<I think these things - I call them 'seams and shoulders' have been chipped out. On a tough sandstone they don't weather much. The orthodox view is that they are natural and caused by free rocks scratching against each other in the glacial drift. Look in the 'terminus' of the groove for a small carved feature that looks like nostrils.>

There is definitely something here, whether 'natural' or otherwise. Working from the top right and heading counter-clockwise, there is a quite pronounced groove which curves downwards and begins to come back up defining a 'face'. This 'face' stands about 4 inches proud from the beginning of the 'spiral'. The top of the curve is definitely natural but as it heads downwards becomes less defined. Touching the 'face' there was an indentation where the 'spiral' should terminate. I reckon someone with more experience should check it out. Wonder who that could be…