An elegant early 19th-century clock
The overhanging cornice with ormolu dentil moulding supported on four turned Corinthian columns on a plinth base with engine-turned bun feet.
The signed white enamel Roman dial with minute track and blued steel open moon hands, the minute hand counter-balance, engine-turned centre within a cast ormolu bezel.
A large twin-train movement with circular plates, pinwheel escapement to a heavy temperature-compensated gridiron pendulum formed of four steel and four brass rods, with micrometer beat adjustment and knife edge suspension, the strike train with large outside countwheel acting on a bell.
Gridiron pendulum temperature-compensated features
In ordinary clock pendulums, the pendulum rod expands and contracts with changes in temperature. The period of the pendulum’s swing depends on its length, so a pendulum clock’s rate varied with changes in ambient temperature, causing inaccurate timekeeping.
The gridiron pendulum consists of alternating parallel rods of two metals with different thermal expansion coefficients. A-frame connects the rods in such a way that their different thermal expansions (or contractions) compensate for each other, so the overall length of the pendulum, and thus its period stays constant with temperature.
Pierre Alexandre Poux Landry
Pierre Alexandre Poux Landry worked as a clockmaker in Paris, listed in the “Almanach du commerce de Paris, of 1811”, with his atelier in des Rue Filles-Dieu, 31. Landry granted the title of a master in 1787.
Des Panoramas, Cleret
We assume that the signature “des Panoramas, Cleret” refers to one of the earliest venues of the Parisian trade. It was one of the first covered commercial passageways in Europe. Where probably Pierre Alexandre Poux Landry opened an atelier to sale his clocks and pocket watches.