Reasons for Designation
Limestone or chalk has been the basic ingredient for lime mortar from at
least Roman times. Since the medieval period, lime has also been used as
agricultural fertiliser and, since the early 19th century, widely used in
a variety of other industries: as a flux in blast furnaces, in the
production of gas and oil, and in the chemical, pharmaceutical and food
industries.
The lime industry is defined as the processes of preparing and producing
lime by burning and slaking. The basic raw material for producing lime is
limestone or chalk: when burnt at high temperature (roasted or calcined),
these rocks release carbon dioxide, leaving `quicklime' which, by chemical
reaction when mixed with water (`slaking'), can be turned into a stable
powder - lime. Lime burning sites varied in scale from individual small
lime kilns adjacent to a quarry, to large-scale works designed to operate
commercially for an extended market and often associated with long
distance water or rail transport. Lime burning as an industry displays
well-developed regional characteristics, borne out by the regional styles
of East Anglia, West Gloucestershire or Derbyshire.
The form of kilns used for lime burning evolved throughout the history of
the industry, from small intermittent clamp and flare kilns, to large
continuously fired draw kilns that could satisfy increased demand from
urban development, industrial growth and agricultural improvement.
Small-scale rural lime production continued in the later 19th and 20th
centuries, but this period of the industry is mainly characterised by
large-scale production and the transfer of technologies from the cement
and other industries. The demand for mortars grew steadily during the 19th
and 20th centuries. The successful production of mortars made with
artificial cement represented an economic challenge to lime production and
gradually replaced the use of lime mortars in major construction and
engineering projects.
From a highly selective sample made at national level, around 200 lime
industry sites have been defined as being of national importance. These
have been defined to represent the industry's chronological depth,
technological breadth and regional diversity.
Twiston lime kiln survives well and is an excellent example of a large
19th century roadside lime kiln. It is a rare example in north west
England of a lime kiln complete with the remains of an associated tramway.
Details
The monument includes a large 19th century roadside lime kiln and
associated tramway, located on the south side of Twiston Lane, 250m east
of Twiston Mill. It is a single pot draw hole type kiln which was used to
burn limestone. Typically the limestone was tipped into the kiln from the
top via the charge hole then burned using wood, coal or coke as a fuel.
The resultant quicklime, also known as birdlime or slaked lime, was then
shovelled out from the draw hole at the bottom of the kiln. Lime has many
uses including spreading on lime deficient soils to encourage plant
growth, the whitewashing of walls and ceilings of buildings, and concrete
and cement production.
The lime kiln is a flat-fronted structure approximately 7m high which is
constructed of randomly coursed limestone and sandstone and is built into
the hillside. Its draw arch which leads to the draw hole, also known as
the fire hole, is segmental and measures about 4m wide amd 2m high.
Flanking the draw arch is a part-keyed buttress on the west side and a
curving retaining wall which also acts as a buttress on the east side. The
charge hole measures approximately 6m in diameter and is largely infilled.
To the south west of the charge hole there are the earthwork remains of a
tramway along which stone was carried in tubs or wagons along rails laid
on an earth and stone embankment from the adjacent quarry to the kiln. In
its present form the tramway embankment measures about 30m long by 2m wide
and up to 0.3m high but peters out as it approaches the charge hole.
All fences and fence posts are excluded from the scheduling, although the
ground beneath them is included.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
