Blowing mill 260m south east of Teignhead FarmList Entry SummaryThis monument is scheduled under the Ancient Monuments and Archaeological Areas Act 1979 as amended as it appears to the Secretary of State to be of national importance. This entry is a copy, the original is held by the Department for Culture, Media and Sport.
Name: Blowing mill 260m south east of Teignhead Farm
List entry Number: 1019217
Location
The monument may lie within the boundary of more than one authority.
County: Devon
District: West Devon
District Type: District Authority
Parish: Dartmoor Forest
National Park: DARTMOOR
Grade: Not applicable to this List entry.
Date first scheduled: 09-Feb-2001
Date of most recent amendment: Not applicable to this List entry.
Legacy System Information
The contents of this record have been generated from a legacy data system.
Legacy System: RSM
UID: 28757
Asset Groupings
This list entry does not comprise part of an Asset Grouping. Asset Groupings are not part of the official record but are added later for information.
List entry Description
Summary of Monument
Legacy Record - This information may be included in the List Entry Details.
Reasons for Designation
Dartmoor is the largest expanse of open moorland in southern Britain and, because of exceptional conditions of preservation, it is also one of the most complete examples of an upland relict landscape in the whole country.
The great wealth and diversity of archaeological remains provide direct evidence for human exploitation of the Moor from the early prehistoric period onwards.
The well-preserved and often visible relationship between settlement sites, major land boundaries, trackways, ceremonial and funerary monuments as well as later industrial remains, gives significant insights into successive changes in the pattern of land use through time.
Blowing mills (also known as blowing houses) survive as rectangular drystone buildings served by one or more leats and are characterised by the presence of granite blocks with moulds cut into them - bevelled rectangular troughs known as mould stones - and on occasion by the square or rectangular stone built base of the furnace itself.
During the medieval and early post-medieval period, black tin (cassiterite) extracted from streamworks and mines was taken to blowing mills to be smelted. At the blowing mill the cassiterite may have been washed a final time before being put into the furnace together with charcoal.
To smelt tin the temperature within the furnace had to reach 1150 degrees C.
This was achieved by blowing air through the furnace using water powered bellows. Once the tin had become molten, it flowed from the furnace into a float stone and was ladled into the mould stone, in which it cooled to form an ingot of white tin. The original number of blowing mills on Dartmoor is unknown, but at least 26 are believed to survive, whilst a further 41 are known only from stray finds and documentary sources. All examples with a clearly identifiable surviving structure are therefore considered to be of national importance.
The blowing mill 260m south east of Teignhead Farm survives well and is one of only seven examples known to contain a furnace. Important information concerning tin smelting technology survives within and around this building. The unusual mould stones containing two troughs and the particularly large furnace block are of special interest.
The blowing mill 260m south east of Teignhead Farm survives well and is one of only seven examples known to contain a furnace. Important information concerning tin smelting technology survives within and around this building. The unusual mould stones containing two troughs and the particularly large furnace block are of special interest.
History
Legacy Record - This information may be included in the List Entry Details.
Details
The monument includes a tin blowing mill situated at the foot of a steep 3m high scarp adjacent to the North Teign river. The mill building is of drystone construction with the wall standing up to 0.8m high. The interior of the mill measures 13.6m by up to 3.5m and access to it was through a clearly mill, two edge set stones represent the site of the furnace, in which the black tin (cassiterite) was smelted. A hollow adjacent to the northern wall denotes the position of the wheelpit in which a wheel powered by water operated the furnace bellows. Molten tin from the furnace was ladled into a large mould stone, containing two separate troughs which stands next to the furnace. A second broken mould stone lies within the entrance. A 5.5m long by 2.3m wide rectangular structure is attached to the south eastern end of the mill building. This is defined by a rubble wall of varying height and width standing up to 1.2m high. In the area south of the mill there is a series of earthworks, some of which are the result of earlier streamworking, but others may relate to dressing and washing activities. Beyond these earthworks and adjacent to the river is a drystone wall of 19th century date. Built into the top of this, a broken mould stone and mortar stone are clearly visible. These features are included in the scheduling
MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.
MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.
Selected Sources
Other
Devon County Sites and Monuments Register, SX68SW46, (1995)
MPP fieldwork by S. Gerrard, (1999)
Devon County Sites and Monuments Register, SX68SW46, (1995)
MPP fieldwork by S. Gerrard, (1999)
National Grid Reference: SX 63768 84271