The plain truth is that the period I study is the 16th century, and they were absolutely obsessed with witches and spiritual beings.
When I was a kid a growing up in Ontario, Canada, Lake Erie was so polluted, I never thought it would ever, EVER be turned around where they could start cleaning it out in my lifetime!
As the work proceeded we found that the western end of the cutting receded under the slope of the rock, and thus was partly roofed over by the overhanging rock.