Object Details
- Troughton and Simms
- Description
- The Proprietors of the Locks & Canals in Lowell, Mass., used this theodolite to lay out the canals that provided transportation and power for the textile mills in that city. It was probably made soon after 1826, when John Troughton took William Simms into partnership and began trading as Troughton & Simms. Exceot for its lack of magnifiers, it is identical to the theodolite described in F. W. Simms, A Treatise on the Principal Mathematical Instruments (London, 1836). The horizontal circle and vertical arc are silvered, and read by verniers to 20 seconds.
- The scale for "Diff. of Hypo. & Base" on the back of the vertical arc is used to correlate the angle of elevation or depression with horizontal distances when surveying sloping ground. The inscription reads "Troughton & Simms LONDON."
- Credit Line
- Proprietors of the Locks and Canals on the Merrimack River
- ID Number
- PH.314774
- accession number
- 211155
- catalog number
- 314774
- Object Name
- theodolite
- Measurements
- overall: 13 1/2 in; 34.29 cm
- horizontal circle: 7 in; 17.78 cm
- needle: 3 in; 7.62 cm
- telescope: 13 1/4 in; 33.655 cm
- hanging level: 5 1/4 in; 13.335 cm
- place made
- United Kingdom: England, London
- See more items in
- Medicine and Science: Physical Sciences
- Surveying and Geodesy
- Measuring & Mapping
- National Museum of American History
- Record ID
- nmah_747873
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746a5-898c-704b-e053-15f76fa0b4fa
