Breaking on the wheel

One doesn't hear much about this nowadays, but according to The Companion to British History it was a method of capital punishment popular mainly in continental Europe, though occasionally used in Scotland until the 17th century.
The condemned was tied saltire-wise across a horizontal cartwheel and slowly rotated while the executioner progressively broke his bones with an iron bar. It was sometimes mitigated by an early fatal blow called the coup de grâce.