http://micro.magnet.fsu.edu/optics/timeline/people/foucault.html
http://en.wikipedia.org/wiki/Leon_Foucault
http://www.1911encyclopedia.org/Jean_Bernard_Leon_Foucault
http://www.infoplease.com/ce6/people/A0819331.html
http://www.britannica.com/ebi/article-9323731
_ Foucault's pendulum.
http://jp.youtube.com/watch?v=wlhHWYKswik
_ Foucault's Pendulum, Paris
http://jp.youtube.com/watch?v=K9OS5qY0x2I
_ Perpetual Motion
http://jp.youtube.com/watch?v=us7YB7eiOeQ