JAMES STEVENSON is the author of House-planning, Surface Geology of South-west Pennsylvania and Adjacent Portions of West Virginia and Maryland, Report of Progress in the Fayette & Westmoreland District of the Bituminous Coal-fields of Western Pennsylvania: The Ligonier Valley, Report of Progress in the Fayette & Westmoreland District of the Bituminous Coal-fields of Western Pennsylvania, The Civilization of South Eastern Africa.