During the time of the Black Plague in Europe, bodies were not buried properly or as deep as they are today. These slovenly practices resulted in rather unpleasant side effects. As soil around the bodies eroded, body parts became exposed, which explains the origins of the slang term "boneyard" for a cemetery. Besides the grossness content, decomposing flesh on the surface of the earth did nothing to help the continent's health problems. England was the first to mandate the six foot-under rule, with the idea that husband and wife could be buried atop each other, leaving a safe cushion of two feet of soil above the buried body with the assumption that if each casket was two feet high, it would allow two feet for the husband, two feet for the wife and two feet of soil above the last burial. Another fact to remember is that the six-foot rule also puts coffins out of reach to most predators and the frost line!
