3 1 6 
The American Geologist. 
November, 1893 
<- 
J2 
a 
= 
z 
Situation. 
1 m. N. of Freepori . 
."> m.N.W. of Freeport 
3 m. S. of Freeport . . . 
Cedarville 
Cedarville 
3 m. W. of Freeport.. 
4 m. W. of Freeport.. 
o 
So 
. 
« j. 
.3 3 
43 
M 
s b 
u •- 
O 
fi 
J 
S().m. 
Ft. 
'.. 
950 
1 
850 
10 
2050 
29 
3250 
m 
225 
i 
950 
5 
1100 
"3 
« 
o 
CQ 
Ft. 
140 
240 
235 
160 
175 
100 
165 
- 
Q 
Ft. 
29 
44 
36 
57 
15 
25 
30 
<M *J * 
c a 
o a S 
Cubic 
*3 
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contents. 
~Z z 
$* 
— , a so 
Cubic yds. 
Ft. 
Ft. 
140,000 
50 
.) 
330,000 
175 
25 
640,000 
200 
20 
1,100,000 • 
L33 
25 
21,875 
150 
5 
88,000 
80 
H 
202,000 
145 
10 
.g*2 is a 
OS-- 5 * 
10 : 1 
7 : 1 
10 : 1 
5.8: l 
30 : 1 
10 : 1 
14 5: 1 
No. 1 is at the present time occupied by running water only 
in spring and during periods of excessive rainfall. Several of 
the others represent a portion only of the real gorge. Only 
those parts were measured that are entirely of glacial and 
postglacial age, as in other portions it is difficult to eliminate 
preglacial erosion. In valleys of this class, extending over 
only a portion of the stream's course, the cubic contents are 
to he considered in relation to the length of the measured 
portion. More importance is attached to the width of the 
trough than to the amount of material removed. 
The Cedarville gorge (No. 4 of the table) may he taken as 
the type, and a description of it will apply, with some modi- 
fications, to all the others. Cedar creek, situated in the cen- 
tral part of Stephenson county, flows in a general southwest 
direction into Richland creek. After traversing a broad val- 
ley with gently sloping sides covered with drift and loess, it 
suddenly enters a deep, narrow gorge with steep, rock-hound 
walls. The contraction of the valley from 3,000 to 160 feet is 
conspicuous and readily attracts attention. The old valley 
can be traced around by the south, hut is partially filled with 
sand ridges. The sides of the gorge are at some places per- 
pendicular, but generally slope at an angle of about 30°. The 
bottom is flat, and consists of a lied of dark brown alluvium, 
through which the stream meanders, sometimes touching one 
side and sometimes the other, undermining the walls and 
widening the valley. After about three-fifths of a mile the 
stream enters a small preglacial valley and the gorge widens, 
hut the same canon-like character prevails to its end. A small 
tributary occupies a portion of the old valley, and when Ce- 
dar creek again enters this valley the significant fact isleamed 
