Accession No
1679
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, steel); glass
Dimensions
length 116mm; breadth 69mm; thickness 21mm
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. 1935-33.
Inscription
‘TD’
Description Notes
Ivory diptych dial with brass fittings.
Leaf Ia: 32-point wind rose numbered 1 - 32 by 1 from East; 16 named points. Gilt brass index in form of an arrow (wind vane missing); leaf motif decoration; leaf pierced to show N point of compass.
Leaf Ib: pin gnomon dial for length of day, marked ‘TAG LENG’ and divided 8 - 12 (divided 8-16; 2-2-2000), numbered by 1; zodiac symbols marked. Three attachment points for string gnomon (missing) at 54˚, 48˚ and 42˚. Leaf and flower motif decoration. Maker’s mark (serpent).
Leaf IIa: horizontal dial with 3 scales for 54˚, 48˚ and 42˚; first and third divided 5 - 12, 1 - 7, numbered by 1; second scale divided V - XII, I - VII, numbered by I (but with some half hours marked (?); 2-2-2000). Inset compass with cardinal points marked and fleur-de-lys for North; offset 5˚E of North for magnetic variation; replacement needle. Concave bowl containing pin gnomon scaphe dial for Italian hours, marked ‘P 45 G’ and divided 9 - 23, numbered by 1; marked ‘WELSCH VHR’. Leaf decoration at corners of leaf.
Leaf IIb: lunar volvelle with brass disc with index. Table of epachts marked ‘EPACTA GREGORI’ and ‘EPAGTA IVLIANA’ for the years 1602-20 or 1621-39 or 1640-59. Foliage decoration.
Compartment with brass cover in side of lower leaf for storing wind vane.
Condition: fair; incomplete (string gnomon, wind vane missing).
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:43266
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