© John Talbot. No images may be copied, downloaded or reproduced without prior written permission.

Explanation of Types

Type Description Examples
Flush Bracket These are rectangular metal plates affixed to triangulation pillars, walls, buildings etc. If they are not affixed to a triangulation pillar they are often referred to as Non-Pillar Flush Brackets (NPFB). They are about 6" x 3" in size and the location of most of them is known through Ordnance Survey (OS) records. Each Flush Bracket (FB) has a unique serial number which makes them highly 'collectable' and there are several numbering types.  
  One to four figure number
The earliest FBs you can find and date from 1912-1921. Numbered from 1-3000. A few can be found on triangulation pillars.
Introduced in the 1920s these are found on pillars and as NPFBs. There are two sub-types, S below the number and S left of the number.
First appeared in 1936. Unlike S-series brackets numbers below 1000 do not have leading zeroes. Used extensively in Scotland and never found on triangulation pillars.
Just sixteen brackets used in London in the early 1930s.
  Five figure number
These are effectively S-series brackets above S9999 where they ran out of room for the S (S-below was discontinued as the S interfered with the measuring equipment).
Projecting Bracket An early type of metal bracket used for a short time before the introduction of flush brackets. They are all the same and have no unique attributes. Reading, Greyfriar's Church
OSBM Bolt Used alongside the G-series of flush brackets these are placed where there wasn't a convenient building or wall to provide a vertical surface on which to affix a flush bracket. They are domed metal bolts about 1" (50-60mm) in diameter fixed to horizontal surfaces engraved with OSBM and the benchmark symbol. Caban Coch Dam
Cut Bench Mark By far the most common type. Used and made from the 1800s to around 20 years ago. You won't have to walk (or drive) very far in any village, town or city in Britain before you spot one of these. Chiseled into stone, brick or wood on all sorts of vertical structures. A familiar horizontal levelling line with a three line arrow pointing towards it (usually upwards). Each one is unique depending on the mason who cut it, some are plain, some decorated. Some roughly cut, some exquisitely cut with high accuracy. Some small, some huge. Wallingford, 60 High Street
Cut Bench Mark with Bolt Old and rare these have a metal bolt screwed either alongside the horizontal cut of a cut bench mark or at the point of the cut arrowhead. Usually has what appears as a screwhead horizontal in the head of the bolt. These are highly prized by benchmarkers. Dorchester Abbey
Rivet Usually found on horizontal surfaces these are cut marks with a small metal domed brass rivet at the apex of the cut arrowhead marks. Swyncombe, Icknield Field
Pivot Fairly rare these are used on horizontal surfaces such as soft sandstone, where the insertion of a rivet would break away the stone. They consist of a small hole or depression cut to take a pivot, a steel ball bearing of 5/8" diameter (16mm). In use, the pivot is placed in the depression and the levelling staff held on top of the pivot. Sutton Bridge
Fundamental Bench Mark These are the key to the whole levelling of the UK. Granite blocks with large domed metal caps. Just like an iceberg this is just the tip of a fairly extensive underground structure. Highly accurate height stations still used today as the baseline to levelling. Conwy
Triangulation Pillar Familiar to anyone who walks in the British countryside, these can often (but not always) be found at hilltops. Most have a flush bracket affixed to one side. Huntingland

Cut Bench Mark with Bolt

Abergele, Gwrych Castle, Entrance Tower
Alnwick, 1 Lisburn Street
Alnwick, 11 Narrowgate
Alnwick, Lion Bridge
Alnwick, Market Hall
Alnwick, Pottergate Tower
Alnwick, St Michael's Church
Alnwick, St Paul's Church
Alnwick, Town Hall
Appleby, St Michael's Church
Bagillt, Church of St Mary and St Peter
Benson, St Helen's Church
Bessels Leigh, The Greyhound
Brecon Cathedral
Caernarfon, St Mary's Church
Cambridge, Great Bridge
Chester, Eastgate
Chipping Norton, St Mary's Church
Covehithe, St Andrew's Church
Cromer, St Peter & St Paul's Church (bolt)
Dingwall, Highland Theological College
Dorchester, Abbey Church
Edinburgh, National Monument of Scotland
Edinburgh, Nelson Monument
Edinburgh, Old College
Edinburgh, Tron Church
Edisford Bridge
Ely, Holy Trinity Cathedral
Greenwich, ORNC - King Charles' Quarter
Greenwich, ORNC - King William's Quarter
Greenwich, ORNC - Queen Mary's Quarter
Greenwich, St. Alfege's Church
Hay-on-Wye, St Mary's Church
Holywell, St James' Church
King's Lynn, Greyfriars Tower
King's Lynn, St Margaret's Church
Kingston Bagpuize, St John the Baptist Church
Leicester, County Gaol
Leicester, Holy Cross Centre
Llanddulas, Hen Wrych Lodge
Llanddulas, River Dulas Bridge
Longworth, St Mary's Church
Nottingham, St. Mary's Church
Nottingham, St. Peter's Church
Nuffield, Holy Trinity Church
Oswestry, St Oswald's Church
Oxford, County Hall
Oxford, St Thomas the Martyr's Church
Oxford, St. Mary Magdalen's Church
Oxford, St. Michael's Church
Paddington St James, Sussex Gardens
Plymouth, 7 Castle Dyke Lane
Plymouth, North Road Railway Bridge
Plymouth, Royal Citadel, West Sally Port
Plymouth, St Peter's Church
Poole, St James' Church
Reading, St Mary's Church
Rhuddlan, Rhuddlan Bridge
Rhuddlan, St Mary's Church (SW)
Salisbury, St Mary's Cathedral
Salisbury, St Thomas's Church
Southampton, South Gate
Southampton, St Michael's Church
Southampton, West Gate
St Ives, St Ia's Church
Warborough, St Laurence's Church
Warwick, 24 Mill Street
Warwick, St. Mary's Church
Warwick, St. Nicholas's Church
West Runton, Holy Trinity Church
Westminster, Lower Grosvenor Place
Wooler, St Ninian's RC Church
York, York Minster


All the bench marks I have logged. See my profile on the Bench Mark Database.

Show Help

By Type

Explanation of Types
Flush Bracket(188)
Projecting Bracket(6)
OSBM Bolt(10)
Cut Bench Mark(1285)
Cut Bench Mark with Bolt(73)
Fundamental Benchmark(8)
Triangulation Pillar(93)
 Show All(2270)

By Year

2018 (153)
2017 (253)
2016 (386)
2015 (409)
2014 (256)
2013 (120)
2012 (21)
2011 (78)
2010 (54)
2009 (84)
2008 (79)
2007 (248)
2006 (16)
2005 (39)
2004 (72)
2003 (2)