This is the actual Medieval bell which was rung on the night before executions in the City of London, to call the condemned to atone for their sins.
You can hear it rung in this short video here:
It is this bell which is thought to be "the bell of Old Bailey" which appears in the old English song, 'Oranges and Lemons':
This picture comes from the free public lecture (with recitals):
"Medieval Music: The Lands of the Bell Tower"
The lecture was delivered by Christopher Page, Gresham Professor of Music, as a part of his 2015/16 series of music lectures:
"Music, Imagination and Experience in the Medieval World"