Summary

1911 Encyclopædia Britannica, Volume 8… (1911)

Sometimes, however, the Ducking-stool was not a fixture but was mounted on a pair of wooden wheels so that it could be wheeled through the streets, and at the river-edge was hung by a chain from the end of a beam. In sentencing a woman the magistrates ordered the number of duckings she should have. Yet another type of Ducking-stool was called a tumbrel. It was a chair on two wheels with two long shafts fixed to the axles. This was pushed into the pond and then the shafts released, thus tipping the chair up backwards. Sometimes the punishment proved fatal, the unfortunate woman dying of shock.
Source: Wikisource

1911 Encyclopædia Britannica, Volume 8… (1911)

It was a strongly made wooden armchair (the surviving specimens are of oak) in which the culprit was seated, an iron band being placed around her so that she should not fall out during her immersion. Usually the chair was fastened to a long wooden beam fixed as a seesaw on the edge of a pond or river.
Source: Wikisource

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