Muḥyī al-Dīn al-Maghribī’s lunar measurements at the Maragha observatory

This paper is a technical study of the systematic observations and computations made by Mu?yī al-Dīn al-Maghribī (d. 1283) at the Maragha observatory (north-western Iran, c. 1259–1320) in order to newly determine the parameters of the Ptolemaic lunar model, as explained in his Talkhī? al-majis?ī, “Compendium of the Almagest.” He used three lunar eclipses on March 7, 1262, April 7, 1270, and January 24, 1274, in order to measure the lunar epicycle radius and mean motions; an observation on April 20, 1264, to determine the lunar eccentricity; an observation on August 29, 1264, to test the model; and another on March 15, 1262, for measuring the lunar parallax. In the second period of activity at the Maragha observatory, Shams al-Dīn Mu?ammad al-Wābkanawī (c. 1254–1320) adopted all of al-Maghribī’s parameter values in his Zīj, but decreased his value for the mean longitude of the moon at epoch by 0;13,11 $^{\circ }$ . By comparing the times of the new moons and lunar eclipses in the period of 1270–1320 as computed from the astronomical tables of the Maragha tradition with the true modern ones, it is argued that this correction was very probably the result of actual observations.     

Solar and lunar observations at Istanbul in the 1570s

From the early ninth century until about eight centuries later, the Middle East witnessed a series of both simple and systematic astronomical observations for the purpose of testing contemporary astronomical tables and deriving the fundamental solar, lunar, and planetary parameters. Of them, the extensive observations of lunar eclipses available before 1000 AD for testing the ephemeredes computed from the astronomical tables are in a relatively sharp contrast to the twelve lunar observations that are pertained to the four extant accounts of the measurements of the basic parameters of Ptolemaic lunar model. The last of them are Taqī al-Dīn Mu?ammad b. Ma‘rūf’s (1526–1585) trio of lunar eclipses observed from Istanbul, Cairo, and Thessalonica in 1576–1577 and documented in chapter 2 of book 5 of his famous work, Sidrat muntaha al-afkar fī malakūt al-falak al-dawwār (The Lotus Tree in the Seventh Heaven of Reflection). In this article, we provide a detailed analysis of the accuracy of his solar (1577–1579) and lunar observations.     

‘Land-marks of the universe’: John Herschel against the background of positional astronomy

John Herschel (1792–1871) was the leading British natural philosopher of the nineteenth century, widely known and regarded for his work in philosophy, optics and chemistry as well as his important research and popular publications on astronomy. To date, however, there exists no extended treatment of his astronomical career. This paper, part of a larger study exploring Herschel's contributions to astronomy, examines his work in the context of positional astronomy, the dominant form of astronomical practice throughout his lifetime. Herschel, who did not himself practice positional astronomy and who was known for his non-meridional observations of specific stellar objects, was nonetheless a strong advocate for positional astronomy—but for very different reasons than the terrestrial applications to which it was most often put. For Herschel, the star catalogues of positional astronomy were the necessary observational foundation upon which information about the stars as physical objects could be constructed. Positional astronomy practiced in the great national observatories was not about navigation or timekeeping; it was a way to standardize stellar observations and make them useful data for constructing theories of the stars themselves. For Herschel, the seeds of the new astronomy emerged from the practices of the old.     

Before words: reading western astronomical texts in early nineteenth-century Japan

SUMMARY

In 1803, the most prominent Japanese astronomer of his time, Takahashi Yoshitoki, received a newly imported Dutch translation of J. J. Lalande's ‘Astronomie’. He could not read Dutch, yet he dedicated almost a year to a close examination of this massive work, taking notes and contemplating his own astronomical practices. How did he read a book he could not read? Following the clues Yoshitoki left in his notes, we discover that he found meanings not only in words, but also in what are often taken for granted or considered to be auxiliary tools for data manipulation, such as symbols, units, tables, and diagrams. His rendering of these non-verbal textual elements into a familiar format was crucial for Yoshitoki's reading, and constituted the initial step in the process of integrating Lalande's astronomy into Japanese astronomical practices, and the subsequent translation of the text into Japanese.     

The Scientific Interests of Archibald Campbell, 1st Earl of Ilay and 3rd Duke of Argyll (1682-1761)

Amateur scientists were important in the science of the eighteenth century as patrons, investors in talent and new equipment, as the maintainers of gardens and libraries, and, occasionally, as men who could and did make discoveries or significant innovations. The article shows that the 3rd Duke of Argyll was one of these men. He was also much more. Ilay's interests in science, because of his important political position in Scotland, touched not only his immediate friends but helped to reshape Scottish culture itself. This essay looks at his scientific interests, his political career, and his patronage to argue that the results of his long career in politics were to institutionalize a new set of modern values in most Scottish institutions.     

