Medieval

English, soda Medieval Latin, sodanum, headache remedy) Long recognized in compounds, sodium was first isolated by Davy in 1807 by electrolysis of caustic soda. 

The windows in some medieval cathedrals show greater thickness at the bottom than at the top, owing to the slow flow of the glass under the influence of gravity. 

Also of value is the study of the history of technology (24,25) that affords insights into the history of the development of civilization. The eadiest existing written records, treatises of crafts people and artists on the techniques and materials with which they worked, date back to medieval times (26—29). For prehistoric human activities, the record is in the objects which remain, and only through the study of these can knowledge in this regard be furthered. 

Natron and ash of seaweeds provided the sodium which served as the flux in all glasses till the Medieval period. Wood ashes then came into use, which changed the glass formulation to such a degree that potassium salts became the principal fluxing alkaUes. 

D. V. Thompson, The Materials and Techniques of Medieval Painting Alien Urwia, London, 1936 republished Dover Publishing, New York, 1956. 

Ancient Silver Smelters Polluted the Hemisphere", The Record, Sept. 23, 1994, p. A-23 and P. Brimblecombe, "Attitudes and Responses Towards Air Pollution in Medieval England," H/rPo// Contr. Assoc. (Oct. 1976). 

Thermal treatment is used to destroy, break down, or aid in the desorption of contaminants in gases, vapors, Hquids, sludges, and soHds. There are a variety of thermal processes that destroy contaminants, most of which are classified as incineration. Incineration HteraHy means to become ash (from Medieval Latin, incinerare in or into ashes). With respect to the incineration of hazardous wastes regulated in the United States, however, there is a strict legal definition of what constitutes an incinerator. The Resource Conservation and Recovery Act (RCRA) definition of incinerator at 40 CFR 260.10 is... 

With the fall of the Roman Empire, the ancient water supplies petered out. In early medieval times, people were content to conduct local water in wooden pipes to public cisterns. The first wooden pipelines for water were laid at Liibeck about 1293 and in 1365 at Nuremberg. In 1412 the Augsburg master builder Leopold Karg first used wrought-iron pipes in conjunction with wooden pipes to supply water. Because of their propensity to corrosion, they seem to have proved a failure and a few years later they were exchanged for wooden, lead, and cast-iron pipes. 

Nitric acid, or aqua fortis as it was called in medieval times, has been known and used by mankind for centuries. At first, it was produced by heating a mixture of sodium nitrate (Chile saltpeter) and sulfuric acid. The product obtained was sodium hydrogen sulfate, and the nitric acid vapors escaping during this process were condensed ... 

Societies concern with air quality has evolved from medieval times, when breathing smelting fumes was a major hazard, to where we are today (see Chapter 1). In modem society, a parallel effort has been under way to improve air quality in the outside or ambient air, which is the focus of this book, and in the industrial occupational setting in manufacturing and other traditional jobs. A combination of events is moving many countries to consider the quality of air in other locations where we live parts of our lives. Attention is now being refocused on "indoor" air quality. 

Zinc was not intentionally made in medieval Europe, though small amounts were obtained by accidental condensation in the production of lead, silver and brass it was imported from China by... 

White, L., Jr. (1962). Medieval Technology and Social Change. Oxford Clarendon. 

Nor was Europe the only civilization to make increased use of waterpower in this era. Although not blessed with the same abundance of stable, easy-to-tap streams, the Islamic world also increased its use of waterpower. Medieval travelers mention numerous... 

The wood water wheels used in the medieval period were, by modern standards, inefficient. Medieval undershot and horizontal wheels probably had an efficiency of about 15 percent to 25 percent, medieval overshot wheels about 50 percent to 60 percent. Commonly, their power output was only about 2—5 lip. But relative to the alternatives available at the time—human or animal power—they offered a very substantial gain in power. 

By the end of the medieval period, growing European reliance on wind and waterpower had created the world s first society with a substantial dependence on inanimate power sources. 

White, L. (1978). Medieval Religion and Technology. Berkeley University of California Press. 

Venice became the world s glassmaking center in medieval times. Small, flat panes were produced by cutting and rolling flat hot, blown glass. This technique was used for the buildings constrncted by early European settlers in America. 

Clusters of metal atoms can form colloidal suspensions. Colloidal clusters of copper, silver, and gold in glass are responsible for some of the vivid colors of stained glass in medieval cathedrals. Even aqueous suspensions of metal clusters are known (Fig. 8.45). 

Study, ancient Maya diet shows a A N of 4.5%o (humans-herbivores). The 8 N values for mixed-diet humans in Schoeninger et al. (1983) seem always somewhat too positive for their supposed food European agriculturalists are about 8-10%o. Also, Bocherens et al. (1991) and Lubell et al. (1994) give similar values (aroimd +9%o) for medieval French and Neolithic humans from Portugal, respectively. The 8 N values (+9.3 and 11.6%o) of two human (Neanderthal) samples (Fizet et al. 1995) are very similar to those of associated carnivores but are only slightly higher than those of Neolithic humans. 

Fricke, H.C., O Neil, J.R. and Lynnerup, N. 1995 Oxygen isotope composition of human tooth enamel from medieval Greenland linking climate and society. Geology 23 869-872. 

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