Great to see Mauro. Forgotten Weapons is an outstanding video channel. They also were good enough to review the Paul Mauser book based on his personal archives:
https://www.youtube.com/watch?v=ZLIpsHe6k3U
They have also collaborated with Mauro on other programs, like this one looking into the Josef Nickle pistols:
https://www.youtube.com/watch?v=X2Gqt28Qqk8
The question of translation was a good one to send to Mauro (and Gerben). Interpreting the archive was a difficult task. It's discussed in the documentary that I produced for the project (currently unreleased). In order to work with original Mauser material you have to overcome challenges including his handwriting (sometimes hastily written notes made during a train trip), interpretation of old German syntax and word usage and context. Formal communications are generally better to deal with than the hand written ones, but the changes in German language usage and wording still present themselves as challenges.
Mauser was an international company, so did business with agents and governments around the world. Language was always an issue to be dealt with, and English was, by no means, considered an "international business language" at that point in the Industrial Revolution.
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.