Fig. 7
From: The Glarus Double Fold: a serious scientific advance in mid nineteenth century Alpine Geology
Stratigraphic column of the rocks exposed in the Glarus Alps (copied from Escher 1846b). Items 12–13 are unconsolidated Quaternary deposits; items 9–11 are Tertiary formations; items 4–8 are Mesozoic formations (with fossil content indicated in bold script), and item 3 is Carboniferous black shale with coal intercalations. Note that Escher obviously hesitated to integrate the Verrucano (“Sernfschiefer und Sernfconglomerat” named after the river Sernf, items 1 and 2) into the normal stratigraphic column. Instead, he put them into the column of the crystalline rocks (column to the right)