Beheading, if somewhat gruesome, can be one of the quickest and least painful ways to die – so long as the executioner is skilled, his blade sharp, and the condemned sits still.
The height of decapitation technology is, of course, the guillotine. Officially adopted by the French government in 1792, it was seen as more humane than other methods of execution. When the guillotine was first used in public, onlookers were reportedly aghast at the speed of death.
Quick it may be, but consciousness is nevertheless believed to continue after the spinal chord is severed. A study in rats in 1991 found that it takes 2.7 seconds for the brain to consume the oxygen from the blood in the head; the equivalent figure for humans has been calculated at 7 seconds. Some macabre historical reports from post-revolutionary France cited movements of the eyes and mouth for 15 to 30 seconds after the blade struck, although these may have been post-mortem twitches and reflexes.
If you end up losing your head, but aren’t lucky enough to fall under the guillotine, or even a very sharp, well-wielded blade, the time of conscious awareness of pain may be much longer. It took the axeman three attempts to sever the head of Mary Queen of Scots in 1587. He had to finish the job with a knife. [ link ]