Potts Surveyor's Vernier Compass

William Lukens Potts (1771-1854) worked with Benjamin Rittenhouse in the years 1796-1798, making plain and vernier compasses. In 1800, now in business on his own, he advertised "surveying instruments of all kinds, and Rittenhouse' Circumferentors, with each a nounes and spirit level compleat." "Nounes" here refers to a nonius, a term sometimes used in place of vernier.
This example is marked "W.L. POTTS Bucks Penna." It was made between 1807, when Potts bought land in Bucks County, Pa., and 1817, when he moved to Philadelphia. It has a variation arc on the south arm that extends 15 degrees either way; the "folded" vernier is moved by rack and pinion, and reads to 5 minutes. There is a spirit level on the north arm. A copy of Thomas Whitney's 1814 discussion of "The Variation of the Compass" is pasted into the inside cover of the wooden box.
Currently not on view
Object Name
compass (surveyor's vernier)
date made
Potts, William Lukens
overall length: 14 1/4 in; 36.195 cm
needle: 5 in; 12.7 cm
place made
United States: Pennsylvania, Bucks county
ID Number
accession number
catalog number
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
Additional Media

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.