In De magnete, Gilbert frequently appealed to diagrams. As result of a focus on the experimental methodology of the treatise, its diagrammatic dimension has been overlooked in the scholarship. This paper argues that, in De magnete, at least some diagrams are epistemically relevant; specifically, Gilbert moves from experiments to concepts and theories through diagrams. To show this, I analyze the role that the “Diagram of motions in magnetick orbes” plays in the formulation of Gilbert's rule of alignment of magnetic bodies (...) within the orb of virtue. If it turns out that diagrams play a genuine role in Gilbert's magnetic investigations, then his investigative strategy goes beyond mere experimentalism. (shrink)

Historians have used university statutes and acts to reconstruct the official astrology curriculum for students in both the arts and medical faculties, including the books studied, their order, and their relation to other texts. Statutes and acts, however, cannot offer insight into what actually happened during lectures and in the classroom: in other words, how and why astrology was taught and learned in the medieval university. This paper assumes that the astrology curriculum is better understood as the set of practices (...) that constituted it and gave it meaning for both masters and students. It begins to reconstruct what occurred in the classroom by drawing on published and unpublished lecture notes. These offer insight into how masters presented the material as they did, and why. The paper argues three points: first, the teaching of astrology centered on demonstrations involving astrological instruments: specifically, various kinds of paper astrolabes. Second, the astrological instruction focused on conveying the pragmatics of astrology rather than esoteric, theoretical issues. Finally, astrology as it was taught in the arts curriculum was explicitly intended to provide a foundation for students who would advance to study medicine at the university. (shrink)

Questions about how closure is achieved in disputes involving new observational or experimental claims have highlighted the role of bodily knowledge possibly irreducible to written experimental protocols and instructions how to build and operate instruments. This essay asks similar questions about a scenario that is both related and significantly different: the replication of an invention, not of an observation or the instrument through which it produced. Furthermore, the machine considered here—Galileo’s compass or sector—was not a typical industrial invention (like a (...) spinning jenny), but a mathematical invention (a calculator), that is, a machine that produces numbers, not yarn. This case study describes some of the similarities and differences between replicating experiments, traditional machines producing material outputs, and mathematical inventions yielding calculations or information. This comparison indicates that, as in other kinds of replication, the replication of mathematical inventions involves texts (the calculator’s instructions) but that in this case bodily knowledge cannot be properly described as either tacit or explicit. It rather takes the shape of memory—muscle memory—that may be recalled from reading the instructions. (shrink)

This survey outlines a history of museums written through biographies of objects in their collections. First, the mechanics of the movement of things and the accompanying shifts in status are considered, from manufacture or growth through collecting and exchange to the museum. Objects gathered meanings through associations with people they encountered on their way to the collection, thus linking the history of museums to broader scientific and civic cultures. Next, the essay addresses the use of items once they joined a (...) collection, whether classificatory, analytical, or in display. By thus embedding the study of scientific practice in material culture, this approach contributes to constructivist histories of science. The final section addresses the role of objects in the experience of the visitors, emphasizing how fruitful the history of museum objects can be in the study of the public engagement with science. (shrink)

This paper argues that Kepler considered his work in optics as part of natural philosophy and that, consequently, he aimed at change within natural philosophy. Back-to-back with John Schuster’s claim that Descartes’ optics should be considered as a natural philosophical appropriation of innovative results in the tradition of practical and mixed mathematics the central claim of my paper is that Kepler’s theory of optical imagery, developed in his Paralipomena ad Vitellionem (1604), was the result of a move similar to Descartes’ (...) by Kepler. My argument consists of three parts. First, Kepler borrowed a geometrical model and experiment of optical imagery from the mélange of mixed and practical mathematics provided in the works of the sixteenth-century mathematicians Ettore Ausonio and Giovanni Battista Della Porta. Second, Kepler criticized the Aristotelian theory of light and he developed his own alternative metaphysics. Third, Kepler used his natural philosophical assumptions about the nature of light to re-interpret the model of image formation taken from Della Porta’s work. Taken together, I portray Kepler’s theory of optical imagery as a natural philosophical appropriation of an innovative model of image formation developed in a sixteenth-century practical and mixed mathematical tradition which was not interested in questioning philosophical assumptions on the nature of light. (shrink)

