Articles by Hamid Bohloul
Manuscript Cultures, 2024
This paper explores how an interest in mathematics and alphanumerical relations led to a vision o... more This paper explores how an interest in mathematics and alphanumerical relations led to a vision of the unity of knowledge as reflected in the Numerical Riddle by the 17th-century Safavid Iranian scholar and statesman, Mīrzā Ibrāhīm, also known as the Vizier of Azerbaijan. It also examines how this perspective was coupled with an openness to foreign sciences, exemplified by his support for the construction of a church in Tabriz for the Capuchin Fathers and missionaries where he and his son could learn from them.
Literary Snippets: A Colophon Reader, 2024
This paper aims to offer the edited text of five colophons in Arabic and Persian treatises on the... more This paper aims to offer the edited text of five colophons in Arabic and Persian treatises on the mathematical sciences, coupled with their English translations and a brief introduction of their content and the contexts in which they appeared. These colophons, discussed in chronological order, are selected because they serve as an independent historical source, encompassing one or more valuable pieces of information about the author, the scribe, their motivations, intentions, addressees, location, times, the main text, and its history, as well as the social circumstances in which the text was copied. The first colophon seems to be written by a native Arabic speaker, pointing out the grammatical inaccuracies in the holograph copy of Kūshyār ibn Labbān’s Zīj aljāmi ʿ—a common occurrence in the works of non-Arab authors. In the second colophon, the drawing of the geometrical diagrams in the text is said to have been done by the scribe himself, an information rarely provided. Such data is crucial for understanding the history of book production within Islamicate societies. The third colophon offers the name of the translator of the text, Euclid’s Phaenomena into Arabic, and the client of the translation, as well as significant information about the history of the text. By the content of this colophon and a ninth-century treatise by Ḥunayn ibn Isḥāq, it comes to light that the book was translated from Syriac, rather than Greek, into Arabic—a fact that would not have been easily uncovered otherwise. The fourth colophon is striking due to the lack of religious formula, an extremely rare, if not unique, phenomenon. The absence of these conventional religious statements signals, among other things, that the scribe was an Iranian Zoroastrian. The scribe of the fifth colophon furnishes us with an eyewitness report on the dire situation in Tehran and its outskirts amidst a cholera pandemic.
Literary Snippets, 2023
The following is a collaborative article by Sonja Brentjes and Hamid Bohloul:
In this paper, w... more The following is a collaborative article by Sonja Brentjes and Hamid Bohloul:
In this paper, we trace colophons in Arabic and Persian treatises on the mathematical and related sciences from the tenth to the nineteenth century across Islamicate societies in Asia and Africa. We ask whether there are specific features that characterize them in those disciplines in dependence on the time, the locality or the languages in which they were either produced or copied and whether there are recognizable trends that demarcate periods of change and set geographical, political or cultural boundaries. Our answers will be preliminary and limited, because such questions presuppose the systematic collection of a huge range of data and their digital investigation. Although we have collected colophons over the years and have digital access to various manuscript collections, our material was not assembled with the direct aim of writing a history of colophons in the mathematical and related sciences. We assembled colophons, because we collected texts on specific subject matters such as Euclid’s Elements or specific times and regions such as the Timurid, Ottoman and Safavid Empires in the fifteenth, sixteenth and seventeenth centuries. Despite the methodological shortcomings, our random set of colophons allows a number of observations, which will be helpful for a more systematic approach to the questions of which kind of information was stored in colophons and thus was considered desirable, useful or even necessary in different contexts. We report our results in eight sections. Section 1 highlights the advantages that a systematic, large-scale investigation of colophons can yield. Section 2 surveys information about the time of emergence of colophons in treatises on the mathematical and related sciences. Section 3 lists the religious elements of colophons. Section 4 presents the main types of colophons found in texts from the mathematical and related sciences. Section 5 discusses socio-cultural components. Section 6 focuses on statements on the history of the treatise provided in colophons. Section 7 describes the formal configurations and placements of colophons. Section 8 presents a few exceptional colophons. At the end, we offer some preliminary conclusions about what colophons can contribute to the history of mathematical and related science in Islamicate societies. The term mathematical and related sciences is used in this paper to encompass the range of disciplinary fields that historical actors counted among the mathematical sciences, including different forms of geography and mapmaking.
Intellectual History of the Islamicate World, 2023
In this paper we discuss a number of copies of ʿAbd al-Raḥmān al-Ṣūfī's Book on the Star Constell... more In this paper we discuss a number of copies of ʿAbd al-Raḥmān al-Ṣūfī's Book on the Star Constellations with the aim to elucidate which of them can be justifiably called "patronage object" and which properties they share. We argue that such an object is always a material, not merely an intellectual product. Thus, the analysis of the patronage status of a scientific work needs to go beyond its scholarly content and narrative performance and include features of execution, purpose and addressee of copying and acts of re-appropriating the work on its various scholarly, cultural and political levels. We present a few examples to demonstrate the usefulness of such a holistic approach to the question of what is a patronage object in the mathematical sciences. Keywords ʿAbd al-Raḥmān al-Ṣūfī-Book on the Star Constellations-patronage This paper addresses two seemingly simple questions, namely what is a patronage object and what properties mark such an object in the mathematical
The Moon: A Voyage Through Time, Aga Khan Museum, 2019
Scholars in Islamic societies discussed the moon, its orbit, size, light, and impact on earth in ... more Scholars in Islamic societies discussed the moon, its orbit, size, light, and impact on earth in a range of different fields of knowledge, some of which we consider scientific still today, while others have become fields outside academia. The most important disciplinary domains in which the moon was discussed as an object of inquiry were, from a modern perspective, astronomy, astrology, medicine, natural philosophy, optics, alchemy, and agronomy. In past centuries in Islamic lands, there were three kinds of official designations for people who studied the heavens with mathematical tools: calculators and astrologers (since the eighth century) and timekeepers (since the thirteenth century).
Astronomy provided tables of latitudes and longitudes of the moon, lunar mean motions, or lunar mansions; offered new models of the lunar orbit; and explained and visualized lunar phases and eclipses in often colourful diagrams. Lunar astrology depended on the knowledge of the moon and its path through specific groups of stars called lunar mansions or stations. On this basis, astrologers determined the birth horoscope and character, physiognomy, and future of a girl or a boy. They could also specify with this kind of information the natural or political future of an empire or a city or predict rain, winds, floods, and periods of heat, cold, or dryness. Eclipses were threatening social events that needed special prayers and decisive measures of the rulers to calm the population. Scholars also studied eclipses in the field of optics to better understand vision, light, and colour.
Natural philosophy discussed the coming into being of the universe and its components. The sphere of the moon separates the celestial from the terrestrial realm and the elements. Earthquakes, rainbows, tides, conception, gestation of the fetus, and birth were all discussed with respect to the moon and its movements.
