A petrographical study of the rocks of Mount Royal.

Mount Royal, situated as it is on the south-east border of the Island of Montreal, is surrounded for many miles by an almost flat plain; this plain is bounded on the north by the foothills of the Laurentian plateau and extends southward to the Appalachian Mountains; this almost flat plain was once the bottom of an early Palaeozoic sea, and now constitutes the broad valley of the River St. Lawrence. [.