Last month I went north, up the west coast of Scotland and out to the Western Isles. It was, as always, hauntingly beautiful – that smashed-up wilderness, fragmented first by the forces of nature and subsequently by the forces of capitalism (aka the Highland Clearances).I didn’t really go for that beauty though, it was just a bonus; I went to see the rocks dance. I don’t here mean the extraordinary way that the small islands along that coast appear to dance on the waves when it is sunny. I wanted to put my two hands on either side of the Moine Thrust, a dark line along the Knockan Crag, where Ben Peach and John Horne finally resolved a century-long argument and in 1907 proved (to almost everyone’s satisfaction) that rocks do move. Moine was the first scientifically