Greywethers

Greywethers, the name given to large blocks of hard sandstone, which are scattered sporadically over the southern and south-eastern parts of England. The name has probably been suggested by their resemblance in the landscape to sheep lying about. Other names by which they are known are Sarsden Stones, Druid Stones. They are as a rule roughly oblong, and are of all sizes up to 10 or 15 feet in length, and 2 or 4 feet in thickness; and are believed to be the relics of beds of Eocene age which formerly extended over all the region where they occur. These beds probably consisted chiefly of loose sand, &c., the greywethers representing concretionary portions hardened by siliceous cement, which have thus withstood the denudation that has swept away the incoherent deposits of which they once formed a part. The outer ring of monoliths at Stonehenge is formed of greywethers.