338 DESCRIPTION OF THE 
River and the head of Thunder Bay. In other words, the Lake shore has the same 
bearing as the trappous and altered rocks which lie contiguous to it, namely, 
northeasterly and southwesterly. Along almost the whole of this line the shore is 
rockbound ; the rocks rising from the water in escarpments, many of them mural, 
from ten to two hundred feet in height, and presenting an almost unequalled sec- 
tion of igneous and altered rocks. At no points are sloping wooded plains to be 
seen, such as bound the Lake on the south shore at many points in Wisconsin, 
between Fond du Lac Supérieure and Montreal River. 
The shore is indented by numerous small bays and pockets; none of them very 
deep, however, but sufficiently so to afford many valuable sections, which serve to 
show the relations between the igneous and sedimentary rocks. Occasionally, the 
hills rise abruptly from the shore to the height of two or three hundred feet; but, 
generally, after rising from ten to forty feet above the water, there is a gradual 
ascent to the summit of the first ridge, the lower part of the slopes often being 
covered with cedar swamps. The ridges generally increase in height as they recede 
from the shore. The declivities on the lake side are almost always abrupt near the 
top, while on the opposite side the descent is rather gradual from the summit to the 
valley which intervenes between it and the next subordinate ridge. Through these 
valleys, which are often little more than ravines, the streams which drain the 
country between the Lake and the summit-level, wind their way; running, some- 
times for long distances, in the line of bearing of the rocks, and at others intersect- 
ing the ridges in their course. At the same relative distance from the lake-shore, 
the height of the ridges is about the same; the highest measured by me being a 
little over nine hundred feet above the lake-level, and between four and five miles 
in a direct line from the Lake. As a general thing, the subordinate ridges are short, 
with abrupt terminations, and vary considerably in height. This gives to the ranges 
a peculiar, broken, craggy outline, which contrasts forcibly with the hills of granitic 
and schistose rocks met with still further north, and which are more or less regu- 
larly rounded. 
At the bottom of many of the bays, the beach is low, and covered with boulders, 
derived not only from the neighbouring rocks, but also, and probably in greatest 
proportion, from the granitic rocks which lie to the north. The boulders, by the 
conjoined influence of storms and ice, are frequently heaped up along the beach of 
the small bays, at the distance of fifty or one hundred yards from the water, to the 
height of eight or ten feet above the lake-level, like barriers; the intermediate 
space being occupied by sand and pebbles, among which a great many siliceous 
minerals are found, as, different varieties of quartz, agate, carnelian, chalcedony, and 
jasper. The beaches are rarely more than one or two hundred yards in length, and 
can only be approached by canoes or other very small craft. At several points, 
however, boats of considerable size could effect a landing, and, in several of the 
small bays, remain sheltered from storms. Near the shore the water is generally 
shallow, and deepens as you advance into the lake, in conformity, apparently, with 
the dip of the rocks which bind the shore at each particular place. As the eastern 
part of the District is approached, the bays become deeper, and often narrow, and 
are bounded by high mural walls of rock, which, in one or two instances, rise to the 
