The aim of this thesis has been to argue, on the basis of primary sources, that Huygens was a pioneer in the field of mechanical engineering. He fits the definition of a mechanical engineer as somebody who develops a novel invention either empirically or theoretically, using known mechanical theories. In the same way, a new invention may come about through transforming an existing machine or instrument thus revolutionizing any future versions of it. Huygens did both he applied a pendulum to existing clocks and transformed the making of precision instruments from that moment onwards. The first chapter of the thesis presents Huygens' works on pendulum clocks and marine clocks. The second chapter is dedicated to Huygens' research and designs of the air pump and linking with the third chapter on matter theory. The fourth chapter focuses on Huygens' designs of various instruments (the telescope, the microscope, the level, the planetarium and others). The final chapter depicts Huygens in the societies in which he lived. Huygens was a pioneer of mechanical engineering because he presented a complete work on mechanics to explain instruments, 'automata', by mathematical axioms and laws. Furthermore, he developed a methodology for improving instruments and machines based on searching for the best materials to obtain the best working models. The Horologium Oscillatorium of 1673, was a textbook, which inspired others to continue a tradition of mechanics for the mechanical engineer. With geometrical ratios he was able to show the applicability of technology in everyday life. Therefore, Huygens took the foundations of mechanics further than his contemporaries did. The geometry he used was the basis, which could simplify and give a quantitative measure of nature and of any man-made instruments alike.

This dissertation is an attempt to understand the role of instruments in the process of knowledge production in science. I ask: how can we trust scientific instruments and what do we learn about when we use them? The dissertation has four parts. First, I construct a novel account of “epistemic possibility,” the possibility of knowing, that captures the dependency of knowledge on action, and I introduce the notion of “technological possibility,” which depends on the availability of material and conceptual means to bring about a desired state of affairs. I argue that, under certain circumstances, technological possibility is a condition for epistemic possibility. Second, I ask how instruments become reliable. I argue that when the material capacities and conceptual functions of a scientific instrument correspond, the instrument is a reliable component of the process of knowledge production. I then describe how the instrument design process can result in just such a correspondence. Instrument design produces the material device, a functional concept of the device revised in light of experience, a measure of the closeness of fit between material and function, and practices of trust such as calibration routines. ii Third, I ask what we learn from instruments such as those used for experimentation and simulation. I argue that in experiments, instruments function to inform us about the material capacities of the object of investigation, while in simulations, instruments function to inform us about the conceptual model of the object of investigation. Fourth, I put these philosophical distinctions into historical context through a case study of Monte Carlo simulations run on digital electronic computers in the 1940s-70s. I argue that digital electronic computers made the practice of Monte Carlo simulation technologically possible, but that the new method did not meet existing scientific standards. Consequently, Monte Carlo design practices were revised to address the worries of potential practitioners.

This dissertation is an attempt to understand the role of instruments in the process of knowledge production in science. I ask: how can we trust scientific instruments and what do we learn about when we use them? The dissertation has four parts. First, I construct a novel account of “epistemic possibility,” the possibility of knowing, that captures the dependency of knowledge on action, and I introduce the notion of “technological possibility,” which depends on the availability of material and conceptual means to bring about a desired state of affairs. I argue that, under certain circumstances, technological possibility is a condition for epistemic possibility. Second, I ask how instruments become reliable. I argue that when the material capacities and conceptual functions of a scientific instrument correspond, the instrument is a reliable component of the process of knowledge production. I then describe how the instrument design process can result in just such a correspondence. Instrument design produces the material device, a functional concept of the device revised in light of experience, a measure of the closeness of fit between material and function, and practices of trust such as calibration routines. ii Third, I ask what we learn from instruments such as those used for experimentation and simulation. I argue that in experiments, instruments function to inform us about the material capacities of the object of investigation, while in simulations, instruments function to inform us about the conceptual model of the object of investigation. Fourth, I put these philosophical distinctions into historical context through a case study of Monte Carlo simulations run on digital electronic computers in the 1940s-70s. I argue that digital electronic computers made the practice of Monte Carlo simulation technologically possible, but that the new method did not meet existing scientific standards. Consequently, Monte Carlo design practices were revised to address the worries of potential practitioners.

