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Successful prototype marine chronometers, developed by Harrison and others in the eighteenth century, stimulated a sector of the British watchmaking industry to supply Admiralty and commercial demand for this instrument. Chronometers, like other British-made timepieces, were constructed by an elaborate pre-industrial method of production. The instrument's static technology and extreme durability meant replacement demand was minimal, and new demand was low relative to existing stock and the industry's capacity. The First World War created a final surge of demand that left supplies far in excess of peacetime needs; and a new technology—radio transmissions of time signals—offered an alternative method of determining Greenwich time, and thus longitude, at sea.  相似文献   

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We offer a novel historical-philosophical framework for discussing experimental practice which we call ‘Generating Experimental Knowledge’. It combines three different perspectives: experimental systems, concept formation, and the pivotal role of error. We then present an historical account of the invention of the Scanning Tunnelling Microscope (STM), or Raster-Tunnelmikroskop, and interpret it within the proposed framework. We show that at the outset of the STM project, Binnig and Rohrer—the inventors of the machine—filed two patent disclosures; the first is dated 22 December 1978 (Switzerland), and the second, two years later, 12 September 1980 (US). By studying closely these patent disclosures, the attempts to realize them, and the subsequent development of the machine, we present, within the framework of generating experimental knowledge, a new account of the invention of the STM. While the realization of the STM was still a long way off, the patent disclosures served as blueprints, marking the changes that had to be introduced on the way from the initial idea to its realization.  相似文献   

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This paper points out that the provincial mechanics' institutes of England in their early years were as much the product of a general and pervasive scientific culture as they were of a particular educational movement. To this extent the institutes can be interpreted within the context of wider social and economic changes. The bulk of the paper relates to the Mechanics' Institute at Sheffield in the period 1832–50, but through this and other material it is argued that this case study deserves general consideration.  相似文献   

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Hull AJ 《Annals of science》2002,59(3):263-298
This paper traces the relationship between the food committees of the Royal Society and government during the First World War, concentrating on the period up to the resignation of Lord Devonport as first Food Controller. It argues that, in the context of a radical public science discourse emanating from some sections of the scientific community and greatly increased contacts between scientists and the government, the food scientists of the committees were moved to press for a formalization of the committees' role in food policy. The members constantly manoeuvered to achieve this aim, but also used a network of alternative channels into the heart of the policy process to get their findings translated into hard policy. In doing so, they explicitly rehearsed characteristic 'public science' arguments. In the institutional blur of wartime state-science relations, scientists often got close to the policy-making process. Post-War, the state swiftly moved to clarify the position: science was to be given more money, but was to be specifically blocked by new administrative arrangements embodied in the Haldane Report on the Machinery of Government from having any say in the core areas of general policy, the expert domain of the generalist policy-maker.  相似文献   

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The outbreak of war in 1914 found Britain unprepared for a lengthy conflict. British science and industry were particularly ill-prepared to meet the demands of static warfare. Within two years, however, mobilization had made appreciable strides, and, as Britain's munitions industries moved from crisis to confidence, Britain's chemical industry was transformed by an arsenal of ‘garrison chemists’, with skills either born of necessity or borrowed from overseas. At the same time, Britain's chemical leadership traced a path that led them from voluntarist to corporate methods, from private to public initiatives, and from individual to collective behaviours. This paper suggests four key stages in this mobilization, and hints at the significance of the war for the emergence of new sub-disciplines, for the careers of chemists, for academic-government relations in research, and for the image, status, and international position of British chemistry on the threshold of the postwar world.  相似文献   

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This paper explores the history of a unique assemblage of researchers in the geodetic and allied sciences organised at Ohio State University (OSU) in 1947 at the beginning of the Cold War. From about 1950 to 1970, the OSU geodetic sciences group was the most significant group of geodetic researchers in the world. Funded almost entirely by military and intelligence agencies, they pioneered the technologies, organised the research initiatives, ordered the data sets, and trained the generation of geodesists who eventually created the Cold War Figure of the Earth to both prosecute and prevent global nuclear war. They devised elaborate mechanisms to pursue in secrecy and isolation research that had hitherto been performed collaboratively and globally. They invented methods to maintain professional associations and protocols, both to distribute—and disguise—the fruits of their geodetic research. In accomplishing this, their work also undermined the basic hypothesis of isostasy that had been foundational to geodesy for the previous century.Fundamental progress in the geosciences and military and intelligence directives were inextricably linked during the Cold War, although the extent of their convergence has been masked by the security protocols organised to disguise it. With the declassification of key programmes underway, it is now both possible and necessary to substantially revise the history of Cold War-era geosciences and their associated technologies.  相似文献   

