Two styles of vaulting

On the left is the delicate fan vaulting of Bath Abbey allowing a wide, almost flat roof. On the right the narrower "lierne" vaulting of St. Mary Redcliffe, Bristol, with its decorated "bosses."

Bosses

The boss is the round decoration where the lines of the vault meet. Those in St. Mary Redcliffe are intricately decorated with gold, though they can scarcely be seen from the ground.