By Brook Culvert

Summary

A small bridge or culvert over the By (or Box) Brook about 250m south-west of Box Mill, designed by Brunel and made of Bath stone in around 1840. With minor later alterations to the north face.

Reasons for Designation

By Brook Culvert, Box, is listed at Grade II for the following principal reasons:

Architectural interest:

* as an early example of a railway structure dating from the pioneering phase in national railway development;
* an example of a culvert or underbridge that survives unusually well from the earliest phase of the Great Western Railway;
* an architectural treatment on structures of this type is unusual and, in this case, the impressive rusticated voussoirs on the south side with raked abutments and coping remain unaltered since construction.

Historic interest:

* it is constructed to a design by Isambard Kingdom Brunel who is widely perceived as one of the most important transport engineers and architects of the C19.

History

Great Western Railway

The Great Western Railway was authorised by an Act of Parliament in 1835 to construct a line from London to Bristol. At 118 miles this was slightly longer that the other major trunk railway of its time, the London and Birmingham (112 miles) and considerably longer than other pioneering lines. Construction of the line began in 1836, using a variety of contractors and some direct labour. The first section to be completed, from London to Maidenhead Riverside (Taplow), opened in 1838, and thereafter openings followed in eight phases culminating in the completion of the whole route in 1841.

The engineering of the railway was entrusted in 1833 to Isambard Kingdom Brunel (1806-1859), who was already known for his engineering projects in Bristol. More than any other railways engineer of his time he took sole responsibility for every aspect of the engineering design, from surveying the line to the detailing of buildings and structures. He sought to achieve as level a route as possible and, working from first principles, he persuaded the Directors of the GWR to adopt a broad gauge of 7ft 0¼ in rather than the standard (4ft 8½ in) gauge in use on other lines. A two track broad gauge line was 30ft wide, and this determined the span of the overbridges and other structures. Except for larger bridges such as Maidenhead Bridge, the majority of Brunel’s masonry bridges did not need to be as innovative as his works in timber and iron, and his structures followed the typical architectural idioms of his time, but they were all beautifully detailed and built and together they formed integral parts of a consistently-designed pioneering railway.

Although he left no written statement concerning his design concept for the line, it can be inferred from its design and from the way it was described when opened that part of his vision was a line engineered according picturesque principles. This influenced his selection of the route and the design of structures along it. For reasons of cost, but also because it helped blend the railway to the landscape, he used local materials for bridges and other structures, ranging from stock brick at the London end of the line, to red brick, Bath stone east of Bath and Blue Lias stone west of Bath. This intentional variety was remarked on by contemporaries, for instance in J C Bourne, ‘The History and Description of the Great Western Railway’ (1846).

Surviving contract drawings for bridges and other structures on this section of the line carry the signature of I K Brunel, reflecting his involvement with every aspect of the project. The Resident Engineer was G E Frere (1807-1887), assisted by G T Clark (1809-1898) and Michael Lane (1802-1868), but their individual contributions have not been identified.

By Brook Culvert

By (or Box) Brook Culvert was built in around 1840 under Contract 15B on the Chippenham to Bath section of the route, which opened on 30 June 1841. It is one of two such structures (the other By Brook Bridge, Grade II, LE: 1410949) that cross the brook. By Brook formerly powered Box Mill, approximately 250m to the north-east, a corn mill that ceased operation in the mid-C20 and was converted to Real World Studios in the 1980s. A contract drawing for ‘Culvert of Brook near Box Mill’ survives of the structure. The elevations on the drawing reflect those of the culvert. It was designed by Brunel to carry the line, elevated on an embankment, and a footpath at lower level on the south (Down) side over the By Brook. The south face is impressively architectural for a structure of this scale, probably due to its position in the landscape as visible from the village across green open space. Unusually for a railway bridge, this face is unaltered. The more plain north (Up) elevation has had some alterations.

Details

MATERIALS: Bath stone ashlar with rubble Bath stone soffit, and patching in engineering brick to the north face.

DESCRIPTION: the south face of the culvert has a horseshoe arch springing from water level, with bold voussoirs spraying from it and an emphatic keystone. There are raked abutments to each side and plain coping with no parapet. The north face is plainer, with no voussoirs. The east (low mileage) abutment and part of the arch ring of this face have been refaced in engineering brick and two metal pipes have been inserted above the arch. A footpath crosses above the south end of the culvert.

The structure crosses the By (or Box) Brook between ST8234368779 (South) and ST8235768821 (North).

Sources

Books and journals
MacDermot, E T, History of the Great Western Railway 1833 to 1863, (1964)
Brindle, S, Cruickshank, D, Brunel: The Man Who Built the World, (2005)
Bourne, J C, The History and Description of the Great Western Railway, (1846)
Cross-Rudkin, P, Chrimes, M, EDS, Biographical Dictionary of Civil Engineers Volume 2: 1830–1890, (2008)
Pugsley, A, The Works of Isambard Kingdom Brunel, (1976)
Vaughan, A, A Pictorial Record of Great Western Architecture, (1977)
Swift, A, The Ringing Grooves of Change, Brunel and The Coming Of The Railway To Bath with The Story of Box Tunnel, (2006), 284

Other
Alan Baxter & Associates, The History and Significance of the Great Western Main Line, 2012
Kinchin-Smith, R, Crossrail Technical Assessment of Historic Railway Bridges, 2005
Network Rail National Records Centre, Roll Number 13176, Culvert of Brook near Box Mill. Contract N15B Drawing N8.

End of official list entry

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