On the top floor of the library, the books are arranged according the Dewey Decimal Classification system. Once you know the general area where books on your topic are kept, it can be very effective to browse the shelves.
900 – History, geography, and biography
- 900 Geography & history
- 901 Philosophy & theory
- 902 Miscellany
- 903 Dictionaries & encyclopedias
- 904 Collected accounts of events
- 905 Serial publications
- 906 Organizations & management
- 907 Education, research, related topics
- 908 With respect to kinds of persons
- 909 World history
- 910 Geography & travel
- 911 Historical geography
- 912 Graphic representations of earth
- 913 Ancient world
- 914 Europe
- 915 Asia
- 916 Africa
- 917 North America
- 918 South America
- 919 Other areas
- 920 Biography, genealogy, insignia
- 921-928 This range is reserved as an optional location for biographies, which are shelved alphabetically by subject's last name.
- 929 Genealogy, names, insignia
- 930 History of ancient world
- 931 History of ancient world; China
- 932 History of ancient world; Egypt
- 933 History of ancient world; Palestine
- 934 History of ancient world; India
- 935 History of ancient world; Mesopotamia & Iranian Plateau
- 936 History of ancient world; Europe north & west of Italy
- 937 History of ancient world; Italy & adjacent territories
- 938 History of ancient world; Greece
- 939 History of ancient world; Other parts of ancient world
- 940 General history of Europe
- 941 General history of Europe; British Isles
- 942 General history of Europe; England & Wales
- 943 General history of Europe; Central Europe; Germany
- 944 General history of Europe; France & Monaco
- 945 General history of Europe; Italian Peninsula & adjacent islands
- 946 General history of Europe; Iberian Peninsula & adjacent islands
- 947 General history of Europe; Eastern Europe; Soviet Union
- 948 General history of Europe; Northern Europe; Scandinavia
- 949 General history of Europe; Other parts of Europe
- 950 General history of Asia; Far East
- 951 General history of Asia; China & adjacent areas
- 952 General history of Asia; Japan
- 953 General history of Asia; Arabian Peninsula & adjacent areas
- 954 General history of Asia; South Asia; India
- 955 General history of Asia; Iran
- 956 General history of Asia; Middle East (Near East)
- 957 General history of Asia; Siberia (Asiatic Russia)
- 958 General history of Asia; Central Asia
- 959 General history of Asia; Southeast Asia
- 960 General history of Africa
- 961 General history of Africa; Tunisia & Libya
- 962 General history of Africa; Egypt & Sudan
- 963 General history of Africa; Ethiopia
- 964 General history of Africa; Morocco & Canary Islands
- 965 General history of Africa; Algeria
- 966 General history of Africa; West Africa & offshore islands
- 967 General history of Africa; Central Africa & offshore islands
- 968 General history of Africa; Southern Africa
- 969 General history of Africa; South Indian Ocean islands
- 970 General history of North America
- 971 General history of North America; Canada
- 972 General history of North America; Middle America; Mexico
- 973 General history of North America; United States
- 974 General history of North America; Northeastern United States
- 975 General history of North America; Southeastern United States
- 976 General history of North America; South central United States
- 977 General history of North America; North central United States
- 978 General history of North America; Western United States
- 979 General history of North America; Great Basin & Pacific Slope
- 980 General history of South America
- 981 General history of South America; Brazil
- 982 General history of South America; Argentina
- 983 General history of South America; Chile
- 984 General history of South America; Bolivia
- 985 General history of South America; Peru
- 986 General history of South America; Colombia & Ecuador
- 987 General history of South America; Venezuela
- 988 General history of South America; Guiana
- 989 General history of South America; Paraguay & Uruguay
- 990 General history of other areas
- 991 Not assigned or no longer used
- 992 Not assigned or no longer used
- 993 General history of other areas; New Zealand
- 994 General history of other areas; Australia
- 995 General history of other areas; Melanesia; New Guinea
- 996 General history of other areas; Other parts of Pacific Polynesia
- 997 General history of other areas; Atlantic Ocean islands
- 998 General history of other areas; Arctic islands & Antarctica
- 999 Extraterrestrial worlds