In June and July of 1191, Richard the Lionheart (the Duke of Normandy) laid siege to the city of Acre as part of the medieval Crusades.
The Duke concentrated on constructing siege machines and placing trebuchets [petrariae - literally, stone hurler] in suitable places. He arranged for these to shoot continually day and night. He had one excellent one which he called "Bad Neighbor" [Malvoisine]. Its continual bombardment partly destroyed the main city wall and shattered the Cursed Tower. On one side the Templars' trebuchet wreaked impressive devastation, while the Hospitallers trebuchet also never ceased hurling, to the terror of the Turks.
Besides these, there was a trebuchet that had been constructed at general expense, which they called "God's Stone-Thrower". A priest, a man of great probity, always stood next to it preaching and collecting money for its continual repair and for hiring people to gather the stones for its ammunition. This machine at last demolished the wall next to the Cursed Tower for around two perches' Length [11 yards or 10 meters].
The count of Flanders had had a choice trebuchet, which King Richard had after his death, as well as another trebuchet which was not so good. These two constantly bombarded the tower next to a gate which the Turks frequently used, until the tower was half-demolished. Besides these, King Richard had two new ones made with remarkable workmanship and material which would hit the intended target no matter how far off it was. . . . He also had two mangonels [traction trebuchets] prepared. One of these was so swift and violent that its shots reached the inner streets of the city meat market.
King Richard's trebuchets hurled constantly by day and night. It can be firmly stated that one of them killed twelve men with a single stone. That stone was sent for Saladin to see, with messengers who said that the diabolical king of England had brought from Messina, a city he had captured, sea flint and the smoothest stones to punish the Saracens. Nothing could withstand their blows; everything was crushed or reduced to dust.