The little island of Mousa (the Mosey of the Saga), lying off the Mainland of Shetland, is interesting as containing the best preserved specimen of the “towers of defence,” which were the strongholds of the native inhabitants previous to the Norse invasion. [Illustration] The tower of Mousa, of which a view is here given, consists of a circular dry-built wall, 15 feet thick at the base, enclosing an area or circular court 30 feet in diameter, and open to the sky, so as to admit light to the ranges of windows which open from the galleries towards the interior. The doorway leading through the wall into this interior court is the only opening to the outside of the tower. From the court other openings in the wall give access to small ovoid chambers in the thickness of the wall on the ground-floor, and to a stair which ascends to the upper galleries. Above the chambers on the ground-floor the wall is carried up hollow, or rather there are two concentric walls with a space of about 3½ feet between them, which is divided into storeys or galleries by horizontal courses of transverse slabs, which bind the two walls together. Thus each of these courses of horizontal slabs forms the roof of the gallery beneath it, and serves as a floor to the one above it. These singularly-constructed towers were once thickly planted over the whole of the northern mainland of Scotland, as well as over the most of the Northern and Western Isles.[204] A number of them have been excavated of late years, and the results of these excavations[205] furnish us with interesting evidences of the conditions of life among the people who lived in them. The relics that have been obtained from them have no connection as a class with those that are usually found in the cisted graves and chambered tombs of earlier times.[206] But judging from the general character of their included remains, the people who lived in these towers were possessed of a considerable degree of civilisation. There is abundant evidence that they were not only expert hunters and fishers, but that they kept flocks and herds, grew grain and ground it by hand-mills,[207] practised the arts of spinning and weaving, had ornaments of gold of curious workmanship, and were not unskilled workers in bronze and iron. Their pottery was rude, but not ruder than the pottery manufactured and used for common or domestic purposes in some of the islands of Scotland within the present century. It is true that silver denarii of the Roman Emperors Antoninus, Trajan, and Vespasian, have been found in the outbuildings connected with the Broch or “Pictish Tower” of Lingrow at Scapa in Orkney; but it is to be noticed that upwards of 4000 of these Roman denarii have been found in Scandinavia, where the Romans never were, and found so often associated with relics of the Viking period as to suggest that they were carried thither some centuries after their dates.