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11.
A total of forty-nine stringed instruments of the Conservatory Cherubini collection, at the Musical Instruments Department of the Accademia Gallery in Florence, were submitted to a dendrochronological investigation in order to date them, check the validity of their attribution and to find out more about their construction characteristics. Thirty-seven instruments were successfully dated, thereby determining the terminus post quem date of manufacture. The correlation values of the statistical cross-dating tests were generally very high. The dendrochronological analyses determined which instruments had been made from wood of the same provenance and, in some cases, from the same tree trunk. The mean chronology built from the musical instrument series, named “Accademia Master Chronology”, is 558 years long and dates from 1396 to 1953AD. The interval between the youngest ring dated dendrochronologically and the given date of manufacture increased constantly in the course of the centuries, from a mean value of just over eleven years for instruments built in the eighteenth century, to nearly 74 years in the twentieth century, when the use of old wood from other artefacts became more frequent. Furthermore, in the Cherubini Collection, the average tree rings on violins are smaller than those of other stringed instruments; in fact, they increase in proportion to instrument size and are widest in cello and double bass.  相似文献   
12.
Despite its worldwide use as a stone tool raw material, quartz is known to be a difficult material for archaeologists. The main reason for this is the tendency of quartz flakes to fragment during detachment, which complicates the use of traditional lithic analyses. In this article we present an experimental study of quartz flake fragmentation. We evaluate the method called fracture analysis that has been developed and used explicitly for the study of quartz assemblages. The method assumes high predictability of quartz flake fragmentation, but our experiments show that there is significant variation in fragmentation that fracture analysis does not take into account. Our results indicate that this variation is partly explained by indenter hardness, the relative thickness of the detached flake, as well as individual knapper-related factors. These results undermine the applicability of quartz fracture analysis in its current form. In addition, we discuss the effects of flake fragmentation on the technological organisation of prehistoric quartz users and suggest that it has affected reduction strategies as well as blank and tool dimensions. We also suggest that there should be mobility-related differences in archaeological assemblages in terms of the quality of the quartz raw material and that the curation of quartz should be low in relation to better quality raw materials used parallel with it.  相似文献   
13.
The Analysis of Stone Tool Procurement, Production, and Maintenance   总被引:2,自引:0,他引:2  
Researchers who analyze stone tools and their production debris have made significant progress in understanding the relationship between stone tools and human organizational strategies. Stone tools are understood to be morphologically dynamic throughout their use-lives; the ever-changing morphology of stone tools is intimately associated with the needs of tool users. It also has become apparent to researchers that interpretations of lithic analysis are more productive when the unique contexts and situations for which lithic artifacts were made, used, modified, and ultimately discarded are considered. This article reviews the recent literature on stone tool production with an emphasis on raw material procurement, manufacturing techniques, and tool maintenance processes as they relate to adaptive strategies of toolmakers and users.  相似文献   
14.
The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.  相似文献   
15.
The lithic assemblage from the Middle Palaeolithic site of Payre (Rhone Valley, France) contains a large number of convergent tools and pointed tools of various shapes, sizes and retouch types. These were excavated from several archaeological units, dating from marine isotopic stages 8–5, which also yielded human skeletal remains. Consideration of this large tool kit has led to an improved analysis of Middle Palaeolithic tools with two retouched convergent edges. The 350 tools were not described within the classical typological framework, but, rather, from a lithic technological perspective in relation to a discoid debitage. In addition, an initial macroscopic use-wear analysis aided in establishing whether they were used according to their technical and/or morphological features. The Middle Palaeolithic convergent tools from Payre are shown to be quite diversified, and the question of the significance of the retouch and the definition of the various types is addressed. Initial functional results indicate that a clear relationship between shape and function cannot be easily established, and that these tools were used as hand tools. This study contributes to the debate on the use of stone tip spears in the Early European Middle Palaeolithic.  相似文献   
16.
This study discusses the existence of a variability recorded in lateralization indexes of proximal microburins, a by-product of the individual manufacture of microliths, in a sample of Sauveterrian sites from the Italian Eastern Alps. At first glance, such variability may appear to support the existence of customary handling, pertaining perhaps to an ensemble of normalized technical procedures accomplished by the members of the human group regardless of site type, context and economic activities. However, plotting the patterns in lateralization index against the regional Sauveterrian chrono-cultural sequence reveals a diverse correlation emerges and indicates how the early settlement phase involved greater functional differentiation among sites used by selected human groups compared with the successive phases, when this pattern vanishes. This trend may correspond to the decrease in lateralization observed on skeletal markers from the Upper Paleolithic to the Mesolithic, linked to the change in technological models and techniques employed in food gathering. The implications of this research at different levels are also discussed.  相似文献   
17.
