engine

…in 399 bce directed his engineers to construct military engines in preparation for war with Carthage. Dionysius’s engineers surely drew on existing practice. The earliest of the Greek engines was the gastrophetes, or “belly shooter.” In effect a large crossbow, it received its name because the user braced the stock…

…exception was the trebuchet, an engine worked by counterpoise. Counterpoise engines appeared in the 12th century and largely replaced torsion engines by the middle of the 13th. The trebuchet worked something like a seesaw. Suspended from an elevated wooden frame, the arm of the trebuchet pivoted from a point about…