The Franklin Institute
Franklin Institute: The Case Files: History of Energy
An early history and biographies of the most prominent scientists involved in developing the main sources of energy used in the twentieth century.
Massachusetts Institute of Technology
Mit: Invention of the Week: William D. Coolidge: The X Ray Tube
Read about William D. Coolidge, his education, work, and his invention--the X-Ray Tube--as well as other medical innovations he is credited with. Learn how x-rays work and how they have contributed to the medical world.
National Inventors Hall of Fame
National Inventors Hall of Fame: William D. Coolidge: Vacuum Tube (X Ray)
This site provides a brief biography on William D. Coolidge, inventor of the X-ray tube, also known as the "Coolidge tube."