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1.
Diffraction gratings have contributed enormously to modern science. Although some historians have written about them, there is much more to be brought to light. This paper discusses their development and use in the period up to about 1880 before Rowland began to produce them. Rittenhouse described the action of a diffraction grating in 1786, but no explanation was possible until the wave theory of light was developed. Fraunhofer discovered the dark lines in the solar spectrum in 1814, and then investigated diffraction, producing the first ruled gratings, making detailed measurements and calculating the wavelengths of prominent spectral lines. After Bunsen and Kirchhoff showed the association between spectral lines and chemical elements there was an upsurge of interest in measuring wavelengths. The gratings used in this work almost all came from one source, a relatively unknown instrument maker called Nobert, who made them by an extremely laborious process using a machine he had built himself. The most significant wavelength measurements were made by Ångström, but Mascart, Van der Willigen, Stefan, Ditscheiner and Cornu also did important work. Nobert gratings were investigated by Quincke, copied photographically by Rayleigh, and were known and discussed in the USA. Nobert's work helped to advance spectroscopy much more than has been acknowledged.  相似文献   

2.
SUMMARY

In 1803, the most prominent Japanese astronomer of his time, Takahashi Yoshitoki, received a newly imported Dutch translation of J. J. Lalande's ‘Astronomie’. He could not read Dutch, yet he dedicated almost a year to a close examination of this massive work, taking notes and contemplating his own astronomical practices. How did he read a book he could not read? Following the clues Yoshitoki left in his notes, we discover that he found meanings not only in words, but also in what are often taken for granted or considered to be auxiliary tools for data manipulation, such as symbols, units, tables, and diagrams. His rendering of these non-verbal textual elements into a familiar format was crucial for Yoshitoki's reading, and constituted the initial step in the process of integrating Lalande's astronomy into Japanese astronomical practices, and the subsequent translation of the text into Japanese.  相似文献   

3.
In this paper we give a full account of the work of William Thomson (Lord Kelvin) on absolute temperature, which to this day provides the theoretical underpinnings for the most rigorous measurements of temperature. When Thomson fashioned his concepts of ‘absolute’ temperature, his main concern was to make the definition of temperature independent of the properties of particular thermometric substances (rather than to count temperature from an absolute zero). He tried out a succession of definitions based on the thermodynamics of ideal heat engines; most notably, in 1854 he gave the ratio of two temperatures as the ratio of quantities of heat taken in and given out at those temperatures in a Carnot cycle. But there were difficulties with using such definitions for experimental work, since it was not possible even to approximate an ideal Carnot engine in reality. More generally, it is not trivial to connect an abstract concept with concrete operations in order to make physical measurements possible. In the end, Thomson argued that an ideal gas thermometer would indicate his absolute temperature, and that the deviation of actual gas thermometers from the ideal could be estimated by means of the Joule‐Thomson effect. However, the measurement of the Joule‐Thomson effect itself required measurements of temperature, so there was a problem of circularity.  相似文献   

4.
The design of good notation is a cause that was dear to Charles Babbage’s heart throughout his career. He was convinced of the “immense power of signs” (1864, 364), both to rigorously express complex ideas and to facilitate the discovery of new ones. As a young man, he promoted the Leibnizian notation for the calculus in England, and later he developed a Mechanical Notation for designing his computational engines. In addition, he reflected on the principles that underlie the design of good mathematical notations. In this paper, we discuss these reflections, which can be found somewhat scattered in Babbage’s writings, for the first time in a systematic way. Babbage’s desiderata for mathematical notations are presented as ten guidelines pertinent to notational design and its application to both individual symbols and complex expressions. To illustrate the applicability of these guidelines in non-mathematical domains, some aspects of his Mechanical Notation are also discussed.  相似文献   

5.
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   

6.
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   

7.
In 1670, the Bolognese mathematician Pietro Mengoli published his Speculationi di musica, a highly original work attempting to found the mathematical study of music on the anatomy of the ear. His anatomy was idiosyncratic and his mathematics extraordinarily complex, and he proposed a unique double mechanism of hearing. He analysed in detail the supposed behaviour of the subtle part of the air inside the ear, and the patterns of strokes made on the eardrum by simultaneous sounds. Most strikingly, he divided the musical octave into a continuous set of regions which he colour-coded to show their effects on a listener. His work did not find its way into the mainstream of seventeenth-century mathematical studies of music, but when examined in its context it has the potential to shed light on that discipline, as well as being of considerable interest in its own right. Here, I focus on the anatomical and mathematical basis of Mengoli's work.  相似文献   

