Canals Law and legislation 101 Navigation 63 Topographical surveying 62 Design and construction 58 Waterways 51 Federal aid to transportation 47 Public lands 46 Inland navigation 43 Rivers 37 Dredging 36 Roads 32 Bridges 31 Expenditures, Public 30 Railroads 30 Securities 28 Ships 28 Budget 25 History 24 Land tenure 24 Harbors 23 Irrigation 23 Public works 22 Appropriations and expenditures 20 International relations 20 Maps 20 Rates and tolls 20 Inland water transportation 19 Government publications 18 Right of way 18