Dip Circle
date: label: Date made
content: ca 1860
name: label: maker
content: Wurdemann, William W.
notes: label: Description
content: This dip circle was designed by Julius Hilgard of the U.S. Coast Survey, constructed by William Würdemann, and in use by 1860. The vertical circle is located outside the wood and glass box, silvered, graduated to 15 minutes, and read by opposite verniers with magnifiers to 30 seconds. It supports two telescopes which are used to take sights on small holes pierced through the ends of the needle. The horizontal circle is silvered, graduated to 30 minutes and read by vernier to single minutes. The inscriptions read "Wm Würdemann, Washington, D.C." and "U.S.C.S. No. 10."
label: Description
content: Ref: "Results of Magnetical Observations Made at Eastport, Maine, Between 1860 and 1864, for the United States Coast Survey," <i>Report of the Superintendent of the United States Coast Survey During the Year 1865</i>, Appendix 18.
label: Location
content: Currently not on view
place: label: Place Made
content: United States: District of Columbia, Washington
topic: label: Subject
content: Science & Scientific Instruments
setName: label: See more items in
content: Medicine and Science: Physical Sciences
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content: Science & Mathematics
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content: Measuring & Mapping
creditLine: label: Credit Line
content: U.S. Coast & Geodetic Survey
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.314633
label: catalog number
content: 314633
label: accession number
content: 208213
objectType: label: Object Name
content: dip circle
physicalDescription: label: Physical Description
content: metal (overall material)
label: Measurements
content: vertical circle: 6 1/2 in; 16.51 cm
label: Measurements
content: overall: 14 3/4 in x 12 13/16 in x 8 1/16 in; 37.465 cm x 32.54375 cm x 20.47875 cm