This inlet leads off below Myers' leap as a long low canal passage to a large lake chamber and twin sumps. The left hand one appeared to be the most promising and was the one dived on this trip. The sump is in character a continuation of the inlet passage, having many confusing oxbows, and in places the correct way on is far from obvious. 290 feet of line was laid to the bottom of a silt slope at -30 feet. This was ascended via a narrow rift to airspace in a tiny sump pool with a small stream flowing down from a narrow continuation. As exploration would have necessitated dekitting, the diver decided to redescend to -30 feet and search for the correct way on in the main water. Unfortunately, such were the quantities of silt disturbed by the ascent that the way on could not be located and the diver reluctantly returned to base. R.J.S. and J.T.G. then began the long haul to the surface with all the equipment and tackle. Quite a testing trip for two !
R.J.S.
Editor's note: The previous dive into this sump was by Wooding on 8.1.1966 (Review, 1966-67, 81). He had had the pot laddered previously and was supported by sixteen cavers. But his line reel containing 1000 feet of courlene was smashed on the way in and only 200 feet of it could be used. R.J.S. and J.T.G. did better by themselves.
R.J.S. kitted up with twin forties and dived to find that his line of 8.1.78 had become tangled and washed back. After some time sorting this out the previous limit (of 88m) was reached and all the old line successfully replaced. 15m of new line was laid and an ascent made to an airbell with a small inlet. This could well be the same as the one found on 8.1.78 but entered via a different oxbow. Proceeding from the airbell, a further 73m of line was laid and tied off in the floor at -9m depth. The passage is large and easy, but unfortunately due to time wasted sorting out the old line, the diver had reached air margins and had to return. According to the survey, this is only 107m away from the chamber in Little Hull Pot found on 29.12.79 (NL 55:12).
R.J.S.
The diver proceeded to his previous limit at 177m in good visibility. A further 9m of line was laid in a large bedding passage to a junction. Having taken a compass bearing and belayed the line back, the diver decided that the right hand branch looked the more promising and proceeded to explore it. 30m of line was laid in a smaller, more tubular passage, with breakdown on the floor, to an ascent to airspace from -9m. A rift type airbell was found with muddy walls, making a climb out of the deep water impossible. The aven looks to be about 9m high at least and the explorer could not see whether a passage leads off up there, but it looked quite hopeful. Returning to -9m, a search for a flooded continuation revealed no way forward, and so the diver slowly reeled back, searching for branch passages.
Eventually the junction was reached and the diver proceeded to explore the left hand branch. 15m of line was laid in a bedding type passage, which is more typical of this sump than the tubular right hand branch. Again, the base of a flooded shaft was reached at -9m, but this time the ascent became too narrow at -3m. Returning to the base of the shaft, a search round revealed no alternative way on, but it was noted that there were other possible ways upwards, which could be tried. However, the two-thirds margin had been reached, so the diver tied off to a lead block and returned to base. On the way back, a black space to the left of the line (going out) was noted, about 30m before the previous tie-off point and this could provide a continuation. Plan opposite page 20.
Radiolocation of the Hunt Pot Inlet sump using the C.R.O. "mole phone" was also accomplished on this trip. This has shown that the sump is nearer to Little Hull than previously thought; that is, provided the Little Hull survey is correct ! In view of this, it may be that the diver "overshot" the main inlet junction of the above dive.
R.J.S.
The diver was lucky to be invited to dive the sump at the end of the newly-discovered "Friday the Thirteenth" series. He was even luckier to be presented with a band of willing sherpas. The series, discovered by ULSA, leads off over the top of Eyrie Pot and is over 0.75 km long. The main passage, which gradually increases in size as it gains more inlets, is about 400m long and drops down a 6m free-climb and a 10m pitch to an inviting sump. This turned out to be 10 m long in two stages, and is an easy free dive. 40 m of walking passage emerges in a chamber with a couple of avens in the roof. The second sump is situated at the bottom of a 2 m climb at the end of the chamber. It was dived for 40m to an underwater boulder choke. This is in a rift leading upwards at a depth of 14m. The visibility in both sumps is notable for its "Greek-like" clarity, and evidently they have little to do with the main aquifer. The only exception to this is in the roof of the second sump, where at shallow depth a 1 m layer of peaty water in encountered. The sump is fed by a small percolation stream. Thanks to all who helped on a demanding carry. JTG.
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