Astrolabe Glossary and Notes


A gazetteer is a list of cities along with their longitude and latitude. Frequently, the maker has added one, two or three additional geographical parameters: the inclination of the azimuth of the Qibla (the انحراف or "inḥirāf"), the direction of the azimuth of the Qibla in relation to the four cardinal points of the comapss (الجهات or "al-jihat"), and less frequently the distance from Mecca (المسافت "al-masāfat"). Gazetteers are most commonly engraved as concentric circles into the womb of Islamic astrolabes. There are, however, instruments that have additional gazetteers on the edge of the limb and on plates.

Although the order varies, all gazetteers begin with either the longitude (طول) or the latitude (عرض), given in degrees and minutes. If the maker chose to include the inḥirāf, this is usually presented next, again listed in degrees and minutes. The fourth common parameter is the jihat, which expresses the direction of the azimuth of the Qibla as northeast (abbreviated شش), southeast (abbreviated شج), southwest (abbreviated غج), south of the Qibla (abbreviated جق) or north of the Qibla (abbreviated شق).

The gazetteers in the collection have been transcribed faithfully reproducing the Arabic orthography. This will regularly reflect regional spelling variations. In translating the city names, however, we have tried to adopt a standard, recognizable spelling. Two primary reference tools have been used to assist in identifying cities: the list of cities included in Gibbs and Saliba (1984) and Kennedy and Kennedy (1987). The second of these two works is the definitive guide to Arabic place names and itself draws on Gibbs and Saliba (1984). Transcribing Arabic numbers presents a number of difficulties. In particular, certain Arabic numbers are easily confused, e.g., numbers between 11 and 19 are easily misread as numbers between 31 and 39 or numbers between 51 and 59. Where possible, the geographical parameters have been checked against the two resources cited above to see if they are reasonable. In cases of great discrepancy between the value read on the instrument and that found in printed catalogues, the instrument has been double-checked to ensure accuracy. Unusual or seeming aberrant values have not been discarded merely on the basis of their being unusual.

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