The international system of weights and measures (by Russ Rowlett) can be found here:
http://www.unc.edu/~rowlett/units/sipm.html
The book Flatland (suggested as a book report at the end of the chapter) can be found online at:
http://www.alcyone.com/max/lit/flatland/
A very useful dictionary of units of measurement is found at this site:
http://www.unc.edu/~rowlett/units/index.html