German extremely rare early silver pocket watch Circa 1855

Open faced pocket watch by Adolph Lange
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An extremely rare, early Glashütte pocket watch with pin-pallet escapement from A. Lange‘s experimental period, circa 1855.
Polished silver case. Enamel dial with radial Roman numerals, outer minutes track, and spade hands. Half plate movement, screw compensation balance. Dome signed: Patent – Anchor, A. Lange, Dresden.
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Diameter: 48 mm
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Weight: 71 g
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Signed: A. Lange, Dresden
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This keywind pocket watch was created in the very early years of the Glashütte watch industry, the ébauche was probably created as early as 1848/1849. At that time Adolph Lange favoured pin lever escapements, which were easy to produce and which, he felt, had some technical advantages. Another Glashütte watch dating from 1848 that had an identical movement but with a lever with a long fork (similar to the levers used in Glashütte later) indicates that the tests and experiments at the time resulted in all kinds of different constructions.
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Ébauche
An unfinished movement sold as such. Until circa 1850, a ébauche comprised only the plate, bridges, fusee and barrel. It was known as a blanc and was finished at the établissage.
The modern ébauche is a watch movement, with or without jewels but always without its regulating organ, mainspring, dial and hands. It is also known as a blanc roulant.