166 PLEISTOCENE OF INDIANA AND- MICHIGAN. 



em end of James Lake. The main line of discharge for glacial waters appears to have been over 

 the basin occupied by Crooked Lake, for the gravelly plain is continued at the western end of 

 the latter. It passes across the basin of Gage Lake, where it emerges from the main moraine. 

 Gage Lake is bordered on the northeast by another gravel plain, whose surface is 45 feet, by 

 hand level, above the water, and is 25 feet above the surface of the plain along the Crooked Lake 

 outlet. As the depth of water reaches 70 feet the bottom of the basin is 115 feet below the 

 higher gravel plain and 90 feet below the lower plain. Crooked Lake is in a shallower basin, 

 its bed being scarcely 50 feet below the bordering gravel plain at its eastern end. The plain 

 that heads east of Crooked Lake has a sandy gravel and seems not to have been formed by very 

 vigorous drainage. The higher plain that sets in at the east end of Gage Lake carries much 

 cobble and coarse gravel and seems to have, been at the head of a vigorous point of discharge. 



OTJTWASH IN MICHIGAN. 



A gravel plain having an altitude of about 975 feet at the Michigan State line descends 

 northward to about 920 feet at Prairie River, 2 miles south of Bronson. North from Prairie 

 River the plain is shown by the drainage and by barometric determinations made by W. F. 

 Cooper to be a little higher on its eastern than on its western border, being about 940 feet on 

 the east and 920 to 930 feet on the west. The slopes, therefore, seem to support the view that 

 the plain was built up in large part at least by outwash from the Huron-Erie lobe on its eastern 

 side rather than by outwash from the Saginaw lobe, as it receded lengthwise of the plain. The 

 character of material is in harmony with this interpretation, cobble and coarse gravel being 

 more conspicuous on the southeastern edge of the plain than elsewhere. Prairie River finds 

 its source in a large marshy plain that extends up into the moraine about to the State line, and 

 that seems to have been a place of discharge from the ice after the latter had receded a few 

 miles from the position it held while the large gravel plain was forming. 



Another extensive gravel plain heads in the midst of the main moraine of this belt just 

 north of the State line in the southeastern township of Branch County, Mich., and extends 

 northwestward to join the one just described near Coldwater. For 10 miles from its head 

 its average breadth is about 4 miles and its maximum nearly 6 miles. Farther north it is 

 reduced to a width of about a mile and is bordered by distinct bluffs, as if trenched by a stream. 

 The broad gravel plain is not bordered by definite bluffs. The plain has numerous dry basins 

 near its head and farther down it contains several lakes, the largest of which, Coldwater Lake, 

 has an area of about 2 square miles. Considerable cobble and coarse gravel occupies the head 

 of this plain in the vicinity of the hamlet of California, becoming finer northwestward or down 

 the slope of the plain. The altitude at the head of the plain is 1,020 to 1,030 feet, as determined 

 barometrically by W. F. Cooper, but it drops to about 975 feet at the south end of Coldwater 

 Lake, or about 50 feet in 5 or 6 miles. Farther north the descent is more gradual, being only 

 70 feet from Coldwater Lake along the Coldwater Valley to the St. Joseph Valley at Union 

 City, a distance of fully 20 miles. 



From Coldwater Lake a sandy strip 1 to 2 miles wide runs northeastward to Quincy. In 

 it there is a chain of lakes, of which Marble Lake near Quincy is the largest, its area being little 

 less than that of Coldwater Lake. This sandy strip is probably a line of glacial drainage, 

 though at present the water divides about midway of its course, and the altitude seems to be 

 slightly higher toward the northeast than toward Coldwater Lake. From Marble Lake there 

 may have been glacial drainage southwestward through this sandy depression to Coldwater 

 River at Coldwater Lake, and also westward to the same stream near the city of Coldwater. 

 The outwash from Quincy northwestward along the border of the Tekonsha moraine is discussed 

 in connection with that moraine (p. 152). 



