The following is based on part four of Jacob Bronowski’s BBC series on the history of science and invention, “The Ascent of Man” (1973). It is about metals, alchemy and the rise of chemistry.
Man first used fire 400,000 years ago. It kept him warm, cooked his food, kept away wild animals. But he did not learn to use it to get the metal hidden in stone till -5000 somewhere in Persia or Afghanistan: put a certain green stone in the fire and out came a red, liquid metal: copper
Copper was the plastic of its day, an almost universal material that you could shape into anything. But copper had one drawback: it was too soft. It could not keep an edge; it would wear out too quickly.
By -4000 someone made a surprising discovery: if you add tin, an even softer metal, it made a new metal that was much stronger than either one: bronze. An impure metal, an alloy, is stronger than a pure one.
By -1500 the Hittites in what is now Turkey knew how to make and work iron, which requires a much hotter fire.
By -1000 people in India knew how to make steel from iron and carbon. It was used in swords but it was so hard to make that it did not become common till the 1800s.
And then there was gold. It was not terribly useful, but in a world that is constantly changing and falling apart, it stayed the same: wind and rain could not make it rust and fire could not destroy it but only make it purer. In every age and every city it is prized above all the rest.
By 100 in China the alchemists tried to make gold out of more common materials. After hundreds of years of trial and error they failed. But along the way they learned quite a bit about the stuff that makes up the world: the chemical elements.
In the 1700s alchemy became a proper science, chemistry. That was the work of three men in the West: Priestley, Lavoisier and Dalton:
- Priestley discovered oxygen. It was because people did not know about oxygen that they thought fire was material, like air or water. Fire is not material – it is a process that takes other materials apart and puts them back together in new ways.
- Lavoisier ran Priestley’s experiments but carefully weighed everything before and after, even the air. He found that elements like mercury and oxygen always go together in certain proportions – it was not just a matter of chance. That was true for any substance that could be broken down into simpler substances.
- Dalton took Lavoisier’s numbers and asked “Why?” That is the essence of science: ask an impertinent question and you are on the way to the pertinent answer. Dalton’s question led him, in 1803, to discover that everything is made of atoms.
See also:
- Jacob Bronowski: The Grain in the Stone – part two
- Paracelsus – Bronowski talks about him too, but did not tie him well into the rest of his story. I think he just likes him and wanted to put him somewhere in the series.
- Priestley
- Lavoisier
- Dalton
- The white inventor argument
hey, i’m not sure if it is a mistake but was fire really discovered only 400 years ago?
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LOL. It is supposed to be 400,000. Thanks!
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So where are the black scientists who contributed to the march of science?
According to the white anthropologists of the world, blacks were the first humans. But when it comes to adding to the world’s total scientific knowledge, blacks are absent.
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Anthropologist tend to describe the accomplishments of a group not race. For example do we really know what the so-called race of the Hittites? Although, some people in Ethiopia are Hittites.
In so many societies the scientist and engineers of the time are not remembered as the generals and the politicians or the historians who kept the records.
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interesting this reminds me of my highschool chemistry
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what about iron smelting in africa?
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Nice! I’m studyin Chem at the month. I’ve heard of Dalton an LavoisierM but its nice to get a better history! Thanks!
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I meant to say at the moment. Lol
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