220 



PRIMARY ROCKS. 



gneiss rock of Manhattan Island. These veins pen- 

 etrate only the oldest rocks, the clay slate being 

 the latest in which they are found. The intrusion 

 of these veins seems to have produced very little 

 disturbance in the rocks containing them. 



We meet with the primary rocks as far to the 

 north on this continent as human discovery has 

 yet extended. The Werner Mountains, on the coast 

 of Greenland, which, according to Scortsby, rise to 

 an elevation of 6000 feet, are composed of primitive 

 rock, granite, gneiss, mica slate, hornblende slate, 

 Sic. Primitive rocks also abound on the west coast 

 of Greenland, in connexion, however, with second- 

 ary, tertiary, and alluvial. On the west side of 

 Baffin's Bay, as far as the seventy-fourth degree of 

 north latitude, Captain Parry found the predomina- 

 ting rock to be primitive, and of the same varieties 

 as the preceding. As we come to the south we 

 find the hills bordering on Hudson's Bay, which 

 have an average elevation of about 800 feet, and the 

 highest summits not exceeding 1500 feet, to con- 

 sist chiefly of primitive rocks similar to those al- 

 ready mentioned, and abounding in interesting min- 

 erals, such as zircon, beryl, garnet, actynolite, tremo- 

 lite, rock crystal, asbestos, rhomb spar, iron ore, cocco- 

 lite, graphite, &c. Tracing the country still farther 

 south, along the coast of Labrador and Newfound- 

 land, we still find the primary formations constitu- 

 ting the mountain ranges of Canada, New-Bruns- 

 wick, and Nova Scotia, and bounding the coast 

 through the whole extent of New-England. Indeed, 

 the primary formations occupy nearly the whole 

 area of the New-England States. From their ex- 

 treme eastern boundary they range westward, fol- 

 lowing the St. Lawrence to the lower extremity of 

 Lake Ontario. From that point or at the Thousand 

 Isles, the edge of these formations may be traced in 

 a southeast course to the southern point of Lake 

 George. Farther south than this the western bound- 



