I've read many of your posts Koen, and I like your method of analyzing things!
The wood of the plant being used for arrow shafts, or fibers of the plant being used to fasten feathers, are both practical uses of the plant. I see nothing wrong with that, and it could well be (if this line of thinking is even correct) that one of those two possibilities, or something similar, is the intended meaning of this hypothetical mnemonic device.
But I always feel a bit of a let-down when I remember that we just don't know whether that's the intended interpretation of a specific such device. It might as well be that the author modeled the leaf as an arrow because the initial letter, or first few letters, or entire word for "arrow" in his language would help to remember... the name of the plant? some cultural connotation with the plant? some religious ceremony where the plant is used? a disease that the plant helps against? and so the list goes on and on, as I see it
We probably need to establish a "beyond doubt" certain link between two interpretations of such mnemonic devices before it's worth spending much time researching a possible lead.
I like the effort by Don to create .PDF files listing mnemonic devices, though I disagree with almost all of his identifications. Or rather, I can "sorta kinda almost" see it, but remain unconvinced.
But of course, this is the devil of it all, eh? We just can't *nail anything down* and reach a consensus. Everything is in question about the VMS..! Up until maybe a week ago, before I read through past posts on this message board, I thought that the Emp. Rudolph connection was well-established and accepted. But now I see that some (and a significant number) of people even voice their doubt over that provenance! (Of course I'd seen crackpot theories, but no serious people suggesting it...)
I think we all hate and love the original scribe(s) of this ol' manuscript. Such a source of frustration, but at the same time, I can't even list all the things I've learned doing research trying to "figure it out".
Hah, I'd love to think that's the true purpose! Make something mysterious but with drawings that clearly pertain to different sciences, and everyone trying to figure it out will learn tons about herbalism, astronomy, balneology, pharmacology, heraldry, cartography... etc. etc...
I'm just joking, but then again! I've probably learned more in my research than the plaintext could ever teach me
