ORKNEY ISLANDS, group forming a county off the north coast of Scotland. The islands are separated from the mainland by the Pentland firth, which is 64 m. wide between Brough Ness in the island of South Ronaldshay and Duncansbay Head in Caithness-shire. The group consists of 67 islands (not including rocky islets) of which 29 are inhabited, four of them only with lighthouse attendants. They measure so m. from north-east to south-west, and 29 m. from east to west, and cover acres. Excepting on the west coasts of the larger islands, which present rugged cliff scenery, the group lies somewhat low and is of bleak aspect, owing to the absence of trees. The islands are built up wholly of Old Red Sandstone. The Old Man of Hoy is a fine stack of rock standing detached from the north-west cliffs. The only other islands containing heights of any importance are Pomona, with Ward hill (88o f t.), and Wideford (740 ft.) and Rousay. Erratics of distant origin (e.g., from Moray firth) give evidence of glacial action. Nearly all of the islands possess lakes, the largest being Loch Harray and Loch Stenness in Pomona. The rivers are merely streams. Excepting on the west fronts of Pomona, Hoy and Rousay, the coast-line of the islands is deeply indented, and the islands themselves are divided from each other by straits, generally called sounds or firths, though off the north east of Hoy is Bring Deeps, south of Pomona is Scapa Flow and to the south-west of Eday is the Fall of Warness. The topograph ical names are Norse, and the common terminal of the names of the islands, a or ay, is the Norse ey, meaning "island." The islets are usually called holms and the isolated rocks skerries. The tidal currents, or roost (as some of them are called locally, from the Icelandic), off many of the isles run very fast and whirlpools are frequent.
sionaries, companions of St. Columba, followed about 565. As the Norse pirates made raids on Norway from the islands, as well as on Scotland, Harold Haarfager ("Fair Hair") subdued the rovers in 875 and added the Orkneys and Shetlands to Norway. They remained under the rule of Norse earls until 1231, when the line of the earls became extinct. In that year the earldom of Caith ness was granted to Magnus, second son of the earl of Angus, whom the king of Norway apparently confirmed in the title. In 1468 the Orkneys and Shetlands were pledged by Christian I. of Denmark for the payment of the dowry of his daughter Margaret, betrothed to James III. of Scotland, and as the money was never paid, their connection with the crown of Scotland has been per petual. In 1471 William, earl of Orkney, exchanged his earldom for lands in Fife, and the islands were annexed to the Scottish crown. In 1581 Lord Robert Stewart, natural son of James V., was created earl of Orkney, but in 1615 the earldom was again annexed to the crown. The islands were the rendezvous of Mont rose's expedition in 1650 which culminated in his imprisonment and death. In 1707 the islands were granted to the earl of Morton in mortgage, but in 1766 his estates were sold to Sir Lawrence Dundas, ancestor of the earls of Zetland.
In early times both the archbishop of Hamburg and the arch bishop of York disputed with the Norwegians ecclesiastical juris diction over the Orkneys ; but ultimately the Norwegian bishops, the first of whom was William the Old, consecrated in 1102, con tinued the canonical succession. The see, left vacant on several occasions, was finally abolished in 1697, although many of the clergy refused to conform. The Norse tongue, at last extinguished by the constant influx of settlers from Scotland, lingered until the end of the 18th century. When the islands were given as security for the princess's dowry, there seems reason to believe that it was intended to redeem the pledge, because it was then stipulated that the Norse system of government and the law of St. Olaf should continue to be observed in Orkney and Shetland. Thus the udal succession and mode of land tenure (or, that is, absolute freehold as distinguished from feudal tenure) still obtain to some extent, and the remaining udallers hold their lands and pass them on without written title.