Rare Swiss silver eight day lever with visible balance Circa 1920

Silver Hebdomas pocket watch
–
A rare Swiss silver open faced Hebdomas pocket watch, circa 1920. The keyless eight day movement with a lever escapement. Off white enamel dial with off center time indication featuring black radial Arabic hour numerals in round cartouches and blued spade hands, decoration on either side, a gilt, finely engraved bridge below over a visible balance. A plain case. Dial signed 8 days – 8 Jours – 8 Tage.
–
Diameter: 50 mm
–
Weight: 92 g
–
Signed: No name
–
The name Hebdomas is derived from the Ancient Greek word for week/the seventh day. It refers to the watch’s ability to run for at least a week on a single winding.

A Hebdomas pocket watch is a timepiece known for its eight day, hand wound movement, off center time indication and a visible balance wheel mounted to a dial side bridge, a feature that makes Hebdomas watches instantly recognizable, and is typically gilded and engraved with a decorative floral motif. A massive mainspring barrel covers the entire diameter of the movement, rotating around the center similar to an automatic rotor.

Most Hebdomas watches feature the name centered in the dial and 8 Jours engraved on either side of the balance. Mostly also featuring a flower or arrow design above.