In the religious realm, the first visibility of the crescent after the conjunction of the sun and the moon was and is of great importance for Muslims, in particular at the beginning of Ramadan. Astrologers and timekeepers tried to calculate the rise of the moon over the horizon and debated the factors that conditioned or impeded its visibility. For their part, religious scholars often considered such methods insufficient and insisted on human sighting of the moon to determine particular holidays and rituals.
Scientific Instruments between East and West, Brill, 2019
Ghīyāth al-Dīn Jamshīd ibn Mas‘ūd ibn Maḥmūd ibn Muḥammad Kāshānī (or al-Kāshī), the fifteenth-ce... more Ghīyāth al-Dīn Jamshīd ibn Mas‘ūd ibn Maḥmūd ibn Muḥammad Kāshānī (or al-Kāshī), the fifteenth-century Iranian astronomer and mathematician, is known nowadays for his precise calculation of π and Sin 1°, and for his contribution to Ulugh Beg’s observatory at Samarkand. In 818 H (1416 CE), most probably in his home town of Kāshān, he invented an equatorium, and wrote an Arabic treatise on its construction and use. The treatise had the title Nuzhat al-Ḥadāʾiq (Excursion to the Gardens) and the equatorium was called Ṭabaq al-Manāṭiq (Plate of the Deferents). In the Nuzha, he also described another instrument, named Lawḥ al-Ittiṣālāt (Plate of Conjunctions). The main purpose of both instruments was to reduce the amount of calculation astrologers needed to do. About ten years later, while Kāshānī was working at Samarkand Observatory, he wrote an Arabic supplementary tract to the Nuzha, in which he added a set of ten appendices. Most of them describe new methods of construction and give simple and more precise instructions for using the equatorium.
During the reign of Sultan Bayezid II (from 1481 to 1512), most probably in Istanbul, an anonymous astronomer composed an untitled Persian treatise about Kāshānī’s equatorium, and dedicated it to the Sultan. Having found the only manuscript of this Persian treatise, the late Edward S. Kennedy surmised that the original work of Kāshānī was lost. He started his investigation of the equatorium using the Persian text and published two papers, one on the Plate of Conjunctions in 1947, and the other on the equatorium in 1950. In 1951 he discovered that a manuscript of Kāshānī’s Nuzha was preserved in the India Office Library in London, but he carried on his research without paying much attention to this original work of Kāshānī. The result was two more papers in the same year, 1951. It was only in his last paper in 1952 that he included some information about the original Arabic text. Eventually, in 1960 he published a book on the instrument entitled The Planetary Equatorium of Jamshīd Ghīyāth al-Dīn al-Kāshī, which included a facsimile of the Persian text, an English translation and a commentary. Kennedy also discussed briefly some of the appendices Kāshānī published in the supplementary tract.
As nearly all of Kennedy’s contribution is based on the Persian treatise of the anonymous Ottoman astronomer, it is worth studying Kāshānī’s own text to learn more about his equatorium and his scientific career. In the present chapter I describe some of the features of the original text and explain how the three additional plates described in the Nuzha can be used to find the true longitudes of the superior planets (Mars, Jupiter and Saturn) and of Venus. I also show how the equatorium can be used for different geographical longitudes.
دایرة المعارف بزرگ اسلامی، ج 22 / Great Encyclopedia of Islam, 2016
خُجندی، ابو محمود حامد بن خضر، منجم، ریاضیدان و ابزارساز برجستۀ قرن چهارم. او را ابومحمد نیز گفت... more خُجندی، ابو محمود حامد بن خضر، منجم، ریاضیدان و ابزارساز برجستۀ قرن چهارم. او را ابومحمد نیز گفتهاند. مورخان و تذکره نویسان متقدم به زندگی و احوال او نپرداختهاند؛ ولی قراین تاریخی گواه فعالیت علمی او در نیمۀ دوم قرن چهارم در ری است. ابوجعفر خازن، در رسالهای، اثبات قضیهای در ریاضیات را به خجندی نسبت داده و آن را ناقص و غلط دانسته است. فارغ از موضوع مسأله، ادعای ابوجعفر خازن قدیمیترین نشانه دربارۀ خجندی است. درگذشت ابوجعفر خازن را میان 350ق و 360ق گفتهاند؛ اگر رسالۀ مذکور را مربوط به اواخر زندگی خازن و اثبات خجندی را مربوط به دورۀ جوانیش بدانیم، پس باید تولد خجندی را 340ق و یا پیش از آن فرض کنیم. محل تولد او نیز روشن نیست؛ اما از نسبتش به خجند میتوان گفت که خود یا اجدادش برخاسته از آن دیار بودهاند. او در 384ق بیشینۀ میل دایرةالبروج («میل کلی») و عرض جغرافیایی ری را اندازهگیری کرده است و پس از آن مشغول رصد سیارات برای تدوین زیجی به نام «زیج فخری» بوده است؛ اما احتمالاً تدوین این زیج ناتمام مانده است (نک: دنبالۀ مقاله). از آن سال به بعد دیگر اطلاعی از فعالیتهای او در دست نیست. از این رو، سوتر درگذشت او را حدود 390ق دانسته است.
