The arms of this brass instrument have plain ends, but the hinge is decorated with a flower. One side has a double scale of chords that runs from 10 to 180; a double scale for "les Solides" that runs from 1 to 60; and a double scale for the specific weights of five metals, marked with their symbols. The outer edge of both arms has a scale that runs from 1/4 to 60 and is labeled Diamettre [sic] et Poids des Boulets. The sector is marked: Butterfield (/) AParis.
On the other side, the outer edge has a scale that runs from 1/4 to 60 and is labeled Calibre des Pieces. There are double scales of equal parts, running from 10 to 200; for "les plans," running from 10 to 60; and for inscribed regular polygons, from 12 sides to three sides. Compare to MA.321676 and 1985.0580.04.
Michael Butterfield (1635–1724) was an English instrument maker who worked in France from around 1677 until his death. He was best known for his distinctive sundials.
References: Maya Hambly, Drawing Instruments, 1580–1980 (London: Sotheby's Publications, 1988), 24, 134–135; Anthony Turner, "Sector," in Instruments of Science: An Historical Encyclopedia, ed. Robert Bud and Deborah Jean Warner (New York and London: Garland Publishing, 1998), 526–528.
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.