in the Belgian coal 

 measures ; indeed, in many places, they alone determine 

 the boundary between this formation and the Caledonian. 



The great western curve is called the Armorican, 

 because its principal development occurs in Brittany. 

 The highest parts of these ancient mountains were here. 

 The eastern curve is called the Variscian, after the people 

 of Varisca, who once lived in the Vogtland, where moun- 

 tain cores formed of old rocks are found. The most 

 important phenomenon of the whole system, Armorican 

 as well as Variscian, is that the whole palcTozoic series up 

 to the middle carboniferous is included in the folds. 

 Hence this second system of folds and subsidences is 

 somewhat younger than the preceding system of pre- 

 Devonian folds. It includes the Silurian, the Devonian, 

 and a great part of the Carboniferous ; the Belgian coal 

 measures mentioned above have taken part in the 

 movement. 



