A more thorough explanation:

A ducking stool is a device used in the past to punish scolds, bakers, and brewers. It involves repeatedly plunging them underwater as a form of correction. The device is also known as a castigatory, cucking stool, or trebucket.

The ancient Saxons referred to it as a "scealfing stole," and it was mentioned in the Domesday Book as a "cathedra stercoralis." The punishment was often carried out by dunking the offender into "stinking water" or a midden.

For example, if a woman was convicted of being a common scold, she would be sentenced to sit in the ducking stool. The stool would then be plunged into the water, and the woman would be repeatedly dunked as punishment.

The use of the ducking stool was eventually phased out as society moved away from physical punishment as a means of correction.