Highly detailed map of Pennsylavnia, hand colored by counties, and showing towns, railroads, railroad stations, rivers, lakes, etc. One of the most detailed commercial atlas maps of the region.
O. W. Gray was a publishing firm based in Philadelphia. Later, they published as O. W. Gray & Son. They published atlases in the late nineteenth century. Gray's National Atlas was one of the most successful commercial ventures of the 1870s and one of the last to employ hand coloring on maps.