T. Jones Geodetic Transit

Description
This transit may be one of the earliest extant instruments of the U. S. Coast Survey. It is marked "Thos Jones Liverpool" and “U.S.C.S. No. 12." Thomas Jones, who worked as an instrument maker and dealer in Liverpool during the period 1816–1831 should not be confused with the Thomas Jones of London who made the transit theodolite for the Coast Survey, which is also in the collections.
The vertical circle attached to one end of the slightly conical horizontal axis is graduated to 15 minutes, and read by opposite verniers to single minutes. At the other end of the axis is a wooden lamp holder. The lattice work cast iron base has 3 leveling feet.
Ref: Gloria Clifton, Directory of British Scientific Instrument Makers 1550–1851 (London, 1995), p. 154.
Location
Currently not on view
Object Name
geodetic transit
maker
Jones, Thomas
Measurements
telescope: 20 in; 50.8 cm
vertical circle: 6 in; 15.24 cm
place made
United Kingdom: England, Liverpool
ID Number
PH*316521
accession number
225703
catalog number
316521
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Surveying and Geodesy
Data Source
National Museum of American History, Kenneth E. Behring Center

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