John Spence, Shetland Folk-Lore (1899)
“ But there is another and much more ancient broch at Seffster, Sandsting,—an underground one, and of a kind existing in several parishes in Shetland. They are often found in level fields, dug deep into the ground. These must have formed the earliest abodes of the Norsemen. They are quite different from the mound dwellings or earth houses. “The conclusion I have come to is that Shetland was inhabited by three successive and distinct races before the arrival of the Norsemen, and that the last of them, the Finns, built the brochs. ”
