"I would have sworn my life on your interpretation:" James Hall, Sir William Logan and the "Quebec Group"

The establishment of a stratigraphic succession for the Paleozoic rocks south of Quebec City created a bitter international confrontation in the 1860's. Establishing the geological framework for Canada after 1842, Sir William Logan relied on the system of nomenclature established by the New York Geological Survey and James Hall. Moreover, in elaborating a stratigraphic succession for the Quebec rocks, Logan drew directly on Hall's paleontological expertise. Their combined skills contributed to a coherent column for the "Quebec Group." Yet in 1861 new trilobite evidence proved the column wrong, created a strident conflict between Logan and Hall, dragged them into the "Taconic" controversy and seriously damaged their close working relationship.