things like the spheres, baghdad batteries, etc... are called OOPART (Out Of Place Artifacts)
If I remember right Giants came from the word Gigantes (earthborn?)that came from the word Nephilim (those who from heaven came down?).
Again off memory the Nephilim were the Children of earth women and "angels" who "left their first estate" (bodies?).
I've read the Nephilim were the things that came down, but I don't think the old texts read that way, the Nephilim/Gigantes were the hybrid Children of Human/Spirit intercourse/engineering, not the "angels" themselves. The hybrids were gibborim and nephilim.
From what I remember.
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