Butterley Company correspondence file on the Low Main seam at Denby Hall Colliery, including plans Includes references to a sublease to the Denby Iron & Coal Company and to a share owned by W. E. Harris. Copy of coloured plan showing the Furnace coal seam at Denby Hall estate proposed to be subleased to the Denby Iron & Coal Company Ltd, early 20th cent. Annotated and coloured copy of plan showing the Furnace coal seam at Denby Hall Estate proposed to be subleased to the Denby Iron & Coal Company Ltd, with corresponding index schedule, early 20th cent. Plan showing area of Low Main coal seam proposed to be leased by the Butterley Company to the Denby Iron & Coal Company, early 20th cent. Plan showing area of Low Main coal seam to be leased by the Butterley Company to the Denby Iron & Coal Company, early 20th cent. Jun 1907-Nov 1910