GEOLOGY OF T^IE CONNECTICUT VALLEY DISTRICT, 46 1 



rocks as a separate formation, it would seem to me most advantageous for the science 

 to use the term Cambrian for this purpose, as has ahxady been done by eminent geolo- 

 gists, and as I propose to do on the present occasion. 



" The Cambrian SystExM. In studying the various geological formations which pre- 

 sent themselves in Canada, it is impossible to avoid comparing their architecture, lithol- 

 ogy, and mineral contents with the same or similar formations in European countries. 

 Any one who has had an opportunity of observing them will at once perceive that not 

 only do the Dovrefjeld slates resemble our eastern townships rocks, but also that the 

 primitive and transition rocks of Saxony have much in common with them. Moreover, 

 in examining the manner in which the eastern townships rocks succeed each other, the 

 analogous order of the schists of the Erzgebirge at once presents itself to the mind, 

 and suggests ideas as to the respective ages of the corresponding rocks in Canada. 



" When the traveller in the Saxon Erzgebirge mounts the steep escarpment which 

 borders that range of mountains towards Bohemia, passes northward up the valley of 

 Joachimsthal, and stands at last on the ridge overlooking to the south the valley of the 

 Eger, with Carlsbad in the distance, he has entered the primitive region of Saxony, 

 rendered classical in geology by the labors of Werner and his successors. If the jour- 

 ney is continued northward, by Annaberg, Elterlein, and Lossnitz, to Stollberg, gneiss, 

 mica schist, and clay slate formations are passed over successively, and at last une- 

 quivocal sedimentary and fossiliferous formations arrived at. The order of succession 

 of these schists of Saxony afforded the foundation for the law, long ago propounded by 

 Werner, that mica schist forms the lower, and clay slate or its substitutes, chlorite and 

 talc schist, the upper part of the Urscldcfcr. Further, since the mica schist, in those 

 districts where the primitive formations are present in all their completeness, is found 

 to be supported by gneiss, it follows that in the architecture of these oldest rocks the 

 three groups of gneissic, micaceous, and argillaceous schists succeed each other in 

 ascending order. It must not, of course, be forgotten that in some instances one or the 

 other of these groups may be absent ; — those which are present, however, always show 

 the order of succession here indicated.* This is observed not only in the Erzgebirge, 

 but also in the Fichtelgebirge, the Siideten, the Riesengebirge, Scotland, Ireland, 

 Norway, and Hungary. 



" Turning now to south-eastern Quebec and the states adjoining it, we find that fol- 

 lowing the line of the Grand Trunk Railway north-westward, the succession of primi- 

 tive and even transition strata occurring in the Saxon Erzgebirge is repeated. After 

 leaving the granite and gneiss of New Hampshire, we cross the mica schist district of 

 Compton county, and then chlorite and clay slates from Sherbrooke to Richmond. 

 From the latter place, through the townships of Durham, Acton, and Upton, green and 

 grayish slates, graphitic slates, grauwacke sandstone, and gray limestone, in strata more 

 or less highly inclined, are traversed. All this time the country becomes less and less 

 hilly, the rocks less and less frequent, until near Britannia mills, or, still keeping in a 



* Naumann, Geo^noz:e, ii, 155. 



