A French pendule à planisphère from the Wallace Collection

The Wallace Collection is a national museum in an historic London town house. Its 25 galleries are filled with unsurpassed displays of French eighteenth-century painting, furniture and porcelain, superb Old Master paintings and a world class armoury. Its collection of clocks includes over 30 French clocks of great beauty.

The Wallace Collection in London is renowned amongst other things for its magnificent collection of French eighteenth-century furniture, much of which has a royal provenance and once furnished the palaces of the ancien régime. However, the royal family was but one source of patronage in the decorative arts of the eighteenth century and the Wallace Collection also contains splendid and costly furniture that was commissioned by the super-rich of their day: wealthy bankers and financiers. One such piece is the magnificent pendule à planisphère, or astronomical clock, which dates from c. 1750 and was commissioned by the king’s banker, Jean Paris de Montmartel (1690-1766); this clock is testament not only to Montmartel’s enormous wealth, but also to his interest in scientific and technological developments of the time – indeed similar to many collectors of watches and timepieces today.

An important feature

Montmartel kept his clock in his Parisian home, the Hôtel Mazarin, in his grand cabinet (study). This is a room where he would have conducted business and held meetings with his fellow financiers and this clock was no doubt an important feature designed to impress his peers – we know that he was proud of it because it features prominently in a portrait of him sitting at his desk in the study. Not only was the clock able to tell him the time in Paris down to the last second (both solar and mean), it was also possible for him to read off the times in any part of the northern hemisphere; from this clock he could also tell his visitors the day and date of the month, the sign of the zodiac and the times of the rising and setting of the sun and moon

http://journal.hautehorlogerie.org/en/article/a-french-pendule-a-planisphere-from-the-wallace-collection/