This is an aluminum compass with brass sights. The raised rim and beveled outer ring are graduated every degree, numbered every 10 degrees in
quadrants from north and south, and adjustable for variation. The western half of the face is graduated to degrees, and equipped with a pendulum clinometer pivoted at the center. There is a circular level vial at NE. The four beveled edges of the plate are graduated, one to inches and tenths, one to inches and eighths, and two as protractors. The back of the plate has a diagram
showing the arrangement of township numbering. Keuffel & Esser noted that they had made many instruments of this sort for the United States Forest Service. The serial number suggests that this example was made around 1916.
Ref: Keuffel & Esser, Catalogue (New York, 1927), p. 424.