I just heard the standard history channel narrator and almost stopped watching. Then I saw that it was one of the old series that were pretty good.
I didn't see it in the part I watched but I'm assuming you're talking about the Belly Bow - Greek Crossbow? I think only Syracuse used it en'masse though there are a few samples of those and Roman torsion crossbows. However, I don't think it was ever widely adopted.
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