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In today's quantum mechanics and quantum field theory, the observable signature of a symmetry is often sought in the form of a selection rule: a missing radiation frequency, a particle that does not decay in another one, a scattering process which fails to take place. The connection between selection rules and symmetries is effected thanks to the mathematical discipline of group theory. In the present paper, I will offer an overview of how the productive synergy between selection rules and group theory came to be. The first half of the work will be devoted to the emergence of the idea of spectroscopic selection rules in the context of the old quantum theory, showing how this notion was linked with an interpretive scheme of theoretical nature which, once combined with group theory, would bear many fruits. In the second part of the paper, I will focus on the actual encounter between selection rules and group theory, and on the person largely responsible for it: Eugene Wigner. I will attempt to reconstruct the path which led Wigner, of all people, to be the agent effecting this connection.  相似文献   

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While historians have dealt with the origins of the concept of drug receptors in the work of Paul Ehrlich (1854–1915) and John N. Langley (1852–1925) as well as with some of its applications in modern pharmaceutical research, the history of the receptor theory as such has been neglected. Discussing major developments and conceptual changes in receptor theory between about 1910 and 1960 (including relevant contributions by A. V. Hill, A. J. Clark, J. H. Gaddum, E. J. Ariëns and others), this paper attempts to fill this gap in historiography. It provides a case study of the unfolding of research under a new paradigm, but it considers also contemporary criticism and scepticism. By the early 1960s, quantitative investigations of drug action and interpretations of the experimental findings in terms of the receptor concept had become constitutive of the emerging field of ‘molecular pharmacology’. Even then, however, receptors were still hypothetical entities.  相似文献   

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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.  相似文献   

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The plasmin–antiplasmin system plays a key role in blood coagulation and fibrinolysis. Plasmin and α2-antiplasmin are primarily responsible for a controlled and regulated dissolution of the fibrin polymers into soluble fragments. However, besides plasmin(ogen) and α2-antiplasmin the system contains a series of specific activators and inhibitors. The main physiological activators of plasminogen are tissue-type plasminogen activator, which is mainly involved in the dissolution of the fibrin polymers by plasmin, and urokinase-type plasminogen activator, which is primarily responsible for the generation of plasmin activity in the intercellular space. Both activators are multidomain serine proteases. Besides the main physiological inhibitor α2-antiplasmin, the plasmin–antiplasmin system is also regulated by the general protease inhibitor α2-macroglobulin, a member of the protease inhibitor I39 family. The activity of the plasminogen activators is primarily regulated by the plasminogen activator inhibitors 1 and 2, members of the serine protease inhibitor superfamily.  相似文献   

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This paper, the first of two, follows the development of theLaplace Transform from its earliest beginnings withEuler, usually dated at 1737, to the year 1880, whenSpitzer was its major, if himself relatively minor, protagonist. The coverage aims at completeness, and shows the state which the technique reached in the hands of its greatest exponent to that time,Petzval. A sequel will trace the development of the modern theory from its beginnings withPoincaré to its present form, due toDoetsch.  相似文献   

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Through 1886 to 1889 understanding of the mechanism of telephone transmission was transformed from an electrostatic and traditional view to an electrodynamic one conforming with Maxwell's scheme. Observed at the level of commercial application this painful adjustment occurred via a sequence of controversies connected with self-induction—on techniques of telephony, on electrical measurement, on lightning conductors and on matters of professional ethics—in which the parts played by evidence, by theory, and by authority were strangely mixed. The well-known confrontation of O. Heaviside and W. H. Preece was at the centre of the debate. An open division between traditionalists and progressives amongst electrical engineers was provoked, and the effectiveness of mathematical theory as against pure pragmatism at the practical level had in the end to be conceded.  相似文献   

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