Telescope
name: label: maker
content: Ramsden, Jesse
notes: label: Description
content: A telescope on an equatorial mount allows an astronomer to follow a star as it moves across the sky (or, rather, as the earth rotates below it). Several British and European forms were introduced in the latter decades of the 18th century. This one was designed and made by Jesse Ramsden.
label: Description
content: Ramsden’s Universal Equatorial instruments were expensive, and appreciated by people of means, We do not know who owned this example originally. But we do know that Thomas Jefferson had an instrument of this sort.
label: Description
content: The telescope is 16.25 inches long. The achromatic objective has an aperture of 2.5 inches. The eyepiece is missing. There is a graduated circle for right ascension and another for declination, as well as a mechanism for adjusting the instrument for use at any latitude. The horizontal limb is marked “Ramsden London.”
label: Description
content: Ref: <i>Description of a New Universal Equatoreal, Made by Mr. J. Ramsden, with the Method of Adjusting in for Observation</i> (London, 1773).
label: Description
content: <i>Description of the Universal Equatoreal, and of the New Refraction Apparatus, Much Improved by Mr. Ramsden</i> (London, 1791).
label: Description
content: Anita McConnell, <i>Jesse Ramsden(1735-1800). London’s Leading Scientific Instrument Maker</i> (Aldershot, 2007).
label: Description
content: Allan Chapman, “Jesse Ramsden” in <i>Oxford Dictionary of National Biography</i>.
label: Location
content: Currently not on view
place: label: place made
content: United Kingdom: England, London
topic: label: Subject
content: Astronomy
setName: label: See more items in
content: Medicine and Science: Physical Sciences
label: See more items in
content: Astronomy
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content: Science & Mathematics
creditLine: label: Credit Line
content: Perkin Elmer Corporation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.330487
label: accession number
content: 293727
label: catalog number
content: 330487
objectType: label: Object Name
content: telescope, refracting
label: Object Name
content: telescope
physicalDescription: label: Physical Description
content: brass (overall material)
label: Measurements
content: overall: 29 in x 15 3/4 in x 15 1/2 in; 73.66 cm x 40.005 cm x 39.37 cm
label: Measurements
content: overall: 28 1/2 in x 13 3/4 in x 15 1/2 in; 72.39 cm x 34.925 cm x 39.37 cm