Fire
By Rochelle Forrester
Ó All Rights Reserved
Publication Date 2006
There is some doubt as to when hominids first began to use fire. The earliest known use of fire was by Homo erectus about 300,000 to 400,000 years ago. Human kind almost certainly learnt the use of fire due to the observation of natural fires caused by lighting strikes, volcanic eruptions or some other natural cause. Fire could be obtained from natural fires and kept alive by adding additional fuel and could be put to use by our ancestors. The ability to actually make fire was only learnt much later after fire had been used for a considerable time.
The main difficulty with the making of fire is the problem of ignition. This is why human kind learnt to use fire long before it learnt to make fire. Around 12,000 BC humans were able to make fire by rubbing certain stones such as iron pyrites against flint which caused sparks which could set alight dry leaves or grass. Around 8,000 BC fire could be made by rapidly turning a stick in a hole in another piece of wood. Later a bow was used to spin the stick making the whole process somewhat easier. Such stone age methods of producing fire are difficult and unreliable and it was not until the 19th century after the discovery of phosphorus, a highly inflammable substance, that fire could be easily produced.
Once humans had learnt to control fire it soon developed a wide range of uses. Fire was used to keep people warm especially at night and in colder climates. It was used to provide light allowing humans to work after dark and to explore the depths of caves. Fire was used to keep predators away as other animals are afraid of fire. Fire was also used in hunting to drive prey over cliffs or into swamps where they could be more easily killed. It was also used to destroy old vegetation to produce re-growth that provides good grazing for the animals humans hunt. Fire was also used for cooking and the sharpening of spears. After the development of agriculture, fire was to play an essential role in the development of pottery, metallurgy and glass.
The effect of the uses of fire was certainly to allow a substantial increase in human population due to a greater food supply from better hunting and cooking and a reduced mortality from wild animal attacks. Hominids were able to occupy territories with colder climates such as Europe and Northern China. Human activities could continue at night and access to dark caves became possible. It is likely the use of fire turned human beings into the leading predator on the planet.
Fire is the result of a chemical reaction between oxygen and an organic (e.g. carbon based) compound. Oxygen is contained in the earth’s atmosphere and organic material which includes all plant life is widespread so fire can be used nearly everywhere on the planet. The chemical reaction which causes fire produces both heat and light which are valuable products for human beings.
The use of fire initially involved the use of natural fire a much simpler process than the difficult task of actually working out how to make fire, a development which occurred much later than the first use of fire. The order of discovery of the use of natural fire before the discovery of how to make fire, was inevitable. This was because it was easy to use natural fire, which was supplied by nature, and much more difficult to make fire given the difficulty of ignition.
Fire has had a major effect on human history. If it were possible to easily make fire, then history would have been different as the making of fire would have occurred much earlier in history. Equally, history would be different if it was impossible to make fire and we always had to rely on natural fire. However the most significant change in history would be if fire could not happen at all. If oxygen simply did not react with organic matter to produce fire, or the reaction only took place at a very high temperature so that fire could not be made or even occur naturally then history would be radically different. The development of pottery, metallurgy and glass would have occurred much later in history or possibly not at all. If fire had different properties, for example if it burnt at much higher temperatures, say 2,000oC, then the entire history of metallurgy would have been much different. Special kilns and ovens needed to produce high temperatures for metallurgy would not have been required. Human beings would have been able to smelt and melt iron at a much earlier stage in history so there would have been no bronze age and hunter-gatherers could have used iron tools and weapons.