The archaeological transition from Clovis to Folsom and Midland in the North American Great Plains coincides with the end of the Pleistocene and onset of the Younger Dryas. Comparisons exploring the adaptive changes that took place during this period frequently employ regional-scale approaches. The focus on regional-scale analyses largely results from the dearth of sites repeatedly visited by multiple early Paleoindian groups. However, regional-scale comparisons have the potential to overlook smaller-scale differences. The Debra L. Friedkin site, Texas offers an opportunity to study Midland, Folsom, and Clovis technology and site-use at a single site. This paper presents the context and chronology of the Midland, Folsom, and Clovis assemblages and a site-scale analysis of lithics from the Friedkin site. It is argued that point production and late-stage reduction were primary activities, and the use of bifacial cores for flake tools was important throughout these occupation periods. Site use at Friedkin differs from early Paleoindian occupation at the nearby Gault site and expands our understanding of settlement and technological organization in the region.  相似文献   
18.
Clovis points are the principal diagnostic artifacts of a Clovis complex that spread across North America between ca. 11,050–10,800 radiocarbon years before present. Clovis may be the best documented Paleoamerican culture in North America, but much remains to be learned about the movement and interactions of Clovis peoples. Similarities among Clovis points from geographically diverse locations have led some researchers to suggest that a uniform projectile point technology existed across North America during Clovis times. Others have rejected this idea, proposing local and independent technological adaptations to different regional environments. To investigate these ideas, we used digital morphometrics to analyze 50 Clovis points from nine different contexts. First, 3D surface models of the points were created with a portable laser scanner. Next, these models were digitally cross-sectioned through both faces, yielding two-dimensional isoheight contours of flake scar patterns that reflect the original reduction techniques used to shape the projectile points. In the final step, the contours were transformed with elliptic Fourier analysis into Fourier coefficient series, and patterns of variation and symmetry were explored with principal components analysis. When compared to modern Clovis point replicas made by an expert knapper, the flake scar contours of the ancient Clovis points showed little morphological variation and a large degree of bifacial symmetry. Our results support the existence of a widespread standardized “Clovis” knapping technique, most likely transmitted through direct interaction between knappers from different groups.  相似文献   
19.
Integrating portable X-ray fluorescence (pXRF) instrumentation into archaeological investigations has generated as much interest as skepticism because several characteristics of the technique limit analytical accuracy and precision. This paper seeks to explore inter-instrument performance in order to assess the potential pXRF instrumentation has in examining the elemental composition of lithic raw materials. Two pXRF instruments, Delta and Omega models both manufactured by Olympus Innov-X Systems, were utilized to obtain the trace element signatures of five fine-grained volcanic sources and four obsidian sources in the Great Basin. We compared the two portable instruments to a wavelength-dispersive instrument extensively calibrated with geologic standards and to a commercial benchtop energy-dispersive system. Our results suggest that the relationships between the data produced by these different instruments are complex, and as we look to the future of pXRF use in archaeological analysis we argue that that the same strict protocols applied in laboratory-based XRF analyses, involving instrument calibration, evaluation of inter-instrument performance, and comparison to accepted geologic standards, need to be applied in pXRF analysis.  相似文献   
20.
This article investigates how presidential policy attention is allocated across policy tools and whether there is a channeling of tool use by policy area. I also examine whether there is evidence of disproportionate information processing within presidential policy attention allocation and whether it is common across presidential policy tools. Presidential messages, hearings on administrations' legislative proposals, amicus briefs, and executive orders are employed to capture presidential policy tools. The allocation of attention via these four instruments is examined from 1957–2007 in the policy areas of defense and foreign affairs, macroeconomics, banking and commerce, civil rights, law and crime, and labor and immigration. I find that there is a canalization of presidential policy attention by instrument, and that the opportunity structure of policy tools shapes attention allocation. Additionally, I find evidence for punctuated equilibrium theory in the allocation of presidential policy attention via these four tools. When presidents do shift their attention to an issue area, they often attack the issue with some coordination of their policy instruments.  相似文献   
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