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Telescopic Surveyor’s Spirit Level
Catalog #: 1997.0353.01,
Accession #: 1997.0353
Currently on display
From the Smithsonian Collection
"This is one of the earliest wye levels in America. It was made by Benjamin Rittenhouse around 1785 and owned by George Gilpin, who was the chief surveyor for the Potowmack Canal Navigation Company. Although this Canal Company had been organized in 1772, the project was shelved during the Revolution. It resumed in 1785 and construction began the following year. Thomas Ellicott purchased the level at the sale of Gilpin's estate in Alexandria, Virginia, in 1813, and it remained in his family until its donation to the Smithsonian Institution in 1997. The level vial of this instrument is mounted above the telescope. In the form that would become standard in the 19th century, the level hangs below the telescope.
Ref: Silvio A. Bedini, "The Telescopic Level in Early America," Rittenhouse 11 (1997): 109-123.
--from http://americanhistory2.si.edu/surveying/object.cfm?recordnumber=748722
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Physical Description |
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Dimensions: 28" L x 6.25" W x 2.25" H (70.5 cm L x 15.6 cm W x 6cm H )
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Details |
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Locations: |
Pennsylvania, Virginia
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Credit: | Gift of Charles Ellis Ellicott III, M.D. |
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History |
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Surveyors use telescopic levels to draw level surfaces and to determine the difference in altitude between several points. In a wye (or Y) Level, the supports for the telescope are shaped like the letter Y. This means that the telescope can be easily removed and turned back to front."
--from http://americanhistory2.si.edu/surveying/type.cfm?typeid=13
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Related People, Places, and Events |
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Manufacturer
Benjamin Rittenhouse
User
George Gilpin
Gilpin, owner and user of the level, was the chief surveyor for the Potowmack Canal Navigation Company.
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