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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   

3.
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   

4.
It has been and still is commonly believed by geologists and historians of geology alike that geological theory is an extrapolation from the empirical knowledge of the geology of a region. Abraham Gottlob Werner (1749–1817), whose theory concerning the origin of basalt and the minor role of volcanoes and the major role of water in the history of the earth's crust was eventually proven wrong in some respects, is usually cited as the prime example of a geologist who had not ventured beyond the confines of his native region, Saxony, and had developed a universal geological theory based almost entirely on his observations of that region. In this essay I show that the geology of Saxony played a relatively unimportant role in the development of Werner's universal geological theory; that he became a neptunist before he had closely examined the geology of Saxony; and that his explanation of the history of the earth's crust was as reasonable, if not more reasonable, than the explanations brought forth by those of his contemporaries who opposed his views.  相似文献   

5.
Summary The biological interaction between cadmium and copper has been studied. Cadmium uptake of KB cells was specifically inhibited by the addition of copper ions to the culture medium. Cadmium which had already been taken up by the cells was released following the addition of copper ions.The authors are grateful to Dr. M. Ishizawa for his helpful discussion.  相似文献   

6.
The publication in 1906 of Alexander Smith's Introduction to general inorganic chemistry inaugurated a decisive change in chemical pedagogy in the US, the effects of which are still evident. The nature and extent of Smith's innovations are described through a comparison of his text to its source material and contemporaries. His authoritative command of and whole-hearted commitment to the intellectual framework of Ionist physical chemistry set his text apart from its American competitors, while his efforts to make the tools of physical chemistry immediately useful to his readers distinguished it from its most immediate source material, Wilhelm Ostwald's Grundlinien der anorganischen Chemie. Smith's curricular innovations in chemistry were a practical expression of his radically restrictive view of the social role of collegiate education, which he conceived as solely of use for its ability to prepare students for professional life. During the fifteen years prior to the publication of his groundbreaking textbook, Smith underwent two critical, formative experiences. First, he retreated intellectually from the structural organic chemistry in which he was trained, ultimately adopting a professional identity as a physical inorganic chemist. His involvement in the controversy regarding the structure of 1,3-diketones reveals much about his reasons for eventually abandoning organic chemistry. Second, he served the National Education Association as chairman of the Sub-committee on College Entrance Requirements in Chemistry, in the process making a close study of the ends and methods of secondary and collegiate education. These experiences made him unique among proponents of physical chemistry in the US, and help account for the unique nature of his contributions to the development of the chemical professions.  相似文献   

7.
Henri Poincaré acquired a reputation in his lifetime for being difficult to read. It was said that he missed out important steps in his arguments, assumed the truth of claims that would be difficult if not impossible to prove, and in short that he lacked rigour. In the years after his death this view coalesced into an exaggerated claim that his work was simply too vague, and has become a cliché. This paper argues that Poincaré was far from indifferent to rigour, and that what characterises his work is an attempt to convey a particular sense of what it is to understand a topic. Throughout his working life Poincaré was concerned to promote the understanding of many domains of mathematics and physics. This is as apparent in his views about geometry, his conventionalism, and his theory of knowledge, as it is in his work on electricity and optics, on number theory, and function theory. It is one of the ways Poincaré discharged his responsibilities as a scientist, and that it accounts not only for a surprising degree of unity in his work but also gives it its distinctive character—at once profound and elusive.  相似文献   

8.
Einstein proclaimed that we could discover true laws of nature by seeking those with the simplest mathematical formulation. He came to this viewpoint later in his life. In his early years and work he was quite hostile to this idea. Einstein did not develop his later Platonism from a priori reasoning or aesthetic considerations. He learned the canon of mathematical simplicity from his own experiences in the discovery of new theories, most importantly, his discovery of general relativity. Through his neglect of the canon, he realised that he delayed the completion of general relativity by three years and nearly lost priority in discovery of its gravitational field equations.  相似文献   

9.
This article explores the impact of 16th and 17th-century developments in micrometry on the methods Antoni van Leeuwenhoek employed to measure the microscopic creatures he discovered in various samples collected from his acquaintances and from local water sources. While other publications have presented Leeuwenhoek's measurement methods, an examination of the context of his techniques is missing. These previous measurement methods, driven by the need to improve navigation, surveying, astronomy, and ballistics, may have had an impact on Leeuwenhoek's methods. Leeuwenhoek was educated principally in the mercantile guild system in Amsterdam and Delft. He rose to positions of responsibility within Delft municipal government. These were the years that led up to his first investigations using the single-lens microscopes he became expert at creating, and that led to his first letter to the Royal Society in 1673. He also took measures to train in surveying and liquid assaying practices existing in his time, disciplines that were influenced by Pedro Nunes, Pierre Vernier, Rene Descartes, and others. While we may never know what inspired Leeuwenhoek's methods, the argument is presented that there were sufficient influences in his life to shape his approach to measuring the invisible.  相似文献   

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This article traces the origins of Kenneth Wilson's conception of effective field theories (EFTs) in the 1960s. I argue that what really made the difference in Wilson's path to his first prototype of EFT are his long-standing pragmatic aspirations and methodological commitments. Wilson's primary interest was to work on mathematically interesting physical problems and he thought that progress could be made by treating them as if they could be analyzed in principle by a sufficiently powerful computer. The first point explains why he had no qualms about twisting the structure of field theories; the second why he divided the state-space of a toy model field theory into continuous slices by following a standard divide-and-conquer algorithmic strategy instead of working directly with a fully discretized and finite theory. I also show how Wilson's prototype bears the mark of these aspirations and commitments and clear up a few striking ironies along the way.  相似文献   