Different shades of Newton: Herman Boerhaave on Newton mathematicus,philosophus, and optico-chemicus

In this paper I will probe into Herman Boerhaave's (1668–1738) appropriation of Isaac Newton's natural philosophy. It will be shown that Newton's work served multiple purposes in Boerhaave's oeuvre, for he appropriated Newton's work differently in different contexts and in different episodes in his career. Three important episodes in, and contexts of, Boerhaave's appropriation of Newton's natural philosophical ideas and methods will be considered: 1710–11, the time of his often neglected lectures on the place of physics in medicine; 1715, when he delivered his most famous rectorial address; and, finally, 1731/2, in publishing his Elementa chemiae. Along the way, I will spell out the implications of Boerhaave's case for our understanding of the reception, or use, of Newton's ideas more generally.     

Henry More and the development of absolute time

This paper explores the nature, development and influence of the first English account of absolute time, put forward in the mid-seventeenth century by the ‘Cambridge Platonist’ Henry More. Against claims in the literature that More does not have an account of time, this paper sets out More's evolving account and shows that it reveals the lasting influence of Plotinus. Further, this paper argues that More developed his views on time in response to his adoption of Descartes' vortex cosmology and cosmogony, providing new evidence of More's wider project to absorb Cartesian natural philosophy into his Platonic metaphysics. Finally, this paper argues that More should be added to the list of sources that later English thinkers – including Newton and Samuel Clarke – drew on in constructing their absolute accounts of time.     

The union of arts and sciences in the eighteenth century: Lorenz Spengler (1720–1807), artistic turner and natural scientist

The life and career of Lorenz Spengler (1720–1807) provides evidence to support the view that the eighteenth century was a period when there was a fruitful interrelationship between the arts, crafts, and sciences in the courts and capitals of Europe. Spengler was trained as a turner, and was appointed teacher of ornamental turning to the Danish royal family and turner of the court in 1745. Even in the early years of his artistic career Spengler was interested in electricity and its role in healing, and he became an avid collector of shells and naturalia. Over the years, Spengler's interests turned more to the natural sciences, and in 1771 he was appointed director of the King's Kunstkammer. Only by considering both aspects of Spengler's career can his scientific activities be placed in their proper historical context.     

Essay review

This paper treats van Helmont's attack on Aristotle as an example of the difficulty of accounting for one author's attack on another by simply comparing the texts of the two authors. The Aristotle that van Helmont is attacking is the Aristotle represented in contemporary textbooks, and the attack on his authority is closely connected to the attack on the importance of verbal disputation in education. The importance of knowledge of Aristotle and of argumentative skills means van Helmont displays them to claim competence in them, while arguing they are worthless, and states many of his own doctrines as denials of Aristotelian doctrines. After a brief account of van Helmont's cosmology, three texts of his are examined: the conclusion of Causae et initia naturalium, where van Helmont demonstrates the worthlessness of Aristotelian method, by giving an example of his own method's greater success, the beginning of Physica Aristotelis et Galeni ignara, where he argues in Aristotelian terms against an Aristotelian definition of nature, and his general attack on Aristotelian method and on verbal disputation in Logica inutilis.     

The Lunar Theories of Tycho Brahe and Christian Longomontanus in the Progymnasmata and Astronomia Danica

Tycho Brahe's lunar theory, mostly the work of his assistant Christian Longomontanus, published in the Progymnasmata (1602), was the most advanced and accurate lunar theory yet developed. Its principal innovations are: the introduction of equant motion for the first inequality in order to separate the determination of direction and distance; a more accurate limit for the second inequality although requiring a more complex calculation; additional inequalities of the variation and, in place of the annual inequality in Tycho's earlier theory, a reduction in the equation of time; in the latitude theory a variation of the inclination of the orbital plane and an inequality of the motion of the nodes; a reduction in the range of variation of distance, parallax, and apparent diameter. Some of these were already present in Tycho's earlier lunar theory (1599), but all were changed in notable ways. Twenty years later Longomontanus published a modified version of the lunar theory in Astronomia Danica (1622), for the purpose of facilitating the calculation through new correction tables, and also explained his reasons for parts of the theory in the Progymnasmata. This paper is a technical study of both lunar theories.     

