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1.
Alexis Fontaine des Bertins (1704–1771) was the first French mathematician to introduce what we would now regard as results in the calculus of several variables. One example is Fontaine's theorem nF = (?F/?x)x + (?F/?y)y of 1737 for homogeneous expressions F of degree n in x and y. Many years later Fontaine indicated this particular result to have been ‘a continuation of the method of solution’ introduced by him in 1734 to solve the problem of the tautochrones. It is tempting to disregard this announcement, since the method applied to the tautochrones was a method of variations and not manifestly an exercise in the calculus of several variables. Do we have just another case of a mathematician's confusion about the origins of his earlier work? In this paper I describe Fontaine's possible intentions in his remarks.  相似文献   

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It has not been sufficiently emphasized that there existed two kinds of modification theory of colours, Aristotle's modification theory and Descartes-Hook's modification theory. This seems to have caused some confusion in the interpretation of the optical controversy between Newton and Hooke in 1672. The aim of the present paper is to prove that these two kinds of modification theory really coexisted, and on that basis to present a new interpretation of the optical controversy of 1672. The characteristics and the historical role of each of these theories will be described. Newton's colour theory was formed under the influence of Aristotle's modification theory, which had been disseminated through the work of an English Gassendist, Walter Charleton. Newton's optical theories were created not only under the influence of Descartes, as we have been often told, but also under the conspicuous influence of corpuscular philosophers.  相似文献   

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This paper discusses the emergence of new medical experimental specialties at the Medical School of Surgery (Escola Médico-Cirúrgica) and the Faculty of Medicine of Lisbon University (Faculdade de Medicina da Universidade de Lisboa) between 1897 and 1946, as a result of the activities of Marck Athias's (1875–1946) histophysiology research school. In 1897, Marck Athias, a Portuguese physician who had graduated from the Faculty of Medicine in Paris, founded a research school in Lisbon along the lines of Michael Foster's physiology research school in England and Franz Hofmeister's physiological chemistry school in Germany. His research programme was highly innovative in Portugal. Not only did it bring together many disciples and co-workers, but it branched out and created new medical specialties within Portuguese medical science. These new disciplinary areas grew out of the study of the histology of the nervous system but eventually expanded into normal and pathological histophysiology, physiological chemistry and experimental endocrinology. The esprit de corps that existed between research school members ensured the school's success and influence in various fields social and political as well as scientific. Athias's school was strongly influenced by positivist ideals and promoted a teaching and research style that sought inspiration in Humboldt's university model, thus helping to bring about a change in the dominant scientific ethos and to modernize scientific research in Portugal during the first half of the twentieth century.  相似文献   

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The DSCR1 (Adapt78) gene1 is transiently induced by stresses to temporarily protect cells against further potentially lethal challenges. However, chronic expression of the DSCR1 (Adapt78) gene has now been implicated in several pathological conditions including Alzheimer’s disease, Down syndrome and cardiac hypertrophy. Calcipressin 1 has been shown to function through direct binding and inhibition of the serine threonine protein phosphatase Calcineurin. Pharmacological inhibition of calcineurin, by the immunosuppressive drugs cyclosporin A and FK506, affects a wide variety of diseases. It is, therefore, likely that this endogenous calcineurin inhibitor, calcipressin 1, may also play a role in a variety of human diseases. 1Please note that the mammalian DSCR1 gene is also called Adapt78 or RCAN1, and its protein products have been named Calcipressin1, MCIP1 and RCAN1. A proposal to adopt a single gene name of RCAN1 and a protein name RCAN1 (for Regulator of Calcineurin) has been endorsed by the HUGO Gene Nomenclature Committee, but final approval must await agreement from a majority of researchers in the field. Received 2 March 2005; received after revision 27 May 2005; accepted 19 July 2005  相似文献   

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Hugo de Vries claimed that he had discovered Mendel's laws before he found Mendel's paper. De Vries's first ratios, published in 1897, for the second generation of hybrids (F2) were 2/3:1/3 and 80%:20%. By 1900, both of these ratios had become 3:1. These changing ratios suggest that as late as 1897 de Vries had not discovered the laws, although he asserted, from 1900 on, that he had found the laws in 1896. An Appendix details de Vries's Mendelian experiments as described in the original edition (1903) of volume two of Die Mutationstheorie, but omitted entirely from the English translation (1910).  相似文献   

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Hermann Helmholtz has often been understood to have started research under the influence of Kant, and then to have made a transition to a later mature empiricist phase. Without claiming that in 1847 Helmholtz held the same positions that he later espoused, I suggest that already in his 1847 ‘Über die Erhaltung der Kraft’ one may find important aspects of his later empiricism. I highlight the ways in which, from early on, Helmholtz turned Kant to use in developing an empirical program of inquiry into possible basic natural causes. To that end, I indicate how, throughout his arguments, Helmholtz employed, sometimes explicitly, but often tacitly, an empiricist logic, one that ran contrary to any form of transcendental deduction, and even to all a priori knowledge. Instead of deriving aspects about the ultimate constituents of nature, Helmholtz aimed to define the proper project for physical natural science. The first part of the paper describes the context of discussion in which Helmholtz entered. The bulk of the paper then analyzes Helmholtz's arguments in order to make space between (1) Kantian, and other, deductions of characteristics that must be true of nature and (2) Helmholtz's delineation of empirically determinable characteristics of presumed ultimate elements of nature, ones that he meant to be specified and delimited through future experimental research. The paper highlights that throughout his discussion Helmholtz meant to define the proper project for physical natural science, a project rife with empiricist aspects.  相似文献   

