The Address Book: Our Place in the Scheme of Things. Tim Radford

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СКАЧАТЬ sediment that speaks of entirely different conditions: of a huge, wandering delta landscape, of marsh, meanders, oxbow lakes and seasonally flooding rivers that would dry up and exist only as trickles, built up by silt from the mountains further inland, and then occasionally swept away again as the sea invaded, leaving its signature in the form of raised beaches.

      These beds, too, extend hundreds of metres downwards: their rock is now the Weald of Kent and Sussex, and they represent a long overture, a prelude, a period of marsh and mudflat, water meadow and tidal estuary, beach, dune and delta. Through this well-watered, fertile silt stalked iguanodon and baryonyx, and above them flew pterosaurs. Elsewhere in the world, Tyrannosaurus rex was already on the prowl; ichthyosaurs and plesiosaurs hunted in the shallow seas. So the Cretaceous period is marked by episodes of high and low water, of violence and movement. The modern world had begun to take shape: the Atlantic had begun to open, and Africa had begun to close in upon what would become the Mediterranean, to start pushing up the Alps. The extended ripples of that impact would gently uplift the chalk and shape the contours that would one day become the Downs, and the sediments that would form the Weald. Western Europe might be partly or entirely submerged, but at intervals fragments of Britain and Brittany must have been visible high above the waves: Wales was a rocky island, and so was something that would one day become Cornwall. The Pennines stood proud, and there was once an East Anglian massif – yes, marvel at the mountains of Norfolk, now at sea level and sooner or later to be submerged – that towered above the submerged Wessex basin. This exposed rock was sheathed not just with the implacable green of fern and cycad and moss: it sported splashes of bright colour. Vegetation had begun to change, and with it the fauna of fields and forests.

      The ancestors of modern butterflies and moths, the first ants, the first aphids, grasshoppers and gall wasps appeared during the Cretaceous, and so did the first flowering plants. The grasses will not emerge for aeons, but petals, pistils and pollen have begun to evolve and flowering plants to speciate in precise step with a new generation of pollinators, predators and scavengers. Chalk flowers such as eyebright and scarlet pimpernel have their roots in the Cretaceous, metaphorically as well as literally, and the comma butterfly is a kind of lepidopteran punctuation mark in a long story that begins with the chalk.

      But this accidental epic contains another narrative, one from which the history of human science and technology grows. At intervals in the chalk are puzzling inclusions called flints. Chalk is soft, flint is hard; a lump of chalk can be of any size or shape, but flints are knobbly, uneven things usually measured in centimetres or tens of centimetres. The exterior of flint is white: it takes its colouring from the carbonate of lime in which it is found. The interior however is dark: it is a concretion of silicon dioxide, also known as quartz, and also known as silica. There is no satisfactory explanation for the existence of hard nodules of flint in soft chalk, but the long-standing conjecture is that these too begin with submarine biology: they could have been formed from the siliceous remains of Cretaceous sponges that once grew in clumps on the seafloor. Flints are exposed with every ploughing, and they became the raw material for the walls, barns and homesteads of old settlements in the Sussex Downs.

      Flints also provided western Europe’s first systematically exploited cutting-edge technology, its first tool of mass production, the Neolithic equivalent of the Swiss army knife. Bang a flint with something very hard, and you flake a fragment from it. Keep on doing that, and you can turn a nodule of flint into an axe, an adze, an awl, a chisel, a knife, an arrowhead, a spear point, a sickle, a razor, an item of barter or even a tool for mining yet more flints. Five or six thousand years ago, late-Stone-Age humans systematically dug a series of shafts and galleries in the chalk near Spiennes in Belgium, and excavated on an industrial scale huge quantities of flints that could be worked and then traded for goods from other locations. Simply to work the mines, get the product to the surface and then exploit its potential value, these Neolithic entrepreneurs had to be aware of the market pressures of supply and demand, the principles of sustained cooperative endeavour, the basic demands of health and safety management, the logic of shared income and the role of specialist craftsmanship in the wider commonwealth; of the notion of apprenticeship and education; and in addition the proper design and deployment of pit props, the planned removal of spoil and other mining requirements. All modern technology and business theory starts from the silica chip. One property of flint is that if struck with metal it will fire sparks: flint was the first portable, all-purpose firelighter, and thousands of years later would become the basis of the flintlock musket.

      Silica in the form of sand became the basis for glass; it also became a bulk component of ceramic and of concrete. Out of glass, craftsmen ground the first lenses and assembled the first telescopes and microscopes, prepared the first prisms and made the first artificial rainbows from a beam of white light. The sciences of astronomy and navigation, of microbiology and the germ theory of disease, of spectroscopy and atomic theory, all begin with the exploitation of silicon dioxide. So a silica chip, first flaked from flint by an unknown hominid more than a million years ago, was the beginning of all science, and all technology; it was the beginning of the exploration of space and time, and of the tissue of life itself.

      Flint wasn’t the only agent of Palaeolithic cutting-edge technology: the earliest tool users exploited obsidian, and basalt, and bone and antler and shell, and even greenstone. But flint turned out to be the most versatile: so easily worked that tools could be made, used and abandoned; so easily found on or near the surface that hunting parties would make detours to known outcrops of chalk and flint to renew their weaponry again and again; so reliable that the tribesmen who camped in Belgium more than five thousand years ago considered it worth their while to establish a pithead, and a factory site, and to exploit the same resource for generations. And all this potential power was deposited and fashioned by the prevailing conditions deep in the oceans of the Cretaceous period, eighty or a hundred million years ago.

      It seems presumptuous to claim that human ingenuity, technology and cooperation were driven by the discovery of flint; but it might be that without a reliable supply of superior tool-making material early on in the story, without, so to speak, that extra edge, Homo sapiens might not have survived. The first anatomically modern humans are, genetically, so closely related that geneticists suspect that there might have been a population crash 70,000 years ago, leaving only small band of survivors to engender all the billions who now command the planet’s resources. In a touch-and-go world, who can be sure what tipped the balance towards survival? Our species might have disappeared in the way that Homo heidelbergensis, Homo erectus, Homo neanderthalensis all did, the last of them around 30,000 years ago. So just as chalk and flint are part of the making of Sussex, chalk and the flint that it preserves are part of the making of human history.

      This history begins, in Sussex, about 4000 BC. There were human settlers in the ancient wildwood long before that, but – I learn from Oliver Rackham’s scholarly work The History of the Countryside – around 4000 BC new people arrived, bringing with them ‘those crops, animals and weeds which constitute agriculture. They immediately set about converting Britain to an imitation of the dry, open steppes of the Near East, in which agriculture had begun.’ Perhaps the innovators were invaders, perhaps some of the existing population simply imported new strategies. The debate continues. But the wildwood they cleared was not primeval – before the ice retreated around 11,000 BC, northern Britain would have been a very large icicle, and southern England a stretch of tundra – but across what would become Sussex and other south-coast counties must have certainly been a wonderful mix of lime, oak and elm, left more or less alone to grow to enormous stature. And the people who cleared the land may never have seen or known about the Near East: it is enough that their ideas, their technology, their management of the countryside began there. By the Iron Age, dated from the sixth century BC, much of the wildwood had gone, and there were secondary woods full of coppiced hazel and other timber grown for special uses.

      The Romans occupied Sussex, but left only one famous road between London and Chichester, famous in its Saxon name of Stane Street. It is not, however, Britain’s only Stane Street: there is another one that runs between St Albans and Colchester. They built a fort at Pevensey, and called it Anderitum, СКАЧАТЬ