دانشنامۀ ایران، ج 4 / The Encyclopedia of Iran, 2015
اقبال و ادبار، دیدگاهی در نجوم کهن که بر پایۀ آن، حرکت نقاط اعتدال بر دایرة البروج، حرکتی نوسانی ... more اقبال و ادبار، دیدگاهی در نجوم کهن که بر پایۀ آن، حرکت نقاط اعتدال بر دایرة البروج، حرکتی نوسانی با دامنۀ 8 درجه بهشمار میآمد. بیشتر منجمان میدانستند که حرکت نقاط اعتدال با سرعتی کمابیش ثابت و همواره در یک جهت است (نک هد، اعتدالین، تقدیم)، اما اقبال و ادبار از روزگار هیپارخوس تا هنگامی که تیکو براهه آن را رد کرد، پیروانی داشت. پیشروی نقطۀ اعتدال بهاری از اول حمل در جهت توالی بروج تا 8 درجه اقبال و بازگشت آن به اول حمل نیز ادبار نامیده میشد. نخستین اشارۀ مکتوب به نظریۀ حرکت اقبال و ادبار را میتوان در شرح کوچک تئون اسکندرانی (ه د) بر جدولهای آسان بطلمیوس مشاهده کرد. اگرچه او این اندیشه را به «اهل احکام نجوم» نسبت داده اما پیداست که خود نیز بر این باور بوده است. به گزارش تئون این حرکت با سرعت 1 درجه در هر 80 سال در حال تناوب است. از میان منجمان دورۀ یونانیمآبی نیز تنها پروکلس به آن اشاراتی، آن هم بدون بیان جزئیات کرده است. از این واقعیت که بابلیها اعتدال بهاری را در درجۀ هشتم حمل فرض میکردند و این که تئون در توصیف آن از تابع زیگزاگی خطی استفاده کرده است، نویگباور حدس زده است که منشأ نظریۀ اقبال و ادبار باید با نجوم بابلی و نجوم دورۀ هیپارخوس پیوندهایی داشته باشد. درایر نادانی و کجفهمی بانی یا بانیان آن را عامل طرح چنین نظریۀ بیپایه و اساسی در تاریخ نجوم عنوان کرده است. کلیات این نظریه با واسطههایی نامشخص به نجوم هندی رسید و با تغییراتی (مثلاً افزایش بازۀ جابهجایی نقاط اعتدال از8 درجه به 54 درجه) به یکی از مفاهیم بنیادی آن تبدیل شد. در دورۀ اسلامی نیز اگرچه اغلب منجمان از پذیرش این نظریه امتناع کردند؛ اما منجمان حاذق و کارآزمودهای چون حبش حاسب مروزی، ابراهیم بن سنان، ابن آدمی، ابوجعفر خازن، قاضی صاعد اندلسی، زرقالی و ابن هائم، آن را یا عیناً، یا با اندکی جرح و تعدیل و یا با عرضۀ الگوهایی پیچیدهتر پذیرفتند. در میان منجمان اخیر، زرقالی سه الگوی متفاوت برای حرکت اقبال و ادبار پیشنهاد کرد؛ کارهای او اوج فعالیتهای منجمان دورۀ اسلامی در این زمینه را نشان میدهد.
کتاب ماه علوم و فنون, 2011
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دایرةالمعارف بزرگ اسلامی، جلد 19 / Great Encyclopedia of Islam, 2011
جَيْبْ
تابعی ریاضی، تقریباً معادل تابع سینوس در مثلثات امروزی و مهمترین تابع مثلثاتی نجوم در دو... more جَيْبْ
تابعی ریاضی، تقریباً معادل تابع سینوس در مثلثات امروزی و مهمترین تابع مثلثاتی نجوم در دورۀ اسلامي. جَيب که امروزه آن را با
Sin
نمایش میدهند در وهلۀ اول برای کمان تعریف میشود و در ریاضیات دوره اسلامی دو تعریف معادل داشته است: الف- نيمي از وترِ دو برابرِ هر كمان ؛ ب- عمودي كه از يك طرف كمان، به قطر گذرنده از طرف ديگر كمان وارد ميشود. زیج حبش حاسب کهنترین متنی است که این تعریف در آن آمده است. برخي از رياضيدانان، مانند ابوريحان بيروني و نصیرالدین طوسی، هر دو تعريف را يكسان دانسته و از آنها در آثار خود استفاده كردهاند. اما برخي تعريف اول را خالی از اشكال ندانستهاند، زيرا طبق این تعریف کمانهای بزرگتر از 180 درجه و کوچکتر از 360 درجه دارای جیب نخواهند بود؛ چون داراي كمان دو برابر خود نيستند. برخي نيز براي رفع اين ايراد، راهي براي محاسبۀ دو برابر كمان پيشنهاد كردهاند؛ بدين ترتيب كه هر گاه دو برابر كماني از كل دايره بزرگتر باشد، كل دايره را از آن كم ميكنيم؛ باقيمانده، معادل دو برابر كمان مورد نظر است. در ریاضیات دوران اسلامی، جَیب مستوی، جَیب راست و جَیب مبسوط معادل جَیب به کار میرفتهاند.
Astronomy and Its Instruments Before and After Galileo, 2010
The Museum of Astān Quds Razavī located in the city of Mashhad (in the northeast of Iran), was es... more The Museum of Astān Quds Razavī located in the city of Mashhad (in the northeast of Iran), was established in 1324 AH (1945 AD). The very rich collection of the museum pertains to cultural heritage of Islamic countries. The late Sayyid Jalāl al-Dīn Tehrānī gathered highly valuable astronomical instruments from all around the world. These instruments were endowed in the museum by him. After that, one of us (F. R.) prepared them for public displaying. This part of museum was inaugurated in 1375 AH (1996 AD), in the second floor of the central Museum of Astān Quds. Some of these instruments such as astrolabes, celestial globes and telescopes are here illustrated.
دایرةالمعارف بزرگ اسلامی، ج 16 / Great Encyclopedia of Islam, 2008
Thesis by Hamid Bohloul
Unpublished MA thesis, Institute for the History of Science, University of Tehran, 2008
Ptolemy’s (ca. 150 A.D.) main astronomical corpus discusses planetary distances and sizes. In the... more Ptolemy’s (ca. 150 A.D.) main astronomical corpus discusses planetary distances and sizes. In the Almagest, he derived the true distances of the moon and the sun from the Earth’s center and the relative distances of the planets according to their deferent orbs. In the Planetary Hypotheses, he adopted a philosophical and mathematical approach to measure the true distances of other planets in terms of the terrestrial radius. His assumption, based on the Aristotelian tenet that no void space occurs in nature, led him to deduce that the maximal distance of a planet coincides with the minimal distance of the one beyond it. By assuming the order of planets, he was able to establish their distances and sizes.
As expected, Ptolemy’s successors attempted to achieve more accurate results. Muʾyyad al-Dīn al-ʿUrḍī (ca. 1200-ca. 1266) criticized Ptolemy’s order of planets and the accuracy of his computations by carefully examining Ptolemy’s texts rather than relying solely on observations. His objections led to a change in the position of Venus; it was previously believed to be immediately beneath the sun, but al-ʿUrḍī stated that it should be considered a superior planet, exactly over the sun. Quṭb al-Dīn al-Shīrāzī (1236-1311), one of al-ʿUrḍī’s colleagues at the Maragha observatory, accepted these criticisms and their results without question.
Later, Ghīyāth al-Dīn Jamshīd al-Kāshī (or Kāshānī) (d. 1429) revisited the problem by writing a monograph titled Sullam al-samāʾ (Ladder towards the Heaven), which exclusively focused on planetary distances and sizes. In his work, he approved most of al-ʿUrḍī’s remarks, although he strongly opposed the new order of planets. The core of al-Kāshī’s argument was based on a more precise computation of lunar and solar distances. He repeated nearly all of Ptolemy’s steps with greater precision and eventually concluded that the established view is absolutely authentic, and thus, no alteration in the order of planets would be necessary.
