Barre moraine. 697 



less than 5 miles, a difiference which seems too great to he diie to uplift. 

 Uplift here may amount to a foot or more per mile along a line from south- 

 west to northeast, as shown by measurements on the neighl^oring portion of 

 the beach of Lake Warren. A variation of 10 to 12 feet ma}' also occur in 

 a shore line, independent of uplift, there being that amount of variation in 

 the beach of Lake Erie. But if these are combined it would cause scarcely 

 half the variation in altitude which this part of the ridge displi'iys. 



TOPOGRAPHY. 



There are few moraines which present greater variations in topography 

 than are displayed by this one. Knobs and basins, smooth till ridges, eskers, 

 drumlinoid forms, and nondescript or irregular forms are all present. 



For a few miles south from Lake Ontario only a few low swells can be 

 detected, but the bowlders which appear in great numbers seem to indicate 

 the position of the ice margin. They occupy a belt 2 miles or more in 

 width, in which they have been heaped in great piles in the fields and built 

 into stone walls. 



On the face of the Niagara escarpment for 2 miles east from the eastern 

 edge of the city of Lockport the moraine consists of a series of knolls and 

 basins, which give that part of the escarpment an appearance strikingly in 

 contrast with the smooth face it presents west from Lockport. From the 

 brow of the escarpment about a mile east of the city limits of Lockport a 

 well-defined ridge 15 to 40 feet in height and one-fourth mile or less in 

 width leads eastward past McNalls and Royalton. Its surface is gently 

 undulating, like the till ridges so common on the plains of Illinois, and, like 

 them, it is composed largely of till. To the north, between tliis ridge and 

 the escarpment, there is a gently undulating tract thickly strewn with 

 bowlders, while along the brow of the escarpment several knolls 15 to 20 

 feet high appear. South of the till ridge the surface is nearly plane as far 

 east as the meridian of McNalls. A system of knolls and ridges there sets 

 in which leads eastward to West Alabama, and which may belong to the 

 Batavia moraine. The ridges are broken by occasional gaps and are some- 

 what disjointed, but are definite for 2 or 3 miles at a stretch, as shown by 

 the topographic map (PI. Ill) In fi)rm they are similar to the ridge that 

 leads through Royalton, but they are also similar to the till ridge southeast 

 of Tonawanda Swamp in Alabama Township, Genesee County, of which 

 they are, perhaps, the continuation. 



