29 August 2017

The dig is back on

We left the dig in a rather bad way the last time. At the very entrance, a big flake hung loose from the ceiling! We hoped it would come down on its own initiative before we would get back. As long as it was there, there wasn't really a safe way into the dig - at all. And it would be hard and scary to persuade it down!

When we got back I was down first. I immediately went to have a look. And I saw the flake was down! Success! It had snapped the electrical cable that had been suspended from it but that was a detail. And with that flake away we could go in for a closer look!

 The big flake down; notice the big metal ring to which the cables are tied. You can now see the back end of it sticking out on the other side. And notice the electric cable running behind it too, going up...

There clearly still was a big loose flake, but you could get around that. If you took the traditional way in you had to pass underneath, but there was another passage; it wasn't very comfortable but I decided to go in through there to go and get the metal bar and the crowbar from high up, so we could go and bring some loose stuff down. It's not good to hang around when loose bits fall on your head all the time! And you don't want things to come off in your hand or under your feet either, We had some tidying up to do! I threw Miles the metal bar and prodded the passage going up a bit, so the most offensive loose bits would be gone. I brought down a lot! Miles had really gone to town on the slate last time.

The flake that's still there, with Miles sticking his hand into the lower crack

When it all seemed OK I went to the far end where the crowbar was. I used it to clean up more. And I brought some loose rocks down that had been perched safely but had been dislocated. I didn't think we'd get much done beyond cleaning up!

We had a long, pensive look at the big flake. The good thing was that you could bring it down from the side; it could not fall onto you that way. Or slide towards you after coming down. But Miles was a bit nervous about it perhaps blocking the way out. I was a bit nervous about a vertical rock leaning against it; would that topple over if the flake went down, and bring godknowswhat down. Hm! We wanted to do that from a distance. But how? Miles had two ideas. Stay tuned! I hope we get to try them next week...

We had a tea break. At the end of it Miles showed me his altimeter; he had brough one so we could measure how much height we had gained. He set it to zero on the chamber floor. It obediently gave a level of 1m when he held it up, and 2m when he held it further up. Looked OK! But I had a polyprop rope so I could take a measure of horizontal distance too.

I climbed to the ceiling. The altimeter said it was 92 m up. Oh dear! It clearly wasn't. And I hadn't tied my rope to the bottom of the passage so I wasn't being very efficient. Oh well. I checked the angle of the ceiling with my compass (or tried; it's a bit of a faff if you're the only source of light around) and went on. At the far end I checked the altimeter still gave gobbledygook, took another ceiling measurement, and had a bit of a prod at the remains of the pile of rock there. I removed some more! And I noticed I might be able to dig under a big rock, rather than necessarily having to blow it up and go through. The problem was that the only place you could throw any rocks from there was in my own way, impeding the way out. If Miles could get up here he could help tidy up! But first things first.

I tied the rope to a rock. Then I went back to the vertical passage. From there I threw the rope to Miles and asked him to tie a knot in it at the bottom. Then we would have all the measurements needed! I went back to retrieve the rope. It was coming close to having-to-skedaddle-time. I came out and gave Miles his altimeter back. It now said I was at -105m! That thing needs calibration. Anyway. The polyprop rope would tell us enough!

We went out, and popped by the manager's office, where Miles' shoes were. There was also a measuring tape there! We measured the lengths of the two marked bits of rope. I had come less far than I thought! About 8m up vertically, and then 10m along the ceiling. Oh well, not bad anyway! 

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