The Perry County Divide extends in an irregular line from the northwest to the southeast. It begins in Thorn township separating the streams that flow into Buckeye Lake and Jonathan's Creek from Rush- creek and Big Walnut. Somerset is situated on it. Passing through Clayton township it sweeps to the east toward McLuney. The C. & M. V. Tunnel cuts it east of New Lexington. Then turning toward the west again it completes a horse-shoe by circling south of New Lexington. The T. & O. C. railroad tunnels it about a mile south of the county seat. It continues westward as far as Bristol. This place occupies the summit of a ridge from which five streams have their sources.---Turkey Run of Rushcreek, South Fork of Jonathan, Little Mondaycreek, Big Mondaycreek and a branch of Sundaycreek. The water-shed south of Bristol turns toward the northeast, forming the ridge between the South Fork of Jonathan and Sun- daycreek. Passing south of Moxahala the T & O. C. R. R. has made through it the longest tunnel in Perry county. The dividing ridge leaves the county at Porterville. It is 114 miles long and passes through nine townships: Thorn, Hopewell, Reading, Clayton, Harrison, Pike, Saltlick, Pleasant and Bearfield. Its average elevation is about 450 feet above Lake Erie and about 1,000 feet above sea level.