RECORDS MADL BY RIVHRS AND LAKES 



wide valleys; or valleys which have all the appearance of river 

 vallcvs may have no streams in them at all. In places beds of 

 rounded gravel are lett to mark the channels of departed 

 streams; in other places rocky ledges show that they have 

 been scoured by tools carried by rushing river waters. In a 

 word, major streams in a glaciated region do not conform to 

 any pattern; their courses are determined by the manner of 

 deposition of the drift-cover rather than primarily by the 

 slope of the land and the character of the bed-rock surface. 

 Actually, many of the streams once flowed in directions op- 

 posite to the courses they now take, as, for example, Maumee 

 River which now enters Lake Erie at Toledo: its drainage 

 pattern is more like a double anchor than like a tree; its val- 

 ley widens toward the headwaters which once flowed south- 

 westward down the channel of the Wabash. A dry river 

 channel now separates the Wabash and the Maumee near 

 Fort Wayne, Indiana — a channel which has its place in the 

 history of the Great Lakes, as well as in the history of the 

 migrating Indians who used it as a trail and of the white men 

 who there built a fort to guard the way to the west. The life 

 story of most of the streams entering the Great Lakes is as 

 varied as is the tale of the lakes. 



Present-day lakes are making shore lines, beaches, strands 

 and ridges; waves and currents wash sediments onto and along 

 their shores; deltas are being built at the mouths of streams, 

 or the mouths are being filled by wave and current action 

 which curves the lake beaches into them; sands along the 

 shores are rounded and etched to grains of distinctive charac- 

 ter and are sorted and piled by the wind into heaps called 

 dunes; pebbles shifted along the shores by currents and waves 

 become flattened, showing their beach origin in contrast to 

 the rounded pebbles shaped by rolling along in streams. (Such 

 flattened pebbles on a beach are known as shingle.) The 



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