I'm surprised they don't have a grave-witcher. A rod into a 100 year old wooden box wouldn't feel like there were anything there... and I know there are folks that can witch a grave, just as some can witch water. They are amazing. Can tell male/female, where the head is, etc. There are also those that can witch a house... tell where the door was, windows, etc., on a house that is no longer there... or visible to us, anyway. :-) Joanne