"Butterfield Proportion Compass C. 1700"
Proportion compass signed "Butterfield in Paris", that is to say Michael Butterfield, active in Paris around 1675 and 1724. The French proportion compass is the instrument of mathematics and engineering par excellence of the 17th and 18th centuries. This model is of beautiful design, nicely engraved. It has eight lines: equal parts, planes, polygons, weights of balls, strings, solids, weights, metals and the caliber of the pieces. Good condition of the brass and the engraving. 17.2cm closed. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato