most likely American.
c. second half 1800's. Brass and bronze hybrid flat bed frame design.
Strike train frames one-half inch thick, going train three-eights inch
thick. Hour strike using rack
and snail system with quarter strike using a count wheel. Jeweled four legged gravity
escapement using jeweled anti-friction wheel impulse rollers. Mercury compensated
pendulum. Eight day duration (three day in current configuration). 27"w x 22"h x
Pendulum with dual mercury glass jars each holding about 10 lbs. of mercury.
Coarse adjustment achieved through rating but at bottom of pendulum, fine
adjustment in the middle of the glass jar pair. The entire scale is equal to
one tenth turn of the lower rating nut. beat plate below rating nut.
The jars can be tilted away from the pendulum by turning the pair of 'ship's
wheels" to lift the top plates off the top of the jars.