Ideas: A History from Fire to Freud

Pottery, as we have seen, was the first of five new substances – the ‘cultures of fire’ – which laid the basis for what would later be called civilisation. The other four were metals, glass, terra-cotta and cement. Here we shall concentrate on metals but the other pyrotechnological substances underline the continuing importance of fire in antiquity, and show how sophisticated early humans became in their understanding, and manipulation, of heat and flame.

Although archaeologists now order the ‘ages’ of man into the Stone, Copper, Bronze and Iron Ages, in that order, the first use of a metallic substance was almost certainly iron, around 300,000 years ago, when ochre found favour as decoration. Haematite in particular was popular, possibly because of its colour – red, the colour of blood and life. By Neolithic times (8000–6000 BC), there appear to have been special workshops in places like Çatal Hüyük to produce red ochre and green malachite in cakelike lumps, as a storage technique.⁵⁸ In pre-pottery Jericho three life-size plaster figures thought to portray divinities were covered in ochre. But houses too were painted red at other sites in the Middle East. As pottery developed, ochre continued as the favoured colour, though blue-green took over as the colour considered most beneficial to the dead.⁵⁹

If the colour, lustre and even the weight of metals made their impact on early humans, it was as raw rocks, or in the beds of rivers and streams that they first encountered them. From this, they would have discovered that some rocks, such as flints and cherts, became easier to work with on heating and that others, like native copper, were easier to hammer into serviceable tools. Gradually, therefore, as time passed, the advantages of metals over stone, wood and bone would have become apparent. However, when we think of metallurgy in antiquity we mainly mean one thing – smelting, the apparently magical transformation by which solid rock can be transformed into a molten metal. One can easily imagine the awesome impact this would have had on early humans.

Copper ores are found all over the fertile crescent region but invariably in hilly and mountainous regions. Archaeologists are inclined therefore to think this is where metallurgy began, rather than in river valleys. The area favoured nowadays is a region ‘whose inhabitants, in addition to possessing ore and fuel, had adopted some form of settled life and were enjoying a chalcolithic culture’.⁶⁰ This area, between the Elburz mountains and the Caspian Sea, is the front-runner for the origin of metallurgy, though the Hindu Kush and other areas have their adherents too. ‘That the discovery was fortuitously made can hardly be doubted, for it is inconceivable that men, simply by taking thought, would have realised the relationship existing between malachite – a rich-blue, friable stone – and the red, malleable substance, which we call copper.’⁶¹ Because such a link was regarded then as magical, the early copper-smiths were believed to have superhuman powers.

At one stage it was believed that ‘the camp-fire was the original smelting furnace’. No more. Quite simply, the hearths at around 4000 BC were not hot enough. Without a forced draught, ‘a camp fire, though giving enough heat to cook the food and to warm the feet . . . would not produce a temperature much higher than about 600° or 650°. Such copper ores as malachite, the easiest to deal with, are not reduced at temperatures lower than 700° to 800°C, and metallic copper does not melt below 1083°C.’ It is not only the temperature that acts against campfires. Not being enclosed, the atmosphere would not have been conducive to ‘reducing’ (separation).⁶² On the other hand, well before the discovery of smelting, much higher temperatures would have been obtained in some pottery kilns. Two-chambered kilns, with the fire down below and the pots above, had been evolved by the fifth millennium, temperatures as high as 1200°C being obtained, for example, at Susa (Iran) and Tepe Gawra (near Mosul, in Iraq).⁶³ The atmosphere in these baking chambers would have been of a strongly reducing character and modern experiments have confirmed that a spongy copper could be smelted in this way. The accident may have happened when ancient potters used malachite to colour pottery – ‘and then got the shock of their lives, when the colour delivered was very different from that anticipated’.⁶⁴