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It is with good reason that the name Rutherford is closely linked with the early history of the alpha particle. He discovered them, determined their nature, and from 1909 used them to probe the structure of the atom. From 1898 to 1902 Rutherford construed alpha radiation as a type of non-particulate Röntgen radiation. On his theory of the locomotion of radioactive particles Rutherford proposed that alpha radiation consisted of negatively charged particles. During 1902 he confirmed the particulate nature of alpha radiation but discovered that these alpha particles were positively charged. Although Rutherford suspected from 1903 that these alpha particles were related somehow with helium, the proof required six long years of investigation. By mid-1908 it seemed certain that the alpha particle possessed two units of the elementary charge. Since the e/m ratio had already been determined for alpha particles, this evidence enhanced the suspected connection with helium. However, this gain and loss of charge was still construed as an ionization effect. Since as late as 1908 gaseous ionization was assumed to involve the gain or loss of a single unit of charge, Rutherford's alleged case of doubly ionized alpha particles was presumably an exception. Yet helium was known to be an inert gas and thus hardly a likely candidate for such exceptional ionization behaviour. To establish the connection, therefore, Rutherford resorted to a spectroscopic test. He collected spent alpha particles shot into a thin glass tube and gradually observed the spectrum of helium. Rutherford had thus been correct in his assumption, but a proper explanation was possible only after the confirmation of the nuclear structure of the atom.  相似文献   

10.
On the basis of a significant number of unpublished documents, here published for the first time, the article reconstructs the historical and scientific origins of Lavoisier's Mémoires de physique et de chimie. Because of the paucity of primary sources available so far, this work has previously received little attention and its 'publication' is commonly attributed to Madame Lavoisier's effort to revive the memory of her husband. In contrast with this image, this article suggests that Madame Lavoisier had only a subsidiary role and that Armand Séguin's contribution to both the editing and the scientific organization of the Mémoires needs a historical reassessment. Lavoisier's collaboration with Séguin, dating from 1792, resulted in a work the aim of which was far more ambitious than that of collecting already published memoirs. Furthermore, it is argued that the contents of the first volume of the Mémoires indicate an important evolution in Lavoisier's chemical theory.  相似文献   

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The reception of Buffon's Histoire Naturelle in the Enlightenment has not received the historical attention it deserves. Drawing primarily on archival sources, this paper examines Aberdeen reactions to the Histoire during the period c. 1750–1800. As pedagogues, the Aberdonians endeavoured to maintain intellectual orthodoxy, and hence they attacked Buffon for his apparent materialism and atheism. Moreover, the Aberdonians rejected Buffon's critique of taxonomy because they based their natural history courses on classifications of the three kingdoms of nature, and because they attempted to use classification systems in nosology and the study of the human mind. Finally, in the 1790s Aberdeen readings of the Histoire were profoundly affected by the fears aroused by the French Revolution.  相似文献   

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Early geological investigations in the St David's area (Pembrokeshire) are described, particularly the work of Murchison. In a reconnaissance survey in 1835, he regarded a ridge of rocks at St David's as intrusive in unfossiliferous Cambrian; and the early Survey mapping (chiefly the work of Aveline and Ramsay) was conducted on that assumption, leading to the publication of maps in 1845 and 1857. The latter represented the margins of the St David's ridge as ‘Altered Cambrian’. So the supposedly intrusive ‘syenite’ was regarded as younger, and there was no Precambrian. These views were challenged by a local doctor, Henry Hicks, who developed an idea of the ex-Survey palaeontologist John Salter that the rocks of the ridge were stratified and had formed a Precambrian island, round which Cambrian sediments (now confirmed by fossil discoveries) had been deposited. Hicks subsequently proposed subdivision of his Precambrian into ‘Dimetian’, ‘Pebidian’, and (later) ‘Arvonian’, and he attempted correlations with rocks in Shropshire, North Wales, and even North America, seeking to develop the neo-Neptunist ideas of Sterry Hunt. The challenge to the Survey's work was countered in the 1880s by the Director General, Geikie, who showed that Hicks's idea of stratification in the Dimetian was mistaken. A heated controversy developed, several amateur geologists, supported by a group of Cambridge Sedgwickians, forming a coalition of ‘Archaeans’ against the Survey. Geikie was supported by Lloyd Morgan. Attention focused particularly on Ogof Lle-sugn Cave and St Non's Arch, with theory/controversy-ladenness of observations evident on both sides. Evidence from an eyewitness student record of a Geological Society meeting reveals the ‘sanit`ized’ nature of the official summary of the debate in QJGS. Field mapping early in the twentieth century by J. F. N. Green allowed a compromise consensus to be achieved, but Green's evidence for unconformity between the Cambrian and the Dimetian, obtained by excavation, can no longer be verified, and his consensual history of the area may need revision. Unconformity between the Cambrian and the Pebidian tuffs is not in doubt, however, and Precambrian at St David's is accepted. The study exhibits features of geological controversy and the British geological community in the nineteenth century. It also furnishes a further instance of the great influence of Murchison in nineteenth-century British geology and the side-effects of his controversy with Sedgwick.  相似文献   

