Surveyor's Vernier Compass
date: label: date made
content: 1891-1906
name: label: maker
content: Mahn, Herman
notes: label: Description
content: This surveyor's compass marked "Mahn & Co. St. Louis, Mo." dates from the period 1891-1906 when Herman Mahn was trading as such. It has a variation arc on the south arm that extends 24 degrees either way. The vernier is moved by a tangent screw on the south arm, and reads to 2 minutes. An outkeeper is on the south arm, and two level vials are on the north arm.
label: Location
content: Currently not on view
place: label: place made
content: United States: Missouri, St. Louis
setName: label: See more items in
content: Medicine and Science: Physical Sciences
label: See more items in
content: Surveying and Geodesy
label: See more items in
content: Measuring & Mapping
creditLine: label: Credit Line
content: University of Missouri at Columbia.
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.333650
label: catalog number
content: 333650
label: accession number
content: 300659
objectType: label: Object Name
content: Surveyor's Compass
physicalDescription: label: Measurements
content: overall length: 15 1/2 in; 39.37 cm
label: Measurements
content: needle: 5 1/8 in; 13.0175 cm
label: Measurements
content: overall in case: 4 7/8 in x 16 1/2 in x 7 5/8 in; 12.3825 cm x 41.91 cm x 19.3675 cm