Geodetic Transit
notes: label: Description
content: This transit marked "USC&GS No. 18" was designed by E. G. Fischer, chief mechanician of the U. S. Coast and Geodetic Survey. It is one of two identical instruments that were built in the Survey's instrument shop in 1888–1889. They were said to be "the most complete and best constructed transits the Survey has ever had for longitude." They had about the same optical power as the transits that Troughton & Simms had made in the 1840s, but weighed substantially less. When packed in two boxes for transportation, each instrument weighed "only" about 350 pounds. John Clacey made the objective lenses, and Edward Kahler made the eyepieces.
label: Description
content: G. N. Saegmuller, who offered an apparently identical instrument for $900, termed it a "Coast Survey Transit. No. 30" and noted that the Survey used instruments of this sort "for time observations only."
label: Description
content: Ref: Edwin Smith, "A Description of Two New Portable Transit Instruments for Longitude Work," <i>Report of the Superintendent of the U.S. Coast and Geodetic Survey for 1889</i> (Washington, D.C., 1890), Appendix No. 9.
label: Description
content: G. N. Saegmuller, <i>Descriptive Price–List of First–Class Engineering & Astronomical Instruments</i> (Washington, D.C., 1903), p. 75.
label: Location
content: Currently not on view
place: label: place made
content: United States: District of Columbia
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: Saegmuller, George N.. Descriptive Price-List of First-Class Engineering & Astronomical Instruments
label: Related Publication
content: U.S. Coast and Geodetic Survey. Report of the Superintendent of the U.S. Coast and Geodetic Survey
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.316661.01
label: accession number
content: 226636
label: catalog number
content: 316661
objectType: label: Object Name
content: geodetic transit
physicalDescription: label: Measurements
content: aperture: 3 1/2 in; 8.89 cm
label: Measurements
content: telescope: 39 1/2 in; 100.33 cm