History 44 Description and travel 13 Indians of South America 11 Politics and government 9 Law and legislation 8 Water 7 Water rights 7 Water utilities 7 Discovery and exploration 6 Travel 6 Civilization 5 Heads of state 5 History and criticism 5 Foreign relations 4 Scientific expeditions 4 Social aspects 4 Economic aspects 3 Emigration and immigration 3 Ethnology 3 Political and social views 3 Political aspects 3 Social conditions 3 Social life and customs 3 Spanish 3 Voyages and travels 3 Agriculture 2 Antiquities 2 Cultural property 2 Democracy 2 Economic conditions 2