244 ROLLIN T. CHAMBERLIN 



roughly established with the ice-front six or seven miles farther west, 

 where the St. Croix moraine was piled up. This belt appears on the 

 quadrangle about midway of the north margin, from which point 

 it runs nearly straight south for ten miles to Dresser Junction, where 

 it is cut in two by a gap. Beyond the gap it continues south for four 

 miles, and then, as a much narrower strip, turns southwest, becoming 

 wider in the extreme southwest part of the quadrangle. (See map.) 

 In width, the belt varies from three miles in the northern portion, to 

 about half a mile in the Township of Farmington. Like the older 

 moraine, its concave side faces west-northwest. It is exceedingly 

 rough and choppy, abounding in hummocks and kettles, knobby 

 ridges, and blind valley depressions, the whole heavily overgrown 

 with small trees and underbrush. The noticeably different aspect 

 of the ridge when approached from the east and from the west is 

 worthy of mention. On its eastern side the moraine merges into a 

 smooth plain dipping gently away from it. There is no steep descent, 

 nor are the moraine hills very much higher than the plain. On 

 the west side, however, a steep declivity along the entire edge of the 

 belt gives it an abrupt, ridge-like appearance. The hills in many 

 places rise 200 feet above the lowland to the west. The significance 

 of this marked difference will be readily understood in connection 

 with the formation of the moraine and its outwash plain toward the 

 east. 



The St. Croix outwash plain. — Most of the region between the 

 St. Croix and Alden moraines, with the exception of some hills of 

 ground moraine which stand up above it, and an area near East 

 and Horse Lakes which was never covered by outwash, belongs to 

 the St. Croix outwash plain. With an altitude steadily diminishing 

 to the east and southeast, the plain fades out in the neighborhood of 

 the Alden terminal. East of Long Lake it reaches, and has even 

 buried, some of the lower slopes of this ridge, over six miles from 

 the ice-front at the St. Croix stage. But in general, east of the edge 

 of the map, the outwash development is weak, and the underlying 

 ground-moraine topography becomes more and more pronounced. 

 The smoothness of this gravel plain, its rise near the crest of the 

 moraine, its gentle slope to the eastward, and its mergence into 

 drainage tracts in that direction, furnish the grounds for my inter- 



