Surveyor's Cross
notes: label: Description
content: A surveyor’s cross is a simple instrument used to lay out straight lines and lines at right angles to one another. There are two forms. The open form has four arms set at right angles to one another, with an open sight at each end. The closed form is solid, with four slits at right angles to one another; this seems to have been introduced around 1803 by William Jones, an instrument maker in London.
label: Description
content: This example, closed and cylindrical, has a silver band graduated to degrees, and read by vernier to 2 minutes. There are two slits on the lower part of the cylinder, and four on the upper part. There is a magnetic compass on top. It probably belonged to Llewellyn N. Edwards (1874-1952), a structural engineer.
label: Description
content: Ref: <i>The Cyclopaedia; or, Universal Dictionary of Arts, Sciences, and Literature</i>, ed. Abraham Rees (London, 1819), vol. x, art. "Cross, in Surveying."
label: Location
content: Currently not on view
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: Estate of Carolyn H. Edwards
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.333799
label: catalog number
content: 333799
label: accession number
content: 296611
objectType: label: Object Name
content: Surveyor's Cross
physicalDescription: label: Measurements
content: overall: 6 3/4 in x 2 3/4 in; 17.145 cm x 6.985 cm
label: Measurements
content: overall: 3 7/16 in x 7 3/4 in x 3 3/4 in; 8.73125 cm x 19.685 cm x 9.525 cm