Maker - Henri Lepaute, Paris, France, c.1810. Movement net, 22 1/4"h x 14 3/4"w x 5"d. Two train, great wheel, pinwheel escapement, half-seconds pendulum on knife edge suspension, count wheel strike on hour and passive strike on the half-spring driven, gilt bezels and enamel dials indicating the day, day's zodiacal sign, date, month and season, 2 week duration on a dual weight driven drop of 11 1/4" or 28.5 cm on Sienna Italian marble base.

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Weight driven table-top skeleton clocks are rare because of the precision workmanship needed to get a week, or as in this case, a two week duration from the limited drop available for the weight(s). In this clock the weight has just over 11" for a two week duration and are not compouded. One and three-quarter turns of the great wheel barrel is all that is needed to fully wind the weights and run the escape wheel which turns twice a minute for two weeks or 40,320 revolutions. One way to achieve the very high gear ratios needed for this is to employ the 'great wheel' design seen in some skeleton clocks where the main wheel is greatly over-sized. This allows the train to have the normal compliment of four wheels that one might find in a standard eight day spring driven clock. What the great wheel accomplishes is the same as if there were an extra wheel in the train, or five. Of course no matter whether one uses a great wheel or five conventional wheels, the ratios needed to step up the gearing from the main wheel to the escape wheel are the same. The higher this ratio is, the more susceptible will be the following wheels in the train, and especially the escape wheel to stoppages due to any sources of friction or other imperfections; thus the need for better quality in the fabrication and finishing of all of these components and therefore the greater cost of such clocks.

The pendulum is one-half seconds beating with a 30 pin escape wheel resulting in that wheel turning around twice per minute. The second hand is mounted to the arbor of the escape wheel so it makes one complete revolution in 30 seconds or two per minute! A very odd arrangement and somewhat disconcerting when first observed, but not at all unpleasant. It brings a lot of liveliness to the presentation. Of course Lepaute could have gotten around this problem by using a coup perdu type of escapement or doubled the compliment of pins on the escape wheel, although the latter would have been impractical without a concurrent increase in the diameter of the pinwheel itself. Given the high gear ratio, the lighter the escape wheel the better and this also implies smaller.