A series of columnar sections constructed from surface observations and the records of eleven oil wells situated between Bradford in McKean County and Ridgway in Elk County showing the relation of the lower caboniferous coal beds to the Bradford oil producing sand and the thickening of the sub conglomerate rocks

Public domain image of the vintage map from NYPL Lionel Pincus and Princess Firyal Map Division, free to use, no copyright restrictions image. The Lionel Pincus and Princess Firyal Map Division is one of the world’s premier map collections in terms of size, scope, unique holdings, diversity, and intensity of use. Established in 1898, our holdings include more than 433,000 sheet maps and 20,000 books and atlases - Picryl description