Creighton & Black, New York, No. 2398, circa 1850.Very fine and rare, palisander and gilt brass marine chronometer with 56-hour power reserve.

C. Three-body, with brass handles, all the edges protected by a heavy brass inlay, the glazed upper section with hinged lid. Brass bowl and gimballed suspension. D. Silvered with Roman numerals, outer minute ring, subsidiary seconds and up-and-down scale. Gold "Spade" hands. M. 80 mm, gilt brass full plate with column pillars secured by screws, 13 jewels, fusée with chain and maintaining power, Earnshaw-type spring detent escapement, two-arm Creighton-Bliss's patented cut bimetallic compensationbalance with wedged temperature adjustment weight and mean time adjustment nuts, freesprung blued steel helical balance spring with terminal curves.Dim. Bowl 104mm, box 19x19x19cm.

David Munro and Erika Johnson, New Jersey, made in 2002.Very fine and rare, brass-mounted, marble hour and half-hour striking table regulator, with two-second remontoire and a spe-cial compensation pendulum.

C. Two blocks of green verde marble joined by black molded marble section, small extended marble molding at the top supporting the movement. D. White enamel, flat, Roman numerals, outer minute ring. Blued steel "Breguet" hands. M. Hump-back-shaped, solid brass, visible Graham dead-beat escapement with sapphire jeweled pallets, driven by 15-tooth wheel, jeweled upper train pivots for a total of 10 jewels, differential remontoire rewinding on each third tick, the arbor which carries the seconds had has a drive wheel and a 30 tooth locking wheel mounted on the same collet. This locking wheel is held by a blued steel detent. Pivoted on an arbor directly behind the escape wheel is a frame, with an adjustable knurled weight. This frame carries an idler gear of the same count as the escape pinion. Each advance of the escape wheel is powered by a drop of this weight. A steel pin on the frame raises with each drop, and on the third tick lifts the detent, releasing the lower train, rewinding thweight, and advancing the hands. The mass of this partially counterpoised frame avoids the need for a fly with its attendant problems. The 2/3-second pendulum is supported by a substantial bracket screwed to the top of the back plate. The suspension travels in the bracket with knurled adjusting screws for fine beat setting. The pendulum adjusts for temperature differences through Garnier's visually important "dumbbell" system of bimetallic compensation. As the steel rod expands with an increae in temperature, the brass side rods extend further, raising the pivoted compensation weights. The weights can be moved to adjust the compensation.The solid brass beat scale is a separate element, engraved on the pendulum circumference. The clock has a conventional count wheel strike, striking a bell at hour and half hour.Signed "Arcadian Clock Co." on the back plate.Dim. Height 60cm (24"), width 22cm (8.5"), depth 14cm (5.5").