Viète's Controversy with Clavius Over the Truly Gregorian Calendar

Some twenty years after the Gregorian calendar reform, towards the end of his life, François Viète published his own calendar proposal. This treatise contains a sharp attack against the Jesuit scholar Clavius, the mathematical mind behind the reform. Understandably enough, Clavius prepared a negative reply. Viète heard of it and exploded in a fit of rage, ``I demonstrated that you are a false mathematician [ . . . ], and a false theologian.'' Sadly, Clavius' rejection, added as a chapter to his monumental apology of the Gregorian reform, appeared when Viète had already passed away.Viète seriously believed that the true aim of the Gregorian reform has been betrayed and he was furious about some logical inconsistencies which he claimed to have found in Clavius' calendar. Clavius apparently confused solar day and epactal day (or ``tithi''), the thirtieth part of a lunar month. This is the very core of Viète's attack against Clavius whom he accused of having introduced a false lunar period (``falsa periodus lunaris''). But his own work has some logical inconsistencies too. For instance, he reproaches Clavius for having introduced lunar months of 31 days which, indeed, are unrealistic. Grievously, his own rules can likewise give rise to lunations of unnatural lengths.In order to understand these subtle twists reader and author must work largely through both Clavius and Viète's methods of Easter reckoning. The fruit of all those efforts might be an insight into Viète's clear mathematical thinking. His calendar, however, was never considered.     

The Accuracy and Use of Sextants and Watches in Rupert's Land in the 1790s

The purpose of this paper is to draw attention to the sextants and watches employed at the end of the eighteenth century in surveying Rupert's Land, the vast territory of the Hudson's Bay Company (HBC), and to discuss their usage and accuracy. The results provide information on the standards of manufacture at the time, on the reliability of the contemporary latitude and longitude of various fur-trading posts, and on the careers of the surveyors themselves. The sextant readings are shown to have a standard deviation of about 20 arcseconds when used in a vertical position to find altitudes of the Sun and stars, and about 40 arcseconds otherwise, for finding lunar distances. Because of the use of artificial horizons, these conclusions imply that, at a 95% (2σ) confidence level, a single determination of latitude is reliable to ±20 arcseconds (600 m on the Earth's surface), of longitude ±20 arcminutes (approximately 60 km in Rupert's Land), and a single determination of local apparent time is reliable to ±3 s. The watches, it appears, could run at a steady rate with errors of less than a minute for a period of a week or two.     

The Prussian Mining Official Alexander von Humboldt

From summer 1792 until spring 1797, Alexander von Humboldt was a mining official in the Franconian parts of Prussia. He visited mines, inspected smelting works, calculated budgets, wrote official reports, founded a mining school, performed technological experiments, and invented a miners’ lamp and respirator. At the same time he also participated in the Republic of Letters, corresponded with savants in all Europe, and was a member of the Leopoldine Carolinian Academy and the Berlin Gesellschaft Naturforschender Freunde. He collected minerals, made geognostic observations, performed chemical and physiological experiments, read the newest scientific journals, and prepared and published texts on mineralogy, geognosy, chemistry, botany and physiology. Humboldt did his scientific investigations alongside his administrative and technical work. This raises the question of whether there were fruitful interactions between Humboldt's technical-administrative work and (parts of) his natural inquiry. I argue that the mining official Humboldt was a late eighteenth-century figure of hybrid savant-technician. Mines and smelting works provided numerous opportunities for studies of nature. Humboldt systematically used inspection tours for mineralogical and geognostic observations. He transformed mines into chemical laboratories, and he transferred knowledge and material items from his natural inquiries in mines to academic institutions. The main objective of this paper is to illuminate the persona of savant-technician (or scientific-technological expert) along with Humboldt's mixed technological and scientific work during his term as mining official.     

Knut Lundmark,Meteors and an Early Swedish Crowdsourcing Experiment

Mid twentieth century meteor astronomy demanded the long-term compilation of observations made by numerous individuals over an extensive geographical area. Such a massive undertaking obviously required the participation of more than just professional astronomers, who often sought to expand their ranks through the use of amateurs that had a basic grasp of astronomy as well as the night sky, and were thus capable of generating first-rate astronomical reports.

When, in the 1920s, renowned Swedish astronomer Knut Lundmark turned his attention to meteor astronomy, he was unable to rely even upon this solution. In contrast to many other countries at the time, Sweden lacked an organized amateur astronomy and thus contained only a handful of competent amateurs. Given this situation, Lundmark had to develop ways of engaging the general public in assisting his efforts. To his advantage, he was already a well-established public figure who had published numerous popular science articles and held talks from time to time on the radio. During the 1930s, this prominence greatly facilitated his launching of a crowdsourcing initiative for the gathering of meteor observations.