The thesis presents the first in-depth study of the role of measuring instruments in a leading scientific society concerned with field science. It draws upon a substantial literature in the history of science, geography, and exploration and makes use of actor network theory. The thesis considers the instruments to have been assimilated into an iterative cyclical process. By studying each aspect of the cycle, a comprehensive understanding of the integration of instruments into the working practices of the Society, the process of exploration, and ultimately the British imperialist endeavour, has been achieved. The start date is that of the founding of the Society. The end date approximates to the retirement of the map curator Edward Reeves, when recording practices at the Society changed. The century has coherence as the instruments remained essentially similar. The thesis therefore draws on a range of archival material: the journal articles, the medal awards, and the maps in addition to the paper archives, minute books and instruments themselves. The empirical findings have been enriched by reference to a substantial literature from historians of science, historical geographers and instrument historians. The thesis documents instrumental activity on behalf of the Society from acquisition to disposal or loss, regarding activity on behalf of the Society as 'added resource'. The thesis argues that the ambitions of the Society were slow to be enacted, and that a collection of instruments for lending was not formed until 1850. The preparation of travellers has been discussed as a complementary activity; systematic provision is likewise found to have been slow. Having studied fifty expeditions with respect to instrument mobilisation, from which excerpts are presented, a number of factors are identified which affected success, and the fallibility of instruments is confirmed. The itineraries of over a thousand individual items have been charted and made available in a database which will assist future research. The agencies of the instruments have been considered to be knowledge creation, individual reputation, empire, and social relations. The RGS developed strategies for militating against the fallibility of instruments in the field to provide credible outcomes. The instrumental data was manipulated by a growing body of professionals which served to moderate results. The instruments conferred social and epistemological authority to some groups more than others, but not necessarily in the manner predicted by existing theories. The geographical endeavour could be subsumed into imperialist demands. The instruments reflected and strengthened existing social hierarchies. The conclusions drawn indicate that historians of science and geography need to look at the role of instruments in more detail than extant models of knowledge creation, including ANT, suggest.

Cette thèse d’épistémologie et d’histoire des sciences cognitives est consacrée à son niveau le plus général au problème de l’instrument scientifique, parent pauvre de la réflexion sur l’investigation scientifique, et se concentre à titre particulier sur le développement des techniques d’imagerie cérébrale fonctionnelle et leur introduction dans le domaine cognitif au cours des années 1980-1990. Un choix motivé notamment par la nouveauté et l’importance de ce nouvel instrument, dont l’émergence est régulièrement comparée à celle du télescope au moment de la Révolution scientifique du XVIIe siècle. La première partie est ainsi consacrée à une analyse générale de l’instrument scientifique et des problèmes essentiels qu’il soulève. Elle propose un certain nombre d’hypothèses en réponse, et en examine les enjeux théoriques. La deuxième partie défend une interprétation historique de l’émergence des deux technologies d’imagerie fonctionnelle que sont la tomographie par émission de positons et l’imagerie par résonance magnétique fonctionnelle. En reprenant dans le détail certains éléments d’invention et de diffusion de ces techniques, elle montre notamment l’intrication des procédures de validation des instruments et des divers mécanismes scientifiques et sociétaux qui poussent à les développer puis à les utiliser. A la lumière des analyses théoriques et générales de la première, et sur la base de l’interprétation historique de la seconde, la troisième partie est dédiée à l’examen des implications de ces nouvelles technologies d’imagerie sur l’évolution du champ des sciences cognitives et de la reprise de leurs résultats dans d’autres domaines, tant scientifiques que technologiques ou pratiques. A ce double égard, elle défend la thèse générale que l’introduction de l’imagerie agit beaucoup moins comme un facteur de résolution de certaines questions que comme un facteur de déplacement de la problématique et de l’impact théorique et sociétal des sciences cognitives. / At a general level, this dissertation in philosophy and history of cognitive science is devoted to the underestimated problem of scientific instruments. It is focused on some functional brain imaging techniques introduced in the field of cognitive studies during the 1980’s and 1990’s, the impact of such new technologies being sometimes compared to an instrumental revolution, in a way similar to the impact of the invention of the telescope on post-Galilean astronomy. The first part consists in a philosophical and historical analysis of the notion of scientific instrument. In this regard, some issues are raises and some hypotheses are formulated. The second part presents an interpretation of the historical emergence of Positron Emission Tomography and functional Magnetic Resonance Imaging. Dealing with details of the invention and circulation of those techniques, it shows in particular the entanglement of the validation procedures of instruments with the various scientific and societal mechanisms driving to their development and use. Taking its roots in the general analysis of the first part and the historical interpretation of the second part, the third part looks into the impact of the new functional brain imaging technologies on the evolution of cognitive science and the diffusion of its results in other domains. Concerning both cognitive science and larger aspects, it is argued that brain imaging is less a factor of resolution of specific questions than a factor of shifting in the problematics and the theoretical and societal significance of cognitive science.

