Gildas seems to have had an association with bells, possibly as a bellmaker. In his 12th C. Life* (Translation) Gildas tries to give a bell which was coveted by St Cadog to the Pope, but it won't ring for him. The Pope tells Gildas to give the bell to Cadog, and it rings when he does. The bell appears to have had the power that those who swore (on it?) illegally would be struck dumb, and evil-doers would confess their crimes.