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1.
ABSTRACT

This paper investigates the firing of seventeenth Century musket balls. Prior to this research, the main concerns with making range predictions were associated with the deformed shape of the musket balls affecting their drag coefficient and therefore their distance to ground impact. However, the distance due to bounce and roll after initial impact has been unknown. In this work, the distance travelled after the first ground impact greatly exceeded expectations, with the musket balls approximately doubling the distance to their final resting positions. From these findings the initial factors thought to have had high relevance to the final resting position of the musket ball (velocity variation and drag co-efficient) become less significant and factors such as ground hardness become more prominent. The knowledge gained during this investigation will allow more accurate information to be obtained on the firing positions of opposing forces during conflicts in the English Civil War.  相似文献   

2.
The assessment of the firing temperature of a prehistoric pottery sample collected from ancient Mesopotamia, Turkey was studied using luminescence techniques. The methods for this estimation involved the observation of the thermal and pre‐dose sensitization with various re‐firing temperatures for both TL and the OSL signals. In the former case, the 110°C TL peak and the rest of the glow curve were used as proxies in this study. In the framework of a first attempt to investigate the impact of grain‐size dependence on the sensitization of the luminescence signals, the aforementioned study was performed with four different pottery grain‐size fractions: (i) less than 60 μm, (ii) 60–90 μm, (iii) 90–180 μm and (iv) 180–250 μm. The results clearly demonstrated the firing temperature mark of ~500°C in for the grain size of 90–180 μm, while—as in the case of the lower grain‐size fraction—a third proxy, the ratio of the pre‐dosed to the thermal sensitization, was seen to indicate the firing temperature. The remaining two grain‐size fractions failed to provide any meaningful results with regard to the firing temperature estimation. The dependence of the TL characteristics on the grain size was explained in the framework of the mixed mineralogy.  相似文献   

3.
The pioneers of modern agricultural settlement in the Holy Land were Christians. Foremost among these were several Americans who came in the 1850s and 1860s to settle—ignoring warnings from local experts and from representatives of the United States government. The leaders of the settlers were inspired by millenarist ideas and by faith in the Return to Zion—rife among fundamental Protestant sects in the early nineteenth century. The personal accounts of these visionaries provide insights into what drove them to attempt to migrate to remote and backward Palestine and also throw light on the economic concepts and practical plans for implementing their schemes. Despite their failure, these attempts were very important in the history of agricultural settlement in nineteenth-century Palestine. The settlers maintained a wide range of international contacts through letters, pamphlets, sermons and publicity in the press in America, England, Germany and Palestine. In addition, many people who heard indirectly about these ventures, took an interest in their ideology and practice. Millenarist schemes influenced early preachers and founders of Jewish societies for agricultural settlement in Palestine. The Jewish forerunners of the Hovevi Zion and Zionist movements promoted remarkably similar ideas. Millenarist and Jewish visionaries alike spoke of the hour being propitious for the coming of the Messiah and favourable for settlement in the land of Israel. Both groups established schools to teach the lore of the land and to educate youth in agricultural pursuits. Many years after the disappearance of American settlers from Palestine, their story reverberated in Jewish polemic literature.  相似文献   

4.
Tom Mels 《对极》2014,46(4):1113-1133
In Henri Lefebvre's work, abstract space entails qualitatively new ways of envisioning and strategically arranging the sites within which capital accumulation and everyday life are to unfold. This paper sets out to delineate how this premise can be profitably used to decipher contested tactics of primitive accumulation. Arguing from a particular case—nineteenth‐century reclamation of mires on the island of Gotland, Sweden—the paper explores how primitive accumulation was made possible through the conjunction of three spatialities, representing three key lines of struggle over abstract space. The abstraction and avowed homogeneity of space was produced and regulated by concurrent ideological maneuvers against customary practice, leveled by scientific discourse, and pursued through a legally endorsed material transformation of nature.  相似文献   

5.
6.
N. Wood  He Li 《Archaeometry》2015,57(4):617-635
Through a combination of analysis and synthesis of Laohudong Guan ware shards from Hangzhou City in southern China, some new hypotheses concerning Guan ware manufacture can be proposed. These suggest that the complex microstructures seen in Guan ware glazes, and which contribute significantly to their jade‐like qualities, may owe much to layers of fine bubbles trapped during the glazing process. It is also proposed that the multi‐layer glazing methods used at the Guan ware kilns at Hangzhou may have helped initially to disguise the relatively coarse and ferruginous clays used for Guan ware manufacture. Once established, the layered glazing technique was used for its own sake—eventually yielding wares that could comprise more glaze than clay. Raw materials and firing temperatures were also explored for this study, and these suggest the use of porcelain‐stone/wood ash mixtures for glaze‐making, with 20–30% calcareous wood ash being the usual amounts. The average heat‐work for the glaze firing seems to have been equivalent to Orton Cone 7, giving a typical finishing temperature of ~1215°C. A single biscuit firing and a single glaze firing seem likely for most Laohudong Guan wares. Studies of the losses that occur in the preparation of calcareous wood ashes suggest that very large quantities of botanic material must have been burned to provide ash for glaze‐making at the Laohudong kiln. From the environmental perspective, a combination of thick glazes and heavy wood‐ash usage would have placed great demands on local fuel supplies.  相似文献   

