Object Details
- Phelps & Gurley
- Description
- This is an example of instrument makers feeling their way towards a good design, but not quite getting it right. It is marked "Phelps & Gurley" and "Troy, N.Y." and dates from the period 1845-1851 when Jonas Phelps and William Gurley were in business together. Several elements of its design originated with Oscar Hanks, the mathematical instrument maker with whom Phelps and Gurley both apprenticed. W. & L. E. Gurley made a similar instrument that they called a Vernier Transit Compass.
- The variation arc at the south side of the compass extends 20 degrees either way; the vernier reads to 2 minutes. There are level vials at North and West. The small vertical circle is read by vernier to 10 minutes.
- William H. Skerritt, Catalog of the Charles E. Smart Collection of Antique Surveying Instruments (Troy, N.Y., 1996), p. 29.
- Location
- Currently not on view
- Credit Line
- Leland C. Ball
- ID Number
- PH.315412
- accession number
- 170660
- catalog number
- 315412
- Object Name
- transit instrument
- surveyor's transit
- Measurements
- overall: 7 in; 17.78 cm
- needle: 5 in; 12.7 cm
- vertical circle: 3 1/2 in; 8.89 cm
- telescope: 9 3/4 in; 24.765 cm
- overall: 11 1/8 in x 8 3/4 in x 9 3/4 in; 28.2575 cm x 22.225 cm x 24.765 cm
- place made
- United States: New York, Troy
- Related Publication
- Skerritt, William H.. Catalog of the Charles E. Smart Collection of Antique Surveying Instruments
- See more items in
- Medicine and Science: Physical Sciences
- Surveying and Geodesy
- Measuring & Mapping
- National Museum of American History
- Record ID
- nmah_745970
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746a5-9340-704b-e053-15f76fa0b4fa
