Similar watch described and illustrated by Reinhard Meis inLe Tourbillon, Editions de l'Amateur, Paris 1990, pp. 45-50and 165.Paul Ditisheim (1868-1945) was born on October 28th, 1868, in La Chaux-de-Fonds, Switzerland, and died in Geneva, on February 7th, 1945. After early training in Switzerland, he studied in Berlin and Paris, arriving in 1891 to England, where he worked as a technician at the Rotherham factory in Coventry.He started his own manufacture at Chaux-de-Fonds in 1892, specialising in very high precision watches and in jewellery watches. Success in both spheres followed rapidly, and he won many honours for adjusted watches, especially at Neuchâtel and Kew Observatories.He collaborated with Dr. Ch. E. Guillaume in the use of both the Guillaume "integral" balance and the elinvar-type of auto-compensating balance spring. He also contributed many papers to scientific and horological journals, and was associated with Dr. Paul Woog, an oil chemist, in the development of Chronax oils.It is unlikely that Paul Ditisheim had very much to do with the actual construction of his watch, other than to order its production from specialist suppliers. He probably was responsible for the springing and adjusting, at which he was a noted specialist.