Telescopic Aildade
notes: label: Description
content: This alidade has an inverting telescope, and a vertical arc that is silvered, graduated to 20 minutes, and read by vernier to single minutes. The pedestal is painted maroon. The base, also maroon, has floral decorations at either end, a circular level vial, and a beveled edge with an 18-inch scale that is divided to fiftieths of an inch. The U. S. Geological Survey transferred it to the Smithsonian in 1907, describing it as a "preliminary type" of alidade devised for the Survey about 1890.
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: U.S. Geological Survey
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.247912
label: catalog number
content: 247912
label: accession number
content: 47736
objectType: label: Object Name
content: Alidade (Telescopic)
physicalDescription: label: Measurements
content: base: 18 1/2 in; 46.99 cm
label: Measurements
content: telescope: 11 in; 27.94 cm
label: Measurements
content: overall: 8 1/8 in x 18 5/8 in x 3 3/4 in; 20.6375 cm x 47.3075 cm x 9.525 cm