There are two versions of the Gravity Flux spell depending on which class researches it, but it seems it was scribable by either class despite what the scroll said.
Thread (with bonus Gordon getting schooled) from 2000:
https://groups.google.com/g/alt.game...m/tiGbNcn9ojsJ
Another thread from 2001:
https://groups.google.com/g/alt.game...m/58MGXEXG6jYJ