"wheel, rack"

A Breaking Wheel was an execution device that began to be used in the Middle Ages.  It was especially cruel, and most of Western Europe used it one time or another.  The victim would be tied on a large wagon wheel or cartwheel and then beaten to death with an iron cudgel or wooden club.  In some cases, a merciful coup de grâce would be administered, but sometimes the victim could take several days to die, left tied to the wheel with horrific injuries.  Despite being so utterly and unforgivably barbaric, it was used in Germany as (relatively) recently as 1841.  A popular firework, the Catherine Wheel, is named after this instrument.  The namesake is St. Catherine of Alexandria, a martyred saint from the 3rd Century AD.  Legend states she was sentenced to be executed on the wheel, only for it to break when she touched it; she was beheaded instead.

The Rack is another well known torture device, used to inflict enormous amounts of pain - either as a punishment or interrogation technique.  The victim would be tied to a (usually wooden) frame by the wrists and ankles, and then stretched via a roller and ropes.  Bones would dislocate, and often break, and tissue, muscle, ligament and cartilage would tear.  Like most of these awful pieces of equipment, it began being used in Europe during Medieval times.  Many historical dramas will often have the obligatory 'rack' scene.