Hemisferium Miniature Astronomical Ring Dial

The Astronomical Ring Dial is a replica modelled from an early instrument created by Dutch mathematician and cartographer, Reiner Gemma Frisius, in the 16th Century. It was used by scientists and navigators to make astronomic measurements and determine the time during the day or at night.

Several different kinds of astronomic dials existed, and the larger ones could indicate the time to the minute and for a long time were the only way to know if mechanical clocks were functioning correctly without having to rely on an astronomical observatory.

It is composed of a ring that can be adjusted to various latitudes, a meridian ring showing the latitude scale, a moveable hour ring, a central grooved bar that is marked with the months of the year and a perforated cylinder, which moves through the bar. Once set up properly, it will indicate the local solar time.

Although known as the astronomical ring, it is principally employed as an equatorial solar universal quadrant. It was very popular in the Renaissance period and is regaining its popularity today amongst collectors whether they use it as a stunning decorative piece or as a functioning scientific instrument.

The ring dial measures 130mm in height, 45mm across and 4mm thick and comes on an elegant wooden stand.

Material: Zamak with brass lacquer. Sapele wood base tainted with natural wax and polished.