Plug in level wall.

These plugs were in the footwall of the level at regular distances, perhaps every 30 yards or so. I have been told from a reliable source they are SPAD plugs, used for surveying and mapping the workings. SPAD = 'Survey point and Distance' ? Comments anyone?

This photograph is by NortonRay and was uploaded October 10th 2010. © NortonRay please do not copy or distribute without prior express permission.