Brass quadrant by Peter and John Dollond of 18-inch radius with optical sights on a tripod

Made:
1780-1820
maker:
John Dollond
Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London. Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Portable brass quadrant of 18-inch radius with optical sights on a tripod stand by Dollond, London.
Science Museum Group Collection
© The Board of Trustees of the Science Museum, London

Brass quadrant of 18-inch radius with optical sights on a tripod stand. Made by Peter and John Dollond, St Paul’s churchyard, London, and issued by the British Admiralty for surveying work in Lower Canada.

This London-made quadrant was supplied by the British Admiralty around 1800 for surveys in Lower Canada, present-day Quebec. It is associated with Lt.-Colonel Joseph Bouchette (1774-1841), the Surveyor-General of Lower Canada.

Quadrants are used to measure the altitude of celestial objects and the angular distance between them. They were used by surveyors to determine precisely their longitude and latitude.

Much of the territory in Lower Canada was relatively unknown to the British. They produced maps, charts and topographical sketches of the region as they sought to defend their interests against indigenous peoples, and against the French and Americans.

Details

Category:
Astronomy
Object Number:
1911-214/1
type:
optical quadrant - measuring device
taxonomy:
  • furnishing and equipment
  • measuring device - instrument
credit:
British Admiralty (Hydrographic Department)