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An analysis of the scale used by the designer of the Plan of St Gall allows for no other conclusion than that the mill and mortars shown on this Plan were water driven. Because of the paradigmatic nature of the Plan this means that hydraulically operated mills and mortars were by the makers of the Plan considered to be standard equipment of a Carolingian monastery — a conclusion supported by a wealth of other documentary source material available for this period.The Romans knew the water mill, but made little use of it. Its general adoption and diffusion in Merovingian and Carolingian Europe is in this study attributed to the rise and spread of Benedictine monasticism. It received its primary impetus from the need to provide milled and crushed grain in bulk for communities of considerable size, including a leisure class of men who had to be freed from the normal chores of toiling for life so that their energies could be directed to their primary task: the Work of God (Opus Dei). Water-powered trip hammers were in use in China before the birth of Christ. Their portrayal on the Plan of St Gall suggests that they were introduced in western Europe, not by Marco Polo, as some propose, but in the age of folk migrations or the early Carolingian Period.  相似文献   
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This article is an exploration of concept of monks as “soldiers of Christ” in Byzantine Anatolia during the late sixth and early seventh centuries CE. Through a case study of Theodore of Sykeon, this article will explore monks as agents of continuity in the Byzantine Anatolia of the late sixth and early seventh centuries through Theodore's conflicts with the emperors, imperial authorities, and the regional episcopal hierarchy. The conflicts Theodore had with various authority figures of his time were about helping them see the right path of supporting Catholic orthodoxy as the normative belief system of Byzantine society and integrating his rural community of Sykeon into the wider web of imperial and episcopal urban patronage. Thus, conflict in this context was a catalyst for social order and stability rather than a symptom of social collapse. This article also fits into the historiography of the holy man as local patron in Late Antiquity, suggesting an alternate interpretation of this phenomenon as first put forward in Peter Brown's seminal works on this subject.  相似文献   
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Frankish kings exacted unpaid military service from their subjects in both Merovingian and Carolingian times. The basis for this right has long been uncertain. A study of the term ‘manse’ as a Carolingian measure of assets brings to light the ostensibly hidden property on whose basis Franks went to war. This military duty reached back to the origins of the Frankish kingdom, when a large share of Roman taxes was awarded in individual allotments to soldiers obligated to serve, otherwise unpaid, when summoned, and heavily fined if they did not. Both demesne and tributary manses – contributory units – were the main part of state resources applied to military costs. They cannot be simply envisaged as components of an agricultural scheme (grand domaine). A tax‐like military obligation was one among several institutions actively surviving from the fifth century to the ninth, and it suggests that Frankish government was more law‐based and administrative than is often allowed.  相似文献   
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The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ13C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ13C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ13C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of 13C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ18O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ13C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ13C values between +15 and +34‰ PDB. Radiocarbon and 230Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.  相似文献   
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