Accompanied by République et Canton de Neuchâtel Observatoire Astonomique et Chronométrique duplicata of the Bulletin de Marche dated 31 December 1936.
The present watch is fitted with the observatory caliber 355AN which was developed in 1927 especially for the participation at timing contests. The movement has two remarkable features, the impressive size of a 64 mm. diameter and the finely finished escapement constructed in order to allow disassembling of all components separately. This construction facilitates precision adjustment and allows an easy exchange of individual parts.
It appears that a total of 48 examples of this caliber were made, out of which only six movements with a spring chronometer escapement. The first series of 9 movements numbered 355001-355009 was produced in 1927, the second series comprising 39 movements numbered 360481-360519 as of 1929.
The present watch numbered 360501 is from the second series and achieved the first price in the category pocket chronometers during the Neuchâtel Observatory timing contest in 1936. It was adjusted by the renowned precision adjuster W.A. Dubois (1879-1952) who also worked for P. Ditisheim, Ulysse Nardin and others.