174 THE GLACIAL LAKE AGASSIZ. 



or Itasca moraine occupies a width of 5 to 10 miles. Its hills of till, with 

 abundant bowlders, rise 25 to 50 feet above the hollows and frequent lakes, 

 and the elevation of the morainic belt averages 100 to 150 feet above the 

 general level of the country. Following the main watershed omvard, it 

 bends to the northwest and north between Lake Itasca and the source of 

 the Red River, and continues northward past the west side of the Upper 

 Rice Lake to Clearwater Lake, about which it is well developed, and a 

 few miles fiu-ther north it enters the area of Lake Agassiz, some 10 miles 

 southwest of Red Lake. 



The southern border of the Itasca moraine, where it is crossed hj the 

 road from Park Rapids to Lake Itasca, is called Stonj- Ridge. It consists 

 of small ridges of till, trending from southeast to northwest, with very 

 plentiful bowlders, all Archean from the northeast and north, chiefly 

 granite and gneiss. No limestone bowlders were observed there; but in 

 the vicinity of the White Earth Agency and about Red Lake they form 

 a considerable proportion of the drift, ha\'ing been Iw-ought by glacial 

 cun-ents from the region of Lakes Winnipeg and Manitoba. Very irregu- 

 larly grouped morainic hills, 50 to 100 feet high, rise on each side of the 

 road, which winds and climbs and descends over them, along a distance of 

 about 8 miles from Stony Ridge to Mr. Peter Turnbull's claim cabin, on 

 the southeast arm of Lake Itasca. 



Many empty hollows 20 to 40 feet deep are seen beside this road, 

 being kettle-holes, as they are called, well known as characteristic of 

 morainic di-ift deposits. Several similar hollows, Init <:if larger size and 

 greater depth, contain a series of picturesque little lakes, lying east of the 

 road, in descending order from south to north, the lowest having an outlet 

 to Lake Itasca by Mary Creek. These small lakes fill depressions of the 

 di-ift, and Lake Itasca doubtless owes its existence to greater thickness of 

 the cb-ift in the valley at the mouth of the lake and for several miles down 

 the Mississippi, rather than to greater prominence of the underlying rock 

 there. But the great valley, 150 to 200 feet deep and 2 to 4 miles wide, in 

 which lie Lake Itasca and the IMississippi northward t(i Craig's crossing, 

 and to its rapids over bowlders in section 8, township 145, range 35, and 

 the similar but smaller vallevs of the La Salle, Hennepin, and Schoolcraft 



