ESKERS IN THE VICINITY OF ROCHESTER, NEW YORK. 207 



been mapped in so great detail, but it is felt that the results obtained 

 amply repay the greater effort required. 



Rush eskcr. Figure 5, plate XL On going by train from 

 Rochester to Rochester Junction on the Lehigh Valley railroad, one 

 passes close beside this esker throughout its entire length, it being 

 distinctly visible from the car windows. The esker makes its ap- 

 pearance one and one-half miles south of Henrietta on the west side 

 of the railroad and continues in a more or less interrupted course 

 until its termination is reached where the railroad turns southeast 

 for the straight stretch into Rochester Junction. 



The direction of the esker is nearly north and south in con- 

 formity with the direction of ice movement in this locality. 



It varies in height from 5 to 25 feet, the greater part of its 

 course being below 20 feet in elevation so that its representation on 

 the Rochester quadrangle fails to portray its true linear proportions. 



It rises from swampy ground at its origin and pursues a course 

 southward along the swampy forested bottom of a narrow valley 

 that is flanked on either side by drumlins. The northern portion of 

 the esker from its point of origin to the small station called Cedar 

 Swamp is composed of isolated mounds not more than 2 or 3 rods 

 long or more than 10 feet high. From Cedar Swamp southward the 

 ridge is fairly continuous for a distance of about 1^ miles. There 

 are interruptions in its course, creeks wind across, in places it fades 

 out and disappears, however, the places of discontinuity are few and 

 widely separated. Throughout this distance the crest is compara- 

 tively even, interrupted in but few places by low knolls. Its course 

 is of the winding, serpentine character peculiar to eskers. 



This part of the esker terminates in a kame area. From these 

 kames a well defined ridge trends southward a short distance and 

 then divides to form a complex of interlacing ridges, with steep 

 slopes and stony surfaces, enclosing numerous kettles. The accom- 

 panying figure illustrates these conditions and indicates further that 

 streams have succeeded in crossing this complex in two places. The 

 terminal portion of the esker south of the reticulated complex con- 

 sists- of three distinct ridges, the one toward the west having a large 

 kame extending from its western flank. These three ridges end in a 

 kame topography which ceases abruptly southward at the margin of 



