Canals 193 Railroads 50 Navigation 13 Law and legislation 12 Canals--Pennsylvania 11 History 11 Early works to 1850 7 more ... Canaux 6 Public works 6 Rates and tolls 6 Coal trade 5 Finance 4 Inland navigation 4 Lotteries 4 Water-supply 4 Banking law 3 Canal construction--19th century 3 Costs 3 Governmental investigations 3 Internal improvements 3 Locks (Hydraulic engineering) 3 Railroad law 3 Surveying 3 Taxation 3 Telegraph 3 Transportation 3 Appropriations and expenditures 2 Bridges 2 Coal 2 Coal mines and mining 2 Commerce 2 Design and construction 2 Pennsylvania imprints 2 Power utilization 2 Rates 2 Rules and regulations 2 Tolls 2 Water-power 2 Women in the book trades 2 Aeronautics 1 less ...