the , of which he writes there were only five (and thus possibly meaning the Inner Hebrides) and . is cognate with the Early Celtic dumnos and means the "deep-sea isle". Pliny probably took his information from Pytheas of Massilia who visited Britain sometime between 322 and 285 BC. It is possible that Ptolemy did as well, as Agricola's information about the west coast of Scotland was of poor quality. Breeze also suggests that might be Lewis and Harris, the largest island of the Outer Hebrides although he conflates this single island with the name "Long Island". Watson (1926) states that the meaning of Ptolemy's is unknown and that the root may be pre-Celtic. Murray (1966) claims that Ptolemy's was originally derived from the Old Norse , meaning "isles on the edge of the sea". This idea is often repeated but no firm evidence of this derivation has emerged. Other early written references include the flight of the Nemed people from Ireland to Domon, which is mentioned in the 12th-century and a 13th-century poem concerning , then the heir to the throne of Mann and the Isles, who is said to have "broken the gate of ". means "the plain of Domhna (or Domon)", but the precise meaning of the text is not clear. In Irish mythology the islands were the home of the Fomorians, described as "huge and ugly" and "ship men of the sea". They were pirates, extracting tribute from the coasts of Ireland and one of their kings was (i.e. Indech, son of the goddess Domnu, who ruled over the deep seas). Geography The islands form an archipelago whose major islands are Lewis and Harris, North Uist, Benbecula, South Uist, and Barra. Lewis and Harris has an area of and is the largest island in Scotland and the third-largest in the British Isles, after Great Britain and Ireland. It incorporates Lewis in the north and Harris in the south, both of which are frequently referred to as individual islands, although they are connected by land. The island does not have a single name in either English or Gaelic, and is referred to as "Lewis and Harris", "Lewis with Harris", "Harris with Lewis" etc. The largest islands are deeply indented by arms of the sea such as Loch Ròg, Loch Seaforth and Loch nam Madadh. There are also more than 7,500 freshwater lochs in the Outer Hebrides, about