sentences:  In front of the furnace is at least one vertical shaft, now capped off, which leads down to a short tunnel which connects with the canal tunnel close to the wharf area.Additionally, a number of deep drains below these buildings probably link to the canal tunnel.The site is now occupied by Butterley Engineering, one of the successors to the Butterley Company, and noted for its involvement in the construction of the Falkirk Wheel.