The case and dial of this watch are engraved with designs of inhabited foliage and grotesque ornament, the latter having its inspiration in the engravings of the French artist Jacques Androuet DuCerceau (ca. 1512–ca. 1585). The side, or band, of the case is pierced to permit the sound to be heard when the watch strikes the hour (1–12) on the bell attached to the inside of the bottom of the case. A single hand indicates the hours and the half hours marked in the silver chapter ring applied to the dial. A small hand attached to a disk that revolves inside the chapter ring indicates the moon's age in its monthly cycle, and an aperture in the disk displays the phases of the moon. Further, the length of time of moonlight after sundown can be read at the edge of the disk, and in its center there is an aspectarium showing the changes in the angular distance between the sun and the moon in the zodiac, information useful for astrological purposes.
[Clare Vincent, 2009]