It began to be clear that this radiocarbon phenomenon was one that could be explained in this way in Europe with the fault lines that I mentioned earlier, and so I put together a table. I just used all the radiocarbon dates I could get from - from Neolithic and early Bronze Age Europe and put them in their correct stratigraphic positions on the table and then saw how that worked out. And it really did show that, for instance, the Megaliths of North Western Europe started at least 1,000 years before the pyramids of Egypt and before their supposed predecessors in the round tombs of Minoan Crete and it showed that metallurgy, copper metallurgy, got going far earlier in the Balkans than there was any trace of it at that time in the Aegean, and other things, like the Temples of Malta, found their place as also did the Wessex culture which wasn't as early as all that but it was going by 1800 BC and therefore well before Mycenae and Stonehenge certainly was clearly much earlier than Mycenae and nothing to do with the Mycenaeans. So that worked out quite well as a whole series of articles really and naturally caused controversy at the time. And then I wrote my book, "Before Civilization: The Radiocarbon Revolution and Prehistoric Europe", which was published in 1973, and that really tried to set out the whole thing systematically. But what became particularly interesting was not just the chronology which began to emerge and has been confirmed, but, okay, then if all these things are earlier than the pyramids or whatever, how did they do it? I mean that's why it was difficult to believe and, indeed, that's why people like Gordon Childe and predecessors of 100 years earlier, Oscar Montelius and so on, had said, well, we can't have these great chamber tombs being older than the pyramids. We assume that the pyramids are first and things diffused outwards including metallurgy and so on. And so if you say, no, the radiocarbon dates now show us that these phenomena, these tombs or this metal industry, is before the alleged predecessors in the East Mediterranean and the Aegean, then you have to sit down and say, well, okay, why and how - why were people building tombs - built tombs, in Ireland or in Brittany or in England or in Spain so much before anything like that was happening remotely comparable in Egypt or the Aegean? How come that people were producing copper objects in the Balkans and maybe in Spain before they were doing so in the Aegean? And so there were problems of culture process there really. I think the interest in my case then shifted from the chronology, which remained interesting but became established in outline and then became established in greater detail, the interest shifted to what one could call culture process and this harmonised very much with the interests in the United States where people like Lewis Binford were moving away from the culture sequence focus which people like Jimmy Griffin in Michigan had been emphasising and to start to look at the mechanisms of culture change. Why were these things happening earlier in one place than another? So that was, I think, where the interest was building up.