air circulation in a mining situation?

Nope. This situation or action has nothing to do with mining.

Though a lot of mining has to be done before this special process can begin :03:

I wrote that the sketch was presumably done in the 16th century, so too late to be medieval – the middle ages/medieval officially ends with the discovery of the New World (read America) in 1492.

But the process itself being shown can have been done also earlier, just making this known by writing it down was done later.
As it happened the whole process (of which the depiction is only a part) was kept secret, and only a handful of people knew how to do it.


Hint, but maybe misleading (hello Aktungbby :O:): some certain advances in perfecting the procedure was the one of two major reasons some duke of Medina-Sidonia was beaten.

Making gunpowder?

Not gunpowder but you are getting warm in every sense of the word...

Fiery cannonade?

making saltpeter?

Does that look like a "fiery cannonade"? :hmmm:
Or I somehow have difficulties translating this :oops:
One might say it has something to do with what you create a fiery cannonade..

No.
Saltpeter mixed with something else (together known as gunpowder) will be used with the end product.
Nothing to do with what is being done on the sketch.

https://i.imgur.com/UUbKEHV.jpg Making early grenades?

Hehe no
not a grenade

Hint, maybe misleading

As said before this is a process, on this picture the *'Bodenstueck'* is missing yet

Rocket launching device?

I think this may have something to do with the weather - perhaps attempting to control it?