Regarder la mer comme un espace politique et social implique de dépasser les frontières et les disciplines. L’exercice est passionnant mais nécessite de rebattre les cartes. Cette thèse a ainsi comme ambitieux objectif de comprendre comment les humains observent et gèrent l’environnement marin, et comment ils parviennent, ou non, à échanger autour des représentations ainsi obtenues. Le célèbre exemple d’Antoine de Saint-Exupéry devrait suffire à donner une idée du défi à relever. Là où certains voient un chapeau d’autres imaginent un serpent boa qui digère un éléphant ; à nous, alors, de chercher à dessiner au travers de ce travail une description à la fois simple et précise des points de vue des humains sur ce qui les entoure ; des scientifiques, des décideurs et des pêcheurs sur les interactions entre pêcheries et petits cétacés dans le golfe de Gascogne puisque c’est le sujet qui nous intéresse. Nous nous sommes donc demandé comment observer les positionnements stratégiques des acteurs sur les captures accidentelles de petits cétacés dans le Golfe de Gascogne pour rétablir des relations de confiance et de dialogue entre les acteurs ? Pour répondre à cette problématique, nous avons mis en place un processus participatif d’accompagnement des acteurs pour construire une vision partagée de l’environnement marin. A l’aide de cette méthode, nous avons montré que l’environnement marin est un construit scientifique et qu’il est nécessaire de le construire politiquement et socialement pour y intégrer la complexité nécessaire à une gestion réellement durable des interactions entre activités humaines et écosystème marin. A ce titre, les instruments d’observation et de gestion de l’environnement jouent un rôle central comme nous l’expliquerons dans le cadre de cette thèse. / Looking at the sea as political and social space involves reaching across borders and disciplines. The task is thrilling but requires reshuffling the cards. Thus, this thesis ambitious objective is to understand how humans observe and manage the marine environment, and how they achieve, or not, to exchange around the obtained representations. The famous example of Antoine de Saint-Exupéry should give us an idea of the challenges to overcome. Where some see a hat, others imagine a boa snake digesting an elephant. So, in this study, our job is to draw a simple but precise description of humans’ points of view on their surroundings. More precisely, we focus on scientists, decision-makers and fishermen’s points of view on interactions between fisheries and small cetaceans in the Bay of Biscay (France). Therefore, we wondered how to observe stakeholders’ strategic positions on small cetacean bycatch in the Bay of Biscay to restore trust-based relationships and re-establish constructive dialogue among stakeholders. To answer this question, we set up a participatory process to support stakeholders in building a shared vision of the marine environment. By implementing this method, we showed that the marine environment is scientifically constructed. It also needs to be politically and socially constructed to incorporate the necessary complexity to sustainably manage interactions between human activities and marine ecosystems. As such, observation and management instruments of the marine environment play a central role as we will explain in this thesis.

J’explore de nouvelles façons d’étudier l’histoire et l’historicité de la perception, à travers un double portrait du psychologue francophone Albert Michotte, et de la collection de ses disques en papier. Leur interaction produit de nouvelles images expérimentales, éclaircissant les complexités de la perception. J’ai navigué différents archives, archives d'objets et collections d’instruments en Belgique, en France et en Allemagne. La découverte de nouvelles sources et mes ré-animations historiques m’ont permis de combiner l’histoire des sciences et l’étude des médias, touchant sur l’histoire de la philosophie et de la religion. Le portrait de Michotte dévoile une figure qui fait le pont entre différents paradigmes psychologiques, science et religion, filmologie et phénoménologie expérimentale, aussi bien qu’un diplomate des sciences traversant deux guerres, des politiques religieuses et des changements institutionnels. Etudier les paradoxes qu’il incarnait devient ainsi un outil d’historiographie. Le portrait des disques, contextualisé en termes de 'contextes d’action', montre comment ils sont liés à la pratique expérimentale, le cinéma, l’art et la culture matérielle du laboratoire. Ce double portrait montre comment Michotte et les disques créèrent ensemble des images en mouvement afin d’étudier les perceptions dynamiques, telle que la perception de la causalité. Le mouvement est essentiel à cette thèse, car il permet de comprendre comment de telles perceptions son générées et transportées. L’étude de ces perceptions permet de saisir comment la perception dépend d’un contexte, se forme à travers des inter-actions, et change – montrant son historicité. / I explore new ways to study the history and historicity of perception, through a double portrait: of the francophone psychologist Albert Michotte, and of a set of well-preserved rotating paper discs. In their interaction, new experimental images were generated, shedding light on the intricacy of perception. I have searched different archives, object-archives and instrument collections in Belgium, France and Germany. Newly discovered sources, together with my historical re-animations, allowed me to combine history of science with media studies, in close interaction with the history of philosophy and religion.The portrait of Michotte shows a bridging-figure between different psychological paradigms, science and religion, filmology and experimental phenomenology, performing science diplomacy to navigate two wars, religious politics and institutional change. Studying the paradoxes he embodied is developed into a historiographical tool. The portrait of the discs, contextualised in terms of 'action contexts', shows how they related to experimental practice, cinema, art and the material culture of the laboratory. This dynamic double portrait shows how Michotte and the discs together create moving images for the study of dynamic perceptions, such as the perception of causality. Motion is central to this thesis, not only for explaining the dynamic perception of movements, but especially for understanding how such perceptions are generated and transported. Studying these 'movement-perceptions' makes it possible to grasp how perception is context dependent, how it is shaped through inter-actions, and how it changes – giving it a history.

