Question

When was the tripods buried underground?

Answer 1

Legend has it the Lord Mayor of London made the requirement in June of 1665 that all graves by made at least six feet deep in order to limit the spread of the plague. To add on to this answer it my also be that every winter or spring when everything melted or the rain started to come the ground would get soggy and the water that seeps down in the ground would push the coffin up and out of the burial area