This paper consists of a detailed discussion concerning the means by which Lundmark's initiative disseminated astronomical knowledge to the general public and encouraged a response that might directly contribute to the advancement of science. More precisely, the article explores the manner in which he approached the Swedish public, the degree to which that public responded and the extent to which his efforts were successful. The primary aim of this exercise is to show that the apparently recent Internet phenomenon of ‘crowdsourcing’, especially as it relates to scientific research, actually has a pre-Internet history that is worth studying. Apart from the fact that this history is interesting in its own right, knowing it can provide us with a fresh vantage point from which to better comprehend and appreciate the success of present-day crowdsourcing projects.     

Science and the romantic movement

Several authors have used the expression ‘formal asymmetry’ to characterize Einstein's method of introducing conceptual innovations. Prior to his use of formal asymmetries, however, Einstein relied upon analogy to introduce his major concepts, but without satisfactory results. He gradually refined another technique, reflection upon empirical problems, into the method of formal asymmetries, with impressive results. This historical study, based upon a textual analysis of Einstein's publications, raises a series of questions regarding the place of formal asymmetries in his work.     

The platypus in Edinburgh: Robert Jameson,Robert Knox and the place of the Ornithorhynchus in nature, 1821–24

The duck-billed platypus, or Ornithorhynchus, was the subject of an intense debate among natural historians in the late eighteenth and early nineteenth centuries. Its paradoxical mixture of mammalian, avian and reptilian characteristics made it something of a taxonomic conundrum. In the early 1820s Robert Jameson (1774–1854), the professor of natural history at the University of Edinburgh and the curator of the University's natural history museum, was able to acquire three valuable specimens of this species. He passed one of these on to the anatomist Robert Knox (1791–1862), who dissected the animal and presented his results in a series of papers to the Wernerian Natural History Society, which later published them in its Memoirs. This paper takes Jameson's platypus as a case study on how natural history specimens were used to create and contest knowledge of the natural world in the early nineteenth century, at a time when interpretations of the relationships between animal taxa were in a state of flux. It shows how Jameson used his possession of this interesting specimen to provide a valuable opportunity for his protégé Knox while also helping to consolidate his own position as a key figure in early nineteenth-century natural history.     

Scientific Governance in Britain 1914–79

John Harrison (1693–1776) is regarded as the father of chronometry. During his lifetime, he relentlessly pursued one of humankind's greatest and oldest challenges—that of finding the longitude at sea. In succeeding (according to the rules dictated by an Act of Parliament), he bequeathed to humankind the most accurate portable timekeeper the world had ever seen. It is a remarkable fact that his timekeeper, known today as H4, remains more accurate than the majority of expensive mechanical wristwatches manufactured today. Such accuracy required novel approaches to address the various difficulties that befall all mechanical watches, and Harrison overcame many of these with his own innovations. The reduction or elimination of friction is one such problem with clocks and watches, and from an early age Harrison demonstrated his mastery in this subject. This is typified by his choice of woods in his early clocks, and in later clocks by his ‘grasshopper’ escapement. In the 1750s, Harrison's attention switched from clocks to watches, necessitating a hardwearing, low friction material to be found for the pallets in the escapement of his timekeepers. He found these properties in diamond, and in utilizing this to great effect in H4's escapement, he became one of the first people to use diamond as a high-tech material. This paper describes a scientific investigation into the diamond pallets of H4 using Raman microscopy, X-ray diffraction and optical microscopy, to elucidate why diamond was used rather than a more conventional jewel such as ruby, and to gain some insight into how Harrison might have achieved their unconventional morphology. From the evidence presented here, together with evidence collected from primary sources, it is shown that his use of diamond as a hard, low friction material was nothing other than extraordinary, and should be regarded in the same high esteem as his other technological gifts to the world.     

Bailey Willis (1857-1949): Geological Theorizing and Chinese Geology

Bailey Willis was the second major American geologist to undertake reconnaissance research in China--in the years 1903-04. Together with the stratigrapher Eliot Blackwelder, topographer Harvey Sargent, and guide Li Shan, he travelled first in Shandong Province, then from Peking to Xian, thence across the mountains into Sichuan, and then by river via the Yangzi Gorges to Shanghai. It was hoped that they would discover the primeval ancestor of trilobites in China, but the search proved unsuccessful. Willis's stratigraphic findings are described, as are his structural interpretations of what he observed in China. His work in China gave rise to some unfounded speculations about the possible causes of lateral Earth movements, due to rocks of different densities being adjacent to one another in the Earth's crust. These ideas were followed by several other 'theories of the Earth' during Willis's later career, some of which were also probably related to his experiences in China. He seemingly practised the formulation of 'multiple working hypotheses'. The paper also discusses the influence of Willis's survey and stratigraphic work on the subsequent development of Chinese geology, with particular attention given to the various meanings of the term 'Sinian System'. Mention is made of later work in China on Lower Cambrian stratigraphy.