738 - Badische Uhrenfabrik anniversary clock, torsion ball pendulum under glass dome, brass, circa 1920

Badische Uhrenfabrik anniversary clock, torsion ball pendulum under glass dome, brass, circa 1920 Brass and glass, torsion pendulum clock, also known as anniversary clock, as a table clock, by the Badische Uhrenfabrik, dial and movement marked "CB", round moulded brass base, two columns supporting the movement with pierced cresting, white enamel dial with black Arabic numerals and minute track, black hands, key-wound movement, brass torsion pendulum with four balls, without key, under glass dome, used condition commensurate with age, clock starts running, D. 20 cm, H. 24 cm (with glass dome). 360-degree photo available on our website. The torsion pendulum clock, also known as torsion clock or anniversary clock, has, instead of a swinging pendulum, a pendulum suspended from a thin wire, which rotates about the vertical axis and thereby twists the wire; one oscillation usually takes twelve to twenty seconds, which is why the movement keeps running for a year or longer on one winding. Anton Harder invented and patented this clock in 1879 to 1880 and founded the Jahresuhrenfabrik; after the sale of the patent in 1884 and its expiry in 1887, series production by several manufacturers began in Germany. The glass dome protects the delicate pendulum from draughts. In the 1920s the Badische Uhrenfabrik Furtwangen AG in the Black Forest produced, besides clocks, also radio receivers under the brand Baduf.