This watch was fully described and illustrated by Reinhard Meis as one of the most interesting watches with tourbillon ever made, in Das Tourbillon, French Edition, Paris 1990, Editions de 1' Amateur, pp.192 to 195, fig. 226 to 234. It was then in an open face case and with another dial with subsidiary second on chapter III. It is also mentioned by Chamberlain in Its About Time", 1941, p. 449, where Major Chamberlain indicates: "I have a tourbillon lever escapement which was made by him but never put on the market; it has the escape wheel stationary and the anchor moving around with the cage ,five times per minute....". Apparently, Potter made only three watches with tourbillon in his life, an earlier one, No. 24, made circa 1857, now in The Time Museum, Rockford, Ill. and the third one, much later, circa 1890, described and illustrated by Daniel and Clutton in I,Valches, Fig. 324 a-b. Albert H. Potter (1836-1908) Born in Mechanieville, New York, Albert Potter began his threeyear apprenticeship in 1852 with Wood and Foley in Albany. He then established himself at 19 John Street and later at 84 Nassau Street, New York. There, in addition to repair work, he made some thirty five three-quarter plate movements, part with lever and part with detent escapements, cased in gold, which he sold for $225 to $350. In 1861 he went to Cuba where he continued the same kind of work for five years, adding to his designs a quarter repeater and a form of duplex escapement. Back in New York, he took out his first escapement patent in 1868 and soon afterwards moved to the West. I-Ie stayed in Minneapolis a short time and possibly in Milwaukee, but by 1870 he settled in Chicago. In 1872, with his brother William Cleveland Potter, he organised the firm Potter Brothers, which was dissolved in 1875, although the business was continued by W. C. Potter until his death. In October 1875, Potter took out patents on compensation balances and improvements in escapements for watches, assigning one half of his rights to John H. Mc Milian of Chicago. The latter may have been in partnership with Potter in his early venture in Switzerland. During his residence in Chicago, Potter designed and built a pocket chronometer which may be considered as his masterpiece. This watch was the prototype from which he made several examples in Geneva, where he obtained his Fermis 4'ElablissemenI on February I1, 1876. In an article in the Horological Journal of May 1882, Potter wrote that he invented, made drawings and working models of fourteen different escapements. Among these was also a tourbillon lever escapement which had the escape wheel stationary and the anchor moving around with the cage live times per minute, making the reversals of the momentum too rapid for good performance. Consequently, it was never sold and further examples were never made. As an improvement to that, Potter took a patent in 1886 for an escapement without escape wheel, first invented by Dcxhay in 1825 and brought out again by Mac Dowell at the London Exhibition of 1855. This patent, with others pertaining to the "Charmilles" watch, was assigned to the New Haven Watch Company for a reputed filly thousand dollars. The "Charmilles" watch was an attempt to produce good timekeeping movements at low prices. Albert H. Potter died on January 25, 1908, 23 rue Tronchin, in Geneva. Bibliography: Paul M. Chamberlain, It's About Time, 1941, pp. 445-450.