Fire and Metals — Primal Discoveries, by Design
Editor’s note: We are pleased to present a series adapted from biologist Michael Denton’s book, Fire-Maker: How Humans Were Designed to Harness Fire and Transform Our Planet, from Discovery Institute Press. Find the whole series here. Dr. Denton’s forthcoming book, The Miracle of the Cell, will be published in September.
The primal discovery of fire opened a long path towards modern technology. The ability to tame fire led to the invention of the art of cooking and to the discovery that fire hardens lumps of clay into hard stone or pottery, which can be molded into containers for storing food. This initiated the development of mankind’s first industry — ceramics, which was well established in many parts of the world before 10000 BC.1
The mastery of fire also led to the discovery and manufacture of charcoal, produced by burning or “cooking wood” in an oxygen depleted environment (a technique used by cave artists as early as 30000 BC2), and to the discovery that burning charcoal generates far greater heat that an ordinary wood fire.3 This in turn led to the use of charcoal to generate high temperatures inside kilns for the manufacture of baked and glazed pottery, using bellows to give a forced draft to raise the temperature inside the kiln.4
A Particularly Hot Campfire
Perhaps it was the chance heating of a metal ore in a particularly hot campfire and the subsequent discovery of globules of metal the next morning upon “raking through the ashes”5 which first led to the discovery of metallurgy. Or perhaps, as other authors have argued, the discovery that metals could be extracted from their ores was discovered in a pottery kiln, where the charcoal-fueled fire would have generated temperatures hot enough to smelt metallic ores.6 As Arthur Wilson comments in his Living Rock, “Adapting… [the process of glazing pottery in a kiln using charcoal as a fuel], copper ores could thus have been reduced to obtain metal.”7
Although no one knows exactly what sequence of events led to the beginnings of metallurgy,8 there is little doubt that it was another momentous discovery, second only to the discovery and mastery of fire itself. As Arthur Wilson comments: “In whatever manner the secret of metallurgy was unraveled—and we shall never know precisely—it was a momentous step along the road to civilization… man, though still stumbling, entered the Age of Metals and opened up undreamed of possibilities for his future.”9
Copper was one of the first of the metals to be widely used and there is evidence that mankind mastered the smelting of copper as early as 7,000 years ago.10 The subsequent extraction of copper from copper-bearing ores and its mixture with tin to make bronze was independently discovered by cultures in both the old and new worlds11 and ushered in the Bronze Age in the Ancient Near East about 3500 BC.12
Tomorrow, “For Mankind, Copper to Iron Was a Landmark Advance.”
- “Pottery,” Wikipedia, May 16, 2016, accessed on May 17, 2016, https://en.wikipedia.org/wiki/Pottery; See Xiaohong Wu, Chi Zhang, Paul Goldberg, David Cohen, Yan Pan, Trina Arpin, Ofer Bar-Yosef, “Early Pottery at 20,000 Years Ago in Xianrendong Cave, China,” Science 336, no. 6089 (2012): 1696–1700. doi:10.1126/science.1218643. PMID 22745428; PIMD23575637.
- Peter Harris, “On Charcoal,” Interdisciplinary Science Reviews 24, no. 4 (April 1999): 301–306. doi:10.1179/030801899678966; version of article on web: http://www.personal.rdg.ac.uk/~scsharip/Charcoal.htm.
- Ibid.; Lee Horne, “Fuel For The Metal Worker,” Expedition Magazine 25, no. 1 (October 1982), Penn Museum, accessed May 17, 2016, http://www.penn.museum/sites/expedition/?p=5281. Horne comments: “As an accidental by-product of combustion, wood charcoal has certainly been known for as long as fire itself. Very probably its peculiar properties, such as smokelessness and high burning temperature, were appreciated early on and even taken advantage of from time to time. At some unknown point in the past, however, charcoal began to be produced for its own sake, and not simply as a by-product in the course of building fires for other purposes. Eventually it became a commercial product, and charcoal production became another way to earn a living. The wood from which charcoal is made became an important industrial resource, just as essential to the production of metal as the ore itself.”
- Arthur Wilson, The Living Rock: The Story of Metals since Earliest Times and Their Impact on Developing Civilization (Cambridge, England: Woodhead Pub., 1994), 10-11.
- Ibid., 10.
- Ibid; “Smelting,” Wikipedia, May 6, 2016, accessed May 17, 2016, https://en.wikipedia.org/wiki/Smelting: “How the discovery [of smelting copper] came about is a matter of much debate. Campfires are about 200° C short of the temperature needed… so it has been conjectured that the first smelting of copper may have been achieved in pottery kilns.”
- Wilson, 11.
- Ibid.,10-11; “Smelting,” Wikipedia.
- Wilson, 11.
- “Chalcolithic,” Wikipedia, May 15, 2016, accessed May 17, 2016, https://en.wikipedia.org/wiki/Chalcolithic: “The archaeological site of Belovode on the Rudnik mountain in Serbia contains the world’s oldest securely dated evidence of copper smelting at high temperature, from 5,000 BCE.”
- “Bronze Age,” Wikipedia, May 16, 2016, accessed May 17, 2016, https://en.wikipedia.org/wiki/Bronze_Age: As the article comments: “The Moche civilization of South America independently discovered and developed bronze smelting. Bronze technology was developed further by the Incas and used widely both for utilitarian objects and sculpture. A later appearance of limited bronze smelting in West Mexico (see Metallurgy in pre-Columbian Mesoamerica) suggests either contact of that region with Andean cultures or separate discovery of the technology. The Calchaquí people of Northwest Argentina [also] had Bronze technology.”