[a. Cornish bal ‘collection of mines.’] Also 6–7 ball. A mine. Attrib., as in bal-girl, -work.
c. 1600. Norden, Spec. Brit., Cornw. (1728), 45. Godolphyn ball.
1678. Phil. Trans., XII. 951. Godolphin Ball is the most famous of all the Balls or Mines in Cornwall.
1812. Ann. Reg., 52/1. Bal girls, as the girls are called who work about the mines.
1851. Kingsley, Yeast, xiii. 252. He could not stand the bal work.
