Ordnance Survey – Great Britain's national mapping agency
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We hold information literature on a number of technical topics.
- Grid north, magnetic north and true north
- Records of Ordnance Survey held at the Public Records Office
- Numbering of 6" to 1 mile and 1:25 000 scale County Series maps
- Abbreviations used on Ordnance Survey maps
- Professional papers
- Calculating the distance between two points using their National Grid References
- Glossary of terms
- Historic Draftsmans, Plan and Field Examiners instructions
- Surveying and mapping