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Inventory no. 42534 - Epact entry

Epact number: 36194

Horizontal Dial

16th century; German
Gilt copper and silver; 213 x 185 mm

Main text

This unusual sundial, where the string gnomon is supported by a silver figure, tells the time in planetary as well as ordinary hours, and has an elaborate zodiacal scale. There are also two volvelles which relate to astrology, one of which reveals which planet rules each of these planetary hours for each day of the week.

There is a great deal of lively decoration, including representations of the signs of the zodiac and allegorical representations of the sun and moon.

Source museum: Museum of the History of Science, Oxford
Museum number: Inventory no. 42,534

Detailed text

The basic dial is a horizontal string-gnomon dial, with two sets of hour-lines, one marked 4 to 8 and 4 to 8, the other with Roman numerals VI to XII to VI. The lower end of the string gnomon is secured to the plate at the centre of an elaborate emblem of the sun, the upper is tied into the end of a rod held above shoulder height by a silver figure, probably a Roman soldier with a tunic and helmet. Something formerly held in his left hand is missing. In front of the figure is an inset glazed compass, with a silvered base with 16 named points, 'NORD', 'NO:NO:OST', 'NORD OST', etc.

There are also lines for solar declination, with a zodiac scale on either side, with symbols and representations of the signs, each divided 0 to 30 by 10, subdivided to 1, numbered by 10. The meridian line indicates the length of day and night by the numbers 9 to 16, marked ''QVANTITAS DIEI' and 'QVANTITAS NOCTIS'. There are also parallel lines for planetary hours, marked 2 to 10.

To either side of the figure are two vovelles. One is a lunar volvelle and aspectarium, with a fixed scale of hours 0 to XII twice, divided to half and quarter hours, and a moveable disc with the diagram of planetary aspects, a circular aperture and a scale of hours 1 to 12 twice, subdivided to quarter and half hours. A small section of the edge of the disc at one 12 o'clock point is cut away to form an index and to reveal a scale of the age of the moon, 0 to 30, on the fixed plate beneath.

The second volvelle is a form of astrological planetary table, indicating the planets ruling the hours of the day - the planetary hours - for the different days of the week. The days with their symbols are marked on the base plate as 'DIEIS LVNAE', 'DIEIS MERCVRI', etc. The moving disc has a spiral scale of planetary hours 1 to 12, marked 'NVMERVM HORARVM PLANETARVM', within which are seven personifications of the days or planets.

The spare surface of the plate has elaborate decorative engraving, including animals, scrolls and foliage, and including allegorical representations of the sun and moon.

Modern wooden base.

Jim Bennett

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