The ballista is an ancient missile launcher designed to hurl long arrows or heavy balls. The largest could accurately hurl 60-pound (27-kg) weights up to about 500 yards (450 m). The Greek version was basically a huge crossbow, while the Roman ballista was powered by torsion and used two separate arms joined at their ends by the cord that propelled the missile. Once the Roman Empire declined, so too did the ballista—it was too challenging and expensive to build. Which weapons took its place?
Back in the day
Also known as the Five-Power Treaty, the Washington Naval Treaty was an agreement signed in the wake of World War I in an effort to prevent an arms race by limiting naval construction. Signed by five of the major Allied Powers—Great Britain, the US, Japan, France, and Italy—the treaty limited the tonnage of aircraft carriers and capital ships and imposed proportional limits on the number of warships each signatory nation could maintain. For how long did signatories adhere to these terms?
Born on a day like today
Beatrice was a young Roman noblewoman whose execution for patricide aroused public sympathy and inspired various poems, novels, and dramas. Her father, Francesco, was a notoriously vicious and cruel man. After years of brutal treatment, Beatrice, her stepmother, brother, and stepbrother could take no more and had Francesco killed. Despite efforts by the people of Rome to obtain mercy for the conspirators, Pope Clement VIII was unyielding. What might have motivated him to uphold their sentences?