IRONWORK REPAIRS IN TIMBER-FRAMED BUILDINGS.
4.1 Historic Availability,
Characteristics and Use of Wrought Iron. 1/2.
Some scholars believe
that the quality of wrought iron and the skill of the ironsmith reached its
zenith early on and then steadily declined until its demise after the industrial
revolution demanded more materials and faster processes that led to mass production
In the book An Encylopaedia
of Ironwork, Otto Hoever gives a precise description of the rise and fall
of 'hand wrought ironwork from the middle ages to the end of the 18th century'
when he believes it fell into unrelieved decline.
However he describes
only the rich, ornamental work beloved of the church, wealthy merchants and
kings, whose expectations were of the highest. In the 12th century, abbey
and cathedral doors were being screened with superbly wrought and highly detailed
charcoal iron gates with leaf and scrollwork of outstanding delicacy.
This tradition of excellence
continued in the great European countries of Germany, France and Spain with
the peak of craftsmanship appearing in France in the C13th. In England, it
seems while the craftsmanship was not poor it was nothing but a shadow of
its European counterparts. The quality declined according to the fashions
of the times, from Gothic to Renaissance to Baroque to the final more simplistic
nature of Classicism.
In one telling phrase
he gives us an insight into the stock of iron available and its period of
'We may say that the
use of one of the three main classes of bars; flat, round and square is a
characteristic feature of a particular style. Thus Early Gothic favoured either
narrow or broad iron bands, and Late Gothic, in the north, the round bar.
In the south, above all in Italy, the Renaissance introduces the square bar
which was also preferred by Rococo smiths, particularly by the French.' (Hoever.O,
In England there certainly
was no shortage, and wrought iron and even steel for edging tools and making
weapons was being imported early on. Iron was bought by the hundredweight
(cwt) from Spain as early as 1266 and in 1275 cost 3s.1d/ cwt when brought
to Canterbury. Iron from Pont-Audemer in Normandy was being bought in Norwich
in 1285 for 15s.6d/ cwt. In 1316 they were buying Swedish Osemund, an iron
almost like steel, by the sheaf. (Salzman LF. 1952 p286).
Iron production was localised
and in particular flourished in the Weald. Although only one iron-making site
is recorded in the Domesday Book of 1086 from the 12th Century there is evidence
of a growing industry in the region, supplying markets in the south of England.
In 1496 the first documented
blast furnace was established in England in Ashdown Forest in Sussex. Within
fifty years the primitive bloomery furnaces, which had been used since the
Iron Age, had been superseded by the technology of the blast furnace and Walloon
finery already established on the continent.
Making use of water power
led to a massive expansion of the industry during the second half of the 16th
Century and resulted in over a hundred blast furnaces and associated finery
forges being established in the Weald. (Wealdon Iron Research Group, 2002).
In 1724, Neve described
the types of iron readily available in England.
(1.) English, which is
a coarse sort of Iron, hard and brittle, fit for Fire bars, and other such
(2.) Swedish, which is of all sorts the best we use in England. It is a fine
tough sort of Iron, will best endure the Hammer, and is softest to file, and
therefore most coveted by workmen to work upon.
(3.) Spanish, this would be good as Swedish Iron, were it not subject to Read
sear, (as the Workmen phrase it,) that it is to crack betwixt hot and cold.
Therefore when it falls under your Hands, you must tend it more carefully
at the Forge. But tho' it be a good, tough, soft Iron, yet, for many uses
Workmen refuse it, because 'tis so ill and unevenly wrought in the bars, that
it costs them a great deal of labour to smooth it; but it is good for all
great Works that require Welding; as the Bodies of Anvils, Sledges, large
Bell-clappers, large Pestles for Mortars, and all thick strong Bars, &c.
But 'tis particularly chosen by Anchor-smiths, because it abides the heat
better than other Iron and when 'tis well wrought, is toughest.
(4.) There is some iron that comes from Holland, (tho' in no great Quantity,)
but is made in Germany. This sort of Iron is call'd Dort-squares, (only because
it comes to us from thence, and is wrought into Bars of ¾ of an Inch
square) 'Tis a bad coarse Iron, and only fit for coarse Uses, as Window-bars,
Brewers-bars, Fire-bars, &c.
(5.) There is another sort of Iron us'd for making of Wire, which of all sorts
is the softest and toughest : But this sort is not peculiar to any Country,
but is indifferently made where any Iron is made, tho' of the worst sort;
for 'tis the first Iron that runs from the Minestone when 'tis melting, and
is only preserved for the making of Wire. (Neve, 1726 p179). Appendix
Experimentation in developing new methods of production was now widely reported.
A Weekly Essay in April 1731 from The Gentleman's Magazine (Vol 1 1731 P166)
outlines the efforts of a Mr Fallowfield in trying to use peat as a fuel and
his feud with a Mr Wood who was trying to use 'Pulveris'd Ore' burnt with
pit coal. Mr Wood, was in turn berated by a Mr Tomkyn for the poor quality
of the iron and its difficulty in working. Mr Tomkyn significantly suggests
the use of 'Pit Coal coak'd' and this is the direction mass production took.
Rising demand for iron,
fuelled in part by increased mechanisation and therefore factory machinery
was met by the 'Ironmasters'. In particular the dynasty of Abraham Darby who
developed coke fired furnaces. At first only suitable for casting iron they
were later refined to produce iron suitable for hammering into wrought iron.
This laborious process which required 12 hours of water-powered hammering
per ton was revolutionised by Henry Cort's puddle furnace of 1783-4 which
by stirring the molten iron before rolling it in a mill could produce the
same amount in only 45 minutes.
By 1775 'Iron-mad' John
Wilkinson was using Watt's steam engine (which he had manufactured) to work
the bellows of his furnaces (so that the location of the foundries was moved
from the rivers to the coalfields) and output increased. Wilkinson supplied
the components of the first iron bridge in 1779, built the first iron ship,
the first iron lavatory and the first iron coffin - in which he was buried.
'Between 1800 and 1830
the iron industry suffered gigantic convulsions in output with the change
from war to peace in 1815 and the first stirrings of railway building in the
1820s, coupled with a legacy of over-capacity from the period of rapid expansion
between 1790 and 1810. Forge technique improved during these years and wrought
iron regained its traditional position as the main end product of the industry,
establishing itself as a major export good for the first time.' (Riven. P.
In the 1830's and 1840's
iron production underwent another revolution, because of technological innovations
like the 'hot blast' iron furnace and because of the advent of a major new
customer, the locomotive railway which saw its commercial beginnings at the
Rainhill Trials of 1829.
In the 1850's considerable
scientific strides were taken in materials science and empirical values were
demonstrated for the strength of wrought iron. Using Bramah's hydraulic press,
wrought iron ties were tested to destruction in an experiment at Her Majesty's
Dockyard Woolwich (The Builder, Vol X Mar. 1852 p199). This knowledge revolutionised
the use of constructional iron as it was realised that the sectional strength
could now be accurately calculated. This of course meant that the sections
became more slender in the pursuance of economy.
Availability of puddled
wrought iron reached its peak in the first half of the C19th. In 1856 mild
steel, an alloy of iron and carbon was discovered during Henry Bessemmer's
attempts to mass produce wrought iron and this new, inexpensive and easily
machined material quickly superseded wrought iron for most uses.
However, it was not fashion or mild steel that killed off smithcraft but cast
iron. Cheaper to produce, requiring unskilled labour except for the sculptor
and founder, cast iron products could be produced en masse and all identical.