Pocket Compass (prismatic)
Pocket Compass (prismatic)
- Description
- This compass is similar to the one for which Charles Schmalcalder, a London instrument maker, obtained a British patent in 1812. It is designed so that a surveyor can read the card while sighting a distant object. It has a tall folding sight at north, and at south, a shorter sight with a prismatic eyepiece at its base. The floating card is colored bright green; the numbers around its edge read correctly when seen through the prismatic eyepiece.
- This example is marked "U. S. ENGINEERS" and "J. Green N. Y." The U. S. Weather Bureau transferred it to the Smithsonian in 1954. James Green was born in England in 1808, moved to the United States around 1832, and opened an instrument shop in Baltimore. He opened a second shop in New York in the early 1840s, and retired in 1885.
- Location
- Currently not on view
- Object Name
- Pocket Compass (Prismatic)
- maker
- Green, James
- place made
- United States: New York
- Measurements
- overall: 3 in; x 7.62 cm
- overall: 13/16 in x 4 in x 3 in; 2.06375 cm x 10.16 cm x 7.62 cm
- ID Number
- PH.314563
- catalog number
- 314563
- accession number
- 204612
- Credit Line
- U.S. Department of Commerce, U.S. Weather Bureau
- See more items in
- Medicine and Science: Physical Sciences
- Surveying and Geodesy
- Measuring & Mapping
- Data Source
- National Museum of American History
Nominate this object for photography.
Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.
If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.