Ordnance Survey's Levelling of Great Britain

[2GL Abstract] [2GL Transcription]

What's new for November 2004 (See Dec 2004 and 2005)

Site can now be accessed at www.trigtools.co.uk !

The Second Geodetic Levelling Abstract (Go)

• Has now been totally transcribed(?) to electronic format.
• But the location of many Benchmarks still needs to be found and checked out.
  • Nearly have a plotting tool ready based on old-maps.co.uk!
• New Progress Map and Statistics Page as well as detailed and Abstract Index(with stats)
• Graeme has been steadily updating NPFB_MSN.xls (photo index of OSBM msn group) which is helping to keep the Transcription uptodate. (comparison)

Interactive Mapping (Go)

• Now displays Roads, Motorways, Railways, Rivers and Built Up areas. (example)
• Trigs and Secondary blocks can be shown (example)
• Can center the map on any Landranger or Explorer Sheet (example)
• Map is clickable and can copy and paste the GR of the mouse pointer (try it here)
  • Click on the map so that the boxes with update with the current GR, clicking again will 'fix' the location.

Location Search (NEW)

• Search by GR - find results from many different datasets,
  • including Trigs, Wall FB's, Passive Stations and FBM's.
  • Many datasets like Geocaches, Walks and Fords have been added, making it a general location based search engine for many points of interest.
• Search by FB number - find a particular number wherever its located
• Search by name - find a particular number wherever its located

• as a spinoff of this now have a more accurate combined list of all FB numbers!
• it is also helping to identify errors in various databases...
• See also statistics and datasets/Sources used in its compilation

Documents and Maps

• Progress diagrams from OS Annual Reports '54-67 have been located showing Secondary lines post 3GL.
• Maps of 3GL in Scotland and some for England and Wales have been made available.
• Few other files on FBM's and London levelling are also here

First Geodetic Levelling (Go)

• A large scale plotting of this is nearly finished (of just main points on each line)
• the transcription is soon to be available online

London FB's (Go)

• some lists of FB's in the London area have been located
• See map of London levelling here

• Add this link to your favorites (IE4+): Co-ordinate Converter
  Select a GR or Postcode in ANY webpage and click on the favorite and you will be taken here with the coordinate filled!
• Links to many more websites (mainly when using OS Grid refs)
• Will identify the Pre and Post 1974 Counties of the given location.
• Will identify the Landranger and Explorer Sheets for the given location
• Calculates OS Map Tile References (eg SP08SW86)
• other minor cleanups and bug fixes

TrigTools at TrigpointingUK.com (Go) - Triangluation

• Fun photographic Album is progressing nicely
• a photo indentifying competition is in the pipeline
• Download Your Logs as a CSV: useful for backing up your logs

Other Areas of the site (not recently updated)

• Irish Trigpoints - find trigpoints in Ireland
• Placename Gazetteer - search for places in the UK
• FBM list - list of all known (and extinct) Fundamental Benchmarks as well as Tide Guages
• Timeline - events in OS history (some minor updates in light of recent data)
• Slides and Files from National Archives at Kew (Index)