Answer:
Yes a document by a British soldier is trustworthy. This is a firsthand account, meaning that it was written by a person who actually experienced the event which they are writing/talking about.
The most important translator of this group was the Syriac-speaking Christian Hunayn Ibn Ishaq (809-873), known to the Latins as Joannitius.
I believe it was Germany, hope this helps.
They invented things like the pulley, paper made from papyrus.
