Reasons for Designation
Wortley Top Forge is a complex of great importance and demonstrates
continuity in the production of iron from at least the early 18th century. The
adaptation of a finery forge to secondary wrought iron working is rare and its
survival unique. The buildings, machinery, and water management system will
add greatly to our understanding of the iron industry in this part of the
country. The physical remains, combined with the documentary evidence of
leases and accounts, provides evidence of the technological developments in
the industry and how these were accommodated and administered within the
works. The survival of the workshops, the former office and cottages enhances
the importance of the complex by providing evidence for the domestic
arrangement of those who worked within it.
Details
The monument includes the standing and below ground remains of Wortley Top
Forge and its associated water management system. The monument is situated in
a bend of the River Don approximately 14.4km north west of Sheffield. It
is the only survivor of a group of water-powered works which utilised the
natural water supply of the upper reaches of the River Don. Originally the
Wortley ironworks comprised the Low Forge, which was situated lower down
the river and is now derelict, and the Top Forge which survives today.
The Green Moor quarries, a few hundred metres to the west, may have provided
building stone for the complex. Charcoal for fuel was available from the
surrounding woodland and pig iron was bought in from furnaces at Barnby and
Bank, a few kilometres to the north. The forge is now a monument preserved by
voluntary groups.
Iron-making in this area is suggested as early as 1379 when it is known that
there were four `smythes' and a `master' in Wortley. Although records dating
to 1621 mention a bloomery in Wortley, the first clear reference to the forge
as a finery comes in a lease of 1658. A finery forge was a specialised forge
in which pig iron was re-melted in oxidising conditions to produce wrought
iron. At this time, and until the mid-18th century, Wortley Forge was
administered by the Spencer Partnership which operated a group of eight blast
furnaces and 11 iron forges in South Yorkshire. Wortley was particularly
active in the first quarter of the 18th century, a period when the buildings
underwent extensive alterations. The surviving buildings are mainly early 17th
century with later alterations. The forge building retains a date stone of
1713 and includes the initials `MW', a reference to the manager at the time,
Matthew Wilson. The forge may, however, also retain some 17th century fabric.
In 1746 the lease was taken over by the Cockshutt family, with John Cockshutt
the younger taking on the lease in 1793. The Cockshutt family were
responsible for introducing a variety of new machines and processes to Wortley
Top. They were aware of new processes which allowed wrought iron to be
produced on a large and economical scale for the first time. Their
introduction of a new rolling mill, mentioned in a lease of 1793, was the
first with grooves to be introduced in Yorkshire. It is also thought that one
of the Cockshutts made steel by the cementation process at Wortley in the late
18th century.
Less is known of the history of the forge in the early years of the 19th
century, although it is known that the production of railway axles began about
1850. Wortley became renowned for the quality of its products during this
period. This reputation was particularly enhanced by Thomas Andrews Junior who
was a noted a metallurgist in the last years of the 19th century. This was the
peak of the forge's history. When Thomas Andrews died in 1907 the works were
taken over by the Wortley Iron Company under J and B Birdsell. Top Forge was
finally closed in 1908 but the lower forge remained in operation until 1929.
In its present form, Wortley Top Forge represents continuity in iron
production from at least the early 18th century to the beginning of the 20th
century, and has experienced several different processes of manufacture. The
earliest, the bloomery, or direct reduction process, produced wrought iron for
the smith direct from the ore. However, none of the surviving structures
relate to this period, although bloomery cinder can be found at Top Forge.
The introduction of the `Walloon' process, in which pig iron was converted to
wrought iron, determined the principal layout of the forge from which the
present arrangements have derived. The extensive alterations of 1713 would
accommodate finery hearths in which pigs of cast iron would be remelted. The
iron from the finery would then be forged by water powered hammers, with a
chafery hearth used to reheat the bloom during the forging process. The axle
making activities after 1850 required bundles of wrought iron bars (typically
16) called faggots to be heated in furnaces for welding under the tilt
hammers. The furnaces were placed to the west of the forge with draught
provided by three chimneys, now gone.
