OF UPPER CANADA AND THE WESTERN PART OF OHIO. 275 



of the main terrace, while the red shales and sandstones still lower in the series 

 overspread the plain which stretches northwards, from the margin of this bench 

 to the Lake shore; the whole of this series of strata, from the red shales up- 

 wards, having a gentle dip towards the south. 



In passing from the Niagara river to the head of the Lake, we remarked a 

 gradual but slight change in the lithological character of some of the strata of 

 the Niagara limestone, the nature and degree of which will be best indicated by 

 the annexed sketch of a vertical section of these rocks, as they are displayed 

 in the mountain ridge at a point west of Hamilton, and upwards of fifty miles 

 west of the Niagara river. 



Section West of Hamilton on the Road to Ancaster, in the descending 



ORDER. 



L Brownish, subcrystalline, bituminous limestone. 



2. Siliceous limestone of a brownish and gray colour, containing distinct 

 courses of flint or cherty nodules. 



3. Rather soft siliceous sandstone, occurring in thick slabs. 



4. Hard siliceous limestones and sandstones with the vesicular structure, 

 and hollow encrinal impressions characteristic of similar strata at Niagara 

 Falls. 



5. Lead-coloured shales and calcareous slates. 



Comparing the above series of strata, in detail, with a section of the rocks 

 at the falls and whirlpool, obtained by repeated examinations, we find that 

 while the general character and order of succession of the principal beds remain 

 unaltered, the calcareous and siliceous portions are more defined in their com- 

 position, the geodes are much less frequent in all the beds, and the cherty 

 matter of the higher strata is more entirely collected into regular layers or 

 courses. The whole group is also considerably thicker than on the Niagara 

 river. 



For some distance westward of the escarpment of these rocks, the upper 

 plain formed by the mountain ridge is in general deeply covered with drift 

 composed of the rolled fragments of the siliceous and bituminous limestones 

 and sandstones, together with some of the materials of the red shale and sand- 

 stone of the formation next below; but almost entirely unmixed with the frag- 

 ments of other higher calcareous rocks. Between Ancaster and Brand tsford, 

 viii — 3 u 



