428 DESCRIPTION OF THE COUNTRY BORDERING 
tain, over which the winter trail to Fond du Lac passes. The terraces above the 
red clay are three in number, very abrupt, and well defined. I found the same 
number at about the same elevation at another section three miles north. The 
material of the drift is here almost entirely water-washed boulders, of the trappose, 
quartzose, granitic, and metamorphic rocks of Lake Superior, very large, and with 
little gravel and earth between them. The crests of the terraces have frequently 
the appearance of ledges, and one is every moment in expectation of finding some 
rock in place. I had much difficulty in coming to the conclusion that the boulder 
drift overlies the red clay, the junction is so much mixed and confused. The red 
clay, wherever the sand-rock is visible, rests on it without any intermediate coarse 
materials. The red clay never rises over about two hundred and fifty feet; seldom 
more than one hundred and fifty; while the boulder drift can be found four and 
five hundred feet and more above the Lake; it is therefore evident that the former 
was deposited in part, at least, before the violent action causing the coarse boulder- 
drift commenced. This action may have been contemporaneous with the latest 
stage of the clay deposit, extending over only part of the region, and operating at 
a higher level. . 
The base rocks on which the clay was deposited, rise as you recede from the 
Lake, so that this deposit becomes thinner away from the coast, although its surface 
rises also, but not so fast as the underlying rocks. Currents sufficiently powerful 
to transport boulders, two and three feet in diameter, to the tops of these hills, five 
hundred feet above the Lake, would of course commingle the two classes of de- 
posits, and obliterate the exact line of division. The drift terraces continue south- 
ward from the section around the southern extremity of the mountain, so well 
marked as to be easily counted at the distance of ten miles, in clear weather. They 
are not of equal or of uniform height either way, from the section varying from 
twenty to fifty feet; the last bluff to the summit being from ninety to one hundred 
feet. Still, the impression is very strong on the mind of the beholder, that they 
are ancient beaches or shores; or if they are of submarine occurrence, that they 
have been modified by the temporary action of the waves of the retiring seas. They 
are very nearly horizontal, a circumstance distinguishing them from bars and ridges 
formed beneath the surface. I have nowhere else in this region seen well-defined 
terraces that are consecutive. The clay bluff of which a section is here given, is 
three miles west of Montreal River, and is sixty feet high. 
a. Clay and sand, mixed. 0, Light gray sand. c. Red ductile clay. d, d, d. The mouths of gullies. 
The surface limits of this clay are indicated on the map. It is being reproduced 
at this time over the bottom of the west end of the Lake by the streams, which 
bring down large quantities after every rain, and by the waves, that dislodge and 
carry out from the shore the minuter portions in suspension. Some estimate may 
