Ballista

Ancient ranged weapon

The ballista (Latin, from Greek βαλλίστρα ballistra and that from βάλλω ballō, "throw"), plural ballistae or ballistas, sometimes called a bolt thrower, was an ancient projectile weapon that launched either bolts or stones at a distant target. Developed from earlier Greek weapons, it relied on different mechanics, using two levers with torsion springs instead of a tension prod (the bow part of a modern crossbow). The springs consisted of several loops of twisted skeins.

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