Altitude and Azimuth Instrument
date: label: date made
content: ca 1837
name: label: maker
content: Troughton and Simms
notes: label: Description
content: This astronomical instrument belonged to Columbia College (now University), and dates from around 1837. The horizontal and vertical circles are silvered, graduated to 10 minutes, and read by verniers to 10 sec. The inscription reads "Troughton & Simms, London."
label: Description
content: Ref: Frederick W. Simms, <i>A Treatise on the Principal Mathematical Instruments Employed in Surveying, Levelling, & Astronomy</i> (Baltimore, 1844), pp. 89–109, describes a similar instrument with two vertical circles.
label: Location
content: Currently not on view
place: label: place made
content: United Kingdom: England, London
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
publisher: label: Related Publication
content: Simms, Frederick W.. Treatise on the Principal Mathematical Instruments Employed in Surveying, Levelling, & Astronomy; 5th Edition
creditLine: label: Credit Line
content: Columbia University. Department of Physics
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.323689
label: catalog number
content: 323689
label: accession number
content: 249200
objectType: label: Object Name
content: altitude and azimuth instrument
physicalDescription: label: Measurements
content: overall: 21 in; 53.34 cm
label: Measurements
content: horizontal circle: 11 1/2 in; 29.21 cm
label: Measurements
content: vertical circle: 9 in; 22.86 cm
label: Measurements
content: telescope: 20 in; 50.8 cm
label: Measurements
content: overall: 22 in x 20 in x 15 in; 55.88 cm x 50.8 cm x 38.1 cm