The Springal or Espringal was a mechanical artillery device used for throwing large bolts.
There is a diagram of a springal in an 11th-century Byzantine manuscript. In Western Europe, springals became popular during the 12th and early 13th centuries.
Because springals used a torsion device with twisted skeins of silk or sinew to power two bow-arms, springals were also known as “skein-bows”. Rectangular springals on wheels were better for besieging fortifications, while moujnted ones were used for defending castles as they could aim down from turrets and bastions.
![Medieval Weapons: Springald.](https://medievalbritain.com/wp-content/uploads/elementor/thumbs/medieval-weapons_springald-p425dott7cspsfjg53k70rvc8pyfyiumf3iufk5nrc.jpg)
Medieval Springals
The medieval springal was constructed similarly to the Greek or Roman ballista, with the difference springals had inward swinging arms (and ballistae have outward-facing bow arms). These smaller arms faced forward when not bearing tension. When tension accumulates, they bend towards the operator using the windlass.
There is a large model of a springal at the Tower of London. The only full-size reproduction (8 feet long and capable of hurling a 2.4 kg bolt over 55 meters) can be found in the Royal Armouries Museum at Fort Nelson, Portsmouth.
Depictions of Springals
![A decoration from the foot of a page of The Romance of Alexander, MS Bodlein 264 (circa 1338-44)](https://medievalbritain.com/wp-content/uploads/2021/03/springald-manuscript-depiction.jpg)
![Torsion springald in Roberto Valturio's De Re Militari (1472)](https://medievalbritain.com/wp-content/uploads/2021/03/Valturio_Springald-768x1059.png)