Geology 78
Maine 77
Geomagnetism 42
Acadia National Park (Me.) 25
Stream measurements 22
Streamflow 22
Floods 20
Paleontology 20
Water quality 18
Geology, Stratigraphic 16
Petrology 15
Birds 9
Flood damage prevention 9
Groundwater Pollution 9
Hydroelectric power plants Environmental aspects 9
Maine History 9
Mines and mineral resources 9
Watersheds 9
Environmental monitoring 8
Forests and forestry 8
Hydrogeology 8
New Brunswick 8
Climatic changes 7
Granite 7
Hydrology 7
National parks and reserves Law and legislation 7
Wildlife refuges 7
Geology, Structural 6
Manganese 6
Québec (Province) 6
Rachel Carson National Wildlife Refuge (Me.) 6
Runoff 6
Transportation Environmental aspects 6
United States History 6
Acadia National Park (Me.) Environmental conditions 5
Auditing 5
Groundwater 5
Groundwater flow 5
Land use Law and legislation 5
Manganese ores 5
New Hampshire 5
Peat 5
Vermont 5
Volcanic ash, tuff, etc 5
Water Pollution 5
Wetlands 5
Acadia National Park (Me.) Boundaries 4
Coal 4
Corals, Fossil 4
Evaluation 4
Families 4
Friendship 4
Geochemistry 4
Geophysics 4
Groundwater Quality 4
Historic sites 4
Indians of North America 4
Maine Altitudes 4
National parks and reserves 4
Natural resources 4
Pegmatites 4
Roads Environmental aspects 4
Sea level 4
Seismic prospecting 4
Wild and scenic rivers Law and legislation 4
York River (Me.) 4
Arsenic Environmental aspects 3
City and town life 3
Copper ores 3
Flood damage 3
Forest management 3
Forest surveys 3
Frontier and pioneer life 3
Grants-in-aid Auditing 3
Gravity stations 3
Hazardous waste sites 3
Ice on rivers, lakes, etc 3
Interstate agreements 3
Land titles Registration and transfer 3
Landscape assessment 3
Landscape protection 3
Management 3
Manganese mines and mining 3
Marine sediments 3
Mineralogy 3
Moosehorn National Wildlife Refuge (Me.) 3
Mount Desert Island (Me.) 3
Moving, Household 3
Natural gas pipelines Environmental aspects 3
Natural history 3
New York (N.Y.) 3
Orphans 3
Outdoor recreation 3
Petit Manan National Wildlife Refuge (Me.) 3
Precipitation (Meteorology) 3
Saint Croix Island International Historic Site (Me. and N.B.) 3
Salt marshes Management 3
Sandstone 3
Schools 3
Soldiers 3