An image of "Study of Two Men in Discussion", created by Raffaello Sanzio from 1509-10 (Silverpoint, 278 x 200 mm).

This site from the Library of Congress links directly to a chronology of events leading to the declaration of independence from Great Britain, the drafting of the document, and Jefferson'vison as stated in the Declaration of...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

A very lengthy page from friesian.com discussing Bohr's theory of electronic energy levels and the explanation of commonly observed atomic emission line spectra. The concept of a photon and Einstein's observation of the photoelectric...

After viewing the PBS documentary, "Lioness", a panel of veterans conduct a discussion about women in combat. The recording of the discussion is available here. March 24, 2009

Discusses the meaning of velocity in terms of a graphical representation. Calculus-based discussion. Good graphics.

A discussion from Georgia State University of different types of mirrors and the images which they create. Discusses different instruments which use mirrors to produce images.

This site from the Colorado State University discusses the tranfer of heat by conduction and convection. Discussion centers around the application of these two heat transfer mechanisms to engines. The variables that effect the resistance...

A commercial site that discusses in detail the grading of diamonds, as well as briefly discussing their structure, physical properties, and historical background.

A commercial site that discusses in detail the grading of diamonds, as well as briefly discussing their structure, physical properties, and historical background.

A commercial site that discusses in detail the grading of diamonds, as well as briefly discussing their structure, physical properties, and historical background.

A commercial site that discusses in detail the grading of diamonds, as well as briefly discussing their structure, physical properties, and historical background.

A commercial site that discusses in detail the grading of diamonds, as well as briefly discussing their structure, physical properties, and historical background.

Very complete set of sites that discuss the trilogy of Aeschylus. Begins with discussion of themes and plot of the "Agamemnon". Explore and find tons of good stuff!

A short essay on Seurat's famous "Sunday Afternoon on the Island of La Grande Jatte." This essay discusses whether this painting is a statement in anti-impressionism or, in fact, a natural progression of the movement's ideas. Interesting...

Georgia State University provides a technical discussion on how voltaic cells produce an external electric current. Equations for the reactions that occur are given and discussed.

Georgia State University provides a technical discussion on how voltaic cells produce an external electric current. Equations for the reactions that occur are given and discussed.

An extensive site that includes an interactive timeline of Greek art. Clicking on hyperlinks take you to a detailed discussion of the individual works of art. Included are photographs of Greek architecture. A great resource for the study...