sump in the high main. The pumps were driven by a nominal beam engine working the pumps directly: the first two stages were driven by the main beam, and the third stage by a subsidiary beam above the pump staple (C). The pit was known as a wet pit and the engine (capable of nine to ten strokes a minute) normally ran at about seven strokes a minute to cope with the water ingress; on loss of pumping the low main would flood within little more than a day from seawater percolating through the roof of the seam from the North Sea above it. Three miners from Hartley were amongst the death toll of an explosion at Burradon in 1860 because (explained the Durham Chronicle) "little work has been doing at Hartley colliery lately owing to an accumulation of water". At the time of the disaster, the high main had been worked out and was closed off; the yard seam was being worked, but only by a few men (and a pit pony); the workings in the low main seam at Hester Pit were being extended to meet those at the Mill Pit at Seaton Sluice; within the year it would have been possible to escape from Hester Pit via the Mill Pit. In the meantime, a staple was provided within which was a ladder; this allowed escape to the yard seam from the low main should there be a major inrush of water ("the only thing that was feared"). Disaster On Thursday 16 January 1862 the fore shift went on duty at 02:30. At 10:30 the same morning the back shift were taking over from the fore shift, so most men of both shifts were at the coal face. As the first eight men were ascending, the beam of the pumping engine snapped and fell down the shaft. Although much of the brattice was destroyed, the first part seems to have deflected the beam away from the cage. Other debris fell on the cage, snapping two of the four support chains. Four of the eight men fell; the others managed to cling on. The beam came to rest jammed in the shaft and other falling debris created a blockage deep between the yard seam and the high main. Rescue attempts One of the deputies, Matthew Chapman, had been on his way home when he heard the crash. Retracing his