The crossbow traded speed for patience, and changed who could shoot
A longbow demands years of practice and serious muscle, because the archer must draw and loose almost in one movement. The crossbow sidestepped both problems. A trigger holds the string back, so a soldier can cock it early and aim at leisure, letting relatively untrained troops shoot with real precision.
The weapon is essentially a bow, called the prod or lath, mounted crosswise on a frame known as the tiller or stock, with a lock holding the drawn string until a trigger releases it. It fires bolts or quarrels, though arrow works too, and the old word vire was once used. Even the term prod has a quirky history: one scholar traced it to a nineteenth-century mistranslation of rodd in a sixteenth-century inventory of crossbow gear.
China built the first known crossbows in the first millennium BCE, and they transformed the role of missile weapons, particularly in the Qin wars of unification and later Han campaigns against northern nomads and western states. The Chinese trigger was an elegant piece of casting: three bronze parts inside a hollow bronze housing, dropped into a slot carved in the tiller and pinned with two bronze rods. Greece probably developed its own crossbow independently, and most medieval European names for the weapon come from ballista, a Greek torsion siege engine that looked similar but worked on a different principle.
Because a cocked crossbow stays ready, teams could work in relays, with one person shooting while others reloaded. Heavy war crossbows needed levers, belt hooks, pulleys, windlasses or a geared crank called a cranequin to span them. That was the catch: reloading was slow and fiddly on a battlefield. Medieval versions were also inefficient, since the string travelled only a short distance before releasing the bolt and their steel prods and heavy strings moved sluggishly despite enormous draw weights. Modern designs have fixed those weaknesses.
Firearms long ago displaced bows and crossbows in war, but crossbows remain popular for hunting, target competition and shooting quietly. A person who uses one may be called a crossbowman, arbalist or arbalister, after the arbalest, a twelfth-century European type, though dictionaries have disagreed over whether arbalist means the shooter, the weapon or its maker.
Source: Crossbow
