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The deposition of Early Neolithic material within tree-throw hollows in described, and the possible role of fallen trunks as places of occupation, settlement foci and landscape markers is discussed. Having implications for the interpretation of ubiquitous later Mesolithic pit dwellings, the evidence suggests a continuity of forest 'identity'. Accordingly, patterns of clearances are also explored in relationship to modes of occupation, and the employment of 'big wood' in Neolithic monuments discussed.  相似文献   
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This article discusses the development of the Livens Large Gallery Flame Projector, a massive British flamethrower that was used against German trenches in the Battle of the Somme in 1916. Built underground within tunnels below No Man’s Land, this secret weapon was an attempt to use technology to break through German defences and reduce British casualties. The flame projector was the most effective flamethrower developed in WWI, but proved to be too inflexible and expensive to be widely used.  相似文献   
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Survey of the coastal and inter-tidal zone at Kilwa in Tanzania resulted in the discovery of a series of artificial causeways and platforms at the entrance to the harbour of Kilwa Kisiwani, an important port trading with East Africa and southern Asia from around the 13th century. These appear to be part of a phase of monumental stone building at Kilwa in the 13th to 16th centuries, and represent a prosperous, confident Kilwa, impressing foreigners arriving by sea. Although necessarily speculative, several possible interpretations of their functions are advanced including navigation, protective breakwaters, access to marine resources, or ceremonial use.
© 2007 The Author  相似文献   
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The quantitative analysis of glass, ceramics and related silicate systems by means of energy dispersive X-ray fluorescence spectrometry is considered and problems arising from the selective absorption of X-rays in multi-element specimens are discussed. A computer programme written in FORTRAN and based upon a “semi-fundamental parameters” approach to the correction of matrix effects in glass and chemically similar materials is fully described. Model data are provided to enable the programme to be run and tested. An “empirical coefficients” computer programme for the quantitative analysis of silicate systems is outlined and the limitations of this type of programme are pointed out. The importance of adequate sample preparation prior to X-ray spectrometric analysis is stressed.  相似文献   
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