They have so many incredible artifacts (for weights and measures but also so much more: engineering, physics, civil engineering, machining,...)
I spent 4 hours to there and was surprised to see so many tourists, this is not a place I expected people visiting Paris to go to. There were no crowds though.
The top part is really great, you get to see how much people did with so little. So is the chemistry part.
I found the steel replica of the kilogramme and the meter, and of course the Foucault pendulum (in the neighboring refurbished church).
This is truly an interesting museum, on part with the museum of discoveries (musée de la découverte) which is unfortunately close now for a few years for renovations (or at lest was recently planned to be closed). Much better than La Vilette.
So thank you again!
The Musée de Sèvres (or Bureau des Mesures as it is called now) has the original kilogramme and meter iridium reference, hidden in the basement ;( So if the director has a change of heart, I am all in!