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The
Romans (c. 44- 410 AD)
In the 400
years that the Romans occupied Britain, they introduced a number
of changes to the way in which iron making was organised. There
was a massive demand for iron in Roman Britain and a large number
of ironworks were established at military bases and large towns.
Iron ore was mined at sites all across the country and the Roman
roads made it far easier to transport heavy cartloads of iron
ore to wherever it was needed. Locally there were ironworks
at Caerwent, Ely, Llantwit Major, Neath and Aberllynfi in Breconshire.
It is likely that there would have been a large amount of carefully
managed woodland around these sites to provide charcoal for
the smelting hearths. |
Above:
Roman iron implements. A billhook, a hoe and a small shears.
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After
the Romans
We know
that many things changed after the Romans left but the need
for iron remained very high. Ironworkers were considered special
craftsmen in many communities, and smiths and their skills
were highly prized. Many monks developed iron working skills
and some monasteries became centres of iron production. The
close European links of a number of monasteries meant that
any developments in skills or techniques developed in France
or Germany were quickly communicated to the iron workers of
the Welsh monasteries. By the time of the Norman Conquest
in 1066, a number of monasteries were considered major centres
of iron production. Both Neath and Margam Abbeys were granted
rights to mine iron ore and produce iron artefacts by the
1280s. All of these early ironworkers were producing iron
from small structures known as 'hearths'. The amount of iron
produced in a hearth was quite small and the hearths were
not hot enough to melt the iron, they turned it into a flexible
mass that could be hammered into shape as long as it was kept
hot.
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A
'revolution' in smelting
In the
early 1400s, a number of ironworkers in western Germany developed
a new way of making iron. Their idea was to build a bigger,
taller hearth. The effect of these new furnaces was to get
a much higher temperature which would melt the iron completely.
This new liquid form of iron could be poured into moulds of
any shape. This new 'cast' or 'pig' iron could be produced
in much greater quantities than was possible in the older
style hearths.
Right:
An early blast furnace from the 1750s.
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The news of this change spread slowly across Europe and ironworkers
everywhere started to experiment with bigger hearths or furnaces.
An important development for this new type of furnace was the
invention of bigger bellows to pump air into the bottom of the
furnace. This made the furnace fire much hotter which melted
the iron. This arrangement of tall furnace and bellows became
known as the 'blast furnace'. The first blast furnace to be
built in Britain was erected around 1490 at Buxted in Sussex.
In the years 1500-1595, many more blast furnaces were built
across the country. We know that a blast furnace was built at
Neath Abbey during these years but we do not know the exact
date. We can only confirm that it was dismantled in 1694. |
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The
blast furnace is established
By the
1600s, the blast furnace had become established as the best
way to make 'cast' or 'pig' iron. The iron produced by a blast
furnace was not a very good quality iron, it needed a lot
of working and refining by smiths and other craftsmen before
it could be really useful. This meant that the iron industry
started to grow into a much bigger industry because it needed
a range of trades and crafts. The table below shows the difference
between the early 'hearth' type of iron making and the later
'blast' furnace method.
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