48 071 the occurrence of Freshwater Shells 



Penetanguishene, will serve to show the manner in which the soil has 

 been removed from the side hill and deposited in a position formerly 

 under water, by the continued mechanical action of the waves. Not 

 only does the peculiar stratification of the lower part of the terrace con- 

 firm the supposition that it was deposited on the shore of an ancient 

 lake, but the fact that such excavations have been made in this land- 

 locked position, where the waves could never have had much force, 

 goes far to prove that the lake stood for a long period at this high level, 



" Another ancient beach mark about 15 miles inland, and as far as yet 

 ascertained, about the same level as the one at Penetanguishene, can 

 be traced for a long distance in the township Tosorontio. It passes 

 through the tract of burnt land already described, the soil of which be- 

 ing pure sand, in all probability formed the shoals of a lake extending 

 to the north and east, the outline of which is approximated by the dot- 

 ted line* marked from 70 to 80 feet high on the accompanying map. Nor 

 are these the only traces of old lake beaches met with in this region, 

 although the dense forest nearly everywhere covering the surface is a 

 great impediment to their easy discovery. In the Township of St. Vin- 

 cent, near the village of Meaford, besides a very conspicuous one, cor- 

 responding in level with those already mentioned, several others of 

 lesser note are found at various heights ; at Owen Sound, also, they are 

 remarkably well defined ; while Cape Croker, on the western side of 

 Georgian Bay, viewed even from a distance and the well remembered 

 shape of the Giant's Tomb, on the eastern, show striking evidences of 

 having been acted on for ages by the storms of Lake Huron, when at a 

 higher level. 



" It has been said that some of these terraces are estimated at 70 or 

 80 feet feet above the level of the lake ; by drawing a contour line co- 

 inciding with this height around the lower part of the valley, it is found 

 that the high ridge of sand now in some parts blown up into dunes 

 near the mouth of the River (Nottawasaga), will form a narrow neck of 

 land (supposing the lake at its former level), stretching across from 

 shore 'to shore, and resembling in many respects the "Burlington 

 Beach," on Lake Ontario, and also " Fond-du-Lac," on Lake Superior ; 

 like the first it encloses a bay of considerable depth of water, but of 

 far greater area. That this ridge has been formed in a manner precisely 

 similar to those two, by the sand washed from the adjoining shores, 

 there is great probability, in fact there is good reason to believe that 

 the same natural agents, at present in active operation moving the out- 

 let of the river eastward, have also formed this upper ridge by trans- 

 porting the materials of which it is composed, from the base of the es- 

 carpment in CoUmgwood. 



" In attempting to arrive at the geological age of these ancient 

 beaches, it will be necessary to show whether their position, at a consi- 



* This line encloses a subtriangular space, having one corner in the 

 north of Nottawasaga, another in the centre of Essa, and the third in 

 the north-east corner of Vespra. 



