Circumferentor
ca. 1770 – 1800
Engineers used this instrument to lay out entrenchments, fortifications, and large camps. This surveying instrument sat on a wooden tripod or staff. It contains a circular brass bar with sights and a compass in the middle.
Wood, brass, glass. L 30, H 6, Dia 22.9 cm
Valley Forge National Historical Park, VAFO 30274