7.
In this paper, I reconsider the problem of pottery firing using a large set of comparable data, most of it collected during extensive fieldwork conducted in Africa and Asia. My main purpose is to assess the actual relationships between the firing procedures (structure, fuel, schedule and scale) and some of the firing conditions (time and temperature). Indeed, if different firing procedures result in different firing conditions, the fired pots might display distinct physical characteristics. I will first characterize the various procedures in terms that are both meaningful for anthropologists and likely to influence the thermal profile of a firing. I will then examine the characteristics of the various firing processes in terms of duration, maximum temperature, heating rate and soaking time.  相似文献   

8.
This paper argues that Machiavelli's method, his inductive and comparative use of history and experience for political analysis, and his fashioning of historical-political analysis as ‘science’, played an important and still unrecognised role in his reception in the sixteenth century. It makes the case that Machiavelli's inductive reasoning and stress on historia and experientia offered a model for scientific method that open-minded sixteenth-century scholars, eager to understand, organise and augment human knowledge (scientia), could fit to their own epistemology. By focusing on the question of method—a crucial issue for sixteenth-century contemporaries—the paper offers more than a key to the understanding of Machiavelli's positive reception. It also helps in apprehending the crucial importance of Lucretius to Machiavelli's scholarship; the role of the late Renaissance fascination with historia in his reception; and the breadth of appropriation of his method exactly in the decades when anti-Machiavellianism became official politics all over Europe. These claims are sustained through the cases of Machiavelli's early translators and promulgators; the French legal humanists and historiographers; the Swiss, Italian and French scholars engaging with medicine, Paracelsism and astronomy; the authors of political maxims from all over Europe; and finally Francis Bacon.  相似文献   

9.
I. Sondi  D. Slovenec 《Archaeometry》2003,45(2):251-262
The mineralogical characteristics of four Lamboglia 2 Roman‐age amphorae excavated from ancient underwater shipwreck localities in the central Adriatic were investigated. X‐ray diffraction and optical microscopy analyses showed that the amphorae have similar primary mineral compositions, mainly consisting of quartz, plagioclase, potassium feldspar, diopside, illite and calcite, most probably originating from clayey Eocene flysch deposits used as raw materials in manufacture. The difference in mineral composition between these samples is recognized from the presence or absence of melilite, high‐magnesium calcite, aragonite, gypsum and analcime. It was shown that melilite is a secondary mineral formed during the firing process, while the others, which build up through incrustation of marine benthonic communities on the amphora walls and fill the cracks in the amphora bodies, were formed by crystallization in seawater. The firing of the original pieces of amphorae showed that melilite could be formed at temperatures higher than 800°C, most probably through interaction between calcite and silicate minerals present in the raw materials. The presence of melilite, and the absence of illite and calcite, were used to estimate the firing temperature of the amphorae during their production.  相似文献   

10.
ABSTRACT. This article highlights two processes that shaped Swiss nationhood in the long nineteenth century. The first concerns the competition between different nation‐states and the nationalist visions these contests engendered. In a Europe dominated by the norm of the culturally and ethnically homogenous nation, the Swiss authorities, public intellectuals and various political representatives were desperate to display an image of national authenticity to the outside world. The result was a nationalism that combined voluntaristic and organic elements. In the second and main part of this article, the focus turns on citizenship; it is conceived not only as a social and legal institution, but also as a cognitive prism through which people defined their membership in the national community. Remarkably, the authority in granting national citizenship to foreign nationals remained firmly in the hands of the cantons and, above all, the Swiss municipalities. In practical terms, this meant that the Gemeinde provided the institutional and cognitive frame through which nationhood was primarily experienced, imagined and defined. While Switzerland represents a particularly strong case of a communalist polity, it should not be treated as unique. Instead, it should alert us to a potentially fertile yet little‐explored area of research: what might be called the communal embededdness of the national(ist) imagination.  相似文献   

