Dial from an astronomical instrument. Gilt clock disc, Iran (probably Isfahan), 17th century.

A large, convex copper disc cut from the flat, rectangular base plate of an astronomical clock. Three blank circular areas with holes at their centres were once covered by dials. The remaining surface is engraved with figures against a ground with flowering plants and trees (below) or clouds (above). The decorated area is gilded, and the background is ringmatted. The surviving figures, from the top, are a personification of Saturn; two angels, which originally supported the two upper dials; a seated figure making a measurement with a compass from a mariner's astrolabe, and his assitant (right); a seated figure using a planispheric astrolabe, and his assistant (left); a royal huntsman on horseback conversing with two servants on foot (right); a huntsman shooting an arrow at a fleeing lion, whose hindquarters only are visible (left); and, at the bottom, a Zodiac Man, an image copied from a Venetian print of 1493.

This large, convex copper disc was once part of a complex instrument of splendid appearance, which is presumed to have been an astronomical clock. When first published, in the Catalogue of the International Exhibition of Persian Art (Royal Academy of Arts, London, 1931, p.134, cat.no.209), the disc was referred to as 'Astronomical Instrument {part)'. Eight years later, Ralph Harari ('Metalwork After the Early Islamic Period', in Arthur Upham Pope, ed., A Survey of Persian Art from Prehistoric Times to the Present, vol.III, London and New York, 1939, pp.2518-19) described the piece as, 'A huge, convex, gilt copper dial (Pl.1404), mutilated and incomplete, but exquisitely engraved with figures in late seventeenth century style, is probably unique. It may have belonged to some great astronomical clock.' This description of its function has not been improved on. Nor has the dating, since, although other date ranges have been suggested, no evidence has been provided to support them.

In its original state, the disc must have formed part of the flat, rectangular base plate of the instrument, for the reasons set out below. Its current convex, circular shape would appear to be the result of the reworking of the base plate for another use after the instrument was dismantled. This secondary use has not been identified.

SPACES FOR DIALS

There are three blank, circular spaces within the decorated ground of the disc. These were once covered by dials. The largest (diameter 386 mm) is set slightly off-centre, towards the top of the plate, while the two smaller blank areas above this (diameters 250 and 254 mm) are not completely circular, as they suffered losses when the disc was sawn out of the rectangular plate. Elements of the background decoration are also missing along the edge of the disc for the same reason (see below). Saw marks can be seen along the edge of the disc, and a regular groove worked with a blunt tool lies close to the rim. The groove was presumably made when the craftsman traced the shape of the disc.

The three circular blank spaces now follow the overall convex profile of the disc, but this means that the profile of each space is irregularly convex, since, as already noted, even the larger of the three is off-centre. It seems most unlikely that the dials that once covered them were similarly irregular, and this is strong evidence that the original base plate was flat, and that the disc was beaten into a convex shape once it had been cut out of the base plate.

Each of the three blank spaces has a large hole at the centre, through which the dial was attached to the base plate. There are many smaller holes in the object, which may be divided into two groups. Most are original and were used to attach other parts of the instrument to the base plate; but a number around the edge appear to be screw holes added at a later date, and they are presumably to be associated with the secondary use of the object, when the disc was attached to a mount of some sort. This mount may have been painted green, since traces of a band of green paint up to two centimetres wide are found along the lower edge of the disc.

THE DECORATION

The rest of the surface of the disc is engraved with motifs reserved in a ringmatted ground, and this decorated area has been gilded. The decoration is divided by the choice of motifs and of background ornament into terrestrial and celestial zones: the lower half has a background covered with flowering plants and trees, while in the upper half the plants are mostly replaced by swirling clouds.

At the top is a representation of Saturn. He is shown as a male figure with seven arms, crowned, bearded and sitting on a throne. His arms hold seven attributes: a crown, a whisk, a hatchet, a rosary, a rat caught by its tail, a spear and a sieve. As noted by David Alexander (Furusiyya, vol. II: Catalogue, Riyadh, 1996, p.234, n.1), Saturn is shown holding the same attributes in 16th-century Persian manuscripts (e.g. Seyyed Hossein Nasr, Islamic Science. An Illustrated Study, London, 1976, p.104, pl.61; Barbara Schmitz, Islamic Manuscripts in the New York Public Library, New York, 1992, fig. 57).

In the next register down, two angels are shown in flight, as though supporting the dials that once covered the circular spaces above. Below this, in the "terrestrial" zone are two men of science, both seated, and each accompanied by an assistant. The man on the right makes a measurement with a compass from a mariner’s astrolabe, while his assistant stands ready with a squaring tool and a hatchet or hand-adze (tishah). The man on the left is making a reading with a planispheric astrolabe, while his seated assistant studies a manuscript, which presumably contained astronomical tables.

Below this again are depictions of Safavid courtly figures on horseback, both young, and both engaged in the hunt. The horseman on the left is shooting an arrow at a fleeing lion, whose hindquarters only survive. The other man, who wears a royal aigrette in his turban, is being served by two attendants on foot, one of whom carries a deer over his shoulders.

At the base of the disc is a diagram of a Zodiac Man, which relates to the belief that the different parts of the body are ruled by different signs of the zodiac: the head by Aries, the neck by Taurus, the breast by Cancer etc. Diagrams of this type were current in Europe by the later Middle Ages, and this image is based directly on one first printed in Venice in 1493. The Venetian diagram illustrated a compilation of medical texts called the Fasciculus medicinae of Johannes de Ketham (Europa und der Orient, 800-1900, Martin-Gropius-Bau, Berlin, 1989, p.678, cat.no.6/60, fig.762; Venise et l'Orient, Institut du Monde Arabe, Paris, 2006, pp.69, 316, cat.no.57).

On the copper disc, the image of the Zodiac Man has been reversed, and some of the zodiac symbols have been adapted to Islamic conventions. Kirsten Lippincott (The Story of Time, National Maritime Museum, London, 1999, p.225, cat.no.243) noted that Sagittarius has been given a tail with a dragon’s head, while the female figure representing Virgo is shown with a scythe and ears of corn, a reference to Sunbul, the Persian name for this house, which means 'ear of corn'. Only 11 of the signs are now visible, as the twelfth, Pisces, which ruled the feet, was lost when the disc was sawn from the base plate.

Four other features of the decoration should also be noted. These are two squared-off blank areas on either side of the feet of the zodiac man, and parts of two male figures, seen behind and above the two angels. In the case of the two figures, only the outline of one boot and the toe of another can be seen, as well as the lower corner of the coat. All four features are gilded but have no engraved details.

This disc was probably part of an astrological clock. It was originally flat and rectangular, and three dials covered the blank areas. The multi-armed figure at twelve o'clock represents Saturn. At nine and three o'clock, two men take readings with scientific instruments. At six o'clock is a Zodiac Man, a motif of European origin based on the idea that the signs of the zodiac ruled different parts of the body.

1577-1904