Railroads Commerce 19 Rates 5 Freight 4 Early works to 1850 3 History 3 Coal trade 2 more ... Appropriations and expenditures 1 Baltimore and Susquehanna railroad 1 Canals 1 Confiscations and contributions 1 Congresses 1 Finance 1 History, Local 1 Inland water transportation 1 Interstate commerce 1 Location 1 Maritime History--Commerce 1 Philadelphia (Pa.)--Hog Island 1 Philadelphia and Erie railroad 1 Politics and government 1 Port of Philadelphia 1 Railroad Jubilee, 1851 1 Railroads and state 1 Transportation 1 Transportation, Automotive 1 less ...