Building materials of the ancient world

Our ancestors were much smarter than people realize, living in elaborate castles with polished plaster interior walls, and wearing fine linen and leather clothing. They knew how to smelt metals and make everything from weapons to supports for bridges, but how exactly did they do all this and how can people who are often seen as being primitive manage to make these things?

 

(A wattle and daub wall, one of the most common forms of wall building from the bronze age to gunpowder era)

 

How were medieval castles built?

There were two types of castles in European history, which were the motte and bailey castle and the classic stone castle. Motte and Bailey style castles involved a lot of digging and construction of something called a palisade wall, which consists of verticle logs with sharp points standing up-right in a trench. The logs touch each other and are supported from behind with additional beams and sometimes a walkway for defense. Even though they are straightforward, they can be built quickly and are extremely difficult to climb from the outside, as the smooth barkless, and verticle logs offer nothing to use for grip.

 

(The top of a palisade wall from the inside, the bottom of the logs are dug into a deep trench)

 

A couple of hundred years after the first motte and bailey castle appeared, stone keeps and outer walls began to take their place. They could be built much higher and couldn’t be burned down, but weren’t possible without something called mortar, an early cement-like material that was used in construction for hundreds of years, if you’d like to know how to make it then check out this medieval mortar-making guide. If you visit a medieval castle in Europe then this is the type of mortar found between the stones.

 

How were Celtic roundhouses built?

People refer to them as Celtic roundhouses but the roundhouse was a common design seen across most of the northern European and Asian hemispheres. The circular wall frame is made by digging posts into the ground and using cut logs to connect them all. The roof is a simple design and can be seen below, but the most unknown part of the construction is the wattle and daub, a material that can be seen across the entire ancient world. It was made by mixing equal parts of soil, clay, animal manure, and some kind of binder like straw or hay. It was then mashed into a thick paste and smeared on either side of the wattle wall, a lattice fencing that sits in between the beams. The layer of daub will be several inches thick and when it dries, will be windproof and does a surprisingly good job at keeping in the heat.

 

(Thatch is attached to each of the cross-sticks to create an overlapping effect)

 

An interesting point about the classic roundhouse is that the central fire did more than keep the place warm. With no chimney or open area on the roof, the smoke had to escape through the thatch which helped to preserve it and stop it from rotting. Another bonus of this is that flies and insects hate smoke, which meant the roof would often be free of spiders and other things you might not want to sleep next to.

 

(An example of a wattle and daub wall being built)

 

How did they carve stone for building?

The method that ancient people all over the world used to cut stone is still used to this day. A series of holes are drilled or carved out with chisels along the line where the stone needs to be split, then smaller chisels are placed into the holes and struck with a hammer in a line. Eventually, a crack will form along the chisel line and the stone will split, with the process repeating on a smaller scale for smaller bricks. The other way they would carve stone was to chip off little pieces from a block until it was the right shape, which they would only often do for one side of a stone. If you ever have the chance to see inside a partially collapsed castle wall, you will notice the sides of the stone on the inside are random shapes and the gaps are filled in with either smaller stones or mortar, only the flat, carved side will be pointing outwards and visible.

 

(The Inca fortress of Sacsayhuamán, with stones cut so perfectly that no one knows how they did it)

 

The most mysterious and challenging ancient stones are found within the buildings of the Inca empire who made a fort called Sacsayhuaman that included huge stones weighing over 100 tons. The interesting thing about their stone-cutting methods is that the stones sit so perfectly together without any kind of mortar, that you can’t even slide a piece of paper in between the gaps. How they cut stone so perfectly and with such accuracy is one of the great mysteries of the ancient world.

 

How did they create metal tools and weapons?

The first metal used was copper, with the copper age beginning in Britain around 3500 BCE and ending about 500 years later when people discovered how to make bronze. Copper has a melting temperature of 1,085 °C and can be melted by putting it on a stone in the middle of a large fire, but it didn’t take long for people to make smelters for this purpose. When you mix copper with tin, which has a melting point of 231.9 °C, you get bronze which is stronger than both metals on their own. Clay and stone smelters would have been filled with coal or charcoal and the ground-up metal ores would run out the bottom into a mold.

bellows

(A set of bellows, a simple invention that could provide the necessary amount of air into the smelter to increase the temperature)

 

It wasn’t until around 800 BCE that someone discovered how to melt iron, a previously un-meltable ore that could be found everywhere. Iron has a melting point of 1,538 °C which is far too hot for a large fire or bronze smelter and requires the constant blasting of air from bellows to produce the necessary heat. One advantage our ancestors had when trying to find ore is that no one had previously tried to mine it, so huge deposits could be found on the surface.