The following day, I climbed the Corbett, Ben Dronaig, where I loafed about and read in the sun for 2 hours, then walked south up the track to camp at the high point 500 metres above sea level (grid ref NH042321). I was pitching my bivvi tent just next to the track that leads to Iron Lodge at 7.45pm when I heard from deep in the earth a faint but definite grinding noise, followed almost instantly by a sustained rumbling vibration. The whole thing was over in 5 seconds.

You can imagine my excitement and initial alarm. I knew there were geologically active areas around and my instant reaction was ëthatís an earthquakeí.  Two thoughts followed almost at once. First I had a picture of the earth swallowing me up; my rational mind instantly self-flicked this to fast rewind: this was not California. Second, I downgraded the event to blasting at some unknown quarry: why should I be so lucky as to experience an earthquake? I then asked myself whether I had even imagined it, but another, slightly smaller tremor followed two minutes later. I felt it but this time heard no noise. But this aftershock convinced me, and subsequently I was in a state of high glee and excitement. There was a second aftershock at around 10 pm which was so faint that it could only have been picked up by someone lying on the ground as I was.

I canít say much more about the actual earthquakes. Each was over quickly. The drama was in my solitary and remote location rather than the quake itself. Subsequently I checked out a website (www.gsrg.nmh.ac.uk.recbrit.html) which is full of interesting stuff, and this confirmed that I had felt the effects of three earthquakes in the locality of Sheil Bridge, of 2.3, 2.0 and 1.4 on the Richter Scale. Looking at a geology map, I saw the Strathconan Fault shown as a major feature, with Iron Lodge on or very near the fault line. 

I am geologically blessed. Twenty two years ago, in Bellingham, Washington State, where I was on holiday,  huge explosive bursts in the sky drove us out of the house in fear, and some Americans to their nuclear bunkers.  We could see nothing.  Someone sensibly switched on the radio. Mount St Helens had blown twenty minutes earlier.  We were two hundred miles to the North. A week before I had stood on the summit of Mount Hood (11,235 ft), on the Oregon border.  Black belching smoke rose from the then unerupted Mount St Helens some thirty miles away. ìErupt nowî, we wished in our ignorance.

Ten years before that, in 1970, I climbed to within 1000 ft of St Helenís summit, then a cone of perfect whiteness. High wind made the summit unreachable. We camped by Spirit Lake, an oasis of calm blue water and scenic splendour. After the 1980 volcano I travelled back to Oregon by train, and saw the havoc caused by the near emptying of Spirit Lake. Houses were lying stranded in mud, miles from their origins.  Great swathes of farmland had vanished, with fences marching into black sludge, like stone dykes from former fields vanish into reservoirs. It is all etched on my memory.

And now, so is the Shiel Bridge earthquake. It had been a great couple of days walking: hearing the tremor was the high point of a beautiful evening.