M>V.\ MOIIV 



efa new geological formation, the Bame thai we have Btudied in | 

 ceding chapters. The structure of Cape Porcupine is represented in 

 Fig. 195. 



Fig. 195. — Arrangement of Syenite, Slate, and ConglomeraU at Cop Fweuj 



<? b a U e 



(a) Syenite. (i) Blate. (c) Conglomerate and Sandal 



At Cape Porcupine the altered rocks of the group now under con- 

 sideration occupy less than throe miles of the coast section, and are 

 separated by Carboniferous rocks and by Chedabncto Bay from the 

 eastern extremity of the older metamorphic district of the Atlantic 

 coast, distant about twenty-four miles. As Cape Porcupine affords 

 bo fossils, and can therefore tell nothing of the condition of the earth 

 and its inhabitants at the time when these slates were deposited, we 

 may proceed to trace the continuation of its rocks into the interior. 



From Cape Porcupine, the southern margin of the metamorphic rocks 

 extends along the northern side of the Carboniferous district of Grnys- 

 borough for about sixty miles, when it meets the Lower Silurian rocks 

 of the coast. In several places along this line, igneous action appears 

 to have continued or to have recurred as late at least as the Coal 

 formation period. This is testified by the condition of the Lower 

 Carboniferous rocks in many places near Guysborougb, westward of 

 which place a considerable promontory of altered and igneous rooks 

 extends to the southward, nearly across the Carboniferous district. 



The northern margin of the band, commencing at Cape Porcupine, 

 may be traced to the westward about forty miles, when it unites with 

 a broader but very irregular promontory of similar rocks extending 

 toward Cape St George. Between these two bands is included the 

 Carboniferous district of Sydney County. The tract formed by their 

 union is the widest extension of these rocks in the province. 



The metamorphic promontory extending to Cape St (ieorge, and 

 including the Antigonish and Merigomish Hills, attain- a greater 

 elevation than the band connected with Cape Porcupine. At its ex- 

 tremity, however, it becomes divided into a number of detached hills 

 and ridges, separated by Lower Carboniferous beds, to which in some 

 eases the metamorphic action has extended itself. The Antigonish 

 and Merigomish Hills contain large masses of syenite, porphyry, 

 compact felspar, and greenstone, associated with slates and quartzil 

 On their western side, near Arisaig, there is a patch of .-hale, slate, 



 Quartzite is a iiinty rook produced by the hardening and alteration ofaandstone. 



