Summary
The monument includes the standing, earthwork and buried remains of Middle Engine Pit, a coal mine established in the late C18. It was updated in about 1860 and production ceased around 1870. The monument also includes several early-C20 garden features associated with a house which was built adjacent to the former mine.
Reasons for Designation
Middle Engine Pit, a colliery that operated from around 1790 until the 1870s, is scheduled for the following principal reasons:
Survival: it is an early example of a pithead complex that retains clear evidence for its historical development and technological improvements carried out during the lifetime of the mine. The incorporation of some mine structures within an Edwardian semi-natural garden ensured their survival and adds to the interest;
Diversity: it includes a range of ruined buildings, earthworks and buried archaeological remains which, together, preserve the surface history of the coal industry during this period;
Potential: the monument has good potential for aiding our understanding of late-C18 and C19 mining technology;
Documentation: it is well-documented in historic sources and through archaeological investigations and these enhance our knowledge of the monument;
Group value: for its historic relationship with the area’s glass-making industry, in particular with the nearby Nailsea Glassworks which is also scheduled.
History
Within Britain, coal occurred in huge deposits over vast areas and gave rise to a variety of coalfields that extended from the north of England to the Kent coast. The technology of coal mining became increasingly complex over time with the gradual mechanisation of many mining operations, including the application of steam winding and pumping from the late C18 which gave access to greater quantities of coal at greater depths.
The Nailsea coalfield is an outlier of the larger Somerset coalfield, and its coal seams were worked from the C16, albeit on a small scale, mostly supplying local demand. Middle Engine Pit, latterly known as Elms Colliery, was one of a group of small collieries that developed around Nailsea in the late C18 and early C19 to serve the local glass-making industry. Many of the mines, including Middle Engine Pit, where coal extraction may have begun around 1790 (Lambert-Gorwyn), were run by a partnership of local men. John Robert Lucas the owner of nearby Nailsea Glassworks joined the partnership in 1788. When the partnership was renewed in 1807 an agreement was signed that the glassworks would receive coal from the partnership in exclusivity for the next 30 years. This arrangement appears to have remained in place until 1842.
Middle Engine Pit is shown on the tithe maps for both Wraxall and Nailsea, dated 1837 and 1840 respectively. The Wraxall map does not include any detail of the site apart from its boundary, recording in the accompanying apportionment that it was a ‘Coal Yard’ owned by Sir John Smyth; leased to R H Bean; and occupied by H White. The Nailsea map depicts a group of pithead buildings, a rectangular building which may have been workers’ housing to the north-west, and a possible reservoir to the south. It appears to also show, based on their characteristic plan, two horse gin which would have been used for raising and lowering men and materials to and from the workings. The mine is described in 1840 as ‘Engine Yard & Building’. At the time it was owned by Sir John Smyth and Sir Reginald Bean and leased to White & Company. The mine was probably served by a tramway which approached from the north, though this is not depicted on either tithe map. In 1848 the plant at Middle Engine Pit was described as ‘pumping engine with open top cylinder’ ..…’One haystack boiler 15 feet diameter’….. ‘Engine house not included being leasehold…£800. Winding Engine’…One haystack boiler 10 feet diameter with winding apparatus’….’Engine House not included being leasehold…£500.’…’Tram plates underground and Top…£25 (City of Hereford Archaeology Unit).’ In about 1860 the mine was updated. The whims were replaced by a steam winding engine within a new engine house to the south-east of the shaft; the existing pumping engine house was modified for a new engine, probably a 50” Cornish type; and the pumping engine boilers were also replaced.
Coal production at Middle Engine Pit appears to have ceased around 1870, and the plant and land were subsequently sold. By the turn of the C20 a house, known as The Elms, had been constructed in the western part of the site. It was situated in the same location as a mine building shown on historic maps and it may have been incorporated into the new dwelling. Gardens were laid out to the east and north-east on the site of the mine, which was landscaped and planted with trees. Several ponds were also created. Some of the mine buildings were demolished, but several were retained. The winding engine house was altered and raised to accommodate a water tower that supplied water to the house and garden, and the whims appear to have been adapted to garden features. The Elms was demolished in 1985 and the land surrounding Middle Engine Pit was subsequently built over.
The remains of Middle Engine Pit were surveyed and excavated in 1984-1985, prior to the development of the surrounding land for housing. The surviving mine structures were listed at Grade II in 1985 and the site was scheduled the following year. Archaeological recording was carried out in 1996, and some consolidation has since been undertaken.
Details
PRINCIPAL ELEMENTS
The monument includes the earthwork, standing and buried remains of Middle Engine Pit, a late-C18 coal mine. The mine was updated in about 1860 and it closed around 1870. The monument also includes several garden features associated with a house that was built adjacent to the mine at the turn of the C20. It is situated to the south-east of Nailsea town centre, within a residential area that was developed in the late C20.
