Mechanical Sundial, Late 18th Century

Universal brass minute sundial, possibly German, dating from the late 18th century. Brass, steel; the base measures 11.7 x 11.7 cm; the dial is 11 cm in diameter. This is an interesting mechanical minute sundial of German or Northern European origin, based on French models from the mid-18th century. On a square base, a circular dial is engraved with a minute scale divided from 0 to 60 and an hour scale divided into two sections from 1 to 12. Two hands indicate the hour and minute. The dial, equipped with a small mechanism, is activated by a crank located on the side. Its height is adjustable according to the arc of latitudes, divided from 0 to 90 degrees. In the center of the dial is an alidade. Once the dial is positioned at the correct latitude, the central alidade must be aligned with the sun. When the alignment is perfect, that is, when the sun's rays pass perfectly straight through the alidade, the dial shows the correct time. The engraving on the hour dial and the latitude arm is very fine; the hour and minute hands are beautifully cut. The square plate incorporates a compass and is mounted on two small leveling screws. Although unsigned, this is a rare model.