The tunnels and portals of the Offham funicular railway/tramway.
Reasons for Designation
The tunnels and portals of the Offham funicular railway/tramway built in 1809 are listed at Grade II for the following principal reasons:
* Architectural and technological interest: the eastern portal is a monumental structure displaying engineering skill and adroit construction. The parallel tunnels bear witness to the operational method of the funicular tramway/railway;
* Historic interest: the tunnels and portals are the standing remains of a funicular tramway/railway dating to the early years of rail transport;
* Relationship with setting: the portals and tunnels relate to the remains of other contemporary (but undesignated) structures associated with the Offham lime works.
THE LIME INDUSTRY
Lime 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 C19, 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 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 kiln 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 C19 and C20, 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 C19 and C20. 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.
HISTORY OF TRAMWAYS
The first recorded use of a waggonway or tramway to transport materials in an industrial context in England is thought to be that at Wollaton Hall, Nottingham in 1597. It was horse drawn, ran on wooden rails and was used to transport coal. Iron rails were introduced by the Coalbrookdale works in 1767 and were used on a number of industrial sites in the late C18, notably in collieries and from 1800 a large network of iron-rail tramways were in existence in south Wales. An early exponent of iron rails, William Jessop (1745-1814) used them in 1789 on a line between Nanpantan and Loughborough in Leicestershire before he went on, as a partner in the Butterley Iron Works, to design the Surrey Iron Railway. By the early C19 waggonways or tramways (not all using iron rails) were in common use on industrial sites, such as the granite tramway of the 1820s at the granite extraction quarries at Haytor on Dartmoor.
EARLIER CHALK PRODUCTION ON OFFHAM HILL
Chalk had been produced from quarries on Offham Hill since the medieval period, but in the C18 it was quarried on a larger scale. During the second half of the C18 the population growth of England and Wales created an increased demand for food and housing, both of which demanded lime, the former for liming fields in order to increase productiveness and the latter in the production of plaster, mortar and cement. In response to this demand locally a number of chalk pits along the Sussex Downs escarpment were opened or enlarged. Chalk from the large quarry nearest to Offham was transported to Landport by horse and cart and down to a barge wharf, which had been cut in the 1790s, for further distribution.
THE OFFHAM LIME WORKS
George Shiffner, an industrialist, and M.P. for Lewes from 1812 to 1826, in 1801 opened a new quarry and lime works on Offham Hill. By 1807 he had persuaded William Jessop Jnr. to link his new lime works to the new canal system which the latter had been building. This link was created via an inclined plane bearing a tramway and a new wharf at a branch of the Upper Ouse Navigation known as Chalkpit Cut. The tramway was completed by 1809 and is thought to have been the first railway in southern England and the first inclined railway in Sussex. John Murray in his ‘Handbook for Travellers in Kent and Sussex’ (1858, 276) observed here 'the remains of what claims to be the first bit of railway executed in the south of England'.
When the lime works was operational the chalk hewn from the quarry at the west end of the site was moved by horse-drawn wagon to a bank of kilns in the middle of the site. Chalk and fuel were loaded into the kilns, each of which was basically a brick chamber with a hearth at the base. Chalk and fuel were loaded from a ramp into the top of each kiln, and, after burning, lime was drawn off at the base. This lime and probably raw chalk also, was loaded onto wagons at the east end of the site. The wagon track passed under the road, which is now the A275 (a former turnpike road), via two tunnels, one for the descending wagon and one for the ascending one. It is thought by Martin from map and site evidence that the loaded wagons ran on the northernmost track and the unloaded ones on the southernmost track. Martin also notes from map evidence that the southernmost track is shown as stopping at the lane at the bottom of the incline, but that the northernmost track continues across the cut to a circular shape on the east bank. It is thought that this track was carried over the cut in the form of a wharf, and that the circular area was a support for the end of the structure. The wagons were attached to pulleys and a fly wheel in the brake house at the head of the incline, and the unloaded wagons at the base of the incline drawn to the top again by the counterbalance of the loaded wagons descending from the top. At the base of the incline the chalk and lime were unloaded onto barges at the specially constructed wharf. Michael Robbins in his article ‘The First Sussex Railway’ (Railway Magazine, 1971) shows a map with a building at the bottom of the incline. This appears to have been a tally house where the quantity of chalk and lime was recorded before transfer to the barges, or a wharf structure concerned with the transfer of chalk and lime to barges.
The quarry went out of use about the turn of the C19 century; it may have stopped operations about 1890, although since Murray observed ‘the remains of the railway’ in his 1858 publication, it may have been earlier than that. The tramway is still shown on an OS map of 1899, but absent by the time of the 1910 map.
The tramway includes two parallel tunnels which take the track bed underneath the A275. These tunnels slope downwards from west to east with an incline of 1 in 3.5 and are 22m long. The tunnels have slightly flattened semi-circular barrel vaults which are separated from each other by a brick wall 0.45m thick. At the west end of the tunnel the entrance is about 1.5m from ground level to crown of vault, and at the east end is 8m from ground level to crown of vault. The internal height of the tunnels is about 2m from track bed to crown of vault, although this is an estimation since there is a substantial build-up of soil within each of the tunnels, particularly at the west end where clearance between soil build-up and crown of vault is greatly reduced. The interior of the tunnels appears to be lime wash or plaster rendering over red brick.
The faces of the walls above the tunnel entrances are battered to about 13 degrees from the vertical. That to the west end is of red brick in English Bond construction with a soldier course at the top. The face of this end of the tunnels has been repaired using mainly new bricks but with a few original bricks.
At the east end the central 1809 tunnel walls are in header bond and have three later supporting buttresses. Flanking this central area are retaining walls which are extended at both the north and south sides and of mixed construction, some parts underpinned by concrete. The lowest part of the retaining walls are constructed of flint rubble and are thought to pre-date the tramway as they are battered to a steeper angle than the tunnel entrances. The upper part of this east face of the tunnel entrance and retaining wall is topped by a later phase of brick construction in English Bond with a thick parapet wall surmounted by a cement coping. Iron gates bearing the date 1809 were erected at the entrance to the east portal in 1994 by East Sussex County Council.