DESCRIPTION
Historic maps and archaeological investigations, along with the earthworks and standing remains, provide evidence for the layout of the mine. In the central, western part of the site is the main shaft around which many of the buildings were grouped. The shaft appears to have been used for pumping and winding; it is 5m in diameter and lined with stone rubble. It has been largely infilled and capped with a metal grille. The pumping station on the west side of the shaft was found to be a rectangular structure with substantial sandstone walls and an internal pit some 2.5m deep. Some low sections of walling are visible, and the foundations survive below ground. A quantity of chain links were found during the excavation and are thought to have come from the beam ends of the original pumping engine. In front of the east bob wall is a stone-lined pit, possibly a condenser pit, that has been infilled. The boiler houses which flank the pumping engine house are of at least two phases and survive in places as footings, though much overgrown. The western half of the north boiler house is not extant as a result of the adjacent residential development (6 Caversham Drive). The buried remains of brick flues, ash pits and stone steps leading to ash-rake tunnels beneath the buildings were uncovered during the excavation.
Immediately east of the shaft are the remains of a horse gin which provided an early means of raising coal at Middle Engine Pit. It is a raised circular feature some 10m in diameter and approximately 1.5m above the present ground surface. It is made up of layers of coal waste and clinker, with a thinly-coursed, stone rubble retaining wall around all but its west side. The south section of walling has collapsed. A short flight of steps lead onto the horse gin and are a later feature associated with its re-use as a garden feature in the early C20. The excavation uncovered the original surface of the horse gin and also a masonry plinth at the centre which has been interpreted (Lambert-Gorwyn) as the base for the vertical axle that held a gin arm or pole powered by a horse or horses which rotated a winding drum to raise coal from the shaft. Against the north side of the horse gin are the fragmentary remains of a small stone building that has been interpreted as a candle store. Some 28m to the south-east of the main shaft is a second shaft that was probably used for winding and possibly for ventilation (City of Hereford Archaeology Unit). There is no surface evidence for the shaft, but its approximate location is marked by a former pump house built to pump water from the mine workings to provide a domestic supply for The Elms, the house constructed in the western part of the mine at the turn of the C20. It is a small, single-storey, roofless building with consolidated stone rubble walls, window openings to the north and south sides, and a doorway in the east gable wall. Immediately to the south is a second horse gin which survives as a low circular enclosure approximately 9m in diameter that was previously surrounded by a sandstone rubble wall. A section of the wall is visible at ground level but most of the stone has been robbed. the area around the levelled gin circle was built up with coal waste, slag and soil in the early C20 to create a small orchard.
The method of using a horse gin for winding at Middle Engine Pit was replaced in about 1860 when the now roofless engine house (listed at Grade II) was built to accommodate a steam-powered beam winding engine. The headgear is not extant, but the remains of its support walls, capped with sandstone slabs, survive between the engine house and the shaft. The engine house itself is the best-preserved of the mine buildings and is constructed of random pennant sandstone rubble with dressed quoins, with some evidence of repairs. The upper section was added in the early C20 and is built of rendered brick and has an iron downpipe and hopper-head. The south-east elevation contains an inserted doorway with a timber lintel and a blocked window above; the north-east elevation has several infilled windows and an original entrance which has since been altered to a window; and there is a window in the south-west side. The engine house originally had three storeys, with the main working area at first-floor level; the stone base for an external winding drum survives on the north-west side of the building. Parallel to the north-west side of the engine house are the fragmentary remains of a boiler house which is probably of two phases of construction. Stone walls up to 1m high are evident, and the foundations which were identified during the excavation survive below ground. The chimney is not extant.
In the northern part of the site, close to the entrance of the mine complex, is a small rectangular, single-cell building that may have originally been a check house or office. It is roofless and has a doorway in its south wall, and blocked windows in the north and west sides. Internally, there is evidence for a fireplace. The land associated with the mine originally extended to the north of this building and to the west of the pumping engine house where The Elms and its outbuildings previously stood, but both these areas have been redeveloped.
Early-C20 garden features associated with The Elms, which was demolished in the 1980s, include the remains of dwarf stone walls and a short flight of steps in the southern part of the site, and two small concrete-lined ponds. Along the south and south-east boundaries of the site are the fragmentary remains of a sandstone rubble wall up to 1m high in places. It has no diagnostic features and it is likely to be early C20.
EXTENT OF SCHEDULING
The monument boundary has been drawn to include the known extent of nationally important colliery remains and is for the most part defined by the boundaries to the houses that surround the site except to the east and south-east where a stone wall and metal railings define the monument and separate it from a pedestrian footpath.
EXCLUSIONS
The steel railings, timber fencing and posts, Heras fencing, the early-C20 boundary wall, and the metal grille capping the shaft are all excluded from the scheduling, but the ground beneath these features, however, is included.
