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| Maker - Henri Lepaute, Paris, France,
c.1814. Movement net, 29"h x 10 1/2"w x 5"d, 31"h x 12"w x 7"d with dome.
Two train, great wheel, Chevalier de Béthune escapement, half-seconds
pendulum on knife edge suspension, count wheel strike on hour and passive
strike on the half, gilt bezels and enamel dials indicating the day, month,
and date, 2 week duration, on two tone double marble base with ormolu
surround.
Shown above is a rear, left three-quarter view of the movement with a the Chevalier de Béthune escapement in the center. This escapement was never in wide use and examples of clocks with this escapement or somewhat rare.
Shown here is a close up of the view in the first picture. the circled area contain the the pair of escapement pallets, their associated forks, roller and escape wheel of the Chevalier de Béthune escapement. It is the lower pallet with its drive roller,as depicted by the lower arrow, that is connected to the pendulum. The roller is positioned within a fork that is attached to the second, upper pallet, upper arrow. This arrangement synchronizes the pallets for correct impulse and locking of the escape wheel.
The diagram above is one version of the Béthune escapement. The differences are that B and B' in the diagram are substituted with the roller and fork assembly. This modification eliminates the need for counterweight C. Point V is where the that pallet is connected to the pendulum. The following is the explanation of this diagram: Here we see an escapement combining two levers,
invented by the Chevalier de Béthune and applied by M. Thiout,
master-horologist, at Paris in 1727. P P' are the two levers or pallets
separately pivoted. Upon the axis V, of the lever P, is fixed a fork which
communicates the motion to the pendulum. The two levers are intimately
connected by the two arms B B', of which the former carries an adjusting
screw, a well-conceived addition for regulating the opening between the
pallets. The counter-weight C compels constant contact between the arms B
B'. The function is always the same, the recoil and the impulsion operate
upon the two pallets simultaneously.1 1. Clock and Watch Escapements, reprint from the 1904 compilation from the the Keystone, the organ of the jewelry and optical trades.
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