This doorstop of a book is the first half of a collection of fifteen studies, of which the second half, entitled Instruments of Mass Calculation is on the point of appearing in print. The title of this first half--The Call of the Muezzin (nicely illustrated in Jean Leon Gerome's evocative painting on the cover)--refers to the fact that the common theme is the tables of timekeeping and orientation, drawn up specifically for determining the times when the muezzin calls the faithful to prayer, and the postures to be adopted by the faithful. The sheer weight of the book conveys the massiveness of the Islamic contribution to this topic, whose mathematical sophistication is brought out clearly by David King's commentaries. His readers are now used to the personal tone and missionary zeal which tinges his presentation, from the names of the dedicatees of each part, through his complaints about computer programmes, to his genuine concern about the political state of the Islamic world. This presents a liveliness that alleviates the potential tedium in being utterly comprehensive ("I present a survey of all known examples of a category of Islamic astronomical tables..." [15]). Another help is the abundance and quality of the illustrations, both of the manuscripts concerned, and of Muslim observers, time-keepers and muezzin, from the earliest times to the mid-nineteenth century.
It is difficult to know where to start to summarise the contents of the volume. King points to gaps in the record: "the rich collections of astronomical manuscripts preserved in Iran remain virtually untouched" (19), "it is hard to find evidence of the use of the tables" (ibid.), and isolated copies may imply a lively tradition which has become completely lost (ibid.). One cannot tell whether the tables found their way to medieval Europe because "there is, alas, no survey of medieval European astronomical tables in general" (21). Here King paves the way, but it makes sense to take the Islamic evidence first, since it is likely to precede the European chronologically. He makes no claim beyond stating that "the present work should serve as a framework for controlling, classifying, and setting in context for any significant new sources" (22).
The mathematical functions are described first (25-42), and then the tables for timekeeping by the sun and the stars are described one by one. At the end of this part King includes a brief summary of "European Tables for Timekeeping" (183-90) which merely serves to indicate how little work has been done on the Western corpus of material (cf. the repetition of phrases such as "x has never been studied in any depth" (188, n. 19).
More specifically Islamic is Part II, on "tables for regulating the times of prayer," which is by far the longest part of the book. This deals with the rise of the ilm al-miqat (the science of astronomical timekeeping) and the new profession of muwaqqits (timekeepers). These drew up tables and wrote treatises for knowing the times of the five daily mandatory prayers: at sunset (for the Islamic day begins with the "previous" night), at nightfall, at daybreak, at sunrise and in the afternoon. Such tables and texts can be traced throughout the Islamic world from the ninth century through to tables published on the internet (http://prayer/al-islam.com).
At the beginning of Part II King hints at the calculations that were not based on mathematical astronomy. This "folk astronomy" he develops in Part III, "A survey of arithmetical shadow-schemes for time-reckoning." He begins this part with a comparison between folk astronomy and mathematical astronomy, and the obervation that every Muslim, whether well-educated or not, was required to observe three duties connected with astronomy: the observance of the sacred month of fasting by a strictly lunar calendar in which the beginnings of the months are determined by the first visibility of the lunar crescent; the performance of the five daily prayers at times determined by the sun's position; and the performance of various ritual obligations facing in a "sacred direction" towards the Ka'ba in Mecca (the qibla). This folk-astronomy includes the anwa', or 28 stars and constellations (lunar mansions) whose risings and settings were observed throughout the year.
Part IV shows how folk astronomy is used to determine the times of prayers, including the use of "seasonal hours" (i.e. the division of the hours of daylight and nighttime into twelve divisions which vary according to the seasons, rather than the "astronomical" division of the whole day and night into 24 divisions which do not vary throughout the year). King also refers to times at which prayers were forbidden because of the sun's increased magical influence (602). He compares regulations of Muslim prayer times with those of the Syrian Christians, and concludes that Muslims owed "at least some of their inspiration to Christian practice" (604), though there are aspects that are specifically Arabic, and even a touch of Indian influence. This part concludes with an anthology of Arabic texts (608-21).
Part V brings alive the actual day-to-day function of the muwaqqit and muezzin in Islamic society: their salaries, their working tools, their libraries, their level of learning and what exactly they did. This part is illustrated, both with a picture of the supposed library of the Ibn Tulun mosque in Cairo, and more Arabic texts.
Part VI deals with universal tables and instruments, i.e. those that can be used for any latitude, and universal solutions to problems of spherical astronomy. The variety and sophistication of these is impressive, but often they have survived in only copy.
Part VII collects together three shorter studies of which the first two are on the orientation of mosques and their ventilators. The third one (825-846) introduces a third example of the world-maps centred on Mecca that were the subject of King's previous World- Maps for Finding the Direction and Distance to Mecca (Leiden and London, 1999). This gives King the opportunity to correct some errors in this volume, and to discuss (and usually to dismiss) the criticisms of some of his reviewers.
Part VIII provides a useful comparison between practical timekeeping and other astronomical observations in Islamic mosques and Christian monasteries, which includes a substantial biography of studies on medieval Christian astronomical instruments. Finally, Part IX adds a touch of topicality by evoking, first of all, the scene in Frankfurt on 17-18 November, 2001, when a conference was held in David King's honour, and then the deeply distressing political situation of the time, by discussing a star table evidently composed for the latitude of Qandahar ("When the Night Sky over Qandahar was Lit only by Stars...").
Each of the Parts begins with a dedication to, and personal reminiscences concerning, a scholar who has influenced and inspired King, or to whom he is otherwise indebted: Ted Kennedy, Bernie Goldstein, Otto Neugebauer, Bashi Sabra, Asger Aaboe, Bayly Winder, Eleanor Sims and Ernst Grube, Franz Rosenthal, Jan Hogendijk, Harry and Christiane Kuhnel, Sonja Brentjes, Francois Charette and Benno van Dalen.
Thus, this volume of 930 pages is a story of a life as well as a presentation of material accumulated throughout that life. The present is interwoven with the past--both the past of King's youth, and the distant past of Habash, Ibn Yunus, Abu'l-'Uqul and al- Khalili, to whom the book as a whole is dedicated. Moreover, it shows how, in the Islamic world, the past and present form a continuum, and that astronomy and religion have always been interconnected.