The clock has a bell-shaped hood or bonnet, with three spool-turned wooden finials above a blind-carved acanthus frieze and a projecting compound-moulded cavetto cornice. The works are contained in a case with an arched glass door and flanking turned corner colonettes. The clock dial is inscribed "Edwd. Duffield, Philadelphia." A chapter ring is silver, with black painted Roman hour numerals; another has black Arabic minute numerals. The faceplate is brass. Cast brass spandrels at the four corners show heads in profile, wearing feather headdresses; they may originally have been gilded. There is a sunken seconds dial, a keyhole and a square aperture displaying the date letter. Above the dial is a lunette through which is visible a silver and black moon sphere. A small cylinder below it shows the days of the phases of the moon. The waisted case has a plain, arched door with thumbnail-moulded edges. The door now bears two silver dedicatory plaques. The base of the case is plain, with a cavetto-moulded top and very shallow bracket feet.