Bell in a mausoleum

[Michael Royalton-Kisch]

Passing through Brompton the other day I took a look at the Mausoleum in the 
cemetery there, and in one of them there was a sizeable bell with cannons 
(about 12cwt) on the floor surrounded by the shelves with coffins. Does 
anybody know anything about it? I thought perhaps there would be some clues 
in the plaque above, if there was a ringer in the family, but there 
wasn't...