graphometer
Date1675-1725
Inventory NumberDW0666
ClassificationGraphometer
Subject
Maker
French
Cultural Region
Dimensions12 x 27 x 10 cm (4 3/4 x 10 5/8 x 3 15/16 in.)
travelling case: 10 x 54 x 19 cm (3 15/16 x 21 1/4 x 7 1/2 in.)
travelling case: 10 x 54 x 19 cm (3 15/16 x 21 1/4 x 7 1/2 in.)
Material
Accessoriestravelling case
DescriptionThe base of the instrument is also a compass, though the dial has no markings on it. This instrument could thus be used as a protractor. The ball-and-socket joint to to fix the instrument on a pole can be completely removed. Sighting vanes can be attached to the instrument so it can become a graphometer. Openings are cut in the index arm of the instrument in order to add a plumb line for leveling purposes. The graduated quadrant is 0-90° marked every 30 minutes, and the way it was designed one need to multiply by two the measured angle to get the real angle.
The most interesting aspect of this instrument is the rugged leather traveling case that comes with it, suitable for a pack horse. This surveying ensemble was not one of those shiny objects found in a prince's collection, but a genuine field instrument.
The most interesting aspect of this instrument is the rugged leather traveling case that comes with it, suitable for a pack horse. This surveying ensemble was not one of those shiny objects found in a prince's collection, but a genuine field instrument.
In Collection(s)
Signedunsigned
Curatorial RemarksThough unsigned, it is French in style and perhaps could be attributed to Nicolas Bion.
FunctionThe graphometer is another kind of surveying instrument used for measuring angles in the horizontal as well as the vertical positions. It was invented by Philippe Danfrie at the end of the sixteenth century. Similar in use to surveying quadrants.
ProvenanceDavid Wheatland purchased from an auction in Berne, Switzerland, July 2, 1958, via Ernst Weil (#3419).
Michael Butterfield
Date: 1675-1715
Accessories: leather case stamped with fleur-de-lys
Object number: DW0663
Benjamin Martin
Date: 1738-1777
Accessories: brass cover; ball-and-socket mount (DW0511c); tripod (DW0511b).
Object number: DW0511a
Thomas Whitney
Date: circa 1817
Accessories: wooden case with key.
Object number: 5207
William Cary
Date: 1790-1820
Accessories: original mahogany box (lid warped with cracks in two places)
Object number: DW0281
E. & G. W. Blunt
Date: 1844-1857
Accessories: handwritten tables and charts; carrying case; ball-and-socket joint
Object number: 5187
J. Pool & Company
Date: circa 1850
Accessories: carrying case
Object number: 5200