細節
A LATE 16TH-CENTURY GERMAN IVORY AND GILT BRASS DIPTYCH DIAL
signed with the maker's punch mark for Hans Tucher, dedicated and dated by CH [Christian Heiden], 1571
On the inner side of the lid is a silver plaque dedicating the dial to the Holy Roman Emperor, Maximilian II, who reigned from 1564 to 1576. The last line is inscribed 'DD D S ERG CH MCLXXI'. This may be interpreted as 'dono dedit devoti servitutis ergo Christian Heiden' [given on account of his devoted service]. Below the plaque is an enamelled roundel with the arms of the Emperor.
On the top of the lid is a large gilt disc inscribed with the months, Holy days of the Church, the Zodiac, surmounted with both a solar volvelle and a lunar volvelle for finding the phase of the Moon. The latter has a lunar phase aperture, and a diagram of the planetary aspects. Two small discs are marked out with a table of Dominical Letters, beginning with the year 1569, and a perpetual calendar for the date of Easter.
When the lid is opened and set vertically, there is revealed a vertical dial and a horizontal dial for the latitude 50, both read by a string gnomon stretching between the two faces. On the horizontal face is a pin-gnomon dial for recording Italian hours. In addition, a large magnetic compass (4.6 cm. diam.) is embedded in the ivory, with the needle above a grid known as the organum Ptolemei. This is a device for reckoning time from solar altitude in equinoctial hours.
The underside of this dial is plain, except for a maker's mark, a crowned spotted snake, stamped three times; the mark is that of the Tucher family (see Gouk, op. cit., fig. 104, mark 1). Two similar dials are known, although dedicated to others, and both are dated 1569. One is in the Science Museum, London, the other in the Museum of the History of Science, Oxford. The present dial is noticed by Ernst Zinner.
4 in. (10 cm.) x 3.1/3 in. (8.1 cm.)
出版
P. Gouk, The Ivory Sundials of Nuremberg 1500-1700, Cambridge: Whipple Museum, 1988, pp. 57, 104 and 117.
E. Zinner, Deutsche und niederlndische astronomische Instrumente des 11.-18. Jahrhunderts, Munich, 1956, p. 371.