No. 1.] GIBSON — GEOEOGY OF HURON COUNTY. 35 



Indian traders — a name which was probably given it from the 

 color of its waters, which, although perfectly transparent, are 

 generally of a reddish-brown tint. The Indian name for the 

 river is Mcncsetimg. Near its mouth the stream is broad, and 

 its bed is composed of course gravel and sand, underneath which 

 a moderately thick stratum of peat has recently been discovered ; 

 but, after ascending it for a few miles, the channel becomes con- 

 tracted, forming as it were a ravine-like basin, denuded by the 

 action of its waters in the limestone fundamental rocks of the 

 locality. The Bayfield River, on the other hand, drains the cen- 

 tral, or rather the more southern portion of the County, and flows 

 into the saiiic waters some twelve or thirteen miles south of the 

 emhoudiure of the Maitland. The only other river of impor- 

 tance is the Riviere aux Sables (South) which forms the south- 

 ern limit of the County. Flowing at first in a north-eastern 

 direction, and bounding the Township of Bosauquet on the east, 

 it makes a bend at its northern extremity, then running nearly 

 parallel with the coast for about ten miles, it enters the Lake. 

 Extending along the western limit of the County, in a north 

 and south direction, lies a remarkable ridge composed of water- 

 worn gravel and fine sand, whose general contour is parallel to 

 the present margin of the Lake. Conforming to the irregularities 

 of the coast for about sixty miles, and at an average distance from 

 it of a mile and a half, it reaches the sandy flat's of the Riviere 

 aux Sables, and is finally lost. The western slope of this lacus- 

 trine terrace inclines gradually towards the present lake beach, 

 and within this limited area, deposits of shell-marl are frequently 

 found. Future researches will no doubt prove the existence of 

 other terraces lying more to the eastward, which will doubtless 

 throw much light on the former physical features of this lake- 

 area. Our terraces are monuments of great geological value, 

 indicating to a certainty the former submergence of our land 

 under the waters of a vast fresh-water inland sea. 



Throughout this tract of country there is ample evidence of 

 denuding forces at work, both prior and subsequent to the Glacial 

 Period. The high clay clifts along the margin of the lake, and 

 the numerous ravines and valleys, which are so conspicuous along 

 the courses of the above-named rivers, afford unmistakable proofs 

 of the former physical conditions of this region. 



The palaeozoic strata of this western portion of Ontario are 

 everywhere covered by the vast accumulations of the Drift Period, 