My MA thesis, which is partially uploaded here, primarily focuses on al-ʿUrḍī’s criticisms and al-Kāshī’s mathematical method to assess al-ʿUrḍī’s claim. To achieve this, I have edited the Arabic text of al-Kāshī’s Sullam al-samāʾ based on ten copies and one lithograph edition and translated it into Persian. In the commentary section, I have carefully studied al-ʿUrḍī’s assertion through the hay’a works of Shīrāzī, which was likely the source of al-Kāshī, and then discussed the method used by al-Kāshī to refute the idea that Venus is a superior planet.
Unpublished PhD thesis, Institute for Humanities and Cultural Studies, Tehran, 2017
Equatorium is a geometrical instrument used to find certain astronomical parameters, such as plan... more Equatorium is a geometrical instrument used to find certain astronomical parameters, such as planetary longitudes and latitudes. It is primarily considered one of the innovations of Islamicate astronomers. The main function of the equatorium is to offer a graphical solution for astronomical problems that would typically require numerical computations.
Ghīyāth al-Dīn Jamshīd Kāshānī (ca. late 14th century - 22 June 1429), the renowned Iranian mathematician and astronomer, was one of the five astronomers in the Islamicate world who designed an equatorium. In 1416 CE (818 AH), he compiled an Arabic treatise on the construction and use of his equatorium. He named the treatise Nuzhat al-ḥadā’iq (Excursion to the gardens) and the instrument Ṭabaq al-manāṭiq (Plate of deferents), respectively. After nearly a decade, in 1426, he wrote another Arabic tract comprised of ten appendices aimed at improving the instrument. Both of these works have hitherto remained unpublished.
Unfortunately, no physical specimen of Kāshānī’s equatorium has been passed down to us. Therefore, it is yet to be demonstrated whether the instrument can be constructed with the same applications claimed by its inventor or not. Moreover, neither of the extant manuscripts of this work, which I consulted, bears even a sketch of the instrument. Furthermore, Kāshānī does not provide any reasons for the authenticity of his graphical solutions, nor does he point to the underlying theories of the instrument.
In this thesis, I address the abovementioned issues. Hence, I attempted to reconstruct different forms of equatoria on the basis of the descriptions he provided, displaying the functionality of the graphical solutions through numerous new figures, and demonstrating the veracity of the provided instructions for determining planetary longitudes with the instrument, to the extent possible. These studies constitute a substantial part of the commentary that follows my critical editions and Persian translations of the two Arabic treatises. These materials are preceded by my introduction, which concerns Kāshānī’s intellectual career prior to his relocation to Samarqand.
Drafts by Hamid Bohloul
Jour for Intellectual History in the Islamicate World, 2022
This paper has been published by now online, but is not allowed tobe uploaded here. Hence, I chos... more This paper has been published by now online, but is not allowed tobe uploaded here. Hence, I chose a version from the stage of correction.
Reviews by Hamid Bohloul
Journal for the History of Astronomy, 2023
Book Review: al-Kharaqī’s Muntahá al-idrāk fī taqāsīm al-aflāk (The Utmost Attainment on the Divi... more Book Review: al-Kharaqī’s Muntahá al-idrāk fī taqāsīm al-aflāk (The Utmost Attainment on the Divisions of the Orbs):
The First Comprehensive Hayʾa Work on Ptolemaic Cosmology. Hanif Ghalandari (Miras-e Maktoob,
Tehran, 2020). Pp. 184 + 696 + 20. $37. ISBN 9786002031907 (paper).
Abū Muḥammad ʿAbd al-Jabbār al-Kharaqī (1084–1158) was revered as a scholar of ḥadīth and Islamic law in the eyes of his contemporaries. However, his scholarly contributions went beyond these fields, encompassing treatises on hayʾa, magic squares, logic, and local history. Although the latter two works, along with several other writings attributed to him by Islamicate bibliographers, have not survived to the present era, he has garnered prominence for his notable trio of hayʾa works, particularly his Muntahá which exerted a significant influence on the evolution of hayʾa literature. Defining the term hayʾa, which literally means “shape” but is usually translated as “configuration” in the context of astronomy, is challenging because it is ascribed to a cluster of astronomical works whose characteristics are not always entirely identical. However, with caution, it might be suggested that these works sought to present a non-technical overview of Ptolemy’s Almagest. Since the second half of the 10th century and in the decades following, the majority of hayʾa writers began modifying Ptolemaic planetary models by considering the physical existence of the celestial spheres. al-Kharaqī’s Muntahá is one of the earliest works to follow this novel trend.
Journal for the History of Astronomy, 2019
Astrolabes in Medieval Cultures. Josefina Rodríguez-Arribas, Charles Burnett, Silke Ackermann and... more Astrolabes in Medieval Cultures. Josefina Rodríguez-Arribas, Charles Burnett, Silke Ackermann and Ryan Szpiech (Brill, Leiden, 2019). Pp. vi + 508. € 87. ISBN 9789004383807 (paper).
The volume is composed of 15 papers totally or partially relevant to the astrolabe. Eight of the papers were formerly presented in a conference in April, 2014 held at the Warburg Institute, University of London. The entire set, except the last one, appeared in 2017 as a special issue of the journal Medieval Encounters 23.1-5. Now a slightly revised and updated version of the papers, plus to an epilogue, appear in this book.
More than any other ancient or medieval scientific instrument, the astrolabe, over the past 150 years, has drawn the attention of modern scholars who have attempted to shed light on the mathematical, astronomical, practical and pedagogical aspects of the instrument that appropriately reflects the sophisticated level of medieval science and craftsmanship. Nevertheless, there are still numerous texts and surviving specimens of artefact that deserve further attention. This volume, therefore, aims to fill a certain number of gaps by addressing several unpublished and unstudied texts and examining some physical astrolabes.
Iranian History of Science Newsletter, 2011
Published by the Institute for History of Science, University of Tehran, Tarikh-e Elm is an Irani... more Published by the Institute for History of Science, University of Tehran, Tarikh-e Elm is an Iranian journal founded in 2003 by Prof. Hadi „Alem-Zadeh, the then institute director. The Tarikh-e Elm is the first journal wholly dedicated to the history of science in Iran, although before the journal was established, other Iranian journals such as Tahghighat-e Islami, Farhang, Mirath-e Javidan, had published special issues in this field. Prof. Hadi „Alem-Zadeh was the editor-in-chief for the first five issues. Having retired, he was succeeded by Dr. Mohammad Bagheri since.
The journal, as its editor-in-chief announced in the sixth issue, aims “to acquaint those who are interested in the scientific heritage of Iran and other parts of the Islamic world with scientific researches in this field, to inform them of events in the history of science taking place in Iran, and to provide a context for circulation of scientific contributions in the history of exact and natural sciences from the Islamic period.” The language policy of the journal has changed over the course of its publication. In the first two issues, Persian was the only language used. However, from then on, the policy changed to include English and French. From the beginning, all abstracts of articles have been printed both in English and Persian.
