A fine George III mahogany longcase regulator
signed "Josiah Emery, Charing Cross. London," circa 1785
Case: The mahogany veneers of good figuring set on an extremely substantial tapering case of solid mahogany, the shallow arched hood with canted front angles over the conforming trunk door and spreading base on double apron, the interior of the case fitted with sliding glazed panels forming a partition to enclose the pendulum and offer a microclimate.
Dial: the one-piece silvered dial signed in the shallow arch 'Josiah Emery, Charing Cross, London' over a concentric Arabic minute ring with blued steel heart-tipped hand, enclosing the Arabic subsidiary seconds dial with Observatory marks and extremely fine seconds hand, the hours shown in a sector-shaped cartouche below centre (the hour ring engraved on both sides; 1 - 24 on one side and twice 1 - 12 on the other), secured to the front-plate by four heavy dial feet, each with three screws.
the plates measuring 5mm in thickness and united by six knopped pillars, the movement protected by sliding brass shutters running in grooves at the plate edges, set on a heavy mahogany seatboard. The dead beat escapement employing an unusual V-shaped anchor having curved impulse pallet faces with concave entrance and convex exit surfaces intended to equalize impulse, Harrison's maintaining power, fully end capped high-count train with the 'scape wheel and anchor arbors jewelled, all wheels finely cut and with six crossings.
The gridiron pendulum of the form introduced by John Arnold, consisting of two zinc and three steel rods, suspended from a substantial back cock on the movement, beat adjustment by means of screws on the suspension block, pendulum rod fitted with an open work, lozenge-form, brass and steel brace to engage the crutch, large brass-clad bob pierced with rectangular openings forming a bridge acting as the point of suspension, placing the bob's center of gravity on a screw threaded into the lowest cross piece of the pendulum, rate adjustment by means of calibrated rating scale on this screw, a further spherical fine adjustment weight below the bob the screw terminating with an index to the silvered beat scale within the case.
2.01m (6ft 7ins) high.
Clocks and Watches
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