Nicole, Nielsen & Co. signed relatively few watches, however, they were well known in England as important suppliers of movements to such prominent firms as Charles Frodsham, M. F. Dent, and E. J. Dent & Co. Vaudrey Mercer - biographer of Edward John Dent and others famous English watchmakers - states that the Nicole Nielsen company fitted the majority of their tourbillon watches with English lever escapements and that therefore the watches that had a spring detent escapement were regarded as of superior standard. Reinhard Meis - the pocket Chronometer tourbillon specialist - emphasises how rare these tourbillons were, even claiming that only approximately 650 top quality vintage tourbillons were ever produced worldwide. Around 100 of those were created in England. Meis also mentions that, bar one exception.ne but the English makers fitted their tourbillon watches with powerful complications. New discoveries record a slightly higher overall number, but nevertheless tourbillon watches are rare and highly coveted. At the time when this watch was created, the Dents were working in two different family businesses that had been established after the death of Edward John Dent. The watch was produced by the company of M. F. Dent (Marianna Frederica), which was the name of Richard Edward Dent's widow. The second business traded as E. Dent (Elizabeth) & Co. In 1920 both businesses came together again as one company that took the name Dent. Dent, John Edward (London, August 19, 1790 - London, March 8, 1853) Englishman noted for his design and construction of fine and historically important precision clocks and chronometers. Dent was apprenticed to Edward Gaudin in 1807 and may also have learned something of the clockmaker's trade from his cousin Richard Rippon. During the period 1815-29 Dent established a reputation as a builder of accurate chronometers. His fine work eventually brought business from the Admiralty and the Royal Greenwich Observatory. Beginning in 1826, Dent submitted chronometers to the observatory's annual timekeeping contests, finally winning the 1829 First Premium Award of A£ 300. From 1830 until 1840 he was the partner of John Roger Arnold in the manufacture of chronometers, clocks, and watches, and by 1847 he was the proprietor of three shops in London. Dent won the esteem of Sir George Airy (1801-1892), the astronomer royal, who supported him as the maker of a large clock for the tower of the new Royal Exchange. Dent established a workshop in the Strand to produce this excellent timepiece, which was installed in 1844. In 1852 Dent won the commission to make the great clock - now called Big Ben - for the Houses of Parliament at Westminster, but he died before completing the project. Upon the death of Rippon, Dent had married his widow, whose sons Frederick and Richard took Dent's name and succeeded to his business. Frederick Rippon Dent's company finally installed Big Ben in 1859. What is a tourbillon? The tourbillon mechanism cancels out the variations in rate due to gravity; it's one of the most remarkable creations in watchmaking history. It consists of a circular mobile carriage holding all the escapement components, with, in its centre, the regulating organ. The carriage generally completes one revolution per minute; this rotation compensates the negative effects of gravity on the escapement and in particular on the balance-wheel.