NORTHWEST SHORE OF LAKE SUPERIOR. 361 
At the point, the felspar rock seems to have been protruded through greenstone, as 
shown in the following figure. 
a, Felspar rock. b, b. Greenstone. 
The immense fragments contained in the trap rock, some of which would weigh 
many tons, do not, in any way, influence the direction of the columns. The felspar 
rock, which is very abundant in this neighbourhood, forming large domes, and the 
tops of the highest peaks, appears, at some localities, to graduate into syenite and 
greenstone, by the addition of the proper minerals. The horizontal prisms alluded 
to above, are shown in the annexed figure. 
"a. Prismatic dike. b. Felspar rock. c. Breccia. 
The dike to which they belong, as it proceeds northeasterly, also contains large 
masses of felspar rock, as well as fragments of greenstone and siliceous porphyry, 
and where it is seen on the east side of the point, the columns are vertical. 
The greatest confusion prevails in the bedded rocks at this place, and as far as 
the mouth of Little Cedar River. In the bay, above the point spoken of last, the 
following section occurs : 
a. No. 299. 
Ra JF. Metamorphosed siliceous 
c. No. 301. shales. 
d. No. 302. g- Felspar and quartz rock. 
e. No. 303. 
Ist, The lower beds are metamorphosed siliceous shale (No. 299); 2d, con- 
glomerate, associated with beds of altered shaly sandstone (No. 300); 3d, a. ba- 
saltic bed (No. 301); 4th, highly metamorphosed siliceous shale (No. 302); 5th, a 
bed of greenstone (No. 303); 6th, metamorphosed siliceous shale, in contact with 
felspar and quartz rock, and resembling the rock of the Palisades. 
The eastern side of the bay, beyond the point where the great fragments occur 
embedded in the trap, is made by syenite (No. 622), and beyond this comes a heavy 
dike of No. 613, which seems to bear a little east of north. It is jointed, the joints 
being nearly perpendicular and nearly horizontal, and on weathered surfaces pre- 
sents a singularly mottled appearance. The shore of the next bay is made, princi- 
46 
