Broadside NW: Time For A New Approach?
14 July 2007 by Tom Foord
We had a new recruit today, Emma Heron, who was keen for some digging action since her usual team of Eastwater and Daren diggers were all away on foreign expedition. Alan, Keith and I were keen to show her the delights of Aggy digging, but as it happens it turned out to be a bit of a baptism by fire.
We made our way to Broadside in 2h 50m, taking in the sights of Trafalgar Passage on the way. The objective today was to continue digging downwards in Broadside NW in search of a way on. ButÂ as weÂ started to dig we immediately discoveredÂ that this was not going to beÂ asÂ simple as we had anticipated.
Until now we have been digging down through dry mud which is easily broken up by a crowbar. But now we had hit a layer of extremely heavy clay of a dark reddish colour. This stuff is likeÂ plasticine, but harder, heavier,Â and less flexible.Â By continually hammering awayÂ at it with the pointy end of a crowbar, lumps of it could be slowly peeled off, but this was extremely slow and hard work. After several hours we had removed just 30 trays, some of which were only half full, and the effort was taking its toll on all of us.Â In addition the ‘arch’ feature we had been following down had again pinched out into a narrow crack, so things weren’t looking too promising. Time for a rethink.
The heavy clay we have hit is not a good sign, as this is not indicative of water flow. It either means we are in a dead end alcove, or perhaps, as Alan suggested, that we have just about reached the floor of the passage (we are, after all, well over 3 metres down!) This theory is also reinforced by the scattering of rocks we have now been finding within the fill. There is also no scalloping on the walls, despite there being some fairly good examples a few metres back down the passage. All the signs point to us being in the wrong place.
With that in mind, we contemplated a trial horizontal dig following the wall, either at the bottom of or halfway down the pit. But with the air starting to turn a bit nasty in the pit we thought it may be more sensible to try at roof level first. For the last half hour we dug across to the wall to the left just before the pit, removing loose sandy mud. In fact we found there were layers of very coarse grained sand here, indicatingÂ fast flowing water. This will be wellÂ worth pursuing next time, and the aim will be to follow the wall all the way around the end ‘chamber’ to get an idea of the trueÂ shape and orientation of the passage here.
In total we had removed a measly 43 trays of spoil on a 12 1/2 hour trip. Not great progress, but considering the conditions in the pit this was quite an achievement.Â At least we have opened up new options and have something to focus on next time. Broadside NW is not dead yet!