The Fabulous Tales of the Common People,Part 1: Representing Hadrian’s Wall

Abstract

Hadrian’s Wall is one of the most instantly recognizable ancient monuments in the UK. This paper explores the historical and contemporary visualization practices which have created this iconic image. Moving between the disciplines of archaeology, cultural geography, and heritage and tourism studies, the paper draws upon a variety of data sources such as paintings, photographs, models, and reconstructions to consider how the Wall is visually represented within contemporary public discourse. The paper focuses on digital photography and considers the ways in which images create and sustain particular readings of the Wall’s function and significance. These contemporary representational practices demonstrate strong continuities, and earlier images are used to provide historical context. Emphasis is placed on the monument’s landscape setting in visual representations and the importance of this environmental context for readings of the Wall’s cultural and political significance. The present paper deals primarily with representations of the Wall, but it is argued that these representational practices are also fundamentally embodied. The physical encounters of visitors and archaeologists will be considered in greater detail in the second part of this study (Witcher, forthcoming).     

Snapshots: Images of Men in the United States Colored Troops

Abstract

This article considers the intertwined impact of two very different developments that emerged during the era of the American Civil War. The first concerned the invention and dissemination of new photographic technology that made it possible for ordinary citizens to sit for portraits and come away with multiple copies of new cartes de visite. The second concerned the revolutionary decision by the federal government to recruit African American men into the Union Army. As a result, in the final two years of the war uniformed African American men were having their portraits taken, and those small images began circulating among friends and family members. This speculative essay considers how these small cultural artifacts might have reflected and shaped a world in transition.     

Lead pigments and related tools at Akrotiri,Thera, Greece. Provenance and application techniques

This paper refers to an investigation of finds that are associated with the raw materials and tools for the preparation or use of lead pigments at Akrotiri on Thera, Greece, during the Early, Middle and Late Cycladic Bronze Age (c. 3000–1600 BC). For the detection and the preliminary characterisation of remains of pigments that were found on stone tools, the in situ application of X-Ray Fluorescence spectroscopy proved to be invaluable. In order to identify the chemical composition of the pigments and to investigate their provenance from a geological perspective, quantitative X-Ray Diffraction analysis was conducted. A thorough visual macro and microscopic examination of the morphology of the materials permitted the determination of physical features (colour, homogeneity, grain size) as indicators of their nature or degree of processing. Based on the results of these analyses, the traces of lead oxides that were detected on the stone tools are associated with specific collections of litharge items discovered at the settlement of Akrotiri, and probably provide evidence of their earliest use in preparing pigments.     

Characterization of elemental and firing-dependent properties of Phlegrean ceramics by non-destructive ED-XRF and NMR techniques

A combination of energy dispersive X-ray fluorescence (ED-XRF) and 2D proton nuclear magnetic resonance (¹H NMR) relaxometry was employed for the characterization of two groups of similar ceramic fragments from the high-medieval production of the Phlegrean area (Miseno and Cuma, Southern Italy). Both methods are based on the use of non-destructive and portable instruments. This approach allows to correlate complementary microstructural features of ceramics, both dependent and independent of the firing technique.     

文物保护科技研究中的X射线照相技术

阐述了X射线机的工作原理,并列举软、硬X射线机在青铜、陶瓷、书画、漆木器等文物检测分析中的应用实例,揭示了X射线照相技术在获取文物内部信息,反映各类文物的保存状况、制作工艺、修复情况、病害现象、内部缺陷、真伪鉴别等方面的积极作用。同时,介绍了X射线照相技术应用在文物检测中的经验,并对X射线照相技术在文物无损检测中应用前景作了展望。     

Evidence for volcanic ash fall in the Maya Lowlands from a reservoir at Tikal,Guatemala

Powder X-ray diffraction and petrographic analyses of reservoir sediments from Tikal, Guatemala have identified significant quantities of decomposed volcanic ash in the form of smectite and euhedral bipyramidal quartz crystals. X-ray fluorescence trace element content analysis was used to eliminate distant Sahara-Sahel and Antilles sources. The Zr/Y and Ni/Cr ratios of reservoir sediment from Tikal are consistent with a source from Central American volcanism (e.g., Guatemalan and Salvadoran). AMS radiocarbon dating of the smectite and crystalline quartz-rich reservoir sediments show that volcanic ash fell during the Preclassic, Classic, and Postclassic Maya cultural periods. It may now be possible to develop an effective chronology of ash fall at Tikal and the greater Peten.     

Natural preservation mechanisms at play in a Bronze Age wooden shovel found in the copper mines of Alderley Edge

A wooden shovel, dating from the Early Bronze Age, has survived in a remarkable state of preservation in the copper mines of Alderley Edge, Cheshire UK. Other historic timbers recovered from the mines, whilst still intact, have fared less well. An X-ray investigation into the distribution of minerals through the shovel using portable X-ray Fluorescence (PXRF) along with the use of synchrotron-based X-ray Absorption Spectroscopy (XAS) measurements of the copper and arsenic chemical speciations has provided clues to the methods by which metals from the mining environment have entered the wood of the shovel and ensured its survival. The distribution and nature of the minerals so determined suggest that the copper and arsenic, along with a significant lead content, entered the shovel during its original use in working mineral-rich deposits, rather than through the burial environment. The insights gained are expected to be applicable to other wooden artefacts recovered from ancient copper mines in other places.     

南唐二陵壁画历史保护修复材料的分析

为了确定南唐二陵壁画已有保护修复材料的种类,使用多光谱摄影技术分别对钦陵和顺陵壁画保护修复材料的分布区域进行探查,在紫外荧光图像中确定了保护修复材料的位置,通过红外光谱和热裂解-气质联用技术对材料进行了成分分析。结果表明二陵壁画所使用的保护修复材料主要为苯乙烯-甲基丙烯酸甲酯共聚物和聚醋酸乙烯酯,还发现少量多糖类物质,为调和地仗石灰层所使用的糯米汁。该研究表明通过多光谱摄影技术提供线索,使用红外光谱、热裂解-气质联用确定成分是一种可靠的墓葬壁画保护修复材料分析方法体系,为墓葬壁画保护修复材料的鉴别提供借鉴,也为保护修复材料在墓葬壁画中的应用效果评价和劣化机理研究提供参考。     

Tools for Predicting Damage to Archaeological Sites Caused by One-Dimensional Loading

Tools are developed to predict damage to archaeological remains caused by the construction of line infrastructure on soft soil. They are based on numerical modelling and laboratory testing supported by X-ray microcomputed tomographic observations, and micromorphological analyses of thin sections. They have been validated for one-dimensional (1D) loading at two sites in the Netherlands where soil has been placed on top of organic layers rich in ecofacts and overlaying Pleistocene sands.

Numerical prediction of the deformation of soft layers underneath an embankment remains a challenge for geo-technical engineers. Errors on surface settlement prediction reach ±15% of the measured total settlement.

Laboratory observations show that vulnerable artefacts can get crushed when packed loosely in pure assemblies under 1D loading equivalent to less than 5 m of sand. Fragmentation is assimilated to loss of archaeological value as it compromises recovery during sieving. Embedment in a sandy or a very compressible organic matrix has a beneficial effect on the resistance of ecofacts. Embedded ecofacts can resist a load of more than 12 m of sand. Flattening and re-orientation of soft plant remains occur during 1D loading without microscopic damage of tissues.