Section 9.5 History

This is one of the best all around sites that I have found. It is titled "The MacTutor History of Mathematics Archive."
http://www-history.mcs.st-and.ac.uk/~history/

This is an award-winning site that links to all sorts of mathematics information.
http://archives.math.utk.edu/

These sites are dictionaries of units of measurement.
This site has many nice links to other sites.
http://www.unc.edu/~rowlett/units/index.html

This site is very complete.
http://www.ex.ac.uk/cimt/dictunit/dictunit.htm

Links