From Folklore of the Isle of Man, A.W.Moore, 1891

"It is supposed that in old times the usual result of the legal procedure against Witches was that they were subjected to two so-called forms of ordeal, but which were really means of putting them to death, as, if they survived the first, the second would almost certainly prove fatal, for they were said to have been thrown into the middle of the Curragh Glass, or "green bog" pool, in the valley below Greeba mountain. If they sank, their bodies were taken out of the water, carried home, waked, and received a Christian burial ; but if; to save themselves from drowning, they managed to paddle to either side, they were instantly declared guilty of the crime of which they were charged, and were consequently either burned alive as unconvicted witches. or rolled from the top of Slieau Whallian in spiked barrels"

You should be safe Helen as you can't buy reliable spiked barrels nowadays.