This compass belonged to the noted American geologist, Charles Doolittle Walcott (1850-1927), and may be the one mentioned in his paper of 1888. It is made of aluminum. The raised rim is graduated to 30 minutes, and numbered every
10 degrees from north and south. The southern half of the face has a clinometer scale, extending ± 90 degrees, and graduated to 30 minutes.
Walcott had joined the U.S. Geological Survey in 1879, and became Director of that organization in 1894. In 1907 he was named Secretary of the Smithsonian Institution. One inscription on the back of the compass reads: "C. D. WALCOTT U.S. GEOLOGICAL SURVEY WASHINGTON D.C. AUGUST 1894." Another reads: "SECRETARY SMITHSONIAN INSTITUTION 1907."
Ref.: C. D. Walcott, "A Simple Method of Measuring the Thickness of Inclined Strata," Proceedings of the United States National Museum (1888): 447-448.