Took advantage of the high pressure drying out the gritty sandstone at Craigmaddie for a few hours bouldering before the skin could take no more. If anyone knows about Mason marks, have a look at the photo below and let me know what they mean. These marks are under the left sheep pen, next to (presumably) old quarriers' names 'A. Cairns' and 'J. Neilson'. I assume these guys, or colleagues, carved the mason marks onto the sheltered back walls of the caves, no doubt during long lunch breaks or wet days when they couldn't be bothered digging out the mill-stones.