12.
I reappraise in detail Hertz's cathode ray experiments. I show that, contrary to Buchwald's (1995) evaluation, the core experiment establishing the electrostatic properties of the rays was successfully replicated by Perrin (probably) and Thomson (certainly). Buchwald's discussion of ‘current purification’ is shown to be a red herring. My investigation of the origin of Buchwald's misinterpretation of this episode reveals that he was led astray by a focus on what Hertz ‘could do’—his experimental resources. I argue that one should focus instead on what Hertz wanted to achieve—his experimental goals. Focusing on these goals, I find that his explicit and implicit requirements for a successful investigation of the rays’ properties are met by Perrin and Thomson. Thus, even by Hertz's standards, they did indeed replicate his experiment.  相似文献   

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Summary In view of the striking similarities noted in the subsection A, B, C we are bound to conclude that Euctemon was influenced by Babylonian astronomy. However, his parapegma was not just a translation of a Babylonian text: it was an improvement in many respects. His dates of annual risings and settings were more accurate than the Babylonian dates. In most cases he recorded true risings, or he recorded both the true and the visible phaenomena. This distinction is not made in the text MUL APIN.  相似文献   

15.
In November 1875, Thomas Edison made the sensational announcement that he had discovered a new force of nature, etheric force. It was to emerge some years later that the phenomenon Edison described was a form of wireless transmission, but Edison failed both to advance his theory and to exploit his discovery in new inventions. I contrast Edison’s approach to doing science with what he did when inventing, and also with the approach used by his principal scientific opponents. This contrast reveals that he failed, not so much because he was an inventor who did science badly, but because when he ventured into scientific theory-making he abandoned key techniques that made him America’s most successful inventor. From this I argue that we can identify artefact creation processes in science that parallel the process of invention, and that Edison failed because his opponents created better artefacts.  相似文献   

16.
This paper aims to show that the development of Feyerabend's philosophical ideas in the 1950s and 1960s largely took place in the context of debates on quantum mechanics.In particular, he developed his influential arguments for pluralism in science in discussions with the quantum physicist David Bohm, who had developed an alternative approach to quantum physics which (in Feyerabend's perception) was met with a dogmatic dismissal by some of the leading quantum physicists. I argue that Feyerabend's arguments for theoretical pluralism and for challenging established theories were connected to his objections to the dogmatism and conservatism he observed in quantum physics.However, as Feyerabend gained insight into the physical details and historical complexities which led to the development of quantum mechanics, he gradually became more modest in his criticisms. His writings on quantum mechanics especially engaged with Niels Bohr; initially, he was critical of Bohr's work in quantum mechanics, but in the late 1960s, he completely withdrew his criticism and even praised Bohr as a model scientist. He became convinced that however puzzling quantum mechanics seemed, it was methodologically unobjectionable – and this was crucial for his move towards ‘anarchism’ in philosophy of science.  相似文献   

17.
For more than 50 years the Guy's Hospital physician Frederick Pavy (1829-1911) attempted to discredit the theory of his erstwhile teacher, Claude Bernard, that liver glycogen was broken down to supply sugar to the systemic circulation. His opposition was driven by his clinical perceptions and was based on two assumptions: the first was that the kidney was a simple filter through which small molecules would diffuse, so that sugar had to be prevented from reaching the systemic circulation. For Pavy, the liver was the barrier. The second was teleological: he could not believe that nature would operate in what he saw as a defective way, i.e. converting sugar into glycogen and then back again. At the beginning of his long working life Pavy regarded himself as a physiologist and was critical of the stagnancy of English physiology which was kept afloat by amateurs like himself in whatever time they could spare from busy private practice. At the end he came to see his own view of carbohydrate metabolism as symbolic of the schism between responsible clinicians (himself) and irresponsible daydreaming physiologists (his opponents).  相似文献   

18.
Five recently discovered letters written by James Ferguson, FRS (1710–1776) while he was on a lecture tour in 1771 add substantially to what was previously known about his activities at that time. Together with newspaper advertisements and other correspondence, they not only enable his itinerary to be reconstructed in also reveal some of his own thoughts at the time and the difficulties that he had to contend with. On this particular tour, Ferguson was away from his London base for at least seven months, visiting Birmingham, Kidderminster, Worcester, Newcastle-under-Lyme, Cheadle (Staffs.), and Derby. During this period he delivered his course of 12 lectures on Experimental Philosophy at least eight times. Amongst the people that he met were Matthew Boulton, Josiah Wedgwood, and John Whitehurst, as well as the recipient of the letters, James Beresford of Bewdley, Worcestershire.

In this paper the opportunity has been taken to present also an outline of the gradual evolution of Ferguson's lecturing career, leading up to his situation in the 1770s, as much of the relevant source material now available was unknown to his nineteenth-century biographer, Ebenezer Henderson.  相似文献   

19.
Well-known in his day, but overlooked since, Erasmus King lectured in natural and experimental philosophy from the 1730s until 1756 at his Westminster home and twenty other venues, publicizing his frequent courses exclusively in the Daily Advertiser. In 1739 he escorted Desaguliers's youngest son to Russia, hoping to demonstrate experimental philosophy to the Russian empress. En route, he conducted trials with a sea-guage in the Baltic which were reported by Stephen Hales in his Statical Essays. Various sources testify to King's subsequent experimental research for Hales in the fields of anatomy, respiration and electricity. There is recorded evidence for the exceptional range and quality of King's scientific apparatus and models.  相似文献   

20.
Archive for History of Exact Sciences - Johannes Kepler dedicated much of his work to discover a law for the refraction of light. Unfortunately, he formulated an incorrect law. Nevertheless, it was...  相似文献   

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