Tim Davies, Librarian at North Lincolnshire Council and a specialist in local studies,  explores the local folklore stories collected Ethel Rudkin and others. 

Boggart — creatures whose sole existence is to play tricks and cause trouble for people. They can be mischievous, frightening, and even dangerous, and they are very difficult to get rid of. Boggarts also tend to punish those who offend them and in some cases are trying to punish a human for injustice. Household boggarts can cause things to disappear, milk to sour, and dogs to go lame. Boggarts thought to live in marshes or swamps caused the disappearance of children.