Swiss extremely rare silver deck watch caliber type II Circa 1906

Important silver open faced deck watch by Paul Ditisheim
–
An important and extremely rare Swiss deck watch calibre type II, in original mahogany case with numbered signature bone plate, circa 1906. This watch received the 3rd prize for securing the 31st place in the pocket chronometer 1st class category during the 1907 Neuchâtel test. In 1908, it won the 2nd prize for securing the 6th place in the deck chronometer category. The watch has a silver polished case with a reeded band and an engraved silver dome. The bone plate is signed by Paul Ditisheim, La Chaux de Fonds, Grand Prix Exposition Universelle, Paris 1900, 85 Prix de l’etat premier aux Concours Chronometriques des Observatoires de Kew, Washington & Neuchatel. It has a signed enamel dial with radial Roman numerals, auxiliary seconds, and blued spade hands. The frosted gilt 2/3 plate movement has a large bimetallic experimental Guillaume chronometer balance with two screws and two movable trapezoid weights, and a micrometre fine adjusting device.
–
Diameter: 63 mm
–
Weight: 204 g
–
Signed: Paul Ditisheim
–
According to the classification by Fritz von Osterhausen, this chronometer is fitted with a modified type II calibre. Osterhausen only verified six chronometers which use calibre II.
The chronometer at hand is a variant that has not been registered until now; its balance cock is curved and not straight. The experimental Guillaume balance has large regulation weights, which Ditisheim otherwise only employed in his decimal chronometer “Tropomètre” no. 16815 with “échappement à détente”. Marine chronometers usually feature this type of balance staff; here, the same design has been used on a smaller scale. The movement is unusual, too, in that it employs a regulation system with an uncommon micrometre correction device – until now, it has not been known that Paul Ditisheim had ever used such a construction. These distinguishing marks make this experimental marine chronometer one of the most interesting and outstanding timekeeping instruments from the house of Paul Ditisheim. Paul Ditisheim (1868-1945) was one of the most famous Swiss makers of watches and chronometers. He did most of his research and published his publications in precision timekeeping. He did his apprenticeship at the watchmaking school in La Chaux-de-Fonds before working in Ponts-de-Martel, Berlin, Paris, and Rotherham (near Coventry). In 1892, he opened up a watchmaking factory in La Chaux-de-Fonds. He presented his watches in many exhibitions and was very successful in designing pocket chronometers.