BASS ROCK, THE, a small island in the Firth of Forth, about 1 -m. from Canty bay, Haddingtonshire, Scotland, circular in shape, a mile in circumference, and 35oft. high.
On three sides the cliffs are precipitous, but they shelve towards the south-west landing. The Bass Rock is an intrusive volcanic mass of phonolitic trachyte or orthophyre like the eruptive masses of North Berwick Law and Traprain Law, but non-porphyritic. Sea-birds, chiefly gannets or solan geese haunt the rock in vast numbers. A lighthouse with a six-flash lantern of 39,00o candle power was opened in 1902. For a considerable distance east and west there runs through the rock a tunnel, about I 5f t. high, accessible at low water. St. Baldred, whose name has been given to several of the cliffs on the shore of the mainland, occupied a hermitage on the Bass, where he died in 756. In the 14th century the island became the property of the Lauders, called afterwards the Lauders of the Bass, from whom it was purchased in 1671 by the Government, and a castle erected in which many Covenanters were imprisoned. At the Revolution four young Jacobites cap tured the Rock, and having been reinforced by a few others, held it for King James from June 1691 to April 1694, only surrender ing when threatened by starvation. Thus the island was the last place in Great Britain to submit to William III. Dismantled in 1701, the Bass passed into the ownership of Sir Hew Dalrymple, to whose family it belongs.