The OUTER SIDE of the UPPER LEAF has a nocturnal (missing the arm) and a perpetual calendar around the rotating volvelle. The names of the months are inscribed in Latin and the scale is divided to ten, subdivided to two days, numbered by ten from ten to 30 or 31 or 28 as appropriate. The juxtaposed indexed volvelle has hours engraved from 3 to 12 to 9 with small touch pins (the one corresponding to 4 a.m. is missing), spherical except for the one for 12. Small rectangular apertures reveal inscriptions for latitude 54 (repeated twice) and the lengths of the day and night, each from 8 to 16. Inner circles are engraved with similar inscriptions for latitudes 51 and 48. The equinoxes are at 10th March and 13th September. The inner circle is engraved with strapwork and foliage, and the arm was kept by means of a rosette knob. The spandrel area is filled with heart-shaped strapwork and foliage. The INSIDE of the upper leaf has a pierced volvelle with aspectarium. The volvelle itself is engraved with lunar hours; surrounding the volvelle are engraved solar hours; both are divided to the half hour and numbered 1 to 12 twice. Surrounding the hours is an inscription and around this are the names of the 16 main directions in German. There is a central hole for a vane, now missing. The spandrel area is filled with decoration similar to the outside of the leaf. The inside of the main BOX has a polar gnomon horizontal dial, with common hours engraved alternatively from 5 to 12 to 7 and from V to XII to VII, with punches for the half hours, for the latitudes 45°, 48°, 51° and 54°. There are two additional hour lines for the latitude 45°, for 4 a.m. and 8 p.m. The edge of the style of the gnomon is sliding and can be adjusted for the above mentioned latitudes. The compass, fixed to the following leaf, can be seen at the centre of the dial. In the space below the hour lines is a foliage decoration. The other side of the plate in the main box is engraved with a list of 32 cities and latitudes. On the sides of the box are the signature and date. The LOWER LEAF is hinged on the opposite edge of the main box as the first leaf. The INSIDE has a compass, with the cardinal points indicated. Around the compass box is a rotating arm, moving on a scale of degrees. The cardinal points are engraved in Latin and the scale is divided in quadrants, divided to ten, subdivided to two, numbered from ten to 90 by ten, with  at the top. The space between the scale and the compass case, like the spandrel space, is filled with strapwork and foliage. The OUTSIDE of the leaf has a circular table for converting unequal hours, engraved 1 to 12 twice, and common hours engraved I to XII twice, with dots indicating the half hours. The horizon line is marked with inscriptions. The symbols of the zodiac signs are engraved along a vertical line with non-linear divisions. The volvelle and the arm are missing. The spandrel area is filled with the same style of strapwork and foliage.
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