Plate XLI from The Origin and Relations of Central Maryland Granites (Extract from the 15th Annual Report of the U. S. Geologic Survey, 1893-94) by Charles Rollin Keyes, 1895. Caption is "Gneiss Inclusion in Granite; Waltersville Granite Quarry, near Woodstock, Maryland." Today the gneiss is mapped as the Baltimore Gneiss and the granite is the Woodstock Quartz Monzonite.