[The following article was accompanied by a series of diagrams representing the size, location, and relative position of the various out-crops.] Middle River rises on the eastern slopes of the divide in Adair and Guthrie Counties. It flows just south of Winterset, in Madison County, then northeasterly to the northeast corner of Warren County, where it takes an easterly direction for four miles and flows into the Des Moines River, about eight miles below the city of Des Moines. Consequently, a line drawn along Middle River from its mouth to Winterset, a distance of about fifty miles, passes from close to the lower strata of what White calls the "Middle Coal Measures," across the entire series of both the "Middle" and "Upper Coal Measures." In the sections found along this line we may ascertain the local thickness of the different strata, some facts in regard to the continuity of the different strata and of the different seams of coal, also the position of the border between the "Middle" and" Upper Coal Measures;" or between the "Lower" and " Upper Coal Measures," following the classification that will probably be accepted.
Proceedings of the Iowa Academy of Sciences
©1892 Iowa Academy of Science, Inc.
Tilton, J. L.
"Strata between Ford and Winterset,"
Proceedings of the Iowa Academy of Science, 1(Pt. 3), 26-27.
Available at: https://scholarworks.uni.edu/pias/vol1/iss3/10