Next in importance to this is the circle at Stennis, about three-quarters of a mile distant. It consisted originally of twelve stones 15 to 18 feet in height. Only two are now erect, but a third was so not many years ago; and the fourth, of which now only a fragment remains, is represented as standing when the drawing, which forms the frontispiece to this work, was made.[274] The remains of a dolmen still exist within the circle, not however in the centre, but close to its side, one of the stones of the circle apparently acting as head-stone to it. Beyond the stone circle which measures 104 feet in diameter is a ditch 50 feet wide, making the whole diameter of the monument to the outward edge of the surrounding mound about 240 feet. Not far from this circle, and close to the bridge of Brogar, stands a single monolith 18 feet in height, which is the finest and highest stone of the group; and in another direction a lesser one, with a hole through it. Though only 8 feet high, 3 feet broad, and 9 inches thick, this stone has become more famous than the others, from the use Sir Walter Scott makes of it in the 'Pirate,' and because, till a very recent period, an oath taken with hands joined through the hole in the Stone of Woden, was considered even by the courts in Orkney as more than usually solemn and binding.[275] [Illustration: 84. Circle at Stennis. From Lieutenant Thomas's plan.] No excavations, so far as I know, have been attempted in the circle of Stennis, but its ruined dolmen is probably sufficient to attest its sepulchral character. Some attempts at exploration were made in the larger Ring at Brogar, but without success. This is hardly to be wondered at, for a man must feel very sure where to look, who expects to find a small deposit in an area of two acres. The diggings are understood to have been made in the centre. There, however, the ground looks very like the undisturbed surface of the original moor, and as if it had never been levelled or used either for interment or any other human purpose, and slopes away irregularly some 6 feet towards the loch. My impression is that the deposits, if any exist, will be found near the outer circumference of the circle, either at the foot of the stones as at Crichie, or outside the ditch as at Hakpen or Stonehenge. In the smaller circles the diameter of which does not exceed 100 feet, the deposit seems either to have been in the centre; or, if at the sides, the stones were so arranged as to mark its place. In the larger, or 100-metre circles, we have not yet ascertained where to look. Accident may some day reveal the proper spot, but till it is ascertained either scientifically or fortuitously, no argument can be based on the negative evidence which our ignorance affords.