Dartmoor, an upland tract in Devonshire, situated between Okehampton on the north, Moreton-Hampstead on the-north-east, Ashburton on the south-east, and Tavistock on the south-west. Its length, north and south, is 22 miles½ its breadth about 20 miles, its area about 130,000 acres, and its mean elevation about 1700 feet. The greater part of it was afforested by King John under the name of Dartmoor Forest, given by Henry III. to his brother Richard, Earl of Cornwall, and annexed in the time of Edward III. to the Duchy of Cornwall. It consists entirely of granite, has a wildly hilly, rugged, shattered surface, and embosoms a great morass, whence issue the rivers Dart, Teign, Tavy, and Taw-Multitudes of its summits are rocky peaks, provincially called tors, many of them fantastically outlined, looking like ruined castles or uncouth animal forms, four of them respectively 2050, 1792, 1549, and 1203 feet high, and no fewer than 150 mentioned by name in a note to Carrington's poem of " Dartmoor." Micaceous iron ore and stream tin occur, and peat fuel is dug. The antiquities and the natural history are extensive and interesting, and have been described in Rowe's " Perambulation of Dartmoor," published in 1848. A large war-prison was built in 1806 on an elevated spot under Tor Royal, converted afterwards into a factory for naphtha, ammonia, and other products from the bogs, and changed subsequently into a place for convicts. Considerable additions were made to the buildings in 1874 by the-convicts, and further extensions have since been made.
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