History 19,119 Law and legislation 6,273 Geology 5,892 Description and travel 5,831 Politics and government 5,156 Periodicals 4,669 Indians of North America 4,162 Roads 3,303 Finance 3,199 Environmental aspects 3,184 Statistics 3,096 Social life and customs 3,046 Gold discoveries 2,915 Social conditions 2,586 Education 2,542 Gold mines and mining 2,310 Economic conditions 2,237 Water-supply 2,225 Maps 2,113 City planning 2,088 Travel 2,019 Planning 2,010 Women 1,851 Pollution 1,822 Earthquakes 1,783 Housing 1,732 Biography 1,614 Manners and customs 1,528 Mines and mineral resources 1,481 Mexican Americans 1,478 Water resources development 1,456 Public lands 1,441 Land use 1,414 Buildings 1,406 Real property 1,388 Motion picture industry 1,384 Law 1,380 African Americans 1,356 Agriculture 1,312 Economic aspects 1,301 Fiction 1,273 Murder 1,243 Motion pictures 1,240 Railroads 1,229 Management 1,213 Legal status, laws, etc 1,209 Jews 1,203 Antiquities 1,193 Government policy 1,192 Air 1,185 Research 1,181 Groundwater 1,178 Taxation 1,171 Buildings, structures, etc 1,168 Officials and employees 1,164 Exhibitions 1,150 Missions 1,145 Architecture 1,144 Police 1,143 Frontier and pioneer life 1,126 Social aspects 1,098 Transportation 1,080 Art 1,071 Artists' books 1,044 Race relations 1,030 Appropriations and expenditures 1,015 Emigration and immigration 1,015 Services for 1,012 Geology, Stratigraphic 995 Regional planning 980 Study and teaching 970 Employment 947 Water 947 Auditing 945 Budget 928 Gay men 918 Prevention 914 Private investigators 897 Labor supply 891 Harbors 885 Population 880 Histoire 865 Political science 852 Architecture, Domestic 842 Local transit 840 Japanese Americans 839 National parks and reserves 838 Overland journeys to the Pacific 838 Evaluation 837 Chinese Americans 836 PRO Gotham Book Mart (former owner) (Gotham Book Mart Collection copy) 831 Immigrants 830 American poetry 824 Paleontology 800 Outdoor recreation 773 Poetry 773 Investigation 768 Water quality 768 Universities and colleges 767 Labor unions 760