Conversation so far:
who did our lady of knock appear to
First to see the vision of Our Lady of Knock were Mary Beirne and Mary McLoughlin, housekeeper to Knock parish priest Archdeacon Bartholomew Cavanagh.
how many people witnessed the apparition of our lady of knock
In the village of Knock, 15 local people saw the apparition of Mary, St Joseph, St John the Evangelist, and a lamb standing on an altar before a cross
when did the apparition of our lady of knock happen
The apparition of Our Lady of Knock happened in the evening of Thursday, 21 August 1879 at about 8 o'clock

Question: what did the witnesses do
Self-contained rewrite: what did the witnesses of the apparition of our lady of knock do