As a result, bloomeries were deliberately heightened and the air blast intensified to yield cast iron as a primary product. They evolved into blast furnaces, the first archaeological evidence for which dates from the twelfth century. The first produced cast iron; the second converted it to malleable bar iron. Water power was an essential component of this new production system; it was what distinguished European metallurgy from the African.
It was not and could not be a technology of the Sahel, one of the heartlands of West African iron production. This was an environment that was both arid and labour-short, which militated against using either water or human muscle tissue as a store of energy. A strengthening of the air flow in a furnace could, however, be induced by heightening but not widening the structure.
Furnaces grew taller, just as in Europe, making the Sahel the Manhattan of African metallurgy, with natural draught furnaces that might be four metres high. Forced draught furnaces were often no more than shoulder height.
Individual smelts took an extraordinarily long time — perhaps eight times longer than forced-draught bloomeries — but labour costs were lowered. The slower smelt allowed carbon to diffuse evenly into the bloom resulting in a high-quality steel rather than the more mixed results obtained from smaller, bellows-driven furnaces. Between the eleventh and the sixteenth centuries, then, new patterns of iron production emerged in both West Africa and Europe.
In Africa, a long-established ironmaking landscape began to break up. Small-scale production for local consumption had been pervasive and continued to be so, but areas that were blessed with unusually rich ores started to develop smelting capacity above and beyond local needs.
This was still smelting on a batch basis but specialization enabled districts such as Bassar to produce surpluses for inter-regional trade from the sixteenth century onwards. It was a striking piece of synchroneity. When a transatlantic slave trade took root in the sixteenth century European traders had every incentive to include iron in the cargoes they shipped south because north European bars, produced at blast furnaces and water-powered forges with throughput speeds that African smelters were quite unable to match, could be hugely profitable.
The returns on iron ranged from to per cent, making it the most lucrative commodity the Danes dealt in. There were other goods, such as tobacco pipes, which could bring in profits at over per cent, but they were only sold in very small quantities.
Textiles, which made up the bulk of what was taken to Africa, realized much lower returns, ranging from the 70 per cent to be had for Indian fabrics such as romals and niccanees to a meagre 14 per cent on long ells, a coarse English woollen. Both had to rely on imported iron. The Dutch were fortunate in that the Rhine and Meuse rivers gave them ready access to iron-producing districts in Wallonia, the Ardennes, and the Rhineland.
In the seventeenth century, however, English ironmasters encountered fuel shortages that put a ceiling on production. The consumption of iron in Britain could only continue to grow if domestic supplies were augmented by imports. Should Swedish supplies be insufficient, they could be supplemented by purchases made on the Dutch market.
Voyage iron that did not meet the exacting requirements of African buyers would find no sale. The correct length of voyage iron or Guinea iron is about 11 feet, and of such weight that 18, 19 or 20 bars of it make 5 cwt or 76 to 80 bars in a cask of 20 cwt. It must be smooth and well forged. There is much discussion when there are cracks along the edge of the bars … The buyers in England take great offence at this. Traders who arrived with iron of the wrong dimensions would be at a competitive disadvantage.
The difficulty for European slavers was that the desired measurements shifted over time and timely notice of such shifts was required if they were to furnish what was needed. Its manufacture was therefore a specialized business. The supply of voyage iron to English traders was confined to Sweden and the territories drained by the Meuse and the Rhine because ironmasters there were able to respond smartly to market signals in ways that their Russian counterparts could not.
To be more accurate, Swedish ironmasters were able to respond to information brokered by iron merchants who catered for the slave trade, men such as Graffin Prankard d. Every winter Prankard would quiz returning slave captains about the state of the market along the African coast.
Once he was satisfied about the dimensions currently favoured for voyage iron and had formed some idea of the volume required for the coming year, he issued instructions to his agent in Stockholm. This was in February. If everything went well, voyage iron from Sweden could be in Bristol and ready for dispatch between June and October, the peak months for ships clearing for African destinations.
This was not an arrangement that worked without hitch. The same arrangement could not be made to work with Russia. The time that would elapse between iron being forged on the Ural frontier of the Russian Empire and its arrival on British markets was too great. The bars would therefore have to be re-sized at an English rolling mill. Not only did this in itself bear a cost, but the iron thereby became a British manufactured article in the eyes of revenue officials and lost the customs drawback available to simple re-exports.
Voyage iron had to be of the correct size and weight because it acted as specie. The Scottish explorer Mungo Park reflected on this upon his arrival in Senegambia in the s. Africans, he realized, appreciated iron for its use value but it was also used to embody exchange value. In their early intercourse with Europeans, the article that attracted most notice was iron. Its utility, in forming the instruments of war and husbandry, made it preferable to all others; and iron soon became the measure by which the value of all other commodities was ascertained.
Twenty leaves of tobacco, for instance, were considered as a bar of tobacco; and a gallon of spirits or rather half spirits and half water , as a bar of rum; a bar of one commodity being equal in value to a bar of another commodity.
As such, the bar had a dual nature. On the one hand, it was an index of abstract value, as was made plain in the invoices of British slave ships which priced their cargo both in sterling and bars. It was in steady demand as a store of wealth.
