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Flowerpot Island — Bruce peninsula, separating 

 Lake Huron from Georgian bay, 

 represents the unsubmerged edge of the Niagara cuesta: 

 it is topped by the hard dolomitic limestone of the Lockport 

 formation which rises, at one place in the county of Bruce, 

 to a height of 400 feet (122 m.) above the lake. 



Off the north shore of the peninsula are a number of 

 small islands showing interesting residual structures; 

 the chief of these is Flowerpot island, where huge masses of 

 Lockport dolomite resembling giant vases are supported 

 on diminished stalks of the softer underlying formation. 



Cuesta topography, Wingfield basin, Manitoulin island. 



Manitoulin Island. — The Grand Manitoulin island 

 (The island of the Great Spirit) is stratigraphically a 

 continuation of Bruce peninsula. The Niagara cuesta, 

 which extends into the island, differs from the cuesta in 

 the Bruce peninsula in that it approaches much closer to 

 the oldland of the north shore of Lake Huron. In conse- 