The monument survives both as standing and below ground remains. The main
forge building, which is Listed Grade I, is mainly early 18th century in date
but retains evidence of different phases of construction. Structural
alterations were probably carried out as technological changes dictated but
the surviving functional layout is mainly mid-19th century in date. The stone
building is rectangular in plan with a continuous outshut (an extension
running along the length of the building under a lean-to roof), and housing
for the blower wheel, along the west side of the building. Along the length of
the west wall are four segmental arches with brick voussoirs. Adjacent to the
outshut is a small rectangular room which was used as a foreman's office.
Adjacent, but bonded to the eastern wall of the forge building, are two pits
which house water wheels; Wheel 1 at the northern end of the wall and Wheel 2
in the centre. The east wall has a large rounded, arched opening for each
wheel with a single, square headed smaller doorway to the south of each. Above
the level of the arched wheel openings, and spaced along the length of the
wall, are three square windows. At the southern end of the east wall, and
slightly set back, is a two bay arcade with brick voussoirs supported on two
round cast iron columns. The date stone is set in the northern pier of this
opening. Originally the building was covered by a stone roof but during
alterations around 1880, when part of the roof was raised to allow greater
ventilation over the furnaces, only the best stone was kept and slate was used
to make up the difference. Now the upper roof is of welsh slate and the lower
roof of stone.
A considerable amount of machinery remains in situ in the forge building.
Wheel 1, a one piece iron casting with modern wooden paddles, is 3.6m in
diameter, breast shot and with a cast iron axle. This probably replaced an
earlier wooden wheel. Wheel 2, which is also breast shot, was installed in the
mid-19th century. It is cast iron, 4.1m in diameter, with separate felloes and
later wooden paddles. The blower wheel is again cast iron, with wooden
buckets, and is fed by a cast iron pentrough (dated 1850), which is situated
above the wheel. A shuttlemouth beneath the pentrough directed the water on to
the top of the wheel which then drove the bellows to provide the blast for the
forge furnaces. Although the blower itself is now missing, its position is
evident from the stone bed plates which lie immediately to the east of the
blower wheel.
Wheels 1 and 2 were used to drive the two belly helve hammers (hammers which
are lifted by a cam operating upon the underside of the hammer beam, or
helve). The hammer driven by Wheel 1, is provided with a spring beam, a
naturally curved tree trunk which acts as a spring to give a heavier blow.
This hammer, although altered by the addition of cast iron parts, still has a
massive timber framework of uprights and beams, is of 18th century type, and
in essential layout dates from the finery period of the forge. The second
hammer is a later free fall hammer and is all iron in a cast iron frame. The
axle making activities after 1850 required welding under the hammers and both
of the hammers are fitted with heads and anvils of a suitable shape but hammer
2 is of a size and type more appropriate for heavy work. Four cranes were in
use at the forge and these survive. Two cranes close to the hammers were used
to help the furnacemen place faggots into the furnace and then to withdraw
them after heating. The cranes also supported the white hot faggots as they
were being manipulated under the hammers. Two cranes at the entrance to the
forge were used to move the axles out of the forge. The smaller crane loaded
axles on to the weighing machine while the yard crane loaded them on to the
flat bedded waggons known as `iron wains'.
At the southern end of the forge building is a reverberatory furnace with a
counter balanced lift door. The firebrick lined interior consists of two inter
connected chambers. At the side is the firebox, fitted with cast iron fire
grate bars upon which the coal fire burned. This furnace was moved from a
Sheffield steelworks and is similar to those used during the period of axle
production. A forced air blast was not provided for this type of furnace, a
natural draught being generated by means of a chimney stack and controlled by
a damper on top of the chimney.
To the south of, but attached to, the main forge building are two cottages
which are Listed Grade II. The cottages date to the early 17th century but
were later altered, probably in the 18th century at the time when the forge
underwent rebuilding. The cottages are of coursed rubble stone with a slate
and stone roof. They were once inhabited by workers of the forge but are now
used for display purposes as part of the museum and are excluded from the
scheduling, although the ground beneath is included.