Translations by Hamid Bohloul
میراث علمی اسلام و ایران، ش17, 2021
حمایت شاهان از علوم غریبه در جهان فارسی زبان در دورۀ پس از مغول به یکباره افزایش یافت و این جریان... more حمایت شاهان از علوم غریبه در جهان فارسی زبان در دورۀ پس از مغول به یکباره افزایش یافت و این جریان مقدم بر تحولات مشابه در اروپای دورۀ نوزایی بود. این حمایت به طور خاص در پی رونق گرفتن علوم غریبه در میان علمای بزرگ در قلب سرزمینهای اسلامی از میانۀ قرن هشتم هجری به بعد بود. جذابیت این علوم سبب شد تا فرمانروایان مملوک، تیموری و آققویونلو عالمان علوم غریبه را غالباً در سمتهایی چون سیاستگذار و نظریهپرداز برای پشتیبانی از دعاوی سلطنتی خود به کار گیرند. این حکومتها در قرن نهم، و سلسلههای صفوی، عثمانی و گورکانی در قرنهای آتی، سنت حمایت از علوم غریبه را که پشتوانۀ عقیدتی بسیار مهمی برایشان فراهم میکرد، ادامه دادند و در واقع، این سنت در آستانۀ هزارۀ اسلام که اوج موعودگرایی سلطنتی بود، بسط یافت.
میراث علمی اسلام و ایران، ش17, 2021
در جلد ۴۸ ، شمارۀ سوم و چهارم، مجلۀ آیسیس (ص ۳۷۴ )، نقد کوتاهی از پروفسور سارُتن بر کتابی از ای. ... more در جلد ۴۸ ، شمارۀ سوم و چهارم، مجلۀ آیسیس (ص ۳۷۴ )، نقد کوتاهی از پروفسور سارُتن بر کتابی از ای. اس. دراور، دربارۀ صابئین، با عنوان کتاب منطقةالبروج منتشر شده است. ناقد این اثر را «مجموعۀ بیارزشی از پیشگوییها، مطالب احکام نجومی بیپایه و دیگر خزعبلات» توصیف کرده است. این تعبیر در حقیقت صحیح است اما بیانگر کل ماجرا نیست، لذا بنا دارم آن را به ضمیمۀ نکاتی شرح دهم و بگویم که چرا یک محقق واقعی اتفاقًا باید سالها وقت خود را صرف مطالعۀ موضوعات بیارزشی مانند احکام نجوم قدیم کند.
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Articles by Hamid Bohloul
In this paper, we trace colophons in Arabic and Persian treatises on the mathematical and related sciences from the tenth to the nineteenth century across Islamicate societies in Asia and Africa. We ask whether there are specific features that characterize them in those disciplines in dependence on the time, the locality or the languages in which they were either produced or copied and whether there are recognizable trends that demarcate periods of change and set geographical, political or cultural boundaries. Our answers will be preliminary and limited, because such questions presuppose the systematic collection of a huge range of data and their digital investigation. Although we have collected colophons over the years and have digital access to various manuscript collections, our material was not assembled with the direct aim of writing a history of colophons in the mathematical and related sciences. We assembled colophons, because we collected texts on specific subject matters such as Euclid’s Elements or specific times and regions such as the Timurid, Ottoman and Safavid Empires in the fifteenth, sixteenth and seventeenth centuries. Despite the methodological shortcomings, our random set of colophons allows a number of observations, which will be helpful for a more systematic approach to the questions of which kind of information was stored in colophons and thus was considered desirable, useful or even necessary in different contexts. We report our results in eight sections. Section 1 highlights the advantages that a systematic, large-scale investigation of colophons can yield. Section 2 surveys information about the time of emergence of colophons in treatises on the mathematical and related sciences. Section 3 lists the religious elements of colophons. Section 4 presents the main types of colophons found in texts from the mathematical and related sciences. Section 5 discusses socio-cultural components. Section 6 focuses on statements on the history of the treatise provided in colophons. Section 7 describes the formal configurations and placements of colophons. Section 8 presents a few exceptional colophons. At the end, we offer some preliminary conclusions about what colophons can contribute to the history of mathematical and related science in Islamicate societies. The term mathematical and related sciences is used in this paper to encompass the range of disciplinary fields that historical actors counted among the mathematical sciences, including different forms of geography and mapmaking.
Astronomy provided tables of latitudes and longitudes of the moon, lunar mean motions, or lunar mansions; offered new models of the lunar orbit; and explained and visualized lunar phases and eclipses in often colourful diagrams. Lunar astrology depended on the knowledge of the moon and its path through specific groups of stars called lunar mansions or stations. On this basis, astrologers determined the birth horoscope and character, physiognomy, and future of a girl or a boy. They could also specify with this kind of information the natural or political future of an empire or a city or predict rain, winds, floods, and periods of heat, cold, or dryness. Eclipses were threatening social events that needed special prayers and decisive measures of the rulers to calm the population. Scholars also studied eclipses in the field of optics to better understand vision, light, and colour.
Natural philosophy discussed the coming into being of the universe and its components. The sphere of the moon separates the celestial from the terrestrial realm and the elements. Earthquakes, rainbows, tides, conception, gestation of the fetus, and birth were all discussed with respect to the moon and its movements.
In the religious realm, the first visibility of the crescent after the conjunction of the sun and the moon was and is of great importance for Muslims, in particular at the beginning of Ramadan. Astrologers and timekeepers tried to calculate the rise of the moon over the horizon and debated the factors that conditioned or impeded its visibility. For their part, religious scholars often considered such methods insufficient and insisted on human sighting of the moon to determine particular holidays and rituals.
During the reign of Sultan Bayezid II (from 1481 to 1512), most probably in Istanbul, an anonymous astronomer composed an untitled Persian treatise about Kāshānī’s equatorium, and dedicated it to the Sultan. Having found the only manuscript of this Persian treatise, the late Edward S. Kennedy surmised that the original work of Kāshānī was lost. He started his investigation of the equatorium using the Persian text and published two papers, one on the Plate of Conjunctions in 1947, and the other on the equatorium in 1950. In 1951 he discovered that a manuscript of Kāshānī’s Nuzha was preserved in the India Office Library in London, but he carried on his research without paying much attention to this original work of Kāshānī. The result was two more papers in the same year, 1951. It was only in his last paper in 1952 that he included some information about the original Arabic text. Eventually, in 1960 he published a book on the instrument entitled The Planetary Equatorium of Jamshīd Ghīyāth al-Dīn al-Kāshī, which included a facsimile of the Persian text, an English translation and a commentary. Kennedy also discussed briefly some of the appendices Kāshānī published in the supplementary tract.
