This section is from the book "Ancient Legends, Mystic Charms, And Superstitions Of Ireland", by Jane Francesca Wilde. Also available from Amazon: Ancient Legends, Mystic Charms, And Superstitions Of Ireland.
Place two keys on a sieve, in the form of a cross. Two men hold the sieve, while a third makes the sign of the cross on the forehead of the suspected party, and calls out his name loudly, three times over. If innocent, the keys remain stationary ; but if, guilty, the keys revolve slowly round the sieve, and then there is no doubt as to who is the thief.