To the south west of the main forge building, and at right angles to it, lies
the blacksmith and foundry building. This building, including the joiners
shop, is also now used for display purposes as part of the museum and is
excluded from the scheduling together with the machinery and the exhibits on
display, although the ground beneath is included.
A small roofed structure attached to the west end of the foundry building is
believed to be the housing for a cementation furnace and is included in the
scheduling. It is thought that during the 18th century, while under lease to
the Cockshutt family, steel was produced at the Top Forge using the
cementation process.
The former main office of the forge, now known as Forge Cottage, a Grade II
Listed Building, lies to the north west of the foundry building and is
excluded from the scheduling, although again the ground beneath is included.
The remains of the forge yard, the main entrance to the ironworking complex,
and the testing ground, all lie beneath the garden of Forge Cottege and are
included in the scheduling.
The water supply to the forge is provided by a complex water management system
which begins with a weir 90m west of Sharp Ford Bridge. The weir is a
substantial, stone built construction across the River Don. The head goit (the
channel which diverts water from the river to the forge) meets the river
immediately south of the weir. Water supply to the goit is controlled by a
sluice gate which is still visible at the head of the channel. From here water
flows directly to the forge dam although a second sluice gate further south
along the goit was also able to control the flow. For most of its course the
goit runs along the east side of Cote Lane. The forge dam is small in area,
only 2m deep at its maximum and clay lined. Along the head wall of the dam
there are three culverts to regulate the supply of water to the three wheels.
The overflow on the eastern side of the dam allows surplus water to return to
the river. Excess water would have been dangerous as it could damage the water
wheels or flood the forge itself. The small size of the dam was recognised
some time before 1746 when it was realised that there was insufficient water
for the regular running of the works. Consequently a new Back Dam was built
using the same head goit. It is possible that the water supply to the new dam
was provided by a pipe which ran from approximately half way along the length
of the head goit into the west bank of the Back Dam. The pipe is still visible
in both the east bank of the goit and the dam, although the middle section was
removed during the construction of a new fishing lake. A sluice at the
southern end of the Back Dam would have controlled the water supply between
the two dams. A sluice on the north east bank of the Back Dam would have acted
as an overflow and when opened would return water immediately to the river
which runs along the eastern side of the Back Dam. The banks of the dam are
lined with clay but on the north and east sides are revetted using dry stone
walling. The banks vary slightly in construction, the northern bank is
revetted with a vertical wall built of large rectangular stone blocks. The
upper courses of this wall have, very recently, been bonded with mortar in
order to strengthen the structure. The northern end of the eastern bank is
revetted using ironstone rubble at the base and vertical dry stone walling
above. Further south the east bank is built as a series of irregular steps
rising from the bottom of the dam.
Having passed through both wheels 1 and 2 and the blower wheel, two separate
tail goits take the water back to the river. The blower tail goit is joined
under the forge by another channel, which is thought to be the tail goit of a
former wheel a little to the east of the blower wheel. The tail goit from the
blower wheel turns sharply to the west just south of the cottages, and
continues in an open section of the goit, until it meets the river just east
of Forge Bridge. The other tail goit takes a very direct route to the river.
It was essential for industry further down the river that the water be
returned.
A narrow gauge railway runs along the southern edge of the monument and is
used for rides when the forge is open to the public.
A number of features are excluded from the scheduling; these are all modern
fencing, gates, metalled surfaces, the two cottages attached to the south of
the forge, the blacksmith and foundry building, Forge Cottage and the derelict
building to the south east of the forge, the machinery on display in the
blacksmith, foundry and joiners shop, the furnace and the water wheels in the
forge, and the narrow gauge railway to the south of the monument, although the
ground beneath all these features is included in the scheduling. The main
forge building and the roofed structure housing the cementation furnace are
included in the scheduling.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
