Spellbound, I watched bromeliads hurtling past me as I clung to the brick-red sandstone face. I was trying to count the number of scorpions which accompanied the flora but swirling mist made this an impossible task. The rock was running with water and the south-east wind which was blowing across the rain forest, 3,000 feet below, was amazingly cold, despite the fact that we were only 5° 15’ north of the Equator.

Six feet above my head, Don Whillans stood like a statue on a ledge barely the width of his boot; his solid figure, clothed in an orange waterproof suit, gave to the place a comforting sense of reality. From above in the ghastly Bottomless Chimney came the distorted shouts of Joe Brown and Mo Anthoine. I knew they were having a desperate time, but we could do nothing to help. I was still badly shaken by ten of the worst minutes of my life, and as I hung on a microscopic ledge, I wondered what the hell I thought I was doing up there on the Great Prow of Mount Roraima – Conan Doyle’s ‘Lost World’. The partially severed rope with water streaming down it, up which I’d just climbed, did nothing to reassure me. Obviously, it seemed, my first instinct had been the right one.

That was back at home in Glencoe in October 1969 when I received a letter from John Streetly, an old climbing friend with whom I’d been on the North Face of the Grande Jorasses. John lives in Trinidad and I opened his letter with pleasurable anticipation. John never writes unless prompted by some exciting enterprise.

But at that time I was too full of plans to go to the Russian Caucasus to be able to work up enthusiasm for the sandstone towers with overhanging jungle tops depicted in John’s photographs. And anyway I’d heard terrifying tales of the wildlife, and visualised John’s mesas seething with deadly snakes.

Early in 1973 I had a visit from Julian Anthoine, whom everyone calls Mo. He was bringing me a glass fibre capsule which he had produced as a possible design for a new type of stretcher to evacuate injured climbers from high cliffs. Mo, who is thirty-three, is small and dark with an almost uncontrollable exuberance which has carried him all over the world. He is always getting in and out of scrapes and has, to say the least, a picturesque way of putting things and a bawdy sense of humour.

Mo told me that he was going to Roraima in Guyana, to tackle the Great Prow. Roraima’s summit marks Guyana’s border with Venezuela and Brazil. The Prow is an overhanging buttress of sandstone which would perhaps give the only possible access from Guyana to the country’s section of the summit. Adrian Thompson and Don Whillans were to be joint leaders of the party which was also to include John Streetly, Joe Brown and Mike Thompson, who had been on the Annapurna South Face expedition. It was obviously going to be a strong team. I offered Mo my condolences, however, for I still had a vivid picture of scorpions and spiders printed indelibly on my mind.

‘One thing, Mo,’ I said with conviction. ‘You wouldn’t get me there!’

At the time I hoped to go back to the south-west face of Everest with the Japanese expedition in the fall of 1973 and I wondered as I spoke to Mo which would be the most gruelling trip: the inhospitable wastes of that great unclimbed face of Everest with its rarified air and atrocious weather of the post-monsoon period, or the incessant rain and blood-curdling creepy-crawlies of the Roraima region.

Mo returned south to his climbing equipment business in Llanberis and a cold spring followed, during which I was working on a film on Buachaille Etive Mor in Glencoe for a television drama series called Sutherland’s Law with Ian Cuthbertson playing the leading role in a climbing murder story. Neil McCallum was the producer and had many years previously made Hazard, a climbing film set in the Dolomites, with Joe Brown.

Then I heard that the Japanese Alpine Club had decided not to invite Dougal Haston and me on their Everest expedition since recent history of joint expeditions had been, to put it mildly, disastrous. They were very apologetic about it and felt sure we would understand. We did! Dougal had been a member of the ill-fated International expedition of 1971 and I had been on the German expedition in 1973 with Don Whillans and Doug Scott. Both Dougal and I had climbed together on Chris Bonington’s expedition during the post-monsoon expedition in 1973 and were still keen to have another crack at that terrible, but fascinating face. It was not to be.

My old friend Don Whillans came up to Glencoe at the end of May, on his annual pilgrimage to the ‘tribes of the north’, as he calls us. This time he’d brought a caravan, an appendage of modern motoring for which I, in common with many Highland Scots, have an inborn hatred. Don, even after knowing me for many years, still believes I live on potatoes and porridge; on the other hand, I have to admit that I too am prejudiced, for I assume that he lives solely on beer and fags. He stopped outside my house, leaving his caravan parked by the side of the main road.

‘Ah thocht ye were oot, Jock,’ he said as he came in, then rapidly abandoned the unaccustomed dialect, ‘How goes it?’

‘Not bad, old fruit,’ I replied. ‘I see you have a mobile home these days –just in time to join the caravan Lemming Meet at Mallaig; they’re all going to drive off the pier.’

‘Your jokes are worse than ever,’ he spat out. ‘Where can I park the bloody thing?’

Kingshouse Hotel is always a congenial meeting place in Glencoe; particularly so during this period, since the BBC actors and crew had virtually taken over the whole hotel. Mo had met Neil McCallum there once, but on that occasion we hadn’t had an opportunity to discuss the expedition. Now Don came up with me one evening and met Neil, a Canadian by birth but a Scotsman by ancestry and inclination. Don, in his dry way, told us of his forthcoming trip to Conan Doyle’s ‘Lost World’.

‘Aye, we’ve got quite a bit of backing from the Government out there,’ he drawled in his broad Mancunian accent as he put down his pint of Tartan with deliberation. ‘It makes me suspicious. I think there’s a fair chance that the Venezuelans may send in a reception committee to welcome us with blow pipes.’

‘Why?’ I asked, my interest instantly roused. ‘Is there political trouble out there?’

‘Oh, aye,’ said Don. ‘I think there are a few fly moves afoot. There’s always been trouble with that ruddy mountain. You see, the Guyana bods can’t get to the top except through Venezuela and the Venezuelans aren’t that friendly.’

I remembered John Streetly telling me of a place where the top of a peak was covered in agates and so I asked Don if there was any chance of diamonds.

‘Tons of them,’ he replied. ‘It’s the second biggest diamond area of the world!’

I could see Neil’s interest was being roused and the diamonds certainly intrigued me – a throwback, no doubt, to a lot of futile prospecting I once did in New Zealand.

I hadn’t admitted it to anyone, but ever since Mo was staying with me in the winter, the Roraima expedition had been getting under my skin. Out of sheer perversity I had made a point of saying to several friends, ‘What a place to go! Goodness, it’s wet enough in Scotland but at least when it’s wet here we don’t get midges and tourists. There you get everything all the time.’

However, I hadn’t succeeded in fooling myself, as I quickly realised, listening to Don speaking in a monotone which, in any other person would have been extremely dull; but Don’s speech becomes compulsive listening, and makes him probably one of the most popular lecturers in the climbing world today.

‘Aye, we haven’t all that much brass,’ I heard him say to Neil. ‘It’s an expensive trip and we haven’t got round to doing much about raising any of the necessary.’