^^ The American Geologist. Ansust, i893 
I'ieir 2. About two iiiik's east of Galena, in Jo Daviess 
county, there is a "iiiound" which rises perhaps 200 feet above 
the general upland surface. Looking northwestward from its 
summit we see a sharply dissected plain, broken by no eleva- 
tions within this state. Hut to the south and southwest a 
line of prominent "mounds" rise from 200 to 300 feet above 
the plane which passes along the hilltops of the ordinary u])- 
land surface. Eastward from us a very large portion of the 
country is occupied by long ridges and small plateaus, which 
rise fronj a dissected plain in the same manner and to a simi- 
lar hight as the isolated "mounds." 
Vieir 3. This view is taken five miles northeast of the city 
of Freeport, in Stephenson county. We stand on a broad ridge 
and look across similar ridges to the north and east. But all 
the ridges are of the same hight, and within a few miles they 
merge into a perfectly even sky line. Tracing this line around 
by the west, we find it broken hy a single cone-shaped mound : 
but, turning to the south, we look across a broad basin in 
which the hill tops do not rise to so great altitude as the 
ridge on which we stand. Ten miles distant, howevei-, the 
surface again rises to the level of the hills immediately abtnit 
us, and is apparently a portion of the same dissected plain. 
In the broad shallow basin, which intervenes between the 
higher ridges, we find that, were the valleys filled up to the 
level of the hills, we should have a plain, sloping rapidly from 
the ridges which bound it, but becoming nearlj" level in the 
central portion. While its level is 100 feet lower tluui the 
ordinary upland surface, it is still a very hilly country, for, 
trenched below the bottom of the ancient basin, there are 
comparatively narrow valleys, locally bounded by blurt's. The 
largest af these valleys is occupied by the Pecatonica river. 
^^iew J/.. The divide between the hj^drographic basins of 
Yellow creek and Leaf river is a broad ridge, at some places 
simulating a low, narrow plateau. Taking our position on its 
crest and looking southward, we see a broad valley or basin, 
several miles wide and bounded by a narrow ridge nearly as 
high as the one on which we stand. Trenched into the bottom 
of this basin are narrow valleys of the same system that we 
found in the Pecatonica basin. If we were to go southward 
across this l)asin to the ridga which bounds th e view in that 
