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main channel near the northern middle of Section 36. The bed-rock outcrop 
along McCormicks Creek in the southeast part of Section 26 indicates that 
the region to the northeast was high, very probably a divide between the 
tributary just mentioned and the one that undoubtedly came from the 
northeast of section 24. Wells Nos. 10, 11 and 12, by their depth to bed- 
rock, reveal a channel region running south and southwest from section 
23, from near where McCormicks Creek leaves the Flatwoods region. <A 
A small tributary in bed-rock flowing its water in the up-stream direction, 
just west of where McCormicks Creek turns west in section 23, also indi- 
eates that a channel once went southwest from this region. There is no 
doubt in the mind of the writer that this region and also the long ex- 
tension north into section 24, was drained to the west and north through 
a well developed underground system. Well No. 14 shows that the 
ancient surface was more than 116 feet below the present surface, and 
more than eighty-five feet below the bed of McCormicks Creek a mile to 
the north. At this place the old stream channel must not have been far 
from the 690 foot contour line. 
The western border of Flatwoods in the region of the headwaters of 
Allistons Branch reveals facts in harmony with those shown by the wells. 
The tributaries of this creek are etching their way slowly into the Flat- 
woods region. The etching is slow because the slope is away from them, 
thereby causing practically all the water, except that which falls immedi- 
ately into them, to flow in the opposite direction. These tributaries are 
deep, V-shaped valleys or ravines in the sandy material at this margin of 
the region. A typical ravine may be found just south of the middle of 
section 27. It begins at an elevation of 760 feet, and descends rapidly to a 
depth of sixty feet or more. The sandy banks on either side are very 
steep. Small erratic boulders may be found in the narrow bottom, amid 
which trickles water seeping from the sandy banks near the bottom. The 
descent continues rapidly until near the 620 foot contour. <A small 
valley flat then begins to appear, and soon the main stream is reached. 
The entire length of this ravine is less than one-fourth mile, and a 
descent of at least 150 feet has been made. The slope away from the 
Flatwoods region towards White River, much cut up by etching ravines, is 
very rapid; this makes the banks or sides of the etching ravines higher 
near their heads than farther down. 
The great amount of sandy material at the head waters of Allistons 
Branch indicates that the old channel found and traced westward by the 
