The old lady is at risk of being accused of witchcraft! She has a black cat as a pet. These, plus other creatures to be found in her cottage, were thought to be 'familiars' of the devil.
The poor lady in the background has been found guilty of performing black arts. She is being given quite a light punishment though - a ducking. Tied to the ducking stool she is being dunked in the local pond. Often witches were thrown in. If they floated they were guilty, and burned at the stake, or hung. If they sank they were considered innocent - but they had probably drowned anyway!
Ducking stools were also used as punishments for women who gossiped or scolded their husbands.
Wife beating was an accepted way of keeping one's wife in order !