What is a French perpetual calendar clock?

Developed in the mid-to-late nineteenth century, these specialized timepieces incorporate complex horological mechanisms that display the time alongside calendar information, automatically adjusting for leap years and varying month lengths.

Which materials were traditionally used in nineteenth-century French clock construction?

Clocks from this period commonly featured cases milled from dense black slate or marble, complemented by gilded bronze mounts, brass clockworks, and hand-enamelled dial faces.

How can one identify authentic French movements from this era?

Authentic French clocks from the late nineteenth century typically feature round brass movement plates stamped with maker marks or serial numbers, alongside brocot escapements and mercury pendulum suspensions.

How should a slate mantel clock be styled within contemporary interior design?

Position the dark architectural form as a focal point on a fireplace mantel, sideboard, or study desk, balancing the visual weight with polished metal accents, leather-bound books, or modern artwork.

What maintenance is required to preserve a mechanical calendar clock?

Mechanical movements require professional servicing every five to seven years, consistent weekly winding, and delicate dusting of the slate case using a soft dry cloth while avoiding liquid cleaners.

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A French Perpetual Calendar Mantel Clock, C.1870.

Name: A French Perpetual Calendar Mantel Clock, C.1870.
Brand: Antique
SKU: SA1189355
Price: 3250 GBP
Availability: InStock

19th century

For Sale by FJ & RD Story Antique Clocks

Description

A fine quality 19th century French black slate perpetual calendar mantel clock with moonphase indication, by A Brocot & Delettrez, Paris, c. 1870.

The impressive drumhead case flanked by scrolled decoration, supported by reeded columns terminating in half round capitals, beneath the moulded stepped base. Opening cast brass bezels to the front and rear, with a further rear opening door, allowing for easy access to all controls and parts.

The 5” enamelled dial with Roman hours encircling a recessed centre with jewelled visible Brocot escapement set over another 5” enamelled dial giving full perpetual calendar information of month, day and date as well as moonphases. Both dials are in excellent original condition

The day of the month automatically corrects for the shorter months and thus takes the correct action on 28, 29 (for leap years), 30, or 31 day months.

The fully restored eight day twin barrel clock movement with circular plates united by four pillars and rack striking the hours and half hour on a single bell, stamped to the front plate A Brocot & Delettrez, Paris.

Both movements are of remarkable quality and design, in fully functioning restored order.

Original brass bob pendulum.

Finely fretted blued steel hands.

A very fine clock in excellent original condition with the movements fully restored.

The proportions of the clock are very good and it is an excellent size for displaying on a mantelpiece or side table.

All of our clock movements are restored by our horologist who is a Fellow of the British Horological Institute (FBHI), having 50 years of full time professional engagement in the repair & restoration of clocks, watches, music boxes & barometers. He was the recipient of the Worshipful Company of Clockmakers Bronze Medal.

All of our clocks have been sympathetically restored and have been expertly vetted for originality and good working order.

All clocks purchased from us are guaranteed for two years

Please contact us for further details and delivery information.

For overseas customers a fully insured shipment can be organised direct to your door for most locations in the world, please contact us for a shipping price.

(Antoine) Jean-Baptiste Delettrez (1 May 1816 – 25 May 1887) was a 19th-century French clockmaker.

Delettrez and Achille Brocot, son of the respected clockmaker Louis-Gabriel Brocot, established the clockmaking company "Brocot et Delettrez" in Paris on 20 October 1851, with premises at 62 Rue Charlot. Delettrez worked alongside Achille Brocot for several years and their clock movements are considered to be the most effective made during the late 19th century. Their speciality was a range of clocks based on the innovations of Brocot père and his other son Antoine, but generally of Achille's greatly advanced original design, some having a unique single-arm double-wheel escapement, some having a temperature-compensated pendulum, some having two dials, one of which showed the time and the other which showed a calendar and often other information such as phases of the moon, times of sunrise & sunset in Paris. The firm was awarded a 1st class prize at the Paris World Exposition of 1857 for a commercial clock of this type.

This innovative and fruitful partnership continued until the death of Brocot fils in 1878, after which event Delettrez continued on his own.

Louis Achille Brocot, 11 July 1817 – 19 January 1878, was a French clockmaker and amateur mathematician.

He is known for his discovery (contemporaneously with, but independently of, German number theorist Moritz Stern) of the Stern–Brocot tree, a mathematical structure useful in approximating real numbers by rational numbers; this sort of approximation is an important part of the design of gear ratios for clocks.

