Reasons for Designation
By the late 19th century, Sheffield was one of the world's most influential
industrial cities. Underpinning its manufacturing base was the quality of the
steel it produced contributing to the international success of the city's
cutlery and edge-tool industries. A particularly significant development in
this supremacy was the invention, by Benjamin Huntsman in 1745, of crucible
steel: cast steel produced using crucible furnaces. This technique allowed
the production of high quality carbon steel of superior quality to blister
steel that was produced in cementation furnaces. This major technological
innovation secured Sheffield's economic position as a major metal trades
centre; the two manufacturing processes (cementation and crucible) together
were known as the 'Sheffield Methods'. By 1843 Sheffield was producing 90% of
British steel and almost 50% of European output. Although by later in the
19th century other countries had developed bulk steelmaking industries which
outstripped Sheffield in terms of quantity, the city retained its reputation
for quality with a wide range of special steels, the preferred means of
production remaining the crucible process which continued to be used up until
the 1970s.
In 1860 there were over 200 cementation furnaces in Sheffield of which only a
single example, in Hoyle Street, still survives in complete form. Over half
of their output of blister steel was then converted to crucible steel in
large numbers of crucible shops spread across the city. Darnall's large
crucible shop and continuous range of four small interconnecting crucible
shops with their ancillary rooms are unique survivals in Britain. The large
crucible shop is the sole remaining example of a building used to produce the
quantity of crucible steel required for large-scale castings, a method which
was generally superseded by new methods of bulk steel production in the later
19th century. Small crucible shops are also rare survivals with only fifteen
other small crucible shops remaining in the Sheffield area. None of these
other examples are organised as an integrated unit as are the four at
Darnall, and few are of such a complete state of survival. Although long
disused, the features that provide the technological and historical interest
of these buildings all survive well. The national importance of the monument
is further heightened by the in situ survival of archaeological remains. This
includes the remains of the Siemens gas fired crucible shop with its gas
plant which are of particular national significance because no other
surviving remains of a gas fired works are known to survive in the country.
The archaeological remains of the 1830s steel works are also of particular
interest as they will allow an understanding of the development of steel
production through the mid 19th century, complementing the evidence provided
by the later standing buildings. Any surviving remains related to the
cementation furnaces will be of particular importance given the very rare
survival of such furnaces nationally. The surviving standing structures
including the offices, boundary wall and entrance buildings, contribute
significantly to the site by allowing an appreciation of the character and
appearance of the original works, as well as an understanding of its
organisation. Any deposits of waste materials and discarded tools and
equipment will retain technological information that will compliment
surviving documentary evidence.
The Don Glass Works dates from a period of rapid growth in the glass
industry, when technological advances facilitated the mass production of
glass for a growing market. Glass has been produced in England since the
Roman period, although field evidence is scarce until the late medieval
period. From the early 17th century there was a change in the fuel generally
used from wood to coal resulting in a shift in glass production centres to
the coalfields, Sheffield and Barnsley being important areas for the industry
nationally. The manufacturing process involves three stages, fritting,
melting and annealing. Fritting was a common practice before the 19th century
involving heating the main glass constituents to produce an unmolten material
for grinding, melting and annealing. Melting involved the remelting of
previously formed glass, and the production of new glass from raw materials.
Until the late 19th century, glass was normally melted in pre-fired crucibles
of refractory clay, within the melting furnace. These melting furnaces were
typically circular with below ground flue systems which, from the mid 18th
century onwards, were covered by distinctive conical structures known as
glass cones. Only four standing examples of glass cones survive in Britain.
The third process is annealing: because the rapid cooling of molten glass can
give rise to internal stresses, glass was treated in furnaces designed to
heat the glass to a point where deformation begins, then cooled gradually.
Limited archaeological work at the Don Glass Works site in 2005 confirmed
that there is good potential for the survival of significant buried remains
such as the lower level of the glass cone complete with its below ground flue
system and other furnace features, together with ancillary buildings and
deposits of glassmaking waste and other material. This archaeological
potential combined with the documentary evidence for the site justifies its
inclusion within the scheduling. The association of the glassworks with the
establishment of Darnall steelworks provides additional interest with the
potential for surviving evidence of the cross fertilisation of technology
between glass and steel production in the mid 19th century.
Taken as a whole the monument represents a uniquely well preserved,
nationally important complex tracing the evolution of the site from an early
19th century glassworks to a 20th century steelmaking centre.
Details
The monument includes standing, earthwork and associated buried remains of a
steelworks established in the late 1830s, as well as the buried remains of a
late eighteenth century glassworks. The site retains its original boundaries
to the north (Darnall Road), east (Wilfrid Road) and south, but has been
partly truncated to the west in the 20th century by later steel works and
other redevelopment.