8.
9.
Historians have long sought putative connections between different areas of Newton’s scientific work, while recently scholars have argued that there were causal links between even more disparate fields of his intellectual activity. In this paper I take an opposite approach, and attempt to account for certain tensions in Newton’s ‘scientific’ work by examining his great sensitivity to the disciplinary divisions that both conditioned and facilitated his early investigations in science and mathematics. These momentous undertakings, exemplified by research that he wrote up in two separate notebooks, obey strict distinctions between approaches appropriate to both new and old ‘natural philosophy’ and those appropriate to the mixed mathematical sciences. He retained a fairly rigid demarcation between them until the early eighteenth century. At the same time as Newton presented the ‘mathematical principles’ of natural philosophy in his magnum opus of 1687, he remained equally committed to a separate and more private world or ontology that he publicly denigrated as hypothetical or conjectural. This is to say nothing of the worlds implicit in his work on mathematics and alchemy. He did not lurch from one overarching ontological commitment to the next (for example, moving tout court from radical aetherial explanations to strictly vacuist accounts) but instead simultaneously—and often radically—developed generically distinct concepts and ontologies that were appropriate to specific settings and locations (for example, private, qualitative, causal natural philosophy versus public quantitative mixed mathematics) as well as to relevant styles of argument. Accordingly I argue that the concepts used by Newton throughout his career were intimately bound up with these appropriate generic or quasi-disciplinary ‘structures’. His later efforts to bring together active principles, aethers and voids in various works were not failures that resulted from his ‘confusion’ but were bold attempts to meld together concepts or ontologies that belonged to distinct enquiries. His analysis could not be ‘coherent’ because the structures in which they appeared were fundamentally incompatible.  相似文献   

10.
Essay review     
Benjamin Franklin, the colonial American, maintained a now little-known interest in geological questions for more than sixty years. He began as a follower of English theorists, but soon assimilated some of their ideas with original speculations and discoveries, particularly regarding earthquakes. Though Franklin became famous for his experiments with electricity, he never attempted to explain earthquakes as if they were electrical phenomena; others, however, did. Through his access to American materials, Franklin contributed significantly to the work of several English and French geological theorists. Though some of his own theories were ultimately of limited value, Franklin played an important role in the international science of his time. In addition to his other accomplishments, he was colonial America's foremost student of geology.  相似文献   

11.
12.
A letter in which astronomer John Flamsteed expounded his unusual views about the causes of earthquakes survives in a number of drafts and copies. Though it was compiled in response to shocks felt in England in 1692 and Sicily in 1693, its relationship to the wide range of comparable theories current in the later seventeenth century must be considered. Flamsteed's suggestion that an ‘earthquake’ might be an explosion in the air was linked with contemporary thinking about the roles of sulphur and nitre in earthquakes underground, and in combustion, respiration, and other processes. It reveals his concern with subjects other than astronomy and the influence of his continuing contact with members of the Royal Society; it also offers an early example of how seventeenth-century work on sulphur and nitre prepared the way for ‘airquake’ and electrical theories associated with the London earthquake of 1750.  相似文献   

13.
The celebrated Swedish natural philosopher and visionary theologian Emanuel Swedenborg (1688–1772) devoted major efforts to the establishment of a reliable method for the determination of longitude at sea. He first formulated a method, based on the astronomical observation of lunar position, while in London in 1710–12. He issued various versions of the method, both in Latin and in Swedish, throughout his career. In 1766, at the age of 78, he presented his scheme for judgment by the Board of Longitude in London. The rich archive of Swedenborg's career allows an unusually detailed historical analysis of his longitude project, an analysis rather better documented than that available for the host of contemporary projectors who launched longitude schemes, submitted their proposals to the Board of Longitude, and have too often been ignored or dismissed by historians. This analysis uses the longitude work to illuminate key aspects of Swedenborg's wider enterprises, including his scheme to set up an astronomical observatory in southern Sweden to be devoted to lunar and stellar observation, his complex attitude to astronomical and magnetic cosmology, and his attempt to fit the notion of longitude into his visionary world-view. Swedenborg's programme also helps make better sense of the metropolitan and international networks of diplomatic and natural philosophical communication in which the longitude schemes were developed and judged. It emerges that his longitude method owed much to the established principles of earlier Baroque and Jesuit natural philosophy while his mature cosmology sought a rational and enlightened model of the universe.  相似文献   

14.
15.
From summer 1792 until spring 1797, Alexander von Humboldt was a mining official in the Franconian parts of Prussia. He visited mines, inspected smelting works, calculated budgets, wrote official reports, founded a mining school, performed technological experiments, and invented a miners’ lamp and respirator. At the same time he also participated in the Republic of Letters, corresponded with savants in all Europe, and was a member of the Leopoldine Carolinian Academy and the Berlin Gesellschaft Naturforschender Freunde. He collected minerals, made geognostic observations, performed chemical and physiological experiments, read the newest scientific journals, and prepared and published texts on mineralogy, geognosy, chemistry, botany and physiology. Humboldt did his scientific investigations alongside his administrative and technical work. This raises the question of whether there were fruitful interactions between Humboldt's technical-administrative work and (parts of) his natural inquiry. I argue that the mining official Humboldt was a late eighteenth-century figure of hybrid savant-technician. Mines and smelting works provided numerous opportunities for studies of nature. Humboldt systematically used inspection tours for mineralogical and geognostic observations. He transformed mines into chemical laboratories, and he transferred knowledge and material items from his natural inquiries in mines to academic institutions. The main objective of this paper is to illuminate the persona of savant-technician (or scientific-technological expert) along with Humboldt's mixed technological and scientific work during his term as mining official.  相似文献   

