German important and extremely rare pocket watch Circa 1886

Pocket watch with full calendar by A. Lange & Söhne
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A German important and extremely rare gentleman’s Glashütte pocket watch with a full calendar, circa 1886. Made like the patent Fleischhauer by Moritz Großmann – sold in 1885 for the sum of 412 Marks.
18-Carat rose gold case with engraved monogram. Signed white enamel dial with a date indication by numerals and lettered rings affixed outside the dial, a subsidiary dial for the seconds, and decorative gold hands. 4/5 plate movement with gold screw compensation balance.
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Diameter: 51 mm
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Weight: 114 g
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Signed: A. Lange & Söhne Glashütte B/Dresden
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Calendar watch movements of Fleischhauer’s patented design made by Moritz Grossman (and taken over and sold after his death by A. Lange & Söhne) are easily identifiable from the following characteristics: – date indication by numerals and lettered rings affixed outside the dial and connected with the train by an internal gearing. – winding as well as setting the hands and the date work through a strong racking bar that is typical for Grossmann; it is operated by two pushers on each side of the winding pendant.
Otto Fleischhauer in Berlin had the idea to create a calendar watch and supplied his drafts to the patent office in Berlin on July 15, 1883. The drafts had no exact concept as to which parts were needed or of the proportions of the mechanism. To put his design into practice called for a completely novel construction, so Fleischhauer asked Moritz Grossmann to create this new timepiece and Grossmann built an entirely new type of watch; his ideas are apparent in the drafts of this watch.
In 1884 Fleischhauer patented the construction in England as well, however, he offered the patent for sale only a year later after Grossmann died.
According to the records of the Glashütte museum, the 20 watches Grossmann had already produced were all taken over and sold by Lange & Söhne; as far as they are traceable, they were also all signed by Lange & Söhne on dial and movement. An exception is the first watch with number 6141 and the other watches of the small first series with numbers 8262, 8263, 8264 and 8265 they are neither signed on the dial nor are they listed in Huber’s “Lange list” of 1999.