HISTORY Originally agricultural land in the 18th century, the Don Glassworks
is possibly the glassworks that was advertised for rent in the 1793 Sheffield
Register. It first appears, but is not named, on a survey of 1795 which
matches a more detailed plan of 1819. This 1819 plan labels the glassworks
and shows other details such as a short terrace of houses within the work's
plot to the east of the glass cone. In 1835 the glassworks was leased by
Sanderson Brothers, one of Sheffield's largest steel producers, who then
established Darnall Steelworks on adjacent land to the south. It is thought
that Sanderson Brothers leased the glassworks to aid their steel business,
learning from glass manufacturing technology, possibly adapting the glass
cone into a cementation furnace. However the glassworks, still shown by the
1853 Ordnance Survey map, reverted to glass manufacture by 1859 under the
management of Melling, Carr and Co., and ceased production, with the
demolition of the glass cone, by 1905. Sanderson's 1830s steelworks complex,
incorporating both cementation and crucible furnaces, was depicted in a
contemporary illustration and shown on the 1853 Ordnance Survey map. After
Sanderson's became a limited company in 1869, they abandoned their works at
West Street, Sheffield, and expanded their operations at Darnall. Additional
land was purchased and further crucible furnaces and administrative buildings
were built in 1871-2. This included two parallel ranges of small, single
storey crucible shops with a large crucible shop to the south. All of these
shops were coke-fired, providing a total of 132 melting holes, the large shop
housing 48 melting holes, with the small shops having 12 each. In 1873-4 a
Siemens gas-fired crucible shop, complete with an adjacent gas production
plant, was built to the west of the large coke fired shop. This gas-fired
shop was about the same size as the coke-fired large shop and provided the
equivalent capacity of 60 coke-fired melting holes. In 1934 Sanderson's
passed their Darnall works to Kayser Ellison, the operators of the steelworks
on land immediately to the west that was established in 1913. Kayser Ellison
used electric arc furnaces and although they operated the older Darnall works
plant for a while, soon switched to all-electric melting, expanding their
works with the demolition of the 1830s cementation furnaces, which had been
working into the 1920s, and the western range of small 1870s crucible shops.
In 1960 a company merger resulted in the whole complex being operated by
Sanderson Kayser Ltd. Following the merger, the gas-fired plant was
demolished, but its site was not redeveloped and significant buried remains
are believed to still survive in situ. Alterations were also made to some of
the small crucible shops, such as widening of doorways and removal of
interior fittings, to adapt them for re-use as stores. By the end of the 20th
century steel production had ceased at Darnall with the surviving 19th
century buildings either derelict or used for storage.
The monument has been the subject of a number of archaeological, building
recording and historical studies. This includes survey and small scale
evaluation excavations of the glassworks site and the 1830s steelworks which
confirmed the survival of in situ archaeological remains. The standing
crucible shop buildings were recorded by English Heritage in 2003 and the
whole complex, including the former Kayser Ellison Works to the west of the
monument, was the subject of a pilot study (from 2004), for the Government's
review of Heritage Protection Legislation. More detailed description of the
various parts of the monument can be found in these earlier studies.
DESCRIPTION Access to the Sanderson's Works was from Darnall Road, close to
the junction with Wilfrid Road. Extending inside from the boundary wall
flanking the entrance is a 2-storey gate lodge and a single-storey
weighbridge office. Both are believed to date to the 1870s and are included
in the scheduling as well as being Listed at Grade II. The boundary wall,
which also extends up Wilfrid Road and is thought to date to this time, is
also included in the scheduling. A short distance up the hill to the south
east of the main entrance is the two-storey former office building. This
Grade II listed building, again included in the scheduling, also formed part
of the 1870s expansion of the works. Probably designed to impress clients, it
has some architectural embellishment provided by Venetian windows and other
decorative features. The glassworks, with its ancillary yards and related
buildings, occupied the area of the monument to the west of the steelworks
entrance. The eastern part of the glassworks plot shown on the 1795 map was
later given over to housing, probably for workers employed at the glass and
steelworks, but possibly also including small scale workshops. This area is
considered to include archaeological deposits related to the earliest phases
of the glassworks and is thus also included in the scheduling. Following the
demolition of the glassworks, its site was occupied by an edged tool works
which has also been subsequently demolished along with the former housing.
However, ground surfaces here have been raised so that significant in situ
remains of the glassworks and other features related to the use of the site
by the steelmakers Sanderson Brothers are believed to survive over much of
this area. A small scale evaluation excavation in 2004 confirmed survival of
in situ remains. The 1830s steelworks was formed around a rectangular yard
just up hill to the south west of the later office building. Forming the
north western side of the yard was a building housing four cementation
furnaces which was demolished sometime after 1935. On the opposite side of
the yard was a range including six crucible shops, probably each with 6
melting holes. Although these shops were demolished before 1891,
archaeological investigation in 2002 demonstrated the in situ survival of
their vaulted cellars, including large quantities of crucible and other steel
manufacturing material. Within the area of the monument, land surface levels
have not generally been lowered. Further significant remains of the 1830s
steelworks are thus considered to survive archaeologically and are included
in the scheduling.
