Lathkill Head Cave - Alan Brentnall
Half a dozen met at the layby at the head of Lathkilldale for a trip into Lathkill Head Cave via the upper entrance. It was a wet night after a pretty wet day, but we still expected the recent good weather to have left the cave devoid of any stream, and we were not disappointed. However, water in the lower Tigers must still have been sumped somewhere as the QRAE II meter we were using started alarming as soon as I abseiled down into the Waiting Room. 18.2% (oxygen by volume) was the reading.
When the water flows through Lathkiller Hall, there is usually fairly good air in the system, as the stream acts like a pump, taking the old air out with it. When the stream stops running, the carbon dioxide builds up, and will continue to do so until the pools which sump in the lower reaches of the cave dry out. Once all the members of the group were down and de-kitted, we proceeded down through the climbs in the boulder choke to Lathkiller Hall. No stream, and 17.7% oxygen.
After a discussion, we decided that it would be pointless heading downstream, so all but one of us set off into Tiger 4 with the intention of going as far as the Emporium. After the strenuous "down-and under" squeeze, which had most of us panting quite a bit, the air readings had dropped to 17.6% and stayed at that level until we got to the junction with the Emporium route.
Carefully (one-at-a-time) we ascended through the crazy boulder choke into the beautiful chamber. Several present had never been this far, some hadn't even been in this cave, but we all appreciated the beautiful formations. We certainly appreciated the extra 0.5% by volume oxygen in the higher chamber!! One-by-one we retreated down the climb and out through the crawls to where Pete had spent a lonely 45 minutes building a miniature dry stone wall. The way out through the cave was slow but straight-forward, with no mishaps. And it was still raining when we surfaced into the warm night.