Here’s a photo taken at the Foote Foundry in Fredericktown, Ohio around 1900. I was once told by a former Foote employee that their largest bell was 50 inches. The one at the left looks that big. Click photo to enlarge.
Well you can ‘nest’ bells by putting a larger bell over a smaller bell, but it has to be considerably larger and you cannot see the bell underneath. This is typically only used for long term storage or shipping.