I then had developed this… this very great interest in archaeology and palaeontology, and so going out on these camps had become a regular thing, and in fact I went… in 1947, I went on an expedition with a man called Bosazzar and another man called Ray Adie, both of whom were geologists. We went on an expedition to the Kalahari Desert and it was… and I had been there before to parts of this, but actually I wrote a scientific paper on this… on the whole idea that there were these desert cycles in Africa which… which were most important for how the whole development of this thing, and that these were correlated, basically, with the cycles – the glacial cycles that were better known in the north…

[Q] So you learnt geology too?

Yes, I learnt geology. In fact I learnt quite a lot of geology. In fact, I'd become quite an expert on it and did later… and in 1947 or '48, I can't remember, when a big expedition came out from the University of California who wanted to see all the sights, I went with them and I went essentially as a guide, and that's where I met – because they'd asked him to go – Alex du Toit. Alex du Toit, as it would be called in French, but du Toit as we called it, was one of the most remarkable people. He is the… one of the great inventors of Gondwanaland, he's… with Wegener, and his book, The Geology of South Africa, of which I have a copy, is in fact the whole of the idea of the wandering continents, and he had come to the conclusion of geology alone that Africa and South America were once joined up. Now, he had a most remarkable life. He was already quite an old man when I met him, and he had gone out to survey the Kalahari Desert – which is where we went – as a young man for the geological survey in about 1890. In fact, the geological maps were the ones he made. And he turned up there dressed like, I would say, a Dutch Reform Church preacher. He was dressed in a black suit with a waistcoat and a tie and a hat. Now, all the Americans had come out you know, in expedition outfits with… with bush hats with little leopard skin rings. I had come out in my thing, which was shorts and boots and a shirt and a hat because we wore this, but du Toit had come there dressed in this beautiful suit. And I remember that one wonderful thing that happened on this trip was we were going along a road in the Kalahari Desert, in the middle of nowhere, and the people were asking about water divination, so he said he believes in it. So they said, 'You, a scientist; you believe in water divination?' He says, 'Yes'. He says, 'Just stop the car here'. He says, 'I'll show it to you, prove it to you'. So stop the car apparently in the middle of nowhere, and he gets out of the car and he cuts a branch, and he goes about… does this sort of tremendous amount of formality and ritual, and then he walks along the road and the thing bends. And he says, 'Well', he says, 'this means there must be water somewhere, so there should be a fault line somewhere here, and if we just go off down here, let's go and look for it'. And sure enough, we go down there and there's this thing, which… there's a little… little spring there – it had dried up, but you could see there had been a spring there. So all these Americans were amazingly impressed by this. And when we were going back, he started to tell me in Afrikaans how he came through here as a young man in about 1890 on an ox wagon doing… making the geological survey of this region and that he had found the spring here and that he recognised the topography of the land while we were talking. So I found this to be very amazing thing. However, he had a… this gives one an eye for country. It gives one an eye that one can look at a… at… at the topography and see its history in it. And of course, as you may imagine, this was threatening to become another profession and so I decided to give it up. And a colleague of mine who was one year behind me, Philip Tobias, he decided that he would continue it and I've always enjoyed it as a hobby; I've always enjoyed… I've just enjoyed the idea that one can go out and look at a country and of course extract its history from it, and of course that's another interest of course I've had in astronomy.