Several improvements in clock design were attributed to Brocot.

Physical Dimensions

Height

41cm (16.14")

Width

38cm (14.96")

Depth

15cm (5.91")

Declaration

FJ & RD Story Antique Clocks has dated this French Perpetual Calendar Clock to the 1870s.

Reference Numbers

Sellingantiques Reference

SA1189355

Dealers Internal Reference

Perpetual/26

Description

A fine quality 19th century French black slate perpetual calendar mantel clock with moonphase indication, by A Brocot & Delettrez, Paris, c. 1870.

“

The impressive drumhead case flanked by scrolled decoration, supported by reeded columns terminating in half round capitals, beneath the moulded stepped base.

FJ & RD Story Antique Clocks

Opening cast brass bezels to the front and rear, with a further rear opening door, allowing for easy access to all controls and parts.

fig 1. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 1. A French Perpetual Calendar Mantel Clock, C.1870.

The 5” enamelled dial with Roman hours encircling a recessed centre with jewelled visible Brocot escapement set over another 5” enamelled dial giving full perpetual calendar information of month, day and date as well as moonphases. Both dials are in excellent original condition

fig 2. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 2. A French Perpetual Calendar Mantel Clock, C.1870.

The day of the month automatically corrects for the shorter months and thus takes the correct action on 28, 29 (for leap years), 30, or 31 day months.

The fully restored eight day twin barrel clock movement with circular plates united by four pillars and rack striking the hours and half hour on a single bell, stamped to the front plate A Brocot & Delettrez, Paris.

fig 3. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 3. A French Perpetual Calendar Mantel Clock, C.1870.

Both movements are of remarkable quality and design, in fully functioning restored order.

Original brass bob pendulum.

Finely fretted blued steel hands.

A very fine clock in excellent original condition with the movements fully restored.

fig 4. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 4. A French Perpetual Calendar Mantel Clock, C.1870.

The proportions of the clock are very good and it is an excellent size for displaying on a mantelpiece or side table.

All of our clock movements are restored by our horologist who is a Fellow of the British Horological Institute (FBHI), having 50 years of full time professional engagement in the repair & restoration of clocks, watches, music boxes & barometers. He was the recipient of the Worshipful Company of Clockmakers Bronze Medal.

fig 5. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 5. A French Perpetual Calendar Mantel Clock, C.1870.

All of our clocks have been sympathetically restored and have been expertly vetted for originality and good working order.

All clocks purchased from us are guaranteed for two years

Please contact us for further details and delivery information.

fig 6. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 6. A French Perpetual Calendar Mantel Clock, C.1870.

For overseas customers a fully insured shipment can be organised direct to your door for most locations in the world, please contact us for a shipping price.

(Antoine) Jean-Baptiste Delettrez (1 May 1816 – 25 May 1887) was a 19th-century French clockmaker.

fig 7. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 7. A French Perpetual Calendar Mantel Clock, C.1870.

Delettrez and Achille Brocot, son of the respected clockmaker Louis-Gabriel Brocot, established the clockmaking company "Brocot et Delettrez" in Paris on 20 October 1851, with premises at 62 Rue Charlot. Delettrez worked alongside Achille Brocot for several years and their clock movements are considered to be the most effective made during the late 19th century. Their speciality was a range of clocks based on the innovations of Brocot père and his other son Antoine, but generally of Achille's greatly advanced original design, some having a unique single-arm double-wheel escapement, some having a temperature-compensated pendulum, some having two dials, one of which showed the time and the other which showed a calendar and often other information such as phases of the moon, times of sunrise & sunset in Paris. The firm was awarded a 1st class prize at the Paris World Exposition of 1857 for a commercial clock of this type.

fig 8. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 8. A French Perpetual Calendar Mantel Clock, C.1870.

This innovative and fruitful partnership continued until the death of Brocot fils in 1878, after which event Delettrez continued on his own.

Louis Achille Brocot, 11 July 1817 – 19 January 1878, was a French clockmaker and amateur mathematician.

fig 9. An antique black slate French mantel clock featuring two stacked circular dials, including an upper time display with Roman numerals and a lower perpetual calendar with a moonphase indicator. — fig 9. A French Perpetual Calendar Mantel Clock, C.1870.

He is known for his discovery (contemporaneously with, but independently of, German number theorist Moritz Stern) of the Stern–Brocot tree, a mathematical structure useful in approximating real numbers by rational numbers; this sort of approximation is an important part of the design of gear ratios for clocks.

Several improvements in clock design were attributed to Brocot.