There had always been some uncertainty as to whether the Engine shaft at Beckwith's mine had been filled or just capped. The truth was revealed in June of '96 when the Lands division asked the mines group to investigate a shaft that had opened.
It was the engine shaft. The fill had been sitting on a platform at a depth of ten feet which had given way dropping good style to a depth of 150 feet and stripping out the stone work, (ginging) for about twenty feet on the west wall.
Group member Simon Cooper investigated the conditions by making a descent to the bottom, landing on a huge pile of scallop shells at 150 ft. The shaft had apparently been used as a dump by a shellfish factory many years ago.