The physical principles behind daredevil rides such as the roller coaster and the free-fall. This site combines an introduction to the basic physics of the rides with some historical notes on the rides themselves.
Information from the CVO, an organization that provides information on volcanoes and other natural hazards including earthquakes, landslides, and debris flows, in the western United States and elsewhere in the world.
From the Le Moyne College Department of Chemistry, this site offers classic papers on a wide range of chemistry topics, historical information in the form of a chemistry calendar, a glossary of terms and Internet resources.
These maps present an accurate, objective, and realistic graphical compilation of contemporary global tectonic and volcanic activity, which can serve as a scientific, educational, and research planning tool.