E-Source Home  >  Databases by category  >  Science E-Source Targets National Geographic Virtual Library (Login required - click here)     National Geographic Magazine Archive from 1888 to 1994 Science Online (Login required - click here)     Presents a broad range of scientific disciplines through extensive definitions, essays, diagrams, biographies, and experiments. Science Reference Center (Login required - click here)     Science Reference Center is a comprehensive research database that provides easy access to a multitude of full text science-oriented content. This database contains full text for nearly 640 science encyclopedias, reference books, periodicals, etc. Topics covered include: biology, chemistry, earth & space science, environmental