"NORTHMAVINE, (or Northmaving), a parish in the Mainland, Shetland Islands, coast of Scotland. It comprises the northern part of Mainland, which is indented with many voes or inlets, affording safe harbours for the fishing-boats, and is surrounded on all sides with small islands, holms, and rocks, as Eagleshay, Lamba, Dorholm, Maiden Skerry, Hamnavoe, Burravoe, &c., but only one of these - Lamba - is inhabited. It is a peninsula united to the parish of Delting by a narrow isthmus about 100 yards broad at high water, called Mavis-grind, but so low that at high spring-tides it is entirely surrounded by water. It extends in length about 16 miles from S. to N., with an extreme breadth of about 8 miles."
From The National Gazetteer of of Great Britain and Ireland (1868)