This might be Swiss, given that it says "Schweiz" (Switzerland) on it. There's a
Baden in the north there up by Zuerich. I have no idea about the N ("nord?) and
the U ("umgang? unter? ueber?"). The Bruder looks like a proper name, being
without dots over the u.

I can't seem to find anything under searches with Schieblehre or Messschieber
that matching a caliper.

Regarding metric, it took a little while for SI to make its way across the
continent. According to our ever-reliable wikipedia, Switzerland made it
compulsory in 1877.