c.1870 Rare Large French Astronomical Perpetual Calendar Four Glass Clock

Dial

The outside chapter for the time dial has black Roman numerals for the hours, the fast/slow arbor above the twelve, nicely finished steel Breguet-style hands and a matching sweep seconds bit. The sunken center carries the outside escapement, a lunar aperture and the retailer's signature, 'JW Benson, London'. Below are the white porcelain subsidiary dials with black lettering, gold accent marks and steel indicator hands. They include sunrise, sunset, day, date and month. Centered is the polychrome porcelain equation of time dial with a steel-cut indicator hand that carries a gilt-bronze sun. and a sector aperture that shows the polychrome dial with the twelve zodiac symbols each framed by elaborate gilt-work. Framing the wonderful dials is an elaborate gilt-bronze mask with engraved scrolling foliage against a chased ground.

Movement

The eight-day time and strike movement has shaped plates, an outside escapement with jeweled pallets, a sweep seconds hand, a Brocot suspension, an adjustable crutch, is stamped 'AB' in a star and '1325' and '24 8' on the backplate, a glazed compensating pendulum and strikes on a large coiled gong mounted to a wooden board in the base. The large perpetual calendar mechanism is mounted below the clockwork, is set off the back plate and has a trip lever that is activated by the strikework. The complications include day, date, month, sunrise, sunset, moondial and equation of time.