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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 9, 



mouth of the Black River, the gritty deposit overlooks the water in 

 two lofty stairs or embankments ; hut to the east of the river the 

 plain lowers in a succession of banks, six in number, except in places 

 where from occasional coalescence they become fewer. 



Close to the river's mouth, on the east, all the stairs or ledges 

 have been swept away, and are lost in one great concave of 1300- 

 1500 yards' chord, facing both river and lake. This feature arrests 

 the traveller's eye instantly, and is well represented in Prof. Agassiz's 

 late work on Lake Superior*. 



I saw no means of ascertaining any differences as to the time and 

 mode of deposition. There may be stratification, but I saw none ; and 

 neither Prof. Agassiz nor Mr. Logan mentions any. I therefore take 

 these deposits to belong to one long epoch, from their materials being 

 always in the same splintered or pounded state ; and from their being 

 in such large quantity. A few miles east of this (thirty-four miles 

 W.N.W. from Peek River), we find a bay whose shore rises 20 feet 

 by four ledges of rounded pebbles. These are surmounted by two 

 banks of sand and gravel ; the first rising at an angle of 50° to the 

 height of 25 feet ; and the second to the height of 40 feet, — with a 

 terrace on the top, therefore, of 85 feet elevation. 



The shores fourteen miles east of the Otter's Head, and for twenty 

 or thirty miles hereabout, present many high banks of this sort ;— the 

 materials are native. 



At the mouth of the Michipicoton River are extensive ranges of 

 sand-hills, of which one near the fort is 60 feet high, and is composed 

 of stratified sand and gravel f . 



At Cape Choyye Prof. Agassiz found a beach with five terraces ; 

 the lowest one falling steeply into the water some 20 feet, showing 

 that it alone can be connected with the present level of the lake, 

 and the rest must belong to former epochs J. 



Twelve miles south of Gargantua commence a series of deep and 

 extensive deposits of white siliceous or granitic sand, reaching to the 

 northern angle of Huggewong Bay (seventeen miles) . White granite 

 prevails here. 



The bottom of this bay is faced with sand-banks, which retire in 

 successive terraces a mile or two inland, and are lost to sight from 

 the lake. 



The outer half of its south shore presents the same appearances ; 

 but here the sand is intermingled with large and small boulders of 

 the rock of the district (fine-grained white granite), — not always in 

 confusion, but often in horizontal layers. These banks, 10-30 feet 

 high, run out of sight behind the adjacent hills. 



Of the interval between Montreal River (where we have now ar- 

 rived) and St. Mary's River, it will suffice to say, that wherever a 

 cove or bay occurs, while the points are armed with fixed rocks, the 

 inner shores are gravel- or sand-banks, from 5 to 30 feet high ; the 

 latter always much mixed with boulders, and passing into the rear 



* Lake Superior, its Physical Character, Vegetation, and Animals, by Louis 

 Agassiz ; with a Narrative of the Tour, by J. Elliot Cabot, &c. 8vo. Boston, 1850. 

 t Agassiz, loc. cit. p. 60. % Loc. cit. p. 57. 



