Art. VIII.] Davis, Drainage Modification. 171 
A view to the east from such an elevation shows the nar- 
row valley of the Muskingum. To the west Jonathan creek 
valley winds its way among the carboniferous capped hills. 
Across the Muskingum numerous smaller valleys open toward 
the river with northward direction ot discharge . To the north- 
west the valley of the Licking is outlined. 
As indicated on the map, Plate XXV, broken crossed lines 
trace the divides through a portion of the country represented. 
In the western part of Perry county a divide separates the 
Jonathan creek drainage in Hopewell and Thorn townships from 
the Rush creek drainage. Almost at right angles to this, an- 
other divide running through Reading and Clayton townships 
of Perry county, and continuing down into Morgan county, 
separates^ the drainage of Jonathan creek from that of the east 
branch of Rush creek. The C. and M. railroad tunnels 
through this divide near New Lexington, as does the B. and O. 
near Somerset. 
Beginning in Hopewell township of Licking county a di- 
vide runs southeast through Hopewell township of Muskingum 
county. Following the county line between Muskingum and 
Perry counties it continues south into Clayton and Harrison 
townships of Perry county, intersecting the Rush creek divide 
near New Lexington. It is in this divide that the Jonathan 
creek col is located. 
Let us now look for some explanation of the topography 
of Jonathan creek valley. The whole succession of events ac- 
companying the first advance and final recession of the great 
ice sheet is considered and an explanation attempted on such a 
basis. Before the advance of the ice sheet, whose front ex- 
tended to the north and south line through Licking and Perry 
counties, represented on the map, Plate XXV, with a lobe 
of ice running up the Jonathan creek valley as far as Glenford, 
Jonathan creek comprised two small streams heading on the 
opposite side of a north and south divide. The stream flowing 
to the west rising in Clayton township of Perry county, cours- 
