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1.
In his Harmonics, Ptolemy constructs a complex set of theoretically ‘correct’ forms of musical scale, represented as sequences of ratios, on the basis of mathematical principles and reasoning. But he insists that their credentials will not have been established until they have been submitted to the judgement of the ear. They cannot be audibly instantiated with the necessary accuracy without the help of specially designed instruments, which Ptolemy describes in detail, discussing the uses to which each can be put and cataloguing its limitations. The best known of these instruments is the monochord, but there are several more complex devices. This paper discusses one such instrument which is known from no other source, ancient or modern, whose design was prompted by the geometrical construction known as the helikôn. It has several remarkable peculiarities. I examine its design, its purposes, and the merits and shortcomings which Ptolemy attributes to it. An appendix describes an instrument I have built to Ptolemy’s specifications (possibly the first of its kind since the second century bc), in an attempt to find out how satisfactorily such a bizarre contraption will work; and it explains how various practical problems can be resolved.  相似文献   

2.
3.
Isaac Newton's closest approach to a system of the world in the critical period 1681–84 is provided in a set of untitled propositions concerning comets. They drastically revise his position maintained against Flamsteed in 1681 and may signal his adoption of a single comet solution for the appearances of 1680/1. Points of agreement and difference with the key pre-Principia texts of 1684–85 are analysed. He shows substantial control of the phenomena of tails which change very little in mechanical detail throughout his subsequent work. An emerging theory of gravitation brings planets, their satellites, and comets under the same laws of motion, yet retains a celestial vortex and includes a singular proposition in lieu of the usual formulation of Keplers area law. The analysis raises questions on a number of issues of recent Newtonian scholarship ranging from his achievement following his correspondence with Robert Hooke in 1679 to his veneration of the wisdom of the ancients. (Received September 7, 1999)  相似文献   

4.
The life and career of Lorenz Spengler (1720–1807) provides evidence to support the view that the eighteenth century was a period when there was a fruitful interrelationship between the arts, crafts, and sciences in the courts and capitals of Europe. Spengler was trained as a turner, and was appointed teacher of ornamental turning to the Danish royal family and turner of the court in 1745. Even in the early years of his artistic career Spengler was interested in electricity and its role in healing, and he became an avid collector of shells and naturalia. Over the years, Spengler's interests turned more to the natural sciences, and in 1771 he was appointed director of the King's Kunstkammer. Only by considering both aspects of Spengler's career can his scientific activities be placed in their proper historical context.  相似文献   

5.
The characteristics of inductivist historiography of science, as practised by earlier scientist/historians, and Whig historiography, as practised by earlier political historians, are described, according to the accounts of Agassi and Butterfield. It is suggested that the writings of Geikie on the history of geology allow us to characterize him as a Whig/inductivist historian of science who formulated anachronistic judgements. It is further suggested that his writings have had a considerable long-term effect on interpretations of the history of geology. The character of Geikie's historiography is related to his social, political and religious views, his historicism, and his romantic enthusiasm for Nature. His methodological pronouncements are examined: he believed that the present is the key to the past, and also that the past is the key to the present. He was an empiricist and inductivist. These epistemological and methodological views impinged on his historiography of science. If one attempts to criticize Geikie's historiography, though one may try to judge his work according to the norms of his own day and age, historical anachronism cannot be avoided entirely and one may oneself be charged with acting ‘Whiggishly’. Historians of science, in the process of professionalization, have accepted the historiographical norms of general historians (perhaps for socio-economic reasons), but in so doing have inherited a problem that arises whenever they contemplate earlier historical writings. It is suggested that there may be more room for Whiggish historiography of science than is presently deemed acceptable. Alternatively, one may wish to draw a careful distinction between science and its meta-discipline, the historiography of science. Whig historiography conflates the two, and the work of Geikie (a scientist/historian par excellence) provides a good illustration of this.  相似文献   

6.
This paper reconceptualizes Thomas Clifford Allbutt's contributions to the making of scientific medicine in late nineteenth-century England. Existing literature on Allbutt usually describes his achievements, such as his design of the pocket thermometer and his advocacy of the use of the ophthalmoscope in general medicine, as independent events; and his work on the development of comparative pathology is largely overlooked. In this paper I focus on this latter aspect. I examine Allbutt's books and addresses and claim that Allbutt argued for the centrality of comparative pathology in the advancement of medical knowledge. He held that diseases should be studied as biological phenomena and that medicine should be made a biological science. He also argued that comparative pathology should be based upon the idea of evolution, and its study should embrace other nineteenth-century sciences including neurology, embryology and bacteriology. Allbutt's writings reveal that his endorsement of comparative pathology (1880s to 1920s), his promotion of the use of the ophthalmoscope and the thermometer in clinical medicine (early 1870s), and his support of the hospital unit system (1910s to 1920s) were part of a single programme. All were grounded in his scientific vision of medicine which emphasized a research culture, a stringent nosological attitude and an integration of laboratory sciences and clinical medicine.  相似文献   

