POMONA, or MAINLAND, an island, in the county of Orkney and Shetland; containing 16,141 inhabitants. This island, which is the largest of the Orkneys, is situated between the sound of Wire and other sounds, on the north, and Scalpa Flow, Holm sound, and other waters, on the south; and is about nineteen miles in extreme length and fourteen miles in extreme breadth, comprising an area of 150 square miles, or about 96,000 acres. It is divided into two unequal peninsulas by the bay of Kirkwall on the north, and the still deeper indentation of Scalpa Flow on the south. The surface is diversified with hills, of which those in the western peninsula are of greater elevation than those in the eastern, which is also considerably less extensive in its area. Of these hills, several are clothed with verdure almost to the summits, affording excellent pasturage for sheep; and between them are fertile valleys of a loamy soil; but the principal land under cultivation is along the coast, where abundance of sea-weed is obtained for manure. In the western portion of the island are some inland lakes, of which by far the largest is Loch Stennis, divided nearly in the centre by a boldly projecting neck of land, which forms a natural causeway reaching nearly to the opposite shore, and on which are the celebrated Druidical remains called the Stones of Stennis. The other lakes are Orphir, Skail, Birsay, and Aikerness, from which issiie several small streams abounding with different species of trout. The coast, especially on the west, is bold, rocky, and precipitous, rising into mural cliffs of considerable height, covered with sea-fowl of every variety, and perforated with natural arches leading into caverns of romantic appearance. The system of agriculture has recently made considerable progress, and the lands have been partially inclosed; the chief crops are oats, beans, and an inferior kind of barley. Great numbers of sheep are pastured on the hills, and attention is paid to the improvement of the stock, for which purpose rams of the Merino breed have been introduced: large herds of swine, also, are fed upon the commons. The island comprises the parishes of St. Andrew's, Birsay, Evie, Firth, Holm, Kirkwall, Orphir, Sandwick, and Stromness, all of which are separately described.