Annals of Science最新文献

In the 1720s two Jesuit astronomers working at the court of King João V of Portugal, in Lisbon, received several instruments produced by the best makers in London, Paris and Rome. With the crucial help of the Portuguese diplomatic network contacts with academies, savants and instrument makers were established, seeking technical advice and the best astronomical instruments available at the time. It was in this context that in April 1726 a set of Latin instructions accompanying pendulum clocks made by George Graham were dispatched from London to Lisbon. These unpublished instructions are now preserved in the papers of Giovanni Battista Carbone, one of these Jesuit astronomers, offering a significant window into the procedures and technical details involved in the setting, operation and transport of Graham's astronomical clocks. In this paper, I will not only discuss this important document in the framework of Graham's contributions to astronomy and horology, but also in the perspective of the search for accuracy.

This article discusses the ways in which nineteenth-century geodesists reflected on precision as an epistemic virtue in their measurement practice. Physical geodesy is often understood as a quintessential nineteenth-century precision science, stimulating advances in instrument making and statistics, and generating incredible quantities of data. Throughout most of the nineteenth century, geodesists indeed pursued their most prestigious research problem - the exact determination of the earth's polar flattening - along those lines. Treating measurement errors as random, they assumed that remaining discordances could be overcome by manufacturing better instruments and extending statistical analysis to a larger amount of data. In the second half of the nineteenth century, however, several German geodesists developed sophisticated methodological critiques of their discipline, in which they diagnosed a too-narrow focus on precision among their peers. On their account, geodesists urgently needed to identify and anticipate the causes of the remaining measurement errors that arose from the earth's little understood interior constitution. While mostly overlooked in the literature, these critiques paved the way for many empirical successes in late nineteenth- and early twentieth-century geodesy, including the first convergent measurements of the earth's polar flattening.

This paper explores discussions centred on the activities of the British Board of Longitude to consider the ways in which some men of science, instrument makers and others thought about questions of precision and accuracy, both in principle and in terms of what was possible in practice when making observations at sea. It considers firstly the terminology used in some eighteenth- and early nineteenth-century texts, highlighting the concept of exactness, which was more commonly used to describe one of the desirable qualities of instruments and methods. It then looks at some of the discussions and debates in which the Board of Longitude was involved from the 1760s to think about different actors' expectations of what levels of exactness might be either desirable or possible for day-to-day navigation. The focus is on the ability to make accurate shipboard observations and on the question of what degree of exactness might have been accepted as good enough for routine navigational purposes when at sea.

In 1736/37, Joseph-Nicolas Delisle and Jean Jacques Dortous de Mairan communicated about the clocks that would enable the astronomers of the Saint Petersburg observatory to make highly exact observations. Delisle, who was in charge of the Saint Petersburg observatory, demanded old-fashioned clocks in the manner of Huygens. Mairan, well-versed in astronomy himself, recommended equation clocks. The article uses these seemingly inappropriate preferences to discuss eighteenth-century notions of accuracy and precision in clocks. It analyses the multiple factors that influenced expectations regarding the performance of timekeeping instruments, and draws attention to handling and monitoring practices. The latter reflected the individual user's purposes and experience, but also affected the clocks' going. Furthermore, the article presents the result of a statistical analysis, which serves to evaluate the historical performance of the Saint Petersburg observatory clocks and provides a foil against which Delisle's judgement of them is examined.

We explore the extent to which ancient Greek authors formulated concepts that approximate or encompass our modern notions of precision and accuracy. First, we focus on estimates and measurements of geographic features, astronomical times and positions, and weight. These raise further questions about whether the quantities reported were measured, estimated, or rounded. While ancient sources discuss the use of instruments, it is not always clear that the aim was to achieve what we would today regard as 'precision'. Next, we briefly consider round numbers, observing that they could carry symbolic meaning, while unrounded numbers could give an impression of hard-won achievement. Finally, we examine uses of the word akribeia. This is often translated as 'precision' or 'exactness', and Greek writers sometimes used akribeia to denote an ideal for their inquiries. A brief look at its uses by a number of Greek writers will on the one hand show the mismatch with our term 'precision', and on the other hand throw some light on the aims of Greek investigators.

Marine chronometers, often considered precision instruments, proliferated in navigational practices during the nineteenth century. This paper examines their use in the hands of naval officers in the early-nineteenth century. It argues that both the instruments and their operators required careful management and regulation. In addition, officers learnt and adapted observatory practices relating to the process of data collection and management. Through these means, chronometric data was collected, organized, and reduced to negotiate accurate results.

In the century between the creation of the first large, European astronomical observatory by Tycho Brahe in the 1580s and the national observatories of France and England in the 1660-1670s, astronomers constructed ever more sets of tables, derived from various geometrical and physical models, to compute planetary positions. But how were these tables to be evaluated? What level of precision or accuracy should be expected from mathematical astronomy? In 1644, the Stetin astronomer and calendar-maker Lorenz Eichstadt published a new set of tables, mostly cobbled together from earlier tables, which include a running commentary on how his tables might be expected to match 'observed' planetary positions. His earlier works also often display a rhetoric of 'exactitude' and 'error'. Eichstadt thus offers a case study of explicit discussions of 'precision' in mid-seventeenth astronomy. Although some tables could generate positions to arcseconds, Eichstadt argued that a regime of five arcminutes should be enough for most table users who were, presumably, computing horoscopes.

This article maps out the lexical landscape of precision from the late seventeenth to the early eighteenth century and investigate the various meanings of precision, both as a word and a concept, within the Paris Observatory and beyond. It argues that precision was first an attribute of instruments supposed to produce numerical measurements, like clocks and divided circles or sectors attached to optical devices. Less often, precision was applied to observers, the handling of instruments, and observational methods, including mathematical corrections applied to raw data. When all these aspects were combined the numerical result finally was also deemed to be precise. Moving to the debate about the shape of the Earth that shook the Academy of Sciences in the 1730s, it follows the way in which wider audiences were conveyed the various meanings of precision. Between the Cartesian resistance to the emergence of a professional science of precision and the pedagogical approach followed by the Newtonians such as Maupertuis, it argues that Cassini III embraced the professionalism of modern science, but did not feel that methodological precision was out of the reach of an educated public. While Maupertuis has seemed content with a discussion focusing on the precision of instruments and results, Cassini III set himself the hefty task of producing an accessible account of precision as a method of inquiry.