Note 27 — Chapter V · Megalithic Monuments.

An examination of the megalithic monuments still standing enables us to judge of the difficulties with which their builders had to contend, bearing in mind the primitive nature of their tools. We have already given the dimensions of the stones forming the alignments at Carnac. Those at Avebury vary in height from about fourteen to sixteen feet, and in the Deccan is a tumulus surrounded by fifty-six blocks of granite of an even greater size. One of the slabs of the Pedra-dos-Muros (Portugal) is remarkable for its size; and the length of the table of a dolmen on the road from Loudun to Fontevrault is more than seventy-two feet long; that of the dolmen of Tiaret (Algeria) is some seventy-five feet long by a width of nearly twenty-six feet and a thickness of nine and a half feet. This extremely heavy block rests on supports rising more than thirty-nine feet from the ground.27