If they think that they will maintain to the end the equanimity of their prayer-lives, they are wrong, because the law demands the full traitor's penalty, the short spin in the wind and the conscious public disembowelling, a brazier alight for human entrails. It is the most horrible of all deaths, pain and rage and humiliation swallowed to the dregs, the fear so great that the strongest rebel is unmanned before the executioner with his knife can do the job; before each one dies he watches his fellows and, cut down from the rope, he crawls like an animal round and round on the bloody boards.
— Wolf Hall by Hilary Mantel
Is it a part of the punishment? With a hint from the last sentence ("cut down from the rope"), I am guessing it is to do with some kind of hanging.