7.
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   

8.
Adriaan van Roomen published an outline of what he called a Mathesis Universalis in 1597. This earned him a well-deserved place in the history of early modern ideas about a universal mathematics which was intended to encompass both geometry and arithmetic and to provide general rules valid for operations involving numbers, geometrical magnitudes, and all other quantities amenable to measurement and calculation. ‘Mathesis Universalis’ (MU) became the most common (though not the only) term for mathematical theories developed with that aim. At some time around 1600 van Roomen composed a new version of his MU, considerably different from the earlier one. This second version was never effectively published and it has not been discussed in detail in the secondary literature before. The text has, however, survived and the two versions are presented and compared in the present article. Sections 1–6 are about the first version of van Roomen’s MU the occasion of its publication (a controversy about Archimedes’ treatise on the circle, Sect. 2), its conceptual context (Sect. 3), its structure (with an overview of its definitions, axioms, and theorems) and its dependence on Clavius’ use of numbers in dealing with both rational and irrational ratios (Sect. 4), the geometrical interpretation of arithmetical operations multiplication and division (Sect. 5), and an analysis of its content in modern terms. In his second version of a MU van Roomen took algebra into account, inspired by Viète’s early treatises; he planned to publish it as part of a new edition of Al-Khwarizmi’s treatise on algebra (Sect. 7). Section 8 describes the conceptual background and the difficulties involved in the merging of algebra and geometry; Sect. 9 summarizes and analyzes the definitions, axioms and theorems of the second version, noting the differences with the first version and tracing the influence of Viète. Section 10 deals with the influence of van Roomen on later discussions of MU, and briefly sketches Descartes’ ideas about MU as expressed in the latter’s Regulae.  相似文献   

9.
The trefoil factor family (TFF) comprises a group of small peptides which are highly expressed in tissues containing mucus-producing cells – especially in the mucosa lining the gastrointestinal tract. The peptides seem crucial for epithelial restitution and may work via other pathways than the conventional factors involved in restitution. In vitro studies have shown that the TFFs promote restitution using multiple mechanisms. The peptides also have other functionalities including interactions with the immune system. Moreover, therapeutic effects of the TFFs have been shown in several animal models of gastrointestinal damage. Still it is not clear which of their in vitro properties are involved in the in vivo mode of action. This review describes the TFF family with emphasis on their biological properties and involvement in mucosal protection and repair. Received 10 October 2008; received after revision 07 November 2008; accepted 10 November 2008  相似文献   

10.
This article ventures a reappraisal of Huxley's role in the Darwinian debates. First, the views on life-history held by Huxley before 1859 are identified. Next, the disharmony between these views and the view put forward by Darwin in the Origin of species (1859) is discussed. Huxley's defence of the Origin is then reviewed in an effort to show that, despite his fervour on Darwin's behalf, his advocacy of the case for natural selection was not particularly compelling, and that his own scientific work took no revolutionary new direction after 1859.  相似文献   

11.
Descartes is always concerned about knowledge. However, the Galileo affair in 1633, the reactions to his Discourse on method, and later his need to reply to objections to his Meditations provoked crises in Descartes’s intellectual development the import of which has not been sufficiently recognized. These events are the major reasons why Descartes’s philosophical position concerning how we know and what we may know is radically different at the end of his life from what it was when he began. We call this later position Descartes’s epistemic stance and contrast it with his earlier methodological, metaphysical realism. Yet Descartes’s epistemic views cannot be separated from other aspects of his work, for example, his views concerning God, causality, metaphysics, and the nature of science. A further meta-implication is that serious errors await any scholar who cites early Cartesian texts in support of late Cartesian positions, or who uses later texts in conjunction with early ones to support a reading of Descartes’s philosophy.  相似文献   

12.
Summary Scarites occidentalis has 2n=41 (females 2n=42), n=19+X1X2Y. This multiple sex-chromosome system and other karyotypic characteristics suggest that this species andS. buparius share a recent common ancestor in which the sex trivalent was probably originated.Thanks are due to Dr N. Virkki for his valuable comments and his help with the English, to Dr Ramos and Dr Aparicio for discussion and advice, to Dr F. Hiraldo and M. Mañez for collecting the specimens. This work has been supported by a postdoctoral fellowship of the Consejo Superior de Investigaciones Científicas.  相似文献   

