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vessels to reach the town of Dundas, three miles (4-8 km.) 

 west of Hamilton bay. The old shore of Lake Iroquois 

 can be observed stretching round to Dundas; but its 

 western end is poorly marked in a region of hummocky 

 morainic material where the Ontario lobe of the last ice 

 sheet made its way up an ancient valley cutting the 

 escarpment. Beyond the depression of Dundas bay the 

 escarpment rises in imposing cliffs which turn off to the 

 northeast and after a few miles bend northwards. 



Descending the escarpment one passes first the thick 

 sheet of Niagara limestone (Lockport) then the softer 

 gray shales (Rochester) and reaches the Clinton limestone 

 beds, much thinner than the Niagara limestone above. 

 Below this come the gray Cataract sandstone and the red 

 Richmond or Queenston shale, which underlies the talus 

 near the foot of the escarpment and is largely hidden. 



The slope occupied by the city between this and the shore 

 of Hamilton bay is formed mainly of Iroquois beach 

 deposits, sand and silt, well stratified and often 20 feet 

 (6 m.) or more thick, as shown in excavations. Rarely 

 the red shale may be seen in unusually deep cuttings. 



THE IROQUOIS BEACH AT HAMILTON. 



Descending the escarpment toward the east end 

 of the city one stands upon the Iroquois terrace at the 

 foot of what must have been a fine shore cliff 300 feet 

 (90 m.) high. The old beach can be followed westward 

 for a mile at the foot of the cliff and then bends northwest 

 as a gravel bar through the highest part of the city, passing 

 Dundern park and the cemetery and running nearly north 

 as an extraordinary embankment of sand and gravel, 

 less than a quarter of a mile (-4 km.) wide and 116 feet 

 (35-4 m.) high. The bottom is of sand and the upper 

 66 feet (20-2 m.) of coarse sand and gravel, partly cemented 

 to conglomerate by the deposit of lime between the pebbles. 

 In general the stratification runs horizontally and with 

 great uniformity. At Desjardins canal, an artificial 

 cut across the bar, it is seen in cross section that the 

 materials are often crossbedded. Beyond the canal, 

 which is crossed by railway and road bridges, the bar 

 curves somewhat east of north and ends at the former 

 outlet of the Dundas marsh, now filled in with a railway 

 embankment. The bar evidently pushed out from the 



