By Tim Harford Presenter, 50 Things That Made the Modern Economy
Bricks have been with us since the very dawn of civilisation. The oldest were found in Jericho, in Jordan, by the archaeologist Kathleen Kenyon in 1952.
They are somewhere between 10,300 and 9,600 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 in 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.
Accounts from the third dynasty of Ur, dating back about 4,000 years, note that you could buy 14,400 mud bricks for the price of a piece of silver; but only 504 fired clay bricks. That's an exchange rate of nearly 29 mud bricks for a single clay one.
By Babylonian times, 1,500 years later, kiln technologies had improved so much that the price of fired clay bricks had fallen to that of between two and five mud bricks.
And cheap and easy mud bricks are still perhaps the most popular material for building houses across much of the world.
But even in a dry Middle Eastern 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 1,000C, has been possible for many thousands of years - but at a price. Fired bricks were also an effective way for a very poor household to save. If you have a little money, buy a pallet of bricks. Over time you'll keep improving and expanding your home.
Heritage Buildings and Structures
- The Great Wall of China, is largely constructed of brick.
- The Hanging Gardens of Babylon were made of brick, as were:
- The astonishing temples of Bagan, in Myanmar, also known as Burma
- The Taj Mahal, in India
- Malbork Castle, in Poland
- the Palazzo in Siena
- the Duomo in Florence
- the bridges of Isfahan, in Iran
- Hampton Court Palace, in London
- Hagia Sophia, in Istanbul
- The Chrysler Building, in New York
- See more World heritage buildings
The architect Frank Lloyd Wright said he could make a humble brick worth its weight in gold.
Improving on the basic design
The brick is one of those old technologies, like the wheel or paper, that seem to be basically unimproveable.
"The shapes and sizes of bricks do not differ greatly wherever they are made," according to Dobson's Rudimentary Treatise on the Manufacture of Bricks and Tiles, first published in 1850.
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 up close to some buildings that seem vibrantly distinctive to their culture - the minaret of Kalan Mosque, in Uzbekistan, Herstmonceux Castle, in East Sussex, 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 - a lesson freshly rediscovered by every generation of parents when their children start playing with Lego.
Lego, by the way, points out that its plastic bricks don't need to be sent for recycling because they can be reused almost indefinitely. And what is true for toy bricks is also true for the real thing.
Many medieval buildings, such as St Albans Cathedral, in Hertfordshire, simply reused Roman bricks.
"Bricks manage time beautifully," writes Stewart Brand in his book How Buildings Learn. "They can last nearly forever. Their rough surface takes a handsome patina that keeps improving for centuries."
Brick production is still fired using traditional methods in many parts of the world - for example in India, handmade bricks are often fired using a Bull's trench kiln - a long trench lined with bricks that can burn almost any fuel and produce 30,000 bricks a day.
It may be fuel-hungry and polluting, but it does use local labour and materials.
Automation in production and bricklaying
Automation is common in brick production in South Africa - our country boasts some of the most technologically advanced and energy-efficient brick-making operations in the world. Hydraulic shovels dig the clay, slow conveyor belts carry bricks through long tunnel kilns, and fork-lift trucks shift precision-stacked pallets of bricks. All this makes the brick itself cheaper.
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 300-600 bricks a day. The designers of Sam, the Semi-Automated Mason, claim it can lay 3,000.
What of the brick itself? Various designs of interlocking brick, much like Lego, are catching on across the developing world. The end result tends to be less strong and waterproof than traditional bricks and mortar, but they're quicker and cheaper to lay.