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81.
A multidisciplinary programme of research on Islamic pottery has been focused on questions of the dating, provenance and technology of Islamic pottery. One particular question has been the development of stonepaste, a material made primarily of crushed quartz with added frit-glass and clay. The combination of the different approaches of this study has revealed early foundations for the technology in ninth-century AD Iraq, apparently originating in the clay ceramic rather than the ‘Egyptian faience’ tradition. Subsequent and final practice developed in tenth- and eleventh-century AD Egypt. This technology becomes the primary body for all fine Islamic ceramics. 相似文献
82.
An important line of research concerning historical fertility patterns in currently developed countries of Europe has concluded that, prior to the fertility transition, marital fertility was essentially constant over time, and deliberate fertility control was virtually unknown. It has been argued that variations over time in overall fertility were largely the consequence of variations in nuptiality. Other researchers have challenged these views and present evidence for the existence of a significant minority of fertility controllers in pretransition populations. In this article, we find support for this second view and argue that (1) there was significant, non-random variation in marital fertility over time, prior to the transition; (2) in many cases, this variation in marital fertility was large relative to contemporaneous variations in nuptiality; and (3) in a substantial minority of the cases, the variation over time in pretransition marital fertility was so large that it is suggestive of deliberate fertility control. Thus, our findings question the view of fertility transition as an innovation in deliberate marital fertility control. While most of our evidence is based on data from England and Wales, we find corroboration of our key results in other European data. 相似文献
83.
84.
The possibility of lead isotope fractionation in ancient lead production is examined. Kinetic theory relating to isotopic fractionation in non-equilibrium evaporation is considered and the feasibility of the alteration of lead isotope abundance ratios in ore roasting and smelting is assessed. Previous experimental work is shown to have been inconclusive and conclusions are drawn on the need for further research to quantify the possible extent of fractionation in practice. 相似文献
85.
86.
John Coates Seán McGrail David Brown Edwin Gifford Gerald Grainge Basil Greenhill Peter Marsden Boris Rankov Colin Tipping Edward Wright 《International Journal of Nautical Archaeology》1995,24(4):293-301
The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field. 相似文献
87.
88.
Pedro Pérez Herrero 《Colonial Latin American Review》1995,4(1):217-232
Tráfico de Indias y política oceánica. By Fernando Bordejé Y Morencos. Madrid: MAPFRE, 1992. Pp. 341.
Relaciones económicas entre España y América hasta la independencia. By John R. Fisher. Madrid: MAPFRE, 1992. Pp. 280.
Las comunicaciones en América. By Secundino‐José Gutiérrez Alvarez. Madrid: MAPFRE, 1993. Pp. 424.
Piratas, bucaneros, filibusteros y corsarios en América. Perros, mendigos y otros malditos del mar. By Manuel Lucena Salmoral. Madrid: MAPFRE, 1992. Pp. 306.
El dinero americano y la política del imperio. By María Emelina Martín Acosta. Madrid: MAPFRE, 1992. Pp. 333.
Cargadores a Indias. By Julian B. Ruiz Rivera and Manuela Cristina García Bernal. Madrid: Mapfre, 1992. Pp. 395. 相似文献
89.
90.
There is increasing concern about environmental impacts of acidic drainage from acid sulphate soils on Holocene estuarine flood plains. Acidity derives from oxidation of iron pyrite in the sediments. Natural factors determine concentrations and distributions of pyrite accumulations, but human activities have reduced pyrite accumulation in the Pearl River Delta with land use practices increasing terrestrial sediment discharge. Large freshwater discharges and management techniques have enabled sustainable use of these soils. High concentrations of pyrite occur in many estuarine flood plains of Australia because of relatively greater marine inputs. Drainage of these soils enhances pyrite oxidation and estuarine acidification, which is associated with fish-kills. For sustainable development, the problems of acid sulphate soil drainage must be recognised and overcome. 相似文献