Who is the other one you have in mind? I thought both Isidore and
Tacitus described a flat earth.
The other one I was thinking of was Lactantius.
Isidore in fact stated the roundness of the earth, in Etymologies, in the
chapter on Africa. As for Tacitus, I can't comment for lack of knowledge.
What I had meant to say, however, was CHRISTIAN authors, so Tacitus doesn't
count for my intended point. Sorry for the confusion.
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by Jeff Russell that it refers to will answer questions far better than I