SOUTH SHORE OF LAKE SUPERIOR. 269 
crystalline rocks are embedded in the upper stratum. This is the character of the 
shore to the mouth of Bois Brulé River. The preceding section of a bluff, about 
half a mile above Cranberry Bay, will convey a correct idea of the disposition of the 
more recent deposits overlying the sandstone. 
The prevailing colour of the sandstone on the south shore is red, but at many 
points the lower beds are drab-coloured ; and there are frequent alternations of red, 
white, and drab-coloured layers. Some of the beds resemble the sandstones of the 
Chippewa, St. Croix, and Kettle Rivers. Many of the beds in this whole region 
are pebbly, and frequently contain such numbers of large pebbles as to give them 
the character of a conglomerate. The lower stratum in the vicinity of the above 
section is of considerable thickness, and in the upper part contains numerous large, 
round, smooth pebbles, and among them many of a reddish-coloured quartzose por- 
phyry, from two to three inches in diameter. Above this are thin strata of shaly 
sandstone, generally very coarse-grained, and even pebbly, with numerous white 
stripes and spots. Sometimes thin seams of slightly coherent pebbles, small and 
rounded, are interposed between the beds. In general, these rocks are very loosely 
cemented, and when exposed to the weather, soon disintegrate. 
The following section occurs about three hundred yards above the mouth of Cran- 
berry River, and is given here for future reference, when the metamorphosed beds 
north of the Lake come to be considered. 
Feet. Inches. 
ie 
. The lowest stratum is exposed seven feet above the present level of 
the Lake, and is composed of a rather coarse-grained red sand, with 
buff-coloured stripes traversing it, from one to three inches thick. The 
upper part is banded by red and white stripes, from one-fourth to half 
an inch in thickness, marking lines of deposition, which dip about 12° 
to the reverse of the general dip of the rock; while other lines, above 
these, dip in the same direction at an angle of 45°. (The general dip 
of the rocks in this section is southeast from 3° to 4°), : ; 
- Red sandstone, rather more compact, but soft, coarse, and easily 
affected by the weather, 5 : : ; : : 3 
A very coarse, dark red, sandy shale, extremely soft and decomposable, 4 8 ; 
. Sandstone—yellowish red in the lower part, red in the upper, compact 
in some places, but soft and shaly-like in others, ; ; ; 
. Alternations of compact and shaly layers, ; ‘ : ; 
. Sandstone—partly compact and partly shaly, showing numerous cross 
lines of deposition ; weathers easily ; full of small, irregular, roundish 
spots of a yellow colour; much broken by joints. The upper surface 
of this bed contains large pebbles of rounded quartz and trap rocks, . 5 4 
. Red sandstone—rather compact; overhangs the lower beds in the 
escarpments ; the edges are sharper, and the angles better defined, . 3 
. Red clay, ; : : ; : i 16 
. Sandy marl, . : ; 10 
i © i) 
op On 
+I 
ow 
The marl-beds increase in thickness as you recede from the shore. In a small 
ravine, about three hundred yards distant from the Lake, the clay and marl-beds 
measured fifty-eight feet. 
Few of the beds exposed in the escarpments along the shore can be traced for 
