Surveyor's Vernier Compass
name: label: maker
content: W. & L. E. Gurley
notes: label: Description
content: The rim of this compass is graduated to 30 minutes. The variation arc on the south arm extends 20 degrees either way, and is read by folded vernier to 2 minutes. Two level vials are on the north arm, and an outkeeper is on the south arm. The side of one vertical sight is graduated to half degrees, for determining angles of elevation or depression. The machine-engraved "W. & L. E. Gurley Troy, N.Y." signature indicates a date of manufacture after 1876. The lack of serial number indicates a date before 1908.
label: Description
content: Ref: W. & L. E. Gurley, <i>A Manual of the Principal Instruments Used in American Engineering and Surveying</i> (Troy, N.Y., 1904), pp. 108-120.
label: Location
content: Currently not on view
place: label: place made
content: United States: New York, Troy
setName: label: See more items in
content: Medicine and Science: Physical Sciences
label: See more items in
content: Surveying and Geodesy
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content: Measuring & Mapping
publisher: label: Related Publication
content: W. & L. E. Gurley. Manual of the Prinicipal Instruments Used in American Engineering and Surveying; 37th Edition
creditLine: label: Credit Line
content: Columbia University
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.335209
label: catalog number
content: 335209
label: accession number
content: 317998
objectType: label: Object Name
content: Surveyor's Vernier Compass
physicalDescription: label: Measurements
content: overall length: 15 1/2 in; 39.37 cm
label: Measurements
content: needle: 6 in; 15.24 cm
label: Measurements
content: overall in case: 4 13/16 in x 16 1/2 in x 8 1/2 in; 12.22375 cm x 41.91 cm x 21.59 cm