German historically important pocket watch with date Circa 1800

Open faced verge pocket watch by Louis Auch jun.
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A historically important astronomical German verge pocket watch with date, weekday and moon phase and cylinder escapement, circa 1800.
20 carat gold case; white enamel dial with Roman hours, Arabic minutes, Breguet hands and in the center four subsidiary chapter rings for the auxiliary seconds, date, weekday and moon phase; full plate movement, chain/fusee and five-arm balance.
The large, open work balance cock of this slim pocket watch covers almost all of the movement plate and also conceals the signature “Auch jun. à Louisburg”.
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Diameter: 53 mm
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Weight: 89 g
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Signed: Auch jun. à Louisburg
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Jakob and Louis (Ludwig) Auch
Jakob Auch was born in Echterdingen on February 22, 1765, and died in Weimar on March 20, 1842. He lived in Echterdingen until 1787 and later in Vaihingen and Seeberg before moving to Weimar in 1798 to become engineer to the court. Auch was one of the most able pupils of Philipp Matthaeus Hahn and created many pocket watches in the style of his famous master. He probably took his son Louis (Ludwig) into his business before 1800. One of the pocket watch is signed “J. Auch und Sohn, Weimar” (J. Auch and Son, Weimar).