Longcase clock by Leonard Salzer

Catalogue description — Royal Museums Greenwich

The weight-driven movement is held within a mortise and tenoned oak frame. The four-wheel going train consists of three wooden wheels; the teeth are cut onto segments which are mortised around the rim (in the same manner used by a mill-wright in constructing large geared wooden wheels). The brass sixty-toothed escape wheel runs on paired anti-friction wheels. The wooden teeth engage with lignum vitae rollers running on brass pins enclosed by two brass shrouds mounted to the shaped and ringed box wood arbors. The arbors have brass pivots which run in lignum vitae bearings. The minute wheel is mounted to the second wheel arbor and drives a cocked cannon pinion and hour wheel. The third wheel has twenty-one brass pins which engage with the maintaining power lever. An oak bowl with paper seconds scale is mounted to the extended front pivot. The grasshopper escapement is Harrison’s second type with co-axial oak pallets within a brass frame, the brass composers are set by two brass pins running through the frame. The pallet frame is mounted to a brass arbor with knife edges on glass plates. The pendulum has a spring suspension which is mounted within brass cycloidal cheeks which are adjustable in three places. The gridiron pendulum has a smaller upper grid and a ‘tin-whistle’ adjuster to the lower grid, and a brass faced lead bob. A reconstruction of the Harrison 1726 regulator by Len Salzer, 1988-1990. The maintaining power is activated by a brass lever within a slot to the upper right-hand side of the dial. When activated the lever pulls back a shutter in the form of false end to the winding square allowing the key to be inserted. The striking train employs wooden wheelwork and is laid out in the same manner as a standard striking train of the day but with lignum rollers to lift the hammer tail. The hammer is pivoted within a turret mounted above the bell. The twelve-inch oak dial has a black spirit varnish ground which is decorated with floral and symbolic motifs, has an applied brass chapter ring with pierced blued steel hands, seconds aperture and calendar to the arch above the signature James Harrison. The pine case is polished throughout with a black spirit varnish and is lightly decorated with floral motifs. The hood is surmounted by an elevated caddy with two gilt wood ball finials and a hidden aperture over a moulded cornice, glazed side apertures and break arched door with two integral pillars. The sides of the trunk and plinth are mitred from top to bottom as is the original clock. The moulded door has a Dutch arch, glazed aperture with hand written equation of time table and moulded lenticle to the centre.