Uphill and to the south west of the 1830s steelworks, the two parallel ranges
of small crucible shops were constructed in the early 1870s. The longer,
eastern range still survives as standing buildings (listed at Grade II*) and
are included in the scheduling. The western range has been demolished with
most of its former footprint lying outside the area of the monument, within a
part of the original site where the land surface has been significantly
reduced. The surviving eastern range is complete with only minor alterations.
It is single storey, brick built, and is of 23 bays stepping up the hillside.
In plan the range consists of four crucible shops with eleven ancillary
rooms, all linked internally by a passageway running behind the front wall,
accessed from the yard through doorways at various points in the front
elevation. The layout suggests that the row worked both as a series of
individually accessed industrial units (the crucible shops, each with its own
charge room) but also sharing resources, particularly the manufacture of
crucibles and storage space. Each crucible shop had two opposing stacks built
transversely across the row, with the main casting floor between where the
molten steel was cast into moulds. Each stack has flues for six melting holes
where the crucibles were heated to melt the steel, and one of the pair also
has an annealing furnace, (a lower temperature furnace used for tempering or
hardening the steel). The southernmost crucible shop retains its iron plate
floor covering, infilled melting holes and casting pits, along with hatches
providing access to the cellars which contain the ash-pits for the melting
holes. Crucibles, hand-made out of refractory clay and other clays, lasted at
most a day in use and consequently their constant manufacture was an integral
part of the functioning of crucible steelworks. Many of the ancillary rooms
are related to their manufacture. At the centre of the row is a wet clay
store which is flanked by two pot shops where the crucibles were made. These
pot shops also separate the wet clay store from any heat source. Between each
pair of crucible shops are two unlit narrow bays which are thought to have
been crucible curing rooms, utilising the heat from the cross walls formed by
adjacent stacks to dry out the crucibles prior to use. On the other side of
each crucible shop is a charge room for the storage of fuel for the furnaces.
Other ancillary rooms were probably used for general storage.
At the south end of the range of small crucible shops are a further four bays
which form ancillary rooms to the large crucible shop that extends to the
north west and which is also Grade II* Listed as well as being included in
the scheduling. This double height building was designed to enable the
casting of large items using the continuous teeming method, whereby a large
number of crucibles were poured in rapid succession into a single mould. The
large shop allowed an increase in the scale of castings by having a greater
number of melting holes next to a larger working floor than provided in the
smaller crucible shops. The internal arrangement is also different in that
the stacks run lengthways, rather than across the building, and are inset
from the outer walls so that narrow side aisles are formed between the stacks
and the outer sidewalls. Most of the internal space of the building is taken
up by the large casting floor, served by a timber crane and flanked by 48
evenly spaced melting holes, 24 each side divided into two groups of 12
either side of a central arched opening through the stacks. At both ends of
each stack there is also an annealing furnace. On the lower inner face of the
stacks are three rows of metal brackets for shelving, on which the crucible
pots would have stood before use. Further shelf brackets and other features
survive on the other side of the stacks within the narrow side aisles which
formed ancillary rooms. Two cellars, accessed from outside the building, run
longitudinally underneath the melting floor and contain individual ash-pits
for the melting holes above. The building was entered by three
symmetrically-placed doorways in the front, north eastern, elevation and the
centrally-placed north-west gable doorway. The four ancillary rooms to the
south east of the crucible shop include a pot shop, a wet clay store and a
charge room, with a room of unknown use in the south-eastern corner
containing two inserted furnaces. The pot shop, where crucibles were
manufactured, retains its stone-built treading tray where clay was processed
by being trodden under foot. It also retains the brackets for storage
shelving for new crucibles.
To the west of the large crucible shop was the 1873-4 Siemens gas-fired
crucible shop with its associated gas production plant. Part of the rear wall
still survives, acting as a retaining wall to the hillside to the south.
Cellars, wall footings and other features of technological interest of both
the crucible shop and gas plant are considered to survive as in situ
archaeological remains. Evidence of these structures has been revealed during
various groundwork operations in recent years and they are thus included
within the scheduling. To the west of the site of the gas plant is an
infilled former quarry which is shown as being part of the steelworks on
historic maps. This area is specifically included within the scheduling for
its potential for retaining large quantities of discarded tools, waste and
other material from the steelworks. These deposits also have the potential of
retaining highly significant technological information about steel production
in the 19th to 20th centuries that will complement documentary evidence. The
original southern boundary of the works was just beyond the south exterior
walls of the large crucible shops. The boundary of the monument follows this
original works boundary to include evidence of any auxiliary structures as
well as to ensure future access to the rear wall of buildings included in the
scheduling for maintenance purposes.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
