Restrictions on fluorine depth profiling for exposure age dating in archaeological bones

Archaeological fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil. The fluorine ion replaces the hydroxyl group in the mineral phase of the bone, forming chemically more stable fluorapatite. In cortical parts of the long bone diaphysis a fluorine concentration profile can be observed, which decreases from the outer surface and the marrow cavity towards the inner parts of the bone matrix. Geological time spans are needed for this process to reach equilibrium and for the distribution to become uniform. As the shape of the profile, which can be described by a diffusion model, contains information on the exposure duration of the fossil object, several attempts to use fluorine profiling as a dating method have been undertaken. The distribution of fluorine in an archaeological sample however is strongly influenced by environmentally induced processes of bone diagenesis, i.e. alteration in the structure and composition of the mineral phase and degradation of organic components that may make the time information indistinct. The primary chemical composition of bones can thus be obscured by diagenesis within tens, hundreds or thousands of years. This depends more on the diagenetic environment than on the geological age. To observe the impact of environmental influence on the profile shape, samples from several burial sites featuring various soil conditions have been analyzed for their fluorine distribution and preservation state. This paper provides an overview on the restrictions that have to be considered when attempts are undertaken to relate a fluorine diffusion pattern to the archaeological age of a bone specimen.     

War Shields of the Torricelli Mountains,West Sepik Province,Papua New Guinea

ABSTRACT The usefulness of the term ‘ethnolinguistic group’, as a construct suggesting that ‘differences in language automatically translate into differences in culture’, has been questioned by Welsch, Terrel and Nadolski (1992). Not many researchers would insist on the term ‘automatically’, but would nevertheless support an argument for a strong correlation between material culture and language. As a contribution to this debate, we discuss two types of wood shields of the Torricelli Mountains (one of which is being identified for the first time) and pigskin shields to the south of the Torricellis, their use, and the details of the carved designs of the wood shields. The results of our analysis provide limited support for the correlation of material culture and language but highlight the need for analysis of material culture based on reliable data for a large number and wide range of artefacts, from defined regions, presently held in museums and private collections worldwide.     

Elevated lead exposure in Roman occupants of Londinium: New evidence from the archaeological record

The evolution of metallurgical practices over several millennia has resulted in human exposures to a diverse variety of toxic elements. These exposures were not just confined to the metalworkers, but in many cases broadly impacted the larger community and society. The role of lead in Roman civilization is particularly fascinating, where the available evidence of lead use in a myriad of applications by Roman civilization suggests the potential for elevated exposures. The present paper addresses the hypothesis that because of these practices, Roman occupants of ancient Londinium (43–410 ad ) were exposed to levels of lead that far exceeded exposures in the preceding populations of Iron Age Britain (700 bc –43 ad ). The elemental content and stable lead and strontium isotopic signatures of 30 femora from three Londinium cemeteries and radiocarbon-dated representative burials were examined and the results then compared with 70 femora dating to the pre-Roman Iron Age from the well-known Iron Age hillfort of Danebury, Hampshire, and from three cemeteries in East Yorkshire. Extensive efforts were directed at the minimization of sediment and soil contamination, the assessment of contamination from burial artefacts and a careful review of the burial context of specimens. Data for lead and 20 additional trace and major elements were obtained by magnetic sector inductively coupled plasma mass spectrometry (ICPMS), after acid dissolution of pre-cleaned bone cores. Lead isotope ratios in the bone core digests (and burial soils) were measured by multi-collector ICPMS. It was found that concentrations of lead in the Roman/Londinium-era femora were > 70-fold greater than those from pre-Roman populations. This was confirmed by femoral data obtained from the analysis of a pre-Roman burial from the early first century bc found adjacent to the Southern Cemetery. Several major and trace element metrics for diagenesis demonstrate that levels of lead in the bone are robust indicators of human exposure during life. Lead isotope data for the Roman population are consistent with previously identified widespread lead pollution. The pre-Roman populations contain lead isotopic compositions consistent with highly localized, minor sources of lead. Together, these data provide unequivocal confirmation that the Romans in Londinium were exposed to elevated lead levels. Elevated blood lead levels would have resulted, negatively affecting their health and possibly contributing to declining birth rates.     

Conservation of knife handles from the Elizabethan warship Makeshift

Knife handles from an Elizabethan Warship, probably the Makeshift (1592), have been conserved by a new technique, supercritical drying. Many of the knife handles are complex composites containing wood, cloth, leather, iron and copper alloys, and the technique has allowed these to be conserved as single units, where alternative techniques would have damaged or destroyed one or more of the component parts. A further advantage for using supercritical drying is that it is a minimum of four times faster than freeze-drying. A total of eleven knife handles have been conserved by the technique, with minimal loss of surface detail. The results compare favourably with those of waterlogged wood samples conserved by freeze-drying.     

‘Dark cognition’: W.B. Yeats,J.G. Herder and the imperfection of tradition

In this article I connect Revivalist politics in nineteenth-century Ireland to Enlightenment epistemology by exploring how the ideal of the Irish – or Celtic – folk tradition is embroiled in the problematic of theoretical modernity. I dispute Seamus Deane's ideological characterisation of the Irish tradition, emerging from his encounters with the work of Edmund Burke and Matthew Arnold, and propose an alternative characterisation using Johann Gottfried Herder's theories of the Volk and the origin of language. I show how, at a crucial point in European history, the folk tradition modelled a view of cognition and modernity, which stood apart from analytic rationalism and based itself upon a positive evaluation of the obscurity of sensation. Finally, I read this literary-aesthetic model of what Herder called ‘dark’ cognition into Yeats's early folkloric works of the 1890s, especially The Celtic Twilight; and I make the argument that this often-neglected text does not represent a degeneration of folkloric integrity into Celtic mysticism but a comedic trait of folk modernity.