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The early modern period in England (c. 1500-1800) brought on a revival in local glass production. Medieval glass had been limited to the small-scale production of forest glass for window glass and vessels, predominantly in the Weald.〔Kenyon, G.H., 1967. ''The Glass Industry of the Weald'' Leicester, Leicester University Press〕 The organisation of production evolved from the small-scale family-run glass houses typical of forest glass-making to large monopolies granted by the Crown.〔Godfrey, E., 1975. ''The Development of English Glassmaking 1560-1640''. Oxford, Claredon Press.〕 The influx of immigrants from Europe brought changes in furnace technology and raw materials, creating a better quality glass.〔Crossley, D.W., 1990. ''Post-Medieval Archaeology in Britain'' New York, Leicester University Press〕〔Crossley, D.W., 1998. "The English Glassmaker and his search for materials in the 16th and 17th centuries." In McCray, P (ed) ''The Prehistory and History of Glassmaking Technology'', Westerville: Ohio, American Ceramic Society, 167-179〕 Monastic decrees later banned the use of wood fuel which was then replaced by the less expensive alternative of coal.〔〔〔Willmott, H., 2005. ''A History of English Glassmaking AD 40-1800'', Tempus Publishing Limited〕 The development of lead glass in the late 17th century propelled England to the forefront of the glass industry and paved the way for advancements in the Industrial Revolution.〔Charleston, R. J., 1984. ''English Glass and the Glass used in England ca. 400-1940''. London, Allen and Unwin〕 ==Chemical composition== Glass has three major components: a ''network former'' (silica), a ''network modifier'' (flux), and a ''network stabilizer'' (predominantly lime).〔Terence Maloney, F.J., 1967. ''Glass in the Modern World''. Science and Technology Series. London, Aldus books.〕〔Dungworth, D., 2003. ''Scientific Examination of Glass and Glassmaking Materials from Silkstone, Yorkshire''. Centre for Archaeology, English Heritage Report 90/2003〕 In the early 16th and 17th centuries glassmaking (the manufacture of glass from raw materials) and glassworking (the creation of objects from glass) occurred within the same glasshouse.〔Crossley, D.W., 1967. "Glassmaking in Bagot's Park, Staffordshire, in the Sixteenth Century." ''Post-Medieval Archaeology'' 1,67-72〕 Glass was also recycled at this time in the form of cullet.〔 In the early modern era, network formers were obtained from fine or coarse sands which were usually located near the area of production or from silica based pebbles.〔〔 Network modifiers were used to alter the chemical composition of the network former and reduce the melting temperature of the batch.〔〔〔〔 These fluxes varied depending on the type of glass. Potassium oxide (K2O) based alkalis were used extensively in glass production.〔 The type of flux selected heavily influenced the quality of the glass produced. In England, beech wood and oak were preferred for forest glass.〔 For soda-lime glass (Na2O), alkalis were often found in the form of marine plants – either local kelp or imported plants from the Mediterranean and the Near East (barilla, polverine, rochetta, sevonus, natron).〔〔 These were often used for the production of 'white' ''crystallo'' glass, a colourless glass or ''façon de venise'', colourless glass of the highest quality.〔〔〔Willmott, H., 2002. ''Early Post-Medieval vessel Glass in England c. 1500-1670'' Council for British Archaeology, Research Report 132〕 Network stabilizers in early modern England continued to be lime sources.〔〔 Lime occurs as a natural contaminant in most sands, and may also be intentionally added to the melt.〔〔Frank, S., 1982., ''Glass and Archaeology''. London: Academic Press〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Early modern glass in England」の詳細全文を読む スポンサード リンク
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