98 PTOceedi'ngs of Indiana Academy of Science 



The land north of the Mt. Summit Moraine slopes to the west and 

 the present drainage is in that direction. After the ice retreated north 

 from this moraine in Randolph and Delaware counties, a dam, presum- 

 ably a part of the ice sheet, still lay to the west and southwest. When 

 this dam of ice melted away a lower outlet was opened up and these 

 four valleys leading southward ceased to carry water from the melting 

 ice. 



After these valleys were abandoned by glacial waters, they received 

 only the run off from short, transverse tributaries flowing from adjacent 

 areas of the moraine. The small volume of water spreading out over 

 the broad valley floors was unable to keep the channels open; and 

 alluvial fans spreading out across the valleys soon converted the valley 

 floors into a series of shallow basins in which thick beds of peat and 

 muck accumulated. In time the postglacial streams to the south of 

 the moraine worked back by headward erosion into these swampy areas, 

 while tributaries of West White River, cutting back southward, came 

 into them from the north. 



Natural drainage was so poorly developed that it was necessary 

 to dig large ditches to conveit these swampy tracts into productive 

 lands. Today these areas of rich black soil yield heavy crops of corn. 



A striking feature of the broad belt of muck land which has been 

 reclaimed by the dredging of Buck Creek and Blue River is the large 

 amount of buried wood in it. In places faxmers have dug up cords of 

 wood closely resembling red cedar and used it for fuel. Large pieces 

 may still be found just beneath the plow soil. Samples of this wood 

 collected by State Forester Deam and the writer are in the Slate 

 Museum at Indianapolis. 



Southwest of Muncie is a valley which seems to have been excavated 

 by a single stream, *ilthough at present two streams occupy it. In 

 the northern part is Bell Creek which flows north into Buck Creek. In 

 the southern part is Fall Creek. Between the two there is a portion of 

 the old valley which is not cut by a stream channel. It is a broad 

 swampy divide. The tributaries of these two streams (not well shown 

 on the map), when studied in reference to the old valley, present some 

 striking features. Since this old valley lies wholly on the northwest, or 

 inner, side of the moraine it is merely mentioned here. It will be de- 

 scribed in a future paper. 



