Free The Ascent of Man by Jacob Bronowski Page B

wall, walls make a house, housesmake streets, and streets make a city. A city is stones and a city is people; but it is not a heap of stones, and it is not just a jostle of people. In the step from the village to the city, a new community organisation is built, based on the division of labour and on chains of command. The way to recapture that is to walk into the streets of a city that none of us has seen, in a culture thathas vanished.
    Machu Picchu is in the high Andes, eight thousand feet up in South America. It was built by the Incas at the height of their empire, round about AD 1500 or a little earlier (almost exactly when Columbus reached the West Indies) when the planning of a city was their greatest achievement. When the Spaniards conquered and plundered Peru in 1532, they somehow overlooked Machu Picchuand its sister cities. After that it was forgotten for four hundred years, until one winter’s day in 1911 Hiram Bingham, a young archaeologist from Yale University, stumbled on it. By then it had been abandoned for centuries and was picked bare as a bone. But in that skeleton of a city lies the structure of every city civilisation, in every age, everywhere in the world.

The streets of a city that none of us has seen, in a culture that has vanished.
Mortarless joints and cushioned faces of the granite blocks characterise Inca masonry .
    A city must live on a base, a hinterland, of a rich agricultural surplus; and the visible base for the Inca civilisation was the cultivation of terraces. Of course now the bare terraces grow nothing but grass, but once the potatowas cultivated here (it is a native product of Peru), and maize which was long native by then, and in the first place had come from the north. And since this was a ceremonial city of some kind, when the Inca came to visit no doubt there were grown for him tropical luxuries of this climate like the coca, which is an intoxicating herb that only the Inca aristocracy was allowed to chew, and from whichwe derive cocaine.
    At the heart of the terrace culture is a system of irrigation. This is what the pre-Inca empires and Inca empire made; it runs through these terraces, through canals and aqueducts, through the great ravines, down into the desert towards the Pacific and makes it flower. Exactly as in the Fertile Crescent it is the control of water that matters, so here in Peru the Inca civilisationwas built on the control of irrigation.
    A large system of irrigation extending over an empire requires a strong central authority. It was so in Mesopotamia. It was so in Egypt. It was so in the empire of the Incas. And that means that this city and all the cities here rested on an invisible base of communication by which authority was able to be present and audible everywhere, directing ordersfrom the centre and information towards it. Three inventions sustained the network of authority: the roads, the bridges (in a wild country like this), the messages. They came to a centre here when the Inca was here, and from him they went out of here. They are the three links by which every city is held to every other and which, we suddenly realise, are different in this city.
    Roads, bridges,messages in a great empire are always advanced inventions, because if they are cut then authority is cut off and breaks down – in modern times they are typically the first target in a revolution. We know that the Inca gave them much care. Yet on the roads there were no wheels, under the bridges there were no arches, the messages were not in writing. The culture of the Incas had not made these inventionsby the year AD 1500. That is because civilisation in America started several thousand years late, and was conquered before it had time to make all the inventions of the Old World.
    It seems very strange that an architecture that moved large building stones on rollers could miss the use of the wheel; we forget that what is radical about the wheel is the fixed axle. It seems strange to make