In 1882-4, Frances Groome's Ordnance Gazetteer of Scotland described Gairsay like this:
Gairsay, an island of Evie and Rendall parish, Orkney, 1¼ mile E of the nearest part of Orkney mainland, and 1½ NW of Shapinshay. It measures 2 miles in greatest length, and 1½ mile in greatest breadth; consists chiefly of a conical hill of considerable altitude; rises steeply on the W side; includes, on the E and on the S, some low, fertile, well-cultivated land; contains, close to the S shore, remains of a fine old mansion, once the seat of Sir William Craigie; and has a small harbour, called Millburn, perfectly sheltered on all sides, mainly by Gairsay itself, and partly by a small island in the harbour's mouth. Pop. (1851) 41, (1871) 34, (1881) 37.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Gairsay has changed, please see our redistricted information for the modern district of Orkney Islands. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Gairsay and units named after it.
GB Historical GIS / University of Portsmouth, History of Gairsay in Orkney Islands | Map and description, A Vision of Britain through Time.
Date accessed: 21st May 2013
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