Monument at South-eastern End of General Roy's Survey Base
MONUMENT AT SOUTH-EASTERN END OF GENERAL ROY'S SURVEY BASE, ROY GROVE
Listed on the National Heritage List for England. Search over 400,000 listed places
Overview
- Heritage Category:
- Listed Building
- Grade:
- II
- List Entry Number:
- 1263302
- Date first listed:
- 25-May-1983
- List Entry Name:
- Monument at South-eastern End of General Roy's Survey Base
- Statutory Address:
- MONUMENT AT SOUTH-EASTERN END OF GENERAL ROY'S SURVEY BASE, ROY GROVE
Location
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Images of England Project
- Date:
- 1999-10-19
- Reference:
- IOE01/00810/08
- Rights:
- © Mr Barry Akid. Source: Historic England Archive
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Discover moreOfficial list entry
- Heritage Category:
- Listed Building
- Grade:
- II
- List Entry Number:
- 1263302
- Date first listed:
- 25-May-1983
- List Entry Name:
- Monument at South-eastern End of General Roy's Survey Base
- Statutory Address 1:
- MONUMENT AT SOUTH-EASTERN END OF GENERAL ROY'S SURVEY BASE, ROY GROVE
The scope of legal protection for listed buildings
This List entry helps identify the building designated at this address for its special architectural or historic interest.
Unless the List entry states otherwise, it includes both the structure itself and any object or structure fixed to it (whether inside or outside) as well as any object or structure within the curtilage of the building.
For these purposes, to be included within the curtilage of the building, the object or structure must have formed part of the land since before 1st July 1948.
The scope of legal protection for listed buildings
This List entry helps identify the building designated at this address for its special architectural or historic interest.
Unless the List entry states otherwise, it includes both the structure itself and any object or structure fixed to it (whether inside or outside) as well as any object or structure within the curtilage of the building.
For these purposes, to be included within the curtilage of the building, the object or structure must have formed part of the land since before 1st July 1948.
Location
- Statutory Address:
- MONUMENT AT SOUTH-EASTERN END OF GENERAL ROY'S SURVEY BASE, ROY GROVE
The building or site itself may lie within the boundary of more than one authority.
- County:
- Greater London Authority
- District:
- Richmond upon Thames (London Borough)
- Parish:
- Non Civil Parish
- National Grid Reference:
- TQ1372070985
Details
TQ 17 SW
22/3/3
25/5/83
ROY GROVE, Hampton
Monument at south-eastern end of General Roy's survey base
II
Cast-iron cannon monument, installed 1791 to mark the south-eastern end of the baseline measured by General Roy in 1784 across Hounslow Heath, from King's Arbour to Hampton Poor House, which is now taken to be the origin of the Ordnance Survey. Roy originally marked his line by wooden posts, but in 1791 two guns were selected at Woolwich 'from amongst those which had been condemned as unfit for the public service'. The cannon is some nine feet long, the lower six feet of which are buried in the ground. Near the cannon is a plaque which reads as follows:
'This tablet was affixed in 1926 to commemorate the 200th anniversary of the birth of Major General William Roy FRS, born 4th May 1726 - died 1st July 1790. He conceived the idea of carrying out the triangulation of this country and of constructing a complete and accurate map and thereby laid the foundation of the Ordnance Survey. This gun marks the SE terminal of the base which was measured in 1784, under the supervision of General Roy, as part of the operations for determining the relative positions of the Greenwich and Paris Observatories. This measurement was rendered possible by the munificence of HM King George III, who inspected the work on 21st August 1784. The base was measured again in 1791, by Captain Mudge, as the commencement of the principal triangulation of Great Britain. Length of base - reduced to MGL - as measured by Roy - 27404.01 feet, as measured by Mudge - 27404.24 feet, as determined by Clarke in 1858 in terms of the Ordnance Survey Standard 02 - 27406.19 feet.'
Source: Captain William Mudge and Isaac Dalby, An Account of the Operations Carried on for Accomplishing a Trigonometric Survey of England and Wales, vol. I, 1799, p.223.
The monument at the north-west end of General's Roy's baseline is listed under Northern Perimeter Road, Heathrow Airport, in the London Borough of Hillingdon.
Listing NGR: TQ1372070985
Legacy
The contents of this record have been generated from a legacy data system.
- Legacy System number:
- 432627
- Legacy System:
- LBS
Sources
Books and journals
Mudge, , Dalby, , An Account of the Operations Carried on for Accomplishing a Trigonometric Survey of England and Wales Volume I, (1799), 223
Legal
This building is listed under the Planning (Listed Buildings and Conservation Areas) Act 1990 as amended for its special architectural or historic interest.
Map
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