Precision in the X-ray fluorescence analysis of sixty-one Augustan quadrantes

Sixty-one Augustan quadrantes were analysed for calcium, iron, nickel, copper, silver, tin, antimony, and lead by X-ray fluorescence. Most coins contained about 99·7% copper with the other seven elements present as trace impurities. Significant differences in composition were found for the three different issues of quadrantes minted in c. 9 BC indicating that these issues were not minted exactly contemporaneously. Quadrantes minted in c. 4 BC have trace element concentrations in ranges that differ from those of the 9 BC quadrantes. The precision is very good for all trace elements (the precision of calcium was not calculated): average standard deviations are 0·0021% for Fe, 0·0026% for Ni, 0·0038% for Ag, 0·0014% for Sn, 0·0031% for Sb, and 0·015 for Pb.     

Iron-57 Mössbauer spectral studies of medieval stained glass

⁵⁷Fe Mössbauer spectral data for six excavated and two simulated medieval stained glass samples are reported. Iron-containing precipitates are observed in the two simulated medieval glasses and are responsible for the amber colour of these samples. The ferrous/ferric ratio of the other samples is dependent on the glass composition and glass making conditions. The green glasses are associated with the presence of both ferrous and ferric iron, the ratio being very similar in three of the glasses studied, while in the purple and emerald green glasses the iron which is constitutionally incorporated in the glass is solely in the ferric oxidation state. The UVvisible spectra of some of the glasses are used to assist in interpretation of the colourant action of iron, and the role of Mössbauer spectroscopy in linking separate glass fragments with a common source is also indicated.     

Hydraulic engineering and irrigation agriculture in the Moche Valley,Peru: c. A.D. 1250–1532

This paper examines the hydraulic properties (i.e. velocity and discharge) of the main late prehistoric canals of the Moche Valley. Velocities, estimated from excavated canal sections using the Manning flow equation, are compared to tables of maximum permissible velocities and reveal that canals were constructed to transport water efficiently, but that on gradients steeper than 1:100 the Chimu and Inca engineers were unable to transport large discharges without severe erosional problems. Discharge estimates are compared with modern field requirements, using a known ethnographic watering cycle. This demonstrates that in almost every instance the channel size was of the same order of magnitude as that predicted from the requirements. The construction of the Inter-valley canal to bring water to the state lands in Moche was a technological disaster.     

From excess to encompassment: Repetition,recantation, and the trashing of time in Swedish Christianities

ABSTRACT

I explore the conversion of a Swedish Pentecostal Prosperity preacher to the Roman Catholic Church in order to examine questions of analytical perspective, temporal scale, and ethical discernment in the operation of religiously charged forms of repetition. The paper juxtaposes neo-Pentecostal with Roman Catholic understandings of temporality through tracing the ideological movements of Pastor Ulf Ekman over the past three decades, summarizing these understandings as based around tropes of ‘excess’ and ‘encompassment’ respectively. In exploring repetition as both theoretical category and ethnographic object of observation, I distinguish between actively marked repetition and the merely repetitious, while also drawing distinctions between continuity and the iterative, oscillatory character of repetitive actions.     

Production technology and knowledge transfer of calcite-tempered grey ware bowls from 2nd- to 5th-century ce Noricum (Austria)

Aspects of 2nd- to 5th-century ce Roman production technology and knowledge transfer in southern Austria (known as Noricum) were examined. With no evidence for workshops identified in the study area, 44 grey ware bowls from two sites at Aguntum and Lavant were studied macroscopically, and combined with optical microscopy, X-ray powder diffraction, prompt gamma activation, neutron activation and scanning electron microscopy, in order to understand whether one (large) workshop supplied these bowls, or whether the bowls were produced by several (small) workshops nearby. Combined with information from the geological background, the results were used to tentatively indicate the production location. The results indicate that the grey ware bowls from Aguntum and Lavant were produced by local workshops nearby. The bowls were manufactured with similar clay sources, tempered with crushed calcite-marble rocks from the Tauern Window, their surface smoothed and burnished, and fired between 800 and 850°C in a reducing atmosphere of an open fire. This is taken to suggest that Roman potters, who were located at Aguntum and Lavant, shared strategies of raw materials selection, paste preparation, finishing and firing, and transferred technological knowledge through time.