Book excerpt: First Published in 1999. Man has always tried to find effective ways to predict the weather. Simple predictions from meteorological phenomena or from the constellations rising in the sky can be found attributed to Aristotle, and in Varro, Pliny, Ptolemy, and the parapêgmata of Classical times. However, the particular cultural situation of Baghdad in the mid-ninth century encouraged the production of what can be regarded as the first scientific treatises on weather forecasting. These are two 'letters' of the 'Philosopher of the Arabs', Ya'qüb ibn Ishãq al-Kindi (ca 800-ca. 870), who combines at least three traditions of weather forecasting: the native Arabic agricultural tradition, Greek Aristotelian meteorology, and scientific astrology. This volume sketches the history of weather forecasting from ancient times through to the Early Modern period, and places the two letters of al-Kindi in their historical and intellectual context. The original Arabic text of al-Kindi's letters has not been discovered, but the work is known through two Hebrew translations, and an independent Latin version, made directly from the Arabic, in which the two letters have been combined into one treatise. All these texts are edited here, together with an annotated English translation of the principal Hebrew version and a detailed commentary. This book not only adds to our knowledge concerning al-Kindi, but is also the first study devoted exclusively to medieval weather forecasting—a topic which, from the evidence of the number of texts and manuscripts, had a significant place in medieval scientific and social culture.