H M Prison Dartmoor: Polygonal buildings, former officers' mess and former steward's house, now admin building and visits building

Summary

Two polygonal prison buildings dating from 1806-9 designed Daniel Alexander, with later additions and alterations, having a much altered mid-C19 block attached to the north of the northern building, and a 1909 block to the south of the southern building.

Reasons for Designation

The polygonal buildings, former officers' mess and former stewards' house, now admin building and visits building, H M Prison Dartmoor, is listed at Grade II for the following principal reasons:
* Historic interest: an integral part of the historic Dartmoor Prison complex, originating in 1806-9, the polygonal buildings served as observation buildings and stores, whilst this group includes the former gatekeeper’s/steward’s house, and the 1909 officer’s mess;
* Architectural interest: despite alteration, the form of the polygonal buildings is recognisable as part of Daniel Alexander's original design, and reflects their original purpose, overlooking the former marketplace; the Edwardian former officer’s mess is shows some architectural consideration within the prison context;
* Group value: the buildings form part of an important and relatively complete group of listed prison buildings, together reflecting the historic development of H M Prison Dartmoor and its distinctive radial plan form as first envisaged in 1806-9.

History

Dartmoor Prison was built by the Admiralty in 1806-9 on land leased from the Duchy of Cornwall, to receive prisoners of war. During the Napoleonic Wars of 1803-15 there were 47 prisoner of war hulks moored at Chatham, Portsmouth and Plymouth, and pressure on Plymouth was increased when prisoner of war prisons at Norman Cross, Northamptonshire and Stapleton near Bristol became full. The London architect Daniel Asher Alexander (1768-1846), was employed to design Dartmoor Prison.

The first inmates were received in May 1809, and by June that year the prison housed 5000 prisoners of war. As described in Risdon’s Survey of Devon (1811), and illustrated by two views by Samuel Prout (1809 and 1811), by a drawing in Ackermann’s Repository of 1810, and by a survey drawing of the prison of 1847, Dartmoor Prison originally consisted of five blocks laid out in a radial arrangement around a central market place, in total covering c12ha and surrounded by a double, circular perimeter wall. Internal walls divided the prison into a number of sections. In the central market place prisoners could trade with outside traders. The western part of the prison included an Infirmary and a separate Petty Officer’s Prison. The main entrance of the prison was flanked to the right by the Governor’s House and to the left by the Surgeon’s House. In 1812, following the outbreak of the trade wars with America, two blocks were added to house prisoners, and the Petty Officer’s block was converted into a barrack to supplement the large barracks complex south of the prison. The prison closed in 1816. Despite the opening of a railway from Plymouth to Princetown in 1827, the area saw little economic development following the prison closure.

In 1850 the prison re-opened as a civilian prison to address the contraction in the transportation of prisoners to Australia; alterations were made to the accommodation, and by 1851 there was room for 1030 inmates. During the 1860s, 1870s and 1880s a number of alterations were made to the prison by the architect Sir Edmund du Cane (1830-1903), appointed Director of Convicts and Inspector of Military Prisons in 1863, and Surveyor-General of Prisons, Chairman of the Board of Convict Prisons and Inspector-General of Military Prisons in 1869. Further rebuilding of the prison took place during the first quarter of the C20, with four new wings built between 1901 and 1915. A detailed description of Dartmoor Prison during this period was published in 1909-10 by RG Alford (Notes on the buildings of English Prisons, vol. 2, pp75-87).

During the First World War Dartmoor Prison housed around 1000 conscientious objectors, who mainly undertook farm labour or worked in quarries on the Moor.

Dartmoor Prison has seen much change in the course of the C20 and early C21. Major prison riots which took place in prisons across the country including Dartmoor in 1990, led to an extensive refurbishment programme to improve the prison’s security. Despite the degree of rebuilding which Dartmoor has undergone over more than two hundred years, the radial plan established by the original design has survived.

The two polygonal buildings standing to west of the former market place date from the first phase of building, circa 1806-9. These flanked the entrance to the market place, and there was formerly a gateway between them. The polygonal form was presumably intended to facilitate observation over a wide area. It is not possible to be certain about their original form since early illustrations differ in their representation. The buildings appear originally to have been hexagonal, with canted ends to the east, overlooking the marketplace, and squared ends to the west; their pyramidal roofs had central lanterns, with the one to the south visible in an aerial photograph of 1953. In the mid-C19 the building to the north was a gatekeeper’s house, standing between the gateway to the market place, and the gateway to the infirmary compound, and the building to the south was partly a store, and partly given over to cells. The western part of the northern building, with additional building to the north, became the steward’s house, whilst in 1909 an officers’ mess was built to the south of the southern building. In 1927 both eastern polygonal sections were stores; by 1948, the officer’s mess was a workshop, whilst the whole of the northern complex was in use for visits. There are now offices in the southern building, whilst the northern building is still used for visits. All parts of the buildings have been much altered, with recent work to the window openings to the polygonal sections.

Details

Two polygonal buildings, with canted ends to the east, and squared blocks to the west. These date from the first phase of building, 1806-9, to a design by Daniel Alexander, but have been added to and altered since, with a much altered mid-C19 block to the north of the northern building, and a 1909 block to the south of the southern building.

MATERIALS: coursed granite rubble, with replacement ashlar window surrounds, and replacement frames. The roofs are metal; the roofs to the polygonal sections are pyramidal, with finials.

PLAN: the polygonal buildings stand to north and south of the entrance to the former marketplace, with canted ends facing into the former marketplace to the east. They extend westwards, ending in squared west ends. Both buildings have later attached structures: the southern building has the large block built as an officer’s mess to the south, and the northern building has a much altered section to the north.

EXTERIOR: the two polygonal buildings stand on granite plinths. The polygonal sections have large triangular-headed windows to the first floor, overlooking the former marketplace, probably reflecting their original form. The other windows are small. The southern building is entered from the north-east and from the south; the northern building has blocked openings to the south-facing elevation, and a new secure entrance in a lean-to addition against the west wall of the former steward’s house. There is another late-C20 extension projecting westwards from the north end of this building. The former officer’s mess to the south is a two-storey building with four pairs of basket-arched windows with granite surrounds, and an attached central chimney.

INTERIORS: the interior of the northern building has been opened out, with no division between the polygonal part and northern range; it is thought that few historic features, though the bottoms of roof timbers appear to be visible in the polygonal part. The interior of the southern building was not inspected.

Sources

Books and journals
Brodie, Croom, Davies, , English Prisons, (2002)
Joy, Ron, Dartmoor Prison, a complete illustrated history (2 volumes), (2002)
Stanbrook, E, Dartmoor's War Prison & Church 1805-1817, (2002)

Other
Historic England Archive Report HMP Dartmoor - Building File No. 92318

End of official list entry

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