Simpson Surveyor's Vernier Compass

This surveyor's vernier compass has an unusual and ornate face decorated with Masonic symbols. The variation arc on the north arm extends 10 degrees either way; the vernier is moved by rack and pinion, and reads to 10 minutes. A level vial is on the south arm. The "J. SIMPSON BARDSTOWN KY" inscription refers to Jonathan Simpson (1787-1863) who was was working in Kentucky by 1820, and who advertised in the Bardstown newspaper, The Republican, on October 3, 1844: "I shall keep on hand a constant supply of SILVERWORK of my own manufacture-warranted to be as good as any manufactured in the United States, and at the Cincinnati prices. My necessities compel me to labour as much as ever I did. I have a few Surveying instruments on hand, which I will sell very low."

National Museum of American History - Plain Compass