It was also in demand as a material from which agricultural implements or weapons could be fashioned. European travellers commented on the skill with which African blacksmiths did so. Our knowledge of African consumption is imperfect but some broad patterns are clearly discernible. The interior was well supplied with iron; the forested coast was not. Voyage iron was taken up avidly in coastal communities, such as those of the Balanta, which needed weaponry to resist predatory neighbours in an age of intensifying slave-raiding.
Indeed, to pay for iron, the Balanta resorted to slaving themselves. In adapting to this new habitat, they turned to the cultivation of rice.
Iron was essential here too. Traditional tools made of fire-hardened wood could not cope with tangled mangrove roots; metal-tipped implements could. The effect of voyage iron on Guinea-Bissau was therefore twofold. It ratcheted up the seizure of captives while generating food surpluses that European slavers could use to sustain those captives during their transatlantic ordeal. Rice was an ancient African grain, but voyage iron was also of profound importance for the New World cultigens that were introduced to coastal West Africa in the early modern era.
The plant species that the Colombian Exchange brought to the Guinean forests — cassava, beans and maize — were transformative. They supplied bulk carbohydrates to a region that had previously known shortage, allowing for a sharp rise in the coastal population, a more complex social division of labour, the emergence of royal bureaucracies, and the formation of standing armies.
Maize was of particular significance. Yielding two crops a year and requiring relatively little labour, it spread rapidly through the forest zone. But the success of maize depended upon piercing the forest canopy, for it is a species that demands abundant sunlight if it is to thrive.
Because of the very long fallow periods favoured by forest agriculturists trees were able to re-establish themselves. As a result, programmes of clearance had to be re-enacted, again and again.
There was a shift in the centre of social gravity, away from the city states and empires of the interior, and away from the trans-Saharan caravan trade that had for centuries linked them to the Mediterranean world.
The Atlantic now exerted a gravitational pull it had previously lacked. The extent of voyage iron imports is difficult to assess, but there is evidence enough to suggest that they represented a major addition to the stock of iron in West Africa. That was equivalent to between and tons. The answer from Upper Guinea Senegambia and Sierra Leone was that 13, bars or about tons should always be in stock.
By permission of the publishers. All rights reserved. Stocks are not the same as sales, but they are indicative. And to the volume warehoused by the English must be added the stocks held by the Dutch at their forts, and the contributions made by other nations, not least the French, whose slave trade was on the verge of explosive growth.
Actual sales could be erratic, of course, as erratic as the slave trade itself. In , his best year in the trade, Graffin Prankard of Bristol sold tons of voyage iron to the slave merchants of his city. Not only was the trade in captives expanding but the areas of greatest growth, such as the Bight of Biafra, had a marked appetite for European metals.
That, at least, is the message of what little hard data survives. Some tons of voyage iron was shipped from Stockholm in , mostly for English ports. This was a formidable quantity, one that eclipsed the productive capacity of any specialist smelting zone in sub-Saharan Africa. African smelters were unquestionably skilled and numerous but they were restricted to small batch production and could not match the productivity of northern European ironmakers.
Indeed, the indications are that African demand for voyage iron was on an upward path. Tellingly, the size of the standard bar was shrinking over the course of the eighteenth century. Bars made for the African market in the seventeenth century were between twenty-eight and thirty English pounds apiece. By the time of the American Revolution the standard weight had slipped below twenty pounds; by the first decade of the nineteenth century voyage iron was consistently below fifteen pounds per bar see Figure 1.
This phenomenon is best explained by a growing appetite for iron in West Africa, which pushed prices higher. The terms of trade were turning in favour of Europe. This makes the case of iron highly unusual. The sharply increased demand for African slaves, the rising competition among Europeans, and the growing centralization of African ties to the Atlantic trade all served to strengthen African trading positions.
As the terms of trade shifted steadily in their favor, African traders received goods for each slave worth three or four times as much in as a century earlier. Figure 1 shows the weight of individual iron bars traded to Africa.
The data are mostly from the invoices of English vessels, which conventionally recorded the number of bars in a consignment and their overall weight. We have data points between and That for is an outlier; it is not until that our data begin in earnest.
Thereafter the data are reasonably continuous, albeit with gaps in the s, between the mid s and mid s, the late s, and the mid s. The downward trend over the course of the eighteenth century is clear, despite some anomalously high observations in the mid eighteenth century. The bars carried on the Little Britain in the same year are described as voyage iron but they are so off-trend — 48 lbs at a time when the standard bar was about 20lbs — that there is no ready explanation.
Iron carried to the Gold Coast by the Danes in the s and s divides into two quite distinct types. Some parcels conform closely to the overall trend; others are markedly heavier. It may be that the heavier bars were intended for use by smiths at the Danish fort of Christianborg. We are now in a position to address some basic questions about the overarching ferrous relationship between Africa and Europe in the era of Atlantic slavery. Africa was not, it must be said, a major market for north European exporters.
European iron made its way to Africa in other ways, of course. It was embodied in many of the manufactured goods that played a key role in the Atlantic slave trade, most notoriously in musket barrels. Nevertheless, we can be tolerably confident that Africa absorbed only a small proportion of European iron output. But what of the importance of voyage iron for African consumers? This is a far more complex issue.