As nearly all of Kennedy’s contribution is based on the Persian treatise of the anonymous Ottoman astronomer, it is worth studying Kāshānī’s own text to learn more about his equatorium and his scientific career. In the present chapter I describe some of the features of the original text and explain how the three additional plates described in the Nuzha can be used to find the true longitudes of the superior planets (Mars, Jupiter and Saturn) and of Venus. I also show how the equatorium can be used for different geographical longitudes.
تابعی ریاضی، تقریباً معادل تابع سینوس در مثلثات امروزی و مهمترین تابع مثلثاتی نجوم در دورۀ اسلامي. جَيب که امروزه آن را با
Sin
نمایش میدهند در وهلۀ اول برای کمان تعریف میشود و در ریاضیات دوره اسلامی دو تعریف معادل داشته است: الف- نيمي از وترِ دو برابرِ هر كمان ؛ ب- عمودي كه از يك طرف كمان، به قطر گذرنده از طرف ديگر كمان وارد ميشود. زیج حبش حاسب کهنترین متنی است که این تعریف در آن آمده است. برخي از رياضيدانان، مانند ابوريحان بيروني و نصیرالدین طوسی، هر دو تعريف را يكسان دانسته و از آنها در آثار خود استفاده كردهاند. اما برخي تعريف اول را خالی از اشكال ندانستهاند، زيرا طبق این تعریف کمانهای بزرگتر از 180 درجه و کوچکتر از 360 درجه دارای جیب نخواهند بود؛ چون داراي كمان دو برابر خود نيستند. برخي نيز براي رفع اين ايراد، راهي براي محاسبۀ دو برابر كمان پيشنهاد كردهاند؛ بدين ترتيب كه هر گاه دو برابر كماني از كل دايره بزرگتر باشد، كل دايره را از آن كم ميكنيم؛ باقيمانده، معادل دو برابر كمان مورد نظر است. در ریاضیات دوران اسلامی، جَیب مستوی، جَیب راست و جَیب مبسوط معادل جَیب به کار میرفتهاند.
Thesis by Hamid Bohloul
As expected, Ptolemy’s successors attempted to achieve more accurate results. Muʾyyad al-Dīn al-ʿUrḍī (ca. 1200-ca. 1266) criticized Ptolemy’s order of planets and the accuracy of his computations by carefully examining Ptolemy’s texts rather than relying solely on observations. His objections led to a change in the position of Venus; it was previously believed to be immediately beneath the sun, but al-ʿUrḍī stated that it should be considered a superior planet, exactly over the sun. Quṭb al-Dīn al-Shīrāzī (1236-1311), one of al-ʿUrḍī’s colleagues at the Maragha observatory, accepted these criticisms and their results without question.
Later, Ghīyāth al-Dīn Jamshīd al-Kāshī (or Kāshānī) (d. 1429) revisited the problem by writing a monograph titled Sullam al-samāʾ (Ladder towards the Heaven), which exclusively focused on planetary distances and sizes. In his work, he approved most of al-ʿUrḍī’s remarks, although he strongly opposed the new order of planets. The core of al-Kāshī’s argument was based on a more precise computation of lunar and solar distances. He repeated nearly all of Ptolemy’s steps with greater precision and eventually concluded that the established view is absolutely authentic, and thus, no alteration in the order of planets would be necessary.
My MA thesis, which is partially uploaded here, primarily focuses on al-ʿUrḍī’s criticisms and al-Kāshī’s mathematical method to assess al-ʿUrḍī’s claim. To achieve this, I have edited the Arabic text of al-Kāshī’s Sullam al-samāʾ based on ten copies and one lithograph edition and translated it into Persian. In the commentary section, I have carefully studied al-ʿUrḍī’s assertion through the hay’a works of Shīrāzī, which was likely the source of al-Kāshī, and then discussed the method used by al-Kāshī to refute the idea that Venus is a superior planet.
Ghīyāth al-Dīn Jamshīd Kāshānī (ca. late 14th century - 22 June 1429), the renowned Iranian mathematician and astronomer, was one of the five astronomers in the Islamicate world who designed an equatorium. In 1416 CE (818 AH), he compiled an Arabic treatise on the construction and use of his equatorium. He named the treatise Nuzhat al-ḥadā’iq (Excursion to the gardens) and the instrument Ṭabaq al-manāṭiq (Plate of deferents), respectively. After nearly a decade, in 1426, he wrote another Arabic tract comprised of ten appendices aimed at improving the instrument. Both of these works have hitherto remained unpublished.
Unfortunately, no physical specimen of Kāshānī’s equatorium has been passed down to us. Therefore, it is yet to be demonstrated whether the instrument can be constructed with the same applications claimed by its inventor or not. Moreover, neither of the extant manuscripts of this work, which I consulted, bears even a sketch of the instrument. Furthermore, Kāshānī does not provide any reasons for the authenticity of his graphical solutions, nor does he point to the underlying theories of the instrument.
In this thesis, I address the abovementioned issues. Hence, I attempted to reconstruct different forms of equatoria on the basis of the descriptions he provided, displaying the functionality of the graphical solutions through numerous new figures, and demonstrating the veracity of the provided instructions for determining planetary longitudes with the instrument, to the extent possible. These studies constitute a substantial part of the commentary that follows my critical editions and Persian translations of the two Arabic treatises. These materials are preceded by my introduction, which concerns Kāshānī’s intellectual career prior to his relocation to Samarqand.
Drafts by Hamid Bohloul
Reviews by Hamid Bohloul
The First Comprehensive Hayʾa Work on Ptolemaic Cosmology. Hanif Ghalandari (Miras-e Maktoob,
Tehran, 2020). Pp. 184 + 696 + 20. $37. ISBN 9786002031907 (paper).
Abū Muḥammad ʿAbd al-Jabbār al-Kharaqī (1084–1158) was revered as a scholar of ḥadīth and Islamic law in the eyes of his contemporaries. However, his scholarly contributions went beyond these fields, encompassing treatises on hayʾa, magic squares, logic, and local history. Although the latter two works, along with several other writings attributed to him by Islamicate bibliographers, have not survived to the present era, he has garnered prominence for his notable trio of hayʾa works, particularly his Muntahá which exerted a significant influence on the evolution of hayʾa literature. Defining the term hayʾa, which literally means “shape” but is usually translated as “configuration” in the context of astronomy, is challenging because it is ascribed to a cluster of astronomical works whose characteristics are not always entirely identical. However, with caution, it might be suggested that these works sought to present a non-technical overview of Ptolemy’s Almagest. Since the second half of the 10th century and in the decades following, the majority of hayʾa writers began modifying Ptolemaic planetary models by considering the physical existence of the celestial spheres. al-Kharaqī’s Muntahá is one of the earliest works to follow this novel trend.
