The book pdf pg 34 has a reference to a Hermann Bruder, looks like he is in
many businesses, but this one looks like an Iron works If I;m reading
abbreviations correctly.  Also, the tool has the look of many German Silver
drafting tools, so maybe determining the German word for drafting, and
googling like below.

https://www.google.com/books/edition/Adressbuch_aller_L%C3%A4nder_der_Erde_der_K
a/XRx9sYiVUvkC?hl=en&gbpv=1&dq=%22bruder%22+werkzeug+%22baden%22+%22schweiz%22&p
g=RA1-PA34&printsec=frontcover


Image of vintage drafting stuff front and center here

https://kirkhmb.smugmug.com/Woodworking/Woodworking-Tools/i-DBPgTLj

Kirk in HMB, where the chainsaws and tree chippers are revving up for
another day of meeting interrupting.

On Tue, Sep 7, 2021 at 9:29 AM sushimonster via groups.io  wrote:

> Galoots!
>
> I've found this small brass calliper, which looks finely made. It seems to
> date from when units of measurement varied across Europe, before widespread
> adoption of the metric system - as it records measurement for Baden (German
> province which used the Zoll, Fuss or Elle unit), Switzerland (Similar to
> Baden, depending on region) and Paris ( the Elle), from the little I can
> find on this.
>
> As far as I know, Paris was one of the first areas of France to go metric
> in 1795 - which hints that this piece could be quite early? I'm assuming
> that "BRUDER" stamped on the end might be the maker's mark, but I've never
> heard of the name Bruder as a tool or instrument maker?
>
> Has anyone come across other tools baring the name Bruder at all? It's a
> nice little find, so I'd really like to fill in some knowledge gaps about
> it if I can, before I store it away in the very crowded "Mysteries I
> haven't solved yet" draw :)
>
> ...but then there's that strange dot under the D. Does that mean an
> abbreviation of the name, or is it just a random mark in the brass?
> Apologies about my rusty German knowledge - it's been a while since I took
> it at school.
>
> https://groups.io/g/oldtools/album?id=267887
>
>

-- 
Kirk Eppler