| Cost of | Projected |Cost per | in | Mile. | operation. | Plant. | progress. | ------------------------+-------------+--------------+-------------+-------- | Miles. | £ | | | | | |Tonnage.| | |strokes.| | |bucket. ---------------+----+-----+----+--------+---+---+--------+----+----+-------- | ft.| |in.|ft.| | ft.|ft. | in. Isaac.