52 



in the rock wall is very broad, and in the centre is a mass of 

 shale completely separated from the main hank, and rising 

 like the sea-stacks of the English and Scottish coast from 

 the general platform of rock, which forms the bed of both 

 the stream and the lake. The illustration given below — 

 (Plate XVII.), represents the stack as it appeared in 1888. 

 The dead tree at its further end has long since fallen, 

 through the continued crumbling of the rock, as will be 

 noticed in the photograph reproduced in Plate XVIII. A 

 reference to Plate V. of the Report on the Geology of the 4-th 

 District will show that these conditions did not exist in 

 1843. Only a single mouth is indicated for Pike Creek, 

 which is the opening shown in the right of the illustration 

 (Plate XVII.). The other and smaller one between the 

 stack and the main bank was cut, according to the testi- 

 mony of the residents, within the last thirty or forty years. 



In the ravine of Pike Creek, the Genesee shales alone are 

 exposed, the bed of the stream furnishing a good opportunitv 

 for the exploration of these strata. For some distance be- 

 yond Pike Creek, the Genesee shales form the top of the cliff. 

 Farther on, the gray Xaples ( Cashaqua ) shales appear 

 again in the cliff, rising to a height of about fifty feet. The 

 Genesee shales disappear. below water level about two miles 

 south of the mouth of Eighteen Mile Creek. Before the 

 section comes to an end, the black Xaples (Gardeau) shales 

 again make their appearance, the Cashaqua shales dipping 

 below the water near the end of the section. 



Several of the projecting points of this portion of the cliff 

 can not be rounded by the pedestrian on the beach, unless he 

 is willing to wade in water sometimes waist-deep. These 

 projecting headlands afford interesting examples of the 

 carving and undercutting action of the waves, which, 

 during storms, hurl pebbles against the foot of the cliff. 

 The smooth, cavernous indentations are excellent illustra- 

 tions of phenomena frequently noted on a larger scale, on 