Mit der Bekanntgabe der Entdeckung Röntgens 1895 begann nicht nur eine massive Bildproduktion, sondern auch ein reges radiologisches Ausstellungwesen, das sich an ein medizinisch-wissenschaftliches Publikum richtete und parallel zu wissenschaftlichen Kongressen stattfand. Die vorliegende Arbeit geht dieser Praxis des Ausstellens von Röntgenbildern und -apparaten im ersten Drittel des 20. Jahrhunderts nach und bezieht die Ausstellungen auf das im Entstehen begriffene medizinisch-wissenschaftliche Feld der Radiologie. Ausstellungen waren, so die zentrale These, keine dem radiologischen Erkenntnisprozess nachfolgenden Veranstaltungen, sondern Orte, bei denen ein radiologisches Apparate- und Bildwissen kommuniziert und erzeugt wurde. In der Arbeit wird die soziale, technische und expositorische Entwicklung des radiologischen Feldes parallel erzählt und eng miteinander verflochten gedacht. So geraten die engen Kopplungen zwischen Ausstellungsraum und Röntgeninstitut und zwischen technischer Entwicklung und professionellem Selbstverständnis von Radiologen in den Blick. / With the discovery of X-rays in 1895 not only an increased image production can be observed, but also the new format of the X-ray exhibition was created. The exhibitions were mainly aimed at a medical and scientific audience and were organized parallel to scientific congresses. The work traces this practice of exhibiting X-ray images and apparatus in the first third of the 20th century and relates the exhibitions closely to the medical-scientific field of radiology that developed during this period. According to the central thesis, exhibitions were not events that took place after the genesis and development of radiological facts in the clinic or scientific institutes, but spaces where knowledge about the new apparatus and images was communicated and generated. In the work, the social, technical and exhibition-related development of the radiological field is told in parallel and thought of in close relation to each other. Using exhibitions as an example, the close links between exhibition spaces and X-ray institutes and between technical development and the professional self-image of radiologists are brought into focus.

Since its foundation between 1410 and 1414 the University of St Andrews has acquired what can be considered to be ‘artefacts of significance’. This somewhat nebulous phrase is used to denote items that have, for a variety of reasons, been deemed to have some special import by the University, and have been displayed or otherwise presented in a context in which this status has been made apparent. The types of artefacts in which particular meaning has been vested during the centuries under consideration include items of silver and gold (including the maces, sacramental vessels of the Collegiate Church of St Salvator, collegiate plate and relics of the Silver Arrow archery competition); church and college furnishings; artworks (particularly portraits); sculpture; and ethnographic specimens and other items described in University records as ‘curiosities’ held in the University Library from c. 1700-1838. The identification of particular artefacts as significant for certain reasons in certain periods, and their presentation and display, may to some extent reflect the University's values, preoccupations and aspirations in these periods, and, to some degree, its identity. Consciously or subconsciously, the objects can be employed or operate as signifiers of meaning, representing or reflecting matters such as the status, authority and history of the University, its breadth of learning and its interest and influence in spheres from science, art and world cultures to national affairs. This thesis provides a comprehensive examination of the growth and development of the University's holdings of 'artefacts of significance' from its foundation to the mid-19th century, and in some cases (especially portraits) beyond this date. It also offers insights into how the University viewed and presented these items and what this reveals about the University of St Andrews, its identity, which changed and developed as the living institution evolved, and the impressions that it wished to project.