It is sixty-six feet in circumference, composed of forty-five large stones, measuring seven feet in height, six in breadth, four in thickness, containing four perfect lodges [or cells] and one destroyed. The supposed entrance in it may be called a subterraneous passage, faces the East and measures fifteen feet in length, four feet two inches and a half in breadth from the inside of the two outward pillars or stones, in height two feet, each pillar being one foot nine inches and a half thick.