tfNSTRA.TIFIED ROCKS. 223 
northern section of New- York as far to the north- 
west as the St. Lawrence river, consists of primary 
rocks, with the exceptions we have already pointed 
out, and shall more particularly describe under Sec^ 
ondary Rocks. 
Primary rocks also compose a principal part of 
the materials of the range called the Ozark Mount- 
ains, west of the Mississippi ; and far off on the 
western side of the continent, in the vast chain of 
the Rocky Mountains, they exist in promiscuous 
profusion, constituting far grander phenomena than 
belong to any part of the range skirting the Atlan- 
tic. Extending far to the northwest, we then trace 
the primitive range, in the shape of low hills, with 
rounded summits, and more or less precipitous sides, 
across the continent to the shores of Lake Superior, 
forming a belt of about 200 miles in width. 
Unstraiified Rocks, — The greater portion of the 
primary rocks of the Eastern States belong to the 
stratified class, such as gneiss^ mica slate, &c., and 
those of the Middle and Southern States consist of 
this class exclusively. The unstratified rocks of 
the United States occur chiefly in the country east 
of the Hudson River, and, as we have already stated, 
may be included under four varieties, viz., granite, 
syenite, porphyry, and greenstone. These are dis- 
tributed in numerous isolated patches among the 
stratified rocks throughout the whole of the New- 
England States, but particularly in the eastern part 
of Massachusetts and in the vicinity of Boston, 
where they occupy more than half the surface. 
They also stretch up along each side of the Con- 
necticut River, at a distance of from 5 to 20 miles, 
enclosing the new red sandstone, and giving pecu- 
liar features to this beautiful portion of country. 
The granite of New-England is thus distributed in 
such irregular patches and so many isolated ranges, 
that it is impossible, within the compass of a work 
like this, to give anything like a correct delineation 