The volume is composed of 15 papers totally or partially relevant to the astrolabe. Eight of the papers were formerly presented in a conference in April, 2014 held at the Warburg Institute, University of London. The entire set, except the last one, appeared in 2017 as a special issue of the journal Medieval Encounters 23.1-5. Now a slightly revised and updated version of the papers, plus to an epilogue, appear in this book.
More than any other ancient or medieval scientific instrument, the astrolabe, over the past 150 years, has drawn the attention of modern scholars who have attempted to shed light on the mathematical, astronomical, practical and pedagogical aspects of the instrument that appropriately reflects the sophisticated level of medieval science and craftsmanship. Nevertheless, there are still numerous texts and surviving specimens of artefact that deserve further attention. This volume, therefore, aims to fill a certain number of gaps by addressing several unpublished and unstudied texts and examining some physical astrolabes.
The journal, as its editor-in-chief announced in the sixth issue, aims “to acquaint those who are interested in the scientific heritage of Iran and other parts of the Islamic world with scientific researches in this field, to inform them of events in the history of science taking place in Iran, and to provide a context for circulation of scientific contributions in the history of exact and natural sciences from the Islamic period.” The language policy of the journal has changed over the course of its publication. In the first two issues, Persian was the only language used. However, from then on, the policy changed to include English and French. From the beginning, all abstracts of articles have been printed both in English and Persian.
Translations by Hamid Bohloul
In this paper, we trace colophons in Arabic and Persian treatises on the mathematical and related sciences from the tenth to the nineteenth century across Islamicate societies in Asia and Africa. We ask whether there are specific features that characterize them in those disciplines in dependence on the time, the locality or the languages in which they were either produced or copied and whether there are recognizable trends that demarcate periods of change and set geographical, political or cultural boundaries. Our answers will be preliminary and limited, because such questions presuppose the systematic collection of a huge range of data and their digital investigation. Although we have collected colophons over the years and have digital access to various manuscript collections, our material was not assembled with the direct aim of writing a history of colophons in the mathematical and related sciences. We assembled colophons, because we collected texts on specific subject matters such as Euclid’s Elements or specific times and regions such as the Timurid, Ottoman and Safavid Empires in the fifteenth, sixteenth and seventeenth centuries. Despite the methodological shortcomings, our random set of colophons allows a number of observations, which will be helpful for a more systematic approach to the questions of which kind of information was stored in colophons and thus was considered desirable, useful or even necessary in different contexts. We report our results in eight sections. Section 1 highlights the advantages that a systematic, large-scale investigation of colophons can yield. Section 2 surveys information about the time of emergence of colophons in treatises on the mathematical and related sciences. Section 3 lists the religious elements of colophons. Section 4 presents the main types of colophons found in texts from the mathematical and related sciences. Section 5 discusses socio-cultural components. Section 6 focuses on statements on the history of the treatise provided in colophons. Section 7 describes the formal configurations and placements of colophons. Section 8 presents a few exceptional colophons. At the end, we offer some preliminary conclusions about what colophons can contribute to the history of mathematical and related science in Islamicate societies. The term mathematical and related sciences is used in this paper to encompass the range of disciplinary fields that historical actors counted among the mathematical sciences, including different forms of geography and mapmaking.
Astronomy provided tables of latitudes and longitudes of the moon, lunar mean motions, or lunar mansions; offered new models of the lunar orbit; and explained and visualized lunar phases and eclipses in often colourful diagrams. Lunar astrology depended on the knowledge of the moon and its path through specific groups of stars called lunar mansions or stations. On this basis, astrologers determined the birth horoscope and character, physiognomy, and future of a girl or a boy. They could also specify with this kind of information the natural or political future of an empire or a city or predict rain, winds, floods, and periods of heat, cold, or dryness. Eclipses were threatening social events that needed special prayers and decisive measures of the rulers to calm the population. Scholars also studied eclipses in the field of optics to better understand vision, light, and colour.
Natural philosophy discussed the coming into being of the universe and its components. The sphere of the moon separates the celestial from the terrestrial realm and the elements. Earthquakes, rainbows, tides, conception, gestation of the fetus, and birth were all discussed with respect to the moon and its movements.
In the religious realm, the first visibility of the crescent after the conjunction of the sun and the moon was and is of great importance for Muslims, in particular at the beginning of Ramadan. Astrologers and timekeepers tried to calculate the rise of the moon over the horizon and debated the factors that conditioned or impeded its visibility. For their part, religious scholars often considered such methods insufficient and insisted on human sighting of the moon to determine particular holidays and rituals.
During the reign of Sultan Bayezid II (from 1481 to 1512), most probably in Istanbul, an anonymous astronomer composed an untitled Persian treatise about Kāshānī’s equatorium, and dedicated it to the Sultan. Having found the only manuscript of this Persian treatise, the late Edward S. Kennedy surmised that the original work of Kāshānī was lost. He started his investigation of the equatorium using the Persian text and published two papers, one on the Plate of Conjunctions in 1947, and the other on the equatorium in 1950. In 1951 he discovered that a manuscript of Kāshānī’s Nuzha was preserved in the India Office Library in London, but he carried on his research without paying much attention to this original work of Kāshānī. The result was two more papers in the same year, 1951. It was only in his last paper in 1952 that he included some information about the original Arabic text. Eventually, in 1960 he published a book on the instrument entitled The Planetary Equatorium of Jamshīd Ghīyāth al-Dīn al-Kāshī, which included a facsimile of the Persian text, an English translation and a commentary. Kennedy also discussed briefly some of the appendices Kāshānī published in the supplementary tract.
As nearly all of Kennedy’s contribution is based on the Persian treatise of the anonymous Ottoman astronomer, it is worth studying Kāshānī’s own text to learn more about his equatorium and his scientific career. In the present chapter I describe some of the features of the original text and explain how the three additional plates described in the Nuzha can be used to find the true longitudes of the superior planets (Mars, Jupiter and Saturn) and of Venus. I also show how the equatorium can be used for different geographical longitudes.
تابعی ریاضی، تقریباً معادل تابع سینوس در مثلثات امروزی و مهمترین تابع مثلثاتی نجوم در دورۀ اسلامي. جَيب که امروزه آن را با
Sin
نمایش میدهند در وهلۀ اول برای کمان تعریف میشود و در ریاضیات دوره اسلامی دو تعریف معادل داشته است: الف- نيمي از وترِ دو برابرِ هر كمان ؛ ب- عمودي كه از يك طرف كمان، به قطر گذرنده از طرف ديگر كمان وارد ميشود. زیج حبش حاسب کهنترین متنی است که این تعریف در آن آمده است. برخي از رياضيدانان، مانند ابوريحان بيروني و نصیرالدین طوسی، هر دو تعريف را يكسان دانسته و از آنها در آثار خود استفاده كردهاند. اما برخي تعريف اول را خالی از اشكال ندانستهاند، زيرا طبق این تعریف کمانهای بزرگتر از 180 درجه و کوچکتر از 360 درجه دارای جیب نخواهند بود؛ چون داراي كمان دو برابر خود نيستند. برخي نيز براي رفع اين ايراد، راهي براي محاسبۀ دو برابر كمان پيشنهاد كردهاند؛ بدين ترتيب كه هر گاه دو برابر كماني از كل دايره بزرگتر باشد، كل دايره را از آن كم ميكنيم؛ باقيمانده، معادل دو برابر كمان مورد نظر است. در ریاضیات دوران اسلامی، جَیب مستوی، جَیب راست و جَیب مبسوط معادل جَیب به کار میرفتهاند.
