75 Stone street
Introduction
People have been building with rocks for thousands of years. The pyramids of ancient Egypt were mostly built from limestone blocks that were carved from local quarries nearly 4,500 years ago. The insides of the pyramids were lined with granite. This had to be brought from a quarry 800 kilometres away and was transported down the River Nile on rafts.
Stonehenge, the ancient monument of huge stones standing on Salisbury Plain in Wiltshire, has captured imaginations for centuries. Stonehenge means ‘hanging stones’. Investigations over the last ten years have revealed that Stonehenge was built in several stages from 3000-1500 BC.
The Romans used stone to build Hadrian’s Wall to keep out the barbarian tribes of the present day Scottish Highlands. When it was built in the second century AD, the wall was 80 miles long, 6 metres high and 3 metres wide. It was one of the Roman Empire’s greatest feats of engineering.
Local rock was used by British farmers in the eighteenth and nineteenth centuries to make stone walls to enclose their lands. It’s often possible to tell where the types of rock change between different areas of the country by looking at the rocks used to make these walls.
These days it’s not just Fred Flintstone or Barney Rubble who live in houses made of aggregates (crushed rock or stone). Whether you live in a house built last year or 100 years ago, it will have been built of, or from, aggregates such as sand and gravel.
To make the aggregate, rocks are dynamited from the land, then crushed at the quarry. In some places gravel – small, rounded stones that have been weathered and eroded by water – can be found. This makes an excellent aggregate.
In older houses, stone was used for making the walls and slate for making the roof. But modern houses are made almost entirely out of manufactured materials - that’s because building materials that have already been shaped are much easier to build with than rough, natural stone.
But never forget one VERY important fact; all these manufactured materials (concrete, plaster, bricks, etc) are themselves made from rock.