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Inventory no. 38624 - Epact entry

Epact number: 85176

Globe Dial

Unsigned
16th century; German ?
Gilt brass; 52 mm in diameter

Main text

This sundial consists of a globe on a tripod stand decorated with geometrical motifs.

The globe is set up with the hour ring in the plane of the equator. When in use, the globe is put with the 6 to VI diameter in the plane of the meridian. As the sun shines on the globe, one half is always in the shadow, and the edge of the shadow, as it moves round the hour ring, gives the time.

If the globe is turned on its axis so that the 12 to XII diameter is in the meridian, the shadow of the gnomon at noon gives the sun's declination.



Source museum: Museum of the History of Science, Oxford
Museum number: Inventory no. 38,624



Detailed text

The instrument consists of a globe standing on a tripod stand decorated with geometrical motifs. The globe is set up with the hour ring in the plane of the equator. It has the indication of the Arctic and Antarctic circles 'CIRCVLVS · ARCTICVS' and 'CIRCVLVS · ANTARCTICVS', and of the equator line 'AEQV ATOR'. Above and below the equator line are common hour lines numbered respectively I to XII, I to XII and 1 to 12, 1 to 12. The declination of the sun is indicated by the symbols of the zodiacal signs.

When in use, the globe is put with the 6 to VI diameter in the plane of the meridian. As the sun shines on the globe, one half is always in the shadow, and the edge of the shadow, as it moves round the hour ring, gives the time. If the globe is turned on its axis so that the 12 to XII diameter is in the meridian, the shadow of the gnomon at noon gives the sun's declination.

Ilaria Meliconi

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