General Description of Lake Erie. 373 



The situation in the geological series of the fixed rocks of 

 Lake Erie (limestones and sandstone) is doubtful at the south- 

 west end, and unexamined in the centre — between Presqu'isle 

 and Sandusky ; but at the north-east end of the lake, it has 

 been well ascertained. The chasm of the river Niagara lays 

 bare their connection with the saliferous sandstones below; 

 and the State of New York continues the development down 

 to the primitive rocks at the east end of Lake Ontario. These 

 strata are in succession from above, as follows : — 



Calcareous Shale (pyritous) Lakes Erie and Cayuga. 



Comitiferous Limestone Erie and River Niagara. 



Geodiferous Limestone {^'ontariof^*™ '""' ^''^^ 



^EatonT'''^^™'.^'!*^ ^" ^'''"^^'■°"''' °[ jNiagara, Genesee, Lockport. 

 Ferriferous and Saliferous Sandstone . . Niagara, Genesee, &c. 



Millstone Grit (Eaton) L ake Ontario, near Utica,&c. 



Metalliferous Greywacke (Eaton) . . . Ditto. 



Carboniferous Limestone (Metalliferous of i ^^^^ ^^^ ^^ j^ake Ontario. 



Jiaton) J 



WhiteSandstone and Conglomerate Quartz iNorth-east end of LakeOn- 

 and Calcareous .... I tario, and its outlet. 



While the gneiss supporting these rocks, wherever I have 

 seen it, is at an high angle, they are very nearly horizontal ; 

 inclining from the nearest primitive ranges, so as to allow them 

 to appear in succession, at intervals, in the lakes and their 

 vicinity at the same level, the oldest being on the east and 

 north, and the newest in the opposite quarters. Their extent 

 south and west are at present quite unknown. They are spread 

 out in close contact (many, if not all, passing into each other) 

 in very slightly concave layers of vast superficial dimensions, 

 but of comparatively small thickness. It is probable that on 

 the north of Lake Erie the strata dip south-easterly from the 

 apparently greater elevation of the salt-rocks of that lake above 

 those of Ontario. It is almost certain that all these strata un- 

 derlay both these lakes, and Iheir intervening isthmus ; for 

 although the salt rocks have not yet been seen on the north, nu- 

 merous brine-springs sufficiently attest their presence. 



The newest rock in Lake Erie is the shale placed at the head 

 of the above fist. It has been noticed by Mr. Amos Eaton, and 