11.
This article examines how Maoist theory and practice were imported to France during the 1960s. A syncretic phenomenon, as notions developed in the Chinese cultural context were adapted to the very different Gallic situation, French Maoism proved to be especially influential among students at the École normale supérieure at the rue d’Ulm in Paris, where the Marxist theoretician, Louis Althusser, was teaching. Maoist philosophy facilitated critiques of the Moscow-aligned French Communist Party and its student union; it enabled Althusser's rethinking of the Marxist tradition, and it ultimately provided ammunition for his students’ eventual break with his “theoreticism.” Maoism's fecund contribution to French intellectual culture in the 1960s, helping to lay the groundwork for the events of May 1968, derived principally from its dual theoretical and practical nature. This article highlights two specific Maoist tenants—the inevitably violent nature of revolution and the ersatz-empiricist method of the “investigation”—and suggests how, after 1968, French Maoism ultimately surrendered the former as the latter proved more useful to direct democratic politics.  相似文献   

12.
Based on a chronicle written and translated by the Otomi — an indian group living in Querétaro City to the east of the Mexican Bajio, this work intends to describe the way they conceived the Spanish Conquest in the mid‐XVIIth century. By recalling, interpreting and idealizing their past these indians elaborated a version that conveys a complex and hopeless search for autonomy and identity in a context of social decay and crisis. This text is also a rare manifestation of colonial indian literature. Its analysis discovers the way Indians could use writing, oral and written sources to create and express an original way of coping with the past, time and colonial society.  相似文献   

13.
The study intends to support the archaeological questions about the technological choices related to the manufacturing of an important class of archaic artefacts—the fictile roof revetments of the temples—in the Greek colonies of Sicily, unveiling the possible relations among raw materials, decorative and firing techniques and functionality of the architectural terracottas. By applying a multidisciplinary and a multimethodological archaeometric approach, the aforementioned questions have been addressed, explaining the technological expedients employed by the coroplasts in the manufacturing of the roof revetments, and suggesting interesting mobility schemes of both raw materials and ‘techne’ (know‐how) throughout the island.  相似文献   

14.
The space of exception has been extensively discussed as a location in which governing technologies are deployed through the suspension and manipulation of the norm. The scholarship on the subject has underscored the ways in which various localities can be encamped, which alludes to the dynamic in which spaces of exception can be shaped through the application of various means of sovereign violence that produces new and unpredictable norms. Building on this literature, the article analyzes the ways in which the exception is intentionally used in order to spatially construct the norm. Two case studies are discussed: Israel's occupation of the Golan Heights and the Turkish occupation of Northern Cyprus. The article's main aim is to show how the state of emergency, which provided the justification for deploying exceptional means—occupation and subsequent colonization—was domesticated. By domestication I mean a situation whereby the state of emergency is not fully negated, but rather rearticulated and redeployed in order to reshape the space and transform it so that it is concomitantly both threatening and normal. I go on to show, however, how despite the processes of spatial normalization the state of exception always resurfaces.  相似文献   

15.
Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures.  相似文献   

16.
In the preface to his liturgical calendar The reckoning of the course of the stars Bishop Gregory of Tours (538–594) — author also of Ten books of histories and Eight books of miracles as well as of a Commentary on the understanding of the Psalter (of which, however, only fragments are preserved) — declares God's “wonders” of the natural world to be superior to the seven ancient wonders of the world. The reason for this is that the latter, being works of men, are subject to decay and destruction, while the former, as miraculous works of God, are divinely sustained and renewed daily or annually, thereby becoming imperishable. An examination of the associative contexts in which two of these wonders — the sea (enlarged to include water in its various forms) and plant life — occur in the rest of Gregory's works reveals several essential themes of his thinking not only about nature, but also about God, man and society. Thought, for him, nature as a (divinely sustained) system of regularities does exist as a kind of backdrop, sudden unpredictable divine — and sometimes diabolic — action in and through phenomena occupies the center of the stage. Gregory tends to see this action in the shape of what he regards as pre-existing images or patterns of invisible spiritual truth, to which the visible, even material, structure of events must necessarily conform. He shows, too, how this action could reflect as well as meet various needs of the individual and of society as a whole. An association which recurs almost constantly in his treatment of divine action in these natural phenomena, which he sometimes describes as analogous to that in man, is precisely that with the cluster of closely related concepts of renewal, rebirth and creation ex nihilo. Together with what appears as an extreme, as it were ‘poetical’, sensitivity to sudden perceptions and intuitions, something like a longing for and surrender to what he describes as “astonished admiration” may have helped to make possible his recognition of that which he designated as divine creative power in the world of visible reality as well as in man's inner experience. His seeing this as an essential dynamic of the holy may mean that he felt it to be a fundamental need and concern not only of the individual personality but also, more obscurely, of the society in which he found himself.  相似文献   

