On Sunday we cleaned up around the complex joint found in the large beam, revealing the transverse mortise and the longitudinal continuation of the joint which has cut away the rear half of the beam over a distance of about 300 mm. The picture shows the joint as revealed, and also shows the remains of a very decayed piece of timber aligned with the joint in the beam and which has the remains of a small square cut mortise joint. The beam, some 290 mm square, shows some variation in its width over the short section revealed in the pit. These details are shown in the accompanying photograph; tcablogmaster apologises for the appearance of his knee in the lower left of the picture!
We augured into the north wall of the pit and encountered more timber from which we conclude that the beam continues to the north and we need to search further for its end.