Calcined tap cinder called 'bull dog' when used for the bottom of a puddling furnace, burnt in a kiln at Ebbw Vale, 1865, according to Barrows and Halls patent
Calcined tap cinder called 'bull dog' when used for the bottom of a puddling furnace, burnt in a kiln at Ebbw Vale, 1865, according to Barrows and Halls patent