German gold Glashütte open faced pocket watch Circa 1896

Open faced gold pocket watch by A. Lange & Söhne
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A German exquisite Glashütte pocket watch with chronograph and 30 min. counter, circa 1896.
Manufactured in quality 1A and sold to watchmaker Richard Tüllmann, Dresden, Gluckstraße 2 for 804 marks on August 20th, 1896, with Lange extract from the archives.
The case is 18 carat pink gold, engraved and engine-turned monogram with blue enamel inlay. The signed dial is white enamel with red and black Arabic Numerals, two subsidiary dials, center seconds and decorative gold hands. It has a 3/4 plate movement and a gold screw compensation balance.
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Diameter: 51 mm
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Weight: 106 g
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Signed: A. Lange & Söhne Glashütte B/Dresden
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In the early 1870’s Richard Lange (1845-1932) started designing a new chronograph which had the mechanism above the train, so that the mechanism could be attached to a “normal” watch movement. The upper seconds bearing received a new bridge and acted as the bearing for the clutch lever. A central chrono wheel with an upper steel bridge was fed through the minute wheel and all levers and springs were highly ground and bevelled. The mechanism was operated by a pusher in the crown, with the sequence being start, stop and reset. The most basic version only had one chronograph hand, chronographs with minute counters were much more complicated.