Such are the menhir, the kistvaen, the so-called "sacred" circle, the stone rows, the hut circles, barrows, and cairns. All these abound on Dartmoor. Nowhere else in England can be seen such an extent of land undisturbed by cultivation, and carrying on its surface so many hoary monuments of a prehistoric population. It may be premised that all kinds of theories have been floated as to their purport and as to the period to which these relics belong, and the loudest and most positive have always been those who had no experience with spade and pick, which can alone solve the problem of their object and age. Systematic and persistent investigation into these monumental remains has been carried on for six years by a committee acting under the authority of the Devonshire Association for the Advancement of Science, Literature, and Art, and five reports of their proceedings have been already published in the _Transactions_ of the Association. It may be said that, at all events with regard to the hut circles, their position in the order of civilisation has been made out almost to a certainty, for something like a hundred and fifty of these have been carefully examined. With these accordingly we will begin. They are strewn in thousands over the surface of the moor, and such as remain are but the merest fraction of those that must have existed formerly, for incalculable numbers have been destroyed by those who have made enclosures. The hut circle is all that remains of the primitive dwelling of a people that were pastoral, and were clothed mainly, though not exclusively, in skins. The foundations of the circular dwellings are formed of blocks of granite, sometimes set vertically and sometimes placed in horizontal layers, enclosing a space from eight to thirty feet in diameter. The roof rested on the circular wall, which was never over four feet high, and was doubtless of wood covered with rushes, heather, or skins; a low doorway facing south or south-west gave access to the interior; and a hole in the apex of the roof served as chimney. The thorough exploration of the floors of these huts has resulted in the discovery of fireplaces, cooking-holes, and raised platforms of stones forming seats by day and beds at night, not so uncomfortable as it sounds, when covered with rushes and dry fragrant heather.