17.
Among the nations that comprised the British Empire, the First World War has generally either been forgotten, as in India, as irrelevant to the achievement of political independence, or remembered, as in Canada, as the catalyst for developing a separate national identity. This article argues that both these historical interpretations ignore the extent to which the First World War was a shared British Empire experience. The article examines the establishment of the War Munitions Supply Company of Western Australia as an example of the popular movement to make artillery ammunition that swept many parts of the British Empire in 1915. The munitions movement provided an outlet for the patriotic surge that occurred in April–May 1915 in reaction to the German use of poison gas and the sinking of the Lusitania. It was also an attempt to overcome wartime economic disruption by creating a new local industry. The practicalities of cost and shipping meant that by 1917 artillery ammunition production was continued only in Britain, Ireland, and Canada, but in 1915 the Western Australian company was part of an Empire-wide movement to make munitions and support the war.  相似文献   

18.
In the preface to his liturgical calendar The reckoning of the course of the stars Bishop Gregory of Tours (538–594) — author also of Ten books of histories and Eight books of miracles as well as of a Commentary on the understanding of the Psalter (of which, however, only fragments are preserved) — declares God's “wonders” of the natural world to be superior to the seven ancient wonders of the world. The reason for this is that the latter, being works of men, are subject to decay and destruction, while the former, as miraculous works of God, are divinely sustained and renewed daily or annually, thereby becoming imperishable. An examination of the associative contexts in which two of these wonders — the sea (enlarged to include water in its various forms) and plant life — occur in the rest of Gregory's works reveals several essential themes of his thinking not only about nature, but also about God, man and society. Thought, for him, nature as a (divinely sustained) system of regularities does exist as a kind of backdrop, sudden unpredictable divine — and sometimes diabolic — action in and through phenomena occupies the center of the stage. Gregory tends to see this action in the shape of what he regards as pre-existing images or patterns of invisible spiritual truth, to which the visible, even material, structure of events must necessarily conform. He shows, too, how this action could reflect as well as meet various needs of the individual and of society as a whole. An association which recurs almost constantly in his treatment of divine action in these natural phenomena, which he sometimes describes as analogous to that in man, is precisely that with the cluster of closely related concepts of renewal, rebirth and creation ex nihilo. Together with what appears as an extreme, as it were ‘poetical’, sensitivity to sudden perceptions and intuitions, something like a longing for and surrender to what he describes as “astonished admiration” may have helped to make possible his recognition of that which he designated as divine creative power in the world of visible reality as well as in man's inner experience. His seeing this as an essential dynamic of the holy may mean that he felt it to be a fundamental need and concern not only of the individual personality but also, more obscurely, of the society in which he found himself.  相似文献   

19.
57Fe Mössbauer spectroscopy provided relevant information on the firing techniques employed in manufacturing concotto and coarse pottery, two types of fired clay mixtures (impasti) of the protohistoric settlement site of Concordia Sagittaria. The firing techniques of Concordia were reconstructed by comparing the Mössbauer patterns of the artefacts with those of the local raw clays fired in the laboratory. The concotto was produced in kilns by firing clay mixtures under oxidizing conditions at 700–1000°C, or at lower temperatures in the open air. The firing of these clay mixtures containing mainly ground pieces of waste pottery, resulted in hard and variously coloured construction materials, particularly suitable for humid environments. In turn, the coarse pottery was produced by firing clay mixtures more homogeneous than those used for the artefacts of concotto. The firing of coarse pottery was performed under reducing conditions at about 900°C with a final exposure to air by opening the hot kiln. Light and agreeable coarse pottery, with a red surface on the grey-black core, was obtained when the effective temperature of air was higher than 500°C.  相似文献   

20.
The spatial dimension of competition among retail outlets is well researched and typically captured with spatial interaction models. A stream of theoretical research has studied the consequences of incorporating various types of dynamics into these models. We build on this research by incorporating a behavioral decision process based on bounded rationality, and by allowing for unexpected adversity in the environment in the form of exogenous shocks. Given these characteristics—spatial competition, boundedly rational decision making, and environmental adversity—we study the long-run dynamics of a model retail industry. The model reaches a stochastic steady state which is “poised,” in the sense that a shock may—or may not—trigger a wave of innovation which sweeps the entire system. Detailed investigation of this steady state shows that it has the characteristics of a general type of organization, known as self-organized criti-cality, that has been described in both theoretical biology and statistical physics.  相似文献   

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