This instrument, which encompasses a horizontal sundial and compass was used for determining the prayer times and finding the qibla, the direction towards Mecca. The base of the instrument is a rectangular brass plate divided into two equal halves along the long side. The left side is again divided into two halves where the upper half contains an inscription and numerical table in abjad numerals for the determination of the times of the daylight prayers. The lower half contains a sundial with markings for Babylonian hours since sunrise. Just below the gnomon of the sundial, there is set a small compass for orienting the instrument. In the lower left corner there is a quadrant with a pivoted pointer to indicating the direction of the qibla. On the right half of the instrument there are concentric arcs of circles with radii 1-32 units, for determining the prayer time from the shadow cast by the collapsible gnomon which is located at the center of the circles. There is an third collapsible triangular gnomon located at the center of the instrument between the sundial on the left and the diagram with concentric circles on the right half. SIMILAR INSTRUMENTS Although instruments with only the sundial and qibla quadrant with pivoted pointer are more common, instruments with extra engraved tables and gazetteers seem to be less common. There are only three instruments known to literature, which have a similar make. The first is in the collection of the Oxford Museum for the History of Science ( Inv. No. 48472). This instrument is rectangular but engraved to be used vertically. The upper half is furnished with a sundial with markings for both Babylonian hours and concentric circles for measuring shadows for the determination of prayer times. There is also a hole which must have been for the inset magnetic compass. This particular instrument also misses the qibla quadrant, which is replaced with a compass diagram where each quadrant is divided from 0- 90 degrees and on which various compass directions, including Qibla. The instrument also contains a table with inhiraf for 59 localities. The second instrument, is reported to be in a private collection in Paris. The third instrument in the al-Khalili Collection is very similar in make to our instrument. It has a similar landscape position rectangular shape divided into two, with on the left side the sundial, qibla quadrant with pivoted pointer and a qibla table and markings with concentric circles on the right. The main difference seems to be the extra incomplete gazetteer on the back of the instrument. This instrument was previously in the collection of the now dispersed collection of the former Time Museum in Rockfort and was auctioned at Sotheby’s in 2004. THE MAKER The maker’s name is inscribed in a cartouche in the lower left corner of the sundial Muhammad Ibn Zakarriya. PROVENANCE Private collection, Germany LITERATURE David A. King, World-Maps for Finding the Direction and Distance to Mecca, Brill, Leiden. Pp. 118-119, 177, 281, 282, 296, 413, 439. App. 518-519. Emilie Savage-Smith, Science, Tools & Magic, The Nour Foundation in association with Azimuth Editions and Oxford University Press, Oxford, 1997 Mayer, Islamic Astrolabists, pp. 23-26, supplement. p.8 [printed in Aus der Welt der Islamischen Kunst, Gebrüder Mann, Berlin, 1959. pp. 293-296; reprinted in Fuat Sezgin, Islamic Astronomy and Mathematics, vol. 96. pp. 141-285, 291-294. Sotheby’s, Masterpieces of the Time Museum, 3 vols, London, 2004 Condition Report Condition reports and high resolution pictures are available on our website at www.orientalartauctions.com If you have any questions, feel free to contact us at [email protected]