Albert H. Potter & Co.
A yellow gold open-faced keyless pocket chronometer, No. 721, Circa 1880
Movement: Potter's patented detent escapement and bridge layout, free-sprung regulator, blued steel helical hairspring, jeweled to the center carried in gold chatons, bi-metallic compensation balance, the balance bridge signed Albert H. Potter & Co., Pat. Oct.11.75., Geneva, Plate desn. Pat. Jan. 4.76., No. 721, balance cock signed ESCAPEMENT, Pat. Oct.11.75. Dial: white enamel dial, Roman numerals, subsidiary dial for constant seconds at 3 o'clock, signed Albert H. Potter & C o , Geneva Case: 18k yellow gold, glazed cuvette, inside case back numbered 68712 and 137 Signed: dial and movement Diameter: 55 mm Accessories: Accompanied by an invoice from Greenberg Rarities, New York, dated March 5 th 1975, listing the price as $10,692.000Albert Potter is considered one of the finest American chronometer makers, and the present lot exemplifies his mechanical ingenuity. The watch features several of Potter's exceptional designs, such as his pivoted detent escapement, which contains a special arrangement for the spring in order to make the passing action as smooth as possible. His design for the balance, which he patented on 11 October 1875, sees a single pin set into the end of the escape wheel cock, providing banking for the detent. This makes an adjustment for locking unnecessary. This piece also showcases Potter's plate design, which allows the wearer to more easily set the train. He patented this design on January 4th, 1875. Although not stamped with Potter's trademark, the case of the present lot typifies Potter's style. It was likely exported to America and cased there in order to avoid the high tariffs on Swiss-made gold cases imported into the United States. See Masterworks of Time, Part III, Geneva, June 16,2020, lot 12 for another Potter pocket chronometer, no. 85 with a very similar American made case. It should be noted that the Potter no. 85 case was numbered 687709 three numbers away from the present lot. The case is also stamped 137, suggesting the possibility that the case was made by the same American Case maker.
