Pleistocene Geology of Moravia Quadrangle 393 
silting up of the valley floor. To a less extent this is true of a halt 
immediately south. 
In the Moravia-Freeville valley, where we find the best developed 
valley loops of the sheet, the northward slope that the valley floor 
has, as explained above, hindered the formation of typical valley 
trains. In this connection, however, it should be remembered 
that a valley train having undergone rather active erosion in post- 
Wisconsin times is apt to be so altered as to lose its more definite 
aspects. This valley has been subject to erosion by a north- 
flowing stream during part of the post-Wisconsin interval or at 
least since the high-level lake in it fell below the Lansing outlet; 
the present stream here drops 325 feet in 12 miles, a grade of 27 
feet per mile. 
The level area, which is quite extensive for some distance south 
of Moravia, is partially the product of delta filling that has con- 
stantly followed the receding lake level, and is still in progress 
just north of this sheet. Another interval of fairly level bottom, 
just south, cannot with certainty be explained as entirely of valley- 
train genesis. From Peruville southward, however, where the 
old valley floor doubtless has a southern slope, We may recognize 
the play of ice-front streams aggrading to the extent of produc- 
ing valley trains. This suggestion pertains especially to the ice- 
front drainage characterizing the halt at Peruville. 
The normal conditions for the formation of outwash plains, 
as described by Salisbury,^^ do not exist on the Moravia sheet. 
Nevertheless there is evidence particularly in the vicinity of Free- 
ville where we have a very broad valley bottom, broader still no 
doubt before the kame deposits were made eastward by the 
retreating Wisconsin ice, of the conditions which here favor the 
' coalescence of alluvial fans of ice-stream origin. The great 
masses of kame moraine flanking the Freeville-Cortland valley 
represent a duration of ice-debris accumulation that must have been 
attended by heavily burdened streams flowing away from the Free- 
ville area. The Junior Republic kames, however, were formed 
I when the ice obstructed the drainage, thus ponding a lake which 
I extended southward overflowing south of Dryden lake; so long 
as ice blocked the ponded water from escaping westward through 
I Fall Creek valley, outwash gravels developed only as fans into 
GeoL Surv. of New Jersey, vol. v (1902), pp. 128-9. 