16.
17.
Descartes developed an elaborate theory of animal physiology that he used to explain functionally organized, situationally adapted behavior in both human and nonhuman animals. Although he restricted true mentality to the human soul, I argue that he developed a purely mechanistic (or material) ‘psychology’ of sensory, motor, and low-level cognitive functions. In effect, he sought to mechanize the offices of the Aristotelian sensitive soul. He described the basic mechanisms in the Treatise on man, which he summarized in the Discourse. However, the Passions of the soul contains his most ambitious claims for purely material brain processes. These claims arise in abstract discussions of the functions of the passions and in illustrations of those functions. Accordingly, after providing an intellectual context for Descartes’s theory of the passions, especially by comparison with that of Thomas Aquinas, I examine its ‘machine psychology’, including the role of habituation and association. I contend that Descartes put forth what may reasonably be called a ‘psychology’ of the unensouled animal body and, correspondingly, of the human body when the soul does not intervene. He thus conceptually distinguished a mechanistically explicable sensory and motor psychology, common to nonhuman and human animals, from true mentality involving higher cognition and volition and requiring (in his view) an immaterial mind.  相似文献   

18.
The life of Ludwig Boltzmann (20 February 1844–5 September 1906) and his influence on science is reviewed. This great Austrian scientist was not only the founder of statistical mechanics and a gifted experimentalist, but his pioneering ideas influenced all the physical sciences. In his honour, many Austrian research institutes carry his name. He had great influence on Albert Einstein whose first papers were, according to his own words, in the spirit of Boltzmann, and intended to proved the reality and the size of certain atoms using the molecular fluctuations postulated by Boltzmann. Max Planck was converted from a ‘Saulus’ to a ‘Paulus’ when he had to use Boltzmann's method to derive his famous law of radiation. In fact, Boltzmann had already used discrete energy levels as early as 1872. Yet his work was heavily criticized by the neopositivists around Ernst Mach and seemed to receive very little attention in the last years of his life when a great number of physicists did not believe in atoms. It is the tragedy of Boltzmann's life that he did not experience the glorius victory of his ideas, but died under the gloomy vision that the work of his whole life was doomed to oblivion.  相似文献   

19.
Relativism is one of the most problematic terms associated with philosophical discourse, with Feyerabend considered among the most important twentieth century theorists subscribing to it. This paper provides a detailed overview of relativist positions advanced in Feyerabend's mid-to-late work and investigates the associated epistemic and political applications. Emphasis is placed on how Feyerabend supported certain aspects of relativism, and at what stage he rejected others. It is noted that Feyerabend had already imposed limitations on relativism in Farewell to Reason, in which he entertained the possibility of epistemic definition within stable contexts, and advanced the notion that opportunities and equality associated with political and cultural units could only be valid within a democratic system. In Conquest of Abundance, political relativism is largely discarded, while epistemological relativism is increasingly treated as an appeal for diversity in all areas.In this re-reading of his work, it becomes clear that Feyerabend was already advocating a moderate form of epistemic and political relativism in the middle of his career, which he subsequently developed in the direction of “ontological pluralism” in his later work. This paper thus shows that Feyerabend's relativism should not be completely rejected, but rather that it continues to offer interesting food for thought.  相似文献   

20.
John Harrison (1693–1776) is regarded as the father of chronometry. During his lifetime, he relentlessly pursued one of humankind's greatest and oldest challenges—that of finding the longitude at sea. In succeeding (according to the rules dictated by an Act of Parliament), he bequeathed to humankind the most accurate portable timekeeper the world had ever seen. It is a remarkable fact that his timekeeper, known today as H4, remains more accurate than the majority of expensive mechanical wristwatches manufactured today. Such accuracy required novel approaches to address the various difficulties that befall all mechanical watches, and Harrison overcame many of these with his own innovations. The reduction or elimination of friction is one such problem with clocks and watches, and from an early age Harrison demonstrated his mastery in this subject. This is typified by his choice of woods in his early clocks, and in later clocks by his ‘grasshopper’ escapement. In the 1750s, Harrison's attention switched from clocks to watches, necessitating a hardwearing, low friction material to be found for the pallets in the escapement of his timekeepers. He found these properties in diamond, and in utilizing this to great effect in H4's escapement, he became one of the first people to use diamond as a high-tech material. This paper describes a scientific investigation into the diamond pallets of H4 using Raman microscopy, X-ray diffraction and optical microscopy, to elucidate why diamond was used rather than a more conventional jewel such as ruby, and to gain some insight into how Harrison might have achieved their unconventional morphology. From the evidence presented here, together with evidence collected from primary sources, it is shown that his use of diamond as a hard, low friction material was nothing other than extraordinary, and should be regarded in the same high esteem as his other technological gifts to the world.  相似文献   

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