Accession No
1680
Brief Description
ivory diptych dial, by Thomas Tucher, German, first half 17th Century
Origin
Germany; Nuremberg (Nürnberg)
Maker
Tucher, Thomas
Class
dials
Earliest Date
1600
Latest Date
1650
Inscription Date
Material
ivory; metal (brass, gilt brass); rope (string)
Dimensions
(closed) width 77mm, depth 120mm, height 11mm
Special Collection
Holden-White collection
Provenance
On loan from The Fitzwilliam Museum, University of Cambridge. Donated by Charles Holden-White to the Fitzwilliam Museum. C. Holden-White collection no. 1935-34.
Inscription
Description Notes
Rectangular ivory diptych dial with brass fittings.
Leaf Ia: lunar volvelle with gilt-brass volvelle disc with index and lunar phase diagram, marked ‘NEU MAN’, ‘ERST VIRTEL’, ‘VOL MON’, ‘LETZT VIRTEL’. Table of epacts marked ‘EPAGTA GREGORI’ and’EPAGTA IVLIANA’ starting in 1602, 1621 or 1640 (titles transposed). Leaf decorated with linear leaf pattern border and winged putti heads in corners.
Leaf Ib: pin gnomon dial for day length marked ‘QVANTIDAS DIEI’, divided 8 - 16, numbered by 1 and marked by zodiac symbol. Pin gnomon dial for Italian hours, marked ‘WELSCH VHR’, divided 13 - 24, numbered by 1. Vertical string gnomon dial for 49˚ N, divided VI - XII, I - VI, numbered by I, subdivided to 15 minutes. Representation of sun and vignette of reclining putto, left arm holding time glass on left knee, right elbow on skull. Decorative foliage.
Leaf IIa: horizontal dial for latitude 49˚ N, divided 4 - 12, 1 - 8, numbered by 1, subdivided to 15 minutes. Inset silver hour ring divided 6 - 12, 1 - 6, numbered by 1. Inset compass with cardinal points marked; meridian line offset 5˚ E for magnetic variation; bar to carry wind vane (glass and needle missing). 32-point rose around compass bowl with 16 points named. Bottom left has pin-gnomon dial for Italian hours, marked ‘WELSCH VHR’, divided 10 - 23, numbered by 1. Bottom right has pin-gnomon dial for Babylonian hours, marked ‘GROS VHR’, divided 1 - 14, numbered by 1. Maker’s mark (serpent) in compass bowl.
Leaf IIb: four brass feet; linear leaf pattern border; winged putti heads in corners; volvelle for length of day with outer
scale divided 8 - 24, numbered by 1, subdivided to 15 minutes; segments for day lengths marked ‘TAGLENG’, divided 8 - 16, numbered by 1. Gilt-brass volvelle disc divided 1 - 12, 1 - 12, numbered by 1.
Suspension ring and compartment for wind vane.
References
Events
Description
The Diptych dial is a common form of portable multi-function sundial. Diptych dials were made popular by the instrument makers in Nuremberg during the sixteenth and seventeenth centuries. They are usually made of ivory with brass fittings, and are often elaborately decorated. The name of the device derives from the Greek diptychos for a pair of folding writing tablets, which the instrument resembles.
Diptych dials consist of two leaves hinged together, with a string ‘gnomon’ stretched between the inner surfaces of the leaves for casting a shadow. To use the device as a sundial the lower leaf must be placed parallel to the horizon and the upper leaf must be at a right angle vertically to it. The gnomon must then be aligned with the meridian of the place where it is being used by using the inbuilt magnetic compass. Time can then be read from the horizontal or vertical dial by the location of the shadow cast by the string gnomon.
In addition to the horizontal and vertical dials, diptych dials normally carry a number of other features, such as equinoctial dials, windroses, tables of latitude for adjusting the string gnomon for different locations, epact tables, lunar volvelles for telling time at night by the moon, and various pin-gnomon dials for telling the time according to Babylonian or Italian hours, or for calculating the position of the Sun in the zodiac.
27/05/2009
Created by: Joshua Nall on 27/05/2009
FM:39779
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