It was a dependable, indeed indispensable, staple but, like many other workaday commodities, it is easily overlooked. Indigenous African irons have proved far more beguiling to scholars because they raise such profound questions about technological creativity and cultural transmission. The issue of whether ferrous smelting diffused into sub-Saharan Africa or was an autochthonous development carries — for some at least — a political charge.
The tenacity of sub-Saharan smelting traditions, which endured into the twentieth century, bears political freight too. It demonstrates the resilience of indigenous knowledge in the face of colonial science. The evidence provided above suggests that European bar iron played a vital role. The coastal forests of West Africa were deeply affected, as the experience of Guinea-Bissau and the Gold Coast suggests. The competition set the stage for the scramble for territories in Africa.
With their most profitable trade seemingly now gone, Europeans turned to the natural resources of West Africa again. These resources were now required in greater quantities to feed the expanding European manufacturing industries. In order to maintain their hold on these colonies to the exclusion of other Europeans, the dominant powers had to exercise both economic and political control.
Economic control included the creation of infrastructure most of them ancillary to exploitation and established political authority. By the end of the 19th century, most of the world's valuable colonies were in Africa. By , the political map of Africa was complete and little or few changes took place prior to the march to Independence. The land explorers were followed by Christian Missionaries, who preached the Bible, introduced Western education, condemned aspects of traditional African practice, and converted many Africans into Christianity.
At the of World War I, the victorious allies took over German territories. France ruled her share as separate countries. The final breakdown of African Territories among European Powers was as follows :. Dahomey now Benin. The colonial powers adopted different approaches to rule their African territories.
Some European powers such as the French sought to convert Africans in their colonies into French citizens. With others such as the British, Africans were made to rule over themselves while they appointed some local people as state officials who worked for the British Crown.
The various European administrative policies are explained below. The British adopted two approaches in their territories in Africa. In areas such as South Africa and Northern Rhodesia Zimbabwe where some whites settled permanently, the British treated such territories as extensions of Britain.
For example, in the highland regions of east Africa, South Africa etc, the British assumed that their outposts would develop along the lines of Australia, New Zealand, and Canada. The complication was that, unlike Australia, New Zealand, and Canada where native population was tiny, Africa was populous and the natives resisted European rule. British policy in such territories aimed at safeguarding the interest of native and non-white immigrants with a system based on the political and economic dominance of the white minorities.
The British sought to entrench certain clauses in the constitutions of these countries to safeguard the rights of the natives as they moved towards self-rule. However, they did not question the rights of the white minorities to rule the majority indigenous population.
These clauses were to no avail as the white minorities took control of the territories as happened in the case of South Africa, Zimbabwe, and other areas. In other parts of Africa, especially in West Africa, the British approach was different.
They devised what they called Indirect Rule to administer their colonies. The colonial possessions were territories held in trust and consequently it was Britain's obligation to develop the resources of the colonies not for the exclusive benefit of Britain but for humankind generally. The British did not interfere with existing native institutions but used them to implement policies that benefited them. Where no such viable local institutions existed, British efforts to create them often caused confusion and chaos.
By relying on existing traditional institutions and the natives themselves, the British reduced confrontation and protests from local people. It also gave some autonomy to local citizens and somehow prepared their leaders for early independence as it happened in Ghana. Unlike the British, French rule in Africa was well defined and more pragmatic in its aims and methods. It was based on two main principles: Direct Rule and Assimilation. The French believed themselves to be the heirs of the Roman traditions and saw their mission as that of a Superior Race with a duty to extend benefits of their advanced civilization to the Backward Inhabitants Africans in their colonies and reward them with French Citizenship when they showed sufficient evidence of having embraced this civilization.
Catholic countries such as Portugal were, in theory at least, forbidden by papal injunction from selling items with potential military uses to non-Christians, although it is unclear how closely this order was followed in practice.
In exchange for their wares, Europeans returned with textiles, carvings , spices, ivory , gum, and African slaves. Contrary to popular views about precolonial Africa, local manufacturers were at this time creating items of comparable, if not superior, quality to those of preindustrial Europe.
Due to advances in native forge technology , smiths in some regions of sub-Saharan Africa were producing steels of a better grade than those of their counterparts in Europe, and the highly developed West African textile workshops had produced fine cloths for export long before the arrival of European traders. It may therefore seem surprising that European importers found many customers for their goods among local populations in West Africa.
Nonetheless, the novelty and comparative rarity of European imports together constituted a significant advantage over local products, and powerful rulers readily adopted them for use as courtly regalia. Round, white shells are valued symbols of spirituality and leadership in many Central African cultures, and European merchants clearly created this ceramic form to meet the particular demands and interests of their trading partners.
Local leaders who prospered from the international trade also commissioned other prestige objects, such as sumptuous wood and ivory carvings , from local artisans. Bortolot, Alexander Ives. Bassani, Ezio, and William B. Africa and the Renaissance: Art in Ivory. Exhibition catalogue. New York: Center for African Art,
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