Image from the Biodiversity Heritage Library.
Contributed by Yale Peabody Museum of Natural History.
| www.biodiversitylibrary.org
Transcription
Ref. 8-93
Section of arch in bluff back
of Prairie du Chien Riv.
Thatu
Limestone
about 20 ft
St Peter sand
50 feet
Devonshire shale
2 mi. 20 feet.
Lower Magnesian
in vertical cliffs near
the top
About 125 feet
Prairie Point