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"The romans had no knowledge of gunpowder, siege cannon, or field guns; but the place of modern artillery was supplied by what in general were called tormenta. These were powerful engines for hurling missiles, the propelling force being furnished by the twisting of rope, sinews, or hair. They were used in siege operations rather than in ordinary battle."

Tormenta Within a Fortified Camp

"The romans had no knowledge of gunpowder, siege cannon, or field guns; but the place of modern artillery…