I saw a Vuillaume labelled bass (I think the year was 1850) at the university in Stockholm some months ago. Smallish. Distinctly slender shoulders, looked a lot like this Mirecourt bass:
The wood on the V was much more exquisite, though; tightly flamed maple in the back. I seem to remember that this was actually a thin veneer over some supposedly less extravagant wood, but don't call me on this one; I easily imagine things.
I don't remember the exact colours of the varnish nor do I know how to describe them correctly, but it was darker than this Mirecourt bass, maybe - maybe! - with a slight hint of dark red or burgundy.
Sound was sweet on the top string, but it didn't carry a lot of power. Then again, size wasn't on its side, and neither are the facts that it is a rarely used institutional instrument that also wasn't exactly in top condition. I don't think it was an exceptional instrument to begin with, but a lesser restoration and fine tuning and it would become a good bass for its size.