Pauline Hortense Gontard, of Cortébert, Switzerland, submitted this brass model with her patent application for an improvement in the winding mechanism in a stem winding watch or keyless watch. By the time, she applied for the patent in the United States in 1879, American watchmakers were mass producing watches and competing with European watch makers.
Stem winding watches were invented by a French clock maker in 1842 and patented in Europe in 1845. Before this time a key was necessary to wind a watch mechanism.
Patent model for William Austin Burt, new equatorial sextant, U.S. Patent 16,002 (1856). This instrument could apparently be used to take azimuths, altitude, and time with one observation, and thus enable one to easily obtain the position and bearing of a ship at sea. It was ingenious, but never found much of a market. Burt is better remembered for the solar compass that he introduced in the 1830s.
Ref: John S. Burt, They Left Their Mark. A Biography of William Austin Burt (Rancho Cordova, Ca., 1985), pp. 128-130.