Artesian well: Artesian well, well from which water flows under natural pressure without pumping. It is dug or drilled wherever a gently dipping, permeable rock layer (such as sandstone)
It is known to be the worst air-pollution event in the history of the United Kingdom, and the most significant in terms of its effect on environmental research, government regulation, and public awareness of the relationship between air quality and health. Bell, Michelle L. and Davis, Devra Lee. 2  Reassessment of the Lethal London Fog of 1952: Novel Indicators of Acute and Chronic Consequences of Acute Exposure to Air Pollution ( Environmental Health Perspectives , June 2001).
A History of the World's Most Dangerous Element. Cornell University Press. When plutonium was first manufactured at Berkeley in the spring of 1941, there was so little of it that it was not visible to the naked eye. It took a year to accumulate enough so that one could actually see it.