13.
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   

14.
Summary The mechanism of the in vitro inhibition of Ca2+-, phosphatidylserine-dependent protein kinase C (PK-C)2 by the purifiedholo (ligand-saturated) forms of cellular retinol-binding protein (cRBP) and cellular retinoic acid-binding protein (cRABP) was studied. We report here that i) the PK-C-inhibitory action ofholo-cRBP andholo-cRABP is due to their respective ligands, all-trans-retinol and all-trans-retinoic acid; ii) the reduced phosphorylation of theholo-retinoid-binding proteins and brain cytosolic proteins is not the result of a retinoid-induced soluble phosphatase or protease activity; iii) retinoids reduce PK-C affinity for calcium and phosphatidylserine in vitro; and iv) the structure-function activity of the retinoids and the specific interaction of these effect of retinoids on plasma membrane-associated PK-C activity pays a significant role in defining the early epigenetic aspects of PK-C-dependent tumor promotion and may be a physiological mechanism by which retinoids induce terminal differentiation in cell types that do not express soluble retinoid-binding proteins.We would like to thank Dr L.M. De Luca (NIH, USA) for his contribution of retinylphosphate, Dr H.N. Bhagavan (Hoffmann-La Roche) for his contribution of the arotinoids, and Merrill-Dow Corp. for their contribution of difluoromethylornithine. This work was supported by NIH Grants CA-34968, CA-07175, CA-22484, and CA-09020.  相似文献   

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16.
《Annals of science》2012,69(3):375-393
Abstract

Thanks to the efforts made in the first decade of the 18th century by Réaumur and, to a lesser extent, by Buffon, glassmaking attracted the attention of Academic French scientists. In the early 1750s, in order to bridge the gap between the protected system of French glass manufactories and the academic thirst for innovation and technological improvement, technical experts with solid scientific backgrounds were charged by the Académie des sciences to supervise the organisation of several royal manufactories. Paul Bosc d'Antic was chosen in 1755 to solve the problems at the mirror manufactory in Saint-Gobain. Bosc d'Antic's career, in its tension between his ambition as an academic author and drive as a technical inventor, and the economic interest of a free entrepreneur, provides an interesting example of the complex and contradictory evolution of the French chemical arts and manufactories during the second half of the 18th century.

“Les arts ont entr'eux des rapports plus ou

moins marqués, […] mais celui de la verrerie

est le fondement de presque tous les autres”.

Bosc d'Antic  相似文献   

17.
In the late eighteenth and early nineteenth centuries the Polish geoscientist, philosopher, and statesman Stanis?aw Staszic (1755–1826) conducted an extensive geological survey of Poland and adjacent areas. In 1815, he completed a book (in Polish), On the geology of the Carpathians and other mountains and lowlands of Poland, complemented by a well-made geological map of Central and Eastern Europe. Early in the nineteenth century, Staszic refined the idea of ‘geological mapping’, though initially he was interested in the exploration of mineral deposits, rock salt, copper and iron ores, and coal. Unlike his predecessors, his book adopted a temporal subdivision of rocks, using a somewhat modified version of Abraham Gottlob Werner's system. He delineated the surface distribution of five rock units and coloured them onto his map. His work gave expression to his view of geological history, and brought the ‘Enlightenment Period’ of geology in Central and Eastern Europe to a close.  相似文献   

18.
In the history of chemistry, the Danish chemist Julius Thomsen (1826–1909) is best known for his contributions to thermochemistry. Throughout his life, he was a pronounced atomist and a tireless advocate of neo-Proutian views as to the constitution of matter. On many occasions, especially in his later years, he engaged in speculations concerning the unity of matter and the complexity of atoms. In this engagement, Thomsen was alone in Danish chemistry, but his works were representative of a large number of 19th-century chemists, particularly in England and Germany. Thomsen's ideas as to the constitution of matter, the periodic system and the noble gases, may be seen as typical of this vigorous trend in fin de siècle chemistry.  相似文献   

19.
Summary The pressure responses of phase II larvae of the lobster,Homarus gammarus, are not affected by Cetavlon cetrimide, nor by other surface active substances. Amputation of the first and second antennae indicates that these structures, like the embryonic statocyst are essential neither for the perception of the pressure stimulus, nor for the orientation of the response.This work was carried out while at the Marine Biological Station, Port Erin, Isle of Man. It is a pleasure to acknowledge the hospitality of the Director and his staff.  相似文献   

20.
The reception process of Aristotle's Mechanical Questions during the early modern period began with the publication of the corpus aristotelicum between 1495 and 1498. Between 1581 and 1627, two of the thirty-five arguments discussed in the text, namely Question XIV concerning the resistance to fracture and Question XVI concerning the deformation of objects such as timbers, became central to the work of the commentators. The commentaries of Bernardino Baldi (1581–1582), Giovanni de Benedetti (1585), Giuseppe Biancani (1615) and Giovanni di Guevara (1627) gradually approached the doctrine of proportions of the Renaissance architects, some aspects of which deal with the strength of materials according to the Vitruvian conception of scalar building. These aspects of the doctrine of proportions were integrated into the Aristotelian arguments so that a theory of linear proportionality concerned with the strength of materials could be formulated. This very first theory of strength of materials is the theory to which Galileo critically referred in his Discorsi where he published his own theory of strength of materials. Economic and military constraints are determined as the fundamental reasons for the commentators’ commitment to developing a theory of strength of materials that later linked Galileo's work to the practical knowledge of the architects and machine-builders of his time.  相似文献   

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