Silver pocket watch, by Isaac Grasset Geneva, 50mm, made in 1890s, like new, with patented crown-spring winding mechanism by Isaac Grasset. Enamel dial, arabic numerals, auxiliary seconds. Signed “Patent 5019 14528”, “Isaac Grasset Geneve”.

In the early 1880’s Isaac Grasset designed an interesting alternative power source in the form of a spring coiling up the stem (Swiss patent No. 120, later improved in No. 5019). In 1897 he patented a stem winding and setting mechanism for the arrangement, as found in this watch (Swiss patent No. 14528). He also patented an interesting constant force escapement and applied it to his design.