As expected, Ptolemy’s successors attempted to achieve more accurate results. Muʾyyad al-Dīn al-ʿUrḍī (ca. 1200-ca. 1266) criticized Ptolemy’s order of planets and the accuracy of his computations by carefully examining Ptolemy’s texts rather than relying solely on observations. His objections led to a change in the position of Venus; it was previously believed to be immediately beneath the sun, but al-ʿUrḍī stated that it should be considered a superior planet, exactly over the sun. Quṭb al-Dīn al-Shīrāzī (1236-1311), one of al-ʿUrḍī’s colleagues at the Maragha observatory, accepted these criticisms and their results without question.
Later, Ghīyāth al-Dīn Jamshīd al-Kāshī (or Kāshānī) (d. 1429) revisited the problem by writing a monograph titled Sullam al-samāʾ (Ladder towards the Heaven), which exclusively focused on planetary distances and sizes. In his work, he approved most of al-ʿUrḍī’s remarks, although he strongly opposed the new order of planets. The core of al-Kāshī’s argument was based on a more precise computation of lunar and solar distances. He repeated nearly all of Ptolemy’s steps with greater precision and eventually concluded that the established view is absolutely authentic, and thus, no alteration in the order of planets would be necessary.
My MA thesis, which is partially uploaded here, primarily focuses on al-ʿUrḍī’s criticisms and al-Kāshī’s mathematical method to assess al-ʿUrḍī’s claim. To achieve this, I have edited the Arabic text of al-Kāshī’s Sullam al-samāʾ based on ten copies and one lithograph edition and translated it into Persian. In the commentary section, I have carefully studied al-ʿUrḍī’s assertion through the hay’a works of Shīrāzī, which was likely the source of al-Kāshī, and then discussed the method used by al-Kāshī to refute the idea that Venus is a superior planet.
Ghīyāth al-Dīn Jamshīd Kāshānī (ca. late 14th century - 22 June 1429), the renowned Iranian mathematician and astronomer, was one of the five astronomers in the Islamicate world who designed an equatorium. In 1416 CE (818 AH), he compiled an Arabic treatise on the construction and use of his equatorium. He named the treatise Nuzhat al-ḥadā’iq (Excursion to the gardens) and the instrument Ṭabaq al-manāṭiq (Plate of deferents), respectively. After nearly a decade, in 1426, he wrote another Arabic tract comprised of ten appendices aimed at improving the instrument. Both of these works have hitherto remained unpublished.
Unfortunately, no physical specimen of Kāshānī’s equatorium has been passed down to us. Therefore, it is yet to be demonstrated whether the instrument can be constructed with the same applications claimed by its inventor or not. Moreover, neither of the extant manuscripts of this work, which I consulted, bears even a sketch of the instrument. Furthermore, Kāshānī does not provide any reasons for the authenticity of his graphical solutions, nor does he point to the underlying theories of the instrument.
In this thesis, I address the abovementioned issues. Hence, I attempted to reconstruct different forms of equatoria on the basis of the descriptions he provided, displaying the functionality of the graphical solutions through numerous new figures, and demonstrating the veracity of the provided instructions for determining planetary longitudes with the instrument, to the extent possible. These studies constitute a substantial part of the commentary that follows my critical editions and Persian translations of the two Arabic treatises. These materials are preceded by my introduction, which concerns Kāshānī’s intellectual career prior to his relocation to Samarqand.
The First Comprehensive Hayʾa Work on Ptolemaic Cosmology. Hanif Ghalandari (Miras-e Maktoob,
Tehran, 2020). Pp. 184 + 696 + 20. $37. ISBN 9786002031907 (paper).
Abū Muḥammad ʿAbd al-Jabbār al-Kharaqī (1084–1158) was revered as a scholar of ḥadīth and Islamic law in the eyes of his contemporaries. However, his scholarly contributions went beyond these fields, encompassing treatises on hayʾa, magic squares, logic, and local history. Although the latter two works, along with several other writings attributed to him by Islamicate bibliographers, have not survived to the present era, he has garnered prominence for his notable trio of hayʾa works, particularly his Muntahá which exerted a significant influence on the evolution of hayʾa literature. Defining the term hayʾa, which literally means “shape” but is usually translated as “configuration” in the context of astronomy, is challenging because it is ascribed to a cluster of astronomical works whose characteristics are not always entirely identical. However, with caution, it might be suggested that these works sought to present a non-technical overview of Ptolemy’s Almagest. Since the second half of the 10th century and in the decades following, the majority of hayʾa writers began modifying Ptolemaic planetary models by considering the physical existence of the celestial spheres. al-Kharaqī’s Muntahá is one of the earliest works to follow this novel trend.
The volume is composed of 15 papers totally or partially relevant to the astrolabe. Eight of the papers were formerly presented in a conference in April, 2014 held at the Warburg Institute, University of London. The entire set, except the last one, appeared in 2017 as a special issue of the journal Medieval Encounters 23.1-5. Now a slightly revised and updated version of the papers, plus to an epilogue, appear in this book.
More than any other ancient or medieval scientific instrument, the astrolabe, over the past 150 years, has drawn the attention of modern scholars who have attempted to shed light on the mathematical, astronomical, practical and pedagogical aspects of the instrument that appropriately reflects the sophisticated level of medieval science and craftsmanship. Nevertheless, there are still numerous texts and surviving specimens of artefact that deserve further attention. This volume, therefore, aims to fill a certain number of gaps by addressing several unpublished and unstudied texts and examining some physical astrolabes.
The journal, as its editor-in-chief announced in the sixth issue, aims “to acquaint those who are interested in the scientific heritage of Iran and other parts of the Islamic world with scientific researches in this field, to inform them of events in the history of science taking place in Iran, and to provide a context for circulation of scientific contributions in the history of exact and natural sciences from the Islamic period.” The language policy of the journal has changed over the course of its publication. In the first two issues, Persian was the only language used. However, from then on, the policy changed to include English and French. From the beginning, all abstracts of articles have been printed both in English and Persian.