14.
This paper presents the main features of the treatise on magnetism written by the Jesuit Leonardo Garzoni (1543–92). The treatise was believed to be lost, but a copy of it has been recently recovered. The treatise is briefly described and analysed. The results of a comparison between Garzoni's treatise, Della Porta's Magia Naturalis (1589), and Gilbert's De Magnete (1600) are also summarized. As claimed in the seventeenth century by Niccolò Cabeo and Niccolò Zucchi, the treatise contains quite a lot of the material to be found subsequently in the Magia Naturalis and in the De Magnete. Most importantly, the treatise presents so many interesting features, well before Gilbert's work, which make it the first example of a modern treatment of magnetic phenomena.  相似文献   

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John Case (d. 1600), the most important English Aristotelian of the Renaissance period, has not yet received the attention he deserves. In his Lapis philosophicus (Oxford, 1599), an exposition of Aristotle's Physics, is found a discussion of the relation of nature to art which parallels in many ways that formulated a few years later in the writings of Francis Bacon. Case argues, in a way more reminiscent of the works of Giambattista della Porta than of those of Aristotle, that the natural philosopher can legitimately apply the productive arts in helping nature to fulfill her function. Moreover, while rejecting the excessive claims of the Paracelsians, Case does accept the transmutational claims of the alchemists. In the final analysis, his ‘Aristotelianism’ has been tempered by the tradition of Renaissance natural magic. Like many other Peripatetic thinkers of the period, Case shows himself to be an eclectic, drawing materials from a wide variety of sources and open to many of the new scientific tendencies then developing.  相似文献   

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In this paper, I introduce a new historical case study into the scientific realism debate. During the late-eighteenth century, the Scottish natural philosopher James Hutton made two important successful novel predictions. The first concerned granitic veins intruding from granite masses into strata. The second concerned what geologists now term “angular unconformities”: older sections of strata overlain by younger sections, the two resting at different angles, the former typically more inclined than the latter. These predictions, I argue, are potentially problematic for selective scientific realism in that constituents of Hutton's theory that would not be considered even approximately true today played various roles in generating them. The aim here is not to provide a full philosophical analysis but to introduce the case into the debate by detailing the history and showing why, at least prima facie, it presents a problem for selective realism. First, I explicate Hutton's theory. I then give an account of Hutton's predictions and their confirmations. Next, I explain why these predictions are relevant to the realism debate. Finally, I consider which constituents of Hutton's theory are, according to current beliefs, true (or approximately true), which are not (even approximately) true, and which were responsible for these successes.  相似文献   

18.
This paper aims first and foremost to unravel and clarify an interesting 17th century controversy around superposition in projectiles, which allegedly existed between the French Jesuit Honoré Fabri and the Italian physicist and astronomer Giovanni Alfonso Borelli. This conflict – initially described by the English mathematician John Wallis in a letter from 1670 to the secretary of the Royal Society – has been erroneously identified with Fabri's Dialogi physici (1669), a work written in response to Borelli's De vi percussionis (1669). In fact, this “conflict” was nothing but Wallis's account of a contradiction between Borelli's above mentioned work and Fabri's Tractatus physicus de motu locali from 1646, while Fabri's 1669 work expressed views very different from those contained in his Tractatus physicus. I will try here to reconstruct Fabri's change of heart between 1646 and 1669 concerning projectiles and superposition, while tracing the real bone of contention between (the later) Fabri and Borelli – superimposing contrary motions – to its Aristotelian origins. My analysis will lead me to problematize the way modern historians usually interpret the relation between Aristotle's physical thinking and projectile theories of early modern theoreticians (e.g. Nicollò Tartaglia's).  相似文献   

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SUMMARY

As the Enlightenment drew to a close, translation had gradually acquired an increasingly important role in the international circulation and transmission of scientific knowledge. Yet comparatively little attention has been paid to the translators responsible for making such accounts accessible in other languages, some of whom were women. In this article I explore how European women cast themselves as intellectually enquiring, knowledgeable and authoritative figures in their translations. Focusing specifically on the genre of scientific travel writing, I investigate the narrative strategies deployed by women translators to mark their involvement in the process of scientific knowledge-making. These strategies ranged from rhetorical near-invisibility, driven by women's modest marginalization of their own public engagement in science, to the active advertisement of themselves as intellectually curious consumers of scientific knowledge. A detailed study of Elizabeth Helme's translation of the French ornithologist François le Vaillant's Voyage dans l'intérieur de l'Afrique [Voyage into the Interior of Africa] (1790) allows me to explore how her reworking of the original text for an Anglophone reading public enabled her to engage cautiously – or sometimes more openly – with questions regarding how scientific knowledge was constructed, for whom and with which aims in mind.  相似文献   

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