This paper examines the role of mathematical instrument makers in establishing a public culture of precision measurement in early-modern England. I argue that this culture was promoted through trials and demonstrations, in the context of which artisans held a privileged position. The trials described here cover land surveying, the measurement of magnetic variation, and standards of measurement for customs and excise. These trials were decisive moments in the ‘cultural biographies’ of precision instruments. I ask how it was that instrument makers (...) were able to assume positions of authority, and what this means for our understanding of the socio-material system of precision measurement in the early-modern period, and the contemporary rise of ‘experimental’ and ‘philosophical’ trials. Because practical mathematics was a self-consciously economic activity – motivated by trade, commerce, exploration and colonization – direct connections to natural philosophy are significant, a point explored in my conclusion. (shrink)

This paper investigates the emergence, in the second part of the 17th century, of a new body of experimental knowledge dealing with the chemical transformations of water taking place in plants. We call this body of experimental knowledge a “chemical history of vegetation.” We show that this chemical natural history originated, in terms of recipes and methods of investigation, in the works of Francis Bacon and that it was constructed in accordance with Bacon's precepts for putting together natural and experimental (...) histories. Our paper covers a wide array of experimental investigations, carried out by people with different backgrounds, theoretical assumptions, and metaphysical allegiances (Thomas Browne, Robert Sharrock, Robert Boyle, Nehemiah Grew, John Beale, and John Evelyn). We claim that, despite their differences, these naturalists had a lot in common. First, they treated plants as laboratories of chemical investigation. Second, they used the experiments with plants to develop tools, hypotheses, and operational concepts, which travelled from one naturalist to the other, even when their respective explanatory vocabularies were widely different. Third, we show that some of them also manifested an interest in defining and clarifying the limits and structure of this new body of experimental knowledge, displaying, thus, a certain disciplinary unity. (shrink)

The astronomer Ole Rømer emphasized the mechanical nature of the practice of astronomy and this paper attempts to unravel what Rømer meant by the close association between mechanics and astronomy. The point of departure is Rømer's work with Tycho Brahe's observations and his stay at the Royal Academy of the Sciences in Paris. Analyses of Rømer's letters and treatises show that he not only focused on direct presentations of observations and instruments, but demanded an independence of his results that went (...) beyond the rhetoric of first-hand knowledge. Rømer wanted his observations and instruments to demonstrate the physical theories themselves, rather than asking for theories to be accepted on his authority. His invention of the meridian circle with its facility for cross-checking measurements is seen in connection with this drive to make what is observed ‘deserve credit in its own right rather than because of the observer.’. (shrink)

This paper explores the use of new scientific techniques to examine collections of historic scientific apparatus and other technological artefacts. One project under discussion uses interferometry to examine the history of lens development, while another uses X-ray fluorescence to discover the kinds of materials used to make early mathematical and astronomical instruments. These methods lead to surprising findings: instruments turn out to be fake, and lens makers turn out to have been adept at solving the riddle of aperture. Although exciting, (...) in some ways this is neither novel nor particularly unusual. After all, lab techniques have been used in art and archaeological collections for a very long time. In fact, scientific instruments themselves have been examined in this way since at least the 1950s. What, then, is special about the use of new instruments to examine old instruments? We argue that the answer has less to do with measuring historical innovation or establishing priority, and more to do with networks of craft know-how that, typically, have left no other historical traces than those embodied in surviving instruments themselves. We show, in particular, how collections of objects can be mobilised within wider histories of knowledge, placing instruments within a dynamic interplay of craft knowledge, expertise, labour, commerce, and material exchange, over the longue durée. Finally, we suggest that these kinds of lab analyses can be given an extra dimension through the use of computational modelling, and we introduce the “Tools of Knowledge” project, which is designed to bring together XRF with techniques from the digital humanities, in order to tell a new story about the development of scientific instruments from the 16th to the 20th century. (shrink)

While Newton tried to make his telescope into a proof of the supremacy of his theory of colours over older theories, his instrument was welcomed as a way to shorten telescopes, not as a way to solve the problem of chromatic aberration. This paper argues that the image published together with the report on Newton’s telescope in Philosophical Transactions (1672) encouraged this reception. The differences between this visualization and other images of Newton’s telescope, especially that published in Opticks (1704), are (...) discussed. This paper shows that the image in Opticks adopted characteristics of a Cartesian program of visualization of machines and instruments which complemented a rhetoric which attributed primacy to theory over practice. The differences between the images in Philosophical Transactions and Opticks are also considered within the broader institutional context of Newton’s attitude towards the Royal Society. (shrink)