Most stuff gnomes invent fit into the technology level of the FR. D&D in general is early renaissance and there specialists had a basic understanding of chemistry although often coupled with alchemy and there was also construction of clockwork, mainly in the Islamic part of the (real) world that had its golden era during that time.
Yeah but couldn't like humans do that? I just really hate gnomes and want them gone.
Humans certainly also know that. After all there are several highly advanced, for D&D, human nations. But gnomes are simply a bit better.
