The New Encyclopaedia Britannica: Macropaedia: knowledge in depth. 19 v

19th century abrasive accelerator acid actinide actor Adams adhesives administrative adult advertising Aegean aerospace Aeschylus aesthetic Afghanistan agriculture aircraft airplane animals artist atomic Bantu Bantu languages basic behaviour Bronze Age Cameroon carved Central centre changes Chari-Nile languages coast Congo contains countries Cretan Crete crops cultural Cyclades dance Djibouti early East Egypt electrons engineering Ethiopia example farm feet figures flight Ghana important increase industry Kabul Kenya Khoisan Knossos known Lake land languages mainland major masks ment metal modern mountains Mycenae Niger Nigeria Nilotic northern organization oxidation particles patterns percent period plants political population production proton region River Sahara savanna sculpture soil solvent South Africa southern species style Sudan Tanzania temperature theory tion tons traditional tropical United usually West Africa western Yoruba Zaire