SPEAKER_05: Amazing, fascinating stories of inventions, ideas and innovations. Yes, this is the podcast about the things that have helped to shape our lives. Podcasts from the BBC World Service are supported by advertising.
SPEAKER_04: 50 Things That Made The Modern Economy with Tim Harford
SPEAKER_02: I found Rome a city of bricks and left it a city of marble.
SPEAKER_01: That's supposed to have been the boast of Caesar Augustus, the first Roman emperor, just over 2,000 years ago. If it was, he was exaggerating. Ancient Rome is a city of brick, no less glorious for that. Augustus was also joining a long tradition of denigrating or overlooking one of the most ancient and versatile of building materials. The great Roman architectural writer Vitruvius mentions them only in passing. Denis Diderot's great French Encyclopaedia of the Sciences, Arts and Crafts, published in 1751 and an inspiration for Adam Smith's famous description of the pin factory. Well, Diderot doesn't trouble himself to include any images of brickmaking at all. That's because a brick is such an intuitive thing. People have been teaching themselves to build simple structures out of brick for many thousands of years, and grand ones too. The Hanging Gardens of Babylon were made of brick. So was the biblical Tower of Babel.
SPEAKER_02: Come, let's make bricks and bake them thoroughly. That's Genesis 11, verse 3.
SPEAKER_02: They used brick instead of stone.
SPEAKER_01: By verse 5, the Lord is on the scene, and things aren't looking too good for the brick-loving citizens of Babel. As James Campbell and Will Price point out in their magisterial history of bricks, the humble cuboid is everywhere. The biggest man-made structure on the planet, the Ming Dynasty Great Wall of China, is largely constructed of brick. The astonishing temples of Bagan in Myanmar, the Taj Mahal in India, mighty Malbork Castle in Poland, Siena's Palazzo and Florence's Duomo, the bridges of Isfahan in Iran, Hampton Court Palace in West London – all brick. So is the best church in the world, Ayasafir in Istanbul, the best bridge, Clifton Suspension Bridge in Bristol, and the best skyscraper, the Chrysler Building in Manhattan. Brick, brick, brick. The architect Frank Lloyd Wright once boasted that he could make a brick worth its weight in gold. This all started a long time ago. Bricks seem to have been with us since the very dawn of civilization. The oldest were found in Jericho, in Jordan, by the archaeologist Kathleen Kenyon in 1952. They're something between 9,600 and 10,300 years old, and are simply loaves of mud, baked dry in the sun, then stacked up and glued together with more mud. The next big step forward was the simple brick mould, also originating from Mesopotamia, at least 7,000 years old and depicted with great clarity on a tomb painting in Thebes, Egypt. The brick mould is a wooden rectangle, with four sides but no top or bottom, into which clay and straw could be packed to make bricks faster and more precisely. These moulds can't have been easy to make. They predate the use of metal itself. But once constructed, they made mud bricks much cheaper and better. Even in a dry climate, sun-dried mud bricks do not usually last. Fired bricks are much more durable. They're stronger and waterproof. Making such bricks by heating clay and sand at a temperature of about 1,000 degrees centigrade has been possible for many thousands of years, but at a price. Accounts from the Third Dynasty of Ur, dating back just over 4,000 years, note that you could get 14,400 mud bricks for the price of a piece of silver, but only 504 fired clay bricks, an exchange rate of nearly 29 mud bricks for a single clay one. Fifteen hundred years later, by Babylonian times, kiln technologies had improved and the price of fired clay bricks had fallen to between two and five mud bricks. That's still too much for many people. Cheap and easy mud bricks are still perhaps the most popular material in the world for building houses. But as the economists Abhijit Banerjee and Esther Duflo observe, fired bricks can be an effective way for a very poor household to save. If you have a little money, buy a brick or two. Slowly, slowly, slowly, you'll have a better house. The brick is one of those old technologies like the wheel or paper that seem to be basically unimprovable. The shapes and sizes of bricks do not differ greatly wherever they are made.
SPEAKER_01: That's Edward Dobson in the 14th edition of his rudimentary treatise on the manufacture of bricks and tiles. There's a simple reason for the size. It has to fit in a human hand. As for the shape, building is much more straightforward if the width is half the length. That's why if you get your nose close up to some buildings that seem vibrantly distinctive to their culture, the minaret of Kalan Mosque in Uzbekistan, Hersemonceau Castle in England and the twin pagodas of Suzhou in China, you'll find the bricks are all much the same. It's precisely the uniformity of the brick that makes it so versatile. Many medieval buildings, such as St. Albans Cathedral in England, simply reused Roman bricks. Why not? Brick production still uses traditional methods in many parts of the world, but automation is gradually nosing its way in. Hydraulic shovels dig the clay, slow conveyor belts carry bricks through long tunnel kilns. Forklift trucks shift precision stack pallets of bricks. All this makes the brick itself cheaper. Building sites have resisted automation. The weather and the unique demands of each site require well-trained workers. The bricklayer has long been celebrated as a symbol of the honest dignity of skilled manual labour, and bricklaying tools have barely changed since the 17th century. But as in so many other professions, there are signs that the robots may be coming to bricklaying. A human bricklayer can lay 300 to 600 bricks a day. The designers of SAM, the semi-automated mason, claim it can do 3,000. What of the brick itself? Various designs of interlocking brick, much like Lego, are catching on across the developing world. The result tends to be less strong and waterproof than bricks and mortar, but they're quicker and cheaper to lay. And if you have robot bricklayers, why not give them bigger hands, so you can make bigger bricks? Hadrian X is a robot arm which lays gigantic bricks that no human bricklayer could wield. Maybe we shouldn't get too excited though. SAM, the semi-automated mason, has a predecessor, the motor mason, for which similar claims were made back in 1967. The machine spreads the mortar as evenly as a
SPEAKER_00: skilled man who has spent half a lifetime doing it. In fact, it lays bricks five to ten times faster than by the ordinary method. Perhaps the bricklayer will last a little
SPEAKER_01: longer yet. The brick certainly will.
SPEAKER_03: It was one of the defining moments of the 20th century. But it almost didn't happen. It's just crazy to try to do something as dangerous as that around the moon. I'm Kevin
SPEAKER_03: Fong and in a brand new podcast from the BBC World Service, I'll be bringing you the definitive story of the Apollo moon landings. This task had never been done, but they weren't afraid
SPEAKER_00: of it. Told by the people who were there. There were no rules. There was no field for
SPEAKER_02: what we did. Search for 13 Minutes to the Moon wherever you found this podcast to hear
SPEAKER_03: our audio countdown and be ready for the first episode. If you miss fire, you may miss the Earth. 13 Minutes to the Moon, launching on May the 13th.
