French mystery revealed...

[major_clanger]

...not much of a mystery actually, as many of you correctly identified this object as a lavender still. It was at Le Musée de la Lavande in Provence, which turned out to our surprise to be really more of a Museum of Steampunk Lavender-Processing Technology. More pictures to follow, with more brass and pressure gauges than you can shake a sprig of lavender at.