Diptych Sundial, Paris, Circa 1620-1630.

Oval polychrome ivory diptych sundial, Paris, circa 1620-1630. Ivory, brass, steel and glass, red, blue, gold and silver paint; 7 x 5.5 x 1.8 cm. Item #5273. A very fine example of a Parisian-made sundial from the first half of the 17th century. This diptych, or horizontal sundial with a wire axis, consists of two painted and engraved faces. The inner upper plate of the dial has a hollowed oval containing the latitude scale from 40 to 50 degrees (now the wire axis gnomon) and the names and latitudes of twelve cities, eleven French and one Italian (Naples), representing the latitudes of Paris and southern France, up to the latitude of Marseille and Naples. The background is painted a deep blue, and the cities and their latitudes are calligraphed in gold ink. Around the edge, a red background is decorated with plants in silver ink. The lower inner section is a horizontal sundial with a compass and gold-painted compass rose, a pointer and its glass, and a movable brass hour disc at the bottom. In the center, there is a compass painted in blue and gold, surrounded by a celestial scene depicting clouds, a moon, and a smiling sun. Finally, on the outer part of the dial, a brass lunar volvelle reveals the different phases of the moon. The two outer faces are blank. The two plates are joined by brass hooks. There is a small chip in the paint on the dial plate, but it is nevertheless in very fine and rare condition. For a fairly similar example but of octagonal shape, see the example in the Louvre (reference OA10148) or for an oval example in poor condition, see another example in the Louvre (reference OA11990).