No-one knows the purpose of the dragon's head which protrudes
high from the left hand wall of the nave.  One suggestion has it
that, because it is on a pivot and has a hole through its neck, it
was originally used as the mechanism for raising the font cover.
A chain would have passed through the hole and by raising
the dragon's head the font cover would be lifted
so that baptism could take place.

Get this image from alamy