On Sunday March 22nd 1959, Oscar Hackett Neil Moss, a 20-year-old student of philosophy at Balliol College Oxford, joined members of the British Speleological Association exploring Peak Cavern near Castleton in Derbyshire. The aim of their expedition was to go through Pickering Passage to the then known limits of the system and investigate a newly discovered fissure in a side chamber.
Access in itself was challenging. This involved negotiating Mucky Ducks, a tight, wet narrow squeeze beyond the end of the show tunnel which, after rain, often filled with water. This then opened into Boulder Passage, an easier section, but one that still required the potholer to negotiate a series of irregular obstructions. High to one side, above a steep, muddy scree was Pickering Passage, a long narrow crawl that was traversed partly on the knees and partly at full length. This ended in an awkward bend and muddy sump. Above it was The Eyehole through which it was only just possible to squeeze a human body. Finally, after a thigh deep muddy pool they arrived at the destination chamber and the intended fissure.
On reaching it the party dropped an alloy ladder down and Moss clambered and slithered his way into the unknown. He was not belayed as it was thought that the narrowness of the fissure would prevent him from sliding down. Shortly after 4pm he came to a corkscrew twist, which, having successfully negotiated, gave him access to the remainder of the shaft. On reaching this final section it is believed that he discovered a boulder that prevented further progress. However, as he could not manage to dislodge this and he could not move within the confined space, a light hand line was lowered down to him to assist his return. Unfortunately, this line was not strong enough to lift him and, although Moss managed somehow to tie himself to it, on at least three occasions it snapped.
This may well have caused him to panic and, as he tried to climb upwards, he became irretrievably stuck just below the corkscrew. He could neither bend his legs to get purchase on the ladder not flex his elbows to pull himself up the next few vital inches.
At this point the build up of carbon dioxide within the fissure started to take effect and by the time a stronger rope had arrived he was unconscious and so unable to fasten it around himself. Despite the valiant attempts of rescuers, his body could not be moved. He never regained consciousness and his death was announced on the Tuesday morning. His father, anxious that no further lives be endangered in recovering his remains, requested that his body was allowed to remain in-situ.
There were thoughts about recovering it at a later stage, but although it was at first felt that this was technically possible, many rescuers believed that this would have been unfair to his family who had resigned themselves to not seeing him again. Partly in fairness to them the fissure was sealed and subsequently an inscription was affixed close to it. The small access area is now known as Moss Chamber.
Several issues were raised during the subsequent inquest. One concern was that there was a lack of accurate feedback to the hungry press. One paper reported that it was intended to send a frogman down and push him up from below (a totally impossible feat). Another reacting to a comment that "only a superhuman midget could reach him" contacted the smallest British female potholer and took her by car to assist. The effect was spoilt however by publishing a picture of her dressed as if she were off on a Sunday outing! Other newspapers announced a successful rescue had been affected and Moss had returned home safe and well. This fact caused some rescuers to return home and others not to arrive for over 24 hours.
The sealed fissure is part of Peak Cavern, which